论文部分内容阅读
油松育苗重茬年限愈多,松苗长势愈壮。为什么呢?原来油松苗是靠依附在根上的一种菌根菌,增加根系的吸收面积。这种菌根菌和松苗营着一种共生关系。在这种关系中菌根菌自土壤中取得矿物质特别是磷和水分输给根部所吸收,根菌所得的报酬是自根组织中收到碳水化合物或者其它营养物。这种菌根菌积累愈多,就愈能增加根系吸收面积,即根系的发育,松苗生长也就愈旺盛。实践证明,多年重茬,菌根菌积累就愈多,松苗就愈壮。松苗愈壮,亦就愈能积累更多的菌根菌。但是,油松茬改种其它作物,如刺槐、芥菜、白菜等后,积累的菌根菌就遭到破坏。肥沃的熟地由于菌类较多,首次育油松苗,会使菌根菌的形成受到抑制,使幼苗生育不良。
Pinus tabulaeformis cropping more years, pine seedlings grow stronger. Why? The original pine saplings rely on the roots attached to a mycorrhizal fungi, increasing the absorption of the root area. This mycorrhizal fungus and pine camp with a symbiotic relationship. In this relationship, mycorrhizal fungi take in minerals, especially phosphorus and water, from the soil and transport it to the roots. The remuneration for root bacteria is the receipt of carbohydrates or other nutrients from root tissue. The more accumulation of mycorrhizal bacteria, the more can increase the root absorption area, that is, the development of the root system, pine seedling growth will also be more prosperous. Practice has proved that for many years stubble, the more mycorrhizal bacteria accumulated, the stronger the pine seedlings. SONG Miao more strong, it will be able to accumulate more mycorrhizal bacteria. However, the accumulation of mycorrhizal fungi on oilseed stubble crops has been destroyed after being re-cultivated on other crops such as locust, mustard and cabbage. Fertile Rehmannia due to more fungi, the first oil pine seedlings, the formation of mycorrhizal bacteria will be inhibited, so that poor seedling growth.