追施氮肥对浙江楠容器苗生长和 叶片养分状况的影响

以探讨实际生产中浙江楠1年生容器苗合理的追肥方法为目的,采用传统追肥和指数追肥两种方法,对容器苗生长和叶片养分状况进行了研究; 利用方差分析、多重比较等方法,对不同追肥方法和追加量处理的浙江楠1年生容器苗的生长、生物量积累和分配、根系形态、叶片养分含量和吸收量进行了分析。结果表明:采用指数追肥法的处理4、处理5和采用传统追肥法的处理2等3个处理的苗高分别达到24.50、22.80和22.15 cm,比未追肥的对照(处理1)增加了22.01%、13.92%和10.31%(P<0.05),且处理4的地径(3.74 mm)显著高于对照(3.36 mm)。传统追肥、指数追肥法处理的容器苗总干物质量均比对照有所提高,其中处理4高于对照30.85%,二者间差异显著; 根冠比在不同处理间差异不显著。不同的追肥措施均能促进主根和总根系增长,根系平均直径增粗,根系表面积和根系体积增大,且处理4与对照间差异显著。在采用指数追肥法的处理3、4和5中,随着追肥总量的增加,根系各形态指标表现出先升高后降低的趋势。叶片N、P和K含量在处理间差异不显著,但由于处理间干物质量差异显著,处理4和处理5的叶片对各营养元素吸收量显著高于对照。总体而言,采用指数追肥法追肥总量200 mg/株(处理4)较适宜,为浙江楠容器苗较好的追肥方式。

Effects of topdressing nitrogen on growth and nutrient status in leaves of Phoebe chekiangensis container seedlings

With the objective of discussing reasonable topdressing method for one-year-old container seedling of Phoebe chekiangensis under production condition, we used conventional and exponential topdressing regimes to study the growth and leaf nutrient status of seedlings. Variance analysis, multi-comparison were used to analyze the effects of different method and amount on the growth, yield and allocation of dry matter, root morphology, nutrient content and uptake in leaves of one-year-old container seedlings. The results showed that with seedling height 24.50, 22.80 and 22.15 cm respectively, treatment 4, 5 using exponential method and treatment 2 using conventional method were 22.01%, 13.92% and 10.31% greater than that of the control treatment(P<0.05). Moreover, the ground diameter of treatment 4(3.74 mm)was greater than that of the control treatment(3.36 mm)significantly. Contrast with control treatment, conventional and exponential topdressing treatment increased their yield of total dry matter. With the yield of treatment 4 30.85% higher than that of the control, significant difference was available between the two treatments. But significant difference was unavailable in root-shoot ratio among treatments. Conventional and exponential topdressing could promote main root length and root length, average diameter, surface area and volume of root. And significant difference was available in root morphology between treatment 4 and control. With the increasing of amount under exponential topdressing, root morphology of treatment 3, 4 and 5 showed a trend of initially increasing and then decreasing. Although significant difference was unavailable in nutrient content of leaves among treatments, the nutrient uptake of leaves of treatment 4, 5 was higher than that of control significantly as a result of significant difference in dry matter. In general, using exponential topdressing with the total amount 200 mg/seedling(treatment 4)was the topdressing method.