Repeatability of Progeny Mean, Combining Ability, Heterosis and Heterobeltiosis in Early Generations of a Potato Breeding Programme

Thirty-three populations of Andigena potatoes developed by 11 × 3 (line × tester) mating were studied from seedling to third clonal generations for number of tubers, average tuber weight, tuber yield, plant vigour, predominant tuber shape, predominant tuber size and uniformity in tuber shape, uniformity in tuber size and uniformity in tuber colour. Inter-generation correlation coefficients for progeny means, general combining ability, specific combining ability, heterosis and heterobeltiosis were computed for various characters. Magnitude of inter-generation correlation coefficients showed that various parameters for uniformity in tuber shape, uniformity in tuber size, uniformity in tuber colour, predominant tuber shape and predominant tuber size could be reliably estimated in early generations starting from the seedling generation. The parameters for tuber yield, average tuber weight and tuber number could only be reliably estimated from second clonal generation onward. Repeatability of progeny means showed that negative selection for tuber yield and average tuber weight could be initiated from first clonal generation and for tuber number from second clonal generation. Plant vigour was found to be a highly inconsistent character.