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1.
为探讨淡紫拟青霉E7菌株固体放大发酵因子间的关系以获得大量孢子用于田间试验,通过正交试验设计优化固体发酵培养基成分和培养条件组合,并测定外加碳源、氮源、无机盐和装料方式对产孢量的影响。结果表明:以玉米粉+甘蔗渣+麸皮+壳聚糖组成的正交2号配方为最佳复合培养基质,分生孢子产量达7.13×109个/g,以发酵液pH+液相发酵终点+温度+初始含水量组成的正交4号配方为优适培养条件,分生孢子产量达8.97×109个/g;该菌株在优化后的培养基配方中添加0.4%蔗糖、0.2%蛋白胨、0.002%硫酸锰,以双层纱布袋装料按优化后的培养条件放大培养,产孢量最高可达到8.22×1010个/g。优化后的E7菌株发酵产孢培养基基质用量少,发酵成本低,适合于固体放大发酵生产淡紫拟青霉孢子。  相似文献   

2.
木薯渣固态发酵植酸酶的条件研究   总被引:5,自引:0,他引:5  
木薯渣粗蛋白及无机盐含量较低,与麸皮、米糠混合或同时添加无机氮源及无机盐,可作为发酵培养基合成植酸酶。高浓度的磷抑制植酸酶的合成。最佳发酵条件为:木薯渣为唯一碳原,添加 2% NH4NO3, 0.01% K2HPO4, 0.05% MgSO4·7H2O, 0.05% KCI, 0.01% FeS-O4· 7H2O, 0.9% SDS,培养基水分含量 60%~65%, 10g木薯渣/250 mL三角瓶,接种量为2mL菌悬液(2.8×10个孢子/mL),自然 pH值,培养温度 28~31℃,第8d达产酶高峰,高峰期产酶量为 6730 U/g干曲。   相似文献   

3.
  鉴定了稻瘟病菌孢子萌发过程中分泌产生的蛋白质。将稻瘟病菌菌株2005 50、2005 81未萌发孢子、萌发孢子以及含有孢子萌发液的萌发孢子分别接种后,病情指数分别为11.13, 35.06, 49.01和49.6, 8.4, 62.7;说明孢子萌发液中具有能够帮助稻瘟病菌侵染的物质。利用SDS PAGE电泳分析稻瘟病菌孢子萌发液,发现孢子萌发液中含有蛋白质类物质。进一步利用生物质谱鉴定和数据库资源检索,共检索到8个稻瘟病菌的蛋白质基因,其基因编号分别为MGG_01305,MGG_13188,MGG_12454等。提示这些蛋白质可能在稻瘟病菌侵染过程中具有重要的功能。  相似文献   

4.
稻米糊化温度和直链淀粉含量的简易测定法   总被引:3,自引:0,他引:3  
采用2 mol/L的KOH进行糙米糊化,其糊化温度与标准方法测定结果相比,两者相关系数为0.932,达极显著水平;糊化后直接染色,样品直链淀粉含量与标准方法测定样品直链淀粉含量之间的相关系数为0.915,达极显著水平。该方法具有简便、高效并相对准确的特点,非常适合低世代材料的直链淀粉含量和糊化温度的快速鉴定。  相似文献   

5.
通过提取不同时期玉米秸秆腐解液,研究其对玉米大斑病菌菌丝生长和孢子萌发的影响。利用HPLC检测腐解60 d的腐解液,推测其含有对羟基苯甲酸、邻苯二甲酸、香草酸、丁香酸和苯甲酸。通过外源添加法研究酚酸物质对玉米大斑病菌菌丝生长和孢子萌发的影响,结果表明,5种酚酸物质抑制玉米大斑病菌菌丝生长,抑菌率在14.5%~100%,且随浓度的增加抑制作用趋势增强。苯甲酸和邻苯二甲酸在0.125~1 mg/m L浓度下抑制孢子萌发;羟基苯甲酸在0.062 5~1.0 mg/m L浓度下促进孢子萌发。通过田间调查发现,在开始发病时,秸秆还田抑制玉米大斑病病情指数的发展。  相似文献   

