共查询到19条相似文献，搜索用时 140 毫秒
1.
高效纤维素降解菌短小芽孢杆菌（Bacillus pumilus）T-7的筛选、鉴定及降解能力的研究 总被引：3，自引：0，他引：3
为了得到一株具有降解纤维素性能的产芽孢菌株,采用加热富集芽孢菌及刚果红脱色圈的初筛方法,从菜地土壤、动物粪便、青贮饲料等样品中分离筛选出41株能够降解纤维素的产芽孢细菌。对初筛菌株发酵培养,测定发酵液透明圈直径及纤维素酶活力,菌株T-7具有显著的降解能力,纤维素酶活力达1678.89U/mL。通过形态观察鉴定、生理生化实验和16SrDNA序列分析对其进行种属鉴定,鉴定T-7菌株为短小芽孢杆菌（Bacillus pumilus）。研究了供试菌株T-7的降解工艺,获得了菌株发挥最大降解特性所需的最佳培养条件。结果表明,将菌株T-7以10亿活菌/1Kg的接种量接入玉米秸秆,并且添加辅助碳氮源2%蔗糖+2%尿素时,在发酵8天后对秸秆中纤维素的降解率达40.34%。研究结果为纤维素的生物降解发掘了新的菌种资源,并为秸秆的大规模降解利用奠定了基础。 相似文献
2.
抑制杨树烂皮病高效菌株的筛选及分类地位验证 总被引：2，自引：0，他引：2
为了寻找对杨树烂皮病病原菌具有高效抑制作用的木霉菌株,采用对峙培养法和生长速率法对国内外29个木霉菌株进行了筛选,并对筛选出的高效菌株的生理生态特性和分类地位进行了研究。结果表明：菌株T-33发酵液正丁醇提取物对病原菌菌丝生长的抑制率最高,达到94.2%,对孢子萌发抑制率达到100%。菌株T-33生长最适碳源为葡萄糖,最佳用量为3%(g/L);最适氮源为黄豆粉,最佳用量为0.02%(g/L);培养基最适初始pH 6;最适培养温度25℃。通过18S rDNA测序分析,ITS序列长度是 583 bp,菌株T-33鉴定为Trichoderma viride。 相似文献
3.
湖水中低温菌的筛选及其产酶特性 总被引：1，自引：0，他引：1
为了探索湖水中低温微生物及其酶活的多样性,并获得具有应用价值的低温菌。以低温环境下湖水为样品,通过平板涂布法和划线分离法对其进行初步分离纯化,进一步进行菌落形态、微观形态观察以及生理生化性质的测定,筛选出能够在低温下生长的菌株。并进行蛋白酶、纤维素酶、淀粉酶、木质素酶功能的测定。结果显示共筛选出可培养的低温微生物22 株,包括细菌14 株,真菌5 株,放线菌3株。7 株具有蛋白酶活性,3 株具有淀粉酶活性,6 株具有木质素酶活性,6 株具有纤维素酶活性。其中WF-1 具有四种酶活性,WB-8 具有三种酶活性,其他菌株具有一种或者两种酶活力。筛选的低温菌株具有多种酶活性,具有潜在的开发价值。 相似文献
4.
用稀释分离法从健康辣椒植株的茎、叶、果肉中共分离得到植物内生菌88株,其中细菌有65株,真菌有21株,放线菌2株。用平板对峙法从中筛选出内生菌003和X两株对辣椒疫霉病菌、辣椒绿霉病菌、辣椒炭疽病菌3种病原菌具有明显拮抗作用的菌株,得出抑制率为34.80%～48.0%。根据菌株形态、生理生化特性对菌株003和菌株X进行了初步鉴定,结果显示菌株003和菌株X都为芽孢杆菌属(Bacillus)。 相似文献
5.
辣椒内生菌的分离及拮抗菌的筛选与鉴定 总被引：1，自引：0，他引：1
用稀释分离法从健康辣椒植株的茎、叶、果肉中共分离得到植物内生菌88株,其中细菌有65株,真菌有21株,放线菌2株.用平板对峙法从中筛选出内生菌003和X两株对辣椒疫霉病菌、辣椒绿霉病菌、辣椒炭疽病菌3种病原菌具有明显拮抗作用的菌株,得出抑制率为34.80％～48.0％.根据菌株形态、生理生化特性对菌株003和菌株X进行了初步鉴定,结果显示菌株003和菌株X都为芽孢杆菌属(Bacillus). 相似文献
6.
