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Early Growth and Development of Horseweed (<i>Conyza canadensis</i>(L.) Cronq.) 预览
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作者 William T. Molin Katherine Parys Christine L. Beck 《美国植物学期刊(英文)》 2020年第1期40-50,共11页
Horseweed (Conyza canadensis (L.) Cronq.) produces thousands of small elongated seeds which are botanically defined as achenes;yet, relative to the quantity of achenes produced, few seedlings survive to produce mature... Horseweed (Conyza canadensis (L.) Cronq.) produces thousands of small elongated seeds which are botanically defined as achenes;yet, relative to the quantity of achenes produced, few seedlings survive to produce mature plants. The developmental progression from achene to 4 mm seedlings was documented, and seedling response to moisture deprivation was described. Radical protrusion through the pericarp occurred between 18 and 30 hours after onset of imbibition in water or when germinated on soil at or greater than field capacity. A ring of root hair initials formed immediately after radical emergence at the interface of what was to become the separation between the root and hypocotyl. By 48 hours post imbibition, radicals differentiated into a distinct root with root cap and a hypocotyl, and root hairs elongated. By 72 hours post imbibition, seedlings had emerged from the pericarp, and had: expanded photosynthetic cotyledons, a clearly defined hypocotyl, a ring of elongated root hairs exceeding 1 mm in length, and a root equal or longer than the hypocotyl. The epicotyl had not yet emerged, and the total seedling length was approximately 3 to 4 mm. Germination was delayed on soil at or below field capacity. More than 95% of two- and four-day-old seedlings that had been desiccated for more than 24 hours died after being rehydrated. 展开更多
关键词 Horseweed Conyza CANADENSIS GERMINATION
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基质和温度及乙烯利对滇青冈种子发芽的影响 预览
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作者 彭思华 叶桂荣 +13 位作者 李莲芳 王慷林 凌莉芳 高誉衡 张青青 杨永洁 沈松 杨历雨 吴俊多 王凯 付志高 郑川玲 刘进 杨博 《种子》 北大核心 2020年第2期32-36,43,共6页
采用L 9(34)正交试验开展基质、温度及乙烯利浸种对滇青冈种子发芽影响的试验。结果表明,滇青冈种子发芽延续期98 d,处理组合的平均发芽率、发芽势、发芽指数和发芽速度分别为48.7%~76.2%、4.9%~16.4%、2.1~3.7粒·d-1和92~105 d,... 采用L 9(34)正交试验开展基质、温度及乙烯利浸种对滇青冈种子发芽影响的试验。结果表明,滇青冈种子发芽延续期98 d,处理组合的平均发芽率、发芽势、发芽指数和发芽速度分别为48.7%~76.2%、4.9%~16.4%、2.1~3.7粒·d-1和92~105 d,处理组合间4指标差异均达到显著和极显著水平(p<0.05或p<0.01)。基质是影响以上4个指标的主导因子,其中,森林土∶炭渣为60%∶40%的配比极显著地提高滇青冈种子发芽相关指标,35℃温度处理显著地提高滇青冈种子的发芽速度。发芽率和发芽势理论优水平组合为1.2%的乙烯利浸种置于25℃烘箱恒温处理3 h,播种于森林土∶炭渣为60%∶40%的基质中。 展开更多
关键词 滇青冈 正交试验 基质 温度 乙烯利 发芽
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黑豆添加微量元素发芽后对雌性大鼠更年期综合征的影响 预览
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作者 王笑 田晨颖 +4 位作者 吴明泽 李圆圆 孙志强 高鹏 代龙 《食品工业科技》 CAS 北大核心 2020年第3期297-301,307,共6页
