**2.2 Viable mutations**

208 Gamma Radiation

crop, or as a mixed crop. It is cultivated in areas with annual rainfall 300-600 mm, but does not tolerate flooding or water logging. The favourable average temperature is 18 to

The use of dry seeds of horsegram as human food is limited due to its poor cooking quality, presence of high level of enzyme inhibitors and heamagglutinin activities (Ray 1969). The seeds are rich in tannins and polyphenols compared to the other legumes (Kadam and Salunkhe 1985). Antinutrients like phytates, tannins and oxalic acid reduce the availability

The authentic seeds of horsegram (*Macrotyloma uniflorum* (Lam.) Verdc) cultivar Dapoli Kulthi-1 were procured from Head, Department of Botany, College of Agriculture, Dr. Balasaheb Savant Konkan Agricultural University, Dapoli, Dist-Ratnagiri (M.S.) India.

The field experiments were conducted on the experimental field at Department of Botany, University of Pune, Pune 411 007 (M.S.). The crop of horsegram Dapoli Kulti-1 was grown in *Kharif* season under uniform conditions. All the experiments were carried out in triplicate, following RBD design. The size of each plot was 3.75m X 2.75m and each plot had 225 plants. The distance between two rows and two plants was 30 X 15 cm and the distance

A total of 42 combination treatments in M1 generation with untreated dry seeds, which was used as control. Final 675 seeds of each treatment were used to raise M1 generation. The M2,

The chlorophyll mutants were scored from 7 to 10 days after sowing. The different types of chlorophyll mutants such as albina, xantha, chlorina and viridis were reported in all

Amongst all the treatments used gamma radiations had induced the highest chlorophyll mutation frequency, followed by combination treatments. Prakash and Halaswamy, (2006) and Manigopa-Chakraborty *et al*., (2005) and Bolbhat and Dhumal (2009) have also reported

The frequency of total chlorophyll mutants varied for single as well as combination of gamma radiation and EMS. In gamma radiation the average percentage of chlorophyll mutation frequency was 1.47% which was slightly higher than combination treatments (1.23%). The highest chlorophyll mutation frequency was recorded in 200Gy (1.70%). The values of chlorophyll mutation frequency were ranging from 1.09% to1.70%. Amongst all types of chlorophyll mutations, albina and chlorina types showed higher percentage

induction of chlorophyll mutation in horsegram with GR and their combination.

27ºC, and adapted to a wide range of well-drained soils.

of iron.

**2. Results** 

**2.1 M2 generation** 

mutagenic treatments.

**2.1.1 Chlorophyll mutations** 

**1.1 Experimental layout** 

between two adjacent plots was one meter.

M3, M4 and mutants were raised in next rainy season.

Results obtained in the present investigation are discussed in brief.

The mutations affecting gross morphological changes in plant habit, leaf and pod morphology, and maturity were scored as viable mutations. These mutants were characterized and named on the basis of specific characters constantly observed in them throughout the course of investigation. Viable mutants and their characteristic features are given in Table-2. Effect of mutagens on the frequency and spectrum of different types of viable mutations in M2 generation is illustrated in Table-1.
