Feeding a Hungry World

 Food and Agriculture Organization (FAO) of United Nations estimates 40 countries have large amount of food insufficient for their population. This account almost 1 out of 7 billion of total population of world. In one part of the world excessive food and obesity is becoming a serious problem day by day, in other part (developing and least developed countries) people are dying out of hunger. In contrary to this, human population is growing and mouths to feed has increased, at the same time, land to grow is becoming limited. It comes with a challenging situation to plant science to develop high yielding and disease/pest resistant crops.

A series of improvement in plant sciences has been found. Since the beginning of civilization and domestication of agricultural practices, selection of crops for better traits and high productivity continued. This was noticed clearly after Mendel’s work in nineteenth century. By then, selection was the established method for improvement in crop breeding. A good example here comes from Corn (Zea mays), which is a modern crop introduced from years long selection process of Teosinte (Zea Mexicana). Now corn is totally dependent on humans for survival. Selection is still a prominent and effective method of crop improvement in plant breeding.

Early part of twenty century in United States was a productive era in plant breeding science. This led to development of high yielding varieties, which need higher doses of fertilizers, pesticides, mechanization and irrigation. Transformation for these technologies continued to developing countries over past 40 years, which led to higher productivity in agriculture production system. This achievement is known as Green Revolution.

Dr. Norman Borlaug led green revolution was possible due to development of high-yield varieties. Development and extension of dwarf strain of wheat in Mexico (by CYMMIT) and rice in Philippines (IRRI).  At the same time disease-resistant varieties of crops which are able to stand against many bacteria, fungi, viruses and nematodes were developed.  It was a breakthrough in agricultural science, the benefit of this spread away to Asia and Africa too. Countries like India, Pakistan and china were benefited largely by this.

Green revolution was not a miracle without high rate of input supply. Thus, there came some problems, mostly in developing countries. Critics blame green revolution as a costlier technique and environmentally not safe. More on this, genetic diversity of the plants are also eroded. As there needed high dose of pesticides and fertilizer, adequate irrigation and high mechanization, developing part of the world suffered from inadequacy. This lead to salinity in soil.

Solution to problem led by green revolution should start from the part of the world where population is very high. Development in improved irrigation system, organic fertilizers, biological control of pest and diseases may reduce the negative impact of green revolution by a large part.

Erosion of genetic diversity starts from monoculture practices. Monoculture is growing the same crop year after year in a large region. Not only crop, this has narrowed down to some selected varieties of crops only. For example, half of the wheat acreage in the United States is planted with just nine varieties of wheat.  Sustainable agriculture on other hand consist of mixture of annual and perennial crops, which can be harvested for a number of years without replanting.

As traditional varieties ( land races) are abandoned and replaced with modern , high yielding varieties and as habitat destruction brings about the extinction of wild relatives, valuable genetic heritage is lost forever, which is known as genetic erosion. This erosion can be reduced by gene or seed banks. In U.S. seed bank is located at National Centre for Genetic Resources Preservation in Fort Collins, Colorado under USDA in 1958. More than 500,000 seed samples representing 8,000 species are housed there.  Liquid nitrogen under at very low temperature is used as preservative. Heirloom varieties or traditional varieties are encouraged to cultivate for their preservation.

Germplasm is the encoded information of a plant, the genetic instructions that dictate not only the type of the plant but also all the traits unique to an individual plant. Germplasm is the center of an international controversy, the question of ownership.   In June 2004, the international Treaty of Plant Genetic Resources for Food and Agriculture was enacted to protect valuable genetic resources. Ratified by 55 nations, the treaty defines plant genetic resources as “any genetic material of plant origin of actual or potential value for food and agriculture.”

FAO has identified some of the potential alternative crops. Alternative crops can be brought to the attention of global agriculture and can be diversify the world’s food sources. Quinoa is one of them, which is found in South America.  Grain amaranth is another new world crop under development for world market.   A South America legume called Tarwi has been taken in interest in recent days.  Similarly Tamarillo and naranjilla two relatives of tomatoes are also identified as good alternative to vegetables supply. Tamarillo is tree tomato. Oca is a tuber crop as of wheat potato, which is from Andes.

