Effects of nitrous acid on growth and yield of Digitaria exilis (Haller)

Abstract

Digitaria exilis seeds have several economic uses with long shelf life and impressive nutritional qualities. The crop is faced with problems of low yield and small- sized grains among others, thus, the crop is neglected and little information is available on its improvement by mutagenesis. This work assessed effect of Nitrous acid on growth and yield of Digitaria exilis. D. exilis seeds were exposed to 0.1M Nitrous Acid for varying time of 2 hr, 4 hr, 6 hr and 8 hr, untreated seeds were used as control. The seeds were sown after treatment with Nitrous acid and effect on the quantitative and qualitative characters studied. Germination and seedling survival decreased with increase in time of exposure. Plant height, number of leaves, tiller/plant, and leaf length were significantly reduced at 6 and 8 hrs of treatment. All treatments induced early maturity but with low seed set and yield among 6 and 8 hr plants. Generally, the performance of the treated plants was better with short exposure time and 4 hr of treatment produced best agronomical traits and improved yield. Erect plants were obtained with 2 and 4 hr treatment which is a promising trait for mechanical harvesting of the crop. This study concluded that 4hr of exposure of D, exilis to 0.1M Nitrous acid could induce useful variability for improvement of the crop in a breeding programme.

Keywords: Digitaria exilis, early maturity, growth and yield, mutation breeding, nitrous acid, seedling survival