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排序方式: 共有327条查询结果,搜索用时 21 毫秒
1.
介绍了山地橄榄2种病害:叶斑病、炭疽病;5种虫害:橄榄星室木虱、黑刺粉虱、恶性叶甲、橄榄枯叶蛾、橄榄野螟的主要特征和危害症状,并提出了防治措施。 相似文献
2.
Edgar G. GUTIÉRREZ Isabela VIVAS-TORO Daniela CARMONA-RUÍZ David VILLALOBOS-CHAVES Bernal RODRÍGUEZ-HERRERA Melina Del REAL-MONROY Gloria LEÓN-AVILA Jorge ORTEGA 《Integrative zoology》2021,16(5):646-658
Ectophylla alba is a tent-making bat that roosts in mixed-sex clusters comprising adults and offspring. Our goal was to determine the genetic identity of individuals belonging to different roosting groups. We tested the hypothesis of kin selection as a major force structuring group composition. We used 9 microsatellites designed for E. alba to determine the genetic identity and probability of parentage of individuals. We analyzed parentage and kinship using the software ML-Relate, GenAIEx, and Cervus. The obtained relationship probabilities (0.5) revealed a clear maternal relationship between female adults and offspring with allele compatibility, and at least 5 relationships between male adults and pups. We found a low degree of relatedness within roosting groups. Between roosting groups at different sites, the mean probability of a half-sibling relationship ranged from 0.214 to 0.244 and, for full-sibling relationship, from 0.383 to 0.553. Genetically, adult individuals were poorly related within clusters, and kinship as an evolutionary force could not explain group membership. 相似文献
3.
Effect of biologically active substances present in water extracts of white mustard and coriander on antioxidant status and lipid peroxidation of mouse C2C12 skeletal muscle cells 下载免费PDF全文
K. Zielniok K. Szkoda M. Gajewska J. Wilczak 《Journal of animal physiology and animal nutrition》2016,100(5):988-1002
Coriander and white mustard, an annual plants originated in the Mediterranean region, have been cultivated and used as spices for a long time. Recent studies have shown that they may constitute a potential source of phenolic compounds. The aim of this study was to evaluate the content of polyphenols in coriander and white mustard water extracts and to investigate their antioxidant activity in C2C12 mouse skeletal muscle cells, which serve as a good model of cells with intensive metabolism. HPLC analysis showed that polyphenols were able to permeate from the water extracts of studied plants into the undifferentiated myoblasts as well as myocytes undergoing differentiation, increasing the concentration of reduced glutathione and upregulating glutathione reductase and peroxidase activity. White mustard and coriander extracts also decreased the levels of oxysterols and sum of tiobarbituric acid reactive substances (TBARS) in both: myoblasts and differentiating myocytes, demonstrating protective effect on cell membranes. The obtained results indicate that polyphenols synthesized by both herbs may have beneficial effects on muscle tissue. 相似文献
4.
为了观察磁处理水培养液对2种十字花科植物莱菔与白芥种子发芽生长的影响.使用不同强度的磁处理水培养液对莱菔种子和白芥种子进行处理,设置对照组,7d统计发芽率、根长、根重,测相对电导率。结果表明:0.08T、0.10T强度磁处理水培养液处理的莱菔子与白芥子发芽和根生长情况均好于对照组(P〈O.05).0.08T、0.10T磁处理水培养液处理的两种幼株的电导率均低于对照组。说明磁处理水培养液对两种十字花科植物莱菔与白芥种子发芽生长有影响,其生长情况与磁场强度有关。 相似文献
5.
供氮水平对田间桑树叶片产量及其生理特性的影响 总被引:2,自引:0,他引:2
为了探寻龙桑一号的适宜施氮量,从而指导桑农科学施用氮肥,以桑树品种龙桑一号为试验材料,在大田条件下研究了不同供氮(纯氮)水平(0、48.3、96.6、144.9、193.2和241.5kg.hm-2)对桑树叶片产量及其生理特性的影响情况。结果表明:当施氮量为0~193.2kg.hm-2时,桑树单株枝条数、单枝叶片数、单叶面积、单叶质量和单株产叶量均随供氮水平的增加而增加,而当施氮量达到241.5kg.hm-2时,桑树单叶面积、叶片质量和单株产叶量反而有所降低;施氮量在0~144.9kg.hm-2范围内,桑树叶片中的全氮(N)和全磷(P)含量均随施氮量的增加而提高,而当施氮量超过144.9kg.hm-2时,叶片中的全氮和全磷含量随着施氮量的增加反而有所降低,这说明施氮量过高反而降低了桑树对N和P的吸收;随着供氮水平的增加,桑树叶片中的叶绿素含量、可溶性蛋白和可溶性糖含量均随施氮量的增加而增加。从氮肥对桑树产叶量及其生理特性的影响情况来看,桑树品种龙桑一号田间的最佳施氮量为144.9~193.2kg.hm-2。 相似文献
6.
Stems of Chenopodium album . and Sinapis arvensis . and leaves of Lolium perenne . were cut with a CO2 laser or with a pair of scissors. Treatments were carried out on greenhouse-grown pot plants at three different growth stages and at two heights. Plant dry matter was measured 2 to 5 weeks after treatment. The relationship between dry weight and laser energy was analysed using a non-linear dose–response regression model. The regression parameters differed significantly between the weed species. At all growth stages and heights S. arvensis was more difficult to cut with a CO2 laser than C. album . When stems were cut below the meristems, 0.9 and 2.3 J mm−1 of CO2 laser energy dose was sufficient to reduce by 90% the biomass of C. album and S. arvensis respectively. Regrowth appeared when dicotyledonous plant stems were cut above meristems, indicating that it is important to cut close to the soil surface to obtain a significant effect. When cutting L. perenne plants with 2-true leaves at a height of 2 cm from the soil surface with a laser, the biomass decreased significantly compared with plants cut by scissors, indicating a delay in regrowth. This delay was not observed for the dicotyledonous plants nor for the other growth stages of L. perenne . 相似文献
7.
剪股颖属植物遗传分化及系统关系的分子标记研究 总被引:4,自引:3,他引:4
剪股颖属植物形态变异大、倍性复杂、种间易于杂交,导致异名多、分类混乱。本研究采用4种分子标记技术,对包括匍茎剪股颖、巨序剪股颖及红顶草在内的7种剪股颖,共58个个体的遗传分化和系统关系进行研究。根据谱带清晰程度及多态性,筛选出9个RAPD引物、2个SSR引物、5个ISSR引物及1个SCAR标记,并建立了最适的PCR反应条件。采用最大简约法和距离法对7种剪股颖植物进行系统树分析,并用靴带检验法计算内部分支的支持率。启发式搜索得到的简约树和由UPGMA方法得到的表征树近乎相同,其中,匍茎剪股颖和红顶草构成单系类群并得到100%的置信支持。红顶草显示了匍茎剪股颖特异性特征谱带,但同时具有不同于匍茎剪股颖的遗传分化,支持将红顶草视为匍茎剪股颖一个变种的观点。对匍茎剪股颖与巨序剪股颖间的遗传分化进行了探讨。 相似文献
8.
柴达木地区新疆杨扦插育苗试验 总被引:1,自引:0,他引:1
通过新疆杨插穗催根不同处理方法和扦插时间对比试验,总结出柴达木地区新疆杨扦插育苗过程中最佳的插穗催根方法和扦插时间。 相似文献
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