Fertilizers with coated urea in upland rice production and nitrogen apparent recovery

Abstract

Urea is the most used N fertilizer for upland rice, however, a great percentage of N loss can occur with the use of this fertilizer. The use of products that provide reduction of N loss for urea fertilizers can contribute to increase N use efficiency. The objective of this study was to determine the effect of N rates applied in the form of coated urea in the content and accumulation of N in dry biomass, apparent recovery of nitrogen and grain yield of upland rice. The experimental design was a randomized complete blocks arranged in a 4 x 3 + 1 factorial scheme. The treatments consisted of four sources of N fertilizer [1. Common urea; 2. Polymer-coated urea for slow release of N (PCU); 3. urea with the urease inhibitor N-(n-Butyl) thiophosphoric triamide (NBPT); and 4. urea coated with copper sulfate and boric acid as urease inhibitors (UCCB)], with three fertilization rates (30, 60 and 90 kg ha -1 of N). In addition, we included a control treatment without N application. Coated urea did not provide increases in rice grain yield in relation to common urea. The increasing amount of N resulted in significant increases in rice grain yield (from 3217 to 5548 kg ha -1 , 2010/11, and from 3392 to 4560 kg ha -1 , 2011/12). The apparent nitrogen recovery rate decreased with the increase in N applied doses.

Productivity of corn and beans as affected by season and source of nitrogen

“…This fact shows that for the conditions tested, coated urea sources behave similarly to urea. Similar results were obtained by Bernardes et al (2015) and Silva Junior et al (2020) with beans, by Carvalho et al (2016) and Fageria and Carvalho (2014) with rice, by Prando et al (2013) with wheat, and by Silva et al (2012) with corn. Thus, it appears that under the conditions of this study, the modifications made to urea aiming to increase its efficiency were not effective in providing higher yields of corn and common bean grains in the two years evaluated, since urea provided results that were similar to those provided by other sources.…”

“…The use of nitrogen provided significant increases in corn and common bean yields. Likewise, Fageria (2014), Carvalho et al (2016) also reported an increase in the grain yield of agricultural crops with the use of N in Brazilian Latosols. Nitrogen is an important nutrient in crop development, and the use of nitrogen fertilizers in crops is directly related to increased yield (FAGERIA, 2014).…”

“…Nitrogen (N) is one of the most dynamic nutrients in the soil, being more susceptible to losses (CARVALHO et al, 2016;NASCENTE et al, 2014;MORO et al, 2013), and the low efficiency of the agronomic use of this nutrient, which is observed in most agricultural systems, is partially a result of volatilization and losses associated with the nitrification of N, such as those caused by leaching and denitrification of N-NO 3 - (FAGERIA, 2014). The efficiency of the processes of N use and loss in the soil-plant system has both economic and environmental consequences, especially when N-oxides are emitted into the atmosphere.…”

Yield-scaled greenhouse gas emissions in subtropical paddy rice treated with stabilized nitrogen fertilizers

“…All treatments led similar grain yields, so the stabilized fertilizers provided no advantage over urea in this respect. Carvalho et al (2016) assessed N topdressing with urea in relation to fertilizers such as urea + NBPT, zeolite-coated urea and urea coated with Cu and B applied to aerobic rice and obtained similar results.…”

“…However, some authors have found exponential increases in N 2 O emissions depending on the N fertilizer rate used (Shcherback et al, 2014). Nitrogen fertilizer management and starting ooding up to 3 days after N application is the ideal combination to maximize nitrogen use e ciency while minimizing N losses (SOSBAI, 2014; Carvalho et al, 2016). This can explain the similarity of seasonal N 2 O emissions among fertilizers in GS2, when all SNF performed similarly to common urea.…”