Influence of spring vegetation recovery time and sowing dates on yield of winter wheat varieties of different types of development

Abstract

The article presents the results of researchand the nature of yield formation in winter wheat varieties of different types of development depending on the timeof resumption of spring vegetation and sowing dates.The material for the research was wheat varieties«typically» winter and alternative type, of differentgenetic and ecological origin. Results. It is proved that inorder to obtain stable grain yield in the southern steppeof Ukraine it is necessary to use new varieties of winterwheat for late sowing dates (October, November) Askania,Askania Berehynia, Pearl and alternative type Clarissa,Solomiya. Creation of high-yielding varieties of differenttypes of development with weak photoperiodic sensitivityand short stage of vernalization promotes active springregrowth of plants with shortened days, which in turnprovides good use of moisture and intensive yield formation.The resistance of winter wheat plants of different genotypesto the delay of spring vegetation recovery time depends onthe need for the duration of the vernalization stage, whichis controlled by the V2d genetic system and sensitivityto the photoperiod (Ppd genes). In addition, the signof resistance to delayed recovery of spring vegetation isprobably also significantly due to epigenetic inheritanceas a result of genotype interaction and a sharp change inthe time of recovery of spring vegetation. In recent years,there has been a clear change in climate, in the formof warming and uneven redistribution of precipitationduring the growing season of winter wheat, especiallythe lack of them when sowing in the optimal time. Suchconditions require the study and creation of both “typical”winter wheat varieties and varieties of alternative type(two-handed) for late sowing, as well as take into accountdeviations from climatic norms, and make adjustments tothe technology of growing winter wheat. Conclusion. Thetime of restoration of spring vegetation can both positivelyand negatively affect the yield of winter wheat, dependingon the state of development of crops (sowing dates)and genetic and biological characteristics of the variety.To realize the high yield potential, it is necessary tooptimize the varietal composition of wheat of differenttypes of development in response to different sowingdates for a particular region of cultivation. New varietiesof wheat of different types of development Askaniyskaya,Askaniyskaya Bereginya, Perlina and alternative typesClarissa, Solomiya form high yields at late sowing dates(20.10; 10.11) at the level of optimal term and above.