大量元素缺乏对樟树幼苗生长的影响

Effects of nutrient deficiency on the growth of Cinnamomum camphora seedlings

为探讨不同营养元素缺乏对樟树幼苗生长的影响,以樟树当年生幼苗为材料,设置全素、缺N、缺P、缺K、缺Mg 5个处理,观测其营养缺乏症状及生长状况。结果表明:樟树幼苗缺N时症状出现较早,表现最为明显,其叶片偏小、变黄绿色,整株矮小,长势较弱,其次为缺Mg,而缺P和缺K幼苗症状出现缓慢,表现相对不明显。不同缺素处理的樟树幼苗的苗高、地径、各组织生物量、主根长、侧根数量和叶面积均显著低于全素处理(P<0.05),其中缺N影响最大,其次为缺Mg处理。缺素处理增加了幼苗叶生物量比,降低了根生物量比和根冠比,其中缺Mg对根系生长影响最大。因此,N和Mg是限制樟树幼苗生长的主要影响因子,在樟树苗期营养管理中,应及时施用N肥,并保证Mg、P和K肥的供应。

To study the effects of nutrient deficiency on the growth of Cinnamomum camphora seedlings,5 treatments including total nutrient,N deficiency,P deficiency,K deficiency and Mg deficiency were set up to observe the deficiency symptoms and growth status of one-year-old seedlings.The results showed that the symptoms of N deficiency appeared earlier and obvious,their leaves were small and yellow green,the whole plant was short and the growth was weak,followed by Mg deficiency,while the symptoms of P and K deficiency seedlings appeared slowly and the performance was not obvious.The height,ground diameter,tissue biomass,main root length,lateral root number and leaf area of seedlings under different nutrient deficiency treatments were significantly lower than those under total nutrient treatments(P<0.05),among which N deficiency had the greatest effect,followed by Mg deficiency.Deficiency treatment increased leaf biomass ratio,decreased root biomass ratio and root shoot ratio,among which Mg deficiency had the greatest effect on root growth.Therefore,N and Mg are the main factors limiting the growth of camphor seedlings.In the nutrition management of camphor seedlings,N fertilizer should be applied in time,and the supply of Mg,P and K fertilizer should be ensured.