Improvement means to make such modifications and amendments in the existing one that ultimately leads towards the best combinations. Crop improvement using biotechnology and genetic engineering is not a dream now. In last 10 years tremendous progresses have seen in the field of genetic engineering and biotechnology.
BIOTECHNOLOGY AS A KEY FOR CROP IMPROVEMENT
BY: SYED UMAER ANWER
Improvement means to make such modifications and amendments in the existing one that ultimately leads towards the best combinations. Crop improvement using biotechnology and genetic engineering is not a dream now. In last 10 years tremendous progresses have seen in the field of genetic engineering and biotechnology. The base line of this progress is the development of new techniques i.e. detection of useful genes, perfect gene transfer techniques, success in regeneration of new plant from a single cell, evaluation of first generation transgenic plants and the most important is the positive change in public perception about new advancements on molecular level that play a very vital role in development and acceptance of biotechnological and genetically modified commodities.
Enhance yield of field crops or in other ways increasing food production is always the chief priority of the breeders. Huge population growth rate have been seen in last decade worldwide. This rapid rise in population ultimately boasts the human needs such as food, shelter and clothes. In the past decade it has seen that high population growth rate cause a significant increase in urbanization and loose of valuable farmland. While trying to develop such hybrids and cultivars which are high yielding to follow demand of food breeders produce verities which are poor in nutrition and cooking quality. Biotechnology and genetic engineering offer powerful tools in crop improvement. Genetic transformation and marker assisted selection open enormous opportunities to full fill the challenges related to food production and nutritional balance.
Approximately 20 disease resistant genes have been isolated from a wide range of plant species in last decade. Resistant genes against various Phyto-pathological elements such as bacteria’s, fungi, nematodes as well as viruses have been isolated and mapped using molecular markers and we can use these markers in confirmation of gene transfer. In this way we can obtain new verities of improved resistance.
Similarly insect resistant genes have also been mapped from various plants. Some of the genes show a perfect insecticidal effect and several genes have been widely used in development of insect resistant transgenic cotton, rice and maize. Another approach has been used in which breeders used such genes encodes endo-toxins of Bacillus thuringiensis (BT) which have a valuable potential in the way of insect resistance.
A biotic factor like soil salinity, acidity and drought are some of the most important agriculture threats that cause yield losses in all major field crops. There are many quantitative trait loci (QTL’s) have been studied for drought and acidity resistance but there is still a need of discovering a major loci which help to develop tolerant varieties.
Biotechnology also offers improvement of nutritional quality for example the poor eating and cooking quality rice are mostly high yielding. The cooking and eating quality of cereal crops i.e. rice is dependent mainly on three traits. Amylase content, Gelatinization temperature and Gel consistency are controlled by waxy locus on chromosome 6. So, we can transform rice plants with the waxy gene through marker assisted selection. Another success story of genetic engineering is to increase Vita. A content in endosperm of rice helps in lowering malnutrition and balancing micronutrients in diets of poor farmers.
The most remarkable emphasis of present agriculture is yield. Biotechnology and genetic engineering use two different ways to increase yield. First one is by increasing harvest index through semi dwarf gene which reduces plant height. And the other one is utilization of Hetrosis. But still a reduced rate of increase in yield is observed. Through marker assisted technology now we are able to isolate genes responsible for high yield in wild species of field crops. And then transfer them in to cultivated varieties to develop transformed plants which are high yielding.
Actually there are many ways in biotechnology and genetic engineering to develop such varieties which contribute to sustainable food production. which are high yielding and of best quality as well as less dependent on chemicals and thus, environmental friendly which also help us to fight against the most lethal issue GLOBAL WARMING.
