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81.
LÊDA REGIS 《Invertebrate reproduction & development.》2013,57(3):187-195
The number of eggs produced by Triatoma infestans is determined by the amount of blood ingested; the formation of one egg requires 16 mg blood. An exogenous supply of juvenile hormone, provided by the implantation of extra corpora aliata, increases egg production per unit of blood ingested. The corpus allatum is therefore implicated in the relationship between nutrition and fecundity. The rhythm of egg production is regulated by the nutritional state of the adult female: when the females are fed at frequent intervals, egg production becomes regular and continuous. This calls into question previous interpretations of egg-laying rhythms in the Triatominae as cyclic. 相似文献
82.
ANDREA FERREIRA DA COSTA PABLO JOSÉ FRANCISCO PENA RODRIGUES MARIA DAS GRAÇAS LAPA WANDERLEY 《Botanical journal of the Linnean Society. Linnean Society of London》2009,159(1):163-181
The species related to Vriesea paraibica (Bromeliaceae, Tillandsioideae) have controversial taxonomic limits. For several decades, this group has been identified in herbarium collections as V. × morreniana, an artificial hybrid that does not grow in natural habitats. The aim of this study was to assess the morphological variation in the V. paraibica complex through morphometric analyses of natural populations. Two sets of analyses were performed: the first involved six natural populations (G1) and the second was carried out on taxa that emerged from the first analysis, but using material from herbarium collections (G2). Univariate ANOVA was used, as well as discriminant analysis of 16 morphometric variables in G1 and 18 in G2. The results of the analyses of the two groups were similar and led to the selection of diagnostic traits of four species. Lengths of the lower and median floral bracts were significant for the separation of red and yellow floral bracts. Vriesea paraibica and V. interrogatoria have red bracts; these two species are differentiated by the widths of the lower and median portions of the inflorescence and by scape length. These structures are larger in the former and smaller in the latter. Of the species with yellow floral bracts, V. eltoniana is distinguished by longer leaf blades and scapes and V. flava is characterized by its shorter sepal lengths. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 163–181. 相似文献
83.
甘肃蝴蝶名录 总被引:1,自引:0,他引:1
基于近几年的野外工作,结合前人对甘肃省蝶类的研究,对甘肃省蝴蝶名录进行了整理,并对各分类阶元进行了统计。截至2013年,甘肃省共记录蝶类12科210属614种,科、属、种的数量分别占中国总数量的100%、57.22%和28.52%。按照中国动物地理区划,古北种285种,东洋种233种,广布种95种。甘肃省境内分布有各类珍稀濒危蝶类37种,其中国家Ⅱ级重点保护野生动物2种(凤蝶科的三尾凤蝶和绢蝶科的阿波罗绢蝶),列入《国家保护的有益的或者有重要经济、科学研究价值的野生动物名录》的有11属33种,列入《濒危野生动植物种国际贸易公约》的有4种,列入《世界濒危物种红色名录》的有5种。 相似文献
84.
85.
目的:基于钙黄绿素-铜(Ⅱ)荧光体系测定乙酰半胱氨酸。方法:在pH=8.0的Na2HPO.412H2O-KH2PO4缓冲液中,以492 nm为激发波长,520 nm为发射波长测定乙酰半胱氨酸溶液的荧光强度。结果:在pH=8.0的Na2HPO.412H2O-KH2PO4缓冲液中,二价铜离子与钙黄绿素配位引起荧光猝灭。由于乙酰半胱氨酸中巯基上的硫离子与Cu2+的亲和力很强,可从钙黄绿素-铜(Ⅱ)的络合物中夺取铜离子而使钙黄绿素游离出来,从而使体系的荧光得以恢复,并且荧光恢复的程度与加入乙酰半胱氨酸的量在一定范围内成线性。结论:建立了一种测定乙酰半胱氨酸的荧光分析新方法,该方法的线性范围为6.0 10-6~1.4 10-5 mol/L,检出限为4.010-6 mol/L。 相似文献
86.
