Improving Sesame (Sesamum indicum L.) Seed Yield through Selection under Infection of Fusarium oxysporum f. sp. sesami

Abstract

Sesame (Sesamum indicum L.), the Queen of oilseeds, is infected with different pathogens, restricting its yield. Fusarium oxysporum f. sp. sesami is the most destructive disease of sesame worldwide, causing economic losses. This work aimed to develop new high-yielding strains, resistant and/or tolerant to Fusarium. Two cycles of pedigree selection were achieved under infection of Fusarium oxysporum f. sp. sesami. Two populations in the F2 (600 plants each) were used. The selection criteria were five single traits and another three restricted by yield. The restricted selection was better in preserving variability than the single trait selection. The observed genetic gain in percentage from the mid-parent in the F4-generation was significant for the eight selection criteria. Single trait selection proved to be an effective method for improving the selection criterion, but it caused deleterious effects on the other correlated traits in most cases. The seed yield increased by 30.67% and 20.31% from the better parent in the first and second populations, respectively. The infection% was significantly reduced by 24.04% in the first, and 9.3% in the second, population. The selection index improved seed yield, and its attributes can be recommended.

Estimation of Genetic Parameters and Path Analysis of Sesame Genotypes under Three Plant Distributions

“…We note from Table (1) that genetic, environmental, phenotypic variances and studied traits differed from zero for the studied traits, and this means importance of estimating these variations on one correct and on other , genetic variation values were higher than environmental and studied traits, and this is evidence of greater role in inheritance of these traits It is due to the genetic variation in comparison with environmental variation and thus represented the largest value of phenotypic variation for these traits, and these results were consistent with [3]. Coefficient of genetic variation was mean for traits of seeds1000 weight and single plant yield and low for traits and plant height , leaf area per plant, number of capsules per plant and the number of its seeds coefficients of genetic and phenotypic variation give evidence of high heritability, and their height indicates the largest variances among plant populations [5]. The results of the same table show that the values of degree of heritability in broad sense were high in first environment and for traits studied, and this indicates a greater participation of genetic variation compared to environmental variation In inheritance of these traits and can be improved genetically (management of genetic variation) and obtained similar results [6] and that the values of genetic advance as mean were average for traits of plant height, the number of capsules per plant, seeds wei 1000 seeds, and single plant and the high values of expected genetic advance give an indication of possibility exercise of direct election and these results are consistent with [8].…”

“…Values of the coefficients of genetic, environmental and phenotypic variation ranged between low and high were obtained from [5] and that values of the degree of heritability are in the broad sense It was high and for studied traits it was medium, which is evidence of the contribution of genetic and epidemiological variation E in apparent variance and gives evidence of possibility of improvement by managing genetic and environmental variance, and this result agreed with [6] and that the expected genetic advance values as a mean were high for two traits of weight of a thousand seeds and single plant yield and reason is due to the high values of heritability in broad sense of these traits and high values for improvement, it gives an indication of the exercise of direct selection and obtained values that ranged between low and high for the expected genetic advance as mean [8].…”

“…Indirect and indirect, and the total effect of a non-independent trait on those independent traits [2], in an experiment applied to six genotypes of sesame, the environmental variance was higher than genetic for the two traits of number of capsules per plant seeds 1000 weight, while genetic variance was greater than environmental for trait of plant height [3]in their study of eleven sesame genotypes, concluded that genetic variation was more important than environmental variation for traits of plant height, number of capsules per plant, number of seeds per capsule, seeds 1000 weight and yield of single plant yueld [4] explained in a field experiment in which 33 were used. genotype of sesame showed that the coefficient of genetic and phenotypic variation was average for traits of plant height, number of capsules per plant, number of seeds per capsule, and seeds thousand weight and high for the single plant yield trait, [5] noted in a study that included several sesame genotypes that coefficient of genetic and phenotypic variation was low for plant heigh ttrait, [6] confirmed that the plant height trait and number of seeds per capsule were low in which degree of briad sense heritability in and high for trait of number of capsules per plant, [7] when they estimated the degree of broad sense heritability in that it was low for trait of number of seeds per capsule and high for trait of number of capsules per plant, it was found [8] that values of expected genetic advance as mean were low for two trait of plant height and single plant yield [9] the trait of number of capsules per plant, number of seeds per capsule, and seeds1000 weight of had a direct positive effect on single plant yield. This study aims at estimating the genetic parameters of traits under study, as well as analyzing the pathway by identifying most important traits in their direct impact on single plant yield and adopting them as electoral guides for distinct genotypes.…”