Impact of Abiotic Stress on Quality Traits of Maize Forage at Two Growth Stages

Maize (Zeamays L.) forage quality traits are reported to show varying responses to abiotic stress. Four trials were conducted in Sudan (Africa) during the summer and winter seasons (2013 – 2014) at two locations: Shambat (normal soils) and Soba (salt affected soils) to investigate the effects of abiotic stress on the nutritive value of maize forage. In each trial nine maize genotypes were studied under two watering regimes arranged in split plot experiment in randomized complete block design. The compound effect of salt, water and heat stresses created by the combination of locations, seasons and watering regimes were used to investigate the effect of abiotic stress on forage quality at silk initiation and dough growth stages. Character associations under stressed and none stressed conditions were studied. NDF, ADF, CP, forage yield and related traits were measured. Abiotic stress significantly lowered the nutritive value in terms of crude protein, digestibility and intake potential. Digestibility under stressed condition was slightly improved as growth stage advanced from silk initiation to dough stage. Correlations under non stress conditions between forage yield and quality traits were either favorable with NDF and weak or insignificant with ADF and CP. Under stress conditions, similar trend generally exists apart from the unfavorable correlation of CP with each of yield and ADF, in addition to earliness with NDF. The compound effect of salt, water and heat stresses have adverse impact on the nutritive value of maize forage. Varieties combining high performance in quality and forage yield could be developed under non-stressed or stressed conditions.