桃新品种——“北农早艳”、“北农二号”

培育过程:我们根据1956—57年北京郊区桃品种的调查情况,自1958年开始桃的育种。经过1958、60—63年的杂交工作,定植了一批杂种实生苗。先后从中初选出十多个优良单系。这些单系有的在北京郊区试种,有的引入上海、江苏、山西、四川等地试种。十多年来,其中二个单系已有小片生产果园或已扩大试种。1979年又经过较全面的鉴定,分别定名为北农早艳(原名6—25)与北农二号(原代号60—23—2)。     

鸡公山野生木本蔬菜资源调查

木本蔬菜绿色食品,营养价值高,开发潜力大。于2008年对鸡公山野生木本蔬菜资源进行调查,结果表明鸡公山有野生木本蔬菜植物34科74种,并对其开发利用提出建议。     

Direct evidence of Hymenoscyphus fraxineus infection pathway through the petiole‐shoot junction

The symptoms of ash dieback caused by the fungus Hymenoscyphus fraxineus include wilting of the foliage followed by dieback of shoots, twigs and branches. Necroses in shoots are assumed to develop after infection through leaf petioles; however, clear evidence of this infection pathway has not yet been provided. Considering the multiple pathogen genotypes in dead ash petioles, we aimed to obtain a spatial overview of all H. fraxineus genotypes colonizing individual shoots and their corresponding petioles before leaf shedding to acquire precise information about the infection biology of H. fraxineus and its ability to cross the petiole‐shoot junction. Individual genotypes of H. fraxineus were characterized by the analysis of microsatellites using DNA extracted directly from petiole segments or cultures isolated from the segments. We detected 150 different multilocus genotypes in 10 analysed shoots and their respective petioles; the highest number of genotypes was eight for a single petiole and three for a single shoot. The genotypes of most shoot lesions were identical to particular genotypes from the proximal segments of petioles, implicating the main pathway of shoot infections. To test whether the amount of colonized substrate or intraspecific competition have an effect on successful infection, genotypes that reached the most proximal end of the petioles were scored for the number of invaded petiole segments and for the number of other H. fraxineus genotypes co‐occurring in the segments. However, the extent of colonization of the scored genotypes and intraspecific competition with other H. fraxineus strains did not influence pathogen success in entering the shoot. This study confirms that the majority of ash shoot infections are caused by genotypes of H. fraxineus originating from petioles. Compared to petioles, the frequency of shoot colonization as well as number of H. fraxineus genotypes in shoots was much lower.     

Species-specific responses to environmental stress on germination and juvenile growth of two Bolivian Andean agroforestry species

Integrating native trees in farmland can support soil, water and biodiversity conservation. This is particularly important in regions characterized by long periods of drought and soil erosion, such as the Bolivian Andes, where agroforestry with native woody species is rarely applied. Better knowledge on the effects of environmental stress on propagation and establishment of such native plants is needed to optimize their cultivation. In our study, we tested the effects of temperature and scarification on seed germination, and assessed seedling survival and juvenile growth of two potential agroforestry species (Prosopis laevigata var. andicola, Schinus molle) under diverse soil and water conditions. Temperatures above 30 °C accelerated germination, but they increased fungi infestation in the case of S. molle. The application of acid and mechanical scarification significantly improved the germination capacity of P. laevigata var. andicola. Medium to high moisture levels in sand provided the most favourable conditions for plant growth. S. molle was more sensitive to dry and P. laevigata var. andicola more vulnerable to water-saturated clay loam. Mulching enhanced the survival and growth of S. molle juveniles, but increased P. laevigata var. andicola’s growth in sand and dry soils only. Our results may facilitate guidance on improving propagation of these two potential agroforestry species under environmental stress conditions. More generally, our study shows that easily applicable treatments, such as mulching, can significantly improve the cultivation of native species, provided that their habitat requirements and limiting factors are well known. This highlights the relevance of identifying and closing such knowledge gaps for native trees and shrubs in order to promote their potential for use in agroforestry.     

