Initial development of millet with use of biostimulant under different temperatures

Resumo

Millet is an important summer grass used as forage grass due to good bromatological characteristics and easy adaptation to Brazilian environmental conditions. However, when sowing the crop early in the southern region, situations may occur where low temperatures affect germination and seedling development. Thus, the present work had the objective of evaluating the germination and initial development of millet using Biozyme TF® biostimulant as a way to attenuate the effects of different temperatures. The experimental design was completely randomized, in a factorial scheme 3 x 5 (temperatures x doses) with four replicates each. The temperatures used were 15 °C, 20 °C and 25 °C and the doses used were: 0 (control); 0.25; 0.5; 0.75 and 1 ml kg^-1. After the treatment, the seeds were evaluated by: germination test, germination speed index, shoot and root length and seedling dry mass. The data obtained were submitted to analysis of variance with Sisvar® software and, when found significant, the regression analysis was performed. The germination of millet seeds is favored, under low temperature stress conditions, with seed treatment at the dose of 0.50 ml kg-¹ of biostimulant. The biostimulant does not influence millet germination speed index. Under low temperature thermal stress the biostimulant minimally increases the length and dry mass accumulation of millet seedlings and attenuates the negative effects on root growth. The accumulation of dry mass of the roots decreased with increasing dose of the biostimulant under thermal stress condition.