首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 609 毫秒
1.
为控制不同品种成品茶的农药残留,研究目前部分乌龙茶中超标的4种化学农药在新梢加工过程中的降解。以凤圆春、大叶乌龙、白芽奇兰、毛蟹和黄旦5个乌龙茶品种为试验材料,将4种农药(联苯菊酯、甲氰菊酯、氯氰菊酯和优乐得)喷施于茶树,7d后采摘鲜叶,一部分直接烘干固样,另一部分加工成干茶,利用气相色谱分析技术,分别分析检测农药残留量。联苯菊酯的降解率在10.72%~53.47%,甲氰菊酯的降解率在9.09%~99.45%,氯氰菊酯的降解率在21.59%~92.23%,优乐得的降解率在16.67%~100%。施用联苯菊酯,较易生产出符合出口标准的乌龙茶;不同乌龙茶品种不同农药在加工过程中的降解存在一定的差异。  相似文献   

2.
正无性系品种由单一亲本无性繁殖育成,其后代表现型一致。在相同的采管制茶工艺条件下,其品质基本一致,有利于集约化生产和创品牌。福建是主产乌龙茶的省,是以品种作为茶叶品名。如用铁观音种制的乌龙茶叫铁观音,乌龙种制的叫乌龙。福建安溪县有5.33万hm2茶园,其品种基本上是无性系铁观音种,创造名茶铁观音驰名中外,是我国唯一以产茶为主的百强县。浙江省也于20世纪70年代开始推广龙井种,创造了西湖龙井和大佛龙井  相似文献   

3.
为了解贵州省茶叶的农药残留及重金属状况,检测并分析了贵州省9个市(州、地)茶叶产业基地的茶叶样品中氟氯氰菊酯、氯氰菊酯、联苯菊酯、杀螟硫磷、三氯杀螨醇等农药残留量以及重金属铅的含量。结果表明,氟氯氰菊酯、杀螟硫磷和三氯杀螨醇均未检出,氯氰菊酯、联苯菊酯、铅均有不同程度的检出,但未超标,茶叶中上述5种农药残留量较少和重金属铅较低。  相似文献   

4.
茶树新梢叶片叶绿素含量与黑刺粉虱选择性的关系   总被引:1,自引:1,他引:0  
为了明确不同茶树品种(种质)新梢叶绿素含量与黑刺粉虱选择性的关系,为抗虫品种选育的早期鉴定提供依据,采用丙酮分光光度法测定了9份不同抗性茶树新梢叶片的叶绿素含量,分析了茶树新梢叶绿素含量与黑刺粉虱选择性的相关性。研究表明,9份茶树种质新梢叶片的叶绿素总量差异达到显著水平(F=4.323,P<0.05)。其中,‘丹桂’、‘优3’、‘铁观音’、‘优510’、‘玉龙’和‘毛蟹’等种质的新梢叶片叶绿素总量较高,分别为3.72、3.49、2.85、2.74、2.69和2.61 mg/g;而‘黄旦’、‘福云10号’和‘福云6号’等品种的叶绿素总量较低,分别为1.83、1.84和1.85 mg/g。茶树种质新梢叶绿素总量、叶绿素a含量和叶绿素b含量与黑刺粉虱单位叶面积产卵量有一定负相关,但相关不显著(P>0.05);而与黑刺粉虱世代存活率有显著或接近显著水平的负相关(P<0.05)。表明新梢叶绿素总量、叶绿素a含量和叶绿素b含量较高的茶树种质,对黑刺粉虱的抗虫性较强;反之,则抗虫性较弱。  相似文献   

5.
一株高效降解氯氰菊酯细菌的分离鉴定及降解特性   总被引:7,自引:1,他引:6  
从长期使用氯氰菊酯的土壤中筛选分离出三株优势菌,编号为LF-1、LF-2和LF-3。选择对氯氰菊酯降解潜力最高的菌株LF-1进行鉴定和降解特性研究。根据生理生化特征以及16SrDNA序列同源性比对将LF-1初步鉴定为kurthia sp.;降解特性结果表明,LF-1降解氯氰菊酯最适pH和温度分别为7,35℃;在最佳降解条件下培养8 d,对100 mg/L氯氰菊酯降解率达80.15%,LF-1还能降解甲氰菊酯、联苯菊酯等菊酯类农药。经SDS或EB消除质粒后,LF-1降解氯氰菊酯的能力丧失, 明该菌降解基因可能位于质粒DNA。  相似文献   

6.
记从科技部了解到,“十五”期间,国家863计划现代农业研究在农药残留降解与检测技术上获得6项突破性进展,为农产品生产保障体系建立提供了有效的技术支撑和保障。第一,化学农药多残留免疫检测技术研究取得重要突破,实现了对同类农药的同时在线检测。以间苯氧基苯甲酸(PBA)为半抗原,通过活性酯法与BSA偶联后免疫新西兰大白兔,获得对多种菊酯类农药有免疫学反应的通用抗体。该抗体对氯菊酯、甲氰菊酯、氯氰菊酯、三氟氯氰菊酯、溴氰菊酯、功夫菊酯、二氯苯醚菊酯均有特异性识别,而对氰戊菊酯识别弱;以二乙基膦酸乙酸为半抗原,  相似文献   

