鹅掌楸种源遗传变异和选择评价

在中国鹅掌楸全分布区内抽样15个种源，于长江中下游5省区按统一试验设计营造种源试验林，7年生时全面测定其树高（H）、胸径（DBH）、冠幅（RC）等主要生长性状，进行遗传6变异分析，结果表明：中国鹅掌楸生长性状在种源间存在显著的遗传差异，地点间差异极显著，种源对环境反映灵敏，种源与地点间存在明显的交互作用，H、DBH和材积（V）的广义遗传力分别为0.503、0.526、0.521，受较强的遗传控制；RC受遗传控制程度相对较低（H^2=0.301)。相继进行了遗传稳定性、生长适应性分析和幼成龄相关分析，分析结果为种源选择和评价提供了理论依据，多点综合选择选出黎平、伤痛永两个优良种源，遗传增益11.8%。单点选择分别选出1-3个丰产种源，遗传增益达15.4%-51.5%。     

毛竹材材性变异的研究

通过对毛竹材纤维形态，组织比量、纤维素含量和基本的分析测定，研究了不同年龄、不同胸径、竹秆不同部位栲生性状的变异特点结果表明，竹材纤维长度主要受竹秆部位的影响，与年龄和胸径无显著相关，组织比量与年龄无显著相关，与胸径有一定相关；纤维素含量和基本密度与年龄、胸径、竹秆部位均有关系，从材性变异特点来看，经营培育小径级毛竹对制浆造纸更有利。     

Domestication of Irvingia gabonensis: 3. Phenotypic variation of fruits andkernels in a Nigerian village

Domestication of Irvingia gabonensis, a fruit tree grown in agroforestry systems in West and Central Africa, offers considerable scope for enhancing the nutritional and economic security of subsistence farmers in the region. Assessments of phenotypic variation in ten fruit, nut and kernel traits were made on twenty-four ripe fruits from 100 Irvingia gabonensis trees in Ugwuaji village in southeast Nigeria, a center of genetic diversity for this species. There were important differences between the young planted trees of this study and the older unplanted trees of a similar study in Cameroon. Significant and continuous tree-to-tree variation was found in fruit mass(69.0–419.8 g), flesh mass (59.5–388.8 g), nut mass (9.5–40.6 g), shell mass (4.9–30.9 g) and kernel mass (0.41–7.58 g); fruit length (49.2–89.3 mm) and width (46.2–100.5 mm) and flesh depth (12.9–31.4 mm), as well as considerable variation in flesh colour, skin colour, fruit taste and fibrosity. Some fruits were considerably bigger than those found in Cameroon. These quantitative results will help in the development of cultivars within participatory approaches to agroforestry tree domestication, and so promote poverty alleviation and sustainable agriculture. This revised version was published online in June 2006 with corrections to the Cover Date.     

柏木属引种研究

柏木属为常绿乔木。现已定名有24种。分布在北半球。美洲从俄勒冈到墨西哥,欧亚大陆从地中海地区到中国喜马拉雅山地。中国原产有5种。江苏从1930年以来已栽培有8个种和10多个不同种源。墨西哥柏危地马拉种源生长最快,但树冠大,干型较弯曲。墨西哥柏肯尼亚①,②,③3个种源生长快,树冠紧凑,干型通直。绿子柏和垂柏比墨西哥柏耐寒性强。本文同时介绍了柏木属的种子和扦插育苗技术。     

Monophyly and infrageneric variation of Corispermum L.(Chenopodiaceae),evidence from sequence data psbB-psbH,rbcL and ITS

Corispermum is one of the most problematic taxonomic genera in Chenopodiaceae.To understand the phylogeny and infrageneric variation of Corispermum,we sequenced the nuclear ribosomal ITS region and two chloroplast DNA regions(rbcL and psbB-psbH) of 22 species and three varieties of Corispermum and the related genus Agriophyllum.Several representative species of Salsola,Suaeda,Chenopodium,Kalidium and Camphorosma served as outgroups.Our phylogenetic trees confirm that the tribe Corispermeae is monophyletic,Corispermum and Agriophyllum have a close relationship.Corispermum is demonstrated to be monophyletic,and contains at least four clades which,consequently,are served as the foundation of the infrageneric sectional variation of Corispermum,in terms of a combination of molecular data and morphological characters.The evolution of morphological characters for fruit wing and apex,two important characters in generic classification,is consistent with the sectional division of Corispermum,especially to the East Asian and Chinese taxa.     

