SEED KERNEL TO SEEDCOAT RATIO AS AN INDICATOR OF EFFICIENCY OF LINSEED GROWING
For many years sunflower has been a leading oilseed crop in Ukraine. However, this crop depletes the soil, which leads to irreversible consequences. Linseed can be an alternative to sunflower. It is a valuable oilseed, which is a good predecessor for many crops. Such biological characteristics as a short growing season and drought tolerance make this crop suitable for cultivation in Ukraine, especially in the south and east. Today, at the Register of Plant Varieties suitable for cultivation in Ukraine nearly two dozen varieties of linseed from various agencies are presented. But only one of them - Svitlozir, created at the Institute of Oilseed Crops of NAAS has big seeds. Weight of 1,000 seeds of this variety is more than 9 g, whereas for all other varieties this index varies around 6-8 g. It is known that the most of oil in the seeds of oilseed plants, including linseed, is in the seed kernel but not in the seedcoat. Therefore, the ratio of seed kernel to seedcoat weight will significantly affect the production output, that is oil, for which oilseeds are grown. The aim of our research was to determine the weight ratio of seed kernel and seedcoat in small-seeded and large-seeded varieties of linseed to determine the profitability of their cultivation. As the material for research small-seeded (Solnechniy and Kivika) and big-seeded (Svitlozir) varieties of linseed with a mass of 1000 seeds of 5.2 g, 5.8 g and 9.2 g, respectively, were used. Solnechniy is the variety of Belarusian breeding while Kivika and Svitlozir varieties were created at the Institute of Oilseed Crops of NAAS. The seeds of each variety, 50 pcs. in triplicate, were manually separated on a kernel and coat parts, weighed and compared. The data were treated statistically. Despite the fact that between the weight of the seed kernel and seedcoat were significant differences in all studied genotypes, in small-seeded Solnechniy and Kivika varieties the proportion of the coat is almost the same as the proportion of the kernel. At the same time, the proportion of kernel in big-seeded Svitlozir variety was almost twice more than that of the coat. Thus, in small-seeded varieties the kernel to coat ratio is about 1.2 : 1, while in the big-seeded - 1.9 : 1. Oil content in the seeds of Solnechniy and Kivika does not exceed 42% and 44%, while the oil content in seeds of Svitlozir is 50%. If we assume that the studied varieties are characterized by the same ratio of kernel and coat at the level of large-seeded variety, the calculations show that at the yield of 18 centners per hectare when growing Svitlozir variety we can get 585 kg of oil per hectare, while Solnechniy and Kivika varieties - only 491.4 kg and 514.8 kg, respectively. If we take into account that the oil in the seeds of oilseed crops mostly stores in their kernels, but not in the seed coat, even at equally high, such as at 50% oil content of all three varieties, the oil output depending on the kernel to coat ratio will also be different. In Svitlozir variety it will be 585 kg per hectare, and Solnechniy and Kivika varieties - respectively 495 kg and 486 kg. So, we can say that the cultivation of highly big-seeded linseed varieties is more cost-effective than the cultivation of small-seeded ones. Thus, the oil yield per unit area does not depend only on the oil content in the seeds of a linseed variety, but the ratio of kernel to coat as well. With the increase of the kernel proportion, that is directly related to seed size, oil collection will be considerably larger.