What is the history of potato blight?
The fungus found on the potatoes was first described and named by Dr. C. Montagne, a French physician in Napoleon's army. He shared his observations with Rev. M. J. Berkeley, in England, who recognized that this new fungus was probably connected with the blighting in some way.
What caused the Potato Famine of 1852?
Early blight, caused by Alternaria solani, is also often called "potato blight". Late blight was a major culprit in the 1840s European, the 1845 - 1852 Irish, and the 1846 Highland potato famines.
What is late blight and how is it treated?
Late blight is a notorious disease that is often associated with the Irish Potato Famine, yet even today it remains a destructive disease. It causes fruit rot and plant death on tomatoes and potatoes. Due to its ability to travel long distances and destroy entire fields, growers need to know how to diagnose and manage the disease.
What happened to the potato crop in 1846?
Food was in short supply the first winter, leaving fewer seed potatoes to be planted the next season. The summer of 1846 brought new hope as the plants began green and healthy, but the blight came again and destroyed any hope of a better winter. Help from England was slow to come.
When was potato blight discovered?
The potato blight that caused all of this death and destruction had actually been detected on U.S. shores in 1843, two years before it showed up in Europe, wrote study leader Jean Ristaino, a plant pathologist at NC State.
Who discovered the potato leaf blight?
Discovered by John Niederhauser in the 1950s, in the Toluca Valley in Central Mexico, while working for the Rockefeller Foundation's Mexican Agriculture Program. Published in Niederhauser 1956.
When was late blight discovered?
The disease was first discovered in the United States in the early 1840s where it caused devastation to many crop yields. Late blight is also responsible for causing the Irish potato famine in 1845. Phytophythora infestans is an oomycete pathogen.
Who is the one of mycologist involved with late blight of potato?
Spontaneous generation and disease causation: Anton de Bary's experiments with Phytophthora infestans and late blight of potato. J Hist Biol. Fall 2010;43(3):459-91.
Why it is called late blight of potato?
Late blight caused by the fungus Phytophthora infestans is the most important disease of potato that can result into crop failures in a short period if appropriate control measures are not adopted.
How did potato late blight start?
Late Blight is caused by the fungus Phytophthora infestans. The late blight fungus is especially adapted for growth under conditions where water is present and cool temperatures persist.
Why is Phytophthora infestans famous?
Phytophthora infestans is a destructive plant pathogen best known for causing the disease that triggered the Irish potato famine and remains the most costly potato pathogen to manage worldwide.
Why is it called early blight?
Early blight of potato is caused by the fungal pathogen Alternaria solani. The disease affects leaves, stems and tubers and can reduce yield, tuber size, storability of tubers, quality of fresh-market and processing tubers and marketability of the crop.
Who is father of mycology?
Heinrich Anton de BaryHeinrich Anton de Bary, (born Jan. 26, 1831, Frankfurt am Main [Germany]—died Jan. 19, 1888, Strassburg, Ger. [now Strasbourg, Fr.]), German botanist whose researches into the roles of fungi and other agents in causing plant diseases earned him distinction as a founder of modern mycology and plant pathology.
Who is father of Indian mycology?
E.J. ButlerThe father of mycology is P.A. Micheli, and the father of Indian mycology is E.J. Butler.
Who first discovered fungi?
The medical relevance of fungi was discovered in 1928, when Scottish bacteriologist Alexander Fleming noticed the green mold Penicillium notatum growing in a culture dish of Staphylococcus bacteria.
How did the potato blight get to Ireland?
The cause was actually an airborne fungus (phytophthora infestans) originally transported in the holds of ships traveling from North America to England. Winds from southern England carried the fungus to the countryside around Dublin.
Was the potato famine England's fault?
In fact, the most glaring cause of the famine was not a plant disease, but England's long-running political hegemony over Ireland. The English conquered Ireland, several times, and took ownership of vast agricultural territory. Large chunks of land were given to Englishmen.
How was the potato famine solved?
The "famine" ended in 1849, when British troops stopped removing the food. While enough food to sustain 18 million people was being removed from Ireland, its population was reduced by more than 2.5 million, to 6.5 million.
How many Irish died during the potato famine?
