Observations on progenies in a crossing scheme between cashew clones: establishment characters

Abstract

A study was conducted to establish the genetical basis of the characters of importance in cashew production Six clones held in the Tanzanian cashew germplasm collection, but of diverse origin, were selected for study. They were selected on the basis of showing phenotypic variation in a number of the main characters of agronomic interestas well as comprising one that was susceptible, and the other five putatively showing tolerance, to powdery mildew. These six clones were selfed and crossed in as many combinations as possible. This required that suitable techniques were developed to allow controlled pollination to be carried out. The Crossing programme resulted in progenies of 13 hybrid combinations and 5 selfs. These were planted in 4 replications of 12-tree plots in the field at Naliendele Agricultural Research Institute, Mtwara, Tanzania along with vegetative propagules of the parent clones. Tree heights and canopy diameters were recorded three years after planting. The results showed that the growth of the seedlings was more vigorous than the clonal propagules of the parental clones. It was found that height was more highly heritable than canopy diameter at this stage in the establishment and hence would be more readily manipulated by selection in a breeding programme.

Keywords: cashew, crossing programme, height, canopy diameter, heritabilities

-Tanzania J. Agric. Sc.,(1999) Vol. 2 No. 1, 1-6