Performance Evaluation of Sesame under Regulated Deficit Irrigation Application in the Low Land of Western Gondar, Ethiopia

Abstract

Sesame (Sesamum indicum L.) is the leading oil seed crop produced in Ethiopia. It is the second most important agricultural commodity for export market in the country. It is well suited as an alternative crop production system, and it has low crop water requirement with moderate resistance to soil moisture deficit. The low land of North Western Ethiopia is the major sesame producer in the country, and the entire production is from rainfed. The rainfall distribution in North Western Ethiopia is significantly varied. This significant rainfall variability hampers the productivity of sesame. Irrigation agriculture has the potential to stabilize crop production and mitigate the negative impacts of variable rainfall. This study was proposed to identify critical growth stages during which sesame is most vulnerable to soil moisture deficit and to evaluate the crop water productivity of sesame under deficit irrigation. The performance of sesame to stage-wise and uniform deficit irrigation scheduling technique was tested at Gondar Agricultural Research Center (Metema Station), Northern Western Ethiopia. Eight treatments, four stage-wise deficit, two uniform deficit, one above optimal, and one optimal irrigation applications, were evaluated during the 2017 irrigation season. The experiment was designed as a randomized complete block design with three replications. Plant phenological variables, grain yield and crop water productivity, were used for performance evaluation. The result showed that deficit irrigation can be applied both throughout and at selected growth stages except the midseason stage. Imposing deficit during the midseason gave the lowest yield indicating the severe effect of water deficit during flowering and capsule initiation stages. When deficit irrigation is induced throughout, a 25% uniform deficit irrigation can give the highest crop water productivity with no or little yield reduction as compared with optimal irrigation. Implementing deficit irrigation scheduling technique will be beneficial for sesame production. Imposing 75% deficit at the initial, development, late season growth stages or 25% deficit irrigation throughout whole seasons will improve sesame crop water productivity.

Determination of yield response factors for different varieties of teff

“…As reviewed for different crops other than teff, the most sensitive growth stage to water stress is the yield formation growth stage or mid‐growth stage. In line with this, the highest yield was reduced due to water stress or deficit irrigation at the mid‐growth stage for sesame crops (Mekonnen & Sintayehu, 2020). The fruit growth and flowering stages are the most sensitive periods in relation to irrigation water deficit and yield loss for citrus crops (Tejero et al, 2012).…”

Interactive effect of irrigation strategies and mulching on yield, water use efficiency and crop response factor of maize (Zea mays L.) in a semiarid climate

“…This relationship may reflect a remarkable validity and allowable procedure for quantifying the impact of water deficit on economic yield. (Mekonnen and Sintayehu, 2020). Therefore, relative yield reduction was less than the relative evapotranspiration deficit when deficit irrigation scheduling was induced over the whole stage of growth.…”

Relationship of Maize Yield to Climatic and Environmental Factors under Deficit Irrigation: A Quantitative Review

“…Nineteen (19) peerreview papers published in English were selected based on the selection criteria mentioned in the above section. In total, 653 data points were collected before averaging across replicates under the same water stress levels and growth stages.…”

“…Te sensitivity of a plant's growth stage to water stress can also be afected by many factors, including climatic conditions, crop species, and cultivars, agronomic management practices, among others [17]. Various studies pointed out the reproductive stage as the most sensitive to water stress in major food crops [18][19][20][21].…”