6.
从提高细胞生物量并降低发酵生产成本的目的出发,本文采用单因素试验和正交试验方法,对已筛选出的枯草芽孢杆菌CS27菌株进行液体发酵培养基和工艺条件优化。得到最佳培养基配方为:1.5%黄豆粉、0.5%糖蜜、0.8%氯化铵、1.0%氯化钠、0.1%柠檬酸钠、0.5%碳酸钙、0.1%七水合硫酸镁;最佳发酵条件为:发酵温度32℃,最佳装液量50 mL/250 mL,最适接种量10%,初始pH7.0。在优化后的培养基发酵条件下细胞生物量可以达到1.75×10~9 cfu/mL,为枯草芽孢杆菌CS27菌株规模化生产及应用提供科学依据。  相似文献   

7.
The insecticidal efficacy of the diatomaceous earth formulation SilicoSec® (Agrinova GmbH, Germany) against the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae) was evaluated on peeled rice, paddy rice, maize and barley in laboratory tests. SilicoSec was applied at five dose rates: 0.125, 0.25, 0.5, 1 and 1.5 g/kg of grain. The treated grains were infested with S. oryzae adults, and the weevil mortality was estimated after 24, 48 h, 7 and 14 d of exposure on treated grain. After the 14 d counts, all the exposed adults were removed and progeny production on treated grains was assessed 45 and 90 d later. Insecticidal efficacy of SilicoSec against the rice weevil was highly affected by grain type, exposure interval and dose rate. In all grains tested, longer exposure intervals increased weevil mortality. The efficacy of SilicoSec on maize was not satisfactory, given that after a 14 d exposure at the highest dose rate the mortality did not exceed 65%. Moreover, progeny production on treated maize was high, regardless of the dose rate. On the other hand, 100% of weevils were dead on barley treated with the two highest dose rates of SilicoSec, after a 7 d exposure. However, a complete suppression of progeny production on treated barley was not achieved, even at the highest dose rate. A satisfactory level of protection was recorded on paddy rice treated with 1 and 1.5 g of SilicoSec/kg. At these two rates, all adults were dead after a 7 d exposure, and no progeny were produced during the 90 d incubation period. In contrast, the mortality on peeled rice treated with 1.5 g of SilicoSec/kg did not reach 100%, even after 14 d of exposure, and a high number of progeny were recorded.  相似文献   

8.
田间试验表明,采用"一封一杀"的动态防治模式,以"封闭为主,茎叶喷雾为辅"的防治策略较为符合浙中稻区水稻直播田生产用药实际."一封一杀"是指播后芽前每667 m2用30%丙草胺EC100 mL进行土壤封闭,苗后杂草用300 g/L丙草胺EC100 mL+3%氯氟吡啶酯OD 53.3 mL、13%氰氟·氯氟吡啶酯EC 8...  相似文献   

9.
虫生真菌粉虱拟青霉的培养性状和寄主范围   总被引:5,自引:0,他引:5  
本文详细描述了粉虱拟青霉的形态及在多种培养基上的培养特征,对菌丝生长、产孢、大量培养条件及寄主范围进行了研究,结果表明,该菌在PDA、麦麸汁等培养基上生长速率较快,在察氏、萨氏等培养基上生长缓慢,培养19 d菌落直径分别为40-42 mm,29-35 mm。该菌产孢缓慢,增加光照与添加N源显著促进其产孢。液体扩大培养的最适培养基为10%麦麸+2%蔗糖。固体发酵(稻壳+麦麸)孢子产量较低,为1.6-6亿/克;浅盘静置培养孢子产量则较高,为6.4-30亿/克。该菌可以寄生黑刺粉虱、椰圆蚧和温室白粉虱,不能寄生茶尺蠖、假眼小绿叶蝉、茶橙瘿螨和茶蚜。  相似文献   

