. Canadian journal of agricultural science. Agricultural Institute of Canada; Agriculture. Green Apple Bugs Attacked by a Fungous disease (Photo by L. G. Saunders). life-history is known. The most of the last class are supposed to belong- to the second group ,the aseus-bear- ing fungi, but are placed temporarily in the Fungi Im- perfec'ti luitil more is known of ascigerous -tagc, without wjiich knowledge they eannot be ela-sified. Life History of a Typical Entomophthora. Infection anicmg rungi results, in must cases, from contact with a conidial spore which, adher- ing
. Canadian journal of agricultural science. Agricultural Institute of Canada; Agriculture. Green Apple Bugs Attacked by a Fungous disease (Photo by L. G. Saunders). life-history is known. The most of the last class are supposed to belong- to the second group ,the aseus-bear- ing fungi, but are placed temporarily in the Fungi Im- perfec'ti luitil more is known of ascigerous -tagc, without wjiich knowledge they eannot be ela-sified. Life History of a Typical Entomophthora. Infection anicmg rungi results, in must cases, from contact with a conidial spore which, adher- ing to the insect host, enters its body means of a ger- minating hypha or tube. Although this process has never yet been actually seen, it is generally supposed that the hypha penetrates the insect's body at some point where the integument is less highly developed, as, for instance, between the body segments or joints of the legs or perhaps throngb the stigmata. It has also been proven that in some cases infection re- sults when the spores are taken directly into the stomach with the food, but this method is not so com- mon as the one firsit mentioned. After the hypha of germination has entered the host it grows and develops at the expense, first of the softer tissues but latei- of those parts more highly chitinized. Many authors think that fungi have the power of. secreting some li((uid wliich acts on the body tissues of the host and helps to break them down and convert them into food for the developing plant. This is prob- ably a fact, for it could onlj^ be through the agency of such a digesting secretion that the fungus would be able to break down the harder tissues as it does. In growing, the fungus does not usually form a threadlike, branched mycelium, but multiplies by means of what is known as hyphal bodies. Those hy- |)lial bodies are .short, thick fragments of the plant: of varying size and shape, which grow by means of bud- ding, and in many cases look in&l
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