Selection of shade-tolerant tomato genotypes

Abstract: Tomato genotypes exibit different shade intolerance and shade-tolerant tomatoes have potential for vegetable-agroforestry system. To obtain shade-tolerant tomatoes, a study on several tomato traits were evaluated on their morphological and physiological characteristics and their yield as responses to low light intensity. This experiment was conducted at farmer’s field, Bogor (October 2014-February 2015) using nested factorial design with three replications. Study was conducted on 50 tomato genotypes cultivated under 50 and 100% light intensity. Variables observed were: leaf number and area, flower number, fruit number, fruit weight and production, flowering and harvesting time. The tolerance levels of tested genotypes were classified based on plant relative productivity rate. Analysis of variance was used to differentiate between genotypes within response group; principal component analysis to define variance characters between genotypes; and cluster analysis using Euclidean distance method to determine relationship among tomato genotypes and similarity level . The 50 genotypes under shading condition were classified into 5 shade-loving genotypes, 16 shade-tolerant genotypes, 15 shade-moderately-tolerant genotypes and 14 shade-sensitive genotypes. First two principal components explained 57.19% variation. The first principal component was plant production and reproduction with the value of 37.69%; and the second one was plant morphological characters with the value of 19.50%. The dendrogram from cluster analysis separated 50 genotypes to 3 clusters with a distance of 20. There were 7 genotypes in the first cluster, 11 genotypes in the second cluster; and 32 genotypes in the third cluster.