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111.
麦套春棉主要害虫和天敌的生态位研究 总被引:5,自引:2,他引:5
调查了麦套着棉不同时期内,棉株上、中、下部棉蚜AphisgossypiiGover、棉叶螨TetranychustruncatusEhara、棉铃虫Helicoverpaarmigera(Hubner)和其主要天敌的数量。求得各期害虫与害虫、害虫与天敌、天敌与天敌之间的生态位宽度和重叠指数,并分析了它们彼此在空间上的竞争关系。 相似文献
112.
Anna Chrtková-Žertová 《Folia Geobotanica》1971,6(2):215-216
Four new taxa in the variable speciesLotus corniculatus L. has been described: var.alandicus Chrtková-?ertová, var.norvegicus Chrtková-?ertová, var.fallax Chrtková-?ertová and var.posoniensis Chrtková-?ertová. 相似文献
113.
蜡梅17个品种过氧化物同工酶的研究 总被引:14,自引:0,他引:14
采用聚丙烯酰胺凝胶电泳系统,多次进行了蜡梅17个品种的过氧化物同工酶测定。测定结果发现:蜡梅酶谱具有多态特性;蜡梅品种间酶谱差异显著,每个品种均有其特征酶谱,或以其酶带数目、Ff及活性强弱、酶带宽度与其它品种相区别。同时,采用"排序方法"和聚类分析,对蜡酶17个品种酶谱的相似程度进行了研究。研究结果表明,两种方法研究蜡梅品种的酶谱,均可达到定量比较水平,避免单一酶谱谱带确定蜡梅品种的偏阳性,为其品种鉴定与检验提供了新的依据和手段。同时,还表明,聚类分析进行的蜡梅品种酶谱聚类结果,与其形态分类相一致,但与其品种群划分不相吻合,其原因可能与蜡梅品种起源的复杂性和多源性所引起。 相似文献
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目的:提高防风种子发芽率,加大黑龙江省地道药材防风的开发力度。方法:分别采用45℃温水浸种12、24h;150w微波辐射15s、20s、25s 30s;流水冲洗防风种子3—4h;柳枝浸出液为萌发剂培养防风种子,同时培养未经处理的种子作为对照组。结果:对照组发芽率为36.67%;温浸组为60.33%;微波15s组发芽率为68.00%,20s组为74.33%,25s组为71.17%,30s组为67.33%;流水组发芽率为84.00%;柳枝组发芽率为68.67%。结论:大规模播种可采用45℃温水浸种12-24h、150w微波辐射20s、流水冲洗3—4h、柳枝浸出液为萌发剂均可提高发芽势、发芽率,缩短发芽历期,改善出芽不齐等现象。 相似文献
116.
Bright Varghese Mushira Enani Abdulrahman Alrajhi Sameera Al Johani Ali Albarak Sahar Althawadi Noura Elkhizzi Hawra AlGhafli Mohammed Shoukri Sahal Al - Hajoj 《Respiratory research》2018,19(1):259
Background
Growing evidences suggested that the Mycobacterium tuberculosis complex (MTBC) lineages can determine the clinical outcome of pulmonary and extra-pulmonary tuberculosis. However, limited data only available revealing such association of bacterial genotypes and clinical phenotypes from immigrant rich countries.Methods
A multicenter study has been carried out on a collection of 2092 (1003 extrapulmonary and 1089 pulmonary) MTBC isolates. Genotyping of all the isolates were carried out by spoligotyping and 24 loci based MIRU-VNTR typing.Results
Demographically domination of young Saudi nationals (61.4%) and men (61.2%) were found in this cohort. Lymph nodes (62.4%) and gastrointestinal sites (16.7%) were the most common anatomical sites of infection. The predominant lineages were Delhi/CAS (26.9%), EAI (14.2%) and Ghana (9.9%). Mycobacterium africanum type I and II were reported for the first time in the country among extrapulmonary cases. ‘Ancestral’ lineages M.bovis (OR-5.22; 95% CI-2.23-8.22, p-?<?0.001) and Delhi/CAS (OR-0.57; 95% CI-0.411-0.734, p-?<?0.001) were directly associated with lymph node tuberculosis and gastrointestinal tuberculosis (M. bovis-OR-0.33; 95% CI-0.085-0.567, p-0.001 and Delhi/CAS-OR-1.87; 95% CI-1.22-2.53, p-?<?0.001) respectively. Among the ‘Modern’ lineages, EAI showed significant association to central nervous system tuberculosis (OR-1.98; 95% CI-0.76-3.19, p-0.04) and Uganda-I to gastrointestinal tuberculosis (OR-2.41; 95% CI-0.77-4.06, p-0.02).Conclusions
The findings substantially contribute to the emerging evidences that MTBC lineages influence disease phenotypes and epidemiological consequences.117.
