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Heat Tolerance and Adaptability to Drought in Sunflower Can Be Influenced by Pollen Selection

Abstract The heat tolerance and adaptability to drought of F2 sporophytic populations after F1 sunflower pollen heating have been studied. Freshly collected pollen was heated at the temperature of 60°C during 1 and 3 h and used to self-pollinate the emasculated F1 plants. Half of F2 seeds were treated with the temperature of 60°C during 15 min before sowing while another was not subjected to high temperature. The number of F2 flowering plants during 2013 dry summer season was counted. Pollen treatments compared with the control (fresh pollen) significantly increased the number of F2 plants after seed heating before sowing. In some F1 hybrids, pollen heating during 1 h was not effective. Pollination of F1 hybrids with pollen treated with the temperature of 60°C during 1 h compared with fresh pollen increased the number of F2 plants in dry field conditions. Obtained results show that pollen selection was successful to increase the heat tolerance and adaptability to drought in sunflower.