SEED QUA LITY INDICATORS OF WINTER BREAD WHEAT ACCESSIONS DEPENDING ON THE GRAIN SIZE

Scientific/theoretical review of studies of the seed size effect on the seed yield and sowing qualities was conducted. The results of a 2016–2018 study of the grain size influence on the germination energy, laboratory germinability and 1000-grain weight in winter bread wheat are presented. The relationship between the grain size and the sowing qualities of seeds was established. Varieties with a high 1000-grain weight (Doskonala, Pryvablyva, Smuhlianka, and Haiok) and high germination energy and germinability (Yednist, Harmonika and Bunchuk), as well as varieties and lines that showed a high germinability of small seeds (2.2 x 20 mm), were distinguished.

I.A. Lutak and A.V. Shapoval claim that the sowing qualities of the grown seeds do not significantly depend on the size of the sown seeds, and the highest yield of spring wheat seeds is achieved when seeds of 2.2 x 20 mm or larger are sown [13].
Purpose. To evaluate the influence of seed sorting by size on their quality indicators: germination energy, laboratory germinability and 1000-grain weight.
Material and methods. The study was conducted at the Plant Production Institute named after V.Ya. Yuriev of NAAS in 2016-2018. The technology of growing winter wheat (tillage, sowing time, sowing depth, etc.) is conventional for the eastern Forest-Steppe of Ukraine. The predecessor was black fallow. Sowing was performed by the standard method in four replications. The record area was 10 m 2 . Twenty six varieties and lines of winter bread wheat were studied.
Winter bread wheat seeds were separated on a laboratory separator RLU-3 by sifting through sieves with rectangular openings of 2.2 x 20, 2.5 x 20 and 2.8 x20 mm in accordance with the technique of qualification examination of plant varieties for suitability for dissemination in Ukraine [14]. The seed quality indicators were determined in accordance with DSTU 4138-2002 [15].
Results and discussion. 2017 had the best conditions for growing winter bread wheat seeds of good quality, and 2016 -the worst. Characterizing major grain sizes, first, one should determine the 1000-grain weight for each grain size (Table 1). Over the study years, the 1000-grain weight in winter wheat varieties (LSD BC 0.05 = 0.22) varied as follows: in 2016, the weight was 44.2-53.0 g for 2.8 x 20 mm seeds, 34.7-42.3 g for 2.5 x 20 mm seeds and 25.2-32.7 g for 2.2 x 20 mm seeds; in 2017, it was 44.5-54.6 g for 2.8 x 20 mm seeds, 36.1-43.8 g for 2.5 x 20 mm seeds and 26.3-33.5 g for 2.2 x 20 mm seeds; in 2018, it was 42.0-50.5 g for 2.8 x 20 mm seeds, 33.9-40.3 g for 2.5 x 20 mm seeds and 25.1-31.0 g for 2.2 x 20 mm seeds.
On average for the three study years, the following varieties were distinguished by the '1000-grain weight' trait: Doskonala (52.2 g) and Pryvablyva (51.3 g) for 2.8 x 20 mm seeds, Smuhlianka (42.1 g) and Doskonala (41.7 g) for 2.5 x 20 mm seeds and Smuhlianka (32.4 g) and Haiok (31.5 g) for 2.2 x 20 mm seeds. It should be noted that seeds of the same size had various weights of 1000 grains in different winter wheat varieties. It was also found that the significant difference in the 1000-grain weight was 9.9 g for seeds separated on sieves of 2.8 x 20 mm and 2.5 x 20 mm and 19.6 g for seeds separated on sieves of 2.8 x 20 mm and 2.2 x 20 mm. The effects of the factors 'variety', 'grain size', 'year' and their interaction on the 1000-grain weight were significant (P <0.05).
Yednist, Harmonika and Bunchuk had the highest average (across the three years) germination energy for all three grain sizes. The significant difference in the germination energy was 1.1% for seeds separated on sieves of 2.8 x 20 mm and 2.5 x 20 mm and 1.6% for seeds separated on sieves of 2.8 x 20 mm and 2.2 x 20 mm.
The effects of the factors 'variety', 'grain size', 'year' and the variety-year and grain sizeyear interactions on the germination energy and seed germinability were significant (P <0.05).
Conclusions. It was found that the grain size significantly affected the winter bread wheat seed quality: the larger seeds were, the higher the 1000-grain weight, germination energy and germinability were. In particular, the difference in the 000-grain weight was 9.9 g between 2.8 x 20 mm seeds and 2.5 x 20 mm seeds and 19.6 g between 2.8 x 20 mm seeds and 2.2 x 20 mm seeds; the difference in the germination energy was 1.1% and 1.6%, respectively; the difference in the germinability was 1.3% and 1.7%, respectively.
The weather in the study years significantly affected the germination energy, laboratory germinability and 1000-grain weight in winter wheat. Yednist, Harmonika and Bunchuk had the highest germination energy and seed germinability. In particular, their germination energy was 93.0-95.8%, and the germinability -93.3-96.3%.

Purpose and objectives.
To evaluate the effect of sorting seeds by size on their quality indicators: germination energy, laboratory germinability and 1000-grain weight. Materials and methods. The experiments were carried out in the experimental field of the Plant Production Institute named after V.Ya. Yuriev of NAAS in accordance with the field experimentation method in 2016-2018; 26 winter bread wheat lines and varieties were studied. The varieties and lines were grown in variety trial experiments; the plot area was 10 m 2 . Seeds were separated on sieves of a laboratory separator RLU-3; the 1000-grain weight was measured; the laboratory germinability and germination energy were determined. Results and discussion. When winter bread wheat seeds are sorted on sieves, they are separated into fractions with various 1000-grain weights. The separated fractions of winter wheat seeds have different sowing qualities. The 2.5 x 20 mm seeds and 2.8 x 20 mm seeds are of the best quality (germination energy, germinability). It was found that in 2016-2018, the germination energy, laboratory germinability and 1000-gain weight changed depending on the growing conditions. They were the highest in 2017. . To clean these varieties, especially in years with low seed yields, it is recommended to use seeds of the standard size (2.2-2.5 x 20 mm). Conclusions. The relationships between the grain size and sowing qualities of seeds have been established. Separation of seeds is an effective technological method allowing for selection of top-quality seeds.