Dependence of Asian honeybee on deciduous woody plants for pollen resource during spring to mid‐summer in northern Japan

Apis cerana japonica Radoszkowski, endemic to Japan, is known to be one of the most important pollinators for wild plants and crops, such as buckwheat, in cool to warm temperate Japan. To determine the degree of dependence of A. cerana japonica on forest resources, we analyzed pollen brought back to nests in a typical “Satoyama” landscape with relatively high deciduous forest coverage in northern Japan. We divided the landscape elements of the study area into three types: deciduous forest, conifer plantation and open land according to landcover digital data, and each pollen taxon was assigned to one of these three types of landscape elements. We collected total pollen loads of 15.75 g (total of colonies A and B) in May (spring), 1.57 g (total of colonies A and C) in June (early summer), 19.03 g (total of colonies A, B and C) in July (mid‐summer) and 45.61 g (total of colonies A, B and D) in September (autumn). Deciduous forests are the most important foraging habitats for A. cerana japonica in the “Satoyama” landscape especially from spring to mid‐summer when mass flowering of tall trees and shrubs species provides rich floral resources for developing bee colonies. On the other hand, the bees frequently foraged from herbaceous plant species in autumn when flowering of tree species reduces and herbaceous plant species have flowering peaks. In turn, the bees provide pollination services to a number of wild flowers blooming in various forest layers ranging from the canopy to the understory layer.     

Isolation of Lectins by Affinity Chromatography with Porcine Plasma Proteins Immobilized on Agarose

To develop a convenient method to isolate lectins, we prepared an affinity gel by coupling plasma proteins with agarose beads under conditions where the pH did not exceed 7.5. The validity of the use of this affinity gel in combination with elution using a hapten saccharide was confirmed by isolation of concanavalin A from Jack bean meal. Successful application of the method was demonstrated by isolation of two novel vegetable lectins from udo (Aralia cordate) and wasabi (Wasabia japonica). The method would be useful to isolate new lectins from various sources including plant and animal tissues.     

缙云山不同生境蝴蝶花(Iris japonica Thumb.)分株种群格局及对草本多样性的影响

运用空间格局、生态位及多样性分析,探讨了重庆缙云山自然保护区林缘旷地(OAFE)、竹林(BF)及常绿阔叶林(EBF)3类生境蝴蝶花(Iris japonica Thumb.)自然种群分株格局特征及对草本多样性的影响机制.结果表明:方差均值比(V/m)和Moristia指数(Iδ)的格局判别分析表明,3类生境中蝴蝶花分株种群从0.5 m×0.5 m至2 m×2 m尺度均为聚集分布;从林缘旷地-竹林-常绿阔叶林,种群分株密度逐渐降低,总体格局规模与格局强度(PI)在各尺度均呈下降趋势.林缘旷地与竹林生境中,蝴蝶花的分布,降低了原优势种的优势度,并显著降低草本层物种多样性(p<0.05),但在常绿阔叶林生境中对原优势种的优势度及草本物种多样性的影响很小.不同生境中蝴蝶花种群格局对草本多样性的影响机制各不相同:林缘旷地生境,通过强的更新生态位(地上空间与根生态位)与营养生态位(获取水分与养分资源)竞争,降低草本物种丰富度尤其是偶见种丰富度;竹林生境,通过更新生态位(根生态位)与营养生态位(获取光与养分资源)竞争,降低了草本偶见种丰富度;常绿阔叶林生境,物种间生态位重叠较低,表现一定的资源竞争,但对草本多样性影响很小.林冠决定蝴蝶花分株种群格局强度、克隆生长的强弱及林下土壤状况,从而影响蝴蝶花与草本层其它物种之间生态位竞争的强弱是决定蝴蝶花种群对草本层物种多样性影响机制的重要因素.     

Anatomy and ultrastructure of epidermal cells in the haustorium of a parasitic flowering plant,Cuscuta japonica, during attachment to the host

Changes of epidermal cells in the haustorium of the parasiticCuscuta japonica during its attachment to the host plantimpatiens balsamina were studied with light and electron microscopy. In the transverse sections of dodder stems not in contact with the host, epidermal cells had rounded outlines. However, when haustorial initials developed in the cortex of the parasite stem at the contact site, the epidermal cells had more dense cytoplasm and conspicuous nuclei than before, and their outline was flat in the longitudinal section. As meristem cells developed from those initials, the epidermal cells became more elongated. When the haustorium was fully matured, the apical tips of the elongated epidermal cells at the contact site branched like toes, producing numerous projections via cell wall invaginations. This event caused spaces to form between the projections; coincidently, the surface area of the apical ends of the epidermal cells increased. The dense cytoplasm at those projections contained prominent nuclei and abundant other organelles, suggesting a active metabolism. Osmiophilic particles, releasing into the cell walls from the cytoplasm, were though to be associated with the loosening and elongating of the epidermal cell walls. Dense and homogeneous materials were secreted within the spaces between the projections. These materials could play an important role in cementing the haustorium onto the surface of the host organ.     

