Adubação fosfatada em tomateiro industrial em solos do Submédio São Francisco

Abstract

Phosphorus fertilisation on processing tomato in soils of the Submédio S. Francisco River Valley.Results of eight field experiments carried out in irrigated areas of the Submédio São Francisco River Valley, Northeast Brazil, from 1988 to 1993, were statistically analysed to evaluate the response of processing tomato (Lycopersicon esculentum, Mill) to phosphorus fertiliser, in soils with different available phosphorus contents by the methods of Mehlich -1 or Bray -1. The analysis showed that in soils where available P content was equal to or lower than 2 mg.dm -3 , the mean increment in tomato yield due to P fertilisation was 190.8%, while in soils where the P content was 8 mg/dm 3 , the increment was only 21.7%. However, in soils with P content equal or higher than 14 mg dm -3 , there was no response of the tomato crop to phosphorus fertilisation. In the two experiments where a quadratic response was observed, the maximum economical yields of 56.47 and 69.35 ton. ha -1 of tomatoes were obtained with 143 and 182 kg.ha -1 of P 2 O 5 , respectively.

Doses De NPK Em Tomateiro Cv. Marmande E Seu Desempenho a Campo No Cerrado

“…A deficiência de N durante o período de frutificação reduz a produção e altera a coloração dos frutos (GENUNCIO, 2009). O P é exigido em pequenas quantidades durante a fase de florescimento e frutificação, sua deficiência inicia-se com um menor desenvolvimento das plantas, seguido de clorose nas folhas (FARIA et al, 1999). Segundo Alvarenga (2004) a adubação potássica pode aumentar em 30% a produtividade do tomateiro, pois impede a queda e melhora a qualidade comercial dos frutos.…”

Effect of phosphorus (P) doses on tomato seedlings production in poor nutrients substrates and its importance on fruit yield

“…Nishimoto et al (1977) observed that P contents in tomato leaves ranged from 3.0 to 5.0 g/kg, when reaching their maximum yield of 95%. Faria et al (1999), evaluated the production of industrial tomatoes with phosphate fertilization in soils with different phosphorus levels; reported that in soils where available P content was equal to or lower than 2 mg.dm -3 , productivity increased (about 191%); however, soils where available P content was equal to 8 mg dm -3 , it only increased 22%. Moreover, soils where available P content was equal to or greater than 14 mg dm -3 , no response was observed.…”