2.16 Effects of Common scab on potatoes
Common scab affects the quality and marketability of the tuber but does not have a significant effect on the attained yield (Slack., 1992 ;Hao et al., 2009). However some researchers have reported that the disease can also result in yield losses (Chater, 2006). Common scab can have a more negative effect on farmers who produce potato seed as these are condemned by certification agencies. When the incidence of seed tubers infected is 3% to 5% the seed is rejected (Verma and Sharma, 1992) and there is also an increase of peeling costs (Wale et al, 2008) in the case of ware potatoes.
Post- harvest yield losses are higher in infected tubers as the shelf life is reduced (Zadeb et a l.,2008). Some authors have mentioned that when infected tubers are marketed locally they could still fetch their normal price but problems arise when the potatoes are to be exported and the washing processes will make the tubers more visibly unsightly and therefore difficult to market.
2.17 Control measures for common scab
The management of common scab is very problematic and there has been no effective control method hitherto (Dees et al., 2013).There are however some methods that have been shown to lessen the effects of this disease. Common scab can be controlled by the use of certified seed, use of seed dressers such as pentachloronitrobenzene(PCNB) or mancozeb dust (Agrios ,2005). However freshly cut tubers can be affected by high concentrations of mancozeb (Pung and Cross S, 1999)
Potato monoculture should be avoided to reduce inoculum and crop residues should be destroyed after harvest .Common scab thrives in dry soil conditions, application of adequate water from tuber formation to about 6-8 weeks can greatly ...
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...ato Council. Ref: R248.
Slack, S. A., 1992. A look at potato leaf-roll virus and PVY: past, present and future. Valley Potato Grower 57, 35-39.
Shi, Q. H., and Z. J. Zhu., 2008. Effects of exogenous salicylic acid on manganese toxicity, element contents and anti-oxidative system in cucumber. Environmental and experimental botany 63: 317–326.
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Suzuki, H., 1940. On the relationship between rice susceptibility and penetration into host plants.
Serratia marcescens, a Gram-negative bacillus, was originally and solely considered a biological marker in the medicinal industry, due to its highly natural red pigment: Prodigiosin (Hejazi and Falkiner, 1997). The pigment has numerous roles within bacteria, which can be further translated into the pharmaceutical and medical domain. This bacterium naturally occurs in water, soil, on plants as well as in humans and animals (Khanafari et al, 2006), where it is deemed an opportunistic pathogen.
The appeal to monoculture is its simplicity. Only growing one crop means the growing conditions, maintenance, and harvesting will always be the same, so the process can be standardized. In terms of potatoes, Pollan looks at monoculture through the lens of farmers growing potatoes for McDonalds (Pollan 143). McDonalds requires a specific type of potato that will yield a large size for their French fries, and they need that potato to constantly meet their customers’ demand for French fries. A farmer seeking to be a supplier for them would not have the time and energy to cultivate other crops, making monoculture a lucrative option for him or her. This makes monoculture a product of the economical world around us. As Pollan states, the practice of monoculture goes against the way nature works. As seen in the 1800s, relying on a single crop makes that crop vulnerable to disease, insects, competing plants, etc. One farmer he interviews says that “the bugs are always going to be smarter than we are,” which begs the larger question Pollan is attempting to answer: are we in control of nature or is nature in control of us (Pollan 144)? The Irish’s attempt to control the potato was met with a severe response from nature. This explains the creation and use of
These studies have helped to further the understanding of how legumes respond in elevated carbon dioxide. Researchers have determined that growth at elevated carbon dioxide concentrations stimulates photosynthesis and the increase of carbon to the plant. However this increase requires a higher nutrient supply to account for the increase in photosynthetic output. Based on these findings, legumes have a competitive advantage over nonleguminous plants when grown at elevated level of carbon dioxide. In natural settings however, nutrient availability greatly affects the response of these legumes (2). Legumes are dependent on their symbiotic relationship to nitrogen fixing bacteria, and this relationship and its response to elevated concentrations of carbon dioxide will continue to be studied for years.
Burpee, Lee, and Richard Latin. 2008. "Reassessment of Fungicide Synergism for Control of Dollar Spot." Plant Disease 92.4: 601-06.
"Unstoppable plant diseases" do not threaten our world. Crop pestilences are nothing new and have existed all-throughout the thousands of years that humans have grown their own food. In fact, ancient agrarians had it even harder than we do today because they were completely reliant upon rainfall, as they did not have advanced irrigation systems.
