春季气候多变,管好棉花营养钵苗床,是保全苗、育壮苗(苗茎红绿各半,茎叶无病斑,生长粗壮墩实。)、防“五苗”(高温烧苗、高脚旺苗和弱苗,受冷红茎到顶的小老苗、低温发病死苗。)的关键。 一、控好床温 苗床温度是保证全苗,实现壮苗,防止“五苗”的主要措施。一般下种后至齐苗,床温控制在30—35℃,有利于出苗,防止烂种烂芽。齐苗至一片真叶,床温控制在20—25℃;一片真叶至二片真叶,床温控制在20℃,防止高温烧苗、高脚旺苗和弱苗,有利于培育壮苗。 二、控好苗床湿度 苗床湿度,是育壮苗防低温发病死苗的重要措施。一般苗床齐苗后,苗床土壤含 Changeable spring climate, tube cotton seedling nutrition bed, is to protect the seedlings, nurturing seedlings (seedlings red and green halves, stems and leaves without disease spots, thick stout Dunzhuang.), “Five seedlings” (high temperature seedlings, High foot Wangmiao and weak seedlings, by the cold red stem to the top of the small seedlings, cold disease death seedlings.) The key. First, control bed temperature bed temperature is to ensure that the whole seedlings to achieve strong seedlings, to prevent the “five seedlings” of the main measures. Generally under the seedlings to Qi, bed temperature control at 30-35 ℃, is conducive to emergence, to prevent bad kinds of rotten buds. Qi Miao to a true leaf, bed temperature control at 20-25 ℃; a true leaf to two true leaves, bed temperature control at 20 ℃, to prevent high-temperature burning seedlings, tall seedlings and weak seedlings, is conducive to nurturing seedlings . Second, the control seedling bed humidity seedbed humidity, seedling is an important measure of anti-hypothermia seedlings. After the general seedbed Qi Miao, seedbed soil containing