Seedling selection in open pollinated genotypes of cashew (Anacardium occidentale)

Abstract

In a highly heterozygous crop like cashew (Anacardium occidentale L.), selection of high yielding trees from a seedling population of existing varieties is one of the ways of development of variety. Hence an experiment was undertaken to study the extent of variability in seedlings of six popular genotypes, viz. NRCC Sel 2, Vengurle 4, Vridhachalam 3, Bhaskara, VTH 174 and VTH 30/4 and to identify promising trees. Eighty open pollinated seeds each from trees belonging to six genotypes were collected; seedlings were raised and planted during 2007 at Directorate of Cashew Research, Experimental Station, Shantigodu. Growth parameters like trunk girth, tree height, tree spread and nut yield per tree were recorded. The progeny performance in different varieties revealed that the mean nut yield per tree was highest with 2.46 kg in Vridhachalam 3. With regard to individual tree performance tree number 480 belonging to VTH 30/4 recorded highest yield of 6.9 kg nuts/tree. The frequency distribution patterns showed that data of trunk girth was moderately negatively skewed implying increasing alleles are in slight excess and dominant for this trait. Whereas tree height and tree spread distributions were moderately positively skewed indicating decreasing alleles are in slight excess and dominant for these traits. The nut yield showed highly positively skewed distribution revealing decreasing alleles are in excess and dominant. The kurtosis was very high for nut yield indicating that yield variability is due to a few extreme differences from the mean. It was observed that trunk girth and tree spread were positively correlated with nut yield. The study could identify one promising seedling (T No.480), a seedling progeny of VTH- 30/4 in terms of nut yield.