Environment
Crown Rot of wheat caused by Fusarium is a widespread disease. It was previous believed that Crown Rot is restricted in its geographical distribution. In the United States, the disease is most prevalent in the driest and warmest regions of the Pacific Northwest. However, recent investigations have suggested that the disease is found is most cereal producing regions of the world.
Local environmental conditions play a large role in the prevalence of F. pseudograminearm. This is particularly evident during late season when the crops are maturing. While both rainfall and temperature are important, studies have shown that rainfall plays a much larger role in the prevalence and severity of Crown Rot; although a weak temperature-disease correlation does exist. In the field survey of wheat crops in Australia, the maximum summer temperature in areas where P. seudograminerum was found to be as high as 31ºC. Under drought conditions, where warm and dry weather predominates, Crown Rot symptoms are intensified. This is largely due to the pathogen's ability to survive and thrive under these conditions. Laboratory studies suggest that P. seudograminerum grows best under dry (<-1Mpa) conditions. They further showed that while the pathogen grew fairly well in temperatures ranging from 5ºC to 30ºC, it does not grow well at 5ºC or 35º.
Read more about this topic: Fusarium Pseudograminearum
Famous quotes containing the word environment:
“If the Revolution has the right to destroy bridges and art monuments whenever necessary, it will stop still less from laying its hand on any tendency in art which, no matter how great its achievement in form, threatens to disintegrate the revolutionary environment or to arouse the internal forces of the Revolution, that is, the proletariat, the peasantry and the intelligentsia, to a hostile opposition to one another. Our standard is, clearly, political, imperative and intolerant.”
—Leon Trotsky (1879–1940)
“People between twenty and forty are not sympathetic. The child has the capacity to do but it can’t know. It only knows when it is no longer able to do—after forty. Between twenty and forty the will of the child to do gets stronger, more dangerous, but it has not begun to learn to know yet. Since his capacity to do is forced into channels of evil through environment and pressures, man is strong before he is moral. The world’s anguish is caused by people between twenty and forty.”
—William Faulkner (1897–1962)
“A positive learning climate in a school for young children is a composite of many things. It is an attitude that respects children. It is a place where children receive guidance and encouragement from the responsible adults around them. It is an environment where children can experiment and try out new ideas without fear of failure. It is an atmosphere that builds children’s self-confidence so they dare to take risks. It is an environment that nurtures a love of learning.”
—Carol B. Hillman (20th century)