Early-early maturing soybean cultivars for the northern-western zone of Russia

In 2006-2010, 35 early-early maturing soybean cultivars and lines of different origins passed through a comparative testing in conditions of Vologda region. It allowed selecting the most reliable and stable cultivars on maturing in this condition. The productive abilities of the best cultivars were tested in trials of the last four years (2011-2014). The trial showed that the cultivar SibNIIK-315 exceeded the other studied cultivars Kasatka, Svetlaya and Eldorado on seed yield and protein content in seeds. These four cultivars passed through a comparative trial (in small plots in field) in conditions of Vologda region (the Northern base station) in 2011-2014. The research proved a significant (on 37%) advantage of the cultivar SibNIIK-315 on seeds productivity compared to the cultivars Svetlaya and Rasatka of the Ryazan NIPTI APK breeding. This cultivar is characterized with the highest protein content in seeds - 41.2%, that is 0.5-0.8% higher compared to the other studied cultivars. The natural hydrothermal resources of the southern-western zone of Vologda region (the sum of active (> 10 °С) temperatures is 1700-1800 °С and precipitations are 250-350 mm for a warm period of May-September) allowed to form a biological seed productivity up to 450 g/m 2 at the cultivar SibNIIK-315 and up to 400 g/m 2 at the cultivars Svetlaya and Eldorado, and up to 350 g/m 2 at the most early-early maturing cultivar Kasatka. This data certifies the real possibility to introduce such soybean cultivars into the northern-western zone of the European part of the Russian Federation up to 60° NL.