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51.
茶园冬季乔木落叶的分解和矿质元素释放   总被引:1,自引:0,他引:1  
在我国南方存在着一种传统植茶方式——茶林复合生态系统,近年来人们已逐步认识到它在维持土壤肥力,抗御自然灾害和保证茶叶内质特性等方面的作用,然而对冬季乔木落叶分解和矿质元素释放的作用尚无报道。本文是对安徽省黄山市休宁县茶树-乌桕复合园和茶树-板栗复合园的冬季乔木落叶分解的研究,为全面认识茶林复合生态系统的性质提供依据。  相似文献   
52.
A majority of the potential health benefits of green tea, including the potential to prevent cognitive decline, have been attributed to epigallocatechin gallate (EGCG). Sunrouge is a green tea cultivar that contains EGCG and several other bioactive components such as quercetin, myricetin, cyanidin and delphinidin. We compared the effects of Sunrouge and Yabukita, the most popular Japanese green tea cultivar, on cognitive function in the senescence-accelerated mouse Prone8. These mice were fed an experimental diet containing Sunrouge extract (SRE) or Yabukita extract (YBE). SRE feeding significantly prevented cognitive decline, whereas YBE feeding had little effect. Moreover, SRE feeding prevented elevation of the amyloid-β42 level while improving the gene expression of neprilysin and decreasing beta-site APP-cleaving enzyme 1 in the brain. These preventive effects of SRE against cognitive decline were attributed to the characteristic composition of Sunrouge and strongly suggest that consumption of this cultivar could protect against age-related cognitive decline.  相似文献   
53.
The stereoselective degradation of indoxacarb enriched with (+)‐S‐indoxacarb (S/R:70/30) was investigated in three typical green teas. A convenient and precise chiral method was developed and validated for measuring indoxacarb enantiomers in green tea. The developed method was based on high‐performance liquid chromatography coupled with tandem mass spectrometry using a Chiralpak IC column. The stereoselective degradation of indoxacarb enantiomers showed that the (+)‐S‐enantiomer dissipated faster than the (?)‐R‐enantiomer in all three typical tea farms. However, no enantiomerization was observed after applying pure (+)‐S‐indoxacarb. Residues on tea plant of the active ingredient (+)‐S‐indoxacarb from suspension concentrate (SC) was more persistent than that from emulsifiable concentrate (EC). Chirality 27:262–267, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
54.
Cigarette beetle, Lasioderma serricorne (F.), is a common food-product pest widely found in homes. This paper investigated the relationship between the number of infesting cigarette beetles and the phenolic content of pennywort tea made from young and mature leaves during one-year storage. It was found that cigarette beetles started to appear in tea bags after six months of storage. More adults were found than larvae and pupae. In addition, the number of cigarette beetles infesting pennywort tea made from mature leaves was higher than when it was made from young leaves. The amount of phenolic compounds in pennywort tea was analyzed by Folin–Ciocalteau assay. The results of a regression analysis indicated that the number of adult cigarette beetles correlated negatively with the amount of phenolic compounds in pennywort tea made from young leaves – when the total phenolic content decreased, the number of infesting cigarette beetles increased (r2 = 0.80). The number of larvae and pupae showed a weak negative correlation with the amount of phenolic compounds (r2 = 0.40 and r2 = 0.56, respectively). Similar correlations were found in pennywort tea made from mature leaves, but the number of infesting beetles was higher due to the lower phenolic content of the mature leaves.  相似文献   
55.
从茶树中克隆了6个水通道蛋白(aquaporin,AQP)基因的cDNA全长序列,根据序列相似性和系统进化分析结果,分别命名为CsNIP1;1、CsNIP5;1、CsPIP2;1、CsPIP2;2、CsTIP1;1和CsTIP2;2。氨基酸序列特征分析表明,6个基因的编码氨基酸序列长度在250~301个氨基酸残基,分子量在25.186~30.728kD之间;均为疏水性蛋白,并都含有6个跨膜螺旋;6个基因均含有MIP蛋白家族的特征序列HF/I/VNPA/SI/L/VTI/FA/G和NPA(Asn-Pro-Ala)基序,以及类似沙漏状的跨膜三级结构。荧光定量PCR分析显示:这6个基因在根、茎、叶和花中均表达,且在根中的表达水平最高,表明它们与茶树根系的物质转运密切相关;CsAQPs基因的表达受ABA、高盐、干旱和低温胁迫的调控,表明它们可能参与茶树抗逆响应。  相似文献   
56.
