Experimental researches had been carried out during 2012–2016 in the crop rotation of Sumy National Agrarian University (SNAU) of the Ministry of Education and Science of Ukraine. Soils on the experimental field of SNAU – black soil typical deep, non-humusful medium-loam with high and medium provision with elements of mineral nutrition. The humus content about 3.9 %. The reaction of the soil solution is close to neutral (5.8).
The analysis of the weather conditions of 2012–2016 researches was conducted on the basis of annual data provided by the meteorological station of the Institute of Agriculture of the North-East of the NAAS, located five kilometers from the experimental field of SNAU. The SNAU soils are classified in the second agro-climatic region of the Sumy region, which according to a long-term data is characterized by temperate continental climate with warm summers and not very cold winters with thaws. Average daily (average annual) air temperature during 2012–2016 fluctuated from +7.9 to +9.5 ºС, and the legth of the frost-free period was close to 230 days. Long-term indicator, precipitation falls within 597–600 mm, with most of it – in the warm period (April-October). In general, the weather conditions during the winter wheat vegetation periods differed from the average annual parameters of the temperature regime, the amount of precipitation and their monthly distribution. It should be noted the excess of temperature to the average long-term index, as well as a slight precipitation increasing. In general, it facilitated to a comprehensive evaluation of the studied Chinese varieties as for an adaptive ability under condition of Ukraine.
The samples of Chinese winter wheat varieties which originated from the expeditionary gatherings conducted by V. A. Vlasenko in Gansu and Hebei provinces in (2000–2012) were the material for conducting researches. The cultivar Podolianka (the standard) was used in the study for comparison. The research was carried out using field, laboratory and mathematical-statistical methods. Phenological observations and records, evaluation and harvesting were conducted in accordance with generally accepted methods.
The results of research as for adaptive potential of Chinese bread winter wheat varieties are presented. 50 new cultivars of Chinese origin were analyzed under the conditions of left-bank side of North-East Forest-Steppe of Ukraine: super-early varieties – 10 %; early ripening varieties – 54 %; middle-early varieties – 12 %; mid-ripening varieties – 24 %. As for the level of tolerance for winter conditions, all groups of alien crops were inferior to the standard (cultivar Podolyanka) though they had a great level of index (6.4–7.9 points). In general, Chinese cultivars under the conditions of the research were characterized by relatively satisfactory tolerance for winter conditions; 52 % of analyzed patterns wintered at the level of standard with 8 points. Among them: super-early varieties – 2 %; early ripening varieties – 20 %; middle-early varieties – 8 %; mid-ripening varieties – 22 %. As for the height of the plants we identified – from medium-sized (81‒110 cm) forms to dwarf (30-50 cm). The analyzed genotypes divided into medium-sized forms – 22 %, dwarf forms – 14 % and semidwarf forms – 64 %. There was a direct relation between: a plant height → group of ripeness (r = 0.96) → group of ripeness (r = 0.92) → resistance to overwintering (r = 0.78). Among the analyzed patterns high resistance against a group of diseases had the varieties: middle-early genotypes – Longzhong 10, Zhong mai 19, Shijra zhuang 8; mid-ripening genotypes – Longzhong 1, Longzhong 3, Longzhong 2, Longzhong 4, Longzhong 12, Longzhong 7; early ripening genotypes – DF529, Lankao 906, DF581, СА0175, Zhongmai 9, Shi 4185, Jimai 22, Shixin 733, Shimai 12. As for the crop better than the standard: early ripening varieties –Jimai 19, DF529; middle-early varieties – Shijiazhuang 8, Longzhong 10, Jingdong 8; middle-early varieties – NSA 97-2082, Longzhong 2, Longzhong 4, Longzhong 7, Longzhong 5, Longzhong 8, Longzhong 12, Longzhong 11, Longzhong 3. 16 % of analyzed cultivars distinguished by the totality of researched characteristics – DF529, Shijiazhuang 8, Longzhong 3, Longzhong 10, Longzhong 4, Longzhong 7, Longzhong 12, Longzhong 2.
Canopy assimilation surface and yield of winter wheat varieties under atypical weather conditions