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31.
云南及周边地区野菜和野果资源   总被引:2,自引:0,他引:2  
本文是根据“云南及周边地区生物资源调查”项目的系统调查结果汇总的。云南及周边地区野菜和野果资源,指的是该地区栽培蔬菜、果树及其野生近缘植物之外的可食的野菜和野果。云南及周边地区是多个少数民族聚居区,各少数民族都有采食野菜和野果的习俗,并且在长期采食野菜和野果中,积累了丰富的食用方法。本文介绍云南及周边地区的野菜和野果,旨在为深入研究和开发利用这些资源,并为国家制定野生植物保护有关政策提供基础数据和信息。  相似文献   
32.
研究得知湘南地区引进沾化冬枣、梨枣和骏枣的枣头一次枝(下简称枣头)伸长生长节律与本地品种鸡蛋枣相似,幼树期枣头有两次明显的伸长生长过程,其间出现生长暂缓期。从枣头年生长量看,三个引进品种均比本地品种鸡蛋枣要小,但秋季生长量比重均比鸡蛋枣还要大。三个引进品种果实均较鸡蛋枣大,果实生长规律均与鸡蛋枣相似。但各个品种果实生育期均长于鸡蛋枣。冬枣果实生育期最长为100天~110天,梨枣与骏枣果实生育较短,梨枣70天~75天,骏枣约85天,而鸡蛋枣只有65天~70天。  相似文献   
33.
【目的】探讨绿盲蝽Apolygus lucorum(Meyer-Dür)为害对枣树叶片光合作用的影响及其机制。【方法】以一年生冬枣Zizyphus jujuba cv.Dongzao和酸枣Ziziphus jujuba var.spinosa树叶片为试材,测定了绿盲蝽为害1,3,5和7 d时枣树叶片光合速率、气体交换、叶绿素荧光参数和叶绿素含量的变化。【结果】绿盲蝽为害3,5和7 d时冬枣叶片的净光合速率(net photosynthesis rate,Pn)较对照分别降低了55.83%,55.42%和59.61%;而酸枣叶片净光合速率仅在5和7 d时较对照分别降低了26.66%和27.34%。冬枣叶片的气孔导度被绿盲蝽为害3,5和7 d时较对照明显降低。冬枣叶片光合速率的下降与气孔导度(stomatal conductance,Gs)和总叶绿素含量的下降呈显著正相关,而酸枣叶片光合速率的下降仅与叶绿素含量显著正相关。绿盲蝽为害后冬枣和酸枣叶片的快速荧光诱导曲线受到显著影响。冬枣叶片的最大光化学效率(maximum photochemical efficiency,Fv/Fm)在绿盲蝽为害不同时间时相对于对照明显降低,而酸枣叶片没有受到明显的影响。绿盲蝽为害不同时间对冬枣和酸枣叶片的光系统Ⅱ放氧复合体(oxygen-evolving complex,OEC)以及光反应活性中心均造成了伤害,但酸枣受到的伤害程度明显低于冬枣。绿盲蝽为害5和7 d后冬枣叶片的光系统Ⅱ的电子传递活性降低,而酸枣叶片光系统Ⅱ的电子传递活性没有受到显著影响。绿盲蝽为害导致冬枣和酸枣叶片的电子传递的量子产额较对照明显降低,酸枣叶片中的降低幅度低于冬枣。【结论】绿盲蝽为害造成枣树叶片净光合速率明显降低,不同品种存在明显差异,冬枣叶片Pn降低程度明显高于酸枣。绿盲蝽为害后枣树叶片净光合速率的下降与叶绿素含量降低呈显著正相关。绿盲蝽为害影响了枣树叶片PSⅡ的结构和功能,导致供体侧的OEC受到伤害,光合作用PSⅡ反应中心失活,PSⅡ反应中心关闭程度增加,电子传递活性受到了抑制,其中酸枣叶片PSⅡ受到的影响明显低于冬枣叶片。  相似文献   
34.
Virus particles of approximately 740–760 nm in length and 13 nm in diameter were observed from a diseased Nicotiana tabacum (tobacco) plant in Sichuan Province, China. The complete genomic sequence of the virus isolate XC1 was determined to contain 9659 nucleotides without 3′ terminal poly(A) tail. XC1 has a genome typical of members of the genus Potyvirus, encoding a large polyprotein of 3075 amino acids. Putative proteolytic cleavage sites and a number of well characterized functional motifs were identified by sequence comparisons with those of known potyviruses. Sequence comparison revealed that XC1 shared the highest level of nucleotide sequence identity (76.5%) with Wild tomato mosaic virus (WTMV). Phylogenetic analysis showed that XC1 was closely related to the WTMV Guangdong isolate with an identity of 94.3% between CP gene sequence of the two viruses. We thus named XC1 WTMV‐XC‐1 as a novel isolate of WTMV. The full sequence of WTMV‐XC‐1 may serve as a basis for future investigations on the gene diversity of WTMV.  相似文献   
35.
A worldwide survey of babirusa skulls curated in museum and private collections located 431 that were from adult males and had retained at least one maxillary canine tooth. Eighty-three of these skulls were identified as exhibiting aberrant maxillary canine tooth growth. Twenty-four of the skulls represented babirusa from Buru and the Sula Islands, and forty-five skulls represented babirusa from Sulawesi and the Togian Islands. The remaining series of fourteen babirusa skulls originally came from zoo animals. Fifteen skulls showed anomalous alveolar and tooth rotation in a median plane. Twenty-nine skulls had maxillary canine teeth that did not grow symmetrically towards the median plane of the cranium. Fourteen skulls showed evidence that the tips of one or both maxillary canine teeth had eroded the nasal bones. Twenty-one skulls had maxillary canine teeth that had eroded the frontal bones. The teeth of two skulls had eroded a parietal bone. One skull had two maxillary canines arising from an adjacent pair of alveoli on the left side of the cranium. Three skulls exhibited alveoli with no formed maxillary canine teeth in them. Analysis suggested that approximately 12% of the adult male babirusa in the wild experience erosion of the cranial bony tissues as a result of maxillary canine tooth growth. There was no skeletal evidence that maxillary canine teeth penetrate the eye.  相似文献   
36.
