Interactive effects of genotype x year on disease reactions, grain yield and other agronomic traits of newly developed quality protein maize in Nigeria

الملخص EN

Experiments were conducted on six newly developed open pollinated quality protein maize (QPM) genotypes and two check entries for three years (2009-2011).

The objective was to assess their yield potentials and disease tolerance/ resistance in the southern Guinea savanna agro-ecology of Nigeria.

Genotype and year of evaluation were significant for (P<0.01 and <0.05) for grain yield, harvest moisture and lodging characteristics.

Genotypes x year interactive effect for grain yield revealed different genotypic performance of the genotypes tested with two checks (Oba-Super 1 and DMRLSR- Y) being responsible for the significant differences obtained in the three years of evaluation.

Average grain yield was significantly higher in the year 2011 compared to 2009 and 2010.

All the genotypes tested were moderately tolerant to the five diseases ranging from 1.5 (Streak virus) in Oba-Super 1 (check) to 2.9 (Southern leaf blight, Curvularia leaf spot and Leaf rust) in the ART98-SW6-OB and ART98-SW4-OB respectively.

Ear rot mostly affected the leaves among diseases with a range of 2.3 to 2.8 in TZPB-OB and DMR-LSR-Y respectively..

Four QPM genotypes (ART98-SW5-OB, ART98-SW4-OB, TZPB-OB and ART98-SW6-OB) were superior for grain yield with yield advantage of 28% over the best OPV check.

These QPM genotypes can therefore serve as useful replacement for existing cultivars and also as source of genes for future maize breeding activities in the development of superior maize varieties with high protein contents for the savanna agro-ecology.