ABSTRACT

Ten genotypes of maize (Zea mays L.) were evaluated for tolerance to soil acidity in a field experiment conducted at the Michael Okpara University of Agriculture experimental farm Umudike. The genotypes were collected from International Institute of Tropical Agriculture (IlTA), Thadan. The genotypes included: SUWAN-I-SR, TZL Comp3C3, TZL Comp4C4, TZU TSR- Y, ATP SR-Y, ATP SYN C5, ATP SYN Dilly, TZU TSR- W SGY, TZB- SR- SOY, and the local check Bende white which was collected from Umuhia. The experiment was laid out in a Randomized Complete Block Design (RCBD) and replicated three times during the 2007 cropping season. The farm size was 180m2and each plot measured l.5m x 4m. The spacing was 75cm between rows and 50 cm within rows. Bende white had the highest ear height and at maturity was the tallest while SUWAN- I- SR had the shortest ear height and also had the shortest plant height at maturity. The }ighest number of leaves was recorded by the following genotypes: ATP SYN C5, ATP SYN DillY, and TZ!J TSR -W SGY.SU WAN- I- SR and TZL Comp4C4had the lowest number of leaves. SUWAN- 1- SR and ATP- SYN C5 had the lowest number of fresh cobs while TZU TSR- W SGY had the highest fresh cob weight. TZL comp.1C4 sulked earlier than the others while ATP SR- Y sulked last. TZL Comp3C3had the highest grain yield while SUWAN-!- SR had the lowest grain yield. The following genotypes TZL Comp3C3, TZL Comp4C4, ATP SR-Y, ATP SYN Dill Y, TZU TSR-W SOY, and TZB-SR-SGY, that yielded above one tons per hectare (it/ha) and were better than the check (Bende white) can be said to be tolerant to the acid soils of Umudike. Results obtained showed that TZL Comp3C3was significantly different (P< 0.05) from Bnde white in grain yield.