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1.
为探明能源型植物柳枝稷(Panicum virgatum)新收获种子的萌发和出苗对环境条件的要求,研究了温度、光照和播种深度对柳枝稷种子萌发和出苗的影响。结果表明,柳枝稷种子萌发的适宜温度为30~35 ℃,此时发芽率、发芽势和发芽指数均明显高于其他温度处理;其发芽率不受光照影响,但光暗交替条件下的发芽速率、发芽势和发芽指数较黑暗条件下显著提高;其适宜的播种深度为2~16 mm,不覆土或播种过深均不利于出苗。  相似文献   

2.
湘杂芒2号种子发芽条件的研究   总被引:1,自引:0,他引:1  
以人工远缘杂交新品种湘杂芒2号(Miscanthus sinensis×lutarioriparia)为材料,研究了温度、发芽床、光照、贮藏条件、带颖壳与去颖壳等处理对芒属植物种子发芽的影响.结果表明,湘杂芒2号种子在15和45℃条件下不发芽,在变温条件下(20℃/30℃)发芽率最高,为96%;纸上发芽的平均发芽率最高,为94%;在光照和黑暗条件下发芽率和发芽指数差异均不显著;在4℃的冰箱冷冻和在室温下非密封保存1年后,平均发芽率超过85%,而在-20℃条件下保存1年后萌发率为0;种子去颖壳后发芽率由66%提高到86%.该结果能为芒属植物种苗繁殖体系的建立提供基础.  相似文献   

3.
超旱生小灌木红砂是干旱半干旱区优势乡土物种,但是种子依靠萌发繁殖活力较低,研究赤霉素与不同浓度盐交互作用对红砂种子萌发的影响,对于植被恢复和改善我国西部的生态环境具有重要作用。本试验采用培养皿纸上发芽法,对红砂种子进行不同赤霉素浓度(100、200、400、600 mg/L)、盐浓度(50、100、150、200、250、300mmol/L)以及赤霉素与盐交互作用3种处理,以蒸馏水处理为对照,研究赤霉素对盐胁迫后红砂种子萌发和幼苗生长情况的影响。结果表明:盐胁迫抑制种子的萌发,红砂种子的发芽率随盐浓度升高逐渐下降,发芽整齐度随浓度升高而逐渐增大,胚根长与盐浓度具有显著负相关关系(R~2=0.9452);使用较高浓度的赤霉素处理红砂种子,发芽率、发芽指数与发芽速度均随浓度增大而先减小后增大的趋势,阈值为200mg/L,不同浓度赤霉素处理后的红砂种子的胚根长及胚芽长之间无显著性差异;赤霉素对较高浓度(100mmol/L)盐胁迫后红砂种子的发芽率有显著的改善作用,可以提高种子的发芽速度、发芽指数。赤霉素能促进盐胁迫后红砂的种子萌发,促进胚的发育。  相似文献   

4.
温度、光照和发芽床对假俭草种子萌发的影响   总被引:3,自引:0,他引:3  
实验室内进行了假俭草种子净度检验样品最低限量和发芽检验方法的研究,探讨了光照(以黑暗为对照)、温度(分别包括20℃恒温,15/25℃、20/30℃、20/35℃和25/35℃变温)和发芽床(分设纸上TP和砂中S)等因素对种子发芽的影响。结果表明:假俭草种子净度检验样品最低限量是3g,送验样最低量以及计数其它植物种子检验样品最低量均为30g;最佳萌发条件为20/30℃或20/35℃变温(16小时低温,8小时高温),高温时段设光照,和纸上(TP)发芽;发芽的初次和未次计数时间分别以第10天和第21天为宜;种子的幼苗发育可划分为单子叶植物子叶留土类型。  相似文献   