目的:通过添加微量元素发芽提高黑豆的营养价值,并对黑豆添加微量元素发芽后对雌性大鼠更年期综合征的影响进行研究。方法:以健康雌性SD(Sprague-Dawley,SD)大鼠为实验动物,制备摘除卵巢的大鼠动物模型(去势动物模型),随机分成7组,即正... 目的:通过添加微量元素发芽提高黑豆的营养价值,并对黑豆添加微量元素发芽后对雌性大鼠更年期综合征的影响进行研究。方法:以健康雌性SD(Sprague-Dawley,SD)大鼠为实验动物,制备摘除卵巢的大鼠动物模型(去势动物模型),随机分成7组,即正常组、模型组、阳性药组、生豆组、清水发芽组、富微低组、富微高组,分别给药,考察黑豆添加微量元素发芽后对摘除卵巢的雌性大鼠生殖内分泌的影响。结果:与正常组相比,模型组的阴道角化上皮细胞含量极显著降低86%(P<0.01),白细胞含量极显著升高1233%(P<0.01),上皮细胞含量极显著降低96%(P<0.01),雌二醇(Estradiol,E2)显著降低68%(P<0.05),卵泡刺激素(Follicle stimulating hormone,FSH)显著升高28%(P<0.05),成功建立模型。与模型组相比,生豆组、清水组、富微高组、富微低组都能极显著升高角化上皮细胞含量281%、362%、455%、466%(P<0.01);生豆组与模型组相比E2极显著升高85%(P<0.01),FSH显著降低12%(P<0.05)。富微高组、富微低组与模型组相比FSH分别显著降低10%、14%(P<0.05);与模型组相比,富微高组与富微低组子宫内膜厚度明显增厚,腺体数量增多,病理性增生减少,炎性浸润减轻。与生豆组相比,清水组、富微低组、富微高组均能显著升高角化上皮细胞含量21%、46%、48%(P<0.05)。与清水组相比,富微低组、富微高组均能显著升高角化上皮细胞含量19%、22%(P<0.05)。富微高组与富微低组比角化上皮细胞含量没有显著性差异。结论:黑豆添加微量元素发芽后对角化上皮细胞含量有极显著的升高作用,能在一定程度上综合改善雌性大鼠更年期综合征症状。 展开更多
关键词 黑豆 微量元素 发芽 更年期综合征
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不同种衣剂配方对达乌里胡枝子种子萌发的影响 预览
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作者 王娟 张亚妮 +4 位作者 熊乙 原黎明 周亚楠 赵祥 佟莉蓉 《草地学报》 CAS CSCD 北大核心 2020年第1期237-244,共8页
为筛选出适宜的达乌里胡枝子(Lespedeza daurica)种衣剂配方,从而为达乌里胡枝子种衣剂的利用提供参考,进而解决达乌里胡枝子在推广种植上受限制的问题。试验材料为‘晋农一号’达乌里胡枝子(L.daurica‘Jinnong No.1’,简称LD),选用聚... 为筛选出适宜的达乌里胡枝子(Lespedeza daurica)种衣剂配方,从而为达乌里胡枝子种衣剂的利用提供参考,进而解决达乌里胡枝子在推广种植上受限制的问题。试验材料为‘晋农一号’达乌里胡枝子(L.daurica‘Jinnong No.1’,简称LD),选用聚乙烯醇、高吸水性树脂、根瘤菌(Rhizobium)、硅藻土和膨润土对LD种子进行包衣(包衣剂与种子的质量比分别为1∶1和2∶1),研究不同配方种衣剂对LD种子质量和萌发特性的影响。试验结果表明:4%的聚乙烯醇具有成膜性和粘结性,较低的水溶性和脱落率;5%的高吸水性树脂可以提高种子活力和萌发特性;膨润土与硅藻土按1∶4的质量比混合最佳。药种比为1∶1时发芽率和活力指数均显著提高。故LD种衣剂药种比的最佳配比为1∶1,配方为:根瘤菌菌剂100 g·kg-1、黏着剂300 mL·kg-1、保水剂50 g·kg-1、硅藻土440 g·kg-1和膨润土110 g·kg-1。 展开更多
关键词 达乌里胡枝子 种子丸衣化 种衣剂 种子活力 萌发
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大豆萌发期脂肪氧化酶与脲酶活性变化及钝化方法效果评价 预览
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作者 邢竺静 李笑梅 +4 位作者 赵廉诚 石彦国 王如梦 闫怡宏 张娜 《食品研究与开发》 CAS 北大核心 2020年第1期14-19,共6页
为探究大豆萌发期抗营养因子含量变化规律及钝化方式,以黑龙江地区的黑科56、黑农71为原料,测定此两种萌发大豆在不同萌发时间阶段中脂肪氧化酶和脲酶两种抗营养因子的活性变化,并在萌发20 h酶活性至最低时,分别以烘烤、微波、沸水漂烫... 为探究大豆萌发期抗营养因子含量变化规律及钝化方式,以黑龙江地区的黑科56、黑农71为原料,测定此两种萌发大豆在不同萌发时间阶段中脂肪氧化酶和脲酶两种抗营养因子的活性变化,并在萌发20 h酶活性至最低时,分别以烘烤、微波、沸水漂烫3种方法处理萌发豆,比较对脂肪氧化酶与脲酶的钝化效果,筛选出适宜的钝化方式并确定其工艺参数。结果表明,萌发20 h黑科56与黑农71脂肪氧化酶活性分别为100.8 U和99 U,脲酶活性分别为4.73 U/g和4.82 U/g;钝化方式效果最佳为沸水漂烫,其工艺参数为:沸水漂烫40 s,两个品种与未漂烫的大豆相比,脂肪氧化酶活性均降低至10.9 U;脲酶活性分别降低至0.18 U/g(黑科56)和0.13 U/g(黑农71)。通过顶空固相微萃取-气相色谱-质谱联用法对钝化后的两种萌发大豆主要豆腥味物质进行了定性、定量分析,且得出脂肪氧化酶活性与豆腥味物质含量呈极显著正相关。 展开更多
关键词 大豆 萌发 脂肪氧化酶 脲酶 钝化
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Proof of homothally of P heopolykrikos hartmannii and details of cyst germination process 预览
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作者 CHAI Zhaoyang HU Zhangxi +1 位作者 LIU Yuyang TANG Yingzhong 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2020年第1期114-123,共10页
Resting cysts play crucial roles in the ecology of dinoflagellates,especially in wintering or surviving unfavorable conditions,seeding harmful algal blooms(HABs),and facilitating the geographic expansion.Encystment of... Resting cysts play crucial roles in the ecology of dinoflagellates,especially in wintering or surviving unfavorable conditions,seeding harmful algal blooms(HABs),and facilitating the geographic expansion.Encystment of dinoflagellates is tightly coupled with sexual reproduction in most cases,which can occur either through homothallism(self-fertilization)or heterothallism(intercrossing of+/-strains).The types of