There are several essential factors that contribute to the quality of life society enjoys today. One of these factors is the ability to produce crops such as corn, soybeans, wheat, cotton, and several others. On occasion these crops experience stressors. These stressors can be from abiotic or biotic factors. Biotic stressors mainly include insect herbivores, whereas abiotic stressor mainly include temperature and water or lack thereof. It is vital to understand how crop react to these stressor in order to predict and possibly contradict the effect on the crops. When dealing with insect herbivores the outcome can be devastating. Insects can destroy large amounts of crops. To prevent insects from destroying crop, insecticides are used as well as transgenic crops are used. Abiotic factors such as drought can be more difficult. The total amount of semi-arid land on earth is one-third, and the rest of the land experiences unexpected drought occasionally (Fang and Xiong, 2015). This means that nearly all the crops in the world are at risk of experiencing some kind of water shortage. Due to these abiotic and biotic stressors, and extensive amount of research has been conducted and is still being conducted to minimize the negative effects. In the following sections will be an overview of the abiotic and biotic factors along with the crops response to each, as well as the genetic mechanisms studied to improve a crops ability to cope with these stressors.
Crops response to drought
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Genetically modified crops have become increasingly popular in the last few decades. Despite the fact that they are a controversial topic: we see GMOs as a growing technology that if regulated and tested will have great benefits when it comes to conserving water. One of the ways they are modifying genes is to make the plant more drought tolerant and take less water to germinate. In addition, to produce a better yield while practicing dry land farming and controlled irrigation water conservation. There are studies trying to modify the plants so that they can increase the rate of photosynthesis and depth of root structure. Scientists are also trying to decrease the rate of water loss through transpiration. “Corn, the crop with the highest global production, annually sustains losses on the order of 15 percent of potential yield attributable to drought. As the climate changes as a consequence of global warming, some climates will become more arid, increasing drought and resulting in up to 10 million more lost tons of maize per year. It has been estimated that 25 percent of these losses may be resolved by genetically modifying maize to be more drought tolerant.” (Clive.
In contrast, the counter argument claims that GMOs are unsafe for human consumption. However, GMOs actually improve human health by reducing the amount of pesticides needed for successful crop production. With the use of GMOs in crop production, the amount of pesticide and herbicide application has decreased. To resume, successful crop production is essential to a farmer’s success, which could be why over 18 million farmers throughout the world utilize GMOs. The successful production of crops can be achieved by genetically modifying crops with resistance against insects, weeds, and other threats. Resistance to different stressors has reduced pesticide applications by 8.1 percent. Additionally, crops that are modified to be resistant to specific
Genetically modified crops are being developed to produce their own pesticide. This will bring the rapid appearance of resistant insects. Even worse, these pesticide producing plants have killed some beneficial insects and pests that many farmers use in their crops. For example, inserting a gene from a snowdrop, a perennial herb found in Europe and Asia into a potato, made the potato resistant to the green fly, but killed lady bugs that feed on green flies.
Primarily, genetically engineered crops result in countless long-term, detrimental impacts on the environment. As the United States becomes increasingly dependent on such crops for a majority of its food supply, these harmful environmental impacts are becoming evident. Many GMO crops are modified to be herbicide-resistant, such as the Roundup Ready crop, which allows farmers to spray herbicides without causing damage to the plants. While the ridding of weeds increases the level of production for these farmers, their total elimination greatly interferes with the natural interdependency of the ecosystem. One impacted species includes the Monarch butterfly, as its population decline has been directly linked to the use of genetically engineered crops. The weeds being eliminated include the
There are concerns that the introduction of GM crops in developing countries might lead to a reduction in biodiversity, particularly in areas where a crop originated and a wide range of natural genetic variation is found. There might also be unexpected consequences of gene transfer (between plants, for example an uncontrollable ‘escape’ of genes into neighbouring wild plants by pollen. There are also concerns that pests or weeds could acquire resistance to crops. Therefore their effectiveness is questioned and would probably hinder the development process,
Although many may disagree, there are many advantages to genetic modification in foods. Environmentally speaking, Crops that have inherited pest resistance through genetic alterations often reduce the need for the application of chemical pesticides. Chemical pesticides can often have harmful effects on the environment. They can kill beneficial insect species in the field and get into other ecosystems when washed into waterways. In addition, genetic engineering can be used in many ways to improve the efficiency of crops. Resistance to herbicide and insect pests are two ways can help to improve productivity. With the improvement of productivity comes the reduction of cost. The use of GMOs can reduce the need for the application of chemicals. In some cases they may lead to traits which ease planting, harvesting, or processing in ways which reduce the cost of production.
