College of Agriculture

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The College of Agriculture is committed to advancing agricultural education, research, and community service. It serves as a center for knowledge creation and dissemination in crop science, animal production, natural resource management, and sustainable agriculture.

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ASSESMENT OF FACTORS INFLUENCING ADOPTION OF AGROFORESTRY TECHNOLOGIES IN HALABA SPECIAL WOREDA, SOUTHEREN ETHIOPIA
(Hawassa University College of Agriculture, 2016) MIHRETU ERJABO
Halaba special district is characterized by drought, soil erosion, high population pressure, poor livestock production, lack of feed for livestock, very deep water table, very low productivity of crops and food insufficiency. In order to address these problems, the woreda Agricultural Development office along with other management practices such as soil physical conservation measures agroforestry was introduced decades ago as a means to alleviate the problem. However, the level of agroforestry adoption remains low. The main objective of this study was to identify the factors that influence adoption of agroforestry technologies by farmers in the district. Random sampling procedure was employed to select two kebele administrations and respondents. Data collection was conducted by employing five different types of techniques such as rural household questionnaire survey, participatory rural appraisal, questionnaires for local and woreda extension staff, scanning government records & secondary data resources and field observation. A total of 12 key informants, 6 extension staffs and 182 households, samples were used in the data collection process. Chi-square test and t-test were used to determine whether there were statistically significant relationships between adoption of agroforestry and 15 selected variables. Out of which eleven were found to be significant to affect farmers’ adoptiveness. These were frequency of visits of farmers(13.39%), participation in training(11.49 %), farmers’ attitude towards agroforestry practices(10.61%), frequency of visits of extensionists(10.38%), participation in extension meeting(10.34%), participation in field day(10.28%), land holding size(9.29%), level of literacy(8.78%), awareness about the importance of agroforestry technology packages(7.06%), time taken from their residence to nearest extension(5.04%) and gender of respondents(3.34%). This study also identified various factors that may result in low adoption rates of agroforestry including fear of competition between trees & crops for water and nutrients uptake, seedling shortage, rainfall shortage, free grazing after crop harvest, financial problem, labor shortage, expecting trees as soil degrader & long span of trees and lack of need ranking of farmers by extension staff. To improve farmers’ adoption, the factors identified should be well addressed by launching a series and recurrent outreach extension program appropriate and suitable to farmers need.
EFFECT OF INTRA-ROW SPACING ON GROWTH PERFORMANCE AND YIELD OF ONION (Allium cepa L.) VARIETIES AT MIZAN-AMAN, SOUTHWESTERN ETHIOPIA
(Hawassa University College of Agriculture, 2016) DIRO BUZAYO TOLESSA
Onion is among the most important vegetable crops produced in Mizan-Aman for home consumption and as income sources. However, lack of site based varieties and inappropriate planting density have been the major bottlenecks of onion production and productivity in the area, since there are no recommended spacing and variety for that area specifically. Rather farmers use to practice non-uniform plant spacing. This study was thus conducted at Mizan ATVET College in 2015/2016 with the objective of investigating the effect of intra-row spacing on growth performance and yield components of onion varieties. Three varieties (Adama Red, Bombay Red and Melkam) were evaluated under four different intra-row spacings (6, 10, 14 and 18 cm) and constant inter-row spacing of 20 cm by using randomized complete block design replicated three times. Data on days to maturity, growth performance and yield were recorded and subjected to analysis of variance using SAS version-9 software. Results of the study indicated that, intra-row spacing and variety had significant effect on plant height, leaf number per plant, leaf length, days to maturity, bulb diameter and length, bulb dry matter, total bulb yield as well as, marketable and unmarketable bulb yield. Closer intra-row spacings enhanced early maturity, while wider spacing delayed maturity. The maximum plant height, leaf length and leaf number were recorded in 10 cm intra-row spacing. Bombay Red variety was early maturing with the highest mean value for growth and yield parameters. It had the highest total bulb and marketable bulb yield than Melkam and Adama Red onion varieties specially when planted at 10 cm intra-row spacing. Bombay Red with 10 cm intra-row spacing also gave highest total bulb and marketable bulb yield. The correlation values also confirmed the significant and positive association between growth parameters and bulb yield. Based on the result of this study, higher onion yield with better quality was attained when Bombay Red variety was planted with 10 cm intra-row spacing under Mizan-Aman condition, for recommendation, although additional verification trial is needed to substantiate the result.
GROWTH, SYMBIOTIC AND YIELD PERFORMANCE OF SOYBEAN (Glycine max L.) VARIETIES IN RESPONSE TO Bradyrhizobium INOCULATION AND PHOSPHORUS APPLICATION AT ASSOSA, WESTERN ETHIOPIA
(Hawassa University College of Agriculture, 2017) TESFAYE TEKOLA SEIFU
This research was conducted during 2016 main cropping season on field at Assosa, in Benishangul Gumuz Regional State with the objectives of investigating growth, symbiotic and yield performance of three soybean (Glycine max L.) varieties in response to Bradyrhizobium inoculation and P fertilizer application. The treatments studied included three P levels (0, 10 and 20 kg P ha -1 ), two inoculation levels (uninoculated and inoculated with Bradrhizobium strain; MAR-1495) and three soybean varieties (Gizo,Belessa-95 and Local) in randomized complete block design with factorial arrangement using three replications. The results revealed that Bradyrhizobium inoculation with MAR-1495 significantly (P<0.01) increased most of the parameters studied as compared to the control. Inoculation with strain MAR-1495 significantly (P < 0.01) increased nodule number, nodule dry weight, shoot dry weight, root dry weight, leaf area, grain yield, and above ground total biomass as compared to the control. Application of P at 20 and10 kg ha -1 significantly increased nodule number, nodule dry weight, and root dry weight, shoot dry weight, leaf area, above ground total biomass and grain yield. There was significantly (P < 0.01) cultivars effect for most of studied parameters; Belessa-95 variety had better responded on nodule number, nodule dry weigh, grain yield and above ground total biomass as compared to Gizo and Local varieties. The highest grain yield was recorded from Belessa-95 variety 3.29 ton ha -1 from combined application of 20 kg P and Bradyrhizobium inoculation. Nodule number plant -1 was positively and significantly correlated with most of growth parameters, yield and yield components. It could, thus, be deduced that use of MAR-1495 Bradyrhizobium strain and Belessa-95 variety with application of 20 kg P markedly increased the productivity of the crop at Assosa area, however economic analysis revealed that the highest net return was obtained from application of 10 kg P and Bradyrhizobium inoculation with strain MAR-1495. The use of MAR-1495 strain and Belessa-95 variety with application P at 10 kg ha -1 could be recommended, but verification of the results on different farmers’ field could be required before wide use of this study.
