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51.
云南野生稻生态类型丰富,且具有抗白叶枯病、抗稻瘟病、耐旱、耐寒等栽培稻不具有或已经消失的遗传基因,是水稻品种改良的优良基因库。然而,随着人类社会经济活动对生态环境影响的加剧,这一宝贵的战略性生物资源正面临着快速消失的危险。为了加强云南野生稻资源的保护,近年来,我们对云南野生稻资源开展了原生境保护(物理隔离方式和主流化方式)及非原生境保护(种质库、种质圃、细胞库和DNA库)等保护技术研究,明确了各种保护方法的优缺点和适用性,保护了云南野生稻的多样性和丰富度,为改良栽培稻储备了丰富的基因源。  相似文献   
52.
动物肠道菌群与宿主在营养代谢、免疫、疾病等方面有密切的关系。鉴于肠道菌群的这种重要性,野生动物肠道菌群宏基因组学日益成为保护生物学的研究热点。本文主要综述了近年来野生哺乳动物肠道微生物组的若干最新研究进展,着眼于宿主食性适应、健康、宿主与微生物组的协同进化等若干重要问题,对食肉类、灵长类、有蹄类、有袋类、鲸类、啮齿类等几大比较受关注的动物类群分别进行了总结,以期为今后我国哺乳动物肠道微生物组的研究提供一些视角和方向,并为野生动物的保护提供新的理论基础及研究手段。  相似文献   
53.
Our purpose was to evaluate the usefulness of the germination vs. the X-ray test in determining the initial viability of seeds of eight wild species (Salvia spinosa, Salvia aegyptiaca, Ochradenus baccatus, Ochradenus arabicus, Suaeda aegyptiaca, Suaeda vermiculata, Prosopisfarcta and Panicumturgidum) from Saudi Arabia. Several days were required to determine viability of all eight species via germination tests, while immediate results on filled/viable seeds were obtained with the X-ray test. Seeds of all the species, except Sa.aegyptiaca, showed high viability in both the germination (98–70% at 25/15 °C, 93–66% at 35/25 °C) and X-ray (100–75%) test. Furthermore, there was general agreement between the germination (10% at 25/15 °C and 8% at 35/25 °C) and X-ray (5%) tests that seed viability of Sa.aegyptiaca was very low, and X-ray analysis revealed that this was due to poor embryo development. Seeds of P.farcta have physical dormancy, which was broken by scarification in concentrated sulfuric acid (10 min), and they exhibited high viability in both the germination (98% at 25/15 °C and 93% at 35/25 °C) and X-ray (98%) test. Most of the nongerminated seeds of the eight species except those of Sa.aegyptiaca were alive as judged by the tetrazolium test (TZ). Thus, for the eight species examined, the X-ray test was a good and rapid predictor of seed viability.  相似文献   
54.
Our objective was to evaluate the usefulness of the germination vs. the X-ray test in determining the initial viability of seeds of five wild species (Moringa peregrina, Abrus precatorius, Arthrocnemum macrostachyum, Acacia ehrenbergiana and Acacia tortilis) from Saudi Arabia. Usually several days were required to determine the viability of all five species via germination tests. However, X-ray test will give immediate results on filled/viable seeds. Seeds of all species, except Acacia ehrenbergiana and Acacia tortilis showed high viability in both germination (96–72% at 25/15 °C, 94–70% at 35/25 °C) and X-ray (100–80%) test. Furthermore, there was a general agreement between the germination (19%, 14% at 25/15 °C and 17% and 12% at 35/25 °C) and X-ray (8%, 4%) tests in which seed viability of Acacia ehrenbergiana and Acacia tortilis was very low due to insect damaged embryo as shown in X-ray analysis. Seeds of Abruspreca torius have physical dormancy, which was broken by scarification in concentrated sulfuric acid (10 min), and they exhibited high viability in both the germination (83% at 25/15 °C and 81% at 35/25 °C) and X-ray (96%) tests. Most of the nongerminated seeds of the five species except those of Acacia ehrenbergiana and Acacia tortilis, were alive as judged by the tetrazolium test (TZ). Thus, for the five species examined, the X-ray test was proved to be a good and rapid predictor of seed viability.  相似文献   
55.
Edible mushrooms are well known for their value of nutrition. We analysed the contents of 17 amino acids in 41 species of common wild edible mushrooms in Yunnan Province. The results indicate that the types of amino acids are rich and the contents of amino acids are high. The total amino acids contents of Lyophyllum shimeji, Boletus griseus, Termitomyces bulborhizeus, and T.striatus are rather higher than others.  相似文献   
56.
