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1.
HAN-QI YANG HONG WANG DE-ZHU LI 《Botanical journal of the Linnean Society. Linnean Society of London》2008,156(3):411-423
The foliage leaf epidermis of 35 species representing 12 key genera of woody bamboos of the Asian tropics was investigated using light and scanning electron microscopy. The results indicated that papillae forms and distributional patterns around the stomatal apparatus of the abaxial foliage leaf epidermis were usually constant and were of great taxonomic significance at the specific and generic levels. However, papillae characters were not suitable for dividing subtribes within woody bamboos of the Asian tropics. On the basis of papillae characters, Schizostachyum s.s. and Cephalostachyum were confirmed, but their delimitations should be modified. The transfer of Leptocanna chinensis and Schizostachyum sanguineum into Cephalostachyum was supported, and Cephalostachyum virgatum and C . pergracile were confirmed to be members of Schizostachyum s.s. The subtribe Racemobambosinae did not obtain support and Racemobambos appeared to be better placed in subtribe Bambusinae. Neomicrocalamus was supported as a close relative and better treated as a synonym of Racemobambos . Gigantochloa was closely related to Dendrocalamus . © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 411–423. 相似文献
2.
A Low-Moisture-Content Limit to Logarithmic Relations Between Seed Moisture Content and Longevity 总被引:16,自引:1,他引:15
Seeds of quinoa (Chenopodium quinoa Willd.), sunflower (Helianthusannuus L.) and linseed (Linum usitatissimum L.) showed negativelogarithmic relations between longevity and moisture contentsbetween 4.4 and 15.4, 3.2 and 13.0, and 3.2 and 15.5%, respectively,in hermetic storage at 65 °C. However, between 1.8 and 3.1,1.1 and 1.9, and 1.1 and 2.1%, respectively, longevity did notvary. The critical moisture content, below which further reductionin moisture content no longer increased longevity in hermeticstorage at 65 °C, for each species was 4.1, 2.04 and 2.7%,respectively. Quinoa, Chenopodium quinoa Willd., sunflower, Helianthus annuus L., linseed, Linum usitatissimum L., seed storage, improved viability equation, seed longevity, seed moisture content 相似文献
3.
康定虫草主要寄主斜脉蝠蛾的研究 总被引:4,自引:0,他引:4
冬虫夏草是一味名贵的中药材.四川康定虫草的主要寄主斜脉蝠蛾翅面色斑多变异,可区分成“黑白斑”和“黄毛斑”两大色斑型.经交配试验和成虫形态特征(触角、口器、翅脉、前足、雌雄外生殖器和鳞片的超微结构等)的观察,证明为同一种,经鉴定是斜脉蝠蛾(Hepialus oblifurcus Chu et Wang)**. 相似文献
4.
Various daily photon doses (daily net number of photons perunit area), provided by varying both photon flux density andphotoperiod, were applied to dormant seed populations of fourgraminaceous species tested for germination in alternating-temperatureregimes on filter papers moistened with either water or a solutionof potassium nitrate. In all four species germination was dependentupon daily photon dose, the product of photon flux density andduration, and quantified by linear relations between the probitof percentage germination and the logarithm of the daily photondose determined by probit analysis. Photon flux density andphotoperiod only influenced germination indirectly as factorsof daily photon dose, except in Echinochloa turnerana (Domin)J.M. Black at high daily photon doses where lower germinationwas observed in continuous light than in 8 h d1 photoperiod.The low energy reaction, in which increasing dose promotes seedgermination, was observed in Echlnochloa turnerana and Eragrostistef(Zucc.) Trotter but not in the populations of Brachiariahumidicola (Rendle) Schwcickerdt and Panicum maximum Jacq. usedin this study. The high irradiance reaction, in which increasingthe photon dose reduces germination, was, however, observedin all four species. In Eragrostis tef potassium nitrate influencedthe response of seed germination to light, but in the remainingspecies its influence on this relationship was either additive(Panicum maximum) or nil (Brachiaria humidicola and Echinochloaturnerana) in the alternating-temperature regimes used in thisstudy. The implications of the quantal response to photon dosefor devising optimal light regimes to be applied in laboratorytests intended to maximize seed germination are discussed. Key words: Light, seed germination, seed dormancy, grasses 相似文献
5.
An Intermediate Category of Seed Storage Behaviour?: I. COFFEE 总被引:15,自引:3,他引:12
Seeds of four cultivars of arabica coffee (Coffea arabica L.)were tested for germination following hermetic storage for upto 12 months at several different combinations of temperaturesbetween 20 °C and 15 °C and moisture contentsbetween 5% and 10% (wet basis). Most of the seeds from one cultivarwithstood desiccation to between 5% and 6% moisture content,a seed water potential of approximately 250 MPa, butthose of the remaining three cultivars were much more sensitiveto desiccation damage. Moreover, in all four cultivars, seedlongevity at cool and sub-zero temperatures, and at low moisturecontents did not conform with orthodox seed storage behaviour:viability was lost more rapidly under these conditions thanat either warmer temperatures or higher moisture contents. Theresults confirm that coffee seeds fail to satisfy the definitionsof either typical orthodox or recalcitrant seed storage behaviour.These results, therefore, point to the possibility of a thirdcategory of storage behaviour intermediate between those oforthodox and recalcitrant seeds. One of the main features ofthis category is that dry seeds are injured by low temperatures. Key words: coffee, Coffea arabica L., seed storage, seed longevity, desiccation, temperature 相似文献
6.
鸽血变虫(Haemoproteus columbae Kruse,1980)生活史研究 总被引:1,自引:0,他引:1
本文首次报告我国鸽血变虫的生活史。自然和人工感染实验证明虱蝇是其昆虫媒介。本虫的配子体进入虱蝇体内6—10天后完成孢子有性增殖。 实验观察了本虫在鸽体内无性增殖期的形态、部位及在末梢血液中配子体的发育过程,并证明其潜隐期(prepatent period)为28—30天。 本工作亦对羽虱体腔中的卵囊和子孢子作了描述,提示羽虱也可能是本虫的媒介昆虫,有待今后研究证实。 相似文献
7.
大鼠肝癌模型CBRH—3的建立及其生物学特性 总被引:8,自引:0,他引:8
用DENA诱发近交系Wistar大鼠,经三个月后得原发性肝癌,移植于同品系幼鼠,从而建立了 一株染色体众数正常,AEP阳性的大鼠移植性肝癌模型,命名为CBRH-3,病理鉴定为肝细胞型肝 癌。至今已传至60余代,目前生长稳定。 相似文献
8.
9.
一株生物表面活性剂产生菌的分离及其特性研究 总被引:2,自引:0,他引:2
模炼油厂污泥中分离得到1株生物表面活性剂产生菌C-3, 根据其生理生化特性和16S rDNA序列相似性分析, 将其鉴定为铜绿假单胞菌(Pseudomonas aeruginosa)。初步研究了其产生物表面活性剂的最适条件, 在以植物油为碳源、30°C、初始pH 8、Ca2+浓度20 mg/L、250 mL三角瓶中装75 mL发酵液的条件下, 最利于菌株的生长和生物表面活性剂产生。它的成分为糖脂类物质, 临界胶束浓度(CMC)为50 mg/L, 具有很好的增溶效果。 相似文献