sexual reproduction have important ecological implications.The toxic and HAB-forming dinoflagellate,Pheopolykrikoides hartmannii has been previously reported to be heterothallic.Here,we provide visual confirmation of homothally of P.hartmannii and the first detailed visual recording of cyst germination based on the observations of a clonal isolate from Jiaozhou Bay,China.To document the homothallism,we first observed cell pairs in sexual mating,planozygotes with two longitudinal flagella,and cysts with typical morphology as described previously from the clonal culture.We then germinated a single cyst,established a new clonal culture from one of the two daughter cells after the first cell division of the germling(i.e.from the diploid germling to two haploid cells),and produced cysts again from the newly established clonal culture.For the observation of the germination time-series,we took micrographs and videos to show all germination processes,particularly with an interesting observation of the short amoeboid stage of the germling releasing from the archeopyle(~15 s),which was a landmark of the germination process and has not been reported elsewhere.This definitive evidence of homothallic sexuality and cyst production in P.hartmannii provides a new insight into the biology and ecology of the species,particularly a mechanism that may partly account for the population dynamics and ubiquitous distribution of the species. 展开更多
关键词 GERMINATION harmful ALGAL BLOOMS (HABs) heterothallism homothallism RESTING CYST Pheopolykrikos hartmannii
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温度和露时对荔枝霜疫霉侵染发病的影响 预览
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作者 张荣 徐丹丹 +4 位作者 姜焰鸣 江立群 习平根 陈厚彬 姜子德 《华南农业大学学报》 CAS CSCD 北大核心 2020年第2期88-94,共7页
【目的】研究不同温度和露时条件下荔枝霜疫霉Peronophythora litchi病菌孢子囊的萌发和侵染动态,并以此为变量构建数学模型,以期为病害精准预测预报及防控提供参考和依据。【方法】在人工控温、控湿条件下,研究温度(15~30℃)和露时(2~2... 【目的】研究不同温度和露时条件下荔枝霜疫霉Peronophythora litchi病菌孢子囊的萌发和侵染动态,并以此为变量构建数学模型,以期为病害精准预测预报及防控提供参考和依据。【方法】在人工控温、控湿条件下,研究温度(15~30℃)和露时(2~24 h)对荔枝霜疫霉孢子囊萌发和侵染的影响;选用韦布尔模型的修正式,在SAS软件中拟合得到准确度较好的孢子囊萌发和发病严重度模型,进而绘制其对应的等高线风险预测图。【结果】温度、露时及其交互作用可显著影响荔枝霜疫霉孢子囊的萌发及寄主发病的严重度。荔枝霜疫霉孢子囊萌发率和寄主发病严重度随着露时的延长而逐渐升高。在温度为25℃时,所有露时处理条件下的孢子囊萌发率达到最高;露时相同的条件下,当温度为25℃时,孢子囊侵染荔枝果实发病严重度最强。当温度为22~30℃、露时为3~24 h时,叶片的病害严重度超过0.2;孢子囊侵染果实发病迅速且严重,当温度为15~30℃、露时约2~3 h时,果实发病的严重度高于0.6。荔枝霜疫霉侵染叶片和果实发病严重度模型分别为f(t,θ)={1−exp[−(0.1943×t)2]}/cosh[(θ−27.7696)×0.9277/2]和f(t,θ)={1−exp[−(0.4693×t)2]}/cosh[(θ−24.556)×0.1709/2]。【结论】荔枝霜疫病发生依赖于温度和露时,本研究建立的模型可以用于指导生产上防治该病害的施药时间和次数。 展开更多
关键词 温度 露时 荔枝霜疫霉 孢子囊 萌发 侵染 模型
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发芽条件对西兰花芽苗菜总黄酮富集的影响 预览
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作者 柏夏琼 陈介南 +1 位作者 张林 詹鹏 《食品研究与开发》 CAS 北大核心 2020年第1期105-110,共6页
为富集西兰花芽苗菜总黄酮,研究不同消毒方法(物理消毒、物理化学联合法)对西兰花种子消毒效果的影响以及不同培养条件下总黄酮含量的变化。以西兰花种子为试材,通过单因素试验(浸泡温度、浸泡时间、发芽温度、发芽时间)与正交试验对发... 为富集西兰花芽苗菜总黄酮,研究不同消毒方法(物理消毒、物理化学联合法)对西兰花种子消毒效果的影响以及不同培养条件下总黄酮含量的变化。以西兰花种子为试材,通过单因素试验(浸泡温度、浸泡时间、发芽温度、发芽时间)与正交试验对发芽条件进行优化。结果表明,紫外消毒10 min联合1%食品级奥克泰士D10消毒效果好,发芽率最高;西兰花富集总黄酮的最适发芽条件为:浸泡温度25℃、浸泡时间6 h、发芽温度20℃、发芽时间4 d。在最佳工艺条件下,西兰花芽苗总黄酮含量为11.33 mg/g。 展开更多
关键词 西兰花 消毒 总黄酮 富集 发芽
