THE DECLINE IN VIABILITY AND VIGOUR OF THE HYBRID MAIZE (ZEA MAYS L.) SEED UNDER THE INFLUENCE OF GENOTYPE, DURATION AND THE FACTORS OF THE STORAGE ECOSYSTEM

Abstract

The objective of this research was to determine the changes in quality of maize (Zea mays L.) seed over the three years storage and in five genetically different hybrids, in during storage, under open storage conditions. Also the aim of this study was to evaluate the effect of different type treatment on physiological potential maize (Zea mays L.) seeds. Five experimental corn hybrids, each represented by five seed lots produced by Agricultural Research and Development Station Turda, Romania, were evaluated. Seeds were stored for 36 months, under different environments and seed performance was evaluated the time of “initial-phase” and every 12 months by seed viability (germination), seed vigour (seedlings length, İndex Vigour-I - SVI), Speed Germination Index (SGI). The results indicate that the contribution of the factors taken into consideration, at the total variability of viability (germinations) is: hybrid, 26.01%; storage conditions (treatment), 9.99%; storage duration, 31.75%, and in case of seed’s vigor variability (İndex Vigour-I) is: hybrid, 5.5%; treatment, 25.20%; storage duration, 46.69%. The study’s purpose was to identify which of the studied genotypes preserves better its initial seminal qualities during storage duration. The large variation range of regression coefficient bi[0.30 - 1.684] and of determination coefficient Ri 2 [0.68 - 0.90], residual deviations δij² and of ecovalence coefficient Wi 2, indicates the fact that there are differences regarding the behaviour of genotypes in analyzed environments which means differente reactions of hybrids taken into consideration, targeted by the storage conditions and storage duration. A model was developed for viability equations to quantify the effect of storage conditions to „open space” on the orthodox seeds (Zea mays L.) deterioration.