Study And Identification Of Highly Resistant Hybrides To Verticillium Dahliae, By The Enzyme Peroxidase

Abstract

Peroxidase is the main enzyme of the phytoimmunity of cotton, which plays a great practical role in breeding new varieties of cotton. 29 samples of cotton were extracted by CBSPARI researchers and transferred for appropriate biochemical analysis to the Institute of Bioorganic Chemistry of the Academy of Science of Republic of Uzbekistan. In the experiment, the optimal conditions for the determination of peroxidase activity were determined, then its activity was revealed in seedlings of cotton seeds, and responsiveness to the most important stresses was established. In the field, the most stable families were the complex interlinear hybrids F₄: F₄[F₄(L-101 × L-108) × L-102], F₄[F₄(L-105 × L-106) × L-106], F₄[ F₄ (L-105 x L-106) × L-105]. As a result of the studies, seeds of 29 different cotton samples were tested to study the activity of the enzyme chitin-specific peroxidase. For this purpose, wild-growing seedlings of species and families of hybrid cotton combinations used in the developing of a new variety have been used to select a selection material of high resistance to Verticillium dahliae Klebhan. In the work on evaluation for verticillium wilt  biochemical tests using marker enzymes of phytoimmunity – “chitin specific” peroxidase were used. As a result of a biochemical study in laboratory conditions, it was established that, to the resistant pathogen V.dahliae, among the samples studied, one should include: the wild type of cotton G.laxum and the complex interlinear combination F₆[F₄(L-105 x L-108) x L- 104]. The family isolated from the F₆ hybrid [F₄ (L-105 × L-106) × L-106] was used as origin family in breeding a new cotton variety C-6577, which was transferred for examination to the State Test from 2018.