Genetic Resistance of<em> Solanum lycopersicum</em> L. (Tomato) to <em>Phytophthora infestans </em>and <em>Aspergillus niger</em>

There is limited information on genetic response of tomato cultivars to fungi. This study investigated genetic resistance of tomato accessions, chromosomes and morphological characters to Phytophtora infestans and Aspergillus niger infection. Thirty tomato seed accessions were grown in screen house using complete randomised design in triplicates, and evaluated for resistance to both fungi using disease severity rating scale of 1 (highly resistant) to 6 (highly susceptible), while chromosome assessment was done using Carnoys protocol. Morphological data of 28 characters were collected using IPGRI descriptor, while Variance components, Genetic Advance (GA) and Heritability were estimated for treated tomato and control using R statistical program. Accession NHT0254b that was highly resistant to P.infestans (1.00) and A.niger (1.33) were diploid (2n=2x=24). Phytophtora infestans treated NHT343a was moderately susceptible (3.67) with 2n=2x=23, while NGB00711 was moderately susceptible (4.33) with 2n=2x=22 after A.niger treatment, indicating aneuploidy. The Environmental variance (1509.57) and genotypic variance (8.22) were highest for Cumulative Fruit Weight (CFW) and Number of Seeds (NS), respectively for P.infestans treatment, while GA (2.97) and phenotypic variance (754.91) were higher for NS and CFW, respectively in A.niger treatment. Heritability estimate showed that fruit length (63.0%), size of core (65.0%), and number of chambers (60.0%) were resistant to P.infestans, while only fruit length (56.0%) was resistant to A.niger for yield characters. Therefore, accessions and characters that showed resistance to P.infestans and A.niger are recommended for selection and genetic improvement.