5.
扁穗雀麦种子萌发吸水特性与萌发温度的研究   总被引:1,自引:0,他引:1  
对扁穗雀麦种子萌发吸水特性与不同温度处理下的萌发进行研究,结果表明:扁穗雀麦种子萌发吸水过程大致可分为三个阶段,吸水速度呈先快后慢的趋势,在2h时达最大值0.1363g/h,种子萌发最低吸水量为种子原重量的83.66%.在不同温度处理下,扁穗雀麦种子在25~30℃恒温条件下萌发相对较好,发芽率达97%,发芽指数较高.25℃萌发条件下活力指数最大,为679.41,其次为30℃.胚根的适宜生长温度为20~30℃,胚芽为25℃.综合发芽率、发芽指数和活力指数,最后确定扁穗雀麦的最适发芽温度为25~30℃.当温度降低到10℃或升高到40℃时,种子发芽受阻,发芽率均为0.  相似文献   

6.
塔落岩黄芪种子发芽标准的确定   总被引:12,自引:0,他引:12  
试验探讨了果壳、光、温度、发芽床对塔落岩黄芪种子萌发的影响。温度设处理20℃、25℃、30℃恒温及15 ̄25℃和20 ̄30℃变温;恒温下设黑暗与光照2个处理;发芽床设纸上、纸间、竖纸卷、沙上、沙中5个处理。试验选出了最适合于塔落岩黄芪种子萌发的最佳组合,并根据塔落岩黄芪种子萌发时的发育特征,确定了种苗鉴定标准和初次、末次计数时间。  相似文献   

7.
甘肃贝母种子吸水及发芽特性研究   总被引:3,自引:0,他引:3  
 对经后熟处理的甘肃贝母种子吸水规律进行测定,并设置不同温度(10,15,20,25,10/20℃变温)进行发芽试验,旨在为其人工驯化栽培提供依据。结果表明,甘肃贝母种子千粒重为0.72~0.82g。经20℃保湿储藏45d基本完成形态后熟,沙子与种子(4∶1)混合5~10℃层积150d基本完成生理后熟,种子吸水过程符合Logistic曲线,分急剧吸水期、稳定吸水期和饱和吸水期3个阶段。温度对经后熟处理的甘肃贝母种子发芽质量具有显著影响。黑暗下10~15℃内,随温度升高发芽质量显著改善,15℃ 发芽最佳,发芽率和发芽势分别达90.67% 和89.33%。当温度超过15℃,发芽质量又显著降低,高温还抑制芽的伸长。以上结果说明经后熟处理后,温度是决定甘肃贝母种子发芽质量的关键因素。建议生产中当土温达15℃是甘肃贝母种子最佳播期,育苗期应保湿遮阳。  相似文献   

8.
郁金香种子休眠特性及发芽条件的研究   总被引:1,自引:0,他引:1  
针对郁金香(Tulipa gesneriana)种子在常温条件下难以萌发,冷藏条件下萌发时间过长、萌发率过低、易发霉等问题,在现有研究基础上通过刺破种子、改善芽床等手段对发芽条件进行改进,探讨常温条件下种子的萌发情况。结果显示,野生郁金香种子存在深度休眠现象,低温、激素处理、刺破种子、改善芽床等方法有助于解除休眠;光照、室温储藏对解除郁金香的休眠意义不大。在萌发过程中,郁金香种子有一个较长时间的吸胀萌动期,且表现出明显的序次萌发现象。常温条件下,储藏6个月后的当年郁金香种子在4℃条件下冷藏15 d后,刺破种子,接种在质量浓度为0.5 mg/L的GA3培养基上持续光照,10 d后有种子萌发,30 d种子萌发率达25%,45 d时达50%,50 d后发芽率为95%,而同样条件下没刺破的种子发芽率极低。4℃、-10℃的冷藏温度处理的种子,发芽率之间无显著差异(P0.05)。郁金香胶质状的胚乳对胚有一定的束缚作用,刺破种子可显著提高种子的萌发率。芽床对种子的萌发具有重要的作用,培养基的使用,既保证了种子在萌发过程中的营养物质供应,又使种子受到培养基中GA3的持续作用,而纸床往往因为污染而使种子过早终止发芽。  相似文献   

