Comparative Assessment of Winter Rye Varieties by Their Groat-Forming Ability

Abstract

The purpose of this research was to study the groat-forming ability of different varieties of winter rye and determine the specific varietal traits that positively influence the groat output. Fourteen varieties of winter rye differing in a number of morphobiological and technological grain properties served as the object of study. The varieties were grown on the fields of the Nemchinovka Research Center in 2015–2018. The weather conditions significantly varied during grain filling and maturing, which made it possible to assess their effect on the output of rye groats and their quality. The groat-forming ability was studied by peeling and grinding whole grains on a laboratory SATAKE gollender (Japan) without crushing. The output of whole kernel groats of three fractions (nos. 1, 2, and 3), as well as the output of crushed kernel and bran, were calculated. The summation of fraction nos. 1, 2, and 3 gave the total output of whole groats (%), which served as an index of the varieties' groat-forming ability. The final assessment of the studied varieties was given by comparing them with the standard variety, Valdai. The average output was 69.0% for whole kernel groats and 64.6–73.5% for the varieties. The output of the Valdai standard variety was significantly (by 4.6–7.1%) exceeded by five varieties: Alpha, Belozernaya 785, Moskovskaya 15, GK-494, and Zheltozernaya 760. Particular attention should be given to the Alpha variety, which clearly differed from the other varieties by a high falling number. It is shown that it is this property that determines the high output of whole kernel groats in this variety (73.5%). A high output of groats was also recorded for Belozernaya 785 and Zheltozernaya 760 varieties with a white and yellow grain color. The groats of these varieties are of the same color as wheat groats, which increases their consumer properties. The lowest total output of groats was recorded for GK-985 (64.6%), which is explained by a high output of crushed kernel (13.9%). The varieties with a high total output of groats had the lowest percent of crushed (beaten) kernel (5.6–6.9%), while their content was the highest for the varieties with a very low groat-forming ability (11.2–13.9). The grain peeling procedure considerably influenced the falling number and protein and starch content in output products. The falling number significantly increased, while the protein and starch content decreased for whole kernel groats. It is revealed that the total output of whole kernel groats significantly depended on the variety genotype (H2 = 0.94) and is relatively poorly modified by weather conditions. It is concluded that the groat-forming ability of rye is closely related to the strength characteristics of the kernel as well as to the resistance of the variety to lodging. A model of a rye variety with high groat-forming properties is given; prospects of breeding in this area are discussed.