生长环境与株龄对凤丹当年生果枝的生物量分配的影响

生物量分配研究是了解作物产量形成机制的基础。凤丹是以杨山牡丹（Paeonia ostii）为原种形成的栽培类群，也是新型木本油料作物油用牡丹的主栽品种。该文通过比较凤丹主要产区6龄种群、以及安徽铜陵和上海地区的4、6、8龄种群的当年生果枝大小与生物量分配，探讨环境和株龄对小枝生长与繁殖的影响。结果表明，凤丹植株的果枝数量随株龄增大而上升，不同株龄植株的单个果枝大小和果枝内生物量分配没有明显差异，果枝水平上没有株龄效应，但整株水平上株龄效应明显；果枝大小及生物量各指标之间存在明显相关性，但相关性在种群间变化较大；不同种群的果枝大小及生物量分配差异明显，果枝生物量分配明显随纬度、降水和光辐射强度变化而变化；异速生长方程模拟显示，大部分种群的果枝繁殖与营养生物量或总生物量之间为等速生长关系（斜率=1），但种群间截距变化较大。这些结果表明栽培环境对凤丹果枝的生长与繁殖有显著效应。

Effects of Growth Environment and Tree Age on Biomass Allocation within Fruit Twigs of Fengdan(Paeonia ostii)

Biomass allocation is critical for understanding the yield formation of crops. Fengdan is the cultivated type originated from Paeonia ostii and the predominant variety of oil tree Paeonia that is newly cultivated as one of the oil tree crops in China. In order to examine the effects of growth environment and tree age on twig vegetative and reproductive growth, we compared the biomass characteristics of fruit twigs among eight 6-year-old Fengdan populations from different sites and that between 4, 6 and 8-year populations cultivated at Shanghai, and Tongling of Anhui Province. The number of fruit twigs increased with age increase, while there was no significant difference of twig growth and reproduction between different aged populations, indicating age effects existed at individual level but not twig level. There were significant correlations between the trait measurements, whereas, such correlations varied among populations. The body sizes and biomass allocations of fruit twigs were different among different populations, and the variations of biomass allocation associated with environmental variables. By allometric relationship modeling analysis, the fruit twigs from most of populations displayed constant biomass allocation between growth and reproduction functions(slope=1) with varied intercepts among populations. Therefore, the cultivation environment has significant effects on the growth and reproduction of Fengdan.