Relationships between mass mortality of two oak species (Quercus mongolica Turcz. var.grosseserrata Rehd. et Wils. andQ. serrata Thunb.) and infestation by and reproduction ofPlatypus quercivorus (Murayama) (coleoptera: Platypodidae)

This study investigated the number of adults ofPlatypus quercivorus (Murayama) captured on host oak (Quercus spp.) trees, the attack density (the number of entry holes per 100 cm²), and the number of emerging adults to clarify the relationships between the beetle’s colonization on trees in oak stands and tree mortality. The initial attack ofP. quercivorus, which was the most intense attack, was observed on most living trees simultaneously. Although some attacked trees died within the year of the attack or in the next year, a high density of attack did not usually cause the death of host trees. Surviving trees suffered low levels of consecutive attack after the initial attack. BecauseP. quercivorus successfully produced broods only in the dead trees, the population of the insect seems to be maintained only in stands where oak mortality occurs. However, the adults that landed on most of the surviving trees appeared unable to reproduce probably due to degradation of host quality. Thus, oak mortality probably ceases within 3 or 4 years after the start of infestation in a stand, with subsequent reductions in population density of the borer.     

An extended random primer amplified region (ERPAR) marker linked to a dominant male sterility gene in cabbage (Brassica oleracea var. capitata)

Similar to SCAR, an extended random primer amplified region (ERPAR) marker is a PCR amplified genomic DNA fragment at a single genetically defined locus. However, ERPAR uses specific primer pairs derived from RAPD primers by adding bases sequentially to their 3′-ends. As an example, an ERPAR marker was derived from a RAPD marker (OT11₉₀₀) linked to a dominant male sterility gene in cabbage (Brassica oleracea var. capitata). After two cycles of base adding and primer pair screening, a primer pair (5′-TTCCCCGCGACT-3′and 5′-TTCCCCGCGAGA-3′) amplified a single intense band with the same size as OT11₉₀₀. The identity of the new marker and OT11₉₀₀ was verified by segregation analysis. The new marker amplified by this extended primer pair was named as EPT11₉₀₀. The development of ERPAR exploits the importance of 3′-end bases of primers in PCR ERPAR shares advantages of SCAR, but eliminates the need for cloning and sequencing. It is a fast and universal way of converting RAPD markers into stable markers. This revised version was published online in July 2006 with corrections to the Cover Date.     

天山云杉人工更新速生技术研究

天山云杉（Ｐｉｃｅａ ｓｃｒｅｎｋｉａｎａ ｖａｒ．ｔｉａｎｓｃｈａｎｉｃａ）天然分布区的下限海拔１４５０～１８００ｍ,进行速生丰产造林试验,结果表明,灌丛地横向割灌,纵向割灌和丛植３种处理效果显著;灌坐地和欧洲山杨（Ｐｕｐｕｌｕｓ ｔｒｅｍｕｌａ）皆伐地采用大穴整地和丛植,这２种立地类型１５ａ生的天山云杉幼树树高分别比ＣＫ高出４０．０％和４６．５％,天山云杉在不同立地类型高生长的优劣顺序为灌丛地     

禾顶囊壳小麦变种对草坪禾草的致病性研究

应用人工接种法测定了禾顶囊壳小麦变种中国菌系对草地早熟禾、多年生黑麦草、匍茎剪股颖、高羊茅、硬羊茅和狗牙根等6种草坪禾草24个品种的致病性。结果表明,该菌对供试各草种都能正常致病,引起典型全蚀病症状。大多数供试品种的病根率和病根严重度都很高,属于感病类型,仅匍茎剪股颖的绿宝石品种具有中度抗侵入性和高度抗侵染性,高羊茅Shorter品种和硬羊茅参试品种具有中度抗侵染性。由于该菌引起的小麦全蚀病在我国分布广泛,可以提供大量菌源侵染草坪禾草,从而对草坪构成严重威胁。     

云南古茶树（园）遗传多样性的ISSR分析

云南省保存有20多万亩古茶园,这些古茶树（阿萨姆变种Camellia sinensis var. assamica）种质资源可能含有各种优良基因,对未来茶树良种选育有重要意义。本研究采用ISSR分子标记技术对云南省十个有代表性的古茶园遗传多样性进行分析,十个居群的多态位点百分率（P）为56.5%~90.9%;Nei’氏遗传距离（He）居群平均是0.281,阿萨姆变种水平内是0.461;Shannon多样性指数(Ho)居群平均是0.418,阿萨姆变种水平内是0.653。而居群间遗传分化系数Gst=0.391,和Shannon多样性指数分析（36.0%）和AMOVA分析结果（39.7%）相一致,说明阿萨姆变种60.9%的遗传变异来自居群內的个体间,39.1%的遗传变异来自居群间。研究结果揭示阿萨姆变种居群遗传多样性高,居群间遗传变异存在中度的遗传分化,这可能是由于茶树种内高度异交的特性和生境片段化所致。基于观察到的居群遗传信息,建议采取就地保护和迁地保护的保护策略。     

樟子松在西北干旱沙区的蒸腾日变化

在典型干旱沙区的甘肃省民勤治沙站分别测定人工栽植的4 a、9 a和20 a樟子松8月份蒸腾强度的日进程.结果表明,9 a以上樟子松的蒸腾强度在午前随光强和气温而上升,午后下降.以当天的日平均蒸腾强度计,20 a(16.30 mmol·m-2·s-1)>4 a(14.14 mmol·m-2·s-1)> 9 a(12.51 mmol·m-2·s-1).4 a、9 a和20 a樟子松的日均水分利用效率分别为0.168 1 μmol·mol-1、0.392 6 μmol·mol-1、0.092 9 μmol·mo     

在蒙导条件下转bar基因水稻与无芒稗间的基因漂移

以转基因水稻Y0003和99-t为父本,无芒稗为母本,在蒙导条件下研究转基因水稻与无芒稗间潜在的基因漂移可能性。用光学显微镜观察了用不同方法（紫外灯照射,反复冻融,黑暗放置）制备的蒙导花粉蒙导条件下转基因水稻花粉在无芒稗柱头上的萌发生长情况,并与无芒稗自花授粉的情况相比较。结果表明,在供试的所有蒙导花粉蒙导条件下,两种转基因水稻的花粉在无芒稗柱头上虽能萌发,但花粉管扭曲成各种形状而不能进入无芒稗柱头。与无芒稗自花授粉的花粉萌发生长有极明显的差异。杂交也不结实。说明蒙导花粉不能克服转基因水稻和无芒稗的不亲和性,转基因水稻与无芒稗间基因漂移的可能性极小。     

Epoxysesquithujene, a novel sesquiterpenoid from Valeriana hardwickii var. hardwickii

Epoxysesquithujene, a new sesquiterpene epoxide has been characterized in the essential oil of Valeriana hardwickii var. hardwickii on the basis of chemical reactions and extensive NMR data. Fourteen other terpenoids have also been identified on the basis of GC-MS.     

A new isoflavone glucoside from Astragalus membranaceus var. mongholicus

A new isoflavone glucoside (1) was isolated from the roots of Astragalus membranaceus var. mongholicus. Its structure was elucidated by spectroscopic methods.     

银柴胡主要病虫害研究初报

（1宁夏绿苑沙生药用植物研究所,灵武 751410;2宁夏农科院植保所,银川 750002）