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1.
浙江茶情(4)     
陆德彪 《茶叶》2000,26(4):241
全国茶叶会议代表参观新昌、嵊州茶叶示范基地 8月29日,参加由农业部种植业管理司主办的"全国无公害茶叶生产现场座谈会议"的各省(市,区)代表共140余人,参观考察了新昌浙东名茶市场、新昌茶树良种场的高效良种茶园、新昌长诏水库茶场的无公害茶叶示范基地及嵊州市崇仁镇应桂岩村茶叶基地,与会代表对这二个县在抓无公害茶叶发展、抓降低农药残留、抓管理方面的经验、作法与取得的成绩给予了较高的评价.  相似文献   

2.
浙江茶情(2)   总被引:2,自引:0,他引:2  
陆德彪 《茶叶》2000,26(2):110
有机茶工程启动为应对国际"绿色壁垒"的挑战,促进茶叶产业升 级,省农业厅和省供销社于2月28日在杭州召开了全省降低农残、开发有机茶工程会议,嵊 州 、宁海、武义等20个有机茶工程试点县(市)的政府分管领导、农业(林特)局长,茶叶科研、 教育、技术监督、出入境检验检疫及企业代表参加会议,省农业厅赵宗英厅长作了"严格控 制农残、大力开发有机茶,促进浙江茶叶产业健康发展"的主题讲话.会上,发布了<有机茶>标准,介绍了开发有机茶的有关技术及成功经验.这次会议非常及时,富有成效:一是分析了形势,统一了对降低农残、开发有机茶重要性和紧迫性的认识;二是研究部署了"有 机茶工程"方案的五年规划;三是落实了当前降低农残、开发有机茶、搞好产销衔接、加强 农药管理等具体措施.  相似文献   

3.
Natural materials and plants have a long history of medical applications due to their broad range of favorable biological functions including biocompatibility, anti-bacterial, anti-oxidant and anti-inflammatory properties. Main objective of this study was to develop alginate-chitosan-hyaluronic acid (ACH) composite fibers with controlled drug release, and liquid retention properties for better moist wound healing. The dope comprising sodium alginate was extruded into calcium chloride (CaC12) coagulation bath. The developed calcium alginate fibers were then passed through a bath containing hydrolyzed chitosan and dip coated with hyaluronic acid for 24 hours. The resulting ACH composite fibers were then rinsed with deionized water and dried using acetone. These fibers were tested for tensile properties, % swelling, liquid absorption (g/g) and controlled drug release. The results concluded that ACH composite fibers can be produced by wet spinning and have adequate tensile properties, high % swelling, liquid absorption (g/g) and controlled release of hyaluronic acid for improved wound healing.  相似文献   

4.
An ATV-mounted mechanical applicator was designed to treat vineyards with SPLAT-GBM™ for mating disruption of grape berry moth, Paralobesia viteana (Lepidoptera: Tortricidae). SPLAT-GBM was applied to vineyards in 0.8 g drops at a density of 1544 or 3089 drops per hectare for a total of 1.3 or 2.5 kg per hectare. Trials were conducted in 2008 and 2009 in vineyards receiving grower-standard insecticide sprays for control of grape berry moth and other insect pests. In the first trial, SPLAT-GBM applied twice at 1.3 or 2.5 kg/ha caused a significant reduction in grape berry moth infestation at harvest on clusters at the border of the vineyards where infestation is highest, compared with the no-pheromone control, but three applications at 2.5 kg/ha did not result in lower infestation compared with both the control and other treatments. In the second trial, application of SPLAT-GBM 2.5 kg/ha in mid-June and late-July caused a significant reduction in grape berry moth infestation at harvest on clusters at the border of the vineyards. Application in early-May and late-June resulted in infestation that was similar to the other program, but not statistically different from the control. In both trials, there were no significant differences between any of the treatments of SPLAT-GBM and the control inside the vineyards where infestation is low. Among treatments of SPLAT-GBM, infestation was similar regardless of number, rate, or timing of the applications. This study shows that mechanical application of wax matrix drops to release pheromone is an effective method for control of grape berry moth using mating disruption.  相似文献   