该文采用 19幅 (时间跨 8个月 ) 时间序列的NOAAAVHRR的归一化植被指数 (NDVI) 最大值合成影像遥感数据, 经过主分量分析 (Principlecomponentanalysis, PCA) 处理后, 用非监督分类方法的ISODATA算法, 对中国东部地区的 (五省一市 ) 植被进行分类, 结果可以分出 2 8种土地覆盖类型, 除了两种类型为水体和城市或裸地外, 其余 2 6种类型均为植被类型, 根据中国植被分类系统, 这 2 6类可以归并为 6大植被类型 :1) 常绿阔叶林 ;2 ) 针叶林 ;3) 竹林 ;4 ) 灌草丛 ;5 ) 水生植被 ;6 ) 农业植被。用 1∶10 0 0 0 0 0数字化《中国植被图集》的植被类型检验遥感分类结果表明, 针叶林、灌草丛、常绿阔叶林和农业植被的分类具有较高的位置精度和面积精度, 位置精度分别为 79.2 %、91.3%、6 8.2 %和 95.9%, 面积精度分别达到 92.1%、95.9%、6 3.8%和 90.5 %。这 6大植被类型在地理空间上的分布规律与中国东部常绿阔叶林区植被的地带性分布基本一致。 相似文献
87.
入侵植物加拿大一枝黄花与乡土植物芦苇的相互化感作用 总被引:1,自引:0,他引:1
以加拿大一枝黄花和芦苇的共优群落和各自单优群落的种子为化感受体,分析其分别在加拿大一枝黄花和芦苇5个浓度梯度(12.5、25、50、100和200mg·mL-1)浸提液处理下的发芽率和芽长差异,研究2种植物的相互化感作用规律.结果表明:2种植物在共优群落中的千粒重和蒸馏水培养下的发芽率均比单优群落大.加拿大一枝黄花的浸提液对自身种子发芽率在单优和共优群落中均具有在低浓度下(12.5、25 mg·mL-1)轻微促进、中高浓度下(50、100和200mg·mL-1)强烈抑制的作用,其中对共优群落种子的抑制作用尤为显著;而芦苇浸提液对加拿大一枝黄花种子的影响无明显规律.加拿大一枝黄花的种子芽长在单优和共优群落中均随自身浸提液浓度的升高趋于减小,随芦苇浸提液浓度的升高呈波动减小趋势.在芦苇和加拿大一枝黄花浸提液处理下,芦苇种子发芽率在单优群落中均显著大于共优群落(P<0.05),但2种浸提液处理间无显著差异. 相似文献
88.
A new species of Sabellaria is described from the southeast coast of Brazil and compared with related species known from South or North America. 相似文献
89.
90.
DA‐WEI ZHANG FEI XU ZHONG‐WEI ZHANG YANG‐ER CHEN JUN‐BO DU SHU‐DAN JIA SHU YUAN HONG‐HUI LIN 《Plant, cell & environment》2010,33(12):2121-2131
Mitochondrial alternative oxidase (AOX), the unique respiratory terminal oxidase in plants, catalyzes the energy wasteful cyanide (CN)‐resistant respiration and plays a role in optimizing photosynthesis. Although it has been demonstrated that leaf AOX is upregulated after illumination, the in vivo mechanism of AOX upregulation by light and its physiological significance are still unknown. In this report, red light and blue light‐induced AOX (especially AOX1a) expressions were characterized. Phytochromes, phototropins and cryptochromes, all these photoreceptors mediate the light‐response of AOX1a gene. When aox1a mutant seedlings were grown under a high‐light (HL) condition, photobleaching was more evident in the mutant than the wild‐type plants. More reactive oxygen species (ROS) accumulation and inefficient dissipation of chloroplast reducing‐equivalents in aox1a mutant may account for its worse adaptation to HL stress. When etiolated seedlings were exposed to illumination for 4 h, chlorophyll accumulation was largely delayed in aox1a plants. We first suggest that more reduction of the photosynthetic electron transport chain and more accumulation of reducing‐equivalents in the mutant during de‐etiolation might be the main reasons. 相似文献