10.
To determine biochemical changes during the germination of rice grains (Oryza sativa L. subsp. indica var. Mottaikaruppan) and to improve germination rate using gibberellic acid and surfactants [sodium dodecyl sulfate (SDS) (1.0 g/L) and Triton-X?100 (1.0 mL/L)], whole rice grains soaked in distilled water for 12 h at 30°C were germinated in the dark at 30°C for five days. The highest germination rate (77.1%) was obtained on the 5th day. An increase in the content of reducing sugars from 7.3 to 58.1 mg/g DM (dry matter) was observed from the 1st day of germination. Free amino acids and soluble protein contents increased to 3.69 and 5.29 mg/g DM, respectively on the 5th day of germination. Total protein content decreased from 100.5 to 91.0 g/kg DM during germination. Increases in amylolytic (1.1 to 190.0 U/g DM) and proteolytic (0 to 0.12 U/g DM) activities were observed during germination. Effects of different concentrations of gibberellic acid on the germination of rice grains were evaluated and 0.1 g/L was found to promote germination. When effects of gibberellic acid (0.1 g/L) and surfactants were evaluated individually and together, higher germination rate was observed in the control experiment (grains germinated in distilled water), whereas giberellic acid and surfactants decreased the germination rate. Therefore, the flour obtained from the grains germinated for four days using distilled water to obtain high content of soluble materials and enzyme activities can be used in preparation of bakery items.  相似文献   

11.
以污水源分离菌株Bt BRC-WLY1为供试菌,以啤酒废弃物为培养基,单因素实验优化发酵条件,并探讨补麦芽糖、预处理后的新鲜啤酒酵母液(下称酵母液)和KH2PO4的不同补料成分和补料时间对发酵水平的影响。结果显示,优化的最佳发酵条件是初始pH7.5~8.0、装液量80 mL、发酵温度30 ℃、接种量5%。最佳补料方式为发酵8 h,加入10%的酵母液,与未补料对比,芽胞数、晶体干重、生产强度和单位糖产量分别提高了8、1.78、0.98、3.07倍。  相似文献   

12.
用单孢子接种,分别通过固体平板培养与液体培养,测定氟对分离自黑茶的6株冠突散囊菌和1株黑曲霉生长的抑制率、菌体生长速率和菌丝生物量,研究氟对各菌株生长的影响。结果表明:6株冠突散囊菌在含氟2 000 mg/L、黑曲霉在含氟1 800 mg/L的固体培养基中能生长。100 mg/L剂量的氟对冠突散囊菌生长的抑制率为0.76%~10.24%,对黑曲霉的抑制率达35.71%。随氟浓度的增加,生长速率变小,抑制率增大。液体培养中,100 mg/L的氟对冠突散囊菌与黑曲霉菌丝生物量的抑制率分别为34.47%、80.59%。冠突散囊菌的子囊孢子与黑曲霉的分生孢子对氟具有较强的耐受性,且两种培养方式表明冠突散囊菌比黑曲霉更耐氟。  相似文献   

13.
以橡胶树棒孢霉落叶病病原菌及其产生的粗毒素为供试材料,研究了10种无机盐对多主棒孢菌株菌丝生长、分生孢子萌发的抑制作用和对其粗毒素的钝化作用。结果表明:CuSO4.5H2O、FeCl3和FeSO4.6H2O在2~5mg/mL浓度范围内对多主棒孢病菌菌丝生长及其孢子萌发都有很强抑制作用,菌丝生长抑制率为100%,孢子萌发率为0。KMnO4在0.5~5 mg/mL浓度范围内能够完全抑制孢子的萌发,而1~5 mg/mL浓度范围内却促进菌丝的生长。KMnO4和FeCl3在浓度为0.5 mg/mL时对该毒素均有很强的钝化作用,萎蔫指数分别为2.04%和3.97%。  相似文献   

