不同产地山芹萸种实性状变异分析

山茱萸〔Ｍａｃｒｏｃａｒｐｉｕｍｏｆｆｉｃｉｎａｌｉｓ (Ｓｉｅｂ .ｅｔＺｕｃｃ .)Ｎａｋａｉ〕为重要的木本药用植物 ,果皮名曰萸肉 ,枣皮 ,果肉中含有 16种氨基酸、2 3种微量元素以及丰富的维生素、有机酸、鞣质、多种甙、黄酮等 ,具有多种药用功效 ,是名贵的中药[1] 。同时 ,山茱萸又是一种非常好的观赏树种 ,具有较高的经济价值和良好的开发应用前景[2 ] 。山茱萸的栽培已有 10 0 0多年的历史 ,但对其研究主要集中在营养和药用成分分析、种子休眠以及栽培技术等[3～ 5] 。作者分析了不同产地、不同母树山茱萸种实性状的变异状况 ,…     

明亮熊蜂繁育室内印度谷斑螟的形态特征与生物学特性

明亮熊蜂Bombus lucorum L.是一种重要的温室果菜传粉昆虫,印度谷斑螟Plodia interpunctella(Hbner)是危害明亮熊蜂繁育的主要害虫之一。2年的研究结果表明,印度谷斑螟的形态特征与危害蜜蜂巢房的大蜡螟Gallerie mellonellaL.和小蜡螟Achroia grisella Fabricius明显不同。印度谷斑螟以饲喂熊蜂的花粉为载体传播进熊蜂繁育室,在熊蜂繁育室内可以连续繁殖,1年发生6～8代,且世代重叠。印度谷斑螟幼虫主要以蜂群内的剩花粉为食,当花粉不足时,就开始取食巢房和蜂蛹,对熊蜂的规模化繁育危害较大,每年的5～8月、11～2月为危害高峰期。印度谷斑螟的发育受环境和食物的影响很大,在温度为28℃、相对湿度为60%熊蜂繁育室内,印度谷斑螟的卵期为4d,幼虫期为19～23d,蛹期为11d,成虫期为4～20d。成虫羽化后3～4h即可进行交配,雌蛾交配后当天就开始产卵,产卵期4～10d不等,平均产卵量107.8粒。在熊蜂繁育室消毒期间,食物短缺,印度谷斑螟幼虫进入休眠状态,各龄幼虫均可发生休眠现象。印度谷斑螟不危害蜜蜂,在蜜蜂巢房中不能存活。     

Reconstructing asymmetrical reproductive character displacement in a periodical cicada contact zone

Selection against costly reproductive interactions can lead to reproductive character displacement (RCD). We use information from patterns of displacement and inferences about predisplacement character states to investigate causes of RCD in periodical cicadas. The 13-year periodical cicada Magicicada neotredecim exhibits RCD and strong reproductive isolation in sympatry with a closely related 13-year species, Magicicada tredecim. Displacement is asymmetrical, because no corresponding pattern of character displacement exists within M. tredecim. Results from playback and hybridization experiments strongly suggest that sexual interactions between members of these species were possible at initial contact. Given these patterns, we evaluate potential sources of selection for displacement. One possible source is 'acoustical interference', or mate-location inefficiencies caused by the presence of heterospecifics. Acoustical interference combined with the species-specificity of song pitch and preference appears to predict the observed asymmetrical pattern of RCD in Magicicada. However, acoustical interference does not appear to be a complete explanation for displacement in Magicicada, because our experiments suggest a significant potential for direct sexual interactions between these species before displacement. Another possible source of selection for displacement is hybrid failure. We evaluate the attractiveness of inferred hybrid mating signals, and we examine the viability of hybrid eggs. Neither of these shows strong evidence of hybrid inferiority. We conclude by presenting a model of hybrid failure related to life cycle differences in Magicicada.     