漂白胶贮存性质的研究（第五报）：紫胶树脂环状组分氯化动力学的研究

研究了在中性至微碱性水溶液中ＮａＣｌＯ与紫胶树脂环状组分代表物——壳脑酸的反应。结果表明该反应为一复杂反应，除氯对双键的加成反应外，还有其它副反应，而且反应的复杂程度与反应温度有关；对主反应而言，降低ｐＨ或提高反应温度均可加速反应；反应体系中其它无效离子的存在对主反应没有阻滞作用。文章还用计算机软件模拟了主反应的动力学方程；计算出反应在ｐＨ８．５、３０～４０℃进行时的表观活化能为１９０ｋＪ／ｍｏｌ。     

松香树脂酸乙烯酯的研究（Ⅱ）：松香树脂酸乙烯酯组成与结构的研究

研究了国立特级松香树脂酸乙烯酯的组成与各组份的分子结构。结果表明国产特级松香树酸乙烯酯的主要成分是枞酸乙烯酯,长叶松酸乙烯酯和去氢枞酸乙烯酯,三者间重量比为１３：３：２,其连续在羧基上的乙烯基在核磁共振谱图中呈现为很好的ＡＢＸ系统。     

Changes in fineroot growth dynamics in response to phosphorus application in an Acacia mangium plantation in Vietnam

Fineroots (≤ 2 mm diameter) are dynamic components of the forest ecosystems and play important role in water and nutrient acquisition in forests. These roots are sensitive to forest fertilization and therefore, the response of fineroots to nutrient application would provide better understanding of the forest carbon and nutrient dynamics that will be helpful in sustainable forest management plans. Two fertilization treatments, including (1) F400: 400 g P₂O₅ (16.5%)/tree and (2) F600: 600 g P₂O₅ /tree, and F0: control (without fertilization), were applied in an Acacia mangium plantation with a planting density of 1100 trees/ha (3 m?×?3 m). The evaluation of fineroot growth across seasons showed that fertilization significantly increased production and subsequent mortality and decomposition. The total decomposition associated with F600 application was 7.95 tons ha^?1 year^?1, equaling 121% of F400 and 160% of the control. Mortality in F600 was 8.75 tons ha^?1 year^?1, equaling 111% of F400 and 198% of F0, while production in F600 was 10.40 tons ha^?1 year^?1, equaling 127% of F400 and 143% of F0. Fineroot production, mortality, and decomposition are seasonally dependent, with higher values measured in the rainy season than in the dry season. Stand basal area increment was significantly correlated with fineroot production (R²?=?0.75), mortality (R²?=?0.44), and decomposition (R²?=?0.48). This study showed that fertilization could facilitate fineroot production, which can then lead to a higher turnover of carbon and nutrients through the decomposition of the greater mass of the fineroots.

     

天然防腐剂在果蔬保鲜涂料中的应用

采用适当的方法从中草药中提取有效成分，并将其与被膜剂复合。针对各种常见水果病菌，采用平板抑菌试验筛选出５种具有显著抑菌能力的药种，进而用最低抑制发育浓度试验比较了各药种对不同病菌的抑制作用，为天然防腐剂在果蔬保鲜涂料中应用提供了依据。     

基于绿色价值链的绿色价格研究

低碳时代的到来,使得众多企业越来越关注绿色营销,而价格作为营销最重要的要素之一也自然被营销者和消费者同时关注,能否制定合理的绿色价格,对企业赢得消费者的信赖、获得良好的经济效益和社会效益都是非常重要的。笔者基于迈克尔?波特的价值链模型,阐述了绿色价值链的概念,并将绿色价值链管理引入绿色价格机制。有效的绿色价值链管理能够缩减生产成本、降低产品价格,笔者着重从绿色价值链体系中的顾客价值链、绿色回收及与绿色价值链密切相关的人力资源管理三个方面对如何降低绿色产品价格进行分析,以此获取绿色成本的竞争优势。绿色价格战略是绿色营销战略最主要的组成部分。企业通过优化内、外部顾客价值链、重视绿色回收环节以及加强对绿色人才的引进等措施来获取绿色价格的竞争优势,树立企业绿色形象。