5.
Arbuscular mycorrhizal (AM) fungi alleviating the adverse salt effects on growth was tested in bajra (Pennisetum glaucum). Towards this objective we analyzed the photosynthetic activity, proline, phosphatase activity and various antioxidant enzymes such as peroxidase, catalase and superoxide dismutase at 0, 100, 200 and 300 mM salinity levels in AM inoculated and non inoculated bajra plants. Total chlorophyll content was significantly higher in moderate salinity condition in AM fungus (Glomus fasciculatum) inoculated plants, which lead to increase in growth and nutrient uptake capacity of mycorrhizal plants. Antioxidant activity was either increased or decreased due to responses to different salinity stress conditions. Proline accumulation was induced by salt and it was more in shoot of non-AM inoculated plants, but in roots proline accumulation was higher in AM plants at all levels of salinity. This work suggests that the AM fungus helps bajra plants to perform better under moderate salinity levels by enhancing the antioxidant activity and proline accumulation as compared to non-mycorrhizal plants.  相似文献   

6.
Salinity causes a detrimental impact on plant growth,particularly when the stress occurs during germination and early development stages.Barley is one of the most salt-tolerant crops;previously we mapped two quantitative trait loci(QTL) for salinity tolerance during germination on the short arm of chromosome 2 H using a CM72/Gairdner doubled haploid(DH) population.Here,we narrowed down the major QTL to a region of 0.341 or 0.439 Mb containing 9 or 24 candidate genes belonging to 6 or 20 function...  相似文献   

7.
Matrix attachment regions or matrix associated regions (MARs) were special DNA sequences in chromatin of eukaryotic cells that tightly associated with the nuclear matrix or scaffold in vitro after a combination of nuclease digestion and extraction. They were also called scaffold attachment regions (SARs) .  相似文献   

8.
不同种植密度条件下玉米茎秆穿刺强度QTL分析   总被引:1,自引:1,他引:1  
以四287与四144为亲本组配的188个F2:3家系为材料,分别于2013、2014年在2个种植密度下调查茎秆穿刺强度,采用复合区间作图法进行QTL分析,研究玉米茎秆穿刺强度在不同种植密度下的遗传机制。结果表明,在2个种植密度下,共检测到13个与茎秆穿刺强度相关的QTL,分布于玉米的第1、2、3、4、6、7、8、9染色体上,单个QTL可解释3.8%~11.8%的表型变异,位于第6染色体检测到的QTL在所有环境中均能稳定表达。  相似文献   

9.
The development of near-isogenic-lines (NILs) is a very important tool for both genetic and physiological dissection of drought resistance in rice. Two pairs of NILs differing for grain yield under drought stress were isolated and characterized for yield, yield related traits, and several physiological traits in a range of contrasting environments. In replicated field trials both NIL pairs differed significantly for grain yield under drought stress but showed similar yield potential, phenology, and yield component traits under non-stress conditions. A polymorphism analysis study with 491 SSRs revealed that both NIL pairs are at least 96% genetically similar. These NILs show that small genetic differences can cause large difference in grain yield under drought stress in rice. In both pairs the drought-tolerant NILs showed a significantly higher assimilation rate at later stages both under stress and non-stress conditions. They also had a higher transpiration rate under non-stress condition. The most tolerant NIL (IR77298-14-1-2-B-10) had significantly higher transpiration rate and stomatal conductance in severe stress conditions. In one pair the tolerant NIL had constitutively deeper roots than the susceptible NIL. In the second pair, which had higher mean root length than the first pair, the tolerant NIL had more roots, greater root thickness, and greater root dry weight than the susceptible NIL. Deeper root length may allow tolerant NILs to extract more water at deeper soil layers. It is concluded that enhanced rooting depth is an important strategy for dehydration avoidance and rice adaptation to drought stress, but root architecture might not be the only mechanism causing the significant yield increase we observed in lowland drought stress environments. To further dissect the drought avoidance mechanisms in rice, analysis of root hydraulic properties may be necessary.  相似文献   

