Effect of gypsum application on yield performance of groundnut (<em>Arachis hypogea</em> L.) Varieties in Kilinochchi district, Sri Lanka

Abstract

Groundnut (<em>Arachis hypogea </em>L.) is an important oil crop grown in Sri Lanka. Application of fertilizer is substantially contributing to the yield increment; however improper management of fertilizer is the specific drawback in quality and quantity in groundnut. Therefore, the application of balanced fertilizer and minerals play an important role in the cultivation of groundnut. An experiment was conducted at the Department of Agronomy, Faculty of Agriculture, Kilinochchi to assess the effect of different rates of gypsum application on yield performance of groundnut varieties from January to May 2019. Two-factor factorial experiment was conducted in Randomized Complete Block Design (RCBD) with three replications. Four different rates of gypsum application such as 0 kg/ha (T₁ - Control), 75 kg/ha (T₂), l25 kg/ha (T₃), and 175 kg/ha (T₄) were used as the first factor and five groundnut varieties, namely Tissa (V₁), Lanka Jumbo (V₂), Tikiri (V₃), Indi (V₄), and ANK G1 (V₅) were used as the second factor. All the agronomic practices were done according to the recommendations of the Department of Agriculture. The yield parameters were recorded, and the shelling percentage was calculated. Data were analyzed using SAS 9.1 package to perform ANOVA. The best treatment was identified through the means separation using Duncan’s Multiple Range Test (DMRT) at p = 0.05. The yield parameters of fresh and dry weight of pods / plant, hundred pods and seeds weight, number of mature and immature pods and total yield were higher in gypsum appliedtreatments rather than control and the highest in T₄ (175 kg/ha gypsum) treatment. All the yield parameters were significantly different in Lanka Jumbo and ANK G1 from other varieties. However, the number of mature pods and shelling percentage were similar among the varieties. The highest shelling percentage (96 %) was recorded in Lanka Jumbo under 175 kg/ha gypsum application (T₄). The highest yield parameters were recorded in Lanka Jumbo variety, whereas the lowest was in ANK G1. There was no interaction effect among gypsum application and varieties in the yield parameters. From this study, it can be concluded that the application of 175 kg/ha gypsum (T₄) to the variety of Lanka Jumbo (V₂) can be selected as suitable treatment combination to obtain the substantial yield from groundnut in <em>Yala </em>season.