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施肥与作物抗旱性有着密切的关系,对土壤肥力和氮﹑磷﹑钾三大营养元素与作物抗旱性关系的研究证明:旱地施肥后,满足了作物对营养元素的需求,促进了作物生长,增强了生理活动,通过渗透、水分、气孔、光合调节等生理生化机制影响作物的代谢活性。水分胁迫条件下施肥使叶片水势增强,束缚水含量增高,根系生长增强,作物吸水增强,气孔导度降低,水分散失减少,对作物水分生理及形态建设影响显著,提高了作物的抗旱性。不同营养元素与抗旱性的关系是不同的:如氮的抗旱作用随土壤干旱程度的加剧而降低,随着氮用量的增加甚至出现负效应;受到水分胁迫时,增施磷肥对植物的抗旱性一直表现为良好的正效应,而且在严重干旱时效果更加明显;因此,随干旱程度的加剧应适当增加磷肥的施用量。营养元素间配合施用有利于提高作物的抗旱能力。
Fertilization and crop drought resistance are closely related to the soil fertility and nitrogen, phosphorus and potassium three major nutrients and the relationship between crop drought research shows that: dry land fertilization, the crops to meet the nutritional needs of the elements and promote crop growth, Enhances the physiological activities and affects the metabolic activity of the crops through physiological and biochemical mechanisms such as infiltration, moisture, stomata and photosynthetic regulation. Under water stress, the water potential increased, the irreducible water content increased, the growth of root system increased, the water absorption of crops increased, the stomatal conductance decreased, and the water loss decreased, which had a significant effect on crop hydropathic and morphological construction and increased the drought resistance of crops. The relationship between different nutrient elements and drought resistance is different. For example, the drought resistance of nitrogen decreases with the intensification of soil drought and even negative effects with the increase of nitrogen use. When water stress is applied, It has been shown to be a good positive effect and more pronounced in severe drought; therefore, the application of phosphate fertilizer should be increased appropriately as the degree of drought increases. Nutritional cooperation between the elements will help improve the ability of drought-resistant crops.