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1.
根癌农杆菌介导的蓝猪耳遗传转化   总被引:3,自引:0,他引:3  
报道了根癌农杆菌(Agrobacterium tumifaciens)介导的蓝猪耳(Torenia foumieri)遗传转化的方法。筛选蓝猪耳转化芽的最适卡那霉素(Kan)浓度为400mg/L;以稀释10倍的菌液浸染叶盘10~20min,固体共培养基(含20μmol/L乙酰丁香酮)上23℃共培养7~8d可获得转化芽诱导率27.2%;16h光照,8h黑暗是较理想的共培养光周期;茎段作为外植体,其转化芽诱导率要高于叶盘的转化芽诱导率,而且其转化芽比叶盘的转化芽健壮;1/2MS+100mg/L Kan+0.5mg/L IAA是比较理想的生根培养基。实验结果表明,根癌农杆菌介导的蓝猪耳转化获得了抗性再生植株,转化率为24.1%。  相似文献   

2.
对西瓜枯萎病菌(Fusariumoxysporiumf.sp.niveum)的生物学特性测定结果表明:病菌生长温度范围10~35℃,适宜生长温度25~28℃;分生孢子在饱和相对湿度下萌发率为72.6%,在水滴中达85.2%;分生孢子的致死温度为55℃10min;病菌生长的pH值范围在2.38~11.45,最适pH值为6.65~9.69。室内药效测定结果表明:70%代森锰锌300倍,40%灭病威300倍和500倍,25%多菌灵300倍和抗枯灵500倍对枯萎病菌菌丝生长有明显的抑制作用。田间防治以嫁接苗的防治效果最好,达91.2%;其次为15%粉锈宁1000倍和50%DT600倍,防效分别为68.47%和65.05%。  相似文献   

3.
研究表明,适宜钻石玫瑰离体芽诱导分化的培养基为MS 6-BA0.50 mg/L NAA0.10~0.20 mg/L;适宜丛生芽继代增殖的培养基为MS 6-BA1.00 mg/L NAA0.10~0.20 mg/L;适宜试管苗生根的培养基为1/2MS NAA0.10 mg/L,其生根率达90%。  相似文献   

4.
大豆磷酸烯醇式丙酮酸磷酸酯酶(PEPP)研究: Ⅱ.纯化与特性   总被引:1,自引:0,他引:1  
从大豆叶片中分离磷酸烯醇式丙酮酸磷酸酯酶(phosphoenolpyruvate phosphatase,PEPP),通过硫酸胺分部(20%~50%饱和度)沉淀、DEAE-纤维素层析、羟基磷灰石层析将酶纯化了96.81倍,酶活性达17.91U/mg蛋白。该酶专一性较强,米氏常数(Km)为0.39mmol/L(PEP),最适pH6.8,在PH6.O~7.4范围内及50。C以下较稳定,被Mg^2+、Mn^2+激活,F^-、Cu^2+、Zn^2+、PO^3-、MoO4^2-抑制。  相似文献   

5.
高羊茅高频植株再生体系的建立及其影响因子的分析   总被引:12,自引:0,他引:12  
研究了高羊茅(Festuca anmdinacea)愈伤组织诱导培养基和分化培养基组分的最适配比,建立了高羊茅高频再生体系。结果表明,培养基MSM 5mg/L 2,4-D 0.02mg/L KT诱导高羊茅种子出愈率高达92%;愈伤组织可在培养基MSM 4.5mg/L 2,4-D 0.2mg/L KT上长期保持;愈伤组织在培养基MSM 2mg/L 2,4-D 0.2mg/L KT诱导体细胞胚发生后,可在添加2mg/L KT和20mg/L蔗糖的SH培养基(MSH)上诱导分化形成丛生芽,愈伤组织分化率可达96%。再生芽在1/2MS培养基上14d生根率达100%。  相似文献   

