Application of lime, phosphogypsum and fertilization rates affect soil fertility and common bean development in no-tillage system in a Cerrado Oxisol

<p></p><p>ABSTRACT. There is a lack of information about the effects of interactions among lime, phosphogypsum (PG) and fertilization on soil fertility and their effects on common bean yields in the tropics. This study aimed to determine the effects of annual application of PG and limestone and rates of fertilization on the chemical attributes of soil, fertilization efficiency, yield components and the grain yield of the common bean. The study was performed for three growing seasons in an acidic Oxisol. The experimental design was randomized blocks in a 4x4 factorial scheme. The treatments consisted of lime, lime + PG, PG, and control (without corrective application) with four fertilization rates. In an acidic and low-fertility Cerrado soil, limestone or limestone + PG applied annually at 1/3 of the total rate in a no tillage system increased the common bean yield and the efficiency of the fertilization, although the improvement of the soil acidity indicators did not reach the desired levels. The application of soluble fertilizers to provide adequate and balanced amounts of nutrients provided greater yield gains and improved soil fertility compared to surface liming without fertilization, but the combination of the two practices resulted in the greatest benefits to both plant and soil fertility.</p><p></p

Performance of low phosphorus tolerant rice genotypes under drought stress

<div><p>ABSTRACT The identification of genotypes more tolerant to water deficit and more efficient in the use of nutrients little available in the soil is an important low-cost strategy to promote sustainable agriculture in marginalized regions. In this sense, a study was carried out in the SITIS Phenotyping Platform of the Embrapa Arroz e Feijão, with the objective of evaluating the drought tolerance of upland rice genotypes tolerant to phosphorus (P) deficiency. The experimental design was performed in a randomized complete block with split-split plots and two replications. In the plots were established two water regimes (with and without water deficit), in the subplots two soil phosphorus contents (25 and 200 mg dm-3) and in sub-subplots 48 upland rice genotypes. The water deficit had more impact on grain yield than the phosphorus supply. The genotypes AB 062037, AB 062041, AB 062138, Arroz Mato Grosso, BRA 02601, BRA 052045, CNA 4098, CNA 6187, Guapa, Guaporé and Rio Paranaíba were classified in the most productive group under both water regimes. The most productive genotypes under water deficit showed higher root density in the deeper soil layers. The most productive genotypes in the two water regimes were also those that showed the highest transpiration.</p></div

Sowing time affecting the development of common bean cultivars in Lichinga, Province of Niassa, Mozambique

<div><p>ABSTRACT The demonstration of yield potential of crops depends on genetic factors, favorable conditions of envi ronment, and management. The sowing time can significantly affect the common bean grain yield. The aim of this research was to study the behavior of Brazilian cultivars and sowing times on the yield components and grain yield of common bean grown in the environmental conditions of Lichinga, Province of Niassa, Mozambique. The field trial was performed for two growing seasons, using the experimental as a randomized block in factorial 5 × 3 × 2, with four replications. The treatments consisted of the combination of five common bean cultivars (BRS Pontal, BRS Agreste, Perola, and BRS Requinte, developed by Brazilian Agricultural Research Corporation (Embrapa), and a local variety, Encarnada) with three sowing dates (beginning of the rainy season, and 15 and 30 days after), during two growing seasons. The Brazilian cultivar of common beans BRS Pontal was the most productive in all sowing times, followed by BRS Agreste, which was not the most productive only in the second sowing time of 2013/2014 growing season. The cultivar Encarnada, from Mozambique, was the less productive cultivar in all sowing times and in all growing seasons. The best sowing time for common bean cultivars is in the beginning of the rainy season. The use of technologies such as use of seeds of new cultivars, proper sowing time, fertilization, and control of weeds allow significant increase of common bean grain yield in Lichinga, Mozambique.</p></div

Yield of cotton as a second crop in narrow planting in response to nitrogen and potassium fertilization

<p></p><p>ABSTRACT Nitrogen and potassium are the most required nutrients for cotton crop. Cotton grown as a second crop, after soybean harvesting, has been an option for crop system in the Brazilian savanna. This study aimed to evaluate the effect of N and K fertilization on the nutritional status and the yield components of cotton grown as a second crop, after soybean, and in a narrow planting system. The experiment was carried out adopting a completely randomized block experimental design. The treatments were set up in a 4 × 4 factorial arrangement with four replications. Factor A was the four N doses (0, 50, 100, and 200 kg ha-1) and factor B was four K2O doses (0, 40, 80, and 160 kg ha-1), applied as side-dressing. The N and Mg concentration levels in the leaf increased linearly with the N doses, while the concentration levels of S and Fe decreased (quadratic effect). The K2O doses resulted in positive and negative effects on K and Mg, respectively, in the leaf. The N fertilization promoted higher lint yield response when compared with K fertilization, as lint yield rate per kg of N was twice the yield rate per kg of K2O. The highest lint yields were reached with 148 kg ha-1 and 107 kg ha-1 of N and K2O, respectively.</p><p></p