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外源激素和微量元素对茶籽萌发和生理生化变化影响的研究 总被引:5,自引:2,他引:5
茶树种子经赤霉素(GA)、乙烯利(CEPA)硼酸(B)、钼酸铵(Mo)、硫酸锰(Mn)和硫酸铜(Cu)溶液处理后,子叶吸水能力、持水力、呼吸速率和过氧化氢酶活性增强,可溶性糖和蔗糖含量提高,并加速子叶蛋白质的消耗和胚对蛋白质的利用,从而促进茶籽萌发生长,增加幼苗干重,提高发芽率,其中以GA100ppm、CEPA100ppm、B1500ppm,Mo1000ppm,Mn1000ppm,Cu100ppm 相似文献
13.
茶树钾营养特性的研究 总被引:5,自引:0,他引:5
本文对我国主要茶区茶园土壤的含钾状况,茶树品种和土壤水分对茶树吸收钾的影响和茶园施肥钾肥的增产效果进行了系统研究。结果表明,我国有近60%的茶园土壤处于罐钾状态,这已成为限制茶叶高产优质的主要障碍因子之一。不同品种茶树对钾的吸收具有明显差异,它们对钻的最大速率Vmax为龙井43>碧云>苹云>碧峰>菊花春,米氏亲和常数Km为碧峰>碧云>龙井43>苹云>菊花春。干旱处理的茶树体内累积的钾和叶片的含钾量 相似文献
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Sap flow meters based on the stem heat balance method were used to measure the mass flow rates or water use in young potted tea (Camellia sinensis L.) plants of clones AHP S15/10 and BBK35. The meters were constructed on site and installed onto the stem or branch sections of field growing plants in an experiment originally designed to study the effects of plant population density and drought on the productivity and water use of young tea clones. The objective of the study was to use the SHB method as a first attempt to use sap flow meters for determining the water use of young tea growing in the field under well watered conditions in Tanzania. The results are reported and recommendation made for further work on using the technique. 相似文献
15.
The factors influencing the decision of smallholder farmers to adopt new farming technologies were studied with reference to rubber–tea intercropping in Sri Lanka. Rubber–tea intercropping has been recommended previously to rubber farmers as a means to improve productivity and income during the early pre-tapping phase of rubber growth. Although crop trials have shown that the two crops are agronomically compatible and potentially produce a combined economic yield superior to the yield of a sole crop grown on the same area of land, there is little evidence of widespread adoption of this practice among smallholder farmers in Sri Lanka. The aim of the study was to determine the major factors that influence the decision to undertake rubber–tea intercropping and to construct a predictive model that describes the likelihood of adoption of intercropping by traditional smallholder rubber growers. A rapid rural appraisal (RRA) was undertaken based on semi-structured interviews of 90 smallholder farmers in the main rubber growing low wet zone of Sri Lanka. Among a number of factors shown to significantly influence the decision to intercrop tea with rubber, three were shown to operate independently, namely level of income, source of income (i.e. solely from own farm or from farm plus additional off-farm enterprises), and availability of land considered suitable for tea cultivation. A statistical model developed through correlation and logistic analysis, which predicts the likelihood of a smallholder adopting intercropping based on these factors, is presented and discussed. The most likely combination of circumstances (82% probability) under which rubber–tea intercropping is practiced is shown to be where the farmer’s income is greater than Rs. 10,000 per month, where the farmer’s income is based solely on own farm enterprises, and where more than 80% of the farmer’s land area was judged to be suitable for tea cultivation. Conversely, 30% of smallholder farmers that chose not to intercrop did possess land suitable for tea cultivation. Qualitative responses to the RRA indicated that limitation of technical knowledge was the main problem subsequently faced by rubber farmers who had adopted rubber–tea intercropping. Results indicate that there is need for both income support through farm subsidies and further agricultural extension services, if rubber–tea intercropping is to be adopted more widely in Sri Lanka. The wider usefulness of the developed logistic model in determining the likelihood of adoption of intercropping by smallholder farmers is discussed. 相似文献
16.
茶叶提取物对抗肺癌细胞(A549)体外试验研究 总被引:1,自引:0,他引:1
观察表没食子儿茶素没食子酸酯(EGCG)、茶黄素-3、3'-双没食子酸酯(TFDG)、茶黄素(TF)、茶黄素复合物(TFs)、葡萄籽提取物(GrapeSeedExtract,GSE)、松树皮提取物(PineBarkExtract,PBE)、咖啡因(Caf)、槲寄生(VCE)和茶氨酸(The)的体外抗癌活性,通过人肺癌细胞(A549)进行体外试验,结果表明除咖啡因、槲寄生、茶氨酸的作用较小以外其他几种均有很强的促进人肺癌细胞(A549)凋亡的作用,并且EGCG的作用最强,顺序为EGCG、TFs>GSE>PBE、TFDG>TF。用作图法求得EGCG、GSE、PBE、TFDG和TF的IC50值分别为1.01μM、21.91μM、31.01μM、32.87μM和279.67μM。 相似文献
17.
石门县地处湘西北边陲,20个乡、镇(区),面积3973km^2,人口70万,是“老、少、边、穷”的大山区。其生态优越,茶生产、茶文化历史悠久,茶品质优异,是湖南产茶和旅游资源大县。本文分析了茶产业对石门县域经济的影响,提出了“十一五”规划、远景目标和加强领导、技术服务等工作措施,并探讨了质量安全、打造品牌、建设基地的技术举措。 相似文献
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本文通过对湖洋乡主要茶场的调查分析。对当前茶叶采摘存在的主要问题。提出解决问题的建议和具体措施:一是茶叶采摘上搞好分期分批采茶。严格采摘标准。加强配套措施,推广采茶机具;二是经营管理上做好技术培训与指导,完善承包责任制。健全茶叶验收制度和使用洁净用具等。 相似文献
20.
以“大鸡心”黄皮为材料,研究了不同浓度茶皂素处理对黄皮相关贮藏品质及生理活性变化的影响。结果表明,低浓度的茶皂素处理能显著抑制黄皮果实贮藏后期褐变现象,保持较高黄皮果实可溶性固形物含量及相对适宜的酸度,有效抑制了黄皮果实多酚氧化酶(PPO)、过氧化物酶(POD)活性的上升,并提升超氧化物歧化酶(SOD)的活性,其中贮藏至12 d时,低浓度处理果实PPO活性为0.39±0.03 U.g-1.min-1,低于对照组和高浓度处理组;贮藏至6 d时, SOD活性为5.07±0.08 U.g-1.min-1,显著高于对照组和高浓度处理组。而高浓度的茶皂素处理可抑制果实保护酶过氧化氢酶(CAT)的下降与脂质过氧化产物丙二醛(MDA)的积累。适宜浓度的茶皂素处理有利于减缓黄皮褐变并维持果实贮藏品质,提高其商品价值。而不同浓度茶皂素处理对黄皮果实在生理指标上具有不同的效果,具体应用浓度仍有待进一步研究。 相似文献