6.
田间药效试验结果表明,30%甲维·毒死蜱水乳剂不同剂量对稻飞虱达到防治指标、2~3龄若虫盛期进行防治速效性好,持效期长,药后3~7 d防效达96%~100%,药后10 d对稻飞虱的控制效果仍有88.5%~98.83%,极显著优于对照农药77.5%敌敌畏乳油、20%叶蝉散乳油。30%甲维·毒死蜱水乳剂推荐用量为50 m L/667 m2(制剂用量),防治适期达到防治指标、2~3龄若虫盛期前。  相似文献   

7.
通过对消化体系的选择及双道原子荧光光度计测试条件的优化,建立了氢化物发生-原子荧光光谱法同时测定肥料中砷、汞的方法。方法线性范围宽(As0-100μg/L;Hg0-10μg/L),检出限低(As0.05μg/L和Hg0.07μg/L)。无机肥料中As回收率为98.8%-100.4%,Hg回收率为98.9%-102.2%;有机肥料中As回收率为94.4%-105.6%,Hg回收率为97.6%-103.8%。  相似文献   

8.
不同地区土地沙漠化过程中土壤退化演变规律   总被引:6,自引:0,他引:6  
对不同地区沙漠化土地演变过程与土壤理化性质的相互关系和分异规律进行了研究。结果表明:(1)各地区的沙漠化土地土壤养分含量具有K多.P少,N贫乏的特征;(2)在沙漠化过程中,土壤退化的分异规律与地区分带性有关。其中土壤有机质、速效P、速效K的受损程度为西部区〉中部区〉东部区,全N为中部区(91.49%)〉东部区(67、30%)〉西部区(61.45%),全盐为中部区(52.94%)〉西部区(43.00%)〉东部区(20.00%);(3)速效K和速效P及全盐的分布格局具有明显的地带性特征,其中速效K为西部区(228.8~81.4mg/kg)〉东部区(62.5~32.5mg/kg)〉中部区(40.1~19.2mg/kg),速效P为东部区(7.84~3.45mg/kg)〉中部区(4.84~2.19mg/kg)〉西部区(2.73~0.72mg/kg),全盐为西部区(7.75~1.18g/kg)〉中部区(0.57~0.08g/kg)〉东部区(0.10~0.04g/kg)。土壤盐分与沙漠化关系不明显.而与水环境和人为经营活动有关;(4)从总体上看,土壤机械组成受沙漠化影响的程度为东部区〉中部区〉西部区;其中西部砂粒受损率低于东部、中部.但粉砂高于东部、中部,而粘粒却低于东部、高于中部;(5)中部和东部区砂粒递增高峰期和粉砂与粘粒的递减高峰期(轻度后)均早于西部区(中度后)。在时间序列上中部和东部区受抄漠化危害较西部区早,因此在中部和东部区应重视沙漠化土地的早期防治。  相似文献   

9.
霍山石斛快繁技术筛选研究   总被引:1,自引:0,他引:1  
采用L9(3^4)正交试验设计,对霍山石斛腋茅的增殖培养基进行筛选,研究结果表明,最佳增殖培养基为MS添加6-BA 2~5mg/L、NAA0.5~1.5mg/L、SU 20~30g、CH 0~0.5g/L,且随着增殖继代次数的增加,增殖倍数有加大的趋势。  相似文献   

10.
渝水区位于江西省中部偏西,气候温和(年平均气温16.8~18℃)、日照充足(年平均日照时数1677.4h)、雨量充沛(年平均降雨量1573.6mm)、无霜期长(平均283d),非常适合棉花的生长,是江西省三大棉花主产区之一,常年棉花种植面积7000hm^2左右。棉田土壤主要有黄泥土、黄沙泥土、潮土以及石灰泥土。据土壤测试结果,渝水区棉田土壤有机质含量2%~3%、速效磷(P2O5)含量10~20mg/kg、速效钾(K2O)含量100mg/kg左右、有效硼含量0.18~0.55mg/kg。可见棉田土壤磷、钾养分较缺乏,尤以缺硼严重;  相似文献   

