Promoção de crescimento de plantas de tomate mediada por Bacillus methylotrophic

Abstract

The use of microorganisms for agronomic purposes has been well studied because it is a great alternative to reduce or eliminate the use of agrochemicals. The use of Bacillus methylotrophicus as plant growth promoters characterizes an alternative measure in agriculture. The objective of the present work was to test cassava (Manihot esculenta L.) and Araruta (Maranta arundinacea L.) powder as formulations in B. methylotrophicus cells, used to promote tomato growth, and to test B. methylotrophicus in the production of indole-acetic acid. The experiment was conducted in a randomized block design, consisting of 10 treatments, four blocks with four replicates of 15 plants. Seeds of tomato cv. Santa Cruz were microbiolized with suspension of B. methylotrophicus by immersion of the seeds in the liquid suspensions and mixtures in the powder formulations in the proportion of 20 g / kg of seed. The seeds were sown and maintained for 30 days in 1000 L beakers of 7.9 cm higher diameter containing soil + autoclaved manure in the proportion 3: 1, leaving one plant per cup. The percentage of germination was evaluated at 14 days after sowing, characterized as the portion of germinated seeds presenting the first two leaves visible above the substrate. Growth parameters were also evaluated at 30 days of cultivation, including: plants, number of leaves, root length, stem diameter, root volume, dry mass and root and shoot strawberry, and IVP (plant vigor index). The microbiolization of the seeds for the propagation of B. methylotrophicus B47 and B12 iolates influenced the growth promotion and early stages of tomato plants, highlighting all the morpho-physiological attributes evaluated, stimulating greater growth in tomato plants. There was a significant effect of the formulations based on Cassava and Araruta containing the isolates B47 and B12: the treatments obtained a positive increase in the growth of the plants, being similar and superior in some respects to the commercial product Quartz®, and differing from the control treatments. The treatment containing B. methylotrophicus B47 presented significant values and superior to all the treatments in all attributes evaluated in pr. The treatments with the inoculation of the isolates B47 and B12 were the ones that presented the most promising results in the promotion of growth of tomato plants, increasing and accelerating the germination, obtaining a total accumulation of expressive biomass of these plants in a greenhouse. The in vitro suspensions and powder formulations of cassava and arrowroot containing B. methylotrophicus are efficient in promoting plant growth of tomato plants. The two isolates evaluated had a production above 18.20 a μg mL-1 of AIA, and the isolate B 47 presented values higher than those of isolates B12