Seed yield and oil quality of perennial castor bean in a Mediterranean environment

Document Type: Research Paper

Authors

1 Dipartimento di Scienze delle Produzioni Agrarie e Alimentari (DISPA), Università degli Studi di Catania, Via Valdisavoia 5, 95123 Catania (Italy).

2 CNR-Istituto per la Valorizzazione del Legno e delle Specie Arboree (IVALSA), UOS di Catania, Via P. Gaifami 18, 95126 Catania (Italy)

Abstract

ewline"> Castor (Ricinus communis L.) is an oilseed species, which in southern Italy is
cultivated as annual during the spring-summer period under irrigation, but in most
temperate areas such as those of eastern coast of Sicily, it could be grown as semiperennial with no irrigation, by the adoption of autumnal sowings. A field
experiment was conducted in southeastern Sicily with the aim of assessing plant
surviving, seed yield and oil quality of four castor genotypes originating from
different geographical areas (two Sicilian, one Tunisian and one Brazilian). The
favorable climatic conditions allowed the plant to survive during the fall-winter
period. Seed yield reached 3.45 t ha-1 on average of the two years and seed oil
content ranged from 45% (Tunisian cultivar) to 48% (‘Local RG 2’ Sicilian
genotype). Oil yield reflected the variation in seed yield. Genetic diversity for fatty
acid composition and saponification number, iodine value and cetane number was
evidenced. When ricinoleic acid is not taken into account, the oil of all genotypes
satisfied the EU standards for biodiesel. The ricinoleic acid was the lowest (79%)
in the Sicilian ‘Local RG 2’ and the highest (89%) in the Tunisian one, revealing a
greater suitability of oil of the first genotype for biodiesel. In turn, the oil of
Tunisian genotype could be exploited in other bio-based industrial sectors. The
study also demonstrated that in the southeastern coast of Sicily autumnal sowings
might be advantageous for castor grown as semi-perennial crop, mainly since they
allow saving irrigation water.

Keywords