植物精油在果蔬保鲜中的应用

植物精油多提取于香辛料及中草药植物的花、叶、茎、根或果实,具有显著的抑菌效果,且安全无毒,是一种理想的天然果蔬保鲜剂。通过对植物精油的抑菌活性、果蔬防腐保鲜的作用及其机理等方面进行综述及分析可知,植物精油的开发利用必将迎来更加广阔的前景。     

Environmental Education in the Condor Bioreserve

Abstract

Effective conservation rests on an educated population. This chapter describes the status of environmental education programs in the Condor Bioreserve (CBR), Ecuador and makes recommendations for expansion of educational efforts. The major programs that are currently in place include the community park guard system, the Andean Bear Project, and workshops and networks established by the US Department of Interior and The Nature Conservancy. Most environmental education in the CBR is focused on community participation in natural resource management, and there is a relatively small amount of attention devoted to programs for teachers and children. Major recommendations include defining common goals, increasing environmental education efforts in schools, offering teacher training, developing monitoring and assessment protocols, and expanding educational efforts outside of the CBR. The paper links recommendations for improvements in environmental education in the CBR to lessons learned through research and education programs elsewhere in the world.     

气质联用仪测定水果中的甲基异柳磷农药残留

建立了水果中甲基异柳磷农药残留的气相色谱-质谱仪检测方法。水果样品用乙腈匀浆提取,盐析离心后,取上清液,经固相萃取柱净化,用乙腈-甲苯溶液(3+1)洗脱农药及相关化学品,溶剂交换后用安捷伦7890B-7000D气质联用仪检测。结果表明,空白样品加标回收率范围为88.6%～112.8%,相对标准偏差小于10%,甲基异柳磷的检出限为0.001 mg/kg。该方法操作简便、准确、灵敏、重现性强、回收率高、基质干扰少,适用于农药残留量的测定。     

库尔勒香梨突萼、脱萼及宿萼果实品质与香气的比较

为研究库尔勒香梨突萼、脱萼、宿萼3种类型果实的品质差异,对其单果质量、可食率等12种果实品质指标、矿质元素及香气成分含量进行测定。结果显示：突萼果的单果质量及果皮花青素含量显著优于脱萼果与宿萼果;脱萼果的石细胞含量显著低于突萼果与宿萼果,且可溶性固形物含量与可溶性糖含量均优于其他两种类型的果实;宿萼果的可食率及果皮叶绿素含量显著高于突萼果与脱萼果。突萼果N元素含量显著高于脱萼果与宿萼果,脱萼果的Ca、Mg、Zn元素含量显著高于突萼果与宿萼果、P元素含量显著低于突萼果与宿萼果。从库尔勒香梨中检测到39种香气成分,以醛类最高,香气物质总含量排序为脱萼果>突萼果>宿萼果,且脱萼果中香梨的主要特征香气成分含量也显著高于突萼果与宿萼果;突萼果和脱萼果果实香气成分中以(E)-2-己烯醛含量最高,宿萼果果实中含量最高的主要香气成分为正己醛。     

微生物素在果蔬采后保鲜中的应用进展

微生物素在果蔬采后保鲜中有重要的应用价值,但目前实际应用在果蔬采后保鲜领域中的并不多。本文分析了目前已经应用到果蔬保鲜领域的微生物素种类,有乳酸链球菌肽、溶菌酶、木霉发酵液等,分析了其抑菌保鲜原理及研究现状;并结合微生物素的特点,提出了微生物素在未来果蔬采后保鲜中的发展趋势,即面对冷藏技术使用不完善的现象,可以开发利用更多的微生物素种类,如纳他霉素、红曲霉素、短梗霉多糖等,为今后果蔬采后保鲜领域的健康可持续发展提供参考。     

Compatibility of crosses between gene pools and evolutionary classes in the common bean (Phaseolus vulgaris L.)