1 million deathsIt decimated Ireland's population, which stood at about 8.5 million on the eve of the Famine. It is estimated that the Famine caused about 1 million deaths between 1845 and 1851 either from starvation or hunger-related disease. A further 1 million Irish people emigrated.
What causes potato blight?
Early blight of potato is caused by the fungus, Alternaria solani, which can cause disease in potato, tomato, other members of the potato family, and some mustards. This disease, also known as target spot, rarely affects young, vigorously growing plants. It is found on older leaves first. Early blight is favored by warm temperatures and high humidity.
How to prevent blight on potatoes?
In general, late maturing varieties are more resistant than the earlier maturing varieties. Keep plants healthy; stressed plants are more predisposed to early blight. Avoid overhead irrigation. Do not dig tubers until they are fully mature in order to prevent damage. Do not use a field for potatoes that was used for potatoes or tomatoes the previous year. Keep this year’s field at least 225 to 450 yards away from last year’s field. Surround the field with wheat to keep wind-blown spores from entering. Use adequate nitrogen levels and low phosphorus levels to reduce disease severity. See current recommendations for chemical control measures.
What is the disease of potato?
Late blight of potato is a serious disease caused by Phytophthora infestans . It affects potato, tomato and, occasionally, eggplant and other members of the potato family. Late blight is the worst potato disease. It was first reported in the 1830s in Europe and in the US. It is famous for being the cause of the 1840s Irish Potato Famine, when a million people starved and a million and a half people emigrated. Late blight continued to be a devastating problem until the 1880s when the first fungicide was discovered. In recent years, it has reemerged as a problem. It is favored by cool, moist weather and can kill plants within two weeks if conditions are right.
What is the white fluffy growth on the bottom of the leaves?
Disease Identification. White, fluffy fungal growth is present on the bottoms of leaves in moist weather. Leaf spots are not bordered by veins.
How to tell if a leaf is dying?
Symptoms. Spots begin as small, dark, dry, papery flecks, which grow to become brown-black, circular-to-oval areas. The spots are often bordered by veins that make them angular. The spots usually have a target appearance, caused by concentric rings of raised and depressed dead tissue. A yellowish or greenish-yellow ring is often seen bordering the growing spots. As the spots become very large, they often cause the entire leaf to become yellow and die. This is especially true on the lower leaves, where spots usually occur first and can be very abundant. The dead leaves do not usually fall off. Dark brown to black spots can occur on stems.
How to tell if a plant has a leaf spot?
The spots often have pale green to yellow rings surrounding them. The spots are not bordered by veins but can grow across them. In cool, moist weather, the spots grow rapidly into large brown to purplish black areas. The disease may kill entire leaflets or grow down the petioles and into the stem, killing the plant above it. When the weather is moist, a white fungal growth appears on the edges of the dead areas, usually on the undersides of the leaves. In the field, plants often give off a distinctive fetid or decaying odor.
What causes late blight?
Late blight is caused by the water mold Phytophthora infestans. The pathogen reproduces asexually in the United States. These asexual spores cannot overwinter without plant tissue, so the main sources of inoculum are contaminated plant debris/tubers that were improperly disposed, volunteer plants growing from infected tubers, transplants, and compost piles. However, once an outbreak occurs the pathogen can rapidly infect surrounding fields.
What is the disease that causes tomato rot?
Late blight is a notorious disease that is often associated with the Irish Potato Famine, yet even today it remains a destructive disease. It causes fruit rot and plant death on tomatoes and potatoes. Due to its ability to travel long distances and destroy entire fields, growers need to know how to diagnose and manage the disease.
Can Phytophthora infestans be found on tomato plants?
Phytophthora infestans infections produce characteristic symptoms that can form on the leaves and/or stems of tomato and potato plants. Both plants display similar symptoms which consist of dark lesions surrounded by white sporulation or ‘fuzz’ under humid/damp conditions but may appear just as dry dark lesions under dry conditions. Therefore, to diagnose late blight under dry conditions, place the infected sample (i.e. leaf) in a damp zip-lock bag for a day to see if white sporulation appears.
What is late blight?
