Agricultural and Biological Research

Effect of mulch levels and irrigation deficit on onion ( Allium cepa L. ) yield and water productivity

Nuru Seid Tehulie*

In water-scarce locations like the Rift Valley, increasing the water productivity of irrigated vegetation through agricultural water management is a critical choice. As a result, a subject study was carried out at Gewane Agricultural TVET College to assess the effects of deficit irrigation and straw mulching on onion yield, productivity, and water productivity (Allium cepa L). In three replications, the experiment was put out in a randomized complete block design with a factorial arrangement of three levels of irrigation (a hundred, eighty, and sixty percent of and others) and four ranges of straw mulch (0, 3, 6, and 9 ton wheat straw per ha). The Crop Wat model output revealed that the highest seasonal water need of onion was 422.5 mm at 100% ETc, while the lowest was 253.5 mm at 60% ETc. The analysis of variance revealed that there was a statistically significant (p<0.05) difference in growth parameters, and yield parameters were shockingly large (p<0.01) when the interaction results of deficit irrigation and straw mulch ranges were used. The highest marketable bulb yield (33.47 t/ha) was obtained from an experimental plot treated with a combination of 100 percent and 6 t/ha straw mulch, while the lowest (21.10 t/ha) was obtained from plots treated with 60 percent and no mulch treatment. The interaction results of deficit irrigation and straw mulching levels inspired enormously vast water productivity (p<0.01); the highest (10.22 kg/m³) and lowest (6.11 kg/m³) were recorded from plots treated with 60 percent ETc and 9 t/ha straw mulch, and 100 percent and many others and no mulch treatments, respectively. According to a partial budget analysis, the most economically advantageous combination for small-scale farmers with reduced production costs and better net benefits was the application of 80% ETc and 6 t/ha straw mulch. As a result, irrigating with 8% with 6 t/ha straw mulch would be recommended for onion production in the study region in terms of marketable bulb yield and water profitable productivity.