为了合理利用和保护天敌进行卵形短须螨、双斑长跗萤叶甲和假眼小绿叶蝉的综合防治,用灰色系统分析方法和生态位分析法对合肥地区白毫早茶园3种主要害虫与其捕食性天敌在数量、时间、空间等方面关系进行分析,利用害虫与天敌关系密切指数之和综合评判9种天敌与3种害虫关系密切的前四位天敌。2015年卵形短须螨的前四位天敌是鳞纹肖蛸(5.3079)、三突花蟹蛛(5.1716)、锥腹肖蛸(4.8367)和草间小黑蛛(4.7869);2016年前四位天敌依次是三突花蟹蛛(5.3975)、鳞纹肖蛸(4.9414)、茶色新圆蛛(4.8757)、锥腹肖蛸(4.6815)。对两年结果综合分析,卵形短须螨的前四位天敌依次是三突花蟹蛛(10.5691)、鳞纹肖蛸(10.2493)、茶色新圆蛛(9.6353)和锥腹肖蛸(9.5182)。2015年双斑长跗萤叶甲的前四位天敌依次是锥腹肖蛸(5.6926)、异色瓢虫(5.6976)、八斑球腹蛛(5.5101)和斜纹猫蛛(5.4552);2016年依次是茶色新圆蛛(5.2909)、锥腹肖蛸(5.2710)、鳞纹肖蛸(5.1063)和斜纹猫蛛(5.0703)。对两年结果综合评判,双...  相似文献   
57.
58.
绿茶乙醇浸提技术研究   总被引:1,自引:0,他引:1  
以工业生产上的水提技术为参照,以成品绿茶为材料,探讨乙醇浸提条件下,乙醇浓度、浸提温度、浸提时间、料液比、浸提次数等因子对醇提过程中茶汤品质成分动态浸出规律的影响。结果表明,采用50%乙醇、温度80℃、料液比1/25、连续2次、每次浸提20 min的浸提技术参数,茶叶各品质成分的浸出率最高,总浸出物、氨基酸、茶多酚、蛋白质、碳水化合物的浸出量分别是常规水提的1.39、1.09、1.44、1.52、1.23倍。从茶叶品质成分浸出率的角度考虑,在此技术参数下,用乙醇浸提绿茶优于水提。  相似文献   
59.
Species of Penicillium and Trichoderma were found to dominate the rhizosphere of established tea bushes in a detailed study conducted from various tea growing locations in India. Penicillium erythromellis, P. janthinellum, P. raistrickii, Trichoderma pseudokoningii and T. koningii were found to be closely associated with tea roots. While seasonal fluctuation was observed in the case of Penicillium spp., the population of Trichoderma spp. showed less variation during the year. Both species were sensitive to low temperatures. In general, fungi associated with the tea rhizosphere were found to prefer a mesophillic temperature range (15 °C to 35 °C). The dominant species of Penicillium and Trichoderma also exhibited tolerance to lower temperatures, i.e., 5 to 10 °C on agar plates. Most fungi were able to grow in a wide range of pH (4 to 12). Lowering of soil pH in the rhizosphere of tea bushes was positively correlated with the age of the bush and may have affected the development of a specific microbial community in the rhizosphere.

The populations of Penicillium and Trichoderma species were inversely correlated with the populations of two most dominant rhizosphere bacteria, Bacillus subtilis and B. mycoides. Both Bacillus species have been shown to have antagonistic activity against these two fungi under in vitro conditions. The present study demonstrates the existence of a similar antagonism under in situ conditions in the rhizosphere of established tea bushes.  相似文献   

60.
湖南省茶树害虫地理区划分析   总被引:1,自引:0,他引:1  
通过湖南省茶树害虫的系统调查,查明湖南省茶树害虫(害螨)共302种,根据其在湖南省各地(市)的分布,编成"0,1"分布数据表,然后进行聚类分析.根据聚类结果,参考地理、气候、茶树的种植历史和种植面积以及其他动物类群方面的研究和前人的工作,把湖南省茶树害虫分成4个区:湘北环湖平原丘岗区,湘中、湘东丘陵区,湘西山区,湘南山地丘陵区,并分别叙述了各区的特点.  相似文献   
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