Abstract

YIELD EVALUATION OF OPEN POLLINATED SWEET POTATO (Ipomoea batatas (L) Lam) GENOTYPES IN HUMID ENVIRONMENT OF UMUDIKE, NIGERIA

Nwankwo IIM, Bassey EE, Afuape SO

Field experiments were conducted in 2012 and 2013 cropping seasons to evaluate fourteen open pollinated sweet potato genotypes of the final stage of Uniform Yield Trial (UYT) for yield and yield related traits, root skin and flesh colours. The sweet potato genotypes were EA/11/031, EA/11/022, EA/11/014, EA/11/024, EA/11/026, EA/11/018, EA/11/030, EA/11/017, EA/11/003, EA/11/001, UM/11/002, EA/11/007, EA/11/005 and TIS87/087 as check. The sweet potato characters studied were plant count at harvest, total root tuber number, large root tuber number, small root tuber number, number of root tubers per plant, total root tuber yield (t/ha), large root tuber yield (t/ha) and small root tuber yield (t/ha), and root skin and flesh colours. Significant differences were observed for all the metric characters (P≤0.05). Ten genotypes produced total root tuber yields which were higher than the check variety and could be listed for Advanced Yield Trial, namely: EA/11/022, EA/11/002, EA/11/030, EA/11/018, EA/11/031, EA/11/026, EA/11/005, EA/11/017, EA/11/003 and EA/11/001. Four of them however gave root tuber yields greater than 11 t/ha and were classified as moderate yielding genotypes, namely: EA/11/022, EA/11/002, EA/11/030 and EA/11/018, although none was classified as high yielding genotypes (18 – 30 t/ha) at Umudike, Nigeria. Three genotypes namely: EA/11/007, EA/11/014and EA/11/024 recorded root tuber yield of less than 11 t/ha and could be eliminated from the list of sweet potato for advanced yield trial. All the moderate yielding genotypes however were the cream fleshed types which could be crossed with the -carotene rich varieties for development of -carotene – high yielding hybrid varieties for the environment