Produtividade e crescimento da mamoneira em plantio adensado sob diferentes níveis de irrigação

Abstract

Presented as an alternative for biodiesel production without direct competition in the food market, the castor bean crop has received more attention in an attempt to improve agricultural profitability. Some techniques which had not previously been considered are now receiving increasing investigation, such as high density of plant population and irrigation. This present study aimed to evaluate castor bean yield and growth characteristics in the field with narrow row spacing, and under irrigation based on different levels of soil water tension. The research field was located in the Climatology and Agrometeorology sector, of the engineering department at the University of Lavras. The evaluated period was from March to September of 2010. The plant spacing was 0.30m between plants and 0.70m between rows. The stem height, plant diameter, seed weight with and without berry were evaluated. A completely randomized design with five treatments and four replications was used. Treatments were without irrigation (T0); and irrigation starting at soil matric potential values of 15 (T1), 30 (T2), 45 (T3), and 60 kPa (T4). Treatment T1 presented the highest yield and growth. This treatment showed 4700 kg ha-1 and the control without irrigation just 460 kg ha-1.