THE PHENOTYPIC FEATURES OF RED CLOVER (TRIFOLIUM PRATENSE L.) THAT CORRELATE WITH SEED PRODUCTIVITY

To reduce the time of the selection process when creating varieties of red clover (Trifolium pratense L.) with a high seed yield, it is necessary to use the source material with the features that positively correlate with an increased seed productivity. It is estimated that in the Northern part of the Central Black Earth Economic region of the Russian Federation the seed productivity of red clover has a high correlation with the weight of the dried mass, a number of stems, inflorescences, seeds in the flowers, seed setability, inflorescence dissemination and a short сorolla tube. The average correlation coefficient was found between the seed yield productivity (1000 seeds), the length of the stem and the full visibility of the leaf pattern. A lesser degree positive correlation was found between seed productivity and a number of beans in the flower, two-seeded beans, a number of internodes, the length of time from the beginning of the spring regrowth and up to the anrhesis. The research has revealed the correlations between the seed productivity and economic, biological, and morphological characteristics of red clover in the Northern part of the Black Earth Economic region of the Russian Federation, and the North Caucasus region, in particular in the Oryol Oblast and North Ossetia-Alania, where this crop occupies a leading position among the cultivated perennial herbs. It is used In biological farming at the hayfields and pastures. It was found that the seed productivity of the red clover as an individual plant is largely determined by the capacity of its development there was a high correlation between the seed yield and the dried mass of the plant (r = 0.72). The plants with the largest number of stems were characterized by the highest seed yield, which was inherent in both diploid and tetraploid cultivars (r = 0.61-0.79 and r = 0.55-0.83, respectively). The seed productivity of plants depended on the number of productive flowers on the plant (r = 0.57-0.78 for diploids and r = 0.76-0.89 for tetraploids) and their mass (r = 0.84). There is a lesser degree correlation between seed productivity and the number of beans in the flower (r = 0.12-0.18 for diploids and r = 0.04-0.16 for tetraploids). To a much greater extent, seed productivity depended on the number of seeds in the flowers (r = 0.79-0.81 for diploids and r = 0.63-0.86 for tetraploids). For the yield of tetraploid seeds, not only the total content of seeds in the flowers is important, but also the number of developed seeds (r = 0.84-0.89), since a significant part of the set seeds dies at various stages of ontogenesis and is removed during the sorting process. Seed productivity of red clover was largely determined by seed setability (r = 0.66-0.77 for diploids and r = 0.49-0.76 for tetraploids) and inflorescence dissemination (r = 0.71-0.80 for diploids and r = 0.70-0.75 for tetraploids). The seed productivity of red clover was associated with a mass of 1000 seeds. For diploid cultivars, this connection was mostly weak (r = 0.24-0.32), for tetraploids - average, which is due to larger seeds (r = 0.39-0.45). As for diploid cultivars, the presence of a weak correlation between seed productivity of the two-seeded beans (r = 0.09-0.18) and the number of stem internodes (r = 0.14) was found. The presence of an average correlation of the seed productivity with the full visibility of the leaf pattern (r = 0.30) was also noted.