Adaptability of Different Sunflower Hybrids to the Conditions of Insufficient Moisturening

Abstract

Expansion of variety and sustainable production of quality oilseed crops both in the world on the whole and in Ukraine in particular, is actual. The main factors of this are: the urgent need for raw materials, changes in weather and climatic conditions, changes in the structure of phytocenoses, development and spread of specific diseases and pests, and adaptive ability of species and varieties, etc. This problem is especially crucial when cultivating crops under stressful conditions of the Southern Steppe of Ukraine. In the cultivation of sunflower varieties and hybrids of modern plant breeding, we observe a pronounced reaction to changes in agricultural meteorological conditions of their cultivation. Our research was carried out for three years (2017-2019) in the Southern Steppe region of Ukraine, which has low rainfall. The methods of the analysis were field and mathematicalstatistical methods. We evaluated the levels of environmental plasticity in 23 sunflower hybrids. We used the Eberhard and Russel method (the plasticity and stability analysis) to fully evaluate new hybrids with regard to their adaptability to growing conditions and investigate the appropriate rate of response of genotypes to the growing technology. We have found that under the conditions of the Dry Steppe zone of Ukraine sunflower embodies its genetic potential by 45%. Based on the experimental data, we conducted the regression analysis resulting in a linear regression model that indicates the dependence of sunflower yield on agricultural meteorological indicators. The hydrothermal coefficient in 2017 was 0.75. Despite this, the sunflower plants formed the highest yield that year due to the sufficient minimum relative humidity of the air during flowering (BBCH 61-65) was 54.7%. Creating genotype shave an average value of plasticity of the yield (ranging from 0.83 to 1.19), namely: EU Arcadia SU, EU Genesis, NS-X-496, EU Generalis SL, EU Loris KLP, SI Bacardi KLP, SI Arizona. Hybrids of different intensity levels, that are genetically and biologically diverse, can be cultivated efficiently in different agricultural ecological growing zones.