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The genetic variability of important fiber quality traits of cotton such as: uniformity Index (UI); fiber elongation before breaking (Elongation, Elg) and micronaire (Mic) were studied. Qualitative characteristics were tested on the HVI (High Volume Instrument) system, in accordance with the international classification. Local cotton varieties (Agdash-3, AP-317 and Elekberi), Turkish testers (Sezener 76, Naz 07, Ozbek and GSN 12) and 12 incomplete diallelic hybrid combinations were evaluated to determine the potential of parental varieties, F1 and F2 hybrids using effective method - combining ability. Analysis of variance, carried out on the basis of data from all studied combinations, made it possible to identify one local line (AP-317) and two foreign testers (Naz 07 and GSN 12), which had, to varying degrees, positive effects of total combining ability (TCA). This indicates additive types of expression of non-allelic genes responsible for the formation of the studied qualitative properties of cotton fiber. Variations in the SCS of hybrid combinations were generally lower than the effects of the GCS. When assessing second-generation hybrids, we determined that lines and testers with positive effects of GCA and hybrid combinations with their participation were distinguished by high indicators of the fiber quality in the next generation. Consequently, selection of genotypes with improved fiber quality carried out in early generations can be effective, which will accelerate the creation of new promising varieties and lines of cotton. [ABSTRACT FROM AUTHOR]

Cotton growing, being an important agro-industrial object, is being improved through the introduction of new mechanisms to increase resistance to various external stress factors. Taking into account the previously studied phytohormones, the purpose of our study was to identify the effect of the salicylic acid derivative, dinitrosalicylic acid (DNSA), on the biochemical processes in the common cotton AP-317 genotype. It was established that low concentrations of DNSA-0.01 mM decreased production of NO radical, catalase and PPO activity, as well as absorption of phosphorus-anions from the nutrient medium, while higher doses of them has led to the stimulation of NO radical production, increased peroxidase activity, stabilized absorption of phosphorus anions. It was also found that at low concentrations of DNSA took place slightly activation of SOD activity, but not at relatively high concentration of DNSA. Electron paramagnetic resonance analysis of the root and leaf tissue of the plant showed an increase in the concentration of magnesium and iron ions when exposed to DNSA. It was also found that DNSA increased the concentration of lipid peroxide radicals at 0.1 mM in both tissues. [ABSTRACT FROM AUTHOR]

The effect of a highly virulent fungus Verticillium dahliae Kleb. VD-11, with non-defoliating strain on polyphenol oxidase (PPO) and the antioxidant enzymes, such as guaiacol peroxidase (POX) and superoxide dismutase (SOD), was studied in double haploid cotton variety-Pima 3-79 (Gossypium barbadense L.), highly inbred line TM-1- (Gossypium hirsutum L.), as well as in genotypes CS B-15 and GS B-22, created by the substitution of one chromosome of TM-1 with the chromosome 15 and 22 of Pima 3-79 respectively. The treatment of plants with the pathogen led to an increase in the activity of PPO approximately 1.2 times in the case of TM-1 and CS B-15. However, these changes were insignificant in the case of Pima 3-79 variety, whereas the activity of the enzyme in the case of CS B-22 was decreased apparently. Similar effects were also obtained for POX. After inoculation, the activity of SOD in all genotypes, except CS B-15, was increased. On the contrary, the activity of SOD was decreased in the case of CS B-15 genotype. It was found that plant infection with the pathogen leads to a change in the concentration of free radicals, which, in turn, affects the activity of antioxidant enzymes. The fungal infection also led to the creation of new paramagnetic centers and nanophase crystal-like iron oxide particles in roots, but not in leaves. [ABSTRACT FROM AUTHOR]

The main objective of our research was to determine the effect of various concentrations of IBA on the activity of numerous prooxidant-antioxidant enzymes, NO content and on the components of the photosynthetic apparatus: chlorophyll a, b and carotenoids in cotton seedlings of Gossypium hirsutum Agdash-3 and Gossypium hirsutum AP-317 genotypes. Our study also focused on the impact of different concentrations of IBA on the dynamics of the activity of polyphenol oxidase, which plays an essential role not only in the metabolism of phenolic compounds but also in the involving of these compounds in the defense response of plants. The results indicate that IBA participated in modulating the activity of prooxidant-antioxidant enzymes (CAT, POX, SOD, and PPO), the formation of the NO and components of the photosynthetic apparatus. At the same time, the activity of SOD and catalase changed insignificantly, which may indicate lower effect of IBA on these two enzymes [ABSTRACT FROM AUTHOR]

In this study, the non-linear stability of three-layered conical shells with functionally graded core have not been investigated previously. The purpose of this paper is to study this problem. The large deflection theory with von Karman-Donnell-type of kinematic non-linearity is used to deduce the basic equations. The basic equations are solved analytically by using superposition and Galerkin methods. The influences of several parameters on the dimensionless non-linear critical axial loads are discussed. [ABSTRACT FROM AUTHOR]