Intensive cropping of lowland rice in some regions of Santa Catarina, Brazil

Abstract

Intensive cropping of irrigated rice (Oryza sativa L.) in the Lower and Middle Itajaí River and north coast regions in Santa Catarina State, Brazil, may be done through either double cropping or rattoon cropping. Experiments were carried out at the EMPASC/Experimental Station, during the 1977/78, 1978/79, and 1979/80 crop seasons, to determine the best time to seed the first and second cropping, and the best soil management system for the second cropping in comparison to ratoon cropping. The first cropping seeded between 20.9 and 10.10 had the most stable productions (5.7 to 6.8 t/ha). The second cropping, 20.1 to 5.2, showed higher production when seeded by the middle of January, with an average of 4 t/ha. The mean production for the first cropping (9.9 to 10.10) was 3.4 t/ha; production for cropping seeded between 20.2 and 10.3 occurred only in the third year. Among the tillage systems for second cropping, minimum tillage was similar to conventional tillage, with productivity of 3.7 t/ha. The no-tillage system, with 3.3 t/ha, gave lower production in comparison to the other two systems, but economically was the same as for rattoon cropping. Productivity of rattoon cropping varied with the time of the original cropping. It reached a 3 t/ha average in the three periods. The productions observed were about 50% of the original cropping.