Fertilizer distribution mechanisms and side dress nitrogen fertilization in upland rice under no-tillage system

Abstract

Some crops have shown not to adapt to the no-tillage system (NTS) as a consequence of the compaction of the superficial soil layer. In a certain way, the mechanism used in seeders to open furrows for the deposition of fertilizers can have great importance in facilitating root penetration. This study was carried out to evaluate the influence of two fertilizer distribution mechanisms and N fertilization in upland rice (Oryza sativa) under NTS. The experiment was carried out in the growing seasons 2001/2002 and 2002/ 2003, in Botucatu, state of São Paulo, Brazil. A completely randomized block design was applied, with subdivided plots and four replications. Main plots consisted of two furrow opening mechanisms (furrow opener and double disk). Subplots consisted of four side dressing N levels (0, 40, 80 and 120 kg ha -1 ). The following parameters were evaluated: furrow and seed deposition depth, plant population, plant height, number of stems and panicles m -2 , number of spikelets per panicle, spikelet fertility, weight of 1,000 grains, shoot dry matter, grain yield and N levels in the flag leaf. The success for upland rice establishment under the NTS in dry winter regions of Brazil is directly associated to the furrow opening mechanism of the seed-drill. The furrow opener mechanism resulted in deeper seed deposition, consequently decreasing seedling population, number of panicles per area and grain yield. Side dressing N fertilization in upland rice under NTS increases grain yield whenever the double disk mechanism is used to sow. Key words: Oryza sativa L., furrow opener, double disk, N doses Mecanismos de distribuição de fertilizante e adubação nitrogenada em cobertura no arroz de terras altas em sistema plantio direto RESUMO: Algumas culturas têm pouca adaptação ao sistema plantio direto (SPD), em vista da alta compactação da camada superficial do solo. Nesse caso, o mecanismo utilizado na semeadora para a abertura dos sulcos para deposição do fertilizante pode ter grande importância no sentido de facilitar a penetração das raízes. Avaliouse a influência do mecanismo de distribuição de fertilizante e da adubação nitrogenada na cultura do arroz de terras altas (Oryza sativa) no sistema plantio direto. O experimento foi conduzido nos anos agrícolas 2001/ 2002 e 2002/2003, em Botucatu-SP, Brasil. O delineamento experimental foi em blocos casualizados, com parcelas subdivididas e quatro repetições. As parcelas foram constituídas por dois mecanismos de distribuição de fertilizantes (haste sulcadora e disco duplo). Nas subparcelas, quatro níveis de N foram aplicados em cobertura (0, 40, 80 e 120 kg ha -1 ). Avaliou-se a profundidade de abertura do sulco e de deposição das sementes, a população de plantas, a altura de plantas, o número de colmos e de panículas m -2 , o número total de espiguetas por panícula, a fertilidade das espiguetas, a massa de 1.000 grãos, a matéria seca da parte aérea, a produtividade e o teor de N na folha bandeira. O sucesso no estabelecimento da cultura do arroz de terras altas n...

Water mimosa (Neptunia oleracea Lour.) can fix and transfer nitrogen to rice in their intercropping system

“…2, Table 2). Similar studies reported that these growth indicators increased with more N supply in the soil 31,32 …”

“…Similar studies reported that these growth indicators increased with more N supply in the soil. 31,32 In addition, our study revealed that the length of water mimosa in the NB treatment was higher than that in MB and SB treatments (Fig. 2(J), and (L)).…”

Intercropping of Rice and Water Mimosa (Neptunia oleracea Lour.): A Novel Model to Control Pests and Diseases and Improve Yield and Grain Quality while Reducing N Fertilizer Application

“…As a comparison, previous research found that crop yield increased with N fertilizer levels [40,41]. It is acknowledged that higher grain yield was obtained due to higher panicle numbers [40]. Similar to rice yield, reduced and conventional N treatments also had higher rice effective panicle numbers than zero N treatments (Table 1).…”

“…In the present research, compared with zero N treatment, the reduced and conventional N treatments substantially increased the yield of rice and water mimosa (Table 1). As a comparison, previous research found that crop yield increased with N fertilizer levels [40,41]. It is acknowledged that higher grain yield was obtained due to higher panicle numbers [40].…”

Nitrate reductase, micronutrients and upland rice development as influenced by soil pH and nitrogen sources

“…However, upland rice grain yield at NTS is lower than in the conventional tillage (Crusciol et al 2010;Kluthcouski et al 2000). One explanation given for the decrease in crop grain yield would be the low-nitrate assimilation capacity of rice seedlings, due to the low activity of the nitrate reductase (NR) enzyme in the early development phase, prior to the tillering stage (Araújo et al 2012).…”