Cocoa and cashew

Abstract

The tropical plant cocoa (Theobroma cacao L.), the source of chocolate, is endemic to Amazon basin. Its cultivation has subsequently extended to tropical and subtropical regions of South and Central America, West Africa, and Asia Pacific. In cocoa, an effective stomatal regulation facilitates the trees to withstand moisture stress during summer months. Morphological and anatomical adaptations also favored the accessions during drought conditions. Development of rapid screening methods for stress tolerance and identification of promising accessions for selective breeding has been done. Biochemical parameters like waxes that impart stress tolerance in some of the accessions have been well delineated. Carbon sequestration studies have indicated that cocoa has potential in climate change issues. Higher CO2 and temperature levels influenced photosynthetic characteristics. Cashew has gained economic importance because of its export potential. Cashew (Anacardium occidentale L.) is a native of northern part of South America and introduced into India in the sixteenth century. In west and east coast regions, cashew is grown under rainfed conditions. The regions where cashew is grown generally receive 3000–4000 mm of rainfall. Screening of cashew germplasm at three different agroclimatic regions has resulted in identification of few drought-tolerant lines. Detailed studies on photosynthesis in relation to drought, irrigation, and fertilizers have been done and results discussed.