Mutation has been utilised to improve growth and yield of many food crops, but only little effort has been made to ascertain the nutritional advantages in such improved crops. The present study evaluates the alkylating efficiency of sodium azide of different concentrations on pod yield, nut size and nutritional composition of two groundnut varieties. Dry seeds of groundnut ( Arachis hypogea L.); Samnut 10 and Samnut 20 varieties obtained from the Ministry of Agriculture, Ilorin, Kwara State of Nigeria were treated with different sodium azide concentrations (10, 20, 30, 40 and 50mM) for 12 hours. Seeds soaked in distilled water for 12 hours were used a s control for each variety. The treated seeds and control were sown in planting bags in ran domized complete block design with three replicates. Alkylating effects of the treatments were studied on pod parameters and nut size while proximate analysis was carried out on the nuts to determine their nutritional composition. The results showed that sodium azide treatment of 50 mM produced significantly taller plants with more branches and leaves. Analysis of collected data revealed that sodium azide is effective in achieving significantly earlier- maturing plants with higher pod yield, bigger nut size and heavier nuts. All concentrations of Sodium azide applied induced significant higher crude protein and fat with respect to control in samnut 10 while 50 mM yielded highest protein and fat in samnut 20 variety. Generally, nutritional values of the studied groundnut were improved by sodium azide treatments with respect to protein and fat content which are the most important constituents in groundnut utilization as foo d or raw material for edible oil. The study concluded that the alkylating effect of s odium azide was effective on pod yield, nut size and other nut characteristics of groundnut and could be employed to improve protein, crude fat and other nutrition contents of t he nuts for human and animal consumption as well as industrial applications.

Objective: Mutagenesis has been used in several crop improvement programmes but only on a very limited scale for Digitaria improvement and in order to further strengthen the existing conventional improvement methods, we report enrichment of Digitaria exilis variability by exploiting the effects of gamma radiation of different doses on yield and growth of the crop. Methodology and Results: Digitaria exilis seeds were exposed to gamma irradiation (20Gy, 40Gy, 80Gy, and 100Gy) from 60 Co source and irradiated seeds were sown for evaluation. The effects of the irradiation doses were studied on germination, seedling characters, growth, and yield parameters at maturity. Days to emergence and percentage germination were enhanced at low irradiation doses with 80Gy producing optimally. Plant height, tillering and number of leaves were significantly affected by gamma irradiation and analysis of obtained data showed irradiation significantly affects percentage seed-set, number of spikes/tiller and number of spikelets/spike. Also, early maturity was achieved among irradiated plants and 100-grain weight was highest at 80Gy. Conclusion: Plant from 80Gy irradiation dose performed optimally for all the characters evaluated in this study. Hence, 80Gy or slightly low dosage form of gamma irradiation using cobalt (60) could be utilised to increase variability and yield in Digitaria exilis. The new or modified traits so created could be screened for the possibility of isolating and selection of mutants that are promising for further improvement breeding programmes.

ABSTRACT:Litter production and decomposition rates have great importance in maintaining the fertility of the soil. The study was carried out to determine the relationship tree characters (girth size, canopy radius, tree height, leaf area and number of primary branches), litter production and quality, and climatic variables among stands of Daniellia oliveri (Rolfe) Hutch. & Dalziel growing in University of Ilorin campus. Twelve trees of different girth sizes were selected and their physiognomic characters measured. Litter samples (leaves and twigs) were collected from the stands on monthly basis (January to May) using 1 m 2 traps. The collected litters were air-dried, ground and analysed for carbon, nitrogen, phosphorus, potassium, calcium and magnesium using standard methods. Rainfall and temperature data were collected during the sampling months. Girth size range was 0.32 -0.67 m. Tree height range was 13.90 -31.81 m. Primary branches range was 3 -16, crown radii was 2.5 -5.2 m and leaflet area between 24.62 cm 2 and 90.90 cm 2 . Higher leaf litter was recorded in January and February, but twigs were more in the other months. Leaf and twig litters positively correlated with girth size (r = 0.572 and 0.614 respectively), but the former also correlated with crown radii (r = 0.834). Carbon, calcium and magnesium contents in leaves and twigs were lower in May compared to January, but reverse trend were observed for nitrogen and phosphorus. The number of rain (rainy days) negatively correlated with total monthly litter (r = -0.291). The study concluded that climatic conditions influence tree characters, which in turn affect litterfall and nutrient returns to the soil. ©JASEM