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1.
亚热带丘陵茶园间作白三叶草的生态效应   总被引:33,自引:0,他引:33  
在亚热带丘陵区1a生幼龄茶园通过连续4a的大田对比试验,研究了茶园间作白三叶草的生态效应,结果发现:茶园间作白三叶草降低了土壤容重,提高了土壤孔隙度、有机质、全N、水解N的含量、K的活性、蚯蚓的数量和生物量,消耗了部分有效P;增加了土壤关键层次(0—20cm)和关键时期(4~6月)的水分含量,延缓和缩短了夏季高温干旱与秋季持续干旱时间;获得了土壤降温时增温、保温与升温时降温的双向动态调控效果,增加了同一层次土壤温度的稳定性,延缓了高温和低温的出现时间,缩短了过度高温时间,减少了高温对茶树生长产生的影响;抑制了杂草生长,增加了天敌的种类和种群数量,减少了虫害发生率。从而形成了立地环境.茶树.伴生生物群落系统自我调节的动态平衡,促进了茶树生长,改善了茶叶品质,显著增加了茶叶产量。与清耕茶园相比,茶园间作白三叶草后,春秋茶的酚氨比分别下降了17.10%和30.90%,产量提高了32.65%。  相似文献   

2.
伊克昭盟项目区水土保持的生态效益   总被引:4,自引:0,他引:4  
根据对伊克昭盟世行项目区的监测数据,分析了项目实施后水土保持的生态效益。结果表明,项目实施后,改善了土壤的理化性质,增加了土壤肥力;同时,提高了当地的林草植被覆盖度,改善了局地气候,促进了生物多样性的恢复和保护。  相似文献   

3.
亚热带丘陵茶园间作白三叶的土壤环境调控效果   总被引:16,自引:1,他引:15  
在亚热带丘陵区1年生幼龄茶园通过连续4年间作白三叶大田试验,研究了其对茶园土壤环境及茶叶品质、产量的影响,结果表明,茶园间作白三叶降低了土壤容重,提高了土壤孔隙度、有机质、全氮、水解氮的含量及钾的活性,消耗了部分有效磷;增加了土壤关键层次(0~20cm)和关键时期(4~6月)的水分含量,延缓和缩短了夏季高温干旱与秋季持续干旱时间;获得了土壤降温时增温、保温与升温时降温的双向动态调控效果.增加了同一层次土壤温度的稳定性,延缓了高温和低温的出现时间,缩短了过度高温时间。从而促进了茶树生长,改善了茶叶品质,显著增加了茶叶产量。与清耕茶园相比,茶园间作白三叶后,春秋茶的酚氨比分别下降了17.10%和30.90%,产量提高了32.65%。  相似文献   

4.
花菇的冷冻干燥技术研究   总被引:1,自引:0,他引:1  
实验研究用板层导热法研究了花菇的冻干特性,获得了新鲜花菇的冻干曲线,分析了花菇冻干过程,测定和比较了新鲜花菇和冻干花菇的营养成份。证实试验机的适应性并确定了花菇的冻干工艺,为工业生产提供了理论依据和参考价值。  相似文献   

5.
对华北落叶松鞘蛾和兴安落叶松鞘蛾的形态特征进行了研究,与容易混淆的欧洲落叶松鞘蛾进行了比较。更正了兴安落叶松鞘蛾的学名,肯定了华北落叶松鞘蛾的分类学地位,并进行了重新描述。文中提供了以上3种落叶松鞘蛾的成虫、雌雄外生殖器等特征图,给出了它们的区别要点。  相似文献   

6.
上海市细胞生物学学会于1986年12月26日至27日在上海召开了年会。26日上午举行了年会开幕式,会上由庄孝僡理事长致开幕词,胡兆庆秘书长作了学会的工作报告。大会并邀请了细胞生物学研究所王亚辉所长作了细胞生物学的趋向和发展战略的报告。有150余人参加了会议。26日下午和27日上午进行了分组论文报告,共报告了64篇论文,年会显示了近年来上海市细胞生物学研究取得的成就。会议期间还邀请了下述同志作了小组专题报告。庄孝僡:关于中胚层的决定和分化的问题;顾国彦:胞质分裂时蛙卵表面运动;鲍璿:体外培养神  相似文献   

7.
降脂红曲的菌学性质及化学成分的分析   总被引:4,自引:0,他引:4  
本文对No.4降脂红曲的生理特性进行了分析,测定了其一般的化学成分,将No.4红曲米的色调和色价与其它红曲米进行了对比,确定了该红曲的最适培养条件,制定了No.4红曲米的质量标准,并验证了它可作为糖化酶的生产菌。  相似文献   

8.
合理施肥对银杏园土壤肥力和酶活性的影响   总被引:2,自引:0,他引:2  
首次研究合理施肥对银杏园土壤肥力和酶活性的影响,结果表明合理施肥,改善了土壤理化性状,显著地提高了土壤肥力和土壤酶的活性;从而培育了银杏发达的根群,促进了树体的生长。增加了银杏鲜根重和百叶鲜重,减少了银杏黄化株率,提高了银杏挂果株率及种核的产量和品质。  相似文献   

9.
远程教育培训给生物教学带来新的生机。夯实了专业知识,梳理了生物知识,使我认识到应该如何把握生物课堂教学,提高了课堂教学设计能力,凝聚了生物教师的力量,使老师们学到了很多知识和教学技能,解决了平时教学中的一些难题,提升了生物的教学水平。  相似文献   

10.
本文研究了一类带时滞、周期脉冲输入营养液的恒化器模型.我们得到了存在一个全局吸引的微生物灭绝周期解;同时给出了带时滞和脉冲输入系统持续生存的充分条件.我们表明了脉冲效应破坏了连续系统的平衡点产生了周期解,本文结论可用于微生物的培养.  相似文献   

11.
正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

12.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

13.
The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

14.
15.
Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.  相似文献   

16.
Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8+ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8+ T cells are involved in the pathogenesis of RE.  相似文献   

17.
18.
Shen  Jia-Yuan  Li  Man  Xie  Lyu  Mao  Jia-Rong  Zhou  Hong-Ning  Wang  Pei-Gang  Jiang  Jin-Yong  An  Jing 《中国病毒学》2021,36(1):145-148
正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).  相似文献   

19.
In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.  相似文献   

20.
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