Arid and semi arid plants biotechnology.pptx

this ppt provides idea about the biotechnology of arid and semiarid plants.

1. Arid and semi arid plants biotechnology

2. Arid and semi-arid areas are defined by the amount of rainfall they receive. Arid regions receive less than 10 inches (25 centimeters) of rain per year, while semi-arid regions receive 10 to 20 inches (25 to 50 centimeters) of rain per year. The northern arid regions in India comprise largely of the desert of Rajasthan, the Rann of Kutch and the semi-arid regions of Punjab and Gujarat . The Southern arid regions are in the rain shadow of the Western Ghats covering states of Maharashtra, Karnataka and Tamil Nadu .

3. What plants grow in arid and semi soil? These soils are very infertile, but with proper fertilizers and irrigation, the drought resistant and salt tolerant dry crops such as  barley, cotton, wheat, millets, maize, pulses , etc., can be grown . The semi-arid tropics include some of the most highly populated areas of the world and the region produced over half of the world's sorghum , over 80 per cent of the pearl millet, over 90 per cent of the chickpea and pigeon pea and over 60 per cent of the groundnut.

4. What are the characteristics of arid plants? Xerophytic plants Have extensive root systems Reduced transpiring surfaces A layer of cuticle, and other anatomical characteristics that protect the plant from the arid atmosphere. Stress of arid and semi – arid land: Salinity and drought as major abiotic stresses

5. The International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) was created in 1972 to address the challenges associated with "growing marginal crops on marginal lands with marginal resources". The challenges for agriculture in the semi-arid tropics are to: (1) improve the productivity of the subsistence crops that include coarse grains such as sorghum and millet, and food legumes such as cowpea, groundnut, and pigeon pea. (2) Improve and protect the assets and resources of the poor farmers living in this agro -ecological zone (3) build partnerships with local organizations to enhance and protect natural resources

6. ICRISAT has focused its work following a four-point mandate to Improve the most important crops of the semi-arid tropics and safeguard their seeds Develop improved farming systems Find ways to overcome agricultural constraints Collaborate with local organizations in participatory research and technology exchange with farmers The genetic resources available in the crops grown in the semi-arid tropics has provided the source of genes for their betterment.

7. Biotechnology of arid and semi arid plants involve the following research goals: Rescuing and preserving endangered crop biodiversity, Identifying important characteristics for resistance to biological and environmental stresses, Improving breeding populations with these new characteristics as a vehicle for sharing them with NARS, and last but not least Introducing and applying biotechnology protocols to overcome constraints unable to be tackled by conventional cross-breeding methods. The identification, isolation and cloning of new genes controlling specific characteristics will also facilitate the development of a more stable, diversified germplasm with improved resistance to diseases and pests, stress tolerance, better food quality, and higher productivity .

8. Advances by ICRISAT and its research partners in applied crop biotechnology Tissue culture in cereals Genetic transformation in legumes Integrated pest management and transgenic crops Diagnostic tools for, and DNA fingerprinting of pathogens DNA markers and gene cloning

9. A new technique to develop homozygous plants of pearl millet in a single generation, known as dihaploids , has been recently adapted (ICRISAT 1999). Cultured spikelets generate double haploids from female gametes. Doubled haploids of agricultural plants are produced in vivo by parthenogenesis or in vitro by isolated microspores culture, anthers, unfertilized ovules. The plants derived by using this method can set seed normally, survive, and reproduce outside the laboratory, thus shortening the breeding cycle to produce uniform lines, and accelerating the development of new cultivars. Plant regenerations from mesophyll-derived protoplasts of sorghum, and from embryonic cell suspensions of wild sorghum have been reported. These results may enhance the utilization of sorghum protoplasts for gene transfer. Tissue culture in cereals

10. It is focused on incorporating resistance genes not available in primary gene pools into existing genotypes to overcome major biotic constraints. These research include the development of shoot regeneration by tissue culture that will be used for genetic transformation with improved efficiency. Protocols are being fine tuned to introduce cloned foreign genes through selected tissue culture systems and Agrobacterium tumefaciens -mediated gene transfer. The enhancement of resistance to Botrytis gray mold of chickpea using polygalacturinase inhibiting protein (PGIP) genes. Regeneration and transformation of chickpea using Agrobacterium tumefaciens based binary vectors. Regeneration and transformation of chickpea and pigeonpea to improve the nutritional status of these pulse crops by introducing genes for lysine and threonine, as well as insect and pathogen resistance using lectin genes. Genetic transformation in legumes

11. Integrated pest management and transgenic crops With the advent of genetic transformation techniques, it has become possible to insert genes into the plant genome that confer resistance to insects. Among the biological pesticides, bacteria such as Bacillus thurigiensis ( Bt ) and B. sphearicus have been the most successful group of organisms identified for use in pest control on a commercial scale. Bt genes have now been incorporated into crops such as cotton, soybean, maize, potato, rice, broccoli, lettuce, walnut, apple, and alfalfa. Insecticidal genes such as Bt , trypsin inhibitors , lectins , ribosome inactivating proteins , secondary plant metabolites, vegetative insecticidal proteins, and small RNA viruses can also be used alone or in combination with Bt genes for pest control. Insecticidal genes as those derived from Bt and plant genes such as protease inhibitor from soybean and pigeon pea are used for transformation of pigeon peas and chickpeas.

12. DNA fingerprinting of pathogens reveals their genetic variability (Sastry et al., 1995), so appropriate resistance can be deployed in advance. Molecular markers help unravel patterns of diversity in crops and their wild relatives. DNA markers are used to evaluate the genetic variation in gene banks, as well as to identify phylogenetic and molecular structure of crops and their associated wild species. Molecular-assisted genetic analysis provides a means to locate and select genes controlling important agronomic, disease-resistance, and food quality traits