Bacillus cereus Improves Performance of Brazilian Green Dwarf Coconut Palms Seedlings With Reduced Chemical Fertilization

Frontiers in Plant Science

Dalton Dias da Silva Júnior¹  Alessandra Jackeline Guedes de Moraes²  Ediane Conceição Alves²  Sidney D. Araújo da Costa²  Aline Figueiredo Cardoso²  Gisele Barata da Silva²  Paulo Manoel Pontes Lins³ 

[1] Federal University of Amazonas (UFAM), Education, Agriculture and Environment Institute, Humaitá, Brazil;Plant Protection Laboratory, Institute of Agrarian Sciences, Federal Rural University of Amazon (UFRA), Belém, Brazil;Sococo S.A Agroindústrias da Amazônia, Belém, Brazil;

关键词: Bacillus cereus;    coconut palm;    sustainable agriculture;    growth promotion;    PGPR;   

DOI  :  10.3389/fpls.2021.649487

来源: DOAJ

【 摘 要 】

Coconut production in the Amazon requires the knowledge and development of sustainable technologies to alleviate the detrimental effects of inorganic chemical fertilizers and intensive farming practices. In this study, we investigated the effects of plant growth-promoting rhizobacteria (PGPR) isolated from coconut seedlings on nutrient use efficiency (NUE) and physiological mechanisms related to biomass accumulation of seedlings grown with reduced inorganic fertilizer levels. Of the 96 PGPR isolates tested on rice plants, the isolate Bacillus cereus (UFRABC40) was selected, as it resulted in the most significant gain in growth variables. In a commercial coconut tree nursery, we subjected seedlings to two treatments, both with seven replications: control 100% NPK chemical fertilizer (CF) and B. cereus + 50% NPK CF. The results indicated that the inoculation increased phytohormone levels [190% indole acetic acid (IAA), 31% gibberellic acid GA3, and 17% gibberellic acid GA4] and leaf gas exchange [48% by assimilation of CO2 (A), 35% stomatal conductance to water vapor (gs), 33% transpiration, and 57% instantaneous carboxylation efficiency] in leaves. Furthermore, growth parameters (shoot, root, and total dry weight, height, and diameter) and macro- and micronutrient levels (95% N, 44% P, 92% K, 103 Ca, 46% Fe, 84% B) were improved. Our results show the potential ability of strain Bacillus cereus UFRABC40 to promote the growth performance of coconut seedlings under decreased application of inorganic fertilizers. The application of microbial-based products in coconut seedling production systems improves plants’ physiological performance and the efficiency of nutrient use.

【 授权许可】

Unknown