Characterization of tomato germplasm accessions for breeding research

Although tomato is the leading vegetable crop in Kenya, not much work has been done to develop improved tomato varieties with farmer preferred and market demanded traits. This study aims to characterize ten tomato genotypes for morphological and agronomic traits and to identify potential parental lines for use in the breeding program. The experiments were conducted in Kenya during the 2017 long and short rain seasons. Trials were laid out in a randomized complete block design with three replicates. Study materials were AVTO1429, AVTO1424, AVTO1314 from World Vegetable Center, four commercial varieties namely; Riogrande, Cal J, Roma VF, UC82 and three farmer selections namely; Valoria, Danny and Eden select. Genotype effects, genotype x environment interactions and location effects for days to flowering, plant height, maturity, fruit yield and related traits were highly significant (P<0.01). Duration of flowering varied from 36 to 42 days; plant height from 66.37 to 182.57cm, duration to maturity from 85 to 100 days, and fruit yield from 18.3 to 55.7 t ha-1. All the genotypes showed a determinate growth habit except AVTO1314 which had indeterminate growth habit. Genotype AVTO1429, AVTO1424 and AVTO1314 had green stem while commercial varieties and farmers’ selection had purple stem. The high genetic variation observed among the test genotypes for the traits evaluated can be exploited in developing the tomato breeding program. Key words: Tomato, accessions, characterization, flowering, morphological traits, agronomic traits.