Corn, cotton and potatoes are three of the many commercial crops targeted for bt insect resistance. Insect attack has become a serious agricultural problem responsible for reductions in crop productivity. There are following three important bases of insect. Second generation of insect resistant transgenic plants. Biotechnological approaches for the control of insect pests.
Bt gene from bacillus thuringiensis and ipt gene from agrobacterium tumefaciens 7. Techniques for evaluating insect resistance in crop plants. Insect pests exhibit a diverse array of geneticbased responses when interacting with crop systems. In this article we will discuss about the insect resistance in plants. To combat this, farmers have used a variety of approaches, including the use of pesticides.
Although bt toxin is a remarkable protein by providing protection to the several economically important plants from insects challenge. It was discovered by ishiwaki in 1901 in diseased silkworms. Insect resistance in plants genetics biology discussion. We understand very little of the mechanisms used by insects to reject such invaders, and insect immunology really hardly yet exists as a discipline. Bacillus thuringiensis bt has been used as a main source for insect resistant genes. May 12, 2011 insectresistant transgenic crops were first commercialized in the mid1990s with the introduction of gm corn maize, potato and cotton plants expressing genes encoding the entomocidal. Relative to a susceptible plant, disease resistance is the reduction of pathogen growth on or in the plant and hence a reduction of disease, while the term disease tolerance describes plants that exhibit little disease damage. Pdf genetic transformation of crops for insect resistance. Economics of plant pollination flowering and fruiting of plants hybrid vigor in plants. Covers terminology and categories of resistance, and presents techniques for studying plant resistance. Insect resistant crops have become important tools for farmers, both large and small, around the world. Apr 12, 2016 pest resistance first reported in tobacco and tomato. With the advent of genetic engineering, genes for insect resistance now can be moved into.
Knowingly or unknowingly, ancient farmers selected for pest resistance genes in their crops, sometimes by actions as simple as collecting seed from only the highestyielding plants in their fields. Mcgregor, usda originally published 1976 the first and only virtual beekeeping book updated continously. Like other multicellular eukaryotes, insects constantly struggle against potentially pathogenic microorganisms. Insectresistant crop varieties suppress insect pest abundance or elevate the damage tolerance level of the plants. Resistance of plants is relative and is based on comparison with plants lacking the resistance characters, i. This article aims to provide a comprehensive catalogue of the insectresistance genes that have been transferred into crop plants. Without those pesticides, however, worldwide losses of crops to insect pests would be catastrophic. Biological basis of insect resistance in crop plants insect. Evolution of insect resistance threatens the continued success of transgenic crops producing bacillus thuringiensis bt toxins that kill pests. He gave three mechanisms of insect resistance in crop plants, viz.
Genetic engineering of plants for insect resistance. Plant genetic engineering technology offers the opportunity to develop insectresistant crops by the insertion and expression of genes showing resistance to insect pests. During plant domestication, some important features of plant resistance may be inadvertantly removed by the breeders, increasing their susceptibility. Approx 40 different genes conferring insect resistance have been obtained from microorganisms. First generation of transgenic insecticidal plants consist of. Based on evolutionary concept sympatric resistance.
Mineral nutrition contributes to plant disease and pest. Further research on bt by steinhaus 1951 lead to renewed interest in biopesticides and as a result, the more potent products such as thuricide a and dipela were. The full investigation of insect resistance in crop plants requires prolonged and coordinated study by entomologists, agronomists and geneticists which, of course, raises further problems of human relationships. Over the past halfcentury, insecticides have become the main weapon of choice against insect pests. Aspects of insect resistance in crop plants springerlink. Insect resistance management irm is said to be the key to sustainable use of the insecticide in both genetically modified crops and bt microbial spray formulations. With the emergence of biotechnology, the development of insect resistant plants by transferring the gene that produces the bt toxin became possible and this proce. The global scenario of crop damage inflicted by insects is a matter of serious concern. Genetic engineering of crops for insect resistance. Painter, reginald henry, 1901 insect resistance in crop plants. In rare cases, they can even ruin an entire fields produce by eating the crop or killing the plant itself. Pesticide resistance p genetically engineered ge crops. Retrospect and challenges article pdf available in turkish journal of agriculture and forestry 394.