从连云港海域采集海水、海泥、漂浮物、海洋动物及海洋植物样品,分离得到62株海洋放线菌.采用平板对峙培养法和打孔法测定放线菌不同菌株及其发酵液对9种蔬菜病原真菌的菌丝生长和孢子萌发以及对番茄青枯病菌的抑制作用.结果表明,放线菌菌株BM_2、T-15、T-1-1、D-3、XS-X5-3、M-7和X-7对供试的番茄早疫病菌(Alternaria sola-ni)、茄腐皮镰刀菌(Fusarium solani)、芹菜斑枯病菌(Septoria apii)、番茄枯萎病菌(Fusarium oxysporumf.sp.lycopersici)、番茄叶霉病菌(Fulvia fulva)、番茄灰霉病菌(Botrytis cinerea)、油菜菌核病菌(Scleroti-na sclerotiorum)、辣椒疫霉病菌(Phytophthora capsi-ci)、茄子黄萎病菌(Verticillium dahliae)和番茄青枯病菌(Ralstonia solanacarum)具有明显的抑制作用,同时海洋放线菌的发酵液对番茄早疫病菌分生孢子的萌发具有较强的抑制作用.其中BM-2菌株的抑菌作用最强. 相似文献
7.
为了获得一株产纳豆激酶(NK)活力较强的菌株。以纳豆激酶活力为评价指标,采用紫外线诱变育种的方法和单因素实验方法,确定紫外线诱变剂量,对原始菌株进行诱变育种,并采用纤维蛋白平板法,测定菌株发酵的纳豆激酶活力。试验结果表明,20W紫外灯距离30cm照射240s的诱变,效果较佳。经过诱变及菌种筛选所获得的高产菌株U-5发酵生产的纳豆激酶活力比原始菌株T-3提高了8.81%。经15代传代试验,U-5高效突变株生产的纳豆激酶活力均稳定在5440.37IU/mL以上。 相似文献
8.
五岳寨苏云金芽孢杆菌资源多样性分析及杀虫基因的鉴定 总被引：1，自引：1，他引：0
分离筛选高效广谱野生苏云金芽孢杆菌菌株并对五岳寨地区苏云金芽孢杆菌资源多态性进行分析。采用温度筛选法进行菌株分离筛选,光学显微镜下观测菌株的晶体形态,通过PCR-RFLP和SDS-PAGE法对这些菌株进行基因鉴定和蛋白分析,并进行生物活性测定。从土壤中分离得到72株Bt菌株,共包含13种cry基因,9种基因组合,另有8株未鉴定出基因型,SDS-PAGE蛋白分析发现这些菌株主要表达130、90、50 kDa蛋白;生物活性测定结果显示有20株对小菜蛾和棉铃虫具有高效毒力,另有4株对华北大黑鳃金龟有高效毒力,其中2株的校正死亡率可达80%。五岳寨地区苏云金芽孢杆菌资源丰富并具有良好的多态性。 相似文献
9.
罗晓妙 《农产品加工．学刊》2014,(10)
菌株能在发酵基物上生长良好是发酵食品选择菌株的第一道关卡。以几株形态差异较大的根霉菌为研究对象,在不同碳源、温度、 pH值、光照等条件下培养,观测其生长速度和形态特征,讨论菌株在发酵食品中应用的适应性,为发酵食品的菌株选育和条件控制等奠定基础。结果表明,碳源、温度、 pH值对各菌株均有一定的影响,而光照只对个别菌株有有限的影响。从生长速度来看, R2, R3, R5菌株的最快生长速度明显快于R6;从菌株形态看, R5, R6菌株优于R2, R3菌株。 相似文献
10.
罗晓妙 《农产品加工．学刊》2014,(20):19-22
菌株能在发酵基物上生长良好是发酵食品选择菌株的第一道关卡。以几株形态差异较大的根霉菌为研究对象,在不同碳源、温度、pH值、光照等条件下培养,观测其生长速度和形态特征,讨论菌株在发酵食品中应用的适应性,为发酵食品的菌株选育和条件控制等奠定基础。结果表明,碳源、温度、pH值对各菌株均有一定的影响,而光照只对个别菌株有有限的影响。从生长速度来看,R2,R3,R5菌株的最快生长速度明显快于R6;从菌株形态看,R5,R6菌株优于R2,R3菌株。 相似文献
11.
Genetic analysis of ten quantitative traits related to crop duration in chickpea was carried out using three F
2 sib-populations; 272-2 × CDC Anna, 298T-9 × CDC Anna and 298T-9 × CDC Frontier. F
3 and F
4 families from these populations were further evaluated for traits found important in the initial study. Also, 112 recombinant inbred lines (RILs) of chickpea cross ICCV 2 × JG 62 were evaluated for days to flowering, days to maturity and reproductive period. An analysis of the F
2 population data using the mixed model approach revealed that the additive component of variance was significant for days to flowering, days to first podding and days to first pod maturity, while dominance genetic variance was significant for morphological components of crop duration such as height to first pod and height at flowering. Comparatively high heritability estimates (39–48%) were obtained for days to flowering, days to first pod maturity, percent pod maturity at four months after planting and days to maturity based on offspring-parent (F
4 and F
3 generations) regression and/or analysis of variance for the RIL population. The predicted gain from selection as a percentage of the population mean was low (5% or less) for these key components of crop duration owing to the low variability detected within the populations, the exception being percent pod maturity. To maximize gain from selection in these traits, it is therefore, essential to increase genetic variability among the progenies, potentially through multi-parent crosses that may involve gene introgression from across desi and kabuli types of chickpea and from wild progenitors. 相似文献
12.