EFFECTS OF SEEDLING AGE AND VARYING RATES OF PHOSPHORUS ON GROWTH AND YIELD PERFORMANCE OF ONION (Allium cepa L.) UNDER IRRIGATION IN ALAGE DISTRICT, CENTRAL RIFT VALLEY OF ETHIOPIA
(Hawassa University College of Agriculture, 2017) TILAYE ANBES WASIE
Onion is an important cultivated crop used as a condiment as well as a source of income for many farmers in Ethiopia. However, the yield of the crop is constrained by a number of factors among which inappropriate transplanting age and poor fertilizer management practices are important factors. Therefore, a field experiment was conducted at Alage Agricultural Technical and Vocational Education and Training College (Alage) campus, Central Rift Valley of Ethiopia, during 2016/17 season to determine the effect of seedling age and phosphorus rate on growth and yield performance of onion. The treatments comprised of three seedling ages (6, 7 and 8 weeks of seedling age) and four phosphorus rates (0, 46, 92 and 138 kg ha -1 ). The experiment was laid out in randomized complete block design (RCBD) with four replications. The result showed that seedling age and phosphorus rate significantly affected plant height, leaf length, days to maturity, fresh bulb weight, bulb dry matter fraction, bulb length, marketable bulb yield, total bulb yield, harvest index, medium and large sized bulb yield. Among these parameters, marketable bulb yield, total bulb yield and harvest index were also significantly affected by the interaction of seedling age and phosphorus rate. On the other hand, leaf number per plant, bulb diameter, bulb dry weight, total biomass yield, small bulb sized yield, under sized bulb yield and unmarketable bulb yield were only influenced by the main effect of phosphorus rate. In this study result, transplanting at 8 weeks of seedling age fertilized with 138 kg P 2O5 ha -1 recorded the highest total bulb yield (50.6 t ha -1 ) and marketable bulb yield (48.33 t ha -1 ), but no significant difference was showed with that obtained at 92 kg P 2O5 ha -1 with the same seedling age. Treatment combinations of seedling age at 6 weeks and no P (control) produced the lowest amounts of total bulb yield (24.27 t ha -1 ) and marketable bulb yield (21.63 t ha -1 ). The partial budget analysis revealed that the highest net benefit with low cost of production was obtained in response to the application of 92 kg P2O5 ha -1 and the transplanting age of 8 weeks. The marginal rate of return for this treatment was 5657% which is found to be economically feasible for producing onion in the study area.
THE DYNAMICS OF LAND USE MANAGEMENT ON CARBON SEQUESTRATION, SOIL PROPERTIES AND VEGETATION ATTRIBUTES IN BORANA, SOUTHERN ETHIOPIA
(Hawassa University College of Agriculture, 2018) KENEA FEYISA JIRATA
The Borana rangelands of southern Ethiopia have been extensively used as grazing lands by pastoralists for millennia.However, there has been a dramatic shift from prime grazingland to cultivation, left unused because of bush encroachment, and highly degraded leading to different land use/land cover types in the region. Therefore, this thesis work was designed to study the dynamics of land use management on carbon sequestration, soil properties and vegetation attributes by considering the roles played by enclosure management, different land use systems, the aboveground biomass of woody species, and long-term ban of prescribed range fire. This study was conducted in Yabello district of Borana, southern Ethiopia during the period from June-August 2013. A paired-site design approach was used in this study, where sampling plots (30 m x 30m each) with nested’ subplots for field data collection on soil and vegetation layers were establishedin a systematic random sampling techniquealomga 500 m long transect line in each adjacent experimental site.Using enclosures versus the adjacent open-grazed as control, our results showed that the SOC and TN contents and stocks increased in enclosures as compared to the adjacent open-grazed rangelands, although the differences were not significant (P > 0.05) and varied along the age sequence and soil depths.Overall, totalmean SOC stocks of 39.6 ± 3.5 Mg ha−1 in the younger (< 20 years old), 40.8 ± 3.4 Mg ha −1 in the medium (20–30 years old ) and and 51.0 ± 4.4 Mg ha −1 in older (> 30 years old) enclosures age categories, whereas in the adjacent open-grazed areas the values ranged from 34.4 ± 2.5 to 47.9 ± 5.1 Mg ha−1in 0-30 cm. The herbaceous biomass was significantly (P<0.05) higher inside enclosures (115.4 gm m-2) than that of the adjacent open-grazed rangeland areas (43.6 gm m -2).The study in this thesis showed that the Borana rangelands had undergone substantial changes in land use/land cover during the last 37 years. Our results also showed that mean SOC stocks (0-30 cm) in woodland was 55.94±3.41 Mg ha-1,while for enclosure, grazing xvii and cultivated lands the values were 50.03±3.03, 45.79±4.00 and 38.10±2.39 Mg ha -1 , respectively. Additionally, woodland had the highest (7.52±0.43 Mg ha-1), while cultivated land had the lowest (5.58±0.35 Mg ha-1) total nitrogen stock. The potential changes of SOC and TN stocks also showed both gain and loss based on the present measurements and historical land use change. The developed species specific and mixed species allometric equation models for majorities of the investigated woody species ithat related the total above-ground, stem and branches biomass components well fit to the measured dendrometric variablesas as indicated by their adjusted coefficient of determinations and highly significant (adj.R² > 0.80; P < 0.001). The study on long-term of ban of fire on carbon stocks in soil and woody biomass, and TN stock across the two landscape site showe that relatively higher SOC and TN contents and stocks as well as herbaceous biomass carbon in burned than unburned areas, whereas more accumulation of woody biomass carbon was recorded in the unburned sites (40 years of fire exclusion).Overall, this study will contribute to the existing knowledge gaps in terms of the potential of SOC and TN stocks related to different rangeland management practices as well as anestimate of the above-ground woody biomass in arid and semi-arid ecosystems of southern Ethiopia. However, it is suggested further study including other variables such as climatic factors, seasonality and inherent soil properties across wider landscapes, which may have confounding effects on the dynamics of carbon sequestration other than land management practices for the sustainable use of the savanna rangelands of southern Ethiopia.
EFFECT OF NITROGEN SOURCES ON GROWTH, YIELD AND YIELD COMPONENTS OF COMMON BEAN (Phaseolus vulgaris L.) VARIETIES AT MESKAN, SOUTHERN ETHIOPIA
(Hawassa University College of Agriculture, 2019) MESERET SHIFA
Common beans (Phaseolus vulgaris L.) are an important cash crop and protein source for farmers in many parts of Ethiopia. However, lacks of adequate information on the use of nitrogen source fertilizers are the major yield limiting factors for common bean production in the study area. Thus, the field experiment was conducted at Meskan District in 2018 cropping season to evaluate the effect of nitrogen sources on growth, yield and yield components of common bean varieties; and to identify economically appropriate combination of nitrogen sources that give optimum yield of major common bean varieties. Factors studied includes four common bean varieties (Hawassa Dume, Gegeba, Rori and Ibado) and four level of N sources (T1= Control; T2=Rhizobium inoculated; T3=46 kg N ha -1 , T4= 46 kg N ha -1 + Rhizobium inoculated). The treatments were arranged using randomized complete block design in factorial arrangements with three replications. Results revealed varietal differences on growth, yield and yield components. The highest pod number plant -1 (29.1), seed number pod -1 (5.6) and grain yield (2.7 t ha -1 ) were recorded from variety Hawassa Dume. Similarly, nitrogen sources had significant effect on growth, yield and yield components. Significantly, higher number of pods plant -1 (27.5), seeds pod -1 (5.6), and grain yield (2.7 t ha -1 ) were recorded from combined application of Rhizobium inoculation+46kg N ha -1 . There was significant interaction effect of N sources with varieties on nodule number, root dry weight and straw yield, where by the highest nodule number plant -1 (40), root dry weight (11.6 ) and straw yield (4.5 t ha -1 ) were recorded from combined application of Rhizobium strain HB-429 and 46 kg N ha -1 with variety Hawassa Dume except number of nodule plant -1 . Grain yield was positively and significantly correlated with phenological, growth, nodulation, yield and yield components except maturity date. Partial budget analysis of the study revealed that the highest net return (32,748 ETB ha -1 ) was obtained from Hawassa Dume variety with combined application of inoculation and 46 kg N ha -1 . Based on the results of this study, it can be concluded that combined application of Rhizobium inoculation with 46 kg N ha -1 found to be appropriate for common bean variety Hawassa Dume in the study area. However, the result of the present study need to be evaluated and reconfirmed on farmers field across season and areas in order to reach to a conclusive recommendation.