Late blight is a serious fungal disease of potatoes. It is worldwide in its distribution. It occurs in potato growing areas of the world. Winter is the main potato growing season in India. It is followed by hot summer months in the plains. The drought and high temperature kill the fungus in the soil. ADVERTISEMENTS:
Why are potatoes free from blight?
The crops grown in the plains have been usually free from the epidemics of late blight because the chief predisposing factors (temperature and moisture) that render potato plants susceptible to disease are absent during the period of their growth. The temperature is high for the development of the disease.
Why are my potatoes getting brownish?
They get separate infections while in the hill. There is brownish discoloration of the skin of those parts of the tub ers which lie nearest the surface of the soil.
Where is late blight epidemic?
The late blight epidemics are thus rare in the plains in India. It is destructive to the crop grown in the rainy season. The disease occurs annually in the cooler Himalayan regions extending from Assam to Kashmir at an altitude of 6,000 ft. or more as the crop is grown in the rainy season.
When does blight appear on a plant?
Symptoms of Late Blight: The disease first appears on the tops of the plants generally after the blossoming period but mostly in the month of January. It may appear as well at any time during the growth period of the plant. The conditioning factor is the favourable environment.
Who confirmed De Bary's observation?
Melhus (1915) confirmed De Bary’s observation. De Bruyn (1926) opined that the fungus overwinters in the soil but this remains unconfirmed. Kaung (1956) stated that in the temperate regions the fungus perannates in soil in the form of sporangia and germ tubes.
Is Phytophthora infestans a causal organism?
The causal organism is Phytophthora infestans (Mont.) De Bary. The mycelium is aseptate conenocytic, hyaline and branched. The hyphae are both intercellular and intracellular.
Overview
Life cycle, signs and symptoms
The asexual life cycle of Phytophthora infestans is characterized by alternating phases of hyphal growth, sporulation, sporangia germination (either through zoospore release or direct germination, i.e. germ tube emergence from the sporangium), and the re-establishment of hyphal growth. There is also a sexual cycle, which occurs when isolates of opposite mating type (A1 and A2, see § …
Etymology
The genus name Phytophthora comes from the Greek φυτό–(phyto), meaning : "plant" – plus the Greek φθορά (phthora), meaning : "decay, ruin, perish". The species name infestans is the present participle of the Latin verb infestare, meaning : "attacking, destroying", from which we get the word "to infest". The name Phytophthora infestans was coined in 1876 by the German mycologist Heinrich Anton de Bary (1831–1888).
Physiology
Melatonin in P. infestans/host systems reduces the oomycete's tolerance to stress. PiINF1 is the INF1 in P. infestans. Hosts respond with autophagy upon detection of this elicitor, Liu et al. 2005 finding this to be the only alternative to mass hypersensitivity leading to mass programmed cell death.
Genetics
P. infestans is diploid, with about 11–13 chromosomes, and in 2009 scientists completed the sequencing of its genome. The genome was found to be considerably larger (240 Mbp) than that of most other Phytophthora species whose genomes have been sequenced; Phytophthora sojae has a 95 Mbp genome and Phytophthora ramorum had a 65 Mbp genome. About 18,000 genes were detected within the P. infestans genome. It also contained a diverse variety of transposons and …
Origin and diversity of P. infestans
The highlands of central Mexico are considered by many to be the center of origin of P. infestans, although others have proposed its origin to be in the Andes, which is also the origin of potatoes. A recent study evaluated these two alternate hypotheses and found conclusive support for central Mexico being the center of origin. Support for Mexico comes from multiple observations includi…
Disease management
P. infestans is still a difficult disease to control. There are many chemical options in agriculture for the control of damage to the foliage as well as the fruit (for tomatoes) and the tuber (for potatoes). A few of the most common foliar-applied fungicides are Ridomil, a Gavel/SuperTin tank mix, and Previcur Flex. All of the aforementioned fungicides need to be tank mixed with a broad-spectru…
Historical impact
The effect of Phytophthora infestans in Ireland in 1845–52 was one of the factors which caused over one million to starve to death and forced another two million to emigrate from affected countries. Most commonly referenced is the Great Irish Famine, during the late 1840s, from which the Irish population has still not fully recouped. The first recorded instances of the disease were in the …