Institute of Technology

Permanent URI for this communityhttps://etd.hu.edu.et/handle/123456789/66

The Institute of Technology focuses on education, research, and innovation in engineering, technology, and applied sciences to support sustainable development.

Browse

Subject: search.filters.subject.Water productivity

Search Results

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    EFFECT OF DEFICIT IRRIGATION ON YIELD AND WATER PRODUCTIVITY OF ONION (Allium cepa L.) UNDER CONVENTIONAL FURROW IRRIGATION SYSTEM IN BENNATSEMAY WOREDA, SOUTHERN ETHIOPIA
    (Hawassa University, 2019-10-22) TADESSE MUGORO LEBISO
    Enhancing water productivity is an important strategy for addressing future water scarcity in arid and semi-arid regions. Hence, innovations are needed to increase the water use efficiency that is available. Deficit irrigation is believed to improve water productivity without causing severe yield reductions; which the crop is exposed to a certain level of water stress either during a particular period or throughout the whole growing season. The field experiment was conducted in Bennatsemay Woreda Weyito experimental site of Jinka Agricultural Research Center, Southern Ethiopia, during 2018 season with objective of investigating the effect of deficit irrigation on yield and water productivity of Onion under conventional furrow irrigation system. Six treatments (T1=100% ETc, T2=85% ETc, T3=70% ETc, T4=50% ETc, T5=100% ETc Is, 85% ETc Ds, 70% ETc Ms, 50% ETc Ls and T6=85% ETc Is, 70% ETc Ds, 50% ETc Ms, 0% ETc Ls) were imposed on Onion (Allium cepa L.) Bombay red variety and laid out in randomized complete block design (RCBD) with four replications. Results indicated that the different deficit irrigation levels had highly significant (p < 0.01) effect on vegetative growth, yield, yield components and water use efficiency of Onion. Onion bulb yield was reduced with increased water stress, where as water productivity was increased with stress level increased. The highest bulb yield of 21.3 t/ha were obtained from T1 which was significantly different to all other treatments while yield from T6 (12.86 t/ha) was recorded as the lowest one. Similarly, the highest IWUE (2.41 kg/m3 ) and CWUE (4.02 kg/m3 ) were obtained from T6 which was significantly superior to all other treatments. But, at T4 and T6 high yield reduction was recorded which may not be attractive for producers. On the other hand, the total bulb yield, yield components, IWUE and CWUE observed under T3 and T5 irrigation application levels had no statistically significant variation (p < 0.01). However, under T5 the relative yield reduction was greater when compared to T3. So, instead of T5, using T3 (applying 70% ETc) is advisable. Accordingly, made T5 out of the role, compared T1, T2, T3, T4 and T6, high IWUE was observed under T6 and T4 with high yield reduction penalty. From resources conservation point of view, maximum water productivity may be our attention, which could be obtained under this severe deficit irrigation. However, such consequences on yield may not be tolerable from producers view point (at T4 and T6). Therefore, it could be concluded that increased water saving and water productivity through irrigation at 70% ETc deficit irrigation level under conventional furrow irrigation system can solve the problem of water shortage and would ensure the opportunity of further irrigation development in the study area and similar agro-ecology
  • No Thumbnail Available
    Item
    RESPONSE OF ONION( Allium Cepa L, )TO DIFFERENT IRRIGATION LEVELS UNDER DRIP AND CONVETIONAL FURROW IRRIGATION WITH AND WITH OUT MULCH AT MELKASSA , CENTRAL RIFT VALLEY OF ETHIOPIA
    (Hawassa University, 2020-10-26) GEBEYEHU ASHEMI BIKILA
    Water is a scarce resource in Central Rift Valley of Ethiopia and is a major limiting factor for crop production. Onion is one of the major economically important vegetable crops grown under irrigation in central rift valley. The field experiment was conducted at Melkasa agricultural research center during the dry season to identify irrigation method and irrigation application level with and whithout mulch that maximizes productivity of onion per unit of water consumed and enhanced onion crop production. The experiment was carried out using split plot design inRCBD having twelve treatments with three replications.The FAO’s recommended allowable Manageable depletion level of onion