14.
中草药提取物对香蕉镰刀菌枯萎病病原菌的抑制作用   总被引:5,自引:0,他引:5  
本研究测试了 123 种常见中草药提取物对香蕉镰刀菌枯萎病病原菌的抑菌作用。结果表明,供试提取物 100 倍稀释液对菌株 B1 的菌丝生长和孢子萌发的抑制作用在 50 %以上的分别有 15 种和 14 种;对菌株B2 的菌丝生长和孢子萌发抑制作用在 50 %以上的提取物分别有 7 种和 9 种。进一步测试发现,经过 200 倍 稀释,只有丁香提取物和厚朴提取物对菌株 B1 的菌丝生长和孢子萌发抑制作用均达到 50 %以上。丁香提取物对菌株 B1 和菌株 B2 菌丝生长的抑制中浓度分别为 3 396.31 μg/mL 和 3 375.87 μg/mL。  相似文献   

15.
The effect of acetylation of milled rice grains of selected varieties (TDK 8, YRW 4, Reiziq, Amber 33, and SHZ 2) with varying apparent amylose contents (3.8–26.6%) on their physicochemical properties was investigated. Milled rice samples were treated with different acetic anhydride concentrations (0.004–0.04 g per 100 g of milled rice samples in 225 mL of water). Results showed that glutinous (TDK 8), very low amylose (YRW 4) and low amylose containing varieties (Reiziq) were prone to acetylation even with 0.004 g of acetic anhydride. X-ray diffraction patterns showed an increase in the crystallinity in acetylated samples and formation of V-type crystals, suggesting the possible interaction of acetic anhydride with starch. Acetylation of rice grains resulted in reduced peak and final viscosities and gel strength, particularly in glutinous (TDK 8) and very low amylose (YRW 4) rice. Differential calorimetric study showed that acetic anhydride treatment resulted in reduced thermal transition temperatures and enthalpy of all varieties. Although increase in the retrogradation thermal temperatures was observed, the enthalpy of retrogradation was reduced with increasing acetylation, suggesting that the extent of starch retrogradation was lower in all varieties with more prominent reduction in the glutinous type. Furthermore, the texture of cooked acetic anhydride treated rice grains was less hard and showed more adhesiveness. This study demonstrated that the acetylation of rice grains (instead of flour) was successfully achieved, showing the potential of applying acetylation to alter the textural, pasting, thermal and retrogradation properties of rice.  相似文献   

16.
利用菌丝生长速率法和孢子萌发法研究顶孢霉代谢产物对玉米圆斑病菌生长的抑制能力。结果表明,顶孢霉发酵液对玉米圆斑病菌分生孢子萌发和菌丝生长均有抑制作用。菌丝生长速率测定表明,含有顶孢霉菌代谢产物的培养基(D+P)圆斑病菌菌丝的生长速率低于含有玉米圆斑病菌代谢产物的培养基(Y+P)和空白对照PDA的生长速率,菌丝生长速率分别为65.0、86.5、87.5 mm/d;以Y+P和PDA为对照,D+P对玉米圆斑病菌在第1天和第2天时抑制率最高,均达58%以上;在1 mL PDA体系中,顶孢霉发酵液添加量为0.5 mL时,抑制率可达100%,不同浓度处理间及其与对照处理间顶孢霉发酵液抑制率差异显著(P=0.05);同一处理不同培养天数顶孢霉发酵液抑制率也有显著差异(P=0.05)。孢子萌发实验表明,经顶孢霉发酵液处理后的玉米圆斑孢子萌发率降低,在发酵液浓度为0.9 mL/mL时,萌发率仅为24%,抑制率可达66.67%, EC50约为68 mL/100 mL,且孢子经发酵液处理后产生畸形,不能正常发育。  相似文献   