10.
《Crop Protection》1988,7(1):9-15
In field trials conducted at the National Agricultural Research Centre (NARC) near Islamabad and in farm fields, control of grass weeds including Cynodon dactylon (bermudagrass), Sorghum halepense (johnsongrass), Echinochloa colonum (junglerice) and Dactyloctenium aegyptium (crowfootgrass) increased yields of sunflower by 25–100%. The trials were conducted in the spring (February–May) and kharif (July–October) seasons in 1985 and 1986. Hand weeding generally resulted in the greatest yield response but this method was highly labour intensive and considered to be impractical by local farmers. The average time required to maintain 1 ha weed free in the spring and kharif seasons was 41 and 90 eight-hour man-days, respectively. In three of four trials conducted in the spring season, fluazifop-butyl at 0·25 and 0·5 kg/ha did not provide satisfactory control of grass weeds and did not result in significant increases in sunflower seed yields. The performance of fluazifop-butyl in these trials was adversely affected by hot dry conditions causing severe moisture stress after treatment. In contrast, in the fourth spring trial at NARC in 1986 and in all kharif season trials, fluazifop-butyl at 0·25 kg/ha effectively controlled both annual and perennial grasses and resulted in seed yields comparable to those obtained by hand weeding. Value/cost ratios indicate that, in the spring season under drought stress conditions, application of the herbicide would not be profitable; however, in the kharif season, herbicide treatment to control actively growing grass weeds would provide a cost-effective alternative to hand weeding.  相似文献   

11.
Ionic conductivity and mechanical properties of a mixed polymer matrix consisting of poly(ethylene glycol) (PEG) and cyanoresin type M (CRM) with various lithium salts and plasticizer were examined. The CRM used was a copolymer of cyanoethyl pullulan and cyanoethyl poly(vinyl alcohol) with a molar ratio of 1:1, mixed plasticizer was ethylene carbonate (EC) and propylene carbonate (PC) at a volume ratio of 1:1. The conductive behavior of polymer electrolytes in the temperature range of 298∼338 K was investigated. The PEG/LiClO4 complexes exhibited the highest ionic conductivity of ∼10−5 S/cm at 25°C with the salt concentration of 1.5 M. In addition, the plasticized PEG/LiClO4 complexes exhibited improvement of ionic conductivity. However, their complexes showed decreased mechanical properties. The improvement of ionic conductivity and mechanical properties could be obtained from the polymer electrolytes by using CRM. The highest ionic conductivity of PEG/CRM/LiClO4/(EC-PC) was 5.33×10−4 S/cm at 25°C.  相似文献   

12.
《Plant Production Science》2013,16(3):381-389
Abstract

Scarcity of water and N fertilizer are major constraints to rice production, particularly in developing countries where rainfed upland condition dominates. Improvement of genetic adaptability to inadequate water and N fertilizer is one option to maintain productivity in these regions. NERICAs are expected to yield higher under low input conditions, but growth and yield responses of the cultivars to different ecosystems and N levels remain unknown. The objectives of this study were to characterize the growth and yield performance of NERICAs, in comparison with selected Japanese rice cultivars. The two NERICAs (NERICA 1 and NERICA 5), two Japanese upland cultivars (Toyohatamochi and Yumenohatamochi), and a Japanese lowland cultivar Hitomebore were grown under two ecosystems (irrigated lowland (IL) and rainfed upland (RU)) with two N levels (high (H) and low (L)) for two years. The cultivar difference in the aboveground dry weight and grain yield was the largest in the in RU × L plot, where the values of NERICAs were similar to those in the other plots, but the values of other cultivars were substantially reduced. Regardless of cultivar, N contents of the plants at maturity correlated significantly with the aboveground dry weight at maturity, spikelet number and grain yield per area. These results indicate that NERICAs, compared with the selected Japanese upland cultivars that were bred for drought tolerance, have a higher ability to absorb N under upland conditions, which may contribute to higher biomass production and sink formation, resulting in increased gain yield.  相似文献   