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多花黄精种子萌发过程的形态和解剖研究 预览
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作者 陈怡 柳雪晨 +2 位作者 陈松树 刘红昌 赵致 《种子》 北大核心 2020年第2期5-10,共6页
为解除多花黄精种子休眠、促进种子萌发,利用Nikon-SMZ 800体式显微镜观察多花黄精种子不同萌发时期的外观形态,采用石蜡切片法将多花黄精种子特殊部位制成切片,在Olympus-BX 61光学显微镜下观察其解剖结构,探究多花黄精种子萌发过程中... 为解除多花黄精种子休眠、促进种子萌发,利用Nikon-SMZ 800体式显微镜观察多花黄精种子不同萌发时期的外观形态,采用石蜡切片法将多花黄精种子特殊部位制成切片,在Olympus-BX 61光学显微镜下观察其解剖结构,探究多花黄精种子萌发过程中的形态变化及解剖特征。结果表明,1)多花黄精种子萌发过程可分为:刚采摘、未萌发、刚萌发、小球茎形成、初生根茎形成和出苗6个阶段;2)成熟的多花黄精种子,其胚未分化出明显的子叶、胚芽和胚根,随着种子的萌发而分化成成熟胚;3)多花黄精种子的萌发伴随着胚乳的降解;4)多花黄精种子同时存在生理休眠和形态休眠,具有形态生理休眠特性。 展开更多
关键词 多花黄精 种子 萌发 形态 解剖
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干旱胁迫下几种岩溶区适生灌木种子的萌发特性研究及抗旱性评价 预览
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作者 姚娜 史静 +2 位作者 邓素媛 丘金花 蒋玉秀 《草学》 2020年第1期19-25,共7页
为了筛选抗旱性能好的岩溶区适生灌木品种,本试验采用不同浓度梯度的PEG-6000溶液对5种岩溶区常见灌木种子进行了模拟干旱胁迫研究,结果表明,翅荚决明随着干旱胁迫的强度增加各项指标逐渐降低,但在高浓度胁迫时,仍然有顽强的发芽势;圆... 为了筛选抗旱性能好的岩溶区适生灌木品种,本试验采用不同浓度梯度的PEG-6000溶液对5种岩溶区常见灌木种子进行了模拟干旱胁迫研究,结果表明,翅荚决明随着干旱胁迫的强度增加各项指标逐渐降低,但在高浓度胁迫时,仍然有顽强的发芽势;圆叶舞草在PEG溶液低浓度胁迫时各指标高于对照,说明轻度的干旱胁迫对种子萌发具有促进作用;通过隶属函数对各相对指标综合分析来看,5种灌木种子抗旱性能从高到低依次为:翅荚决明>圆叶舞草>合萌>木豆>多花木兰。 展开更多
关键词 岩溶区 灌木 干旱胁迫 萌发 抗旱性
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镉离子胁迫下钙镁离子对水稻种子萌发期耐镉性的影响 预览
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作者 滕浪 何腾兵 +4 位作者 付天岭 李相楹 陈柏原 曾庆庆 陈贵平 《种子》 北大核心 2020年第1期18-25,共8页
以西南地区主栽水稻品种Q优6号为材料,采用温室发芽试验,研究Cd^2+胁迫下Ca^2+、Mg^2+对水稻发芽率、生长量及根芽中镉含量的影响。结果表明:在1 mg·kg-1 Cd 2+浓度(简称1 Cd)胁迫下,随着Ca^2+浓度的增加,水稻发芽率、发芽指数逐... 以西南地区主栽水稻品种Q优6号为材料,采用温室发芽试验,研究Cd^2+胁迫下Ca^2+、Mg^2+对水稻发芽率、生长量及根芽中镉含量的影响。结果表明:在1 mg·kg-1 Cd 2+浓度(简称1 Cd)胁迫下,随着Ca^2+浓度的增加,水稻发芽率、发芽指数逐渐增加,随着Mg^2+浓度的增加,水稻发芽率、发芽指数逐渐降低;在2 mg·kg^-1 Cd^2+浓度(简称2 Cd)胁迫下,Ca 2+使水稻发芽率、发芽指数均提高22.53%,随着Mg^2+浓度的增加,水稻发芽率、发芽指数先降低后增加。在1 Cd胁迫下,随着Ca^2+浓度的增加,水稻生物量逐渐增加,在2 Cd胁迫下,随着Ca^2+浓度的增加,水稻生物量逐渐降低;在1 Cd胁迫下,Mg^2+对水稻生物量生长的强弱关系为1 Cd+3 Mg>1 Cd+1 Mg>1 Cd+2 Mg;在2 Cd胁迫下,随着Mg 2+浓度的增加,水稻生物量逐渐增加。在1 Cd胁迫下,随着Ca^2+、Mg^2+浓度的增加水稻根系中Cd的含量先增加后降低,水稻芽中Cd含量均呈降低趋势;在2 Cd胁迫下,水稻根芽中Cd的含量均随着Ca^2+、Mg^2+浓度的增加而降低。因此,Cd^2+胁迫下添加Ca^2+、Mg^2+能够增加水稻发芽率、发芽指数、活力指数,增强水稻种子萌发期生物量与生长量,降低根系与芽中Cd的含量。 展开更多
关键词 钙、镁离子 镉胁迫 水稻 萌发期 耐镉性
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风选和引发处理对甜椒种子萌发及幼苗生长的影响 预览
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作者 季延海 吴萍 +3 位作者 王晨 钟启文 武占会 刘明池 《中国瓜菜》 CAS 北大核心 2020年第1期29-32,共4页
以甜椒种子为试材,通过风选和硝酸钾引发的方式,研究对甜椒种子萌发和幼苗生长的影响。试验设置1%硝酸钾溶液20℃下分别引发5、6、7 d,以未引发种子为对照,研究不同引发时间对甜椒种子萌发和幼苗生长的影响。结果表明,风选后甜椒种子千... 以甜椒种子为试材,通过风选和硝酸钾引发的方式,研究对甜椒种子萌发和幼苗生长的影响。试验设置1%硝酸钾溶液20℃下分别引发5、6、7 d,以未引发种子为对照,研究不同引发时间对甜椒种子萌发和幼苗生长的影响。结果表明,风选后甜椒种子千粒重较原种子显著增加3.25%,较不合格种子显著增加135.56%,不合格种子发芽势较CK处理显著降低43.42%,优选种子发芽率较CK处理显著提高5%。实验室发芽试验表明,发芽势各处理较CK处理显著提高58.49%、52.83%%、60.38%;发芽畸形数量各处理较CK处理显著降低73.91%、73.91%、69.57%;发芽指数各处理较CK处理显著提高了76.28%、69.87%、78.21%。穴盘育苗幼苗试验表明,在播种后47 d株高较CK处理显著提高13.21%,茎粗显著提高10.29%,叶片数显著提高9.09%,壮苗指数显著增加17.65%。综上可得,风选处理后,选用1%硝酸钾溶液,在20℃条件下,引发处理7 d能够显著提高发芽率和发芽势,促进幼苗生长,提高壮苗指数。 展开更多
关键词 甜椒 风选 引发 萌发
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铅(Pb^2+)和镉(Cd^2+)对火炬树种子萌发及幼苗生长的影响 预览
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作者 曲同宝 杨塍希 +1 位作者 马文育 王影 《中南林业科技大学学报》 CAS CSCD 北大核心 2020年第1期30-36,共7页
