不同果袋对油梨果实品质及脂肪酸成分的影响

以海南本地3个油梨品系为试材,选取2种不同类型果袋(白色纸袋和外黄内黑牛皮纸袋)进行油梨果实套袋处理,以不套袋作为对照,在套袋后100 d,油梨成熟时采集样品,进行果实外观和内在品质的测定.观察并测定套袋对油梨果实品质和脂肪酸成分的影响.结果表明,外黄内黑牛皮纸袋套袋处理后的果实表皮变黄,白色纸袋套袋处理后的果皮颜色与...     

欧米伽膳食与热带木本油脂

概述了ω-3膳食对人体健康的研究动态,介绍了橡胶种子、油梨、澳洲坚果等富含ω-3脂肪酸与油酸的热带作物油料,是人们摄取ω-3脂肪酸及大量油酸的新资源。     

Inhibition of flowering of Mexican- and Guatemalan-type avocados under tropical conditions

Avocado trees of a range of cultivars growing in Darwin, northern Australia (average yearly maximum 33°C, minimum 23°C), were observed for flower and shoot development. Terminal buds of the cultivars ‘Fuerte’, ‘Rincon’ and ‘Edranol’ sampled in July were not floral. Buds which did not burst were sampled in September and they contained developing flowers with perianth primordia. Vegetative extension growth resulted from laterals proximal to the inhibited terminal buds.Avocado trees of the cultivars ‘Fuerte’ and ‘Hass’ which had initiated floral buds were transferred to controlled environment chambers with 33°C day, 23°C night ($\text{33}\text{23}$) or 25°C day, 15°C night ($\text{25}\text{15}$) with a 12-h photoperiod and photon flux density of 400 μmol m^?2 s^?1 (400–700 nm). At $\text{33}\text{23}$ the trees had fewer flowers and a shorter flowering period than at $\text{25}\text{15}$. Inhibited floral buds and lateral vegetative extension resulted at $\text{33}\text{23}$, as observed in northern Australia. The unburst buds had developing flowers with perianth and stamen primordia.The controlled environment experiments showed that the abnormal flushing behaviour of Mexican- and Guatemalan-type avocados growing in northern Australia was due to high temperature. Floral development was inhibited at the stage of stamen differentiation.     

Genetic relationships of avocado (Persea americana Mill.) using RAPD markers

RAPD (randomly amplified polymorphic DNA) analysis was carried out on 16 accessions representing the three ecological races of avocado (Persea americana Mill.), and one accession of P. schiedeana Nees. Twenty two preselected primers produced 133 polymorphic DNA fragments in the RAPD assay of the avocado accessions. One primer was identified which could differentiate each of the avocado accessions. Potentially race-specific markers for each of the Mexican, Guatemalan, and West Indian races, have been detected. A Jaccard's similarity coefficient matrix was generated and a dendrogram constructed using UPGMA (unweighted pair-group method of arithmetic averages) cluster analysis. Percentage similarity between avocado accessions ranged from 46% to 85%. The lowest similarity (between 22% and 29%) was revealed between P. schiedeana and any P. americana accession. Average similarity within races of avocado was 75% for the Mexican race, 71% for the West Indian race and 73% for the Guatemalan race. Average similarity between races ranged from 53% to 58%. The dendrogram identified three groups, representing the races of avocado. These results are in concordance with the present classification of avocado into three subspecies (varieties) of P. americana, namely drymifolia, americana, and guatemalensis, corresponding to the Mexican, West Indian and Guatemalan races, respectively, and confirm the separate species status of P. schiedeana. We conclude that RAPD markers may be useful for the classification of avocado and for the assessment of genetic diversity of avocado germplasm. This revised version was published online in July 2006 with corrections to the Cover Date.     

