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落叶松是针叶速生用材树种之一,它具有生长迅速、适应性强、材质优良用途广等优点。随着义务植树群众运动的开展,落叶松的育苗任务越来越大,因此,掌握苗期生长规律,进行科学育苗,以达到优质高产的目的,具有重要意义。落叶松苗期,从播种到秋季防寒,大体可分为四个阶段: 一、出苗期:从播种到幼苗出土,种壳脱落,这阶段大约经过10～15天,主要特点是种胚吸水后开始萌动,胚根下扎,由于胚轴伸长把子叶和种壳带出地表,开始向下弯曲,接受光照后,种壳脱落,子叶展开。主要抚育措施是:此时幼苗比较嫩弱,易失水和遭受冻害,
Larch is one of the fast-growing timber species, it has the advantages of rapid growth, strong adaptability, good material use and so on. With the voluntary tree planting movement, larch seedling growing task, therefore, to master the law of seedling growth, scientific nursery, in order to achieve the purpose of high quality and high yield, of great significance. Larix seedlings, from sowing to autumn cold, can be divided into four stages: First, the seedling stage: from sowing to seedling excavated, the seedling shed, this stage after about 10 to 15 days, the main feature is the germ start after absorbing water Sprouting, the radicle under the bar, due to hypocotyl elongation of the cotyledons and seedlings out of the surface, began to bend down, after receiving light, the seed coat shedding, cotyledons unfold. The main tending measures are: At this time more tender and tender young seedlings, easy to lose water and suffered frost damage,