Acquired by coevolution of plant and insect gene for gene. Importance of growing insect resistant crop in pest management programmes is discussed with reference to some of the major aspects of insect resistance in crop plants in tamil nadu and emphasis has been made in highlighting the fact that the plant resistance to insect should form the foundation upon which other components of the integrated pest management should be built. Insects attack all the crop plants and lead to considerable losses in yield as well as quality. Bt in corn confers resistance to european corn borers. Insect pests inflict damage to humans, farm animals and crops. Modern agriculture provides novel solutions to age old problems. This is a wellwritten, wellresearched book with good illustrations and a worthy successor to painters insect resistance in crop plants. Insectresistant crops through genetic engineering mu. In crop plants such as 1 reduction in plant growth or stunting. Other experiments are searching second and third generation insect resistant plants first generation transgenic plants. During sporulation, insecticidal protein crystals called bt toxins were produced by this grampositive. Current status of bt technology at the end of 2018, an estimated 23.
It results from insect plant coevolution and is crucial for their coexistence. Insectresistant crops generally produce compounds that are toxic to insects that attempt to eat the resistant plants. Insect resistance despite continuous plant breeding efforts, chemical control is the preferred management method for insect pests. Insect resistant crops through genetic engineering glenda d. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Insect resistance genes the insect resistance genes transferred into plants to date mainly target the insect digestive system.
Pdf insect attack has become a serious agricultural problem responsible for reductions in crop productivity. Environmental effects of insectresistant on gm crops. In 2010, 148 million ha of biotech crops were grown in 29 countries, representing 10%. Insectresistant crops through genetic engineering glenda d. Host plant resistance for insect control in some important crop plants. Insect pests have been defined by williams 1947 as any insect in the wrong place. If commercial crop varieties are selected as a source of donor, pure line selection, mass selection, or hybridization with elite germplasm is done for improvement. Byrne, colorado state university, professor, soil and crop sciences. Lecture 16 host plant resistance definition types and. The development of insectresistant crops is a major success in agriculture to reduce the use of pesticides, improve quality and yield, and decreases production costs. Bt irm is of great importance because of the threat insect resistance poses to the future use of bt plantincorporated protectants. Dec 09, 2008 to date, fieldevolved resistance to bt crops has been documented in only 3 insect species fig. Mar 24, 2014 an interesting new approach, not yet used with insect resistance genes, is the new plant vector system mat.
Each year billions of dollars are spent worldwide on insect control in agriculture 1. Some of the most damaging insect species belong to the lepidoptera, the second largest insect order comprised of moths and butterflies. The use of a crop plant with a single defense will pose as strong a selection pressure as the use of a single synthetic insecticide, since insect herbivores are. The donor source of resistance and the selection of certain progenies are two important factors of breeding methods to be considered while developing insect resistant plants. Insect resistant crops generally produce compounds that are toxic to insects that attempt to eat the resistant plants. For centuries, humans have searched for crop plants that can survive and produce in spite of insect pests. Despite this expenditure, up to 40% of a crop can be lost to insect damage, particularly in developing countries 2. One such nearterm biotechnology application is insect resistant crops through the insertion of a gene from bacillus thuringiensis bt that produces a protein toxic to certain insects of lepidoptera, coleoptera and diptera families. Bt toxin gene the source of the insecticidal toxins produced in commercial transgenic plants is the soil bacterium bacillus thuringiensis bt.
Transgenic crop plants must not be used until appropriate strategies for their use have been designed and not before crop plants with a variety of insect defenses have been developed. Pdf transgenic resistance to insects has been demonstrated in plants expressing insecticidal genes such as. The insect resistance action committee, a pesticide. Insect resistant corn and cotton have been credited with reducing the.
The dna sequences used usually encode proteins with insecticidal activity, so that in plants which contain introduced dna, an insecticidal protein is present. The second generation of crops aimed to improve the quality, often by altering the nutrient profile. Genetically engineering inherent crop resistance to insect pests offers the potential of a userfriendly, environmentfriendly and consumerfriendly method of crop protection to meet the demands of sustainable agriculture in the 21st century. Susceptibility increases as nutrient concentrations deviate from this optimum. Biological basis of insect resistance in crop plants.
Planteating insects can cause great damage to crops. Insectresistant crops through genetic engineering mu extension. The first crops provided are used for animal or human food and provide resistance to certain pests, diseases, environmental conditions, spoilage or chemical treatments e. Insect pollination of cultivated crop plants insect pollination of cultivated crop plants by s. The first transgenic crop plants showing insect resistance were grown commercially with modification of the cry gene isolated from b.