A scabies outbreak, with unusually high mortality and morbidity, occurred in a poorly managed goat flock in north-eastern Italy. The source of infection was traced back to contact with scabietic chamois (Rupicapra rupicapra) within a recognised sylvatic focus of the disease. Spill-over of scabies from chamois to goats is a matter of great concern to resource managers. Currently scabies-free populations of wild Caprinae in the central and western Alps may eventually be exposed to infected goats transported over long distances. Sanitation of the studied flock was obtained following three applications of pour-on moxidectin at an approximate dose of 500 mcg/kg. Follow-up included titration of circulating anti-Sarcoptes antibodies in a labelled avidin–biotin ELISA test. Two operators developed pseudoscabies after handling the infested flock.  相似文献   
37.
采用氢化物-原子荧光法,对种植于黔中的来自以色列15个野生二粒小麦群体110个基因型籽粒含硒量进行检测分析.结果表明,15个群体含硒量差异极显著(P≤0.001);110个基因型籽粒硒含量和单粒硒含量分别为0.043~0.409 mg kg-1和0.008~0.125 mg seed-1,平均值分别为0.180 mg kg-1和0.046 mg seed-1.籽粒硒含量和单粒硒含量最低的基因型分别是Gamla群体的TZ120和Mt.Hermon群体的TZ8,最高的基因型分别为Bat-Shelomo群体的TZ36和TZ34.在群体水平上硒浓度差异明显,变异系数CV为9%~74%;斯皮尔曼秩相关分析表明,籽粒硒含量分别与该群体起源地海拔、年平均降雨量、平均干旱天数呈显著负相关,与年均温、8月均温、1月均温呈显著正相关.单粒硒含量的相关分析与籽粒硒含量的相似.野生二粒小麦籽粒含硒量的差异是长期适应环境的结果,其遗传多样性将为小麦硒营养机理研究和育种利用提供材料.  相似文献   
38.
The salt-tolerant green alga Dunaliella has remarkable capability to survive in some extreme environments such as nitrogen starvation, which makes Dunaliella be a proper model for mining novel genes on nitrogen uptake or assimilation. In this study, a glutamine synthetase (GS) gene DvGS2 with amino acid identity of 72% to other homologous GS proteins, was isolated and characterized from Dunaliella viridis. Phylogenetic comparison with other GSs revealed that DvGS2 occupied an independent phylogenetic position. Expressional analysis in D. viridis cells under nitrogen starvation confirmed that DvGS2 increased its mRNA level in 12 h. Subcellular localization study and functional analysis in a GS-deficient Escherichia coli mutant proved that DvGS2 was a chloroplastic and functional GS enzyme. In order to investigate the potential application of DvGS2 in higher plants, the transgenic studies of DvGS2 in Arabidopsis thaliana were carried out. Results showed that the transgenic lines expressed the DvGS2 gene and demonstrated obviously enhanced root length (29%), fresh weight (40%–48% at two concentrations of nitrate supplies), stem length (21%), leaf size (39%) and silique number (44%) in contrast with the wild-type Arabidopsis. Furthermore, the transgenic lines had higher total nitrogen content (35%–43%), total GS activity (39%–45%) and soluble protein concentration (23%–24%) than the wild type. These results indicated that the overexpression of DvGS2 in A. thaliana resulted in higher biomass and the improvement of the host's nitrogen use efficiency.  相似文献   
39.
完达山东部林区野猪种群数量和栖息地特征的初步分析   总被引:3,自引:0,他引:3  
2008 年11 月18 日至2009 年3 月20 日,为了调查黑龙江省完达山东部林区野猪种群数量和栖息地特征,我们采用随机布设样线的方法在东方红林业局境内13 个林场共布设大样方40 个,样线200 条。调查结果表明,东方红林业局境内野猪分布平均密度为0.175 头/ km2 , 种群数量为546 ~ 680 头;野猪主要分布在河口、奇源、青山、五林洞、独木河、海音山和东林7 个林场,位于海拔300 ~ 800 m 的范围内。1989 年调查的野猪平均密度为0.372 头/ km2 ,种群数量为1302 ; 2002 年调查的野猪平均密度为0. 342 头/ km2 , 种群数量为1 198 头。近年来野猪种群密度降低,种群数量呈加速下降趋势。对野猪栖息地特征分析表明,野猪喜欢选择中坡位、阳坡、坡度小于5°、地表植被盖度大于30% 、隐蔽度和郁闭度在25% ~ 50% 之间的生境。阔叶林、灌丛是野猪的主要栖息地。非法捕猎、森林采伐、坚果采摘和东北虎的捕食是造成野猪种群数量减少、栖息地质量下降的主要因素。  相似文献   
40.
浙江中部地区野榧的调查   总被引:1,自引:0,他引:1  
简述了浙江中部地区被称为"野榧"的植物,并非指一种植物,而是三尖杉、南方红豆杉、粗榧和野生榧树等几种植物.同时介绍了它们的叶与果实的主要区别;指出这些重要野生植物资源应加以保护.  相似文献   
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