Comparison of vegetative growth and tuber yield of potato (solanumtuberosum l.) from seedling tubers derived from true potato seed (TPS) with those from conventional seed tubers of parental clones

Abstract

A study to show potato (Solanum tuberosum) tuber yield from seedling tubers derived from true potato seeds (TPS) as planting material was carried out between March 1994 and January 1995 at the Kabete Field Station University of Nairobi. Seedling tubers of hybrids and openpollinated progenies were compared with the conventional seed tubers of the parental lines and local standard clones on the basis of vegetative growth, total and marketable tuber yields and tuber characteristics (size, shape and colour). A split plot design experiment with three replicates was used in the study. Vigour of plants from local standard clones was higher at the early stage of .growth, whereas plants from the advanced imported varieties had higher vigour in the later slages of growth. Seed tuber size, sprout uniformity and seasonal changes had significant effects on the number of main stems per hill. Plants derived from hybrid seedling and convenlional seed tubers showed significantly higher number than the rcsl. Tuber yields from hybrid seedling tubers were significantly (P=O.05) higher than those from the open pollinated seedling tubers and convenlional seed tubers. Marketable yield indicated that conventional seed tubers out yielded seedling tubers. However, local standard clones gave significantly (P=O.05) lower yield than seedling tubers despite their tuber uniformity. Results of tuber characteristics showed that there was segregation for skin colour, size and shape of the tubers from seedling tubers. The uniformity of the tubers from conventional seed tubers was better than that from seedling tubers. Tuber uniformity from the hybrids tended to be better than that from open pollinated progenies.