Nevena?Miti? Mariana?Stani?i? Jelena?Savi? Tatjana??osi? Nemanja?Stanisavljevi? Jovanka?Milju?-?uki? Marija?Marin Svetlana?Radovi? Slavica?Ninkovi?Email author 《Protoplasma》2018,255(6):1683-1692
Chenopodium murale L. is an invasive weed species significantly interfering with wheat crop. However, the complete nature of its allelopathic influence on crops is not yet fully understood. In the present study, the focus is made on establishing the relation between plant morphophysiological changes and oxidative stress, induced by allelopathic extract. Phytotoxic medium of C. murale hairy root clone R5 reduced the germination rate (24% less than control value) of wheat cv. Nata?a seeds, as well as seedling growth, diminishing shoot and root length significantly, decreased total chlorophyll content, and induced abnormal root gravitropism. The R5 treatment caused cellular structural abnormalities, reflecting on the root and leaf cell shape and organization. These abnormalities mostly included the increased number of mitochondria and reorganization of the vacuolar compartment, changes in nucleus shape, and chloroplast organization and distribution. The most significant structural changes were observed in cell wall in the form of amoeboid protrusions and folds leading to its irregular shape. These structural alterations were accompanied by an oxidative stress in tissues of treated wheat seedlings, reflected as increased level of H2O2 and other ROS molecules, an increase of radical scavenging capacity and total phenolic content. Accordingly, the retardation of wheat seedling growth by C. murale allelochemicals may represent a consequence of complex activity involving both cell structure alteration and physiological processes. 相似文献
118.
B. Cukrowska J. Šinkora Z. Řeháková I. Šplíchal L. Tučková R. Barot-Ciorbaru A. T. J. Bianchi R. Lodinová-Žádníková H. Tlaskalová-Hogenová 《Folia microbiologica》1995,40(4):421-430
Immunoglobulin (Ig) response to different polyclonal B-cell activators was measured by ELISA in cell culture media of thymocytes,
splenocytes and liver cells isolated from pig fetuses, 8-d-old germ-free piglets and conventionally reared pigs. Both in fetal
and in postnatal life polyclonally stimulated lymphocytes were found to produce predominantly the IgM isotype; the first IgM
formation was detected in 50-d-old fetal liver (gestation in pigs lasts 114 d). Surprisingly, 73-d-old fetal thymic cells
were shown to be induced to Ig synthesis and secretion. In contrast to splenocytes of the same age, which secreted exclusively
IgM, fetal thymocytes produced IgM, IgG and IgA. Polyclonally stimulated splenic cells as compared with thymic cells started
to produce IgA later in fetal ontogeny, whereas the IgG response was not detectable in splenic cell culture media during the
whole embryonal development and appeared only after birth. The earliest and the highest Ig stimulation was found after cultivation
of lymphocytes withNocardia delipidated cell mitogen. Interestingly, the moderate stimulatory effect of 65-kDa heat shock protein (Hsp-65) in polyclonal
IgM response of fetal splenocytes was observed. We showed that thymic B lymphocytes represent probably the first maturing
B cell population detectable in fetal life, which is able to differentiate after polyclonal stimulation into IgM as well as
IgA and IgG producing cells.
Dedicated to Professor J. Šterzl on the occasion of his 70th birthday 相似文献
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