LOAD OF BUSHES OF SEEDLESS GRAPE VARIETIES BY SHOOTS AND BUNCHES: A REVIEW

Abstract

The article considers the issue of loading bushes of seedless grape varieties with shoots and bunches in the world practice. The analysis is presented on the timing and length of pruning shoots, the load of bush by shoots, the load of bushes by bunches and methods for regulating the compactness of bunches of seedless grape varieties. The timing of pruning regulates the growth strength of shoots and the maturation time of early seedless grape varieties. Experiments on the timing of pruning often combined with subsequent treatment with growth regulators to increase yields. The length of the pruning of shoots affects the condition and death of the buds, the timing of the passage of phenological phases, productivity and quality of seedless varieties. Variety specificity and pruning dependence are noted: some varieties prefer short pruning (Perlett in India, White Seedless and Red Seedless in Iran), some – long (Beauty Seedless in India, Kishmish Batir in Uzbekistan, etc.). With an increase in the number of shoots per bush, yield capacity increase, however, the quality of grapes decreases, which also happens when the load of bunches increases. For the Jumba Seedless variety, despite the high performance with a low load of bushes with bunches, a higher one is recommended for an optimal ratio of productivity and quality. Thinning of bunches is also a common technique for regulating yield and quality, however, it is necessary to take into account the timing of thinning – too early removal of part of the inflorescences can lead to the formation of an excessively loose bunch, as in the BRS Vitoria variety in Brazil. Studies of the load of bushes of seedless grape varieties with shoots and bunches are relevant, especially in view of modern climate changes and increasing demand for high-quality products. Such studies are few in number in Russia, which requires closer study for the development of table seedless viticulture.