11.
观赏凤梨胚性愈伤组织的诱导、高频再生及超微结构研究   总被引:1,自引:0,他引:1  
以观赏凤梨‘名宝剑’的短缩茎为外植体,研究了不同激素及浓度组合对愈伤组织诱导和植株分化的影响,并通过形态学和组织细胞学观察了不同类型愈伤组织的超微结构和胚性愈伤组织的分化过程。结果表明:NAA对愈伤组织诱导的影响达到极显著水平(P=0.0019),其中0.5mg/L NAA最有利于提高愈伤组织的诱导率和胚性愈伤组织的比...  相似文献   

12.
Principal component analysis (PCA) was applied to the chromatographic and spectroscopic data of authentic Mexican tequilas (n = 14) and commercially available samples purchased in Mexico and Germany (n = 24). The scores scatter plot of the first two principal components (PC) of the anions chloride, nitrate, sulfate, acetate, and oxalate accounting for 78% of the variability allowed a classification between tequilas bottled in Mexico and overseas; however, no discrimination between tequila categories was possible. Mexican products had a significantly (p = 0.0014) lower inorganic anion concentration (range = 1.5-5.1 mg/L; mean = 2.5 mg/L) than the products bottled in the importing countries (range = 3.3-62.6 mg/L; mean = 26.3 mg/L). FTIR allowed a rapid screening of density and ethanol as well as the volatile compounds methanol, ethyl acetate, propanol-1, isobutanol, and 2-/3-methyl-1-butanol using partial least-squares regression (precisions = 5.3-29.3%). Using PCA of the volatile compounds, a differentiation between tequila derived from "100% agave" (Agave tequilana Weber var. azul, Agavaceae) and tequila produced with other fermentable sugars ("mixed"tequila) was possible. The first two PCs describe 89% of the total variability of the data. Methanol and isobutanol influenced the variability in PC1, which led to discrimination. The concentrations of methanol and isobutanol were significantly higher (methanol, p = 0.004; isobutanol, p = 0.005) in the 100% agave (methanol, 297.9 +/- 49.5; isobutanol, 251.3 +/- 34.9) than in the mixed tequilas (methanol, 197.8 +/- 118.5; isobutanol, 151.4 +/- 52.8).  相似文献   

13.
草地贪夜蛾已经对多种杀虫剂产生了严重抗性,为筛选应急防控特效药剂,采用浸叶法研究了国家农业农村部推荐用于草地贪食蛾应急防控药剂清单中的7种不同作用机理杀虫剂对草地贪夜蛾甘肃种群3龄幼虫的室内防效。结果表明,60 g/L乙基多杀菌素悬浮剂2 000倍液、5 000倍液和2%甲维盐乳剂2 000倍液、 4 000倍液处理对草地贪夜蛾3龄幼虫杀虫活性最好,药后24、48 h的校正防效均为100%。其次为0.5%苦参碱水剂300倍液、10%啶虫脒乳油1 000倍液和200 g/L氯虫苯甲酰胺悬浮剂2 000倍液处理,48 h的校正防效分别为82.86%、88.73%、88.57%。生物源农药8 000 IU/uL苏云金杆菌悬浮剂100倍液处理速效性稍差,72 h后校正防效仅为43.28%;4.5%高效氯氰菊酯乳油1 000倍液、1 500倍液处理48 h的校正防效均不足30%,表明草地贪夜蛾可能对该药产生严重的抗性。  相似文献   

14.
Microbial reduction of selenate [Se(VI)] to elemental selenium [Se(0)] is a useful technique for removing Se from agricultural drainage water. A series of batch experiments were conducted in the laboratory to determine the effects of yeast extract (50-1000 mg/L), salinity (EC, 5-75 dS/m), and NO(3)(-) (5-100 mg/L) on the removal of Se(VI) (2000 microg/L) from drainage water by Enterobacter taylorae. Results showed that relatively high amounts of yeast extract (500 mg/L) were needed for E. taylorae to effectively reduce Se(VI) to Se(0). During a 7-day experiment, approximately 95% of added Se(VI) was reduced to Se(0) in the low-salinity drainage water (5 dS/m) with NO(3)(-) values of 5-50 mg/L. In the high-salinity drainage water (50-75 dS/m), reduction of Se(VI) to Se(0) was limited. E. taylorae was also capable of reducing Se(VI) to Se(0) in the San Joaquin Valley drainage water, with a reduction of the added Se(VI) to Se(0) (73.8%) and Se(-II) (20%). This study suggests that E. taylorae may be used to treat Se(VI)-contaminated drainage water in the field.  相似文献   