【目的】研究不同浓度重金属铅(Pb^2+)和镉(Cd^2+)对火炬树Rhus typhina种子萌发及幼苗生长的影响,探索火炬树对重金属铅、镉胁迫的耐受程度及机理。【方法】采用培养皿滤纸发芽法,分别用不同浓度Pb^2+(300、600、900、1200、1500 mmol... 【目的】研究不同浓度重金属铅(Pb^2+)和镉(Cd^2+)对火炬树Rhus typhina种子萌发及幼苗生长的影响,探索火炬树对重金属铅、镉胁迫的耐受程度及机理。【方法】采用培养皿滤纸发芽法,分别用不同浓度Pb^2+(300、600、900、1200、1500 mmol/L)、Cd^2+(140、280、420、560、700 mmol/L)溶液处理火炬树种子,测定种子发芽率、发芽指数、幼苗胚根长和茎长、硫代巴比妥酸(TBARS)含量、可溶性蛋白含量、超氧化物歧化酶(SOD)活性及过氧化物酶(POD)活性。【结果】与对照相比,不同浓度Pb^2+、Cd^2+均对火炬树种子的发芽率、发芽指数和幼苗生长有抑制作用,但低浓度Pb^2+可促进根长和芽长的伸长。随着Pb^2+和Cd^2+溶液浓度的增加,幼苗叶片中SOD活性和可溶性蛋白含量表现为先增加后降低,POD活性和TBARS含量均逐渐升高。其中,Cd^2+浓度为700 mmol/L时,发芽率、发芽指数、芽长和SOD活性达到最低值,而TBARS含量最高;Pb^2+浓度为1500 mmol/L时,根长达到最低值,POD活性达到最高值;Pb^2+浓度为600 mmol/L时,可溶性蛋白含量最高。【结论】Pb^2+浓度为300 mmol/L时会抑制火炬树种子萌发,但会促进幼苗生长,其余浓度Pb^2+、Cd^2+胁迫下,火炬树种子与幼苗受到一定影响,但是均较好完成了萌发与幼苗生长,并表现出多种积极的适应性特征,未出现无根苗现象,火炬树较其他木本植物对铅、镉2种重金属表现出更强的耐性。本试验结果可为今后选用火炬树作为重金属污染土壤的植物修复材料提供理论参考。 展开更多
关键词 火炬树 重金属 种子萌发 生理反应 幼苗生长
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Role of the Putative Polysaccharide Deacetylase BA1836 from <i>B. anthracis</i>in Spore Development and Germination 预览
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作者 Anastasia Tomatsidou Dimitris Koutsioulis +3 位作者 Dimitris Tzamarias Michael Kokkinidis Waldemar Vollmer Vassilis Bouriotis 《微生物学(英文)》 2019年第8期679-702,共24页
Putative and known polysaccharide deacetylases (PDAs) from B. anthracis have key roles in resistance to host lysozyme, stabilization of the cell wall, biogenesis of peptidoglycan (PG) and for neutral polysaccharide mo... Putative and known polysaccharide deacetylases (PDAs) from B. anthracis have key roles in resistance to host lysozyme, stabilization of the cell wall, biogenesis of peptidoglycan (PG) and for neutral polysaccharide modification and attachment to PG. Here we elucidated the physiological role of the putative PDA BA1836 from B. anthracis. The ba1836 gene was expressed upon entrance into the stationary phase of growth and enhanced during the early stages of sporulation. The Δba1836 knockout strain had normal growth rate, did not exhibit any significant alterations in PG pattern of stationary phase cells and was not sensitive to lysozyme, but showed a defect in cell separation. Strikingly, the Δba1836 mutant strain exhibited a severe delay in spore development although mature spores were ultimately developed and had normal morphology. Additionally, digestion of Δba1836 mutant spore PG with mutanolysin produced an almost identical muropeptide pattern compared to peptidoglycan from wild type spores, although the amount of all muropeptides was significantly reduced. Finally, knockout spores exhibited a lower germination rate. To our knowledge, BA1836 has a unique role, among the presently characterized PDAs from B. anthracis, in spore development and germination. 展开更多
关键词 Bacillus ANTHRACIS POLYSACCHARIDE DEACETYLASES BA1836 Spores GERMINATION Spore Development
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Isolation and Characterization of Endophytic Fungi from Purslane and the Effects of Isolates on the Growth of the Host 预览
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作者 Mandlaa   +5 位作者 Yu Zhang Yongqing Wan Ying Tie Bo Zhang Ruigang Wang Guangxia Wang 《微生物学(英文)》 2019年第5期438-453,共16页