GROWTH AND YIELD OF ONION (Allium cepa L.) AS AFFECTED BY VARIABLE RATES OF POULTRY MANURE AND MINERAL NITROGEN FERTILIZER AT ALAGE, CENTRAL RIFT VALLEY OF ETHIOPIA
(Hawassa University College of Agriculture, 2019) NEJEHA REDY ALEMAR
Onion is one of the important vegetable crops produced in many home gardens and in some extent commercially in different parts of Ethiopia. However, the average yield of the crop is low compared with the world average yield. Declining soil fertility and lack of information on appropriate fertilizer type and rates are the most important factors attributing for the low yield of onion in Ethiopia. Therefore, the field experiment was carried out at Alage Central Rift Valley of Ethiopia, during 2018/19 cropping season, with the objectives of assessing the growth, yield and quality response of onion to the variable rates of poultry manure and mineral nitrogen fertilizer. The experiment comprising of three nitrogen levels (0, 46 and 92 kg ha -1 ) and four levels of poultry manure (0, 5, 10 and 15 t ha -1 ) were laid out in randomize complete block design with three replications. Data on plant growth, yield and quality components were collected and subjected to ANOVA using SAS (9.2 version) software. The main effects of poultry manure and nitrogen fertilizer significantly affected the leaf length, leaf number, days to maturity, bulb length, unmarketable bulb yield and bulb dry matter content, except total bulb yield and marketable bulb yield. Plant height, bulb diameter and harvest index were significantly affected by the interaction of poultry manure and nitrogen fertilizer levels. Application of poultry manure at the rate of 15 t ha -1 recorded the highest total bulb yield (63.33 t ha -1 ) and marketable bulb yield (62.52 t ha -1 ), but statistically there were no x significant difference between 15t ha -1 and 10t ha -1 poultry manure application. Lower amount of total bulb yield (53.44 t ha -1 ) and marketable bulb yield (52.40 t ha -1 ) were obtained from the control plot as compared to the maximum yields obtained from other treatments. Marketable bulb yield was positively and significantly correlated with most of the growth parameters. The results of partial budget analysis showed that 15 t ha -1 poultry manure application gave the highest marginal rate of returns. Since, the highest bulb yield and maximum marginal rate of returns are obtained at 15 t ha -1 poultry manure application, this rate can be recommended for onion production in the researched area, and areas having similar agro-ecologies. However, as the research is conducted for a single season and location, repeating the experiment over location and year will be required to give a conclusive recommendation.
ECOLOGY AND INSECTICIDE RESISTANCE MANAGEMENT OF THRIPS (THYSANOPTERA: THRIPIDAE) ON ONION (Allium cepa L.) IN THE RIFT VALLEY OF ETHIOPIA
(Hawassa University College of Agriculture, 2020) BELETE NEGASH
Ecology and Insecticide Resistance Management of Thrips (Thysanoptera: Thripidae) on Onion (Allium cepa L.) in the Rift Valley of Ethiopia Belete Negash1 , Ferdu Azerefegne1 and Gashawbeza Ayalew2 1Hawassa University, College of Agriculture, Hawassa, Ethiopia 2 Ethiopian Institute of Agricultural Research, Melkassa Research Center, Adama, Ethiopia ABSTRACT Decline in efficacy of registered insecticides to control thrips (Thysanoptera: Thripidae) on onion in Ethiopia stimulated studies on insecticide resistance, ecology and management of thrips on onion in the major onion production belt of the Central Rift Valley of Ethiopia (CRV). Several studies including farmers‟ insecticide use practices against thrips on onion, species composition and abundance, seasonal abundance of thrips and their effect on yield, insecticides resistance detection and management were conducted from 2015 to 2017. Diazinon, dimethoate, profenofos, lambda-cyhalothrin and spinetoram were widely used for thrips control on onion in the surveyed areas. Type and frequency application of insecticides use were different among the locations. Insecticide application frequencies were higher at Meki and Melkassa than in Werer areas. All the onion fields visited during the survey were infested by two thrips species namely, the western flower thrips, Frankliniella occidentalis (Pergande) and the onion thrips, Thrips tabaci (Lindeman). Thrips species compositions vary with locations. While, T. tabaci was dominant in Werer and Melkassa areas. The F. occidentalis thrips species was dominant at Meki location. Thrips population was higher during mid-growth stage of onion, 50 to 64 days after transplanting, than early and late growth stages in cool dry (October–January), hot dry (February – may) and rainy (June – September) growing seasons. Significantly lower thrips population recorded in the rainy season than the cool dry and hot dry seasons. Onion growth stage, growing seasons and sunshine hours were important factors for predicting thrips numbers. Cool and rainfall seasons significantly negative correlated with thrips numbers, while it was positively correlated with the onion growth stage, maximum temperature and sunshine hours. Thrips number was significantly greater on untreated plots than insecticide treated plots except in the rainy season. Higher percent yield losses were recorded on planting made in cool dry and hot dry 2 seasons in both years than rainy season with 8.24 to 40.17% yield losses. Commonly used insecticides on thrips were evaluated for their efficacy both in field and laboratory condition. Plots treated with spinosad, spinetoram, and imidacloprid resulted in better control, which was comparable higher marketable yield of onion both in cool and hot dry seasons. While, alphacypermethrin, diazinon, neem and λ-cyhalothrin insecticides treated plots poorly performed in both seasons and had lower marketable yield. Performances of dimethoate and profenofos were intermediate with the intermediate yield gains over the control under field condition. Laboratory bioassay confirmed that the poor efficacy of λ –cyhalothrin and diazinon under field conditions was due to thrips resistance to these insecticides. Higher level of resistance was recorded to λ – cyhalothrin and diazinon in Meki and Melkassa collected thrips populations, whereas no resistances to profenofos, dimethoate and spinetoram insecticides in all tested thrips populations were found. From insecticides resistance management studies, the sequential application of the more effective insecticides, imidacloprid and spinetoram, followed by less effective insecticide λ-cyhalothrin resulted in better control with higher economic return. Adding a penetrating surfactant improved the efficacy of insecticides compared to those without a penetrating surfactant in both seasons. Onion growers will continue to rely on insecticides as part of thrips management. Hence screening of new molecules periodically to identify effective insecticides and deploying a resistance management strategy through, among others, rotational application should form integral component in the integrated management of thrips (IPM) on onion. Studies on non-chemical control methods including cultural such as intercropping with other vegetables, host plant resistance should be conducted with the aim of strengthen thrips IPM
ECOLOGY OF THE AFRICAN MAIZE STALK BORER, Busseola fusca(Fuller) (LEPIDOPTERA: NOCTUIDAE) ON MAIZE (Zea maysL.) IN SOUTHERN ETHIOPIA
(Hawassa University College of Agriculture, 2020) ABRHAM TADDELE TEREFE