明亮熊蜂和意大利蜜蜂为温室草莓的授粉行为比较观察   总被引:21,自引:0,他引:21  
蜜蜂和熊蜂都是理想的授粉昆虫,但熊蜂比蜜蜂更适合为温室果菜授粉,主要由于熊蜂和蜜蜂授粉时的活动方式不同。作者对明亮熊蜂和意大利蜜蜂为日光温室草莓授粉时的行为和活动方式进行了比较研究。结果表明,明亮熊蜂和意大利蜜蜂的授粉行为相似,但活动方式不同。明亮熊蜂开始访花的时间(8:00~8:05)比意大利蜜蜂(9:25~9:40)早,停止访花的时间(15:55~16:05)却比意大利蜜蜂(15:20~15:30)晚;开始访花的温度(12~13℃)也比意大利蜜蜂(>15℃)低,意大利蜜蜂在早晨和阴天不访花。明亮熊蜂个体的日活动时间271.43±4.48 s,明显比意大利蜜蜂个体的日活动时间180.00±2.64 s长,差异显著;而采集时间为105.71±1.16 s,显著长于意大利蜜蜂的76.43±3.83 s。明亮熊蜂每分钟平均访花数为8.44±0.44,极显著高于意大利蜜蜂每分钟的平均访花数2.38±0.15;明亮熊蜂访花间隔为3.81±0.42 s,极显著短于意大利蜜蜂的6.0±0.48 s。明亮熊蜂访花具有选择性,每天访早期花平均为55%,意大利蜜蜂则无选择性,每天访早期花平均为34%,二者差异显著;在9:00~12:00明亮熊蜂访早期花平均为75%,意大利蜜蜂访早期花则仅为31%。熊蜂在花间和花簇间活动频繁,平均移动距离为5.2 m;而意大利蜜蜂很少在花簇间移动,平均移动距离只有1.1 m。据此得出明亮熊蜂为日光温室草莓授粉的活动特性优越于意大利蜜蜂,从而产生更高的授粉效益。  相似文献   
57.
苏北滨海湿地麋鹿恢复种群的研究   总被引:1,自引:0,他引:1  
1986年至2004年,在苏北滨海湿地开展恢复麋鹿野生种群的研究。从每年的2月份开始,在麋鹿的产仔期按照每旬记录产仔数,直至产仔结束。逐年统计半散养和野生麋鹿种群结构。选择不同年龄阶段和不同性别的麋鹿进行称重,分析个体的身体发育程度。半散养麋鹿种群由1986年引进的39 头,发展到2004年的706 头,年均出生率21.7%,鹿群年均增长率为17.5%,现已繁殖了子四代;野生放养麋鹿由31 头增加到2004年的41头,年均出生率16.3%,年均增长率为9.0% ,且于2003年、2004年各产1 头完全属野生的子二代。产仔季节相由引进时的紊乱已调整至目前的规律性产仔。研究表明大丰麋鹿种群繁殖很成功,其寿命、行为、生理发育、繁殖周期等都较引进时发生了显著的变化,已完全适应了黄海湿地生态环境。人类活动干扰仍是影响麋鹿种群恢复的一个重要因素。  相似文献   
58.
Because there is some evidence that June Yellows (JY) of strawberry may be caused by a pathogenic agent, combinations of heat treatment and meristem-tip culture that are known to eliminate some viruses from tissues were used in attempts to cure affected Cambridge Favourite strawberry plants from JY. None of 397 propagants derived from JY-affected plants subjected to various combinations of these treatments were freed from JY. Indeed, all propagants showed more obvious JY symptoms than the parent plants from which they were derived, suggesting that such treatments may be useful for detecting incipient JY in symptomless strawberry stocks.  相似文献   
59.
Serum samples from 210 wild ruminants collected between 2006 and 2007 in southern Spain were tested for antibodies against bluetongue virus (BTV) by means of a competitive ELISA assay. Eighty-seven of the 210 wild ruminants analysed (41%) showed antibodies against BTV. Statistically significant differences were found in the seroprevalence among species: 66% (65 of 98) for red deer (Cervus elaphus), 50% (ten of 20) for fallow deer (Dama dama), 33% (three of nine) for mouflon (Ovis aries musimon) and 11% (nine of 83) for Spanish ibex (Capra pyrenaica). Overall, the sites where seropositive wild ruminants were found coincide with the areas where BTV had been detected in livestock, but in eastern Sierra Morena, the virus circulated in wild ruminants, although it had not been detected in domestic ruminants in the same areas. Wild ruminants over 1-year of age (sub-adults and adults) had significantly higher seroprevalences than juvenile animals. Statistically significant differences were also observed between BTV seroprevalence and management (free-ranging vs. captivity) with higher prevalence in free-ranging animals. The high seroprevalences obtained suggest that BTV is widespread in wild ruminants in southern Spain. This factor could have an important influence on the evolution of the infection in domestic livestock and indicates the need to include wild ruminant species in BTV surveillance or control programs. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
60.
Oryza grandiglumis Chitinase IVa (OgChitIVa) cDNA encoding a class IV chitinase was cloned from wild rice (Oryza grandiglumis). OgChitIVa cDNA contains an open reading frame of 867 nucleotides encoding 288 amino acid residues with a predicted molecular weight of 30.4 kDa and isoelectric point of 8.48. Deduced amino acid sequences of OgChitIVa include the signal peptide and chitin-binding domain in the N-terminal domain and conserved catalytic domain. OgChitIVa showed significant similarity at the amino acid level with related monocotyledonous rice and maize chitinase, but low similarity with dicotyledoneous chitinase. Southern blot analysis showed that OgChitIVa genes are present as two copies in the wild rice genome. It was shown that RNA expression of OgChitIVa was induced by defense/stress signaling chemicals, such as jasmonic acid, salicylic acid, and ethephon or cantharidin and endothall or wounding, and yeast extract. It was demonstrated that overexpression of OgChitIVa in Arabidopsis resulted in mild resistance against the fungal pathogen, Botrytis cinerea, by lowering disease rate and necrosis size. RT-PCR analysis showed that PR-1 and PR-2 RNA expression was induced in the transgenic lines. Here, we suggest that a novel OgChitIVa gene may play a role in signal transduction process in defense response against B. cinerea in plants. J.-H. Pak and E.-S. Chung contributed equally to this work.  相似文献   
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