Reproductive allocations and resource partitioning mechanisms in plants

本文研究了两种温带常绿半隐植物（Pachysandra terminalis和Coptis japonica）、两种落叶半隐植物（Allium vistorialis ssp.）和两种落叶半隐植物（Allium vistorialis ssp.）各组成器官中总氮、总可溶性氮、游离氨基酸等几种形态氮的季节变化、叶片叶绿素含量和光饱和光合速率。白头翁和赤藓属)和一种球茎多年生草本植物（Allium grayi）。两种常绿多年生植物的根状茎和根系中总氮浓度从冬季到春季都呈下降趋势，表明植物对春季新芽生长的利用程度较高。在根状茎中，从初夏到冬季，总可溶性蛋白质储存逐渐减少，同时游离氨基酸增加。氮主要集中在根系的游离氨基酸中，特别是在夏季。一年生叶片中总可溶性蛋白含量从春到夏呈下降趋势，冬季呈上升趋势。这种季节变化与先前研究中获得的光饱和光合速率的变化是一致的。叶绿素含量和叶绿素/总氮比值在夏季高于其他季节。结果表明，氮肥的利用方式较好地利用了夏季极弱的光和其他季节相对较高的光强。在整个季节中，各个器官的游离氨基酸库的主要成分是天冬酰胺。两种落叶林地多年生植物Allium victorialis ssp.各器官氮组分的季节变化。白桦和赤藓的光合速率变化也与光饱和速率的变化一致。在冬季和夏末，总可溶性蛋白和游离氨基酸含量均较高。值得注意的是，谷氨酰胺是这两种林地半隐植物冬季鳞茎中主要的游离氨基酸组分之一。另一方面，夏初至夏末，日本沙蚕的精氨酸和天冬酰胺含量最高。本文还对灰葱干物质分配的季节变化和碳氮经济性进行了分析。在这一原始多年生植物中发现了最独特的N组分和C/N比率的周转模式，这明显反映了该物种的栖息地条件非常不稳定和变化。少

Seasonal changes in several forms of nitrogen (total-N, total soluble-N, free amino acids) in various component organs, chlorophyll content and light-saturated photosynthetic rates of foliage leaves were investigated in two evergreen temperate woodland hemicryptophytes (Pachysandra terminalis and Coptis japonica), two deciduous hemicryptophytes (Allium vistorialis ssp. platyphyllum and Erythronium japonicum), and one bulbous perennial ruderal (Allium grayi). In two evergreen perennials, the concentration of total nitrogen in rhizomes and roots decreased from winter to spring, indicating the plant's utilization of new shoot growth in spring. In the rhizomes, total soluble protein stored by early summer decreased gradually until winter, coupled with an increase in free amino acids. Nitrogen was largely pooled in free amino acids in the roots, especially in summer. The content of total soluble protein in the current-year leaves decreased from spring to summer and then increased in winter. … More This seasonal change was coinncident with the change in light-saturated photosynthetic rates obtained in a previous study. In contrast, chlorophyll content and the ratio of chlorophyll to total nitrogen was higher in summer than in other seasons. The results indicate that nitrogen was used in a manner which better utilizes a very weak light in summer and the relatively high light intensities in other seasons. The major component of the free amino acid pool was asparagine in every organ throughout the season. Seasonal changes in nitrogenous fractions in various organs of two deciduous woodland perennials, Allium victorialis ssp. platyphyllum and Erythronium japonicum, were also coincident with the changes in light-saturated photosynthetic rates. High concentrations of total soluble protein and free amino acids were found in winter and also in late summer. It is also noteworthy that glutamine was one of the major free amino acid fractions in the bulbs of these two woodland hemicryptophytes in winter. On the other hand, arginine and asparagine were richest in early to late summer in E. japonicum and A. victorialis var. platyphyllum, respectively. Seasonal changes in dry matter allocation, and carbon-nitrogen economy of Allium grayi were also critically analyzed. Most unique turnover patterns of N-fractions and C/N ratios were discovered from this ruderal perennial, which obviously reflects a very unstable, changing conditions of the habitats of this species. Less