Character displacement and the evolution of mate choice: an artificial neural network approach

Interactions with heterospecifics can promote the evolution of divergent mating behaviours between populations that do and do not occur with heterospecifics. This process--reproductive character displacement--potentially results from selection to minimize the risk of mating with heterospecifics. We sought to determine whether heterospecific interactions lead to divergence of female preferences for aspects of conspecific male signals. We used artificial neural network models to simulate a mate recognition system in which females co-occur with different heterospecifics in different populations. Populations that evolved conspecific recognition in the presence of different heterospecifics varied in their preferences for aspects of conspecific male signals. When we tested networks for their preferences of conspecific versus heterospecific signals, however, we found that networks from allopatric populations were usually able to select against heterospecifics. We suggest that female preferences for aspects of conspecific male signals can result in a concomitant reduction in the likelihood that females will mate with heterospecifics. Consequently, even females in allopatry may discriminate against heterospecific mates depending on the nature of their preferences for conspecifics. Such a pattern could potentially explain cases where reproductive character displacement is expected, but not observed.     

扁藻多糖的性质及结构特征的研究

利用不同浓度范围的乙醇从培养至平衡期后的扁藻细胞内沉淀分离出不同组分的扁藻多糖级分,对其理化性质和结构特征进行了相应的测定和对比分析。结果表明,经过凝胶层析分离后,乙醇浓度在0%~50%范围时沉淀的扁藻多糖与乙醇浓度为50%~75%范围时沉淀的扁藻多糖相比,前者分子量大、糖含量高、其结合的蛋白质也多,但前者的溶解度和粘度小于后者。两个级分的扁藻多糖的官能团相似,均含有硫酸基和氨基,但其含量不同。所得结果为深入研究扁藻多糖的结构及其实际应用提供了实验依据。     

竹类植物的观赏特性及造景艺术手法

分析了竹类植物的观赏特性,讨论其在园林中的造景方式及与园林各要素间的造景艺术手法,并探讨竹类植物的造景原则。     

蜜蜂抗狄斯瓦螨机制的研究进展

狄斯瓦螨Varroa destructor已蔓延至世界各地,给养蜂生产带来巨大挑战,被认为是世界养蜂业的主要威胁。因此,抗螨机制的研究和抗螨蜂种的培育显得尤为重要,而掌握蜜蜂的抗螨机制则是成功培育抗螨蜂种的前提条件。本文从行为、生理及分子机制等多个不同角度对国内外蜜蜂抗狄斯瓦螨机制研究的最新进展进行了详细的阐述。尤其是从分子水平研究蜜蜂的抗螨机制对选育抗螨蜂种具有重要意义,将为利用分子遗传辅助标记筛选方法和先进的生物工程技术并结合传统的育种手段成功培育出具有抗螨性能的优良蜜蜂品系奠定基础。     

9个小麦品种(系)比较试验中的主要农艺性状

目的:通过对9个小麦品种(系)的比较试验中的主要农艺性状统计分析,筛选出比较适宜现阶段在贵阳地区乃至贵州省栽培的高产优质小麦品种(系)。方法:9个小麦品种(系)在试验地里随机区组排列,3次重复,记录小麦的全生育期,出苗数,田间生育期,株高,有效分蘖数,每株干重,穗长,穗粒重等,并在Excell上进行统计分析。结果:全生育期在200天左右,出苗数有3个超过100万/ha,最低只有44．8万/ha,株高在50 cm以上的有6个品种(系),3个在40 cm-50 cm之间,有效分蘖数400万/ha以上的有3个,最低的是199．1万/ha,每株干重最高是8．5 g,最低是5．7 g,穗长整齐度除98-22外都优于对照,经LSR法测验表明,贵农15,黔98353,黔麦15分别与夏繁29,98-28,贵单5号,黔98284-82,黔0110都达到差异显著水平,贵农15,黔98353,黔麦15分别与98-22达到差异极显著水平,其余的差异皆不明显。结论:可以初步得出贵农15,黔98353,黔麦15目前可以作为在贵阳地区推广种植的较优品种(系)。