Studies on Genetic Variability, Heritability and Genetic Advance in Cucumber (Cucumis sativus L.) Cultivars Collected from China and Nigeria

Cucumber is an important vegetable crop but has received insufficient breeding attention. The objectives of this work were to assess the genetic variability among the collected cultivars and estimate heritability and genetic advance to enhance selection for genetic improvement of Cucumber. The experimental materials comprised four cultivars from Nigeria and four cultivars from China. The cultivars were evaluated using randomized complete block design (RCBD) with three replications. Analysis of variance showed that the cultivars differed significantly (Pless than0.01 %) in all twelve parameters measured. Agronomic characterization showed there was genetic variability for genetic improvement. Estimate of genetic parameters indicated slightly higher phenotypic to genotypic variance indicating an environmental effect on the agronomic performance of the cultivars. Estimate of coefficient of variation showed high genetic coefficient of variation in all the characters measured indicating exploitable variations among the cultivars. All the traits were highly heritable implying that these traits are genetically controlled. High heritability coupled with high genetic advance over mean (GAM) observed in eleven parameters implied that these traits were controlled by additive genetic effect and can be transferred to generations. Since additive genetic effect predominates, cucumber genetic improvement through recurrent selection was recommended.