There were many arbitrary causes of the Irish potato famine, one of which was a fungus, Phytophthora infestans, which was accidentally transferred to Ireland from Mexico. Since the fungus was airborne it was virtually impossible to stop, and it wiped out almost all of Irelands potato crop in just a few years. Specifically, this fungus c...
Anthocyanins, flavanols, flavanones,secoiridoids, phenolic acids, stilbenes, coumarins, and isoflavones form a large class of polyphenols, which are phenolic compounds. This study, however, focuses on one category of these phenolic compounds: phenolic acids. These particular compounds have been classified into two groups, namely hydroxycinnamic acids and hydroxybenzoic acids. The most common hydroxybenzoic acids are protocatechuic acid and gallic acid, while hydroxycinnamic acids include ferulic acid, coumaric acid, caffeic acid, chlorogenic acid, and sinapic acid, (Nigdikar, Williams, Griffin, & Howard). Unlike hydroxycinnamic acids, hydroxybenzoic acids usually occur at very low levels in some black radish, red fruits, and onions, accounting for about 10 ppm on a fresh weight basis. Protocatechuic ac...
The issue written in this article is regarding the banning and lack of approval for blight-resistant potatoes in the european union. Late potato blight, a potato disease caused by the the eukaryotic microorganism phytophthora infestans, is a significant cause for loss of crop and yield by potato farmers. Looking back to the past, the blight was responsible for the catastrophic Irish Great Famine of the 1840s causing eradication of their main food source, potatoes. As a result of the blight, potatoes become rotten and unsafe for human consumption. Late potato blight today is still a serious issue because it has caused the loss of $5.9 billion dollars of potatoes worldwide annually.By engineering blight resistance into potatoes, scientists have hoped to increase the yield and productivity of potato crops affected by this devastating disease. However, the attempts of the scientists are met with strong resistance by anti-GMO activists and lobbying groups, who are intent on food as naturally pure as possible. In consequence of not using genetically modified potatoes, the farmers are forced to use costly pesticides in an attempt to control the blight. With the human population rapidly increasing, it is essential that all measures be taken to increase food/crop yield in order to prevent starvation and hunger caused by the overpopulation. The battle between agricultural researchers like Simplot and the anti-GMO lobbying group GeneWatch is a controversial one that must be addressed by this generation and future generations.
In conclusion, this potato affecting disease, Phytophthora Infestins, resulted in killing over a million people in Ireland. In the time, the Irish relied heavily upon the potato crop. This devastating even greatly impacted the people through starvation, migration, and loss of land. The climatic change led to the end of the Phytophthora Infestins affecting the potato crop. The future generation diversified their food sources as a valuable lesson.
Size of potato-will be the same as it will be cut using a cork and borer which cuts them all to the same diameter.
...o Ireland, but this only hurt them worse. Potatoes are very nutritious, and the transition of corn which lacked the nutrients caused scurvy. But in the end the British assumed if they just kept buying from the Irish they would pay their rents and buy some of their food from Britain. (History)
Potatoes have become a staple to the diet of humans.They have become so popular since they come in a variety of shapes, sizes, and tastes. They are also cheap and easy to grow, and they taste delicious! Potatoes have changed the course of history in several ways. Who knew that potatoes, just a starchy vegetable, could have helped shape the world in so many ways. First, the Irish Potato Famine killed a million people and caused another million to move out of Ireland. Second, soldiers in the United States army were able to eat potatoes throughout the war. Third, they prevented a famine from occurring in England after there was not a sufficient amount of crops going to sustain the country's cries for food. Many people wonder if potatoes have
Domesticated potatoes were once all belong to one botanical species, Solanum tuberosum; it included thousands of varieties that had diversity in size, shape, color and other characteristics. The potato was first domesticated in the South America Andes, then the Puritans who took Mayflower arrived the land and the First Nations taught them about potatoes. Then the sailors went back to Europe and people started to plant potatoes in Spain, England, France, and many other countries in Europe. Later, potatoes were spread into Africa by the colonists. The crop was once believe to be poisonous by the local farmers who refused to plant them. However, the colonists persuaded the farmers and introduced potatoes as a low-price and high-production crop in substitute of wheat and rice.
...and to resist disease and pest include but are not limited to: tomatoes, potatoes, papaya, peas, and squash. (NERC 2005)
The potato tubes in higher concentration sugar solution will shrink