489 resultados para retenção de nitrogênio


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The use of sewage sludge is a practice highly promising for the development of sustainable agricultural systems. The objective of this study was to assess the improvement in soil fertility management strategies on different sewage sludge and mineral nitrogen after seven application of this residue. The experiment was carried at the Sao Manuel Experimental Farm belonging to the faculty of Agronomic Sciences of UNESP, Botucatu, located in the county of Sao Manuel. It was adopted the experimental design in a randomized blocks consisting of six treatments and five repetitions defined as follows: T0 - without nitrogen fertilizer, T1 - mineral fertilizer nitrogen according to the crop needs, T2 - 50% nitrogen from sewage sludge and 50% in the form of chemical fertilizer, T3 - 100% of nitrogen recommended by the culture, from sewage sludge, T4 - 150% of nitrogen recommended by the culture, from sewage sludge and T5 - 200% of the nitrogen from the sewage sludge. It has done seven application of sewage sludge in crop ( year 1 - sunflower, year 2 sunflower, year 3 - oats and bean, year 4 - triticale and sunflower, year 5 - wheat) and the first three applications were treated with sewage sludge and the other applications were composted sludge. In the depth 0-20 cm, the sewage sludge promoted an increase in levels of organic matter, P, S, H+Al, CEC and decreased in soil pH. In the depth of 20 to 40 cm the sewage sludge promoted a decrease in pH and increase in soil organic matter, P, H+Al, K, Ca, SB, CEC and S. Mineral N influence the increase in the depth S of 20-40 cm.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aims of this study was evaluated the efficiency of nitrogen sufficiency index (NSI) calculated with base on the measures relative chlorophyll index (RCI) leaves, measured with portable chlorophyll meter, as an indicator of time of sidedressing N fertilization and verify which value of NSI (90% and 95%) is the most appropriate to indicate the moment of N fertilization on common bean cultivar IAC Alvorada. An experiment with five N managements (M1: 200 kg ha(-1) N (40 kg at sowing + 80 kg at 15 days after emergency (DAE) + 80 kg 30 DAE); M2: 100 kg ha(-1) N (20 kg at sowing + 40 kg at 15 DAE + 40 kg at 30 DAE); M3: 20 kg ha(-1) N at sowing + 30 kg ha(-1) when chlorophyll meter readings indicated NSI < 95%; M4: 20 kg ha(-1) N at sowing + 30 kg N ha(-1) N when chlorophyll meter readings indicated NSI <90% and, M5: control (without N application)) and four replications was carried out in the rainy and dry growing seasons of the agricultural year 2009/10, in Botucatu, Sao Paulo State, Brazil. The variables RCI, aboveground dry matter, leaf N concentration, yield components, grain yield, and N use efficiency were evaluated. The NSI of 90%, calculated based on monitoring of RCI in common bean leaves with chlorophyll meter, was more effective than 95% to define need for N sidedressing in common bean cultivar IAC Alvorada, reducing the N application and improving the use efficiency of applied N.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Pós-graduação em Zootecnia - FCAV

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Pós-graduação em Agronomia - FEIS

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)