Efforts Towards The Development Of High Yielding And Stem Borer Resistant Maize In A Humid Environment

ABSTRACT

Field experiments were conducted at the Teaching and Research Farm of the Department of

Crop Science, Faculty of Agriculture, University of Nigeria, Nsukka to commence the

process of developing high yielding maize with resistance to stem borers in a humid

environment. The specific objectives were to (i) screen some maize genotypes for agronomic

traits and stem borer resistance (ii) estimate some genetic parameters of the genotypes

studied. Twenty maize genotypes used comprised twelve maize genotypes collected from the

International Institute of Tropical Agriculture (IITA) namely (2009 TZE OR1 DT STR QPM

(TOR1), AMA TZBR - Y - F2 (AMA), TZBR COMP - 2 - YC1F2 (COMP2), BR 9928

DMRSR (B28), DMR - LSR – Y (DMR), TZE - Y - POP DT STR QPM (POP), 2009 TZE

OR2 DT STR QPM (TOR2), 99 TZE Y - STR QPM (99 TZE), BR 9943 DMRSR (B43),

TZBR COMP - YC1F2 (COMP1), EV DT - Y - 2000 STR QPM (EVDT) and TZEE - Y -

POR STR QPM CO (PORC)) and eight (8) local accessions (Ugwuachara (UG), Umukasi

(UM), ORBA1, Obukpa (OB), ORBA2, Edem Ani (EA), Isakpu (IS) and Ajuona (AJ)) from

Enugu state, Nigeria. The parameters measured include days to tasselling, silking, maturity,

stem girth, number of leaves, ear height, plant height, ear length, ear diameter, number of

kernel per row, number of rows per ear, number of kernel per cob, number of ear per plant,

shelling percentage, ear weight, grain yield, brown spot disease, lodging incidence, stem

borer infestation, number of exit holes and tunnel damage length. General combining ability

(GCA) of the parents and specific combining ability (SCA) of the hybrids were estimated

using Graffings’ model 1 method 2 in a 10 x 10 diallel cross. Among the parents, POP and

PORC had significantly (p < 0.05) shorter days to tasselling (55.67 and 56.00) and silking

(57.00 and 58.33), respectively than other genotypes. The parent UG had significantly (p