RESUMOA utilização de reguladores vegetais em arroz pode proporcionar redução na altura de plantas e diminuir o acamamento. Objetivou-se verificar a influência da aplicação do regulador vegetal thidiazuron na cultura do arroz de terras altas, em região de Cerrado brasileiro. Utilizaram-se as cultivares BRS Esmeralda e IAC 202, bem como delineamento experimental de blocos casualizados, em esquema fatorial 4 x 3 para cada cultivar, constituído de doses de thidiazuron (0 g ha-1; 0,3 g ha-1; 0,6 g ha-1; e 0,9 g ha-1) e três épocas de aplicação (perfilhamento, diferenciação floral e emborrachamento), com quatro repetições. O número de espiguetas por panícula e fertilidade das espiguetas da cultivar BRS Esmeralda foram maiores utilizando-se a dose de 0,9 g ha-1 de thidiazuron, com aplicação na fase de perfilhamento. A massa de 100 grãos da BRS Esmeralda se ajustou a uma equação quadrática, enquanto, para a IAC 202, houve ajuste a uma equação linear, com melhor época de aplicação durante o perfilhamento. Para massa hectolítrica da BRS Esmeralda, os resultados também se ajustaram a uma equação quadrática, enquanto, para a IAC 202, houve diferença significativa apenas entre as épocas, sendo o emborrachamento a melhor época de aplicação. As produtividades de grãos da BRS Esmeralda e IAC 202 apresentaram ajuste linear positivo, com ganhos de 23,5 % e 6,5 %, respectivamente, em relação à testemunha. O thidiazuron influencia positivamente na produtividade da cultura do arroz de terras altas.

The study was carried out in Selvíria-MS, in the 2011/12 and 2012/13 agricultural years, aiming to evaluate the efficiency of Azospirillum brasilense in nitrogen fixation in upland rice, as a function of doses and application methods of the inoculant containing this diazotrophic bacterium. The experimental design was randomized blocks, arranged in a 4 x 4 factorial scheme, with 4 doses of inoculant (control without inoculation, 100, 200 and 300 mL of the commercial product ha-1) and 4 application methods (seed inoculation, application in the sowing furrow, soil spraying after sowing, and foliar spraying at the beginning of plant tillering), with 4 replicates. During the experiment, the agronomic characteristics, production components and yield of the rice crop were evaluated. It was concluded that the inoculant containing Azospirillum brasilense promotes increase (19%) in the yield of upland rice under sprinkler irrigation when used at the dose of 200 mL ha-1, regardless of the application methods.

Global rice (Oryza sativa L.) cultivation is expected to increase, especially in upland no‐tillage systems (NTS). The difficulty in producing and maintaining straw in NTS in the Brazilian Cerrado and comparative regions worldwide can be overcome by using cover crops in irrigated areas. The potential of straw accumulation, soil cover maintenance, and nutrient cycling is considered while choosing cover crop species, because these characteristics may interfere with subsequent crop cultivation. This study was conducted to determine whether cover crops could benefit the development, productivity, and industrial quality of upland rice grains irrigated by sprinklers and cultivated in succession. The experiment was conducted in the Cerrado, with a summer rainy season and a dry winter. The treatments consisted of six cover crops (millet [Pennisetum glaucum], sunn hemp [Crotalaria juncea], pigeonpea [Cajanus cajan], millet + sunn hemp, millet + pigeonpea, and fallow) sowed in winter or spring. Compared to fallow, the cover crops cultivated in winter or spring led to increased straw production, accumulation of approximately 150% more nitrogen in straw, and possibly improved rice nutritional value because of the higher N content. Rice plants cultivated after sunn hemp developed a greater dry mass than rice cultivated after the fallow treatment. Grain yield was not influenced by the cover crops. However, sunn hemp cultivation increased the milling yield, head rice yield, and the milled rice productivity (MRP), compared to cultivation following the fallow treatment. Cultivation of sunn hemp before the upland rice crop improved MRP compared to that following the fallow treatment.

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The corn crop is one of the most cultivated in the world and one of the most need studies that seek alternatives on the use of Azospirillum brasilense. This bacterium produces growth hormones that may benefit the corn crop. The work objective was to verify the agronomical performance of corn crop, in function of foliar Azospirillum brasilense inoculation, associated with nitrogen doses. The research was performed in Selvíria, Mato Grosso do Sul State, Brazil, which is in the Brazilian Cerrado. The corn crop was cultivated during season (Spring/Summer) and late season (Summer/Autumn), under conventional tillage system. Experimental design of randomized blocks was used, with factorial scheme 4 × 2. The treatments were made in four nitrogen doses (0, 30, 60 and 90 Kg ha-1) with and without the foliar applying (in stage V6) of the inoculant containing A. brasilense. The inoculant used had the strains AbV 5 and AbV 6 of A. brasilense (2×10 8 viable cells mL-1) and, the dose 200 mL ha-1 was used. The nitrogen fertilization was made with ammonium sulfate, also on phenological stage V6. The following evaluations were made: Final plant population, foliar nitrogen content, foliar chlorophyll index, ear insertion height, plants height, stalk diameter, ears length, ears diameter, thousand grain weight and grain productivity. The foliar inoculation with the A. brasilense bacterium proved to be advantageous for the corn crop, and therefore, an option for the farmer. Because of the large volume of products used in seed (fungicide, insecticide, plant growth regulators) and the lack of information on the degree of interference of these products on the bacteria, it becomes pertinent the study of other inoculation forms on crops. Other studies that verify the influence of A. brasilense bacteria in foliar application on the physiology of the shoot and root of crops should be encouraged.

The previous cultivation of green manures and mechanical soil decompression are options to minimize compaction of the topsoil in no-tilage system (NTS) set in different production systems in the Brazilian Savannah. In addition, it is essential to relate these agricultural practices with the economic benefits generated through the production cycles. The objective of this study was to evaluate economically the effect of sporadic mechanical decompression of the soil and previous cultivation of green manure in the production and net gain margin of upland rice and "winter" common bean, under sprinkler irrigation, in NTS in lowland Brazilian savannah. This study was developed in the 2012/13 harvest and 2013 winter in Selvíria, state of Mato Grosso do Sul, in an clay texture Oxisol in the savanah in the state of Mato Grosso do Sul, in a randomized block design arranged in a 5 x 2 factorial arrangement with four replications. The treatments were a combination of five green manures (fallow (control), Cajanus cajan, Crotalaria juncea, Pennisetum glaucum and Urochloa ruziziensis) with and without mechanical soil scarification. The yields of upland rice and common bean grains were not influenced by the previous green manure cultivation; the upland rice grown in succession to Cajanus cajan in the presence of mechanical soil scarification provided greater increase in grain yield and higher gross margin profit. Beans cultivated in succession to Crotalaria juncea and Pennisetum glaucum in the presence of mechanical soil scarification, followed by rice cultivation, provided greater increases in grain yield and gross profit margins.

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...