蔓生百部的化学成分研究

从蔓生百部(Stemona japonica)根中分离得到13个化合物,通过波谱数据,它们鉴定为β-谷甾醇(1)、豆甾醇(2)、5,11-豆甾二烯-3β-醇(3)、苯甲酸(4)、4-甲氧基苯甲酸(5)、1,8-二羟基-3-甲基蒽醌(6)、1,8-二羟基-6-甲氧基-3-甲基蒽醌(7)、氧代狭叶百部碱(8)、百部定碱(9)、异狭叶百部碱(10)、绿原酸(11)、栀子苷(12)和藏红花素A(13).所有化合物均为首次从该植物中分离得到.     

辽河流域栽培稻对二化螟(Chilo suppressalis)的抗性

采用活体成株鉴定法测定了辽河流域主栽水稻品种对二化螟发育和为害的影响，同时测定了不同品种的主要形态特性、硅细胞数量和主要生化特性，评价这些品种对二化螟的抗性、分析其发生的可能机制。盐丰47对二化螟幼虫表现出较好的抗性，在沈农265上二化螟幼虫体重最小。在所测定的特性中，螟害株率与不同品种倒二叶叶角的自然对数之间具有显著的正相关关系，与稻茎Si含量之间具有显著的负线性相关关系；二化螟幼虫体重只与不同品种稻茎直径之间具有显著的正线性相关关系．研究结果对水稻品种杭件利用和未来水稻抗件育种的意义。     

A New Acylated Anthocyanin from the Red Flowers of Camellia hongkongensis and Characterization of Anthocyanins in the Section Camellia Species

Twelve anthocyanins (1-12) were isolated from the red flowers of Camellia hongkongensis Seem. by chromatography using open columns. Their structures were elucidated on the basis of spectroscopic analyses, that is, proton-nuclear magnetic resonance, carbon 13-nuclear magnetic resonance, heteronuclear multiple quantum correlation, heteronuclear multiple bond correlation, high resolution electrospray ionization mass and ultraviolet visible spectroscopies. Out of these anthocyanins, a novel acylated anthocyanin, cyanidin 3-O-(6-O-(Z)-p-coumaroyl)-β-galactopyranoside (6), two known acylated anthocyanins, cyanidin 3-O-(6-O-(E)-p-coumaroyl)-β-galactopyranoside (7) and cyanidin 3-O-(6-O-(E)-caffeoyl)-β-galactopyranoside (8), and three known delphinidin glycosides (10-12) were for the first time isolated from the genus Camellia. Furthermore, pigment components in C. japonica L., C. chekiangoleosa Hu and C. semiserrata Chi were studied.The results indicated that the distribution of anthocyanins was differed among these species. Delphinidin glycoside was only detected in the flowers of C. hongkongensis, which is a special and important species in the section Camellia. Based on the characterization of anthocyanins in the section Camellia species, there is a close relationship among these species,and C. hongkongensis might be an important parent for creating new cultivars with bluish flower color.     

Pyrophosphate-dependent phosphofructokinase from pollen: properties and possible roles in sugar metabolism

To evaluate the role of pyrophosphate-dependent phosphofructokinase (PFP. EC 2.7.1.90) in the sugar metabolism of pollen. its occurrence and properties were studied in pollen grains of several plants including camellia ( Camellia japonica L.). In all pollen samples, PFP was strongly activated by fructose-2,6-bisphosphate (F2,6BP), and the activity of F2,6BP-activated PFP was higher than that of phosphofructokinase (PFK. EC 2.7.1.11). PFP partially purified from camellia pollen required Mg²⁺ for activity with an optimum at 1 m M . and was almost unaflected by a variety of metabolites at 1 m M . Its molecular mass was around 220 kDa, and apparent K_m values for F6P, PP_i. F1, 6BP and P_i were 294, 4, 20 and 580 u M , respectively. The levels of F2.6BP. PP_i and F6P in camellia pollen were sufficent to support the forward reaction by PFP, and PFP, was 20- to 40-fold more active than PFK during pollen growth. These results suggest that pollen PFP plays a role in glycolysis but not gluconeogenesis. and the possible relevance of this to pollen tube growth is discussed.     

基于COⅠ基因探讨北京及其周边地区跳钩虾种群遗传结构

跳钩虾Platorchestia japonica栖息于湖泊、河流岸边,是重要的环境指示生物。本研究以线粒体COⅠ基因片段为分子标记,对北京及其周边地区22个采样点的128个样本进行种群遗传多样性和遗传结构研究。结果显示,623 bp的COⅠ基因序列中有567个保守位点、56个变异位点和38个简约信息位点。128个样本检测到43个单倍型,单倍型多样性为0.938,核苷酸多样性为0.011 72。最大似然法和贝叶斯法构建的系统发育树以及单倍型网络图表明,研究区域跳钩虾没有明显的地理种群结构,但所有单倍型形成2个遗传进化支。分子变异分析结果证实,跳钩虾2个进化支间的遗传变异显著高于进化支内的,进化支间固定系数为0.852 19,表明2个进化支遗传分化明显。本研究为进一步研究中国区域跳钩虾的遗传结构提供了有意义的基础数据。