Maize (Zea mays L.) is an important crop in sub-Saharan Africa (SSA) and the developing world. In Ethiopia, smallholderfarmers almost in allregions of the country dominantly produce maize. In sub- Saharan Africa, maize suffers from various biotic and abiotic constraints resulting in considerable yield loss. Among the biotic factors, insect pests particularly fall armyworm and stem borers are currently the most important pests of maize. Stem borers attack maize from seeding up to maturity. The sampling number and unit are important features of any empirical study in which the goal is to make inferences about a population. The number of sampling number and unit could vary with insects being sampled, their distribution patterns purpose of sampling, infestation pattern and economic considerations. Diapausing B. fusca larvae live in maize stem during unfavorable conditions. Environmental factors such as temperature influence the duration of B. fuscalarvae development, intensity and time of pest out break varied between localities. Information on pest incidence, injury and yield loss in the different agro-ecologies will facilitate strategic decisions with regard to selection of management practices. This study provides information on B. fusca, spatial distribution pattern, sampling size, phenology, population density and termination of diapauses larvae, crop injury, and yields losses in maize in southern Ethiopia. xxii During the study periods, B. fusca was present and injurious to maize in all study areas. The spatial distribution pattern of B. fuscawas determined by using four distribution indices namely, Taylor’s power law, Iwao’s mean crowding regression, Lloyd's mean crowding, and index of dispersion. At the mid-whorl stage of maize, the distribution of B. fusca infestation was aggregated and uniform at both silking and maturity stages. At silking as well as mid-whorl stage of maize, B. fuscalarvae exhibited an aggregated distribution pattern but, larvae at maturity stage and pupae in both silking and maturity stages of maize found randomly distributed. To set control options for B. fusca at its economic threshold level in maize farm, required sampling units was determined using four precision levels and Iwao’s patchiness regression. The required sample units to estimate 5 to 30% mean infestation of maize by B. fuscaranged from, 101 - 73, 45 - 32, 25-18 and 16 to 12 in 2015 and 104-76, 42-30, 26-19 and 17 to 12 in 2016, for 10%, 15% , 20% and 25% precision, respectively. For 10% infestation, which is considered as action threshold level for stem borers management on maize, 22 sampling units (660 plants) per hectare at the precision of 20% are required. The phenology of B. fusca was studied at Hawassa and Wolaita Sodo using sowing date and pheromone traps.Three generations of B. fusca per year were observed in southern Ethiopia between May and September. In Hawassa, the first moth flight which emerged from diapause larvae was started at mid-April in 2015 and mid of March, 2016. In Wolaita moth flight started at early May and April in 2015 and 2016, respectively. The potential of crop residues as sources of carry-over populations of the insect was also assessed. Flight period and population density of adult B. fuscafrom diapause state were significantly varied between seasons. Access to water did not enhance pupation during the diapause. Planting of maize at the beginning of April and May xxiii in Hawassa and Wolaita Sodo, respectively could be no longer suitable for oviposition and consumption by second-generation B. larvae. Population density of B. fuscalarvae and pupae were significantly different among years, locations and crop stages. Early and highest infestation of B. fuscaon maize was observed in Gurage followed by Wolaita as compared in Sidama Zone. Higher population density, injury variables and grain yield losses due to B. fuscaon maize were recorded from chemical treated plots as compared with untreated. Tunnel length, hole number, bored internode, larvae and pupae population had a negative effect on grain yield of maize. Increase in altitude positively affected the population density of B. fuscaand the resultant infestation and yield loss. Cultural practice such as crop diversification; disposal of crop residues after maturity can reduce initial establishment of stem borer infestation. Chemical control is one of the components of integrated pest management and should be used only when necessary combined with other management practices. This study provides information on the distribution, biology, pest status and yields losses due to B.fuscaon maize in southern Ethiopia.
RESPONSE OF MALT BARLEY (Hordeum vulgare L.) TO DIFFERENT RATES OF NPSB AND UREA FERTILIZERS IN BULE HORA WOREDA, GUJI ZONE, OROMIA REGIONAL STATE
(Hawassa University College of Agriculture, 2020) ASHENAFI TADESSE FOLLA
Malt Barley (Hordeum vulgare L.) is one of major crops grown in Bule Hora woreda,oromia region South western Ethiopia. The soil in the area is poor in most of the available nutrients due to intensive soil erosion and long history of cultivation. Therefore, a field experiment was carried out in 2019 cropping season to evaluate response of malt barley to the different rates of NPSB and N fertilizer. The treatments consisted of four levels of NPSB (0, 50, 100, and 150 kg NPSB ha -1 ) and four levels of N (0, 23, 46, 69 kg N ha -1 ). The experiment was laid out in three replication of the randomized complete block design in a factorial arrangement. The results revealed that the interaction effect had a highly significant (p<0.001) on Days to heading, Days to physiological maturity, thousand kernel weight, grain yield and Hectoliter weight. The main effect N fertilizer had a significant effect on spike length, number of tiller per plant, number of spikelet per spike and protein content. Blended NPSB also had significant (p<0.05) effect on number of effective tiller, above ground biomass. Plant height had significantly (p<0.05) by blended NPSB and N fertilizer The highest yield (3691kgha -1 ) was recorded from the interaction effect of 150 kg NPSB ha -1 and 69kg N ha -1 . The partial budget analysis also indicated that the best treatments were interaction of 150 kg NPSB ha -1 and 69kg N ha -1 , which gave net benefits of 63203 ETB ha -1 with acceptable marginal rate of return (5776%). Therefore, it could be concluded that application of 150 kg blended NPSB ha -1 with 69kg N ha -1 fertilizer rates were economically profitable yield and the application of 23kg N ha -1 acceptable for grain quality for malt barley production in the study area.
EFFECTS OF IRRIGATION FREQUENCY ON YIELD RESPONSE OF TWO COMMONLY GROWN TOMATO VARIETIES AT SHASHOGO WOREDA OF SOUTHERN ETHIOPIA
(Hawassa University College of Agriculture, 2020) GETAHUN LENDABO HELAMO
Tomato is one of the most important vegetable crops widely grown in Ethiopia. It has many nutritional values and considered as high value cash crop in the country. However, its productivity among small scale growers is far below its potential. This is partly due to lack of access and awareness to improved cultivars and agronomic packages. The objective of the study was to identify the response of two tomato cultivars under different irrigation intervals and to determine the optimum irrigation interval. The design was randomized complete block with factorial arrangement of two varieties (variety Galilea and variety Roma VF) and three irrigation intervals (4, 6, and 8 days), with three replications. The experiment was conducted from December 2018 to April 2019, at Shashogo Woreda of Southern Ethiopia. A Data were recorded on Phenological, growth and yield characteristics. Varieties differed significantly (P<0.05) in all characteristics, except in number of primary branches and fruit set percentage. Variety Roma VF was earlier by 8 and 13 days in days to first harvest and days to 50% maturity respectively than variety Galilea. Whereas variety Galilea had significantly (P<0.05) higher number of secondary branches per plant, clusters per plant, flowers per cluster, fruits per cluster, fruits per plant, marketable fruit yield and total fruit yield than Roma VF. Similarly, irrigation interval of 6 days resulted in higher values in all these characters than irrigation interval of 4 and 8 days. The highest net benefit of ETB 682,584 was obtained from Variety Galilea under irrigation interval of 6 days. Hence, economically attractive combination is to grow variety Galilea under irrigation interval of 6 days. Growing Roma VF under irrigation interval of 6 days might be considered when earliness is needed to meet special market demands.
