College of Agriculture
Permanent URI for this communityhttps://etd.hu.edu.et/handle/123456789/40
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.
News
Latest research publications, theses, and academic resources from the College of Agriculture are now available.
Browse
2 results
Search Results
Item ASSESSMENT OF WEED SPECIES COMPOSITION AND THEIR MANAGEMENT PRACTICES IN ONIONAND EFFECT OFDIFFERENT WEED CONTROL METHODS IN ONION (Allium cepaL.)IN THE CENTRAL RIFT VALLEY OF ETHIOPIA(Hawassa University College of Agriculture, 2019) FEYISA BEKELE JIMAFarmers have lack of awareness on weed problem on the crop and under take only manual weeding option to control those weeds in their fields. The study identified weed species composition and their management practices in onion (Allium cepa L.) fields of Adami Tulu, Dugda, Lume, and Around Adama woradas, Central Rift Valley of Ethiopia. In addition the effect of different weed control methods in onion were evaluated in Meki woreda during 2017/2018 under irrigation. Primary data were collected from 200 individual farmers using structured questionnaires, face to face interview. Secondary data were collected from different literatures and reports, and analyzed using descriptive statistics, using SPSS version 20. Weed species compositions were determined in a quadrat count of 0.5m2 using systematic sampling techniques to obtain representative sample in the fields. The identified individual weed specieswere analyzed using quantitative means. Identified most problematic weed families wereAsteraceae (16 spp.), Poaceae (10 spp.), Solonaceae (2 spp.),Cyperaceae (2spp.)in descending order of 1st, 2nd, 3rdand4rd abundant weed families, respectively.The experiment was contained 13 different weed control treatments and laid down in randomized complete block design with four replicates. Collected data were analyzed using SAS version 9.0. The weed density varied significantly with the treatments (P<0.05). At 60 DAT the lowest weed density (41.875/m2) was recorded under HW3WAT followed by Oxyflourfen at 0.5L/ha + HW6WAT. At harvest the lowest weed density (30.875g/m2) was obtained under Oxyflourfen at 0.5L/ha+HW6WAT. The lowest weed dry weight was recorded from Pendimethalin at 1.5L/ha+HW9WAT (293.27g/m2). The highest weed controlefficiency(82.15%) was recorded under Pendimethalinat 1.5L/ha+HW9WAT followed by Oxyflourfen at 0.5L/ha+HW9WAT (80.48%) after weed free plot.The maximum plant height (43.47cm) was recorded in weed free plot followed by Oxyflourfen at 0.5L/ha+HW3WAT (40.68cm). But the number of leaves per plant has shown no significant difference with respect to different treatments (P>0.05). Maximum bulb diameter, bulb weight, bulb size (3.51cm, 122.58g, 73.25ml, 29.62ton/ha) were recorded respectively from weed free plot, which were statistically non-significant from Oxyflourfen at 0.5L/ha+HW9WAT). The lowest loss in yield (0.03%) was recorded in weed free check followed by plot treated with oxyflourfen at rate of the 0.5 L/ha + HW6WAT (6.8%) as compared to the highest yield obtained in plot treated with oxyflourfen at rate of the 0.5 L/ha + HW9WAT. Weed free check plot resulted in higher cost of protection and gross return but lower in net return and benefit: Cost ratio, whereas Oxyflourfen at 0.5L/ha and pendimethalin at 1.5L/ha showed highest Benefit: Cost ratio (20.34 and 14.65) respectively. The study showed that using herbicides alone or in combination with hand weeding is highly profitable than using hand weeding alone. Future studies on the use of herbicides with different rates and combinations with other methods, critical period of weed-control and more survey works in different onion production agro-ecologies are recommended.Item 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 WASIEOnion 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.
