Genotypic variability in fruits characters of moroccan watermelon cultivars (Citrullus Lanatus) cultivars under well and limited watered conditions

Abstract

The aim of this study was to determine the effects of water stress on 9 watermelon genotypes among which five watermelon landraces collected in two localities (rasmouka and zagoura) and four commercial varieties F1. Two irrigation levels were imposed to determine variability on drought tolerance of cultivars. After the true leaves, irrigation treatments were initiated. T1 treatment received full irrigation based on depleted soil moisture in the root zone, T2 treatment received 50 % of T1.The drought tolerance was estimated by the ratio of the value of a trait under the T1 irrigation level and the value of this trait under the T2 irrigation level. For all the characters the mean values recorded in well irrigated conditions were greater than recorded in limited irrigated conditions. The analysis of variance revealed that genotypic differences were highly significant for all characters. Genotypes x trials interactions were also highly significant for all characters except TTS. Moderate to high values of broad-sense heritability were estimates for all characters measured except for fruit rind thickness. The values of heritability in limited watered where lower to those obtained in well‐watered conditions and the TSS had the highest value of heritability in well and limited watered conditions. The results show that the modern varieties are more susceptible to the hydric stress than the local landraces and suggest that genotypic variability for tolerance to drought stress exists among Moroccan watermelon cultivars and there is a need to screen a large number of genotypes to identifying and selection drought-tolerant genotypes.