EFFECT OF ALTERNATE FURROW IRRIGATION UNDER DIFFERENT MOISTURE REGIMES ON WATER USE EFFICIENCY, GROWTH, YIELD AND YIELD COMPONENTS OF COMMON BEAN (Phaseolus vulgaris L.) AT ALAGE, CENTRAL RIFT VALLEY OF ETHIOPIA
(Hawassa University College of Agriculture, 2020) HUNDE HAYILE TOLOSA
The farmers use common traditional irrigation methods which at times lead them to over irrigate, resulting in high water losses and low irrigation efficiency. Under such conditions understanding and application use of deficit and alternate furrow irrigation systems on crop production would enhance food security through improved water use. Thus, this study evaluated that the effect of alternate furrow irrigation under different moisture regimes on water use efficiency, growth, yield and yield components of common bean, during 2019 at Alage ATVET College. The experiment was laid out in factorial combination of two factors, following randomized complete block design in split plot arrangement with three blocks consisting twelve treatments; four irrigation levels (100% ETc (I 0 ), 80% ETc (I 1 ) 60% ETc (I 2 ) and 40% ETc (I 3) as the main plot and three irrigation methods (fixed alternate furrow irrigation (FAFI), variable alternate furrow irrigation (VAFI) and conventional furrow irrigation (CFI)) as the sub plot. This experiment showed that deficit irrigation (DI) and AFI significantly (P<0.01) affected days to physiological maturity, No of nodules plant -1 , grain yield, CWUE and IWUE. DI also significantly (P<0.05) influenced days to 50% flowering, stand count, plant height, No of branch, shoot dry weight, nodule dry weight, No of pods plant -1 , No of seeds pod -1 , pod length, 100-seed weight and HI. The interaction effect of DI and AFI also significantly (P<0.05) influenced the biological yield. Maximum (5.16 t ha -1 ) and minimum (3.38 t ha -1 ) biological yield was recorded at I0 and I 3 respectively with combination of FAFI and CFI, in that order. The highest grain yield was obtained under I 0 (2.45 t ha -1 ) and the lowest (1.34 t ha -1 ) was at I 3 . On the AFI, the maximum grain yield (2.11 t ha -1 ) was obtained under FAFI and the minimum (1.78 t ha -1 ) was under CFI. The uppermost CWUE (1.03 kg m -3 ) was recorded at I 3 followed by I 2 (0.92 kg m -3 ) and the smallest was at I0 (0.70 kg m -3 ) followed by I1 (0.77 kg m -3 ). The maximum CWUE (0.92 kg m -3 ) was recorded under FAFI followed by VAFI (0.86 kg m -3 ) and CFI (0.79 kg m -3 ). The partial budget analysis showed that I 0 , I 1 and I 2 gave marginal rate of return above the acceptable threshold value with additional investment advantages for the later. However, there was significant yield difference between I 0 and I 1 ; farmers can save 20% of the irrigation water in the expenditure of the reduced yield (0.33 ton ha -1 ). The highest net benefit was obtained from FAFI, thus the farmers option allows for FAFI at which high yield was recorded. Generally this analysis indicates that farmers at study area and related agro-ecology can use I 0 (100% ETc) in order to maximize their income from increased investment, but if there is lack of adequate irrigation water they can use I 1 (80% ETc) in order to save and use irrigation water more economically.
PERFORMANCE EVALUATION OF MUNG BEAN (Vigna radiata(L.) Wilczek) VARIETIES UNDER VARIABLE PHOSPHOROUS FERTILIZER RATES AT ALAGE, CENTRAL RIFT VALLEY OF ETHIOPIA
(Hawassa University College of Agriculture, 2020) HABTAM TILAHUN ASRATIE
Mung bean is an important pulse crop in Ethiopia. However, lack of adapted high yielding varieties and poor soil fertility, especially low levels of nitrogen and phosphorus, have been demonstrated to be important constraints for the production of the crop. Field experiment was conducted during the 2019 belg season to determine the Performance Evaluation of Mung Bean (Vigna Radiata(L.) Wilczek) Varieties Under Variable Phosphorous Fertilizer Rates at Alage Agricultural Technical and Vocational Education Training college Experimental field. The treatments consisted of factorial combinations of four mung bean varieties ( Boreda-1, N26, NVL-1 and shoa robit local) and four phosphorus fertilizer rates (0, 23, 46 and 69 kg P2O5 ha-1 ) laid out in Randomized Complete Block Design with four replications. Data were collected on plant height , number of nodules plant-1 , nodules dry weight plant-1 , root dry weight plant-1 , shoot dry weight plant-1 , number of branches plant-1 ,number of pods plant-1 , number of seeds pod-1 , hundred seeds weight, grain yield, harvest index, biological yield, days to flowering and maturity. The variety Boreda-1 showed the best performance in number of pods plant-1 , number of seeds pod-1 ,and grain yield whereas NVL1 gave the lowest performance.Variety Boreda-1 also gave the highest gross benefit of 47624.22 ETB and the highest net benefit of 46749.22 ETB. But the lowest gross return and net return were obtained from variety NVL-1 ,with 40044.38 ETB and 39169.38 ETB, respectively. The increasing rates of phosphorous fertilizer showed substantial improvement in nodules dry weight plant-1 , shoot dry weight plant-1 , plant height, grain yield, and biological yield up to fertilizer rates of 46 kg P2O5 ha-1 . Application of 46 kg P2O5 ha-1 recorded the highest gross income of 47053.13 ETB and net return of 45003.13 ETB and the lowest values were recorded from the control; which were 40280.63 ETB and 40280.63 ETB in that order. From the study,the interaction of variety Boreda-1 with phosphorous fertilizer rates of 46 Kg P2O5 ha-1 recorded highest gross income of 50321.25 ETB and net return of 47396.25 ETB .While, the lowest was recorded from the interaction of variety NVL-1 with phosphorous fertilizer rates of 0 Kg P2O5 ha-1 with a gross income of 36303.75ETB and net return of 35428.75 ETB. Accordingly,variety Boreda-1 and application of 46 kg P2O5 ha-1 ,can be used to improve productivity of mung bean in the study area.
