The importance of planting configuration and the sorghum cultivar intercropped with annual cotton

Abstract

In the Gurinhém area of Paraíba, Brasil, a test was carried out in 1983 to determine the influence of various planting configurations when two sorghum cultivars (IPA 10 and ICAPAL), grain and forage sorghum, respectively, were intercropped with annual cotton (Gossypium hirsutum L.r. latifolium Hutch.) cultivar CNPA-2H. The soil in the area is an associated vertisol. The experimental design was in completely randomized blocks with four replications and nine treatments involving three configurations of intercropping plantings. The configurations were: (1) Alternated rows of canon: sorghum; (2) double row of cotton: one row of sorghum; (3) three rows of cotton and one of sorghum cultivar, grown each one isolately. It was found that the system with double row of cotton (0.75 m x 0.20 m spacing) with one row of grain sorghum planted in a row 1 m apart from the cotton was the most efficient than cotton grown having the efficiency use index of 1.16%, the cost benefit ratio of 2.39, and 10.39 of increase in the net profit. None of the intercropping systems affected the cotton fiber characteristics. It was observed that the development of cultivar IPA 10 was more advanced up to the 50^th day after emergency than ICAPAL cultivar. This difference was measured by plant height main stem diamenter leaf area per plant, and leaf area index. At 75 days from emergency this situation was reversed.