Evaluation of the combination ability of parental watermelon lines for their use in hybrid breeding
The increase in the volume of commercial production of watermelon along the northern border of melon growing (Saratov, Voronezh, Kursk regions, the Altai and Primorye Territories, etc.) requires the creation of ultra early and early varieties and hybrids. They should have a number of economically valuable signs, high transportability and resistance to disease. It is preferable to create heterotic F1 hybrids, which allow obtaining guaranteed yields of fruits. To obtain such hybrids, it is important to have a maternal form that has genetic male sterility and allows to obtain seed hybridity up to 90% and higher. Watermelon has a maternal line with genetic male sterility, controlled by the gene - ms, which has two genetic recessive markers: dissected leaf plate (l), light color of the fetus (q). The acquisition of promising hybrids F1 depends on the correct selection of parental pairs, giving a heterotic effect due to their high combinational ability. Inbred paternal lines for the early and middle group of varieties were created for phenotypic homogeneity. Determination of the overall combinative ability for precocity and yield will allow to establish the most effective hybrid combinations with a high heterotic effect. The vegetation period in F1 hybrids is inherited intermittently. In terms of productivity, in the early group of varieties, the hybrids of the Lhms x Success, Lchms x Delight, were exceeded, exceeding the standard by 12.0 - 38.0 c / ha, in the middle group of Lchms х Favorit - 13.0 c / ha. The effect of the ACS on yields varied from 22.7 to 61.6 centner / ha in 2015, from 32.9 to 42.4 centner / ha in 2016. According to the productivity and the length of the growing season, three father's lines of watermelon were singled out: Success, Favorite and Icarus. A promising heterotic hybrid F1 Watermelon Temp (Lhms x Success) was transferred to the State Variety Test. An analysis of the ACS of the mother lines showed that the Chms-3 line emerged from the three studied lines from the mean effects of ACS for precocity, and for the yields of LCs-1 and LC-2.