RESPONSE OF BARLEY (Hordeum vulgare L.) GENOTYPES TO INORGANIC FERTILIZER TYPES UNDER ACIDIC SOIL OF HAGERESELAM, SOUTHERN ETHIOPIA
(Hawassa University College of Agriculture, 2020) HAILU HAMESO
Barley is one of the most important cereal crops in the world. It is a staple food grain, especially for Ethiopian highlanders. However, the barley productivity is commonly influenced by different biotic and abiotic factors. Soil acidity is one of the main environmental factors affecting growth and crop yield. Field experiment was conducted on acidic soil of Hagereselam, southern Ethiopia in 2019 cropping season to evaluate the performance of barley genotypes in terms of yield and yield components under different inorganic fertilizer types. The experiment was laid out in Randomized Complete Block Design with factorial arrangement with three replication and consisted of four fertilizer types (control, NP, NPS and NPSB) and four barley genotypes (217176b, 240478, 234911b and 208855b) and one barley variety (HB- 1307) as a check. Both main and interaction effects influenced days to physiological maturity, plant height, number of effective tillers m -2 , above ground total biomass and grain yield. However, days to heading, spike length, number of grain per spike, 1000 grain weight, straw yield and harvest index were only affected by main effects. Barley Genotype 217176b with NPSB fertilizer exhibited the highest grain yield of (4.9 ton ha -1 ). However, it did not significantly differ from the yield obtained from the same genotype under NP (4.72 ton ha -1 ) and genotype 240478 with NPSB fertilizer application (4.58 ton ha -1 ). The lowest yield was recorded from genotype 208855b with control fertilizer. Genotypes 217176b and 240478 were categorized as efficient and responsive to fertilization under the evaluation. The highest marginal rate of return (MRR %), 3745.35, recorded from the application of recommended rates of NPSB fertilizer for genotype 217176b. Greater net benefits with more than the minimum acceptance value of 100% of MRR were obtained for the same genotype with NP. Similarly economically acceptable performances were obtained for genotype 240478 either with NPSB or NP fertilization. Given the fact that grain yield performance between the two genotypes in combinations either with NPSB or NP is not statistically significant, either of the two genotypes with the NPSB or NP fertilizer can be recommended for barley production in acidic soils of Hagereselam and acidic soils of similar agro-ecologies in the highlands of Ethiopia. Further studies that are replicated at least over seasons are needed to investigate response of the two promising barley genotypes to application of inorganic fertilizers under acidic soil conditions in order to come up with a conclusive recommendation.
DIVERSITY OF CULTIVATED AND WILD YAMS (Dioscorea spp) IN SOUTHWEST ETHIOPIA BASED ON FARMERS MANAGEMENT PRACTICES, AGRO-MORPHOLOGICAL TRAITS AND NUTRITIONAL COMPOSITION
(Hawassa University College of Agriculture, 2021) TSEGAYE BABEGE WOROJIE
DIVERSITY OF CULTIVATED AND WILD YAMS (Dioscorea spp) IN SOUTHWEST ETHIOPIA BASED ON FARMERS MANAGEMENT PRACTICES, AGRO-MORPHOLOGICAL TRAITS AND NUTRITIONAL COMPOSITION Yam (Dioscorea spp) is a traditional crop that has long been cultivated in Ethiopia as a co-staple crop. Several yam species might have their origin in Ethiopia and are among those crops with wild relatives in the country. Though the genus Dioscorea is reported to show a wide range of variation, it has not been studied across its range of distribution. This study was investigated the diversity of wild and cultivated yams in Bench-Sheko and Sheka Zones, Southwest Ethiopia. Toward this effort, 5 studies were carried out. The first 2 studies were designed to investigate folk biosystematics, diversity and distribution and the local management practices of yams in Southwest Ethiopia. In the third study, accessions from South and Southwest Ethiopia were considered to investigate the diversity of yams based on agro-morphological traits. In the fifth study, we link two data sets to assess the knowledge of wild yam and the process of domestication. Lastly, we analyze the nutritional compositions based on selected yam landraces. We also have another study which is underway and was part of our initial project initiated with the objective of studying the true genetic diversity of yams using SSR marker. An ethnobotanical survey was conducted on 15 Kebeles in 5 districts of Bench-Sheko and Sheka Zones from Dec., 2016 to Nov., 2017. Data were collected using a semi-structured questionnaire from 272 households. Seventy-five yam accessions corresponding to 30 differently named landraces were used for morphological study. Sixty of the 75 accessions were collected in Kaffa, Bench-Sheko and Sheka Zones of Southwest Ethiopia. The rest represented previously collected accessions from Basketo, Gamo-Gofa and Wolaita areas of Southern Ethiopia. They were grown in RCBD with 2 replicates in 2018 at Hawassa University research field. The process of wild yam manipulation in Southwest Ethiopia was studied by linking two data sets derived from (1) ethnobotanical survey using 231 interviews and (2) morphological study using 47 selected accessions. Twelve landraces composed of different species and contexts were analyzed for nutritional composition in Addis Ababa at the Ethiopian Health and Nutrition Research Institute. Results obtained from ethnobotanical study suggest that there exists a systematic and welldeveloped folk naming and taxonomic system in Sheko and its environs. Sheko and Bench botany of yam recognizes 58 named individuals. These individuals are grouped into 3 well recognized ranks, namely sub-variety, variety and supra variety. Taxa assigned to each ranks have distinct features that mark them as members of a separate group. Farmers manage a wide range of morphological characters and some other attributes other than morphological ones for grouping of the taxa assigned to distinct groups. An account of each of these aspects and its link with the taxa recognized in the domain of formal science are presented. A folk biological classification of yam consisting of 4 taxonomic ranks is proposed. Our result showed much information of biological and functional aspects which can aid the taxonomic and genetic study of yams in Ethiopia. Our assessment also showed that there exists a wide range of yam diversity in Southwest Ethiopia. Altogether, 40 actually grown yam landraces, including those found in farms of unsampled households were recorded; making Bench-Sheko and Sheka Zones an area of notably high landrace diversity. The greatest number of these individuals had a narrow xviii distribution and low abundances, with a few being cosmopolitan. This was evident in a positive and significant correlation between distribution and local abundance, such that a few cosmopolitan landraces were locally more abundant. Maintenance and distribution range of landraces is related with the local management practices. A description of farmers’ decisions to the on-farm landrace maintenance is presented and implication for the collection and conservation of yam germplasm are suggested. Morphological diversity study based on 37 qualitative and 13 quantitative traits has shown a considerable variability among accessions of yam species studied. Our multivariate analysis showed that all the traits used were useful for capturing the variability among accessions, but 21 traits (17 of which are qualitative traits) were useful for capturing the variability among accessions of distinct species. The remaining traits were useful for capturing the variability among accessions within and between species, which could be exploited, if improvement need arises. The overall structure of morphological diversity is consistent with the locally perceived biota. Yet, no clear morphological variations were obtained among some differently/similarly named landraces, suggesting the need for DNAbased studies to show the full extent of the existing diversity. The observed manipulations of wild growing yams in Southwest Ethiopia suggest that yam domestication is still an active process. Knowledge of domestication was shared by 44% of the farmers, even by those that had never practice it. Farmers who have recent transplants in their garden varied from 4% in Bench to 10% in Sheko. The duration of domestication can take up to 6 years, but with most of the individuals it only takes 3 to 5 years. By linking two types of evidences, two divergent adaptation processes are distinguished: (1) parents of recent domesticate expressing a domestication syndrome belongs to wild D. abyssinica or D. praehensilis, and (2) populations of incipient domesticate that might be derived from feral or diverse types of hybrids. A description and analysis of each of these processes and their role on the adaptation process of yams is presented. Based on this account, the term adoptive transplantation is proposed to replace domestication. Although only a few landraces were used, a considerable variability existed in nutritional compositions among the studied samples. The results of nutritional study showed that landraces from D. alata contained high amounts of crude fat and ash contents that make them a good source of energy and minerals. Landraces from the D. cayenensis complex contained low moisture content that makes them suitable for prolonged storage and processing. The variability observed both among different species and among landraces in a single species highlights their potential in future breeding. More generally, this PhD study documented a great wealth of knowledge on distribution, the level of diversity within the yam, the taxonomic status, folk biosystematics and the local management practices. This constitutes an essential step towards setting development priorities and for enhancing the traditional yam farming in the studied areas. This study thus form an important part of an ongoing study aimed at designing an effective collection and conservation strategies for efficient utilization in future yam improvement.
