Variation in the susceptibility of tomato (Lycopersicon solanum L.) genotypes to tomato yellow leaf curl virus (TYLCVD) infections at coastal savannah and forest zones of Ghana

Abstract

Little information is available on the resistance level of tomato genotypes to tomato yellow leaf curl virus disease (TYLCVD) and vector. Thirty-six genotypes representing the current available and accessible tomato germplasm in Ghana were evaluated in RCBD with three reps, under Coastal savannah condition at the University of Cape Coast (UCC). Five genotypes (K005, K100, K213, K116 and K042) selected for mild severity (ms); two genotypes (K027, K202) selected for severe symptom (SS) and one genotype (LC) selected for moderate severity (MoS) were re-evaluated under RCBD in three reps at UCC and forest condition at “Asuansi”. Genotypes K005, K100 and K213 were observed to maintain ms TYLCVD expression across locations but K116 and K042 had ms at UCC and MoS at Asuansi indicating respective stable and unstable host plant tolerance to TYLCVD across climatic zones. PCR test with two primer pairs for Asuansi samples revealed that PTYv787/PTYc1121 primer had amplified TYLCV DNA in all the eight genotypes. AV494/AC0148 primer had amplified TYLCV DNA in all the genotypes except in LV and K213, suggesting that TYLCVD expression in LV and K213 observed morphologically could come from different viral strains. The whitefly population was significantly affected by genotype by environment interaction indicating variation of whitefly population from location to location