EXPLORING GENETIC VARIABILITY IN TOMATO GENOTYPES (SOLANUM LYCOPERSICUM L.) USING AGRO-MORPHOLOGICAL AND POLYMORPHISM ANALYSIS OF LYCOPENE BIOSYNTHETIC GENES

Abstract

The agro-morphological assessment showed that different generations created different genetic characteristics which affected essential yield and quality measurements. The study found that phenotypic traits showed high similarity to genotypic traits because environmental factors had minimal impact on their development. The study found that yield and fruit weight and locule number traits showed high variability together with their strong inheritance patterns which made them suitable for selection during early breeding generations. The study found that direct phenotypic selection achieved high success because major yield traits showed both high heritability and substantial genetic progress which divided gene effects between additive and non-additive pathways. The study found that all qualitative traits except fruit colour maintained their stability across multiple generations while one mutant line showed a marked change in fruit colour which resulted from specific mutations that affected pigment production. The study confirmed that key genes in the carotenoid pathway undergo EMS-induced mutations which include changes to the lycopene β-cyclase gene. The research showed that nucleotide substitutions resulted in protein alterations which affected essential sections of the protein thus diminishing enzyme function and causing increased lycopene production. Phylogenetic analysis confirmed that treated lines and control lines had separate lineages because both groups had mutations which could be passed down through generations. The research proved that EMS mutagenesis created useful genetic variations which scientists used to conduct genetic and molecular studies. The identified mutant lines serve as valuable genetic materials for breeding programs which aim to develop tomato cultivars with high yields and elevated lycopene content.