13.
小G蛋白是一类重要的信号转导蛋白,参与植物的各项生命活动,但目前在茶树中的研究尚少。本研究以茶树品种龙井长叶为实验材料,克隆获得1个小G蛋白基因,命名为CsRAC5。序列分析显示,CsRAC5含有597βbp,编码198个氨基酸,具有Rho蛋白的保守结构域;序列多重比对发现,该序列与其他物种序列的一致性高达95.96%。CsRAC5蛋白质的相对分子质量为21.79βkDa,为亲水性蛋白;烟草瞬时表达实验显示,CsRAC5定位于细胞膜和细胞核中。荧光定量PCR结果显示,CsRAC5在茶树中的表达具有明显的组织特异性,其中在叶片中的表达最高,在花粉中的表达最低;低温(4℃)胁迫抑制茶树叶片中CsRAC5的表达。  相似文献   

14.
淹水胁迫下水稻根尖细胞中Ca^2+和Ca^2+—ATP酶的分布   总被引:3,自引:0,他引:3  
应用电镜细胞化学方法,对淹水胁迫下水稻根尖细胞中Ca^2 和Ca^2 -ATP酶分布的变化进行了观察。正常生长条件下,Ca^2 主要分布于液泡和细胞间隙中,而细胞质基质、细胞核中分布很少;Ca^2 -ATP酶主要分布于质膜上,线粒体膜、内质网膜、核膜上也有酶分布。经过没顶淹水处理后,液泡、细胞间隙中的Ca^2 沉淀颗粒明显减少,而胞质及核基质中的沉淀颗粒明显增多,同时,质膜及其他膜结构上Ca^2 -ATP酶的活性明显降低。淹水造成根尖细胞中Ca^2 -ATP酶活性降低,胞质和核基质中Ca^2 积累,将影响细胞的正常生理代谢活动。  相似文献   

15.
Summary Late blight incidence under natural epiphytotic conditions was recorded on 270 potato germplasm accessions for three years. Replication effect was non-significant, whereas genotype and year effects were significant for AUDPC (area under disease progress curve). Disease incidence on the second date of observation (when the control had almost completely blighted) accounted for 85 to 96 percent of the variation in AUDPC. Spearman’s Rank correlation coefficients between AUDPC and disease incidence grades scored on 1–9 and 1–5 scales (on second date of observation) based on the means of three years data were similar to those calculated based on the means of any two years. It is concluded that grading the accessions based on discrete scales at an appropriate single date for two years in a non-replicated trial would be sufficient robust to broadly group accessions into different levels of resistance to late blight. Ten accessions were found to be highly resistant.  相似文献   

16.
Poly (vinyl alcohol) (PVA)/multi walled carbon nanotubes (MWNT) nanocomposite films were fabricated and their microwave absorption behavior were evaluated using vector network analyzer in the frequency range of 8–12 GHz (Xband). The uniform, stable dispersion and well oriented MWNT within the PVA matrix were achieved through using sodium dodecyl sulfate (SDS) as dispersing agent. The surface morphology of the PVA/SDS/MWNT films was examined by scanning electron microscope (SEM). The SEM analysis of the film samples revealed the uniform appearance in the whole surfaces of the fabricated composite films. However, some roughness on the surface was observed due to the presence of MWNT in the film structure. The PVA/SDS/MWNT films show significant increase in microwave absorption which is improved by increasing the MWNT content. The PVA/SDS/MWNT nanocomposite film sample with MWNT loading of 10 wt% showed the maximum and the relatively high microwave absorption of 28.00 dB at the frequency of 8.6 GHz.  相似文献   

17.

Background:

Hypertension is one the most common causes of chronic kidney disease (CKD). One of the major concerns in hypertensive patients is early detection of renal disorders. In the past, serum creatinine (Scr) concentration was used as a marker of kidney function, but it proffers a late reflection of reduced glomerular filtration rate. Cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) have been recently proven to be useful for quantification of CKD. Therefore, we compared the diagnostic value of NGAL with cystatin C and creatinine to evaluate kidney function in hypertensive patients.

Methods:

In this study, 42 hypertensive patients and 30 healthy volunteers were recruited. Serum cystatin C (Scys C) and plasma NGAL were measured using ELISA method. Creatinine, urea, hemoglobin, fibrinogen, and C-reactive protein were measured according to the routine methods. Estimated glomerular filtration rate (eGFR) was considered as the gold standard method (cut-off value of < 78 ml/min/1.73 m2.

