The assessment of zucchini tolerance to unfavorable factors is based on the calculation of mathematical indices, such as the Stress Susceptibility Index (SSI), Stress Tolerance Index (STI), Tolerance Index (TOL), and Geometric Mean Productivity (GMP). High STI and GMP values, combined with minimal SSI and TOL values, indicate the genotype's ability to maintain yields under conditions of moisture deficit or temperature fluctuations.
At the physiological and biochemical level, tolerance is determined by the plant's ability to maintain low levels of lipid peroxidation, measured by malondialdehyde (MDA) content, and high antioxidant activity. Selection also considers morphometric indicators, such as root and stem biomass accumulation dynamics, as well as visual scoring scales for assessing the severity of infectious diseases.
Tolerance in zucchini crops directly determines the stability of marketable fruit yield under stressful weather conditions and their ability to withstand storage without low-temperature damage. Selecting tolerant genotypes allows for increased resource efficiency in cultivation through more rational use of water and nutrients under limiting environmental conditions.
General information about the subject — on the page
Tolerance.