15.
3'-O-Methyl derivatives of flavan-3-ols, (+)-catechin (C), (-)-epicatechin (EC), and (-)-catechin gallate (CG) were prepared enzymatically. Hexanal (EC and CG family, 5 mmol/L) and conjugated diene (C and EC family, 0.25-10 mmol/L) formation following CuSO4-mediated triacylglycerol-rich lipoprotein oxidation was measured. All EC and CG compounds significantly reduced hexanal formation (p < 0.02). O-Methylation improved the ability of CG (more polar) while reducing the ability of EC (less polar) to limit hexanal formation. 3'-O-methyl EC was 18% (p < 0.001) and 4'-O-methyl 65% (p < 0.001) less able than EC to suppress hexanal formation. At >1 micromol/L all EC and C compounds significantly increased lag time. Parent compounds were more effective (> 4-fold increase) than metabolites (1.5-fold increase). Parent compounds did not influence propagation rate (DeltaOD/min). At >1 mmol/L O-methylated EC and C reduced propagation by 20-40% (p < 0.01). Notably, at 0.25 mmol/L O-methylated EC and C increased propagation rates 22% (p < 0.01) despite prolonging lag time.  相似文献   

16.
Apple peels as a value-added food ingredient   总被引:6,自引:0,他引:6  
There is some evidence that chronic diseases, such as cancer and cardiovascular disease, may occur as a result of oxidative stress. Apple peels have high concentrations of phenolic compounds and may assist in the prevention of chronic diseases. Millions of pounds of waste apple peels are generated in the production of applesauce and canned apples in New York State each year. We proposed that a valuable food ingredient could be made using the peels of these apples if they could be dried and ground to a powder without large losses of phytochemicals. Rome Beauty apple peels were treated with citric acid dips, ascorbic acid dips, and blanches before being oven-dried at 60 degrees C. Only blanching treatments greatly preserved the phenolic compounds, and peels blanched for 10 s had the highest total phenolic content. Rome Beauty apple peels were then blanched for 10 s and dried under various conditions (oven-dried at 40, 60, or 80 degrees C, air-dried, or freeze-dried). The air-dried and freeze-dried apple peels had the highest total phenolic, flavonoid, and anthocyanin contents. On a fresh weight basis, the total phenolic and flavonoid contents of these samples were similar to those of the fresh apple peels. Freeze-dried peels had a lower water activity than air-dried peels on a fresh weight basis. The optimal processing conditions for the ingredient were blanching for 10s and freeze-drying. The process was scaled up, and the apple peel powder ingredient was characterized. The total phenolic content was 3342 +/- 12 mg gallic acid equivalents/100 g dried peels, the flavonoid content was 2299 +/- 52 mg catechin equivalents/100 g dried peels, and the anthocyanin content was 169.7 +/- 1.6 mg cyanidin 3-glucoside equivalents/100 g dried peels. These phytochemical contents were a significantly higher than those of the fresh apple peels if calculated on a fresh weight basis (p < 0.05). The apple peel powder had a total antioxidant activity of 1251 +/- 56 micromol vitamin C equivalents/g, similar to fresh Rome Beauty peels on a fresh weight basis (p > 0.05). One gram of powder had an antioxidant activity equivalent to 220 mg of vitamin C. The freeze-dried apple peels also had a strong antiproliferative effect on HepG(2) liver cancer cells with a median effective dose (EC(50)) of 1.88 +/- 0.01 mg/mL. This was lower than the EC(50) exhibited by the fresh apple peels (p < 0.05). Apple peel powder may be used in a various food products to add phytochemicals and promote good health.  相似文献   

17.
Butterhead lettuce (var. Gloria) were grown in an evaporatively cooled glasshouse using the nutrient film technique (NFT). During the day all plants received a complete nutrient solution (EC 2 dS/m). Treatments were imposed at night and included: complete nutrient solution (control); tap water (EC 0.19 dS/m); and calcium nitrate solutions containing either 100 mg Ca/L (EC 0.80 dS/m), or 200 mg Ca/L (EC 1.45 dS/m).

