YIELD AND WATER PRODUCTIVITY OF TOMATO UNDER FULL AND DEFICIT IRRIGATION IN NORTHERN NIGERIA

Abstract

The study was conducted using two field experiments at the Institute for Agricultural Research (IAR) irrigation site, Kadawa, Kano State, Nigeria during the 2016/2017 and 2018/2019 irrigation season. The main aim of the study is to determine yield and water-use
responses of tomato (UC 82B) crop to full and Deficit Irrigation Practice (DIP) and also to determine the optimum crop water requirement of tomato in Sudan Savannah agroecological zone of Nigeria. The experiment consisted of nine irrigation treatments and was carried out using a Randomized Complete Block Design (RCBD) with three replications. Furrow irrigation method was employed for water application. The treatments were based on water application regulated at selected crop growth stages. The growth stages were Initial (I), Development (D), Middle (M) and Late (L) and the irrigation deficit level were 0, 25 and 50%. The treatments were T1 (I₁₀₀D₁₀₀M₁₀₀L₁₀₀), T2 (I₁₀₀D₅₀M₁₀₀L₁₀₀), T3 (I₁₀₀D₁₀₀M₅₀L₁₀₀), T4 (I₁₀₀D₁₀₀M₁₀₀L₅₀), T5 (I₁₀₀D₇₅M₁₀₀L₁₀₀), T6 (I₁₀₀D₁₀₀M₇₅L₁₀₀), T7 (I₁₀₀D₁₀₀M₁₀₀L₇₅), T8 (I₁₀₀D₅₀M₅₀L₅₀) and T9 (I₁₀₀D₇₅M₇₅L₇₅). The result from the two experiments showed that the yield of tomato is significantly affected by water stress. The mean fresh tomato yield varied from 72.52 t/ha to 40.81 t/ha. The highest mean yield of 72.52 t/ha was obtained in the control treatment T1 (I₁₀₀D₁₀₀M₁₀₀L₁₀₀) which was subjected to full irrigation, whereas the least mean yield of 40.81 t/ha was obtained in the fully stressed treatment T8 (I₁₀₀D₅₀M₅₀L₅₀). The development- and middle growth- stages of tomato crop were highly sensitive to water stress particularly at 50% deficit level (DL), while late growth-stage of the crop was less sensitive to water stress particularly at both 50% and 25% DL. Imposing DL of 25% at development growth-stage resulted in yield reduction of 7%, while imposing DL of 50% at the three (development, middle and late) growth-stage of tomato resulted in yield reduction of 44%. The optimum seasonal water requirement for tomato crop in Sudan Savannah agroecological zone of Nigeria was 554 mm. Also, for optimum yield and irrigation water productivity of tomato crop under DIP, imposition of 25% deficit level in the late growth stage
was recommended.