9.
环境因子对苦豆子种子萌发和幼苗生长的影响   总被引:4,自引:2,他引:4  
王进  韩多红  陈叶  金自学 《草地学报》2007,15(3):259-262
研究光照、温度、水分和土壤盐分等因子对苦豆子(Sophora alopecuroides L.)种子萌发的影响.结果表明:在持续光照、持续黑暗和16 h光照/8 h黑暗下种子萌发最适宜的温度为25℃;在16~8 h光暗交替下,25℃/16℃昼夜变温发芽率最高;种子萌发对光照不敏感;种子萌发最适土壤含水量为8%~13%;种子发芽期对NaCl的耐受浓度为1.2%.  相似文献   

10.
不同温度对多年生禾草种子发芽的影响   总被引:15,自引:4,他引:11  
设置了6种恒温、5种变温,对22种多年生禾本科牧草种子进行发芽试验,根据各温度下的发芽率、发芽指数、最初萌发时间等指标,来探讨发芽的最适温度。结果表明,供试种子在变温下的发芽率普遍高于恒温下,20℃时种子在萌发的第9d按发芽指数统计有13种达最大值,所有品种的发芽指数对温度反应的排序为5<10<10~15<15<20℃,各牧草种子的发芽最初萌发时间随温度的升高而缩短,发芽的最适温度因种和品种而异,本试验的22种牧草发芽最适温度在15~25℃之间。  相似文献   

11.
本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。  相似文献   

12.
用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10~0.82μg/g。表明:蜂蜜应视为天然富硒营养品。  相似文献   

13.
乳酸杆菌益生作用机制的研究进展   总被引:2,自引:0,他引:2  
乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和 Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。  相似文献   

14.
以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。  相似文献   

15.
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。  相似文献   

16.
Reasons for performing study: Clinical experiences indicate that centesis of the lateral compartment of the femorotibial joint is often unsuccessful. Objective: To determine the accuracy of 2 published and 2 unpublished techniques of centesis of the lateral compartment of the femorotibial joint. Hypothesis: It was hypothesised that a drug can be administered into the lateral compartment of the femorotibial joint via a diverticulum of this joint that surrounds the medial aspect of the long digital extensor tendon and that this technique is more accurate than described techniques of centesis of this compartment. Methods: Twenty‐four stifles of 12 horses were divided equally into 4 groups and a radiocontrast medium injected into the lateral compartment of the femorotibial joint of each group using a hypodermic needle inserted: 1) caudal to the lateral patellar ligament and proximal to the tibial plateau, 2) caudal to the long digital extensor tendon and proximal to the tibial plateau, 3) between the long digital extensor tendon and bone of the extensor groove of the tibia or 4) directly through the long digital extensor tendon until it contacted bone. Twelve veterinary students who had no experience using any of these techniques performed the injections. Accuracy of each technique was determined by examining radiographs obtained after injecting the contrast medium. Results: The most successful technique for arthrocentesis was by inserting a needle through the long digital extensor tendon. This approach was successful in all attempted cases, whilst other techniques had lower rates of success. Conclusions: The lateral compartment of the femorotibial joint can be accessed accurately by inserting a needle through the long digital extensor tendon as it lies within the extensor groove. Other techniques may not be as accurate for clinicians inexperienced in arthrocentesis of the lateral compartment of the femorotibial joint.  相似文献   

17.
This experiment was aimed to study the nutritional content and value of the muscles of two mallards (White feather mallard and mallard),and provide basic data and theoretical basis for the development and utilization of mallard meat products.60 White feathered mallards and mallards (30 for each breed,half of male and female) were chosen,and the composition and content of pectoral muscle crude protein,crude fat,cholesterol,amino acids,fatty acids,trace elements and vitamins were determined according to national standards and the nutritional values of muscle were evaluated.The results showed that the content of crude protein in muscle of White feather mallard was significantly lower than that of mallard (P<0.05).17 kinds of amino acids with contents higher than 0.01% were detected in the muscles of the two kinds of mallards,among which the contents of threonine,histidine,serine and proline in the muscles of the White feather mallard were significantly higher than those of mallard (P<0.05).The contents of lysine,glutamate and arginine were significantly lower than those of mallard (P<0.05).13 kinds of fatty acids with contents higher than 0.01% were detected,and the contents of stearic acid and oleic acid were significantly lower than those of the mallard.9 mineral elements (sodium,magnesium,potassium,calcium,manganese,iron,copper,zinc and selenium) in two kinds of mallards were detected,and there was no significant difference between the two kinds of mallards (P>0.05).8 kinds of vitamins were detected,and the content of vitamin B1 in muscle of White feather mallard was significantly higher than that of mallard (P<0.05),but the contents of vitamin D and vitamin E were significantly lower than that of mallard (P<0.05).The ratio of amino acids in muscle of two kinds of mallards was close to the ideal model recommended by WHO,which was rich in mineral elements and vitamins for human body,and had a broad prospect of development and utilization.  相似文献   