17.
To obtain a suitable condition for electroporation transformation in indica rice.the 10-day-old immature embryos were selected for optimization experiments.The results showed that one pulse at 850 V/cm,950 μF capacitance,200 μL electreporation buffer with 70 mmol/L sodium glutamate,100 μg/mL plasmid,50 pg/mL carrier DNA,20 embryos per cuvette,0°C treatment and CC medium were the best parameters,which not only jmprovecl the transformation efficiency to 30.89%,but also ameliorated the embryo survival ratio to 95.92%.To further verify the practicability of this condition,the embryes from another indica rice variety and a rice type Ⅱ metallothionein-like gene(OsMT2bL)promoter::mgfp5::gusA construct were tested,and specific GUS expression on the embryos was visualized by histochemical staining.The results showed that the GUS expression on the embryos activated by the OsMT2bL promoter was mainly concentrated on the apical point of the plumule whereas the expression driven by CaMV35S promoter was distributed on nearly all areas of the electroporated tissues.These results indicated that the optimized embryo electroporation conditions could be used not only in genetic transformation of indica rice but also in assay of gene regulation on embryos.  相似文献   

18.
为了探明不同地区的花生网斑病菌致病力和筛选快速稳定的接种方法,以来自山东、云南和辽宁的6个不同地区的花生网斑病菌为材料,用孢子悬浮液对离体叶片和花生植株进行接种,结果表明致病力最强的菌株是WB-SY(分离自辽宁省沈阳市)。最佳接种条件为:开花末期使用高浓度孢子悬浮液(106/mL),接种湿度保持在90%~100%之间持续保湿36h以上,温度在25~28℃之间,接种前黑暗处理24h,接种后近紫光(波长340~380nm)处理。本文筛选出的菌株和快速稳定的接种方法,将为抗病品种的筛选奠定基础。  相似文献   

19.
To obtain a suitable condition for electroporation transformation in indica rice, the 10-day-old immature embryos were selected for optimization experiments. The results showed that one pulse at 850 V/cm, 950 μF capacitance, 200 μL electroporation buffer with 70 mmol/L sodium glutamate, 100 μg/mL plasmid, 50 μg/mL carrier DNA, 20 embryos per cuvette, 0°C treatment and CC medium were the best parameters, which not only improved the transformation efficiency to 30.89%, but also ameliorated the embryo survival ratio to 95.92%. To further verify the practicability of this condition, the embryos from another indica rice variety and a rice type II metallothionein-like gene (OsMT2bL) promoter::mgfp5::gusA construct were tested, and specific GUS expression on the embryos was visualized by histochemical staining. The results showed that the GUS expression on the embryos activated by the OsMT2bL promoter was mainly concentrated on the apical point of the plumule whereas the expression driven by CaMV35S promoter was distributed on nearly all areas of the electroporated tissues. These results indicated that the optimized embryo electroporation conditions could be used not only in genetic transformation of indica rice but also in assay of gene regulation on embryos.  相似文献   

20.
6种药剂防治稻飞虱试验结果表明,呋虫胺20%可湿性粉剂30 g/667 m2、烯啶·吡蚜酮60%水分散粒剂12 g/667 m2、烯啶·吡蚜酮80%水分散粒剂10 g/667 m2对单季晚稻稻飞虱均有不错的防治效果,尤其是对低龄若虫。烯啶·吡蚜酮60%水分散粒剂12 g/667 m2、烯啶·吡蚜酮80%水分散粒剂10 g/667 m2对高龄若虫表现最为突出,速效性好,同时对天敌几乎无影响。吡蚜酮50%可湿性粉剂30 g/667 m2速效性较一般,但持效性较好。吡虫啉10%可湿性粉剂50 g/667 m2的防效较差,对高龄若虫几乎不起作用。毒死蜱40%水乳剂100 mL/667 m2加氟啶虫胺腈22%悬浮剂14 mL/667 m2速效性一般,持效性较差,却对天敌影响较大。以六(4)代褐飞虱为主的稻田为例,需掌握低龄若虫或卵孵高峰期,科学选用吡蚜酮50%可湿性粉剂、呋虫胺20%可湿性粉剂、烯啶·吡蚜酮60%水分散粒剂、烯啶·吡蚜酮80%水分散粒剂进行轮换防治。  相似文献   

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