油梨果肉DNA提取方法的比较

为了获取高质量的油梨果肉DNA,以油梨果肉为试材,比较改良SDS法、改良CTAB法和试剂盒法对油梨果肉DNA的提取效果。结果表明：上述3种方法均可从油梨果肉中提取DNA,但改良SDS法与改良CTAB法所获得的DNA浓度都在600 μg/mL以上,纯度(OD260nm/OD280nm)均在1.8左右,纯度高且完整性较好,可用于未来分子标记分析。     

世界油梨产销发展概况及前景

分析了2004—2009年世界油梨栽培、产量的状况,并具体研究了世界油梨进出口贸易的情况,针对当前的油梨产业发展前景作了分析研究。     

Field evaluation of systemic imidacloprid for the management of avocado thrips and avocado lace bug in California avocado groves

BACKGROUND: The efficacy of systemic applications of imidacloprid for the management of avocado thrips and avocado lace bug was determined in field trials. Following insecticide treatment by chemigation, leaves of appropriate age for each insect were sampled over a 6 month period and used for bioassays. Imidacloprid residues were measured by ELISA in leaves used for bioassays to determine concentrations of insecticide that were toxic to both pests. RESULTS: The uptake of imidacloprid into treated trees was extremely slow, peaking in the current year's leaf flush at only 8 ng cm^?2 leaf tissue after 15 weeks. Avocado thrips mortality in bioassays with young flush leaves, the preferred feeding substrate for this insect, was minimal, indicating that imidacloprid concentrations were below threshold levels needed for effective control. Residues present in older leaves, which are preferred by the avocado lace bug, were higher than in young flush leaves, and provided good control of this pest. Probit analysis of bioassay data showed that the avocado lace bug (LC₅₀ = 6.1 ng imidacloprid cm^?2 leaf tissue) was more susceptible to imidacloprid than the avocado thrips (LC₅₀ = 73 ng imidacloprid cm^?2 leaf tissue). CONCLUSIONS: In spite of the slow uptake of imidacloprid into avocado trees, the levels of imidacloprid would be sufficient to control avocado lace bug infestations. In contrast, the slow uptake would be problematic for avocado thrips control because inadequate levels of insecticide accumulate in new flush foliage and would allow avocado thrips populations to build to levels that would subsequently damage developing avocado fruit. Copyright © 2010 Society of Chemical Industry     

鳄梨中主要功能成分及其功能特性研究进展

综述了鳄梨果实主要功能成分及其功能特性研究进展,着重阐述了鳄梨中脂肪酸、维生素、膳食纤维、类胡萝卜素、多酚类物质、谷胱甘肽的生理活性及其功能特性,旨在为进一步开发利用中国鳄梨资源提供参考。     

油梨愈伤组织诱导及分化研究

摘要：[目的]研究不同激素及外植体类型对‘哈斯’油梨（Persea Americana Mill.cv.Hass）愈伤组织诱导及分化的影响,筛选最佳诱导条件和外植体。[方法]通过间接器官发生途径。主要探讨（1）单一激素萘乙酸（1-Naphthylacetic acid,NAA）、2,4-二氯苯氧乙酸（2,4-dichlorophenoxy acetic acid,2,4-D）;6-苄氨基腺嘌呤（6-Benzylaminopurine,6-BA）分别与2,4-D和NAA 结合时对‘哈斯’油梨叶片愈伤组织的诱导效应。（2）不同外植体（叶片、叶柄、茎尖、茎段）在相同条件下（基本培养基：MS+1 mg/L 2,4-D+0.5 mg/L 6-BA+0.1NAA mg/L）的愈伤组织诱导效应。（3）单一激素 6-BA（或与NAA结合）对油梨愈伤组织芽分化的效应。[结果]结果表明：以MS为基本培养基,（1）添加1.0 mg/L 2,4-D/NAA,其诱导效果最佳,诱导率分别为45.3%和20.2%;但NAA诱导的愈伤质地较佳。（2）1 mg/L NAA与1.0 mg/L 6-BA结合,诱导效果较好,其诱导率最高可达84%。（3）诱导愈伤组织的最适外植体为茎段,其诱导率≥72.8%。叶柄次之,叶片和茎尖较差。[结论]综上,不同激素种类及其浓度和外植体类型对‘哈斯’油梨愈伤组织诱导影响显著。最佳诱导培养基为MS+1.0 mg/L NAA+1.0 mg/L 6-BA+30 g/L蔗糖+7g/L琼脂。愈伤组织诱导最佳外植体为茎段,但诱导形成的愈伤组织难以分化出芽。     

Implementation of integrated pest management in Israel

Supervised control programs were initiated by the Extension Service in the deciduous orchards of Upper Galilee and the Golan almost 20 years ago. The integrated pest management (IPM) project on fruit crops and vines, launched as a systematic state-wide program in 