Taxonomy,distribution and biology of lettuce powdery mildew (Golovinomyces cichoracearum sensu stricto)

This paper reviews the taxonomy, biology, importance, host–pathogen interactions and control of lettuce powdery mildew. The main causal agent of this disease, Golovinomyces cichoracearum s.s., is an important powdery mildew pathogen of many members of the family Asteraceae. The pathogen is distributed worldwide and occurs on Lactuca sativa as well as wild Lactuca spp. and related taxa (e.g. Cichorium spp.). Powdery mildew of lettuce can be a major problem in production areas with favourable environmental conditions for disease development (dry, hot weather). The fungus grows ectophytically and appears as white, powdery growth on both the upper and lower sides of leaves. There is rather limited information on the geographic distribution of powdery mildew on wild Lactuca spp. Most L. sativa cultivars have been found to be susceptible. Large variability in virulence was confirmed and existence of different races is supposed. Resistance in L. sativa and some related wild Lactuca spp. is characterized by race‐specificity, but the genetic background of resistance is poorly understood. Sources of resistance are known in L. saligna and L. virosa. Lettuce powdery mildew can be effectively controlled by common fungicides (e.g. sulphur, myclobutanil, quinoline, strobilurins, etc.) and protective compounds (e.g. extract of neem oil, Reynoutria sachaliensis extracts). However, fungicide resistance may arise. Non‐fungicidal activators of plant systemic acquired resistance (SAR) had no direct effect on the causal agent. Future issues regarding lettuce powdery mildew research are summarized.     

新疆天山地区日照时数的气候特征

基于1961-2008年新疆天山地区23站日照时数的逐日资料,使用一元线性方程和M-K检验等统计方法,分析天山地区日照时数的时空变化特征。结果表明：①日照时数的气候分布存在明显的空间差异,呈东多西少,南多北少的分布特征。②区域平均日照时数均呈减少趋势,尤其在冬季和夏季。③四季除春季外日照时数均存在明显的年代际变化特征,...     

邢台市地下水动态变化及其致灾效应分析

根据1985-2007年的邢台地区地下水埋深数据、近10年地下水环境质量数据以及近37年的气象数据,运用arcGIS9.2,结合线性回归法、相关性分析、5年滑动平均法等,在分析地下水位动态变化的基础上,进一步分析此种变化的致灾效应.结果表明:邢台平原区浅层地下水以0.89m/a的速率下降,年内与降雨变化同步,深层地下水...     

火炬松材性变异规律的初步研究

对生长于广西南宁地区相同环境下来自美国的１８个种源１０年生火炬松的材性进行了研究。包括：材笥的种源变异。材性的地理变异模式及其与原产地气候因子的相互关系，材性因子间及其与生长因子、形态因子的相关分析。     

粗皮桉种源/家系的遗传变异

粗皮桉是生产锯材的潜力树种之一。对其进行了种源/家系早期选择试验，结果表明：2年生试验林的平均树高和胸径分别为7.69m和7.08cm，保存率为75.08%，且各指标在种源和家系水平上都存在极显著差异；树高的遗传力随树龄的增加而增大，2年生时树高和胸径的遗传力分别为26.3%和22.8%，用指数选择法选出17861等8个种批（平均树高7.82-7.93m，平均胸径6.99-7.38cm)和211等15个家系（平均树高7.80-9.43m，平均胸径8.00-8.69cm)为推荐的潜力优良材料。