Abstract:
Ultraviolet radiation and acridine orange has been widely applied in agriculture for inducing
genetic variability within plant species to be used in crop improvement, via induced oxidative
stress in plant cell. Therefore, this study aimed to increase genetic variability in field pea (Pisum
sativum L.) to choose the desired traits for crop improvement which depends on the presence of
many genetic variations in the population. In this study one genotype of field pea was exposed to
seven doses of physical and chemical mutagens to perform mutagenesis treatments. Over night
pre-socked fresh seeds in tap water and or in 200 ppm acridine orange were exposed to different
times of ultraviolet irradiation (UV) and then sown in the field. The dose of 45 minutes exposure
to UV revealed the maximum mean value in root length if compared with the control. The most
doses of mutagens observed significant decline in the number of nodules formed per plant, as
well as induced significant increase in the concentration of chlorophyll b. High values of
heritability coupled with high genetic advance as percentage of mean were obtained for plant dry
weight, plant fresh weight, root length, number of nodules formed per plant, leaf area,
chlorophyll a and chlorophyll b. This indicated the additive gene effect governed these traits and
the selection will be effective for improving them in breeding programs. Whereas, low
heritability estimates coupled with low genetic advance were obtained for the number of
branches per plant, total chlorophyll, as well as carotenoids in leaves and pods, indicating that
these traits were more affected by environmental factors. It is concluded that inducing genetic
variations in field pea is useful in designing breeding programs either by selection or crosses. |
