French bean (
To achieve this, we initiated an induced mutagenesis program. Seeds from the village seed stock were subjected to treatments with varying doses of ethyl methane sulfonate (EMS) ranging from 0.1% to 0.4% and sodium azide (SA) from 0.1% to 0.4%. The objective was to increase yield potential and enhance genetic diversity.
The treatment with EMS and SA led to a non-specific, dosage-independent reduction in biophysiological characteristics in French bean mutants. Notably, the 0.4% SA treatment significantly inhibited germination and fertility, causing a decrease in chlorophyll (10.02 mg. g-1 FW) and carotenoid (1.57 mg. g-1 FW) levels. This suggests a disruption in genes associated with chlorophyll and carotenoid synthesis. However, in the M2 generation, the mutagenic treatments substantially improved yield and associated traits. The highest pod yield per plant was recorded at 79.50 gm for the 0.2% EMS treatment. A character association study revealed strong correlations (0.217 to 0.995) between pod yield and other agronomic traits.
The results indicate that selecting mutants based on these traits in populations treated with EMS and SA can significantly increase crop yield. The 0.2% SA and 0.2% EMS M2 mutant populations exhibited the highest induced variability, making them ideal for selecting higher-yielding mutant lines for further breeding generations. The increased yields in these mutant lines, derived from a local cultivar, show promise for meeting the growing demand for French bean production through their widespread cultivation.