Interaction between thidiazuron and Azospirillum brasilense on yield characteristics and productivity of rice

Abstract

In rice, the use of the bacterium Azospirillum brasilense has shown to be very useful for the crop, being able to increase the final productivity of the same or reduce the need for nitrogen in topdressing. It has recently been noted that there are other regulators that perform other functions, such as thidiazuron (TDZ), a cytokinin-like substance that has been shown to significantly increase upland rice productivity. Thus, the present work aimed to verify the effect of the interaction between the foliar application of A. brasilense and thidiazuron doses applied at the occasion of the tillering of the plants on the productive aspects and crop productivity. The experiment was carried out in the agricultural years of 2015/16 and 2016/17, at the UNESP Teaching, Research and Extension Farm belonging to the Engineering Faculty of Ilha Solteira -UNESP, located in the municipality of Selvíria, MS. The experimental design was a randomized complete block design with a 2 x 4 factorial scheme with four replicates. The treatments were the combination of the presence or absence of A. brasilense foliar application with doses of TDZ (0, 0.5, 1.0 and 1.5 g ha -1 ) applied to upland rice cultivar BRS Esmeralda. Based on the results obtained for plant height, number of panicles per square meter, total number of grains and fertility of spikelets, mass of 100 grains and grain yield, it was concluded that, in the two agricultural years observed, there were no interaction and individual effects of the foliar application of the bacteria, and of the TDZ doses used at the time of tillering in the BRS Esmeralda cultivar.Interação entre thidiazuron e Azospirillum brasilense nas características produtivas e produtividade do arroz RESUMO: No arroz, o uso da bactéria Azospirillum brasilense tem se mostrado de grande utilidade para a cultura, podendo incrementar a produtividade final da mesma ou ainda, reduzir a necessidade de nitrogênio em cobertura. Recentemente notou-se que há outros reguladores que desempenham outras funções, como o thidiazuron (TDZ), uma substância de efeito citocinínico que se mostrou capaz de aumentar significativamente a produtividade do arroz de terras altas. Desse modo, o presente trabalho objetivou verificar o efeito da interação entre a aplicação foliar de A. brasilense e de doses do thidiazuron aplicadas por ocasião do perfilhamento das plantas sobre os aspectos produtivos e produtividade da cultura. O experimento foi realizado nos anos agrícolas de 2015/16 e 2016/17, na Fazenda de Ensino, Pesquisa e Extensão pertencente à Faculdade de Engenharia de Ilha Solteira -UNESP, situada no município de Selvíria-MS. Utilizou-se o delineamento experimental de blocos ao acaso, com esquema fatorial 2 x 4 com quatro repetições, cujos tratamentos foram a combinação entre a presença ou ausência da aplicação foliar de A. brasilense com doses de TDZ (0; 0,5; 1,0 e 1,5 g ha -1 ) aplicadas no arroz de terras altas cultivar BRS Esmeralda. Com base nos resultados obtidos para altura de plantas, número de panículas por metro quadrado, n...

Effects of beneficial microorganisms on upland rice performance

“…Additionally, for instant carboxylation efficiency, EiC, the highest value was obtained with the BRM32114 + pool of T. asperellum mixture (0.08 (μmol m -2 s -1 ) (μmol mol -1 ) -1 ); however, there was no significant difference from that of the control treatment. The increase in enzymatic activity associated with photosynthesis, enhanced by biotic factors such as the introduction of beneficial microorganisms to the culture medium (Galmés et al, 2011;Nascente et al, 2017a,b;Santini et al, 2018;Buzo et al, 2019;Santos Júnior et al, 2019), can result in greater growth, which can increase productivity. Therefore, the mixed treatments of BRM32114 + pool of T. asperellum, 1301 + Ab-V5 and Ab-V5 + pool of T. asperellum stood out and provided the upland rice plants with higher values both in the photosynthetic rate and in the carboxylation efficiency.…”

“…Content of macronutrients in biomass of upland rice plants, cultivar BRS A501 CL, submitted to the inoculation of beneficial microorganisms, isolated or in mixture * -Significant difference from the control treatment by the Dunnett test at p ≤ 0.05; averages followed by the same letter do not differ by the LSD test (p ≤ 0.05); 1 to 26 -Number of treatments; The black bar refers to the control treatment. Treatments: isolated BRM32114 (1); isolate BRM32110 (2); pool of T. asperellum (3); isolate 1381 (4); Ab-V5 isolate (5); isolate 1301 (6) and mix BRM32114 + BRM32110 (7); mix BRM32114 + 1381 (8); mix BRM32114 + pool of T. asperellum (9); mix BRM32114 + 32110 + Ab-V5 (10); mix 32110 + Ab-V5 (11); mix 32110 + T. asperellum pool (12); mix 32110 + Ab-V5 + pool of T. asperellum (13); mix Ab-V5 + pool of T. asperellum (14); mix BRM32114 + pool of T. asperellum (15); mix 1381 + 1301 (16); mix 1381 + Ab-V5 (17); mix 1301 + Ab-V5 (18); mix 1381 + BRM32114 (19); mix 1301 + BRM32114 (20); mix 1381 + 32110 (21); mix 1301 + 32110 (22); mix 1381 + T. asperellum pool (23); mix 1301 + pool of T. asperellum (24); mix BRM32114 + BRM32110 + 1381+ pool of T. asperellum + 1301+ Ab-V5 (25) and control (without microorganism) 26water and nutrients, which can provide greater resistance to environmental stresses, such as increased temperature, reduced relative humidity, reduced porous soil space, and increased salt concentration (Chagas et al, 2016;Rosa et al, 2020;Pereira et al, 2020;Santini et al, 2018;Buzo et al, 2019;Santos Júnior et al, 2019).…”

Azospirillum brasilense Inoculation in a Maize–Urochloa–Rice Cropping System Promotes Soil Chemical and Biological Changes and Increases Productivity

“…In the municipality of Selvíria-MS, Brazil, researchers observed a 19% increase in grain yield under an irrigation treatment for upland rice inoculated with A. brasilense compared to the treatment without inoculation [55]. In the same municipality, it was reported that the inoculation of seeds with A. brasilense, with or without fertilization at 50% of the recommended nitrogen dose for the crop (10 kg ha −1 at sowing + 40 kg ha −1 at topdressing), increased the grain yield of rice compared to the treatment without inoculation [56]. Similar results were found in the present study, which included topdressing with ammonium sulfate as the N source, at a dose of 60 kg ha −1 , and the inoculation of seeds with this plant-growth-promoting bacterium.…”