Results:

In the patient group, plasma NGAL, cystatin C, and creatinine were all significantly correlated with eGFR, and plasma NGAL correlated best with eGFR. Receiver-operating characteristics analysis indicated that plasma NGAL was a better indicator than creatinine and cystatin C for predicting a GFR < 78 ml/min/1.73 m2. The sensitivity and specificity for NGAL were 96% and 100%, for cystatin C were 92% and 60% and for creatinine were 76% and 47%, respectively.

Conclusion:

Plasma NGAL demonstrated a higher diagnostic value to detect kidney impairment in the early stages of CKD as compared to Scys C and Scr in hypertensive patients.Key Words: Neutrophil gelatinase-associated lipocalin (NGAL), Cystatin C, Creatinine, Hypertension  相似文献   

18.
Heterocyclic monoazo quinazolinone based azo dyes derived by the diazotization of 3-(4-aminophenyl)-2-phenylquinazolin-4(3H)-one with various phenyl pyrazolones based coupling components. All the heterocyclic azo dyes have been characterized by their percentage yield, UV-VIS spectroscopy, elemental analysis, IR spectroscopy, 1H NMR spectroscopy, and dyeing performance on silk, wool, nylon, and polyester fibers. All the dyes gave moderate to excellent fastness properties on each fiber. The main focus was to synthesize heterocyclic monoazo dyes that give good dyeing property along with pharmacological activity (anti bacterial and antifungal). Therefore, the synthesized compounds were examined for their antimicrobial activity at various concentrations using well-known Kirby-Bauer disk diffusion method.  相似文献   

19.
Semi-interpenetrating polymeric network (semi-IPN) hydrogels based on poly(2-hydroxyethyl methacrylate) (PHEMA) and poly(2-hydroxyethyl methacrylate-co-sodium methacrylate) [P(HEMA-co-SMA)], and chitosan with different molecular weights were prepared by crosslinking with ethylene glycol dimethacrylate (EGDMA) and poly(ethylene glycol) diacrylate (PEGDA) and their gelation time, water content, mechanical properties, and morphology were investigated. In consideration of the influence of the molecular weight of chitosan, there is no big difference in the water content, while tensile properties and compressive modulus increased as the molecular weight of chitosan increased. The water content increased and tensile properties and compressive modulus decreased with increasing SMA concentration. Considering the effect of the crosslinking agent, PEGDA had higher water content and lower tensile and compressive moduli than EGDMA. It is suggested that PHEMA/chitosan and P(HEMA-co-SMA)/chitosan semi-IPN hydrogels with different structures and physical properties can be prepared depending on the molecular weight of chitosan, the copolymerization with SMA, and the crosslinking agent type.  相似文献   

20.
Genotype-by-environment interactions (GEI) have been identified as an important component of the genotypic variation for grain and stover yield traits of rabi sorghum varieties and hybrids in India. It has been argued that obtaining an understanding of the causes of these GEI is an important step to identify the scope for genetic improvement of grain and stover yield by conventional breeding. Pattern analysis was used to investigate the regional structure of the GEI for the four traits grain yield, stover yield, days-to-flower, and plant height, measured on the varieties and hybrids tested over 10 years in the All India Coordinated Sorghum Improvement Program (AICSIP). There was evidence that regional differences accounted for part of the GEI for grain yield and days-to-flower but not for stover yield and plant height. Cluster analysis was used to group the locations included in the ACSIP experiments. The five-group level was chosen to examine the causes of GEI among the location groups. Hypotheses were proposed for the observed regional grouping of trials for grain yield. One group of trials consisted of predominantly irrigated trials, the other four groups differed in the timing and intensity of drought stress imposed on the entries. This retrospective analysis provides a basis for testing the hypothesised contributions of environmental variation in water availability to regional GEI for grain and stover yield. If these hypotheses are substantiated, the current multi-environment testing strategy used for the AICSIP trials could be modified to ensure adequate sampling of the five regional groups identified by the retrospective pattern analysis.  相似文献   

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