Growth of castor bean (Ricinus communis L.) cultivars under different water levels in the soil

Abstract

Castor bean (Ricinus communis L.) is a plant species with good prospects for biodiesel production, but its irrigated crop limited by the lack of specific information about its water requirement. The objective was to evaluate the growth of castor bean cultivars under different soil water contents. Therefore, we conducted the experiment in a protected environment by studying the effect of four levels of soil water content (40%, 60%, 80% and 100% of field capacity) on two castor bean cultivars (cv. Paraguaçu and cv. Nordestina) in five replications in a randomized block design. Evaluated were plant height, number of leaves, stem diameter, root volume, besides the production of fresh biomass, and dry. Although we calculated the ratio of leaf, weight ratio and root / shoot. In both cultivars, plant height, number of leaves and stem diameter increased significantly (30.07% and 30.02%, 18.75% and 23.23%, 39.00% and 36.00 %) between the lowest and highest level of hydration respectively. The increase in soil water availability benefits the growth of castor bean cultivars and increases the production of dry matter, also affecting growth rates.