Aperfeicoamento do sistema de producao de melancia em areas irrigadas.

A cultura da melancia, variedade Charleston Gray, vem se comportando muito bem no submedio Sao Francisco, no Nordeste do Brasil, a producao estilar vem limitando o desenvolvimento da cultura na regiao, provocando perdas que podem atingir 40% da produtividade. Este trabalho apresenta os resultados de um estudo conduzido com dois tratamentos, um modificado e outro tradicional. Este representou a temologia dos produtores, aquele utilizou as inovacoes tecnologicas recomendades pela pesquisa. O principal resultado obtido com o tratamento diz respeito a reducao da podridao estilar.

Viability of irrigation by porous capsule method in arid and semi-arid regions.

This paper presents the results of four field experiments carried out with the objetive of evaluating the feaibility of irrigation by porous capsule method, from 1979 to 1983, at Bebedouro Experiment Station, EMBRAPA-CPATSA, Petrolina, PE, Brazil. The irrigation system consisted of fulcrum of cone shaped porous capsules, interconnected with conduit pipe and installed in the soil at equidistance and 0.10 m deep along contour lines. The hydrostatic pressures studies did not significantly influence the crop yield, but influenced, at 0.10 level, the daily water release from porous unit. The mean yields for watermelon (Citrullus vulgaris Shard), var. Charleston Gray, for muskmelon (Cucumis melo L.) var. Valenciano Amarelo, and for maize (Zea mays L.), var. Centralmex, estimated in ton/2,500 units/ha or in cobs/2,500 units/ha, were 28.5, 10 and 17,500, respectively. The water consumption for watermelon, musk melon and maize was, respectively, 60 mm, 60 mm and 100 mm in a deep sandy yellow-red latosol. The cost of the system was US$ 1.677,41/ha.