18.
本试验旨在研究两种绿头鸭(白羽绿头鸭和绿头鸭)肌肉营养组成和价值,为绿头鸭肉产品的开发利用提供基础数据和理论依据。选择白羽绿头鸭和绿头鸭60只(每个品种各30只,公母各半),依照国家标准测定胸肌粗蛋白质、粗脂肪、胆固醇含量及氨基酸、脂肪酸、微量元素和维生素的组成和含量,并对胸肌进行氨基酸评价及脂肪酸营养价值评价。结果显示,白羽绿头鸭肌肉粗蛋白质含量显著低于绿头鸭(P<0.05);两种绿头鸭肌肉中均检测到17种含量大于0.01%的氨基酸,其中白羽绿头鸭肌肉苏氨酸、组氨酸、丝氨酸和脯氨酸含量显著高于绿头鸭(P<0.05),赖氨酸、谷氨酸和精氨酸含量显著低于绿头鸭(P<0.05);检测到13种含量均大于0.01%的脂肪酸,其中白羽绿头鸭硬脂酸和油酸含量显著低于绿头鸭(P<0.05);检测到9种矿物质元素(钠、镁、钾、钙、锰、铁、铜、锌和硒),两种绿头鸭差异不显著(P>0.05);检测到8种维生素,白羽绿头鸭肌肉维生素B1含量显著高于绿头鸭(P<0.05),维生素D和维生素E含量显著低于绿头鸭(P<0.05)。两种绿头鸭肌肉氨基酸比例接近世卫组织推荐的理想模式,富含人体所需的矿物质元素和维生素,具有广阔的开发利用前景。  相似文献   

19.
应用光镜和透射电镜技术,观察了3~6月龄比格犬甲状腺的显微和超微结构。结果表明,比格犬甲状腺实质由滤泡和滤泡旁细胞构成。滤泡呈圆形或椭圆形,直径20.22~220.00μm,平均90.80μm;由单层立方上皮细胞围成,细胞高度3.04~7.11μm,平均5.18μm,电镜下可见功能状态不同的两型滤泡上皮细胞;滤泡旁细胞很多,直径4.40~8.82μm,平均6.23μm,位于滤泡之间或镶嵌于滤泡上皮细胞之间,也可聚集在一起形成滤泡样结构,胞质内含有大量的分泌颗粒,电镜下也可见两种类型的滤泡旁细胞。  相似文献   

20.
A retrospective review of records of 205 cats with histologically confirmed disease of the spinal cord was performed to identify the prevalence of disease in this nonrandomly selected population of cats. Clinical records were reviewed, and age, duration of neurologic illness, and clinical and histopathologic findings in cats with spinal cord disease were abstracted. Disease processes were classified into 7 categories and 23 groups. The most common diseases affecting the spinal cord of cats were feline infectious peritonitis (FIP), lymphosarcoma (LSA), and neoplasia of the vertebral column secondarily affecting the spinal cord. Information on age, onset and duration of clinical signs, and lesion localization at the postmortem examination in cats belonging to the 7 categories of disease were analyzed to create a practical list of differential diagnoses. Cats were also subcategorized into 3 groups based on their age at death. FIP was the most common disease of cats younger than 2 years of age. LSA and vertebral column neoplasia were the most common diseases affecting cats between 2 and 8 years of age. Vertebral column neoplasia was the most common disease affecting cats older than 8 years of age. Results of this histopathologic study showed that FIP and LSA were the most common disease processes affecting the spinal cord of cats. However, at least 21 other groups of diseases and their relative prevalence were identified.  相似文献   

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