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1.
耐盐碱促生菌的筛选及性能   总被引:1,自引:0,他引:1  
盐分是影响作物生长最重要的因素,使用能促进植物生长的耐盐碱促生菌减轻盐胁迫引起的损害是一种农业上的有效方法。文中从盐碱地筛选得到7株耐盐细菌,并考察筛选菌株的产胞外聚合物(EPS)能力、降碱能力和产吲哚-3-乙酸(IAA)能力。经综合评价选出1株优势菌株DB01,菌株DB01产EPS能力为0.21 g/g,降碱能力为8.7%,产IAA的能力为8.97 mg/L。菌株经16S rRNA鉴定为海水盐单胞菌Halomonas aquamarina,并且有抑制香蕉枯萎病、番茄早疫病、大豆疫霉病、小麦纹枯病病原菌的能力,同时能够在盐胁迫下促进小麦幼苗的发芽率和根长。海水盐单胞菌Halomonas aquamarina DB01可为土壤微生物资源开发利用和盐碱地改良提供理论依据。  相似文献   
2.
正动物园作为综合保护、科普宣传与公众教育的重要场所,在濒危物种的迁地保护工作中发挥着十分重要的作用(Kleiman et al.,2010)。然而,不同的濒危物种在生理学及生活史方面存在很大差异;加之部分物种的生物学信息匮乏,使得动物园的饲养繁育和疾病防控工作面临重大挑战。在常规体检及疾病诊断时,血液参数值有助于对动物机体的临床检查与诊断,解读动物的生理、营养和病理状态(胡翊群,2004;Etim et al.,2014),是及时发现动物  相似文献   
3.
Combinations of progesterone, lutenizing hormone releasing hormone analogue (LHRHa), human chorionic gonadotrophin (hCG), and the dopamine-2 (DA2) receptor antagonist 1-[1-[4,4-bis(4-Fluorophenyl)butyl]-4-piperidinyl]-1,3-dihydro-2H-benzimidazol-2-one (Pimozide; Orap) were tested for improvement of spawning rates, oocyte numbers, fertilization and neurulation rates of the Fowler toad (Bufo fowleri). Only treatments combined with progesterone produced large numbers of oocytes. The best treatment on oocyte numbers, neurulation rates, and the number of neurulas was with 5 mg progesterone, 20 mic.g LHRHa, and 0.25 mg Pimozide. Progesterone (5 mg) with 60 mic.g LHRHa gave high spawning rates, oocyte numbers, and fertilization rates but neurulation rates were low. Progesterone alone in high repeated doses did not result in ovulation. High doses of LHRHa (60 mic.g) with hCG, progesterone, and Pimozide gave the greatest number of toads spawning, however, they resulted in low oocyte numbers, fertilization and neurulation rates. A low dose of LHRHa (4 mic.g) with hCG, or hCG alone as a second administration, and progesterone with Pimozide produced few good quality oocytes. Toads were given normal ovulatory doses of hormones 24 or 48 hrs after their initial dose, but these resulted in low oocyte numbers followed by poor fertilization. Overall, these results suggest that progesterone with a dose between 20 mic.g and 60 mic.g of LHRHa may be optimal for the induction of ovulation in these toads. Moreover, Pimozide can supplement low doses of LHRHa but not replace it.  相似文献   
4.
珠颈斑鸠繁殖期占据领域鸣声特征及行为   总被引:10,自引:1,他引:9  
2003年4~6月,在四川省南充市通过野外观察、录音、室内计算机处理及声谱分析对珠颈斑鸠繁殖期占据领域鸣声特征及行为做了研究。结果表明:珠颈斑鸠有一般占据和召唤配偶共同占据两类鸣声,两类鸣声雌雄不同,但均由3音节组成;其鸣唱具有应答性,且每次在各栖位点的鸣唱顺序大致相同;日鸣唱频次变化大,具3个高峰期;繁殖各时期鸣唱频次变化亦大。  相似文献   
5.
圈养白头叶猴春季昼夜活动节律   总被引:1,自引:0,他引:1  
2008年3~5月,采用瞬时扫描法,对上海动物园5只白头叶猴的行为进行24h昼夜连续观察。结果表明:春季圈养白头叶猴一天的活动起于06∶00左右,结束于18∶00或18∶30。白天白头叶猴的主要行为为休息、取食和移动,平均频次依次是13.79次、4.75次和2.18次。夜间的主要行为为休息、移动和抓挠,平均频次依次是22.13次、0.43次和0.26次。不同个体昼夜活动节律差异很大。其中,移动、理毛、玩耍和其它行为的差异显著。夜间无理毛和玩耍行为,移动行为在夜间21∶00,00∶30,03∶00和04∶30出现高峰。在22∶30,01∶00,02∶00,03∶30,04∶30和05∶30则出现抓挠高峰。这预示白头叶猴夜间休息时处于一个"轻睡眠"状态。同时,雌雄白头叶猴昼夜移动行为差异显著。  相似文献   
6.