Although genetically modified foods do produce favorable effects on biodiversity, it can also harm it a great deal. The use of the genetically modified crops with herbicide properties, pose threats not only to the target pest but also to non pest insects and key pollinators. For instance, major pollinators and other harmless species are being poisoned by neonicotinoids, a chemical found in genetically modified seeds. However, according to Paul and Cummins, not only are bee populations declining, but also birds, butterflies and fish. The decline in these species raises quite the alarm due to the fact that without them, we may not be able to grow food. Bees are essential in growing crops due to the fact that crops need to be pollinated in order to germinate. For this reason, the high number of crops containing the neonicotinoids are causing the crucial pollinators to spontaneously perish.
There are many natural thing damaging our crops a few examples are tillage which is exposing the soil, erosion which is removing minerals. America can prevent this by using less- tillage techniques to reduce erosion ("Crop Farming." Funk & Wagnalls New World Encyclopedia, ) Crops face many problems one of them being bugs. Farmers find it fairly easy to use chemicals to kill these bugs but these chemicals can have damaging effects. Such as
There are a multitude of studies addressing concerns about pesticide control methods such as genetically engineering Bt maize and its role in pest control. Beyond embedded chemicals, there are also concerns with external pesticide use and the stress that it puts on native pollinators. Herbicide resistance presents a different potential problem in the form of destroying a native habitat for the pollinators. Finally another issue that arose was the vast growth of agricultural land use and human expansion contributing to climate change and loss of habitat for monarchs and other
Due to cotton previously being attacked by pest that caused immense damage, the main purpose for GM cotton was to create a more pest resistant form of crop. This was achieved by inserting a foreign gene into the cotton seed from bacillus thuringiensis, the introduced gene is mainly targeting cottons most common pest; bollworm. With the new line of cotton, research has found that farmers are actually resorting to less chemical usage on their crops due to the pesticide with the cotton keeping the insects almost under control, with the help of 1-2 chemical coverings as opposed to the traditional 8.
Any severe environmental stress such as drought and global warming can trigger unpredictable changes to engineered crops. It is this combination of unpredictability and ignorance that led Dr. Barry Commoner, one of our nation's most eminent biologists, to conclude:
Most public concern has been focused on human health and safety regarding the use and consumption of these foods, but potential environmental impacts are important to consider as well. Many varieties of genetically engineered crops are intended to decrease the need for chemical pesticides and fertilizers, but the scope of environmental impacts does not stop at chemical usage. Common concerns about GM crops include the effects of cross-pollination, so-called “genetic contamination,” and the escape of GM crops from cultivation and their interactions with native species. Conversely, the environmental benefits of GM crops range from reducing dependence on chemical pesticides to the ability to treat polluted soils with bioremediating plants (Ford, 2004).
A transgenic crop is a crop that is created by artificially transplanting genes from another unrelated plant or from a completely different species. The amount of transgenic crops has increased greater than thirty fold between 1996 and 2001. Close to seventy percent of the world's corn produced is grown in the United States. And of that corn that is grown in the United States, about thirty percent is transgenic corn (ISAAA 2001). This is an appropriate response to our success in controlling Lepidopterans on Bt-corn versus unmodified corn. In conventional spraying of chemical insecticides at appropriate times, first generation larvae are usually sixty to ninety-five percent effective and forty to eighty percent effective in the second generation larvae. The efficacy of Bt-corn can be incredibly positive compared with non-Bt versions as illustrated in Figure
Genetically Modified insect resistant crops produce the toxic substances as a results it effect non-target organism and entire ecosystem. Biodiversity has significant role to balance environment as biodiversity decreases interaction between species decrease and ecosystem and food chain affect adversely. Some weeds are source of food for