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- Administrator Team
- Posts: 582
- Joined: Fri Apr 01, 2011 6:53 pm
- Nationality: Pakistani
- Location: گوجرانوالہ، پاکستان
Plant breeding is the art and science of changing the genetics of plants for the benefit of mankind. Plant breeding can be accomplished through many different techniques ranging from simply selecting plants with desirable characteristics for propagation, to more complex molecular techniques.Plant breeding has been practiced for thousands of years, since near the beginning of human civilization. It is now practiced worldwide by individuals such as gardeners and farmers, or by professional plant breeders employed by organizations such as government institutions, universities, crop-specific industry associations or research centers.Classical plant breeding uses deliberate interbreeding (crossing) of closely or distantly related individuals to produce new crop varieties or lines with desirable properties. Plants are crossbred to introduce traits/genes from one variety or line into a new genetic background.Traits that breeders have tried to incorporate into crop plants in the last 100 years include:1.Increased quality and yield of the crop2.Increased tolerance of environmental pressures (salinity, extreme temperature, drought)3.Resistance to viruses, fungi and bacteria4.Increased tolerance to insect pests5.Increased tolerance of herbicidesSteps of Plant BreedingThe following are the major activities of plant breeding;1.Creation of variation2.Selection3.Evaluation4.Release5.Multiplication6.Distribution of the new varietyPlant breeding programs in PakistanLocated at the western end of the South Asia subcontinent, Pakistan enjoys a wide variation in geography, soil, altitude and climate. Therefore farmers grow a diversity of crops with adaptation ranging from tropical and subtropical to temperate climates. But 70% of the cultivated area is occupied by wheat, rice, cotton, sugarcane, chickpea and maize. Agriculture is the mainstay of Pakistan’s economy contributing 22% to national GDP.There are at least 23 public research institutions involved in plant breeding and biotechnology, many of which are specialised in single crops. Although there are more than 600 registered seed companies (mostly small), very limited activities in plant breeding are being carried by the private sector. Almost all the breeding either through conventional or biotechnological tools is carried out in the public sector.An efficient and competitive sustainable agriculture ensuring food security, and with ability to contribute to the economic development is the main focus of plant breeders and biotechnologists. Most of the breeding activities are linked to major crops (wheat, rice, cotton, sugarcane). The biotechnological approaches are also used in wheat, cotton, hybrid maize and sunflower. Almost all the crops are confronted with many biotic (diseases, insects and pests) and abiotic problems (drought, salinity, high temperature and climate change), so breeding efforts are focused on their improvement for higher yield and sustainable productivity by fighting against the stresses.RESEARCH ACTIVITIES (On-Going) In Pakistan•Developing high frequency regeneration system and transformation in rice and wheat.•Genetic improvement of wheat and rice for drought and salt tolerance through marker-assisted selection and genetic transformation.•DNA finger printing of traditional and improved cultivars of wheat and rice.•Genetic transformation of potato for induction of disease resistance against fungal pathogens and production of disease free potato seed through tissue culture.•Transgenic Tomato with resistance to bacterial wilt.•Production of virus free banana plants through tissue culture. Status of cotton harboring Bt gene in Pakistan.•Production of inter-specific crosses in rice through embryo rescue.•Marker-aided selection of rice genotypes for resistance to bacterial blight in rice.•Transgenic plant production of rice for bacterial blight resistance gene.•Identification and molecular characterization of important microbes.ACHIEVEMENTS IN PLANT BREEDING•Banana crop in Pakistan is under severe threat of banana bunchy top virus (BBTV). The only way to replace infected fields is by healthy banana plants. More than one thousand disease free banana plants were produced through tissue culture technology and tested at different locations in Sindh. Banana plants have been transformed with marker gene while induction of resistance against BBTV is in progress•Production of pre-basic seed potato through tissue culture. This technology was disseminated to the provincial research institute, farmers and the private sector. The cumulative impact of the technology resulted in the decline of seed potato imports. Chitinase (antifungal) gene has been successfully transformed in potato variety cardinal and transgenic plants showed complete resistance to Fusarium and partial to Phytophthora. The molecular analysis revealed the presence of chitinase gene in transgenic potato plants.•Agrobacterium mediated transformation has been achieved in commercial grown cultivars of tomato (Roma) for bacterial wilt resistance.•Yellow Rust, drought and high temperature are major causes for decline in the production of wheat in Pakistan. Agrobacterium tumefaciens mediated transformation protocol has been established by using two days mature embryos as explant source in local varieties, which include Inqilab-91 and Chakwal-97.•Bacterial leaf blight caused by Xanthomonas oryzae (Xoo) is one of the major bacterial destructive diseases of rice, which causes loss of 50%. This is soil born and chemical control is difficult. We transformed rice Basmati-385 with Xa21 gene. The transgenic lines have been produced which are under evaluation.•A survey was conducted in the cotton growing areas of Sindh and Punjab provinces to assess the status of Bt cotton during July-August, 2007. Ten districts in Sindh and 11 districts in Punjab were surveyed and samples were collected from 126 various field sites. In laboratory, ImmunoStrip analysis and ELISA revealed that 80% samples from Sindh and 90% samples from Punjab were positive for the presence of Bt-Cry toxin.•Protocol for inter-specific crosses was developed using embryo rescue technique and three wide crosses were produced across the incompatibility barriers: IR6 x O.nivara, Basmati 385 x O.nivara, KS282 x O.nivara.•More than 150 genotypes of rice and wheat were tested under hydroponic condition using different salinity levels. The same material is being tested in the hot-spot areas of salinity. The best performing genotypes will be subjected to microsatellite markers with the hope to get linkage.Mapping populations are being developed for QTL analysis for salt, drought and rust resistance in wheat.