Purslane, a common weed, has been used as food or folk medicine in many countries. The growth, medicinal components and nutrient contents of the plant are closely associated with endophytes, especially endophytic fung... Purslane, a common weed, has been used as food or folk medicine in many countries. The growth, medicinal components and nutrient contents of the plant are closely associated with endophytes, especially endophytic fungi. In this study, the endophytic fungi associated with purslane were isolated, and the effects of the isolates on the host were investigated to lay a foundation for further research and development of purslane resources. The results showed that a total of eight endophytic fungi were isolated from purslane (collected from Hohhot, Inner Mongolia, China), and they belonged to the genera Penicillium (isolates K, N, P, M and I), Chaetomium (isolate J), Fusarium (isolate H) and Petriella (isolate O). Moreover, the growth of purslane was significantly influenced by its endophytic fungi. Isolate M can significantly decrease the germination rate, while J can significantly increase the germination rate of purslane. In addition, H, J and M can significantly increase the bud length of purslane, and the fermentation broth of P has a negative influence on the bud length of purslane. M and I can significantly increase the height, fresh weight and chlorophyll content of purslane due, in part, to the lower pH of the fermentation broth of I and M. 展开更多
关键词 ENDOPHYTIC Fungi Purslane PORTULACA OLERACEA L. GROWTH Promotion GERMINATION
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Effects of temperature and light on seed germination of ephemeral plants in the Gurbantunggut Desert, China: implications for vegetation restoration 预览
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作者 CHEN Yanfeng CAO Qiumei +2 位作者 LI Dexin LIU Huiliang ZHANG Daoyuan 《干旱区科学:英文版》 SCIE CSCD 2019年第6期916-927,共12页
Seed germination is a key transitional stage in plant life cycle and is strongly regulated by temperature and light.Therefore, research on the effects of temperature and light on seed germination is extremely meaningf... Seed germination is a key transitional stage in plant life cycle and is strongly regulated by temperature and light.Therefore, research on the effects of temperature and light on seed germination is extremely meaningful for vegetation restoration, especially in desert ecosystems.Seeds of 28 ephemeral plants collected from the Gurbantunggut Desert of China were incubated at different temperatures(5℃/1℃, 15℃/5℃, 20℃/5℃, 25℃/10℃ and 30℃/15℃) in 12-h light/12-h darkness or continuous darkness regimes, and the responses of seed germination to temperature and light and the germination speed were studied in 2016.Results showed that seed germination percentage of the 28 ephemeral plants significantly differed to temperature and light.We classified the studied plants as the following groups based on their responses to temperature: 1 low temperature responsed plants, 12 moderate temperature