向日葵某些杂交种幼苗对缺铁的反应

RESPONSE OF SEEDLINGS TO IRON DEFICIENCY IN SOME SUNFLOWER HYBRIDS

铁(Fe)是植物必需的矿质元素之一,它不仅作为某些生理活性物质和某些酶的活性中心参与植物体内的氧化还原反应,而且作为必需的因子参与叶绿素的生物合成.但是,高等植物在利用铁时却有很大的差异.例如,在溶液培养条件下,单子叶植物利用铁的能力低于双子叶植物,而同种作物的不同品种或杂交种对铁的利用率也存在着一定的差异.根据文献报道,在缺铁条件下,无论单子叶植物或双子叶植物均能引起根部分泌有机酸,释放氢离子,致使营养液pH下降;在向日葵,缺铁时根尖发生某些形态变化和生理变化.通过各种试验。

Iron (Fe) is one of the essential mineral elements required by crops. Response of seedlings of three sunflower hybrids (NS-H-26-RM, NS-H-62-RM, NS-H-10) to iron deficiency were described. The experiments show that Fe- deficiency results in decreasing dry matter accumulation in seedlings (16～40%),pigment contents in chloroplast (chlorophyll is more than 80%, carotenoid is 60～70%) and pH value in nutrient solution, but the excretion of organic acids and amino acids in root increased significantly under the condition of Fe-deficiency in nutrient solution. Sensitivity of root system to Fe-deficiency is more evident than above-ground organs. Fe-deficiency resistance of NS-H-10 is higher than that of other two hybrids.