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71.
Changes in Amino Acid Content and the Metabolism of γ-Aminobutyrate in Cucurbita moschata Seedlings 总被引:2,自引:0,他引:2
Ungerminated pumpkin (Cucurbita moschata Poir.) cotyledons contained 30 % of their dry weight as lipid and 26 % as protein, of which 93 % was globulin. There was a rapid degradation of these reserves 4 to 8 days after planting when the cotyledons had their maximum metabolic activity. About half of the mole percent of amino acids found in the globulin reserve was in arginine, glutamate, aspartate, and their amides. The cotyledons had a large soluble pool of arginine, glutamine, glutamate, and leucine. Most amino acids increased steadily in amount in the cotyledons during germination, except glutamine, ornithine, alanine, serine, glycine, and γ-aminobutyrate and these appeared in large amounts in the translocation stream to the axis tissue. Little arginine or proline was translocated. By 10 days, when translocation had decreased, amino acids accumulated. Ornithine, γ-aminobutyrate, and aspartate were rapidly utilized in the hypocotyl, while glutamine, glycine, and alanine accumulated there. Cysteine and methionine levels were low in the reserve, trans-location stream and soluble fractions. γ-Aminobutyrate-U?14C injected into cotyledons or incubated with hypocotyls was utilized in a similar fashion. The label appeared in citric acid cycle acids and in the amino acids closely related to this cycle, but the bulk of the label appeared in CO2. The labeling pattern suggests that γ-aminobutyrate was utilized via succinate, and thus entered the citric acid cycle. A close relationship between arginine, ornithine, glutamate, and γ-aminobutyrate exists in the cotyledon with all but arginine being translocated rapidly to the axis tissue where these amino acids are rapidly metabolized. 相似文献
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73.
综述蒙瓢蜡蝉属的分类研究历史,记述中国蒙瓢蜡蝉属Mongoliana Distant 7种,其中包括5新种矛尖蒙瓢蜡蝉Mongoliana lanceolata, sp. nov.,三角蒙瓢蜡蝉Mongoliana triangularis, sp. nov.,锯缘蒙瓢蜡蝉Mongoliana serrata, sp. nov.,褐斑蒙瓢蜡蝉Mongoliana naevia, sp. nov. 和曲纹蒙瓢蜡蝉Mongoliana sinuata, sp. nov.;绘制了雄性外生殖器及前翅主要特征图,并列有分种检索表.新种模式标本均保存在西北农林科技大学昆虫博物馆. 相似文献
74.
综述了中国新记录属--犀瓢蜡蝉属Angilodes的分类研究历史,研究了中国采集的种类,同意将该属归人瓢蜡蝉科Issidae,报道该属1个中国新记录种--犀瓢蜡蝉Augilodes binghami (Distant 1906),记述1个新种-端斑犀瓢蜡蝉Augilodes apicomacula,sp.nov.。提供了分种检索表。模式标本保存在西北农林科技大学昆虫博物馆。 相似文献
75.
对金针菇Flammulina velutipes单核菌丝W23的菌丝体以及与L11质配后的双核菌丝H1123菌丝体进行了转录组测序,以本实验室已获得的W23基因组为参考基因组研究两样本间差异基因,并对这些差异基因进行了GO功能和Pathway显著性富集分析。差异基因分析显示,两个样本中共有显著性差异表达的基因3 504个,其中在双核菌丝中上调、下调的基因数分别为2 151和1 353个。研究发现差异表达基因含有很多的转录因子基因、蛋白激酶以及WD40 repeat-like蛋白。Gene Ontology(GO)功能分析结果表明,extracellular region和membrane-enclosed lumen条目下的差异基因全部为上调表达,而envelope下的差异基因全部为下调表达,以利于双核菌丝分裂时锁状联合的形成而便于核的迁移。Pathway 功能富集分析结果表明,脂肪酸、氨基酸以及大部分糖类合成相关基因具有比较活跃的上调表达。说明双核菌丝主要进行营养物质的富集,为下一步在合适条件下分化成原基,进入生殖生长阶段储备物质基础。 相似文献
76.
赤眼蜂防治玉米螟的应用研究 总被引:2,自引:0,他引:2
本文系1974年在山东省邹县进行赤眼蜂防治玉米螟的研究结果。重点是摸索放蜂时间、次数、数量和蜂菌配合的防治效果,同时还探明了玉米的不同播种方式、长势及玉米螟落卵量的不同与放蜂效果的关系。研究结果表明:利用赤眼蜂防治玉米螟效果明显,卵寄生率一般可达70—90%,防治效果达60—80%。赤眼蜂每次放逢量一般以1万头为宜,寄生率可达80%左右,蜂量再多似无必要。放蜂时间要掌握在卵初期,防治效果可达82.6%,若在卵盛期放蜂,防治效果降低34.8%。放蜂的次数主要根据玉米螟全卵期的长短和赤眼蜂在当时的田间温度下发育一代所需时间而确定,一般放蜂3—4次即可。玉米的长势与赤眼蜂寄生率的关系极为密切,长势好的地块赤眼蜂的寄生率明显高于长势差的地块。以蜂灭卵,以菌扫残(幼虫),蜂菌配合可明显提高防治效果。 相似文献
77.
豆科植物与根瘤菌共生互作的结果导致了一个新的植物器官――根瘤的形成, 根瘤菌生活在根瘤中, 它们具有将氮气转化为能被植物同化的氨的能力。该文阐述了根瘤的形成过程和类型, 并主要以模式豆科植物蒺藜苜蓿(Medicago truncatula)和日本百脉根(Lotus japonicus)为例, 对近年来共生结瘤过程中宿主植物对根瘤菌结瘤因子的识别和信号传递、侵入线形成和固氮的分子基础, 以及宿主植物对根瘤形成的自主调控机制、环境中氮素营养对结瘤的影响研究进行了综述, 指出当前豆科植物与根瘤菌共生互作研究存在的问题, 并对今后的研究方向作了分析与展望。 相似文献
78.
Habitat loss and fragmentation constrain the survival of most forest‐living mammals, particularly strictly arboreal primates. Because fragment size directly affects food availability, primate survival in small fragments may depend on dietary flexibility. Here, we review the literature on the diet of 29 wild groups of Alouatta guariba clamitans inhabiting forest fragments in Brazil and Argentina. We identify general feeding patterns and analyze the influence of fragment size and latitude on diet composition. Brown howlers presented a diet composed of 402 plant species belonging to 227 genera and 80 families. Rarefaction curves suggest that the richness of top food species is similar among groups living in larger (>100 ha), medium (11–100 ha) or small (1–10 ha) fragments. On average, only 12% of the plant species used as food sources by a given group was also consumed by groups from other sites. The shorter the distance between sites, the higher the diet similarity among groups. Despite their diet flexibility, brown howlers spent >80% of the total feeding records on 6–24 species belonging to genera such as Ficus, Zanthoxylum, and Eugenia. Leaves and fruits were the plant items most consumed (65% and 22% of the total feeding records, respectively). Leaf consumption was not affected by fragment size, but it was inversely related to latitude, which may be linked to an increase in the concentration of secondary metabolites in leaves at higher latitudes. We suggest that the ability of brown howlers to exploit a large number of plant food species, including native and exotic trees, shrubs, vines, and lianas, is an important trait that contributes to their survival in highly fragmented habitats along the Atlantic forest. Similar meta‐analyses of data from other howler species are necessary to test whether such dietary flexibility is a genus‐wide pattern. Am. J. Primatol. 75:16‐29, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
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80.