responsed plants, 7 high temperature responsed plants, 4 non-responsed plants and 5 plants of no germination.It should be noted that Corispermum lehmannianum Bunge is sensitive to both moderate and high temperatures.There were 4 groups of plant in response to light, i.e., 7 light responsed plants, 10 dark responsed plants, 6 light non-responsed plants and 5 plants of no germination.Based on seed germination speed of the 28 ephemeral plants, we divided them into 4 patterns of germination, i.e., very rapid, moderately rapid, moderate and slow.Combining variations of temperature, precipitation and sand dune types in the study area, we suggested that very rapid and moderately rapid germinated plants could be used to moving sand dunes in early spring during vegetation restoration, moderate germinated plants could be used to semi-fixed sand dunes in late autumn, and slow germinated plants could be used to sand plain in summer.Thus, seedling establishment and vegetation restoration would be improved by considering seed germination characteristics of these ephemeral plants in the Gurbantunggut Desert, China. 展开更多
关键词 DORMANCY sand dune seed germination percentage seed germination pattern sowing time
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鸡血藤种子催芽试验研究 预览
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作者 林春兰 严坤麟 +3 位作者 罗万业 温秀凤 谢金兰 范剑明 《林业科技情报》 2019年第2期1-2,7共3页
比较不同成熟度与不同处理方式对鸡血藤种子发芽率的影响。结果表明:成熟果实的种子发芽率为71%,未成熟果实的种子发芽率为32.3%;用温水浸泡处理种子发芽率为73.3%,用直接湿沙贮藏处理种子发芽率为71.0%。因此鸡血藤应采摘成熟果实的种... 比较不同成熟度与不同处理方式对鸡血藤种子发芽率的影响。结果表明:成熟果实的种子发芽率为71%,未成熟果实的种子发芽率为32.3%;用温水浸泡处理种子发芽率为73.3%,用直接湿沙贮藏处理种子发芽率为71.0%。因此鸡血藤应采摘成熟果实的种子,催芽方式为40℃温水浸泡处理后,捞出置于温暖处催芽,或直接湿沙贮藏催芽均可。 展开更多
关键词 鸡血藤 催芽 贮藏 发芽率
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Vulnerability of Sunflower Germination and Metal Translocation under Heavy Metals Contamination 预览
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作者 Rumana Sadiq Nazimah Maqbool +3 位作者 Bader-Un-Nisa &ensp Kauser Parveen Mumtaz Hussain 《美国植物学期刊(英文)》 2019年第5期738-751,共14页
The germination and metal translocation ability of two sunflower seedlings were compared to identify the cultivar differences towards metal contamination at juvenile stage. The heavy metal treatments include: 0, 50, 1... The germination and metal translocation ability of two sunflower seedlings were compared to identify the cultivar differences towards metal contamination at juvenile stage. The heavy metal treatments include: 0, 50, 100, 150 and 200 mM Ni, Cd and Pb applied in sand filled pots to Hysun-33 and FH-533 sunflower. The highest germination percentage (79%) and vigor index were recorded for Hysun-33 with no heavy metal treatment. Pb and Cd treatments reduced the growth attributes of 20 days old seedlings of both the cultivars. The Ni translocation effectively enhanced the shoot and root biomass of Hysun-33. The high concentration of 150 and 200 mM Cd and Pb drastically reduced Mn and K contents, vigor, length and biomass of two sunflower cultivars. Among three of the heavy metals, Cd was found more toxic than Pb and Ni. Roots of 20 days old seedlings of Hysun-33 were able