Xu Yulan, Zhang Yuemin, Li Yunfei, Li Genqian, Liu Daiyi, Zhao Minchong, Cai Nianhui
College of Biological Science, Technology of Beijing Forestry University, Beijing 100083, China.
Key laboratory for Forest Resources Conservation and Use in the Southwest Mountains of China, College of Forestry, Southwest Forestry University, Kunming 650224, China.
Int J Mol Sci. 2012;13(5):6507-6520. doi: 10.3390/ijms13056507. Epub 2012 May 24.
A field experiment was conducted using a 3 × 3 orthogonal regression design to explore the growth promotion of one-year-old Yunnan pine seedlings (Pinus yunnanensis Franch.) in response to foliar application of IAA (indole-3-acetic acid) at rates of 0, 200 and 400 mg·L(-1) and IBA (indole-3-butyric acid) at rates of 0, 200 and 400 mg·L(-1) in order to promote the growth during the seedlings' early stage. The experiment was conducted at the Lufeng Village Forest Farm of Yiliang County in Kunming, Yunnan, China. The results showed that IAA and IBA were effective in growth promotion of Yunnan pine seedlings. The response of both growth increment and biomass accumulation to the concentration of IAA and IBA can be modeled using a bivariate surface response, and each growth index had a peak value. Growth indexes increased with the increase of the dosage of photohormones before reaching a peak value, and then decreased. The different growth indexes had various responses to the concentrations and ratio of IAA and IBA. The foliar application of IAA in combination with IBA showed the largest improvement on the biomass of the needles, followed by stems and roots. The higher ratio of IAA promoted stem diameter growth, root system development and biomass accumulation in the needles, while a higher ratio of IBA contributed to height growth and biomass accumulation in the stem. Based on the auxin effect equations on the different growth indexes and surface response, the optimum concentrations and the (IAA:IBA) ratios can be obtained. The optimum concentrations of IAA and IBA were 167 and 186, 310 and 217, 193 and 159, 191 and 221, and 206 and 186 mg·L(-1), with corresponding ratios of 1:1.11, 1:0.70, 1:0.82, 1:1.15 and 1:0.90, respectively, at the maximum seedling height and collar diameter growth as well as biomass accumulation at the root, stem and needle. The above growth indexes were 22.00%, 79.80%, 48.65%, 82.20% and 107.00% higher than the control treatment.
采用3×3正交回归设计进行田间试验，以探究叶面喷施浓度为0、200和400 mg·L⁻¹的吲哚-3-乙酸（IAA）以及浓度为0、200和400 mg·L⁻¹的吲哚-3-丁酸（IBA）对一年生云南松（Pinus yunnanensis Franch.）幼苗生长的促进作用，从而促进幼苗早期生长。试验在中国云南昆明宜良县禄丰村林场进行。结果表明，IAA和IBA对云南松幼苗生长有促进作用。生长增量和生物量积累对IAA和IBA浓度的响应可用二元表面响应模型进行模拟，且各生长指标均有一个峰值。生长指标在达到峰值前随光激素用量的增加而增加，之后下降。不同生长指标对IAA和IBA的浓度及比例有不同响应。叶面喷施IAA与IBA组合对针叶生物量的促进作用最大，其次是茎和根。较高比例的IAA促进茎直径生长、根系发育和针叶生物量积累，而较高比例的IBA有助于苗高生长和茎生物量积累。根据生长素对不同生长指标的效应方程和表面响应，可得出最佳浓度和（IAA∶IBA）比例。在幼苗最大苗高、地径生长以及根、茎、叶生物量积累方面，IAA和IBA的最佳浓度分别为167和186、310和217、193和159、191和221、206和186 mg·L⁻¹，相应比例分别为1∶1.11、1∶0.70、1∶0.82、1∶1.15和1∶0.90。上述生长指标分别比对照处理高22.00%、79.80%、48.65%、82.20%和107.00%。