7.
拟除虫菊酯类农药在人参中的多残留方法研究   总被引:2,自引:1,他引:1  
建立了人参样品中氯菊酯、联苯菊酯、氟氯氰菊酯、氰戊菊酯、溴氰菊酯、甲氰菊酯和三氟氯氰菊酯7种拟除虫菊酯类杀虫剂的多残留气相色谱分析方法(GC),用乙腈提取人参样品,石墨炭黑-氨基串联柱净化,经DB-1701石英毛细管柱(30 m×0.25 mm×0.25 μm)分离后,采用GC-μECD测定。结果表明在0.05~1 mg/kg的线性范围内,相关系数(r)分别为0.9993、0.9995、0.9992、0.9996、0.9988、0.9993、0.9993。测定结果高、中、低3个水平的平均回收率在79.1%~103.3%之间,相对标准偏差(RSD)在3.6~9.7之间,检出限在0.0008~0.03 mg/kg之间。方法简便、快速、净化效果好,适合人参中痕量拟除虫菊酯类农药残留的同时测定。  相似文献   

8.
在已筛选出低农药残留量的乌龙茶种质资源的基础上,本试验研究了茶树叶片表面特征、解剖结构与不同品种抗农药残留的关系,初步明确了茶树对农药残留的抗性机制:茶树品种对农药残留的抗性与叶尖形状、角质层同栅栏组织的比值、角质层同海绵组织的比值、上表皮同角质层厚度的比值有较密切关系。低农残的茶树资源具有如下特征:叶尖急尖、角质层同栅栏组织厚度之比低、角质层同海绵组织厚度之比低、上表皮同角质层厚度之比较高;反之为高农残的茶树资源。  相似文献   

9.
[研究目的]为探索茶树对农药残留的抗性机制,[方法]在已筛选出低农药残留量的乌龙茶种质资源的基础上,该文研究了茶树叶片表面特征、解剖结构与不同品种抗农药残留的关系.[结果]结果表明:茶树品种对农药残留的抗性与叶尖形状、角质层同栅栏组织厚度的比值、角质层同海绵组织厚度的比值、上表皮同角质层厚度的比值有较密切关系.[结论]低农残的茶树资源具有如下特征:叶尖急尖、角质层同栅栏组织厚度之比低、角质层同海绵组织厚度之比低、上表皮同角质层厚度之比较高;反之为高农残的茶树资源.  相似文献   

10.
在反复试验的基础上,建立了菜用大豆中甲氰菊酯残留量定量检测的气相色谱法。同时,通过田间试验研究了菜用大豆中甲氰菊酯残留量的消解动态,以及对其安全使用技术进行示范试验。对分析方法的适合性测定结果表明,方法的回收率为94.2%-109.1%,相对标准偏差(RSD)为1-36%-3.15%,最小检出量0.001ng,最低检测浓度为0.001mg/kg,该分析方法简便、准确、能满足实际样品分析。对菜用大豆中甲氰菊酯残留消解动态及安全使用技术的研究结果显示。甲氰菊酯的不同施用剂量在菜用大豆中原始沉积量有较大的差别,在菜用大豆同一生长季节不同施用剂量的消解速率基本一致;4g在不同生长季节的消解速率却略有差异,早季的消解速率〉晚季的消解速率,早季的半衰期(DT50)为4.1d,消解99%所需要的时间(T99)为27.1d,而晚季的DT50为4.3-4.5d,T99为29.0-30.0d。施用甲氰菊酯有效成分90.00g/hm^2,按常规施药方法施用1次,施药后15d的残留量均〈0.5mg/kg,25d的残留量均〈0.1mg/kg,而间隔期7d连续施用2次,在第二次施药后18d的残留量均〈0.5mg/kg,28d的残留量均〈0.1mg/kg,对照GB2763-2005及日本的MRL,其产品符合于中国或日本规定的质量安全要求。  相似文献   

11.
Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.  相似文献   

12.
Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.  相似文献   

13.
G. H. Kroon 《Euphytica》1994,76(1-2):125-125
Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.  相似文献   

14.
Jens Jensen 《Euphytica》1979,28(1):47-56
Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.  相似文献   

15.
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...  相似文献   

16.
Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.  相似文献   

17.
P. A. York  R. Cook 《Euphytica》1989,43(1-2):135-141
Summary Reactions of 13 grasses to Meloidogyne naasi varied with species; ryegrasses, fescues and their hybrids were generally susceptible and cocksfoot and timothy resistant. Marked variation in host resistance levels occurred between genotypes within cultivars.Selection of single plants, followed by tests on replicate tillers, identified resistant and susceptible genotypes in both Italian and perennial ryegrass cultivars. Resistant plants had few nematode-induced galls and fewer females and eggs than susceptibles. There was more or less continuous variation, with many genotypes intermediate between extremes of resistance and susceptibility. Selected resistant and susceptible genotypes are of use in assessing variation in nematode populations and as controls for breeding and selection programmes.  相似文献   

18.
Lentil production is limited by lack of moisture and unfavorable temperatures throughout its distribution. Waterlogging and salinity are only locally important. Progress has been made in breeding for tolerance to drought through selection for an appropriate phenology and increased water use efficiency and in breeding for winter hardiness through selection for cold tolerance.The diseases rust, vascular wilt, and Ascochyta blight, caused by Uromyces viciae-fabae, Fusarium oxysporum f. sp. lentis, and Ascochyta fabae f. sp. lentis, respectively, are the key fungal pathogens of lentil. Cultivars with resistance to rust and Ascochyta blight have been released in several countries and resistant sources to vascular wilt are being exploited. Sources of resistance to several other fungal and viral diseases of regional importance are known. In contrast, although the pea leaf weevil (Sitona spp.) and the parasitic weed broomrape (Orobanche spp.), and to a lesser extent the cyst nematode (Heterodera ciceri), are significant yield reducers of lentil, no sources of resistance to these biotic stresses have been found. Directions for future research in lentil on both biotic and abiotic stresses are discussed.  相似文献   

19.
Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.  相似文献   

20.
[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号