is 25%. In this study 75%, 100% recommended and 125% were tested. The experiment consisted of two irrigation methods viz.,furrow irrigation and drip irrigation as main plot and three levels of Manageable allowable depletion viz., 125%, 100% and 75% with and whith out mulch as sub-plot.The analysis of variance revealed that irrigation methods and management allowed depletion levels had a significant (p<0.01 and p<0.05) effect on onion vegetative parameters like plant height, leaf height and yield parameters like bulb diameter, bulb height, total bulb yield, marketable bulb yield, and water productivity. The highest and lowest onion vegetative and yield parameters were obtained from drip irrigation and furrow irrigation method, respectively. Moreover, the highest and lowest onion vegetative and yield parameters were obtained from drip irrigation under 75% MAD with mulch and furrow irrigation under125% MAD without mulch, respectively. Further, their interaction had a significant effect on total bulb yield and water productivity. Nonetheless, they had no significant effect on number of leaves per plant, plant height, leaf height, bulb diameter, marketable bulb yield and bulb height.The maximum total bulb yield (37.1 ton/ha), marketable bulb yield (33.1 ton/ha), bulb diameter (5.6 cm), crop water use efficiency (0.78 kg/m3 )and irrigation water use efficiency, (0.60 kg/m3 ) were observed from drip irrigation method at 75% MAD with mulch application, while significantly lower as (30.5 ton/ha), (26.7 ton/ha), (5.0 cm), (0.53 kg/m3 )and (0.40 kg/m3 ) respectively were recorded from furrow irrigation method at 125% MAD with out mulch application. Generally, drip irrigation was working efficiently according to its design and economically acceptable. Among all tested treatments drip irrigation method under 75% MAD with mulch was the best practice because of its high yield and water productivity
  • No Thumbnail Available
    Item
    RESPONSE OF ONION (Allium cepa L.) TO DEFICIT IRRIGATION UNDER SURFACE AND DRIP IRRIGATION METHOD IN CENTRAL RIFT VALLEY OF ETHIOPIA
    (Hawassa University, 2019-10-25) BENIAM YAZIZ MUKTAR
    Onion (Allium cepa L.) is the most important and widely cultivated vegetable crop in the Central Rift Valley of Ethiopia. However, available water resources are the most limiting factor for crop production in the area. A field experiment was conducted on loam soil at the experimental farm of Melkass agricultural research center, Ethiopian Institute of agriculture research with the objective of evaluating the effects of irrigation method and deficit irrigation on yield and water use efficiency of onion. The experiment consisted of two irrigation methods (Drip and furrow) and four deficit irrigation levels (85%ETc, 70%ETc, 60%ETc, and 50%ETc) and control irrigation of 100%ETc and laid out using split plot design in RCBD with three replication. Irrigation methods were used as the main plot and the five irrigation levels as sub-plot. Irrigation water was applied at allowable soil moisture depletion (p=0.25) of the total available soil moisture throughout the crop growth stage. The study has shown a highly significant (P ≤ 0.01) difference on yield, yield parameters and water productivity of onion. The highest total onion bulb yield (52.1t/ha) was obtained from applying 100%ETc under drip irrigation method and had no significant difference with drip irrigation at 85%ETc irrigation application. Onion bulb yield decreased with an increase in levels of water deficit. Both water productivity and irrigation water productivity increased with increase in water deficit level. The highest water productivity and irrigation water productivity were obtained under furrow and drip irrigation, respectively. Deficit irrigation application of 85%ETc, 70%ETc and 60%ETc under drip method apparently gave a non-significant difference for most yield attributes. Among furrow irrigation techniques, the highest onion yield (43.4t/ha) was obtained from convention furrow irrigation with 100% ETc irrigation application and the highest water productivity and irrigation water productivity were observed in alternate furrow irrigation at 70%ETc irrigation application. Hence, under Melkassa climatic condition, onion could be irrigated under drip and alternate furrow irrigation method at 70%ETc deficit irrigation applications considering the availability of water resources and crop water productivity