Research Articles


Genetic variation in agronomic traits and yield performances of tomato (Solanum lycopersicum) genotypes in response to heat stress


Kim Sreang DY, Sophoanrith RO*, Siranet ROEURN, Sreymey NGOUN, Leangsrun CHEA, Penghieng THEAM, Sathya LIM, Rathana SOR, Malean ROEUN, Kosal MEAS

Faculty of Agronomy, Royal University of Agriculture, Phnom Penh, Cambodia
*Corresponding author: rsophoanrith@rua.edu.kh 

Abstract

High temperature is one of the most unfavourable factors which affects biochemical, morphological, and physiological facets of tomato, decreases normal growth and subsequently reduces the crop yield. The optimal daily mean temperature for tomato fruit set under field conditions is between 21 and 24 oC. While Cambodia has high temperature in a couple of months (e.g. March-May) up to 38oC, resulting in low productivity or even no production of tomato available during this period. The aim of this study was to investigate the performance of various tomato genotypes under high temperature between March-May 2018. Eight tomato lines (CLN3736D, CLN3078G, CLN3212C, CLN3024A, CLN2498D, CLN3125L, CLN1621, CLN2026D) and two local varieties as check varieties (KK1 and Neang Tamm) were selected for the study. The highest temperature during the trial was up to 38oC with an average day temperature of around 30°C. This experiment was conducted in the open field of crop station (sandy loam) at the Royal University of Agriculture and was laid out in a Randomized Complete Block Design (RCBD) with three replications. The results showed that (KK1) had the highest total fruit yield (795.01g plant-1) followed by CLN1621L (586.99g plant-1) and CLN3212C3 (454.94g plant-1). Moreover, CLN1621L produced the highest number of fruits per plant (23fruits plant-1) followed by KK1 and CLN3212C3 with 10.84fruit plant-1. Based on this study, KK1, CLN1621L and CLN3212C performed the best during this high temperature span. Further study on agronomic practices such as crop rotation, pest controls, grafting, etc. should be investigated to enhance the productivity of these potential genotypes. Fruit size preference should also be considered to select potential genotypes for commercial purposes.

Keywords: Tomato genotypes, agronomic performance, heat tolerance.