Analysis of pollen in sunflower lines of a breeding and genetic collection

We studied pollen productivity and its morphological heterogeneity in the lines of the breeding and genetic sunflower collection. The research was carried out at the V.S. Pustovoit All-Russian Research Institute of Oil Crops, Krasnodar, in 2022-2023. Collection lines VK934, VK1-klp, VK678, VK876, In Krupnyak, VK195, MVG-8, VK416, L2138, K1587, KG49 and RIL200 were used. To assess the quality of pollen, we used the parameter of morphological heterogeneity of pollen grains, i.e. the proportion of atypical grains. The pollen productivity was assessed by two parameters: pollen weight and the number of pollen grains. A Biolab TS-2000 LCD MS 20 microscope was used at a magnification of 40×. A line L2138 was characterized by a maximum weight of 1.17 mg/anther and a number of pollen grains of 45,239 pieces/anther. A line VK876 had the minimal values of these traits - 0.25 mg/anther and 16448 pcs/anther, respectively. A high positive correlation of r = 0.90 was noted between these traits. In 2022, the average diameter of pollen grains in 12 studied lines varied from 30 to 32 µm, with an average value of 31 µm. In 2023, the minimal diameter of pollen grains was lower than in 2022 and amounted to 27 µm, the maximum was at the level of 2022 - 32 µm with an average value of 30 µm. Over two years of research, a line KG49 showed significant morphological heterogeneity of pollen, which was expressed in a high proportion of defective pollen grains (58%). A line VK195 was characterized by low morphological heterogeneity with a proportion of defective pollen grains of 5%.