producing hybrid lettuce is prevented by flower structure and usually lead to selfing. based on it, this experiment was carried out to evaluate the performance of different physical and chemical emasculation methods for producing lettuce hybrid seed. a numbers of cultivars with dominant and recessive traits were used as male and female parents, respectively. in the first experiment, physical em...

Purpose: The primary objective of any breeding program is to increase yields, thus superior lines based on yields are used as parents. After parents’ selection, hybrids may not perform expected because the performance influenced by interactions genotypes used, which breeder must be well conversant with for accurate prediction ultimate hybrids. 
 Methodology: This study aimed at characteriz...

inheritance of several yield-based drought resistance indices was studied by a halfdiallel method using seven winter wheat varieties. the parental lines were such chosen as to represent a broad range of drought stress resistance. the experiment was conducted in a split-plot design at the research farm, faculty of agriculture, zanjan university, iran, in 1998. irrigated vs. rainfed regimes w...

In order to understand the molecular basis of chicken heterosis in reproduction traits, mRNA differential display (DDRT-PCR) methods were used to analyze the differential gene expression of ovary tissue between hybrids and their parental lines in a 4×4 diallel cross, involving 4 chicken breeds, which were White Plymouth Rock (E), CAU Brown (D), Silkies (C) and White Leghorn (A). Total of 331 di...

The inheritance of stress responsiveness (line effects and combining abilities) was phenotypically studied in progeny from diallel crosses of randombred (RB) quail and quail selected for exaggerated (high stress, HS) or reduced (low stress, LS) plasma corticosterone (CS) response to brief immobilization. The three genotypes were crossed in a 3 x 3 factorial arrangement of treatments that allowe...

Crop seeds are important sources of protein, oil, and carbohydrates for food, animal feeds, and industrial products. Recently, much attention has been paid to quality and functional properties of crop seeds. However, seed traits possess some distinct genetic characteristics in comparison with plant traits, which increase the difficulty of genetically improving these traits. In this study, diall...

Global efforts are underway to biofortify cassava (Manihot esculenta Crantz) with provitamin A carotenoids to help combat dietary vitamin A deficiency afflicting the health of more than 500 million resource-poor people in Sub-Saharan Africa. To further the biofortification initiative in Uganda, a 6×6 diallel analysis was conducted to estimate combining ability of six provitamin A clones and gen...

Using native trees from near the northern and southern extremities of the relatively continuous eastern distribution of Eucalyptus globulus in Tasmania, we compared the progenies derived from natural open-pollination (OP) with those generated from within-region and long-distance outcrossing. Controlled outcrossing amongst eight parents - with four parents from each of the northern and southern ...