摘要
植物的展叶过程是由自身遗传因子决定的,同时又受到多种生态因子的调节。本研究旨在量化不同氮素指数施肥下楸树无性系叶片发育过程中各个参数变化情况,建立叶片生长模型和叶面积模型,分析不同氮素指数施肥与叶片发育的关系。2011年3—8月,在甘肃省天水市小陇山林科所选用2年生楸树无性系组培苗1~4,设置4种水平（CK、尿素6、10、14 g/株）指数施肥处理,记录整个施肥期间叶片叶长、叶宽、叶面积变化情况。结果表明：1）楸树无性系叶片参数变化呈＂S＂型曲线,叶片生长过程符合Logistic生长函数模型（P〈0.01）。不同氮素指数施肥对叶片参数6月份影响不显著,7和8月有显著影响（7、8月叶宽分别较CK增加了31.4%~38.7%和79.8%~111.2%,叶面积分别较CK增加了59.0%~98.8%和304.4%~423.0%,8月份叶长较CK增加了68.2%~92.3%）。7月份叶面积N14和N10处理无显著差异,8月份叶面积N10显著高于N6和N14,N14在生长后期氮素过量,最佳施氮量是10 g。2）通过分析logistic生长曲线得出：不同指数施肥延长了叶面积始盛期、盛末期、高峰期的到来,增加了7和8月最大积累速率,展叶持续天数受施氮影响较小。3）一元、二元、三元和幂函数都能够较好地拟合叶长、叶宽、叶长乘叶宽和叶面积的关系（R2均大于0.8）。拟合叶面积最好的指标是长乘宽,最好的拟合方式是幂函数（R2均大于0.95）。实践中可以直接测定叶长,用LA=63.801 4＋10.822 9L或是LA=0.108L2.45（R2均大于0.93）来进行指数施肥下楸树无性系不同发育阶段叶面积的预测。
Leaf expansion in plants is a process determined by both genetic and environmental factors. This research was aimed to quantify the variation in leaf parameters of Catalpa bungei clones under different nitrogen exponential fertilizations,establish leaf growth and leaf area models,and analyze the relationship between different nitrogen exponential fertilizations and response of foliage growth. Seedlings of four two years old C. bungei clones（ No. 1-4） by tissue culture were used as experiment materials. We set four urea dose levels of exponential fertilization,i. e.,control（ CK）,applying 6,10,and 14 g per plant,and then measured leaf length,leaf width and leaf area during the entire course of fertilization from March to August 2011 in Xiaolong Mountain Forestry Science and Technology Research Institute,Tianshui City of Gansu Province,northwestern China. Results showed that： 1） the change of leaf parameters presented an ＂S＂curve,and leaf development was in line with Logistic growth model（ P〈0. 01）. Different nitrogen treatments and CK showed consistent impacts on leaf development parameters in June,but varied in July and August（ compared with CK,leaf width increased by 31. 4%- 38. 7% in July and 79. 8%-111. 2% in August,leaf area increased by 59. 0%-98. 8% in July and 304. 4%-423. 0% in August,leaf area increased by 68. 2%- 92. 3% in August）. Leaf area in N10 and N14 treatments had no significant difference in July,but the leaf area of N10 was significantly greater than N14 and N6 in August. Nitrogen of N14 was excessive in the late growth period,and the optimum amount nitrogen was10 g. 2） Logistic growth curve showed that different exponential fertilizations postponed the arrival of initial growth peak period,the maximum growth peak period and the final growth period of leaf area,and increased the maximum growth rate in July and August, but little effect of different exponential fertilizations was found on foliage expansion days. 3） Univariate,binary and ternary regressions and power functions were all able to fit the relationship between leaf length,leaf width,as well as product of leaf length × width and leaf area（ R2〉0. 8）. The best fitting indicator of leaf area model was the product of length × width,and the best fitting method was power function（ for both R2 0. 95）. Leaf areas in the development stage for C. bungei clones under different nitrogen exponential fertilizations can be estimated by only measuring leaf length with the linear regression equation LA =- 63. 801 4 ＋10. 822 9L and power function regression equation LA = 0. 108L2. 45 in practice（ for both R2〉0. 93）.
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2015年第7期19-28,共10页
Journal of Beijing Forestry University
基金
"十二五"农村领域国家科技计划课题(2012BAD21B0304)
教育部博士点基金(20124404120008)
