Variation studies of morphological characters of cashew trees (Anacardium occidentale) on Kogi State University Campus, Anyigba, Kogi State, Nigeria

Abstract

Variability could exist in a typical cashew field for most morphological characters and such morphological characters have been used as a powerful tool in the classification of cultivars and as such morphological traits continue to be the first step in the studies of genetic relationships. In this research work using morphological traits effort was made to access the variations among sixty (60) randomly selected trees from different locations across Kogi State University campus, from Faculties of Management Sciences, Natural sciences, Social sciences, Law, Agriculture and the Botanical garden. Morphological characters from Cashew descriptors by International Board for plant Genetic Resources (IBPGR) were used to determine the variations among the trees. Results indicate variations among trees on the campus, the dominant fruit shape observed was conical-obovate, the dominant fruit colour observed was yellow with a high percentage (71.67%), the dominant nut weight was intermediate (5-6 g), the dominant shape of leaves in the sampled population is obovate with 43.33%, the dominant leaf apex shape was rounded with 41.6%. The tree habit is quite variable with upright and open habit having 50%  while upright and compact habit have the least 15%. Three cashew descriptors were not observed in the trees on campus which are very low nut weight, cylindrical apple shape and pointed leaf apex shape. Variations were also observed in fruiting time, flower colours. Variation could be attributed to genetic history, though molecular studies would be needed to ascertain the genetic nature of observed variations.