以托盘包装冷鲜猪肉馅为研究对象,研究假单胞菌的生长变化与模型构建。结果表明,Gompertz方程拟合获得的假单胞菌生长预测一级模型,相关系数R~2值均大于0.99,偏差因子和准确因子分别为0.870和1.149;采用平方根模型研究温度对假单胞菌生长动力学参数的影响,得到温度与最大比生长速率和延滞期方程分别为:U~(1/2)=0.066×[T-(-11.606)]和(1/t_(LPD))~(1/2)=0.059×[T-(-15.42)],其中T∈[0,20],R~2分别为0.981和0.811,F统计量检验表明方程具有显著性。构建的生长模型能够较好地预测0～20℃下假单胞菌在冷鲜猪肉馅基质上的生长。 相似文献
13.
重组人肿瘤坏死因子TNF-α的克隆与原核表达 总被引：1，自引：1，他引：0
为了构建人肿瘤坏死因子TNF-α与谷胱甘肽-S-转移酶(GST)的融合基因表达载体,并进行原核表达。以人肿瘤坏死因子TNF-α全长转录本为模板,设计特异性引物,经PCR扩增目的基因将其定向克隆到pMD-l8T simple vector中,构建重组质粒pMD-18T-TNFα。然后通过亚克隆将测序正确的TNF-α基因插入表达载体pGEX-4T-1中,筛选出阳性质粒转化宿主菌株BL21(DE3),通过温度、时间等不同条件诱导表达重组蛋白。结果表明,成功克隆到大小为702 bp的TNF-α全长cDNA序列,通过限制性酶切、PCR扩增证实pMD-18T-TNFα和pGEX-4T-1-TNFα载体已构建成功。诱导表达得到约51 kDa重组蛋白GST-TNFα。说明重组蛋白GST-TNFα的表达成功,为进一步获得纯化TNF-α,研究其生物功能、作用机理,制备抗TNF-α单克隆抗体奠定基础。 相似文献
14.
通过对2002年在湖南长沙作一季晚稻和双季晚稻以及在海南三亚冬繁共3次种植的20个优质稻品种60份样品的碾米品质、外观品质和米饭长检测,同时对其中11个品种共33个样品的蒸煮品质化验,分析不同品种在三种环境下种植的各个品质性状的变异系数, 并对20个品种进行聚类分析;按农业部颁布的食用稻品种品质NY/T-593-2002中的籼稻品质指标等级记分标准将11个品种的9个品质性状计算质量指数. 结果显示：不同品种的品质稳定性不同。品质性状的稳定性与品种的质量指数等级有关,在长沙作双季晚稻种植的质量指数达三等的品种,其品质性状相对稳定;在长沙作双季晚稻种植的质量指数达二等的品种,在不适宜环境下质量指数可变为三等甚至四等。不同品质性状的变异系数差异悬殊。各个品质性状的一等至三等达标百分率因品种和环境而变化。 相似文献
15.
Effects of harvest time and low temperature storage on the texture of cabbage leaves 总被引：1，自引：0，他引：1
Mitsuru Taniwaki Masahiro Takahashi Naoki Sakurai Atsushi Takada Masayasu Nagata 《Postharvest Biology and Technology》2009,54(2):106-110
Leaf textures of four cabbage cultivars (T-520, Fuyu-nobori, Satsuki-ou, and Kinkei-201) harvested in winter and spring were evaluated. Acoustic vibration signals generated during penetration of four stacked cabbage leaves were measured using a novel texture measurement system. Texture was quantified using a texture index (TI). The TI of T-520 was higher than that of Fuyu-nobori and continually declined during the entire investigation period (between February and May). However, Fuyu-nobori's TI persisted after early April. This implied that Fuyu-nobori was superior to T-520 in terms of preservation of quality. Satsuki-ou showed either an equivalent or higher TI than T-520 in May. Kinkei-201 had a much lower TI than the other cultivars. TIs of T-520 and Fuyu-nobori stored at a 5 °C for 4 weeks were lower than those of samples without storage. This implied that low temperature storage did not effectively retain the texture quality of the cabbages. 相似文献
16.
