Performance of the cotton variety BRS-336 under different seed densities

Abstract

This research was done to measure the effect of spacing between rows and plants on the growth, development, and production of the cotton variety BRS-336. Twelve plant densities were used: 55 556, 37 037, 27 778, 50 000, 33 333, 25 000, 45 455, 30 303, 22 727, 41 667, 27 778 and 20 833 pl ha-1, with single row planting arrangements. A randomized complete block design, in factorial arrangement (A x B), with four replications was used. The variables recorded were daily height increase (cm/day) in budding stage, plant height (cm), stem diameter (mm), crop canopy closure (days), internode length (cm), leaf greenness index (SPAD), number of cotton bolls opening/plant, number of open cotton bolls/plant, number of unopened cotton bolls/plant and yield of raw cotton (kg ha-1). The results obtained in the research indicate that spacing between plants (m) was significantly influential in most of the agronomic and productive variables, compared to the spacing between rows, while the interaction was not significant. The plant spacing of 0.2 m showed the best plant development in the growth stage. The spacing of 0.2 m between plants recorded the lowest values in the productive traits, whereas spacing with 0.3 m and 0.4 m reported the best behavior. The spacing of 1.1m between rows and 0.3 m between plants showed the best Marginal Rate of Return for cultivated cotton with the variety “BRS-336”. The combination of the studied factors registered higher values in agronomic and productive variables when compared to the control treatment (conventional spacing used by farmers).