Avaliação das características morfofisiológicas e da produtividade de soja (Glycine max (L.) Merrill) em função de diferentes níveis de vigor de sementes

Abstract

Vigor is na inherent characteristic of the seed and is independent of germination, so a seed can have a high germinative potential and have a low vigor. Vigor plays na important role in seedling development when in na adverse climate condition in the field. In view of this, the work aimed to evaluate the difference in productivity and morphophysiological characteristics of soybean plants (Glycine max (L.) Merrill), according to seed bacthes containing different levels of vigor. The experiment was conducted in the city of Maringá-PR, with the variety Monsoy 6410 IPRO, and all batches with germination percentage above 80%, sown in na area of 825 m². The treatments were divided according to the seed vigor by the accelerated aging test, being T1, T2, T3, T4 and T5 with vigor values of 90%, 71%, 74%, 58% and 76%, respectively. The variables evaluated were: Seedling count emerged in the field, germination index (IVG), plant height, dry matter, number of nodes per plant, weight of a thousand grains, grain moisture and grain yield in kg.ha ⁻¹. The results made it possible to verify that medium to high vigor seed batches are able to emerge uniformly and more quickly than low vigor seed batches, that is, treatments 1 and 5 higher IVG indexes, 1.93 and 1.86, respectively, if compared to the batch with less vigor, with 1.28. This may be na indication that seeds of medium to high vigor conditioned to different stress conditions at the beginning of their development, would support better this conditions, if compared to low vigor. Productivity may not be a characteristic directly affected by vigor when adjusting a plant population, taking into account the germination test.