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The present study entitled “Development of dual purpose fodder cowpea [Vigna
unguiculata (L.) Walp] through mutagenesis” was conducted in the Department of Plant
Breeding and Genetics, College of Agriculture, Vellayani during 2019-2021. The study
was conducted to induce mutation in fodder cowpea, variety Aiswarya with Ethyl
Methane Sulphonate and to select superior dual purpose genotypes for seed and fodder
from the mutants.
The study was carried out in three experiments. In the first experiment, seeds of
fodder cowpea variety Aiswarya were treated with five different doses of EMS.
Observations were recorded on seed germination per cent and seedling survival per cent.
Germination percentage and seedling survival percentage reduced with an increase in the
concentration of the mutagen. Based on the seedling survival percentage, LD50 value
were determined. Effective doses were fixed as 0.35%, 0.39%, 0.43%, 0.47% and 0.51%
according to the LD50 value.
In experiment II, seeds were treated with the effective doses of EMS and M1 plants
were evaluated. Observations were recorded on seedling emergence (%), seedling
survival at branching stage (%), and plant survival up to maturity (%) and these
characters varied significantly among the treatments. Presence of chimera and
chlorophyll mutants was also observed. Presence of chlorophyll mutants were noted in
the population of all mutagenised treatments.
Seeds from M1 generation constituted M2 population. M2 generation was observed
for various quantitative characters including number of primary branches per plant,
number of leaves per plant, days to first flowering, days to 50% flowering, green fodder
yield per plant, dry matter yield per plant, leaf stem ratio, leaf dry weight per plant, stem
dry weight per plant, leaf area index, plant height, seed yield per plant and days to
maturity and qualitative characters like early plant vigour, plant growth habit, leaf
texture, leaf colour, flower colour, seed colour and presence of chlorophyll mutants.
Significant variations were found in all quantitative characters except plant height and
leaf stem ratio. Among these, number of primary branches per plant, number of leaves
per plant, green fodder yield per plant, dry matter yield per plant, leaf dry weight per
plant, stem dry weight per plant and leaf area index were higher in 0.43% EMS treatment.
Seed yield was found higher in control, which was on par with 0.51% EMS and followed
by 0.43% EMS treatment.
In qualitative characters, seed colour and plant growth habit showed remarkable
variation, whereas early plant vigour, leaf texture and leaf colour exhibited slight
variations. Flower colour did not show any variations. Comparing with M1, frequency of
chlorophyll mutants in M2 was lesser.
For fodder purpose, 0.43% EMS treatment expressed higher fodder yield. In case of
seed yield, 0.51% was recorded with higher seed yield, followed by 0.43% among the
mutants.
It was concluded from the present investigation that, for fodder cowpea variety
Aiswarya, which was treated with different concentration of EMS and 0.43% EMS
treatment was found effective to obtain superior genotypes for seed and fodder yield from
mutants.