The extent of genetic divergence between the Mesoamerican and Andean gene pools and between evolutionary classes (wild, landrace and bred) in Phaseolus vulgaris was explored. The compatibility of crosses was assessed by the frequency with which pollination was successful and the number of seeds in the resulting pod. Mesoamerican genotypes were more effective as pollinators than Andean genotypes, regardless of the gene pool of the female parent. Though certain individual genotypes were more easily pollinated by genotypes of one or other of the gene pools, there was no consistent tendency for pollinations between genotypes within a gene pool to be more successful than those between gene pools. In crosses among wild and landrace genotypes, the landrace genotypes were more easily pollinated. In those among wild and bred genotypes, the bred genotypes were more effective as pollinators, and the number of seeds per pod was greater in crosses between the evolutionary classes than in those within classes. In crosses among landrace and bred genotypes, those within evolutionary classes had higher success rates than those between classes (47.2% vs. 38.9%), and produced more seeds per pod. However, these results do not represent a major barrier between the evolutionary classes. The hypothesis that dwarf-lethal incompatibility in inter-gene pool crosses is controlled by two complementary dominant genes (the DL-gene hypothesis) was tested by comparing the numbers of normal and abnormal plants in the progeny of three-way crosses, and the ratios obtained were consistent with the hypothesis. It is concluded that there is no biological barrier between the two gene pools and that they are distinct because, by accident of ancestry, they are located in geographically isolated and ecologically distinct areas, with different cultural practices and preferences. Research programmes aimed at transferring desirable traits between the gene pools should therefore be encouraged.     

果实类型分类探讨

根据多年来在教学和科研工作中的体会,参考了国内外有关文献资料,从解剖构造入手,以果皮的来源和果实成熟时果皮的形态为基础,对被子植物３０种果实类型的划分作了探讨,对部分教科书中某些不完整或易被误解的概念作了补充和更正。文末还列出了果实分类检索表。     

施用硼肥对杏树落花落果的影响

Effect of boron on falling of prunes (Prunus mune,Sieb,et Zucc) was studied by applying 50g borate per tree into soil on december 15,1993(soil-B) and spraying leaves leves evenly twice with 1.5g kg^-1 borate solution on March 1 and 8,1994(spray-B) on the soil with 0.28mg kg^-1 rapidly available B.Compared with no borate treatment (CK),B concentrations of leaves,short branches and flowers were higher and the percentage of flower and fruit drop was lower in the treatments of soil-B and spray-B.B fertilizer increased B concentrations in flowers,leaves and short branches,promoted pollen germination,reduced the percentage of fall of flowers and fruits of prunes,increased the percentage of fertile fruits,and thus increased yields of prunes by 46% and 34.3% in the treatments of soil-B and spray-B,respectively.It could be inferred preliminarily that if B concentration of leaves was lower than 35 mgkg^-1,the prunes should be fertilized with B.The measured leaves should be picked from branches(3-10cm in legnth)germinating from the central section of a tree crown during the last ten days of May to the early days of June.     

果实贮藏保鲜技术的研究进展

寻找安全有效的果实采后防腐、杀菌技术,已成为果实保鲜领域的重要课题之一。阐述国内外果实采后贮藏保鲜研究的最新进展,详细介绍天然果蔬保鲜剂、采后热处理、气体调控、乙烯拮抗和基因工程等保鲜方法的作用机理及应用效果,以期为延长果实贮藏期提供参考。     

腐烂柑橘厌氧发酵产沼气适宜的接种率与料液浓度组合

本文以腐烂柑橘果实为原料,通过测定厌氧发酵过程中发酵液和沼气的各项指标,研究了不同接种率与料液浓度对厌氧发酵过程的影响。结果表明,用石灰水调节pH值,尿素调节C∶N,最优组合为接种率70%(即腐烂柑橘添加量为30%),料液浓度为8%,无需二次调节pH值,产气可维持30天,TS产气率为595 mL.g-1,甲烷平均含量为50.3%。