Mutation Breeding

Food crops like rice, have been domesticated for thousands of years. Cultivation of specific rice varieties generation over generation for selected traits leads to loss of other beneficial traits and narrows down the genetic variability over time. Generating genetic variability through mutagenesis is an important tool to develop new varieties with different traits. Mutagenesis can be performed on a desirable genetic background and the mutant lines can be screened for beneficial traits like high nutrient content, disease resistance and high yields. The mutations associated with the beneficial phenotypes can be mapped by next generation sequencing (NGS) or micro-satellite markers.

Team
Kamal K Malukani, VS Sresty Tavva

Activities:

Trichosanthes dioica, also known as pointed gourd, is a dioecious species with male and female flowers observed in separate individual plants. It is mostly cultivated in the eastern and northern parts of India. The fruits are green with white or no stripes. These striped, green vegetables also called as parwal is rich in many nutrients, various antioxidants, Vitamin A, B1, B2 and C. On the other hand, Pointed Gourd is rich in fibre and low in calories which help in reducing and maintaining weight. Due to its dioecism, cross pollination is inevitable for fruit setting. Hand pollination in female flower is widely practiced and must be completed early in the morning. Though pointed gourd vegetable has several health benefits, the production happens at very low scale due to the plant being dioecious and the pollination must be completed very early in the morning.

The aim of this project is to generate hermaphrodite (flowers containing both female and male organs) pointed gourd (Parwal) lines and evaluate their agronomic performance under both greenhouse and field conditions. The mutant line developed through EMS mutagenesis produces both hermaphrodite and female flowers; so, it is required to first study the flowering pattern and extent of fruit setting under greenhouse and field conditions. Since Parwal is a perennial and a vine (creeper) plant, detailed analysis can only be done on field grown plants. Therefore, TIGS is collaborating with University of Agricultural Sciences, GKVK, Bengaluru to carryout field experiments and to generate and evaluate hermaphrodite parwal plants.

Investigator: V S Sresty Tavva

Collaborators:
University of Agricultural Sciences (UAS), GKVK, Bengaluru

Most of the traditionally grown varieties of rice are rich in carbohydrates but do not provide adequate amounts of micronutrients such as iron, zinc and proteins. We aim to screen rice lines generated by mutagenesis for beneficial traits like low glycemic index, and high iron, zinc and protein content. We are testing rice mutant lines previously developed by CSIR-CCMB in collaboration with ICAR-IIRR as well as freshly mutagenized rice lines.

We have screened over 200 mutant lines for iron and zinc concentration in the grains. In the initial screening, some mutants show higher zinc concentrations in the grains than their parents. We are screening the same lines in next generations to obtain pure lines. The lines that consistently show higher zinc will be used for the quantification of all the elements in the grains by other approaches.

As part of the collaborative work, we have also generated a new mutagenized population in the background of Improved Samba Mahsuri (ISM), the bacterial blight tolerant, low GI rice variety. We are generating stable lines which will be screened for various nutritional parameters.

Investigator: Kamal K Malukani

Collaborators:
CSIR – Centre for Cellular and Molecular Biology (CSIR – CCMB), Hyderabad
ICAR – Indian Institute of Seed Science (ICAR – IISS), Mau

Drought is one of the major abiotic stresses affecting the yield of crops. There are different strategies to enhance drought tolerance in plants. One of these is enhancing the plant root length. A Deeper root will be able to absorb water from deep soil which is helpful during drought conditions. Our collaborator at the University of California, San Diago has identified two plant secondary metabolites involved in root growth development. Treatment of seedlings with either of these metabolites enhances root growth in rice and tomato seedlings. We are testing if these metabolites also increase root growth in adult rice plants and if pretreatment of these compounds also increases root growth in plants. If the compounds do induce root growth in plants, they will be tested for providing tolerance against drought.

Investigator: Kamal K Malukani

Collaborators:
University of California, San Diego (UCSD)

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