Prerequisites and theoretical foundations of buckwheat breeding for intermediate cropping

Abstract

The paper presents the results of long-term researchon breeding buckwheat for intermediate crops. The aimof the study was to evaluate breeding material based on the relationships between agro-biological traits undervarious abiotic environmental conditions. The researchwas conducted in aftermath sowings in the south-westernForest-Steppe under the full selection scheme, and instubble crops in the southern Steppe at the levels of thecontrol nursery and competitive variety trials. The resultsdemonstrated the effectiveness of individual selection ofbuckwheat based on the biometric trait “stem branchingzone” (SBZ) and its influence on the duration of the vegetationperiod. Correlation relationships were establishedbetween the productivity of the breeding material and theintegral SBZ value, as well as the quantitative compositionof the population structure of biotypes distinguishedby this trait. Under the conditions of the south-westernForest-Steppe, the correlation coefficients ranged fromr = 0.701 ± 0.12 to 0.761 ± 0.12, while in the southernSteppe they were r = 0.723 ± 0.1 to 0.775 ± 0.09. A correlationrelationship was also identified between the SBZvalue and the vegetation period duration of the breedinglines. Under aftermath cropping conditions, the correlationcoefficients were: r = 0.968 ± 0.069; 0.989 ± 0.040;0.991 ± 0.037. In stubble cropping conditions, the valueswere r = 0.898 ± 0.127; 0.861 ± 0.146; 0.764 ± 0.185.Another correlation was observed between the nectarproductivity of buckwheat plants during mass flowering inaftermath crops and the vegetation period duration of thebreeding lines. Depending on the year of study, the correlationcoefficients were: r = 0.861 ± 0.09; 0.697 ± 0.14;0.712 ± 0.11. The obtained results indicate that whengrown as an intermediate crop in the south-western Forest-Steppe, buckwheat grains accumulate more protein comparedto grain produced in stubble cropping conditions inthe southern Steppe. Protein content ranged from 15.05 %to 16.2 % in the Forest-Steppe and from 13.3 % to 15.3 %in the Steppe zone.