Twelve polymorphic microsatellite loci were isolated and characterized from a Chinese endemic species Polytremis nascens Leech. The isolated loci in 53 individuals from six regional populations in China had 3–12 alleles. Analyses revealed that 53 individuals had different multilocus genotypes, with the expected heterozygosity ranging from 0.61 to 0.90 and observed heterozygosity ranging from 0.33 to 0.71. Eleven loci showed no deviation from Hardy–Weinberg proportions, and eight were amplified successfully in at least one of the eight related species. The described isolated markers will facilitate the study of population genetic structure and gene flow in P. nascens as well as in congeneric and related species.  相似文献   
7.
Skippers of the tribe Baorini are evidently a monophyletic group in the subfamily Hesperiinae. In this study, a new Baorini member Tsukiyamaia albimacula gen. n. et sp. n. is described from north Myanmar, southwest China and north Vietnam. Despite its peculiar and striking wing-pattern, this new genus has some important characters of Baorini, such as a broad and bifid uncus and a well-developed gnathos. Based on an analysis of male genitalia and the molecular phylogenies inferred from both mitochondrial and nuclear genes (28 taxa, total aligned length: 2968 bp), it is proposed that the genus Tsukiyamaia is closely related to the genus Polytremis, which has high species diversity in China. This study not only describes a new skipper but also highlights that Tsukiyamaia is important in clarifying phylogenetic relationship of Polytremis and its allies.  相似文献   
8.
为了探究环境丰容和食物丰容对岩羊行为和活动节律的影响,于2017年3月—7月,以上海动物园的5只雌性岩羊(Pseudois nayaur)为研究对象,设计环境丰容和食物丰容试验,利用瞬时扫描法对岩羊进行行为学观察,分析岩羊丰容前后昼间行为的变化。结果表明:经过环境丰容,岩羊的运动行为和反刍行为显著增加,卧息行为和其他行为显著减少,取食行为无明显变化。在环境丰容基础上,开展食物丰容后,运动行为明显减少,取食行为明显增加。卧息行为有所减少、反刍行为和其他行为有所增加,但变化均不明显。丰容后岩羊的昼间活动节律也发生了变化。取食行为呈现2个高峰期(8:00—11:00和15:00—18:00),取食行为普遍提高;运动行为在13:30—17:30时段较丰容前提前一个小时左右发生;卧息行为有相似的波动规律,但丰容后其昼间发生频次在16:00之前均降低;反刍行为波动最大,呈现出明显的2个高峰期(6:00—9:00和10:00—15:00)。试验表明,在进行环境和食物丰容后,岩羊的活动增加,优化了时间分配,福利状况得到了有效改善。  相似文献   
9.
Botrytis cinerea is an economically important fungal pathogen with a host range of over 200 plant species. Unfortunately, gray mold disease caused by B. cinerea has not been effectively controlled because of its high risk for fungicide resistance development. As a part of our ongoing efforts to develop novel sulfonamides as agricultural fungicides against Botrytis cinerea, we introduced 2-aminoethanesulfonic acid (taurine) substructure, designed and synthesized a series of novel 2-substituted acylaminoethylsulfonamides. The newly synthesized sulfonamides were evaluated in vitro and in vivo for their fungicidal activity against Botrytis cinerea, of which the 2-ethoxyacetylamide derivative (V-A-12, EC50 = 0.66 mg·L−1) exhibited the highest potency in vitro and superior fungicidal activity compared with procymidone (EC50 = 1.06 mg·L−1). In vivo bioassay indicated that compound V-A-12 could be effective for the control of tomato gray mold. Moreover, the structure-activity relationship of these sulfonamides was analyzed by establishing a three-dimensional quantitative structure-activity relationship (3D-QSAR) model, which can provide guidance for the development of sulfonamides as fungicides. Finally, the effeicacy of sulfonamide derivatives was again verified in the activity evaluation against resistant Botrytis cinerea strains. These results further enhance the development value of 2-substituted acylaminoethylsulfonamides to control the tomato gray mold.  相似文献   
10.
2019年12月10日至2020年1月,在上海市浦东新区南汇东滩滴水湖水域持续观察和拍摄到一种鸭科鸟类。经查文献并与所观察记录到的鸟类进行形态特征比对,鉴定为丝绒海番鸭(Melanitta fusca),为中国鸟类分布新记录种。  相似文献   
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