Biotechnology is use of living organism to provide products for humanity. Cell and tissue culture is one of the established biotechnology technique where whole plant is developed from a single cells. Small pieces of plant tissues are grown in a nutrient medium supplemented with plant hormones, after a few days, the cells begin dividing and produce a small, undifferentiated mass of tissue known as a callus.  Similarly molecular plant breeding technique uses marker assisted selection process for identification and incorporation of some special traits that are not identifiable through phenotype.

The genetic engineering, especially the recombinant DNA technology is a new and major changing technology in field of plant breeding.   While traditional methods of plant breeding allows the transfer of useful genes within a species or closely related species, genetic engineering  allows the transfer of useful genes from one organism to a totally unrelated plant species. Organism with foreign gene are called transgenic.  The development of transgenic plants begins with the identification and isolation of the useful trait containing gene and useful vector to transfer that. Use of Plasmids or gene gun shoot can be done for gene transfer.

Genetic engineering has two major traits developed in plants. First one is herbicide resistance.   Bacterial gene that confers resistance to the herbicide glyphosate has been introduced in many plants.  However there are lot of cases where farmers are against the developer of these kind of traits. In 2002, Monsanto a seed company which developed herbicide resistant wheat variety was objected by farmers. Country like Japan and South Korea objected those wheat crops containing herbicide resistant. Insect resistance is another trait that is developed in crops through genetic engineering. Bacillus thuringiensis (Bt) a common soil bacterium is used for insect resistance trait.

There is widespread adoption of Bt corn, as it is resistant to European corn borer. A study in 1990 at Cornell University charged the Bt corn for harming monarch butterfly population. There are subsequent studies, which proves that fining was not correct. However, this controversy is still there. The genetic engineered golden rice which contains Beta Carotene (converts into Vitamin A) is being developed as a new tool to eradicate malnutrition problem.  Later Bill and Melinda Gates Foundation has funded for addition of vitamin E, more protein and enhanced iron and zinc availability in same rice variety.

There are many crops beyond staple food which are genetically engineered like soybean, alfalfa, tomato, and canola. New traits like disease resistance is being developed in genetically engineered crops.  Genetic engineering being used to produce rice plants resistant to a devastating disease called leaf blight, caused by the bacterium Xanthomonas oryzae.

The scope of biotechnology extends beyond food crops. One of the promising use is in pharmaceuticals to produce many vaccines and medicines. Also, since 1990s, there are a lot of ongoing greenhouse and field trials of GM trees in 16 countries. In 2010 USDA approved for eucalyptus tree.

There are many issues with GM crops. Issue on regulation is one of them. In 1992 Food and Drug Administration (FDA) developed a policy on GE crops, recommending that “developers consults with FDA about bio-engineering foods under development”.  If the FDA feels that GM variety is not safe for marketing comparing with other non GM food, by testing 120 days before that food is marketed, there would be ban on marketing. Environmental Protection Agency (EPA) evaluates any possible effects on non-target organism. The U.S. Department of Agriculture (USDA) monitors the field crops that are genetically engineered.

Critics argue that GM crops are seriously affecting our environment, can harm human health and benefits only large agribusiness conglomerates. GM crops are questioned all over the world. Zambia refused US food aid in 2002 with fear of GM. European countries were more cautious, however, recent days they started to grow GM crops. There is concerns over transfer of herbicide resistant gees from GM crops to other related species. Also, natural development resistant in weeds are also questioned.  Use of terminator gene is also questioned seriously in developing nations, so that same seed cannot be planted and has to depend on seed companies year after year. So there is also blame for super insect development and killer weeds development having developed the resistance against GM. Though there are any issues against GM, the National Research Council in 2010 resealed a report saying on impact of GM crops in American farmers. The report has found economic and environmental benefits rather than harm.

In conclusion, there are questions against use of Biotechnology. However, biotechnology is found useful in many ways. It is  needed to feed the growing population which signifies there would be further development in biotechnology in days to come.