Improving the Inclusion of Animal Source Foods in Diets for Better Nutritional Status of Women and Children: A Longitudinal Study
(Hawassa University College of Agriculture, 2021) Alemneh Kabeta Daba
Animal source foods (ASF) contain quality nutrients important for growth, development, immunity and behavioral outcomes. Plant based foods also provide the nutrients, but with lower bioavailability than ASF. Evidence on household level ASF consumption frequency, constraints and determinants are limited for Ethiopia. Therefore, this study aimed to assess consumption frequency of ASF, and to identify predictors and constraints among rural households in Ethiopia. A crosssectional study was conducted in 422 households. Consumption frequency of ASF was assessed using a food frequency screener over 30-days. Twelve statements with likert scale responses were used to identify constraints to ASF consumption. Ordinal logistic regression was used to identify determinants of ASF consumption. About a quarter (26%) of the households consumed milk 1-2 times/week. One out of five households consumed eggs 1-2 times/week (20%) or 1-2 times/month (19%). Poultry and meat were never consumed by 92% and 60% of the households, respectively. Unavailability, unaffordability, limited ASF consumption tradition and income generation priority from livestock rearing were constraints identified. Food insecure households were less likely to consume poultry (P =0.035), meat (P <0.001), eggs (P <0.001), milk (P= 0.035) and milk products (p. =0.005) than food secure households. Households that did not own chicken were less likely to consume eggs (P <0.001) than households that did own chicken. Households that did not own donkey were less likely to consume poultry (P =0.017) and meat (P =0.008) than households that did not own the donkey (P <0.05). Households that did not own cow were less likely to consume milk (P <0.001) and milk products (P <0.001) than households that did own cow. Households that did not produce cash crops were more likely to consume milk (p. =0.003) products than households that did produce cash crops (P <0.05). Households with more family size were less likely to consume poultry (P =0.002), meat (P =0.007) and eggs (P <0.03). Lesser household income was associated with lesser probability of meat (P <0.001), eggs (P <0.013) and milk product (P= 0.017) consumption. Hoseholds with women who never attended school are less likely to consume eggs (P =0.012) than households with women who attended school. Poor sociodemographic and economic conditions as determined by food insecurity, property ownership, income, educational achievement, family size and ASF unavailability and unaffordability contributed to lower consumption frequency of ASF by households in rural Ethiopia. Nutrition policy and programs should focus on nutrition sensitive agricultural extension, livelihood improvement and women empowerment interventions integrated with nutrition education to improve ASF consumption in rural settings.
ANALYSIS OF CLIMATE VARIABILITY AND CHANGE AND ITS IMPACTS ON WATER PRODUCTIVITY AND NUTRIENT USE EFFICIENCY OF MAIZE (Zea mays) IN THE GREAT ETHIOPIAN RIFT VALLEY BASINS
(Hawassa University College of Agriculture, 2021) FITIH ADEME MAMO
Climate variability and change are a global phenomenon affecting many nations. Smallholder farmers in Ethiopia have been facing severe climate related hazards, in particular highly variable rainfall and severe droughts that negatively affect their livelihoods. Anticipated climate change is expected to aggravate some of the existing challenges and impose new risks beyond the range of current experiences. This study aimed at understanding current climate variability and future climate change, and its associated impacts in particular for maize production. The climate analysis was conducted in the Great Rift Valley Basins (GRVB), which represents diverse agroecology and farming systems. The climate variability and change impact study were conducted in the Central part of the Rift Valley (CRV), which represent a major cereal-based farming system of the semi-arid environments of Ethiopia. Empirical statistical analyses using field experimental data in combination with crop-climate simulation modelling were used to achieve the objectives of the study. A high spatial resolution regional climate models and a well-known crop growth simulation model were used for the modelling analysis, which is an innovative feature of the methodology used in this thesis. The analysis revealed that rainfall exhibited high interseasonal variability (coefficient of variation 13-37%) during the period 1981-2010 in the GRVB. The mean annual temperature significantly increased by +0.43 ºC [0.27 ºC to 0.58 ºC] per decade in the same period. Projections for future climate suggested that annual rainfall will change by -25 to +6% and the annual temperature is expected to increase in the range of 2.5-5.1oC by the end of this century. A corresponding change in length of growing period (LGP) from -5.66 to -25.5% for central semiarid and +3.9 to -16.4% for central sub-humid highlands was simulated in the near century. Maize grain yield was strongly (P<0.01) and positively correlated with seasonal rainfall (r=0.67-0.69) in the CRV while day temperature affected grain yield negatively (r= -0.44) at Ziway (P<0.05) during the simulation period. Simulated water-limited yields showed high inter-annual variability (coefficient of variation, ~24%) and about 47% of this variability was explained by the xvii variation in growing season rainfall. The observed farmers’ yield was 28, 48 and 57% lower than the researcher-managed, water--limited and potential yield of the crop, respectively, indicating wide maize yield gap in the region. Analysis of climate change scenarios showed that maize yield will decrease on average by 16.5 and 23% by mid and end of this century, respectively due to climate change. Similarly, water productivity is expected to decline on average by 2.2 and 12% in the CRV by mid and end centuries with respect to the baseline. Nutrient uptake and corresponding nutrient use efficiency (NUE) might also be negatively affected by climate change. Phosphorus uptake probably will decrease in the CRV on average by 14.5 to 18% by mid-century. Nitrogen and P use efficiency indicators showed decreases in the range between 8.5 to 10.5% and between 9.3 to 10.5%, respectively by midcentury relative to the baseline average. The simulation under no water and nutrient limitation condition ensured improvements of both water and nutrient use efficiency in the changed climate which could ensure modest production in the future. The high estimated impact of climate variability and changes on crop yield and associated resources use in the CRV imply greater risks on rainfed crop production in the region. Hence, the study recommends further assessment of potential adaptation options and economic impact of climate related risks in the region to provide full-fledged evidence for better policy decisions.
