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CRITÉRIOS PARA A SELEÇÃO DE LINHAGENS DE SORGO EFICIENTES E RESPONSIVAS AO FÓSFORO Полный текст
2014
FABRICIO RODRIGUES | JURANDIR VIEIRA DE MAGALHÃES | CÉSAR AUGUSTO BRASIL PEREIRA PINTO | FLÁVIO DESSAUNE TARDIN | ROBERT EUGENE SCHAFFERT
The optimization of nutritional efficiency is critical to increase productivity and reduce produc- tion costs. However, the identification of lines with greater efficiency and responsiveness to phosphorus is of great importance, with the in intention to join the hybrid, these traits at once and, moreover, the best way to select them. Thus, the objective of this study was to evaluate which characters should be considered in the se- lection of genotypes efficient and responsive to phosphorus in sorghum. The correlations were split into direct and indirect basic variables of efficiency and responsiveness to phosphorus through path analysis. The character that most influenced the efficiency of sorghum lines to phosphorus was harvest index to utilization efficien- cy and dry matter to absorption efficiency and use, under conditions of stress. Under conditions of adequate phosphorus fertilization, the trait with the greatest influence for evaluation of responsiveness was dry grain mass to the apparent recovery efficiency, physiological and agronomic.
Показать больше [+] Меньше [-]IMPACTO DO CULTIVO DE CITROS SOBRE A QUALIDADE FÍSICA DE UM ARGISSOLO AMARELO EM SERGIPE Полный текст
2014
DANIELLE VIEIRA GUIMARÃES | MARIA ISIDÓRIA SILVA GONZAGA | ELOÁ MOURA ARAÚJO | JOSÉ DE OLIVEIRA MELO NETO | JOSÉ ILMAR TÍNEL JÚNIOR
Agricultural use of soil resources under irrigated conditions requires constant monitoring of the soil quality attributes due to important soil functions related to soil water storage and distribution, aeration and root growth. The present study aimed to evaluate the impact of citrus cultivation, under irrigated conditions, on the physical quality of a Yellow Ultisol through determination of soil pore size distribution, bulk density and soil water retention, in the Neópolis flat land irrigated perimeter, Sergipe. Soil core samples were collected from the 0-0,10 m, 0,10-0,30 m and 0,30-0,50 m layers, with three replications, in a 15 ha citrus orchard. The same soil type under native forest was also evaluated as a reference of soil quality. It was observed reduction in soil total porosity, macroporosity as well as available water as a function of citrus cultivation. Such alterations in soil physical quality influence negatively root development and plant productivity and also call attention to the need of soil quality monitoring as well as best irrigation management practices. Evaluation of soil quality under native forest was efficient in showing the magnitude of soil alterations as a result of changing in soil use.
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