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线虫的生活史很简单,由卵孵化出幼虫,由幼虫脱皮变为成虫,雌雄虫交配,再产卵,这样完成生活史。雌虫产出的卵,在合适的条件下,不断发育,第一龄幼虫是在卵壳内发育的,脱一次皮变为二龄幼虫,从卵壳内孵化出来,遇到合适的寄主便开始侵入,所以,有人将二龄幼虫叫侵染幼虫。进入寄主后,二龄幼虫不断吸食发育,再脱一次皮变成三龄幼虫,这时,生殖器官开始发育,经第四次脱皮即变为成虫。雌虫与雄虫交配后产卵,雄虫交配后死去。有些根结线虫,没有或很少有雄虫,雌虫不经交配也能产卵繁殖(孤雌生殖)。在环境合适的情况下,线虫完成一代大约需一个月左右,温度低或其他条件不适宜,需要时间就长一些,许多线虫在一个生长季可以发生几代。但是,有些线虫,如小麦粒线虫,一年只发生一代。
The life cycle of the nematode is very simple. The eggs hatch out of the larvae, become larvae from the larvae, mate with the male and the female, and then spawn. This completes the life history. Eggs produced by females, under appropriate conditions, continue to develop. The first instar larvae develop within the egg shell and become detached to the second instar larvae and hatch from within the egg shell and encounter a suitable host Began to invade, so someone called the second instar larvae infestation. Into the host, the second instar larvae continue to take advantage of development, and then off the skin into a third instar larvae, then, reproductive organs begin to develop, the fourth peeling into adults. Female and male mating spawn, males die after mating. Some root-knot nematodes, with few or no males, and females can spawn without mating (parthenogenesis). When the environment is right, it takes about a month for the nematodes to be completed and the temperature is low or otherwise unfavorable, requiring longer periods of time. Many nematodes can occur for several generations in a single growing season. However, some nematodes, such as wheat nematodes, only occur one generation per year.