Tipburn occurred in the control and its incidence was reduced by the other treatments. This effect was associated with an increase in the concentration of calcium in new leaves, except in the water treatment. The night treatments did not affect the fresh weight of mature lettuce.

Circulation of either water or calcium nitrate (100 mg Ca/L) at night may, therefore, be a commercially acceptable means of reducing tipburn losses in lettuce crops grown using hydroponics.  相似文献   

18.
The herbicide norflurazon was encapsulated in ethylcellulose (EC(40)) microspheres by the solvent evaporation technique to obtain controlled release formulations. The kinetics of release of the active ingredient into the aqueous solution from different preparations was determined. It was found that the percentage release of the incorporated herbicide was a function of the composition and formation conditions of the formulations (amount of emulsifying agent, EC(40)/herbicide ratio, stirring speed, and percentage of pore-forming agent). The percentage of the herbicide release was related to the properties of the different microspheres obtained, such as particle size distribution, herbicide loading, or surface morphology. The release percentage depended inversely on the particle size of the microspheres and directly on the content of active ingredient and emulsifying and pore-forming agents. An empirical equation was used to fit the herbicide release data, indicating that the release of norflurazon from the various formulations is controlled by a diffusion mechanism. The time taken for 50% of the active ingredient to be released into water (T(50)) was calculated, showing a wide variation among the different preparations (0.95-16.4 days).  相似文献   

19.
Methanol extracts of various plant parts of Ailanthus altissima were tested against the root knot nematode Meloidogyne javanica . Extracts of bark (ABE), wood (AWE), roots (ARE), and leaves (ALE) from A. altissima were investigated against freshly hatched second-stage juveniles (J(2)). AWE was the most active extract, with EC(50/3d) of 58.9 mg/L, while ALE, ARE, and ABE did not show nematicidal activity. The chemical composition of the extracts of A. altissima was determined by gas chromatography-mass spectrometry, and (E,E)-2,4-decadienal, (E)-2-undecenal, (E)-2-decenal, hexanal, nonanal, and furfural were the most prominent constituents. (E,E)-2,4-Decadienal, (E)-2-decenal, and furfural showed the highest nematicidal activity against M. javanica , with EC(50/1d) = 11.7, 20.43, and 21.79 mg/L, respectively, while the other compounds were inactive at the concentrations tested. The results obtained showed that AWE and its constituents (E,E)-2,4-decadienal and (E)-2-decenal could be considered as potent botanical nematicidal agents.  相似文献   

20.
The content of aroma compounds (dynamic headspace) and catalytic activity of lipoxygenase (LOX) (EC. 1.13.11.12) were analyzed in 15 mm unblanched leek slices seven times during 12 months of frozen storage. The aroma profile changed from consisting of almost only sulfur compounds such as dipropyl disulfide [concentration in fresh leek (FL) = 0.197 mg/L, concentration after 12 months of frozen storage (12M) = 0.0409 mg/L] and propyl (E)-propenyl disulfide (FL = 0.0437 mg/L, 12M = 0.00452 mg/L) in the fresh leeks to being dominated by numerous saturated and unsaturated aldehydes, such as hexanal (FL = 1.53 mg/L, 12M = 3.63 mg/L), (E,E)-2,4-nonadienal (FL = 0.000 mg/L, 12M = 0.0647 mg/L), and (E,E)-2,4-decadienal (FL = 0.129 mg/L, 12M = 0.594 mg/L) at the end of the storage period. The catalytic activity of LOX diminished throughout frozen storage, but approximately 25% of the original activity was present after 12 months of storage.  相似文献   

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