油松容器苗和裸根苗生长与造林效果对秋季施肥的响应

【目的】探究不同秋季施肥处理条件下油松容器苗和裸根苗苗期生长、养分积累和造林效果的差异，为生产上培育油松良种壮苗提供理论基础和技术支持。【方法】以大田培育的当年生油松播种容器苗和裸根苗为研究对象，设置0(对照)、12、24、36 mg/株4种秋季施肥水平，于90%以上苗木形成顶芽后进行施肥处理，并于翌年进行雨季造林试验。测定造林前的苗高、地径、生物量、根冠比、养分含量及造林后苗木成活率和苗高、地径相对生长量等指标，分析出圃苗木性状与造林效果之间的相关性。【结果】秋季施肥24 mg/株处理下的油松容器苗苗高、地径、生物量、氮、磷、钾含量均表现最佳，该处理下容器苗整株生物量、氮、磷、钾含量较对照分别增加了41.8%、31.4%、65.6%和48.8%;油松裸根苗受秋季施肥影响较小。容器苗氮含量在各器官中的分布从大到小表现为根>叶>茎，裸根苗氮含量在各器官中的分布从大到小表现为叶>根>茎；磷、钾含量在容器苗和裸根苗各器官中的分布从大到小均表现为叶>根>茎。雨季造林试验结果显示，油松造林效果受苗木类型影响显著，容器苗造林当年和第2年春季的苗高、地径相对生长量...

Responses of growth and afforestation performance of Pinus tabuliformis container and bareroot seedlings to fall fertilization

【Objective】 The aims of this research were to examine the responses of container and bareroot Pinus tabuliformis seedlings to nursery fall fertilization supplements and assess their subsequent two-year field performance. This study was conducted to provide a theoretical basis and technical support for the cultivation of high-quality P. tabuliformis seedlings. 【Method】 Fall fertilization was applied when the terminal bud ratio reached 90% of the total seedlings. P. tabuliformis container seedlings and bareroot seedlings were supplied with fertigation (i.e., irrigation with soluble fertilizer) at 0 (control), 12, 24, and 36 mg/plant. The effects of fall fertilization on growth and afforestation performance were then tracked and analyzed over two-year using the following cirteria seedling height, root-collar diameter(RCD) and nutrient content, etc. 【Result】 The height, RCD, biomass, N content, P content and K content of container seedlings with 24 mg/plant were higher than those of the other doses. In addition, the total biomass, N content, P content and K content were significantly increased by 41.8%, 31.4%, 65.6% and 48.8%, respectively, compared to those of the control seedlings, whereas the bareroot seedlings were less affected by fall fertilization. The distribution of N content in the organs of container seedlings was root > needle > stem, whereas that in the bareroot seedlings was needle>root>stem. The distribution of P and K contents in the organs of container and bareroot seedlings exhibited the same order: needle>root>stem. The results of the rainy season afforestation test showed that the rate of afforestration was significantly affected by the seedling type. Compared with the bareroot seedlings, the relative growth in the height and RCD of container seedlings were significantly higher in the first year of outplanting and the following spring, and the survival rate of container seedlings in the following spring was similar to the pattern observed for the relative RCD. The relative growth in height in the second year spring was significantly affected by fall fertilization, and fall fertilization at 24 mg/plant yielded the highest value. The afforestation survival rate, relative growth of height, and RCD of seedlings were closely related to seedling root biomass, root shoot ratio, root N content, root P content, root K content and stem P content in the initial stage of afforestation. 【Conclusion】 Fall fertilization at 24 mg/plant was best for optimizing the morphological growth and nutrient accumulation of P. tabuliformis container seedlings. The survival rate and growth of 1-year-old P. tabuliformis container seedlings were significantly greater than those of the bareroot seedlings.