Inheritance of sunflower (Hellianthus annuus L.) seed size in the cross combination L12B х KP11B

Abstract

One of the main parameters in sunflower breeding is the size of seeds. Usually in breeding selections for this purpose is used an indicator of weight of 1000 seeds. It is necessary to know type of inheritance of the size of seeds expressed both in weight of 1000 seeds and in their sizes for selection of parental components at heterosis selection. At the same time, the genetics of these features have been studied much less than other economic features. The aim of the study was to determine the type of inheritance in the first and second generation of signs of weight of 1000 seeds and seed length in combination with crossing lines with conventional round and large long seeds. Comparison of parent lines by weight of 1000 seeds using student's test indicates a significant difference. The second generation offspring were divided into 16 classes. The plants of the first and second generation along with the parent lines were distributed by weight of 1000 seeds. There were measured 68 plants of L12B, 160 plants of KP11B, 25 hybrid plants of the first generation, two progeny of the hybrids of the second generation of 70 and 57 plants. The smallest weight of 1000 seeds of the KP11B line was 85 g, and L12B had the largest 65 g. We assumed three possible ratios of cleavages for digenic control of the trait: 9:6:1, 12:3:1, 15:1. The digenic model was chosen because of the small number of plants of the second generation corresponding to one of the parents. According to the obtained Pearson criteria on the basis of the weight of 1000 seeds, the hypothesis of the digenic recessive control of a smaller weight of 1000 seeds can be unambiguously confirmed – the ratio of 15:1. In our populations of the second generation high correlation coefficients between the signs of weight of 1000 seeds and length of seeds were revealed: 0.66 and 0.68. On the basis of the length of the seeds, the same measurement of each plant of parent lines and hybrids was carried out. The model of splitting 15:1 was reliable for both offspring and their sum when referring to a smaller part of plants with a small seed length, as in the L12B line. Also reliable in all variants was the ratio of 9:6:1 – with the release of the plant class of the second parent line KP11B. It shows differences about control of the length of the achenes of lines KP11B and L12B. Dominant alleles cause a greater length of the achenes. Genes have complementary interactions.