to hold more Cd metal and stop its translocation to epigenous parts. Although 150 and 200 mM Ni effects the germination and vigor of sunflower cultivars more than 50 and 100 mM Ni, it is found less toxic in comparison to Cd and Pb. The Cd accumulation in roots suggests that it is physiologically most active sink for Cd metal while epigenous parts of sunflower cultivars are sink for Pb and Ni metal as shoot of sunflower cultivars accumulates high contents of Pb and Ni. 展开更多
关键词 TRANSLOCATION GERMINATION Heavy Metals CONTAMINATION SUNFLOWER
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萌发条件对绿豆芽中γ-氨基丁酸含量的影响研究 预览
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作者 石磊 刘超 +1 位作者 周柏玲 孟婷婷 《粮食与油脂》 北大核心 2019年第3期50-53,共4页
以中绿2号为试验材料,采用析因试验设计,确定绿豆芽最佳的萌芽条件。结果表明:当浸种温度为40℃、浸种时间为24h,萌发时间为96h和萌发温度为15℃时的条件下,绿豆芽中GABA含量最高,测得的GABA含量为0.408mg/mL;考虑到生产应用,选用萌发... 以中绿2号为试验材料,采用析因试验设计,确定绿豆芽最佳的萌芽条件。结果表明:当浸种温度为40℃、浸种时间为24h,萌发时间为96h和萌发温度为15℃时的条件下,绿豆芽中GABA含量最高,测得的GABA含量为0.408mg/mL;考虑到生产应用,选用萌发温度为20℃,浸种温度为20℃,浸种时间为24h的萌发条件。在此条件下,谷氨酸和谷氨酸钠都可促进绿豆芽中GABA的转化生成,谷氨酸的促进作用高于谷氨酸钠。当谷氨酸的浓度为7.5‰时,绿豆芽中GABA含量最高,为0.467mg/mL。 展开更多
关键词 绿豆 萌发 Γ-氨基丁酸 萌芽条件 GABA
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Impact of Drought Stress during Germination on Antioxidant Capacities and Antioxidant Enzymes Activities of Madura Local Maize (<i>Zea mays</i>) Seeds 预览
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作者 Agnes Rezkyta Herwang Dani Tri Agus Siswoyo 《农业科学(英文)》 2019年第11期1506-1516,共11页
The effect of various polyethylene glycol (PEG) concentrations to induced drought stress on the antioxidant capacities and antioxidant enzyme activities was investigated on Madura local maize during germination. Seed ... The effect of various polyethylene glycol (PEG) concentrations to induced drought stress on the antioxidant capacities and antioxidant enzyme activities was investigated on Madura local maize during germination. Seed samples were treated under 5%, 10%, and 15% of PEG for 6 days. The changes in the antioxidant capacities such as 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and hydroxyl radical scavenging;antioxidant enzyme activities including catalase (CAT) and ascorbate peroxidase (APX) and gene expression were observed during seeds germination. The result showed the antioxidants capacities and enzyme activities exhibited a significantly higher level in drought-treated. The most effective level of drought stress to elevate the capabilities and enzyme activity of antioxidant as well as it gene expression was observed at 15% PEG, whereas ABTS scavenging activity was increased 20% over the control, hydroxyl scavenging activity up to 14%, CAT and APX activity increased 4 - 5 times over the control. Along with the presence of antioxidant mechanisms, including the capacities and activities of different types of ABTS+, hydroxyl, CAT, and APX might play important roles during the germination phase and be able to manage reactive oxygen species to the normal level under stress condition. 展开更多
关键词 Drought ANTIOXIDANT GERMINATION MAIZE Polyethylene-Glycol
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