How have these crops contributed to sustainability. Genetic engineering of crops for insect resistance is the introduction of specific dna sequences into crop plants to enhance their resistance to insect pests. Resistancereduce fitness of insects after contact toleranceto stand and take it simply by outgrowing the damagecompensatory growth. Insect resistance in crop plants by painter, reginald and a great selection of related books, art and collectibles available now at. Pdf insect resistance to genetically modified crops. Resistance to insects in heterozygous crops such as maize is often quantitatively inherited so that effects of single resistance genes or factors are hard to identify.
This cycle is often called the pesticide treadmill as users spray more with increasingly potent chemicals and still lose ground. Genes for insect resistance from various sources 3. The extraordinary complexity of interrelationships between living organisms can nowhere be more manifest than in the field of applied entomology. In rice, biosynthesis of serotonin through the cytochrome p450 cyp71a1 gene increases the susceptibility of plants. Today, insect resistance transgenes can be introduced to plants.
The interaction between plants and disease organisms and pests is complex. Genetically modified crops are genetically modified plants that are used in agriculture. Bt cr op s we r e f i rs t pl a nt e d o n a l ar g e sc a le i n 1 9 96, w i th r ap i d a d op t io n le a d. Farmers use pesticides to kill these insects, but another way to reduce this yield loss is to produce plants that the insects cannot eat. Painter, reginald henry, 1901insect resistance in crop plants. Serotonin, a wellknown neurotransmitter in animals, is also produced by plants.
Research to transfer insect resistance genes from bt to crop plants is well under way. As a rule, plants with an optimal nutritional status have the higher resistance tolerance to pests and diseases compared to nutrient deficient plants. Webber office of biotechnology iowa state university north central regional publication where the story began for centuries, humans have searched for crop plants that can survive and produce in spite of insect pests. Insect resistant crop varieties suppress insect pest abundance or elevate the damage tolerance level of the plants. Mechanisms of insect resistance were first proposed by painter in 1951. Genetic engineering of crop plants for insect resistance a. Bioengineering of crop plants and resistant biotype.
So far, the efficacy of insect resistant crops through bt has been shown to be comparable to or better than the efficacy of current control methods. New genetic methods for insect control could substantially reduce expenditures, crop losses and be less detrimental to the environment. Examines the molecular biology and genetics of insect resistance in crop plants, and insect genes capable of. Genetically, engineering crop resistance to insect pests offer the potential of a user friendly environment and consumer friendly method of crop protection to meet the demands of sustainable agriculture in the 21st century. Pesticides are chemicals that will prevent pests from damaging the plants, either by killing the insect outright. More about how insect resistance can enhance sustainability pdf. Tolerance in crop plants to insect pests cambridge core. Induced defenses make the plants phenotypically plastic, and thereby, decrease the chances of the attacking insects to adapt to the induced chemicals. It also serves as a safeguard against the release of varieties which may be more susceptible than the existing ones. Genetic engineering of crop plants for insect resistance a critical. One reason is that fewer insecticide applications are required and in. Plant disease resistance protects plants from pathogens in two ways. Along with other evidence, the report by meihls et al. Each year, an estimated 25% of the food crop is destroyed by insects.
Insect resistance refers to crops that either naturally or through genetic engineering are able to resist insect damage. In the 1960s, concerns about their adverse health and environmental. Home december 1951 volume 72 issue 6 insect resistance in crop plants. Plant resistance to insects is a natural phenomenon based on plant selfdefense mechanisms.
Insectresistant biotech crops and their impacts on. Insect resistance held on an external server, and so may require additional authentication details croplife international fully acknowledges the source and authors of the publication as detailed above. In addition to bt endotoxins, various plant lectins and other nonbt genes from different sources have also been introduced in crop plants of economic importance. Resistance incorporated in a variety against different environmental stresses like insects, diseases, nematodes, heat, drought, cold, etc. Most have been derived from a single species of bacterium or a range of higher plants, although some insect resistance genes from animals and other microorganisms have also recently been introduced into crop plants. Introduction insect resistance management irm is the term used to describe practices aimed at reducing the potential for insect pests to become resistant to a pesticide. Depending on the structure of the ecosystem in a given area and mans view point, a certain insect might or might not be considered a pest. Insect eats plant plants make toxin 1 plants make toxin 2 plants make toxin 3 insect resistant to toxin1 insect resistant to toxin2. Genetic engineering of crop plants for insect resistance. Also gives consideration to potentially resistant material. Insect control is serious and greatest challenge for agricultural crops.
Mechanisms of plant defense against insect herbivores. Plant breeding for insect resistance like disease, insects are important causal factors of biotic stress in crop plants. Breeding for disease and insect resistance crops plant. The major aspects of insect resistance in crop plants and the achievements iii tamil nadu are discussed in this.
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