GROWTH, SYMBIOTIC AND YIELD RESPONSES OF SOYBEAN (Glycine max L.) VARIETIES TO BRADYRHIZOBIUM INOCULATION AND PHOSPHORUS APPLICATION AT ALAGE, CENTRAL RIFT VALLEY OF ETHIOPIA
(Hawassa University College of Agriculture, 2021) AYANA YADETA GEMEDA
Soybean (Glycine max L.) is one of the most important food legumes of great nutritional value that has the highest protein content (40%) of all food crops and is equivalent to the protein of animal product. However, in Ethiopia its productivity is constrained mainly by low soil fertility and lack of improved varieties. A field experiment was conducted during 2020 belg cropping season at Alage Central Rift Valley of Ethiopia with the objective of evaluating the effects of Bradyrhizobium japonicum strain inoculation and P fertilizer rates on growth, symbiotic and yield response of soybean varieties. The treatments studied includes four P levels (0, 10, 20 and 30 kg P ha-1 ), two inoculation levels (un-inoculated and inoculated with Bradyrhizobium strain; TAL-379) and two soybean varieties (Afgat and Nova) in randomized complete block design with factorial arrangement with three replications. The results revealed that the main effect of varieties were significantly (P≤ 0.01) influenced most of measured parameters. The results also revealed that inoculation of soybean varieties with Bradyrhizobium strain TAL-379 significantly (P≤ 0.01) influenced days to maturity, nodule number, nodule dry weight, shoot dry weight, root dry weight, pod number plant-1 , hundred seed weight, grain yield, above ground biological yield and harvest index. Conversely, days to emergence, days to flowering, plant height and seed number pod-1 was not statistically affected by inoculation of strain TAL-379. The effect of P fertilizer was also significant for most of studied parameters except branch number and harvest index. The interaction effect of varieties x strain, strain x P, and varieties x P caused significant variation on days to maturity, number of nodule, nodule dry weight, shoot dry weight, root dry weight, pod plant-1 , hundred seed weight, grain yield and above ground biological yield. Hence, the use of Afgat variety with Bradyrhizobium strain TAL-379 inoculation significantly gave the highest grain yield (2.99 t ha-1 ) followed by the interaction of Afgat variety with the supply of 20 kg P ha-1 (2.89 t ha-1 ). Grain yield was positively and significantly correlated with most of studied parameters. From the economic point of view the partial budget analysis of the study treatments revealed that the highest net return (63750 ETB ha-1 ) was gained from Bradyrhizobium strain TAL-379 inoculation followed by application of 20 kg P ha-1 and Afgat variety. Thus, it could be recommended that the use of Afgat variety, Bradyrhizobium strain TAL-379 and application of 20 kg P ha-1 to get higher yield and profit of this crop at Alage Central Rift Valley of Ethiopia. However, verification of the result on farmers’ fields across season and areas could be required before wide use of this study to put the recommendation in firm ground
EFFECTS OF INOCULANT AND NPS FERTILIZER ON NODULATION, GROWTH AND YIELDS OF COMMON BEAN (Phaseolus vulgaris L.) VARIETIES AT BILATE ZURIA DISTRICT, SIDAMA REGIONAL STATE, ETHIOPIA
(Hawassa University College of Agriculture, 2021) ENJAMO NAGESSO SATO
Common bean (Phaseolus vulgaris L.) is a major grain legume grown and consumed in subSaharan Africa, including Ethiopia. It is the most important food legume, fodder and cover crop. However, its cultivation is globally constrained mainly by low soil fertility and lack of improved agronomic practices. Four common bean varieties (Ibaddo, Hawassa Dume, Omo95 and Nasir were studied under three nutrient conditions (0kg ha-1 ,100 kg ha-1 NPS, Inoculation by strain HB-429) in three replication of randomized complete block design (RCBD) during the 2019 main cropping season (June to September). The objectives of the study were investigating the response these varieties to the three nutrient statuses in nodulation, growth, yield and yield components and investigating the variety X inoculant/fertilizer interaction in the same traits. There were significant differences between the four varieties in all traits (nodulation, growth, yield and yield components). Ibaddo had the highest grain yield (2.81 t ha-1 ) while Hawassa Dume had the highest mean in yield (2.53 t ha-1 ). The three fertilizer levels also differed significantly in all traits, 100 kg ha-1 NPS giving the highest means in all traits, while the control (no fertilizer application) had the lowest mean in all traits. Inoculation by rhizobium strain had intermediate mean of all traits. The variety X inoculant/fertilizer interaction was also significant for all traits except for nodule dry weight, leaf area index, shoot dry weight, grain yield, above biological yield and harvest index. Omo95 variety had the lowest means in all traits except leaf area index, plant height, number of primary branches where ranks first, second and third. The highest net return (48325 ETB ha-1 ) with acceptable marginal rate return (5993%) was obtained from Hawassa Dume variety with 100 kg NPS ha-1 followed by Hawassa Dume variety with strain HB-429 inoculation had net return of 41337 ETB ha-1 with 4895% marginal rate of return. This implies that the grower on the study area can gate additional benefit of 59.93 and 48.95 ETB for every 1 ETB expense by growing Hawassa Dume with the application of 100 kg NPS ha-1 and strain HB-429 inoculation, in that order. Moreover, the highest net benefits (37763.5) with MRR (%) of 3084 ETB and net benefits of 3935ETB with MRR (%) obtained from variety Ibaddo and Nasir grown with strain HB-429 and 100 kg NPS ha-1 fertilizer application. Therefore, use of both Hawassa Dume and Nasir varieties with 100 kg NPS ha-1 and Hawassa Dume and Ibaddo grown with strain HB-429 found to be economically feasible at the study area. However, verification of the result on farmers’ fields across season and similar areas could be required before wide use of this study to put the recommendation in firm ground.
EFFECTS OF SEED AND BLENDED FERTILIZER RATES ON YIELD AND YIELD COMPONENTS OF BREAD WHEAT (Triticum aestivum L.) AT DUNA DISTRICT, HADIYA ZONE, SOUTHERN ETHIOPIA
(Hawassa University College of Agriculture, 2021) BIRHANU ARASO LATEBO
Bread wheat is one of the major staple and strategic food security crops in Ethiopia. However, the production and productivity of the crop are far below the global average. This is partly due to the low soil fertility and poor crop management practices including the use of suboptimal seed and fertilizers rates. Hence, this experiment was conducted to assess the effect of seed and blended fertilizer (NPSB) rates on the growth and yield of bread wheat; and determine the economically feasible seed and NPSB fertilizers rates for wheat production in the study area. Treatments consisting of four levels of seed rates (80, 100, 120, and 140 kg ha1 ) and four levels of blended NPSB fertilizers (0, 50, 100, and 150 kg ha-1 ), was laid out in a Randomized Complete Block design in factorial combinations with four replications. Data were collected on phenology, growth, and yield parameters and subjected to ANOVA using SAS software version 9.0. Results revealed that the days to heading, days to physiological maturity, plant height, spike length, thousand kernels weight, straw yield, and above-ground dry biomass were significantly (p<0.01) affected by the main effect of seed and NPSB fertilizer rates. The longest days to heading, days to physiological maturity, and spike length were recorded at 80 kg ha-1 seed rate. The maximum thousand kernels weight was obtained from the 120 kg ha-1 seed rate. However, the tallest plant height, straw yield, and above-ground dry biomass were recorded at 140 kg ha-1 seed rate. The tallest plant height, spike length, number of kernels spike-1 , thousand kernels weight, straw yield, and above-ground dry biomass were obtained from 150 kg ha-1 NPSB rate. However, the longest days to heading and days to physiological maturity were recorded from the control. The treatment interactions significantly (p<0.05) affected the number of total tillers, number of productive tillers, grain yield, and harvest index. The highest number of total and productive tillers were recorded at the combination of 140 kg ha-1 seed rate with 150 kg ha-1 NPSB fertilizer rate. However, the highest grain yield and harvest index were recorded from the combination of 120 kg ha-1 seed and 150 kg ha-1 NPSB fertilizer rates. Grain yield was strongly and positively correlated with plant height, number of total tillers, number of productive tillers, number of kernel spike-1 and above-ground dry biomass. As per the partial budget analysis the highest net benefit of 81,914 ETB ha-1 was obtained from the combined application of 120 kg ha-1 seed rate with 150 kg ha-1 NPSB fertilizer with a MRR of 988.2%. Hence, the combination of 120 kg ha-1 seed and 150 kg ha-1 NPSB fertilizer rates are profitable than other combinations, therefore this combination can be recommended for wheat production in the Duna District and areas sharing similar agro-ecology.