为构建灰葡萄孢犬尿氨酸单加氧酶(Bc KMO)基因的原核表达载体并进行高效表达,获得纯化的Bc KMO蛋白。以灰葡萄孢野生型BC22为试材,通过反转录PCR扩增Bc KMO基因,回收Bc KMO基因片段克隆到p MD19-T载体中,测序正确后,酶切p MD19-T-Bc KMO和带有GST标签蛋白的p GEX4T-1质粒,将目的片段进行连接,构建Bc KMO基因的原核表达载体p GEX4T-1-Bc KMO-GST。经酶切和测序鉴定正确后,将构建好的原核载体转化大肠杆菌BL21。经IPTG诱导,在大肠杆菌BL21菌株中成功表达了与GST标签蛋白融合的Bc KMO蛋白,大小约71 k Da。SDS-PAGE分析表明,该蛋白在0.2 mmol/L IPTG诱导12 h时高效表达;Western Blot结果发现目的蛋白能与GST特异性抗体起特异性反应,表明Bc KMO基因的体外诱导表达成功。 相似文献
17.
为了获得纯化的SnRK1.1与FD蛋白,分析蛋白激酶SnRK1.1是否能够磷酸化开花调控途径中的转录因子FD,成功克隆了1 608 bp的SnRK1.1基因以及858 bp的FD与FD-T282A基因,分别与PGEX-4T-3载体连接,获得原核表达载体GST-SnRK1.1、GST-FD和GST-FD-T282A,并分别转化大肠杆菌BL21菌株;SDS-PAGE电泳和考马斯亮蓝染色(CBB)表明,0.5 mmol/L IPTG能够成功诱导出GST-SnRK1.1、GST-FD和GST-FD-T282A蛋白。利用GST纯化介质纯化获得了84 k Da的GST-SnRK1.1蛋白以及58 k Da的GST-FD与GST-FD-T282A融合蛋白;利用体外磷酸化体系证实SnRK1.1能够磷酸化FD,不能磷酸化突变的FD-T282A。研究结果为进一步解析SnRK1.1通过磷酸化转录因子FD参与开花途径调控的机制奠定了良好的基础。 相似文献
18.
The objectives of the study were to estimate the genetic components of variance, predict the response to selection and to evaluate observed response to selection using two populations namely, PSB 7 and PSB 3, of pearl millet (Pennisetum americanum [L.] Leeks). The observed response was studied using four methods of selection based on single and multitrait criteria in three types of families, namely S1, half-sib (HS) and full-sib (FS) families. One hundred SI, HS and FS families each were developed in PSB 7 and PSB 3. Plants within a population were pollinated with bulk pollen of other population to develop HS families. Crosses were made between a pair of plants using one plant from each of the two populations to develop PS families. Data were recorded on days to flower, plant height, tiller number, spike length, spike girth, seed yield per plant and spike weight. Additive genetic variance estimates were significant for all traits. The estimates of dominance and additive × location and dominance × location interaction components were not significant, except additive × location component in PSB 7 for seed yield and spike weight. The genotypic component of variance among S1 families and S1 × location interactions were significant except S1 × location interactions in PSB 7 for days to flower, spike length and spike girth. Twenty-four strains were developed by intermating superior families identified on the basis of four selection methods in each of the six types of families. The selection methods were high seed yield (YS) per se; index selection (IS) for high tiller number and long and thick spike; truncation selection (TS) for high yield among the families having days to flower and plant height lower than the population mean: and visual selection (VS) after completion of flowering for good vigour, uniformity in plant height and good inflorescence attributes. YS and IS were found to be superior to TS and VS with respect to observed genetic gains for seed yield. That advance was higher in selection among SI families as compared with FS and HS families. In general, a good agreement was noted between observed and expected responses. Expected genetic gain from FS reciprocal (R) recurrent selection was higher than the average gain from HS-R selection. 相似文献
19.
Implications of early selection for grain colour on iron and zinc content and productivity of common bean 
下载免费PDF全文
下载免费PDF全文 Rita de Kássia Siqueira Teixeira Dayane Cristina Lima Ângela de Fátima Barbosa Abreu Magno Antonio Patto Ramalho 《Plant Breeding》2015,134(2):193-196
Brazilian consumers prefer beans of the beige grain colour. Common beans help supply dietary requirements for iron and zinc. The objectives of this study were (i) to determine whether early selection for grain colour affects the iron and zinc content and the grain yield in common beans and (ii) if an association between these characteristics was found, to obtain lines of carioca‐type grains with a high iron and zinc content and good grain yield. We evaluated 96 F3:4, F3:5 and F3:6 progeny at two locations for iron and zinc content and grain yield. We selected 48 progeny for grain colour and chose 48 others at random. We found that early selection for grain colour does not affect the zinc content and grain yield. A positive and high association was found between iron and zinc content, and both iron and zinc content were slightly negatively correlated with grain yield. It is possible to obtain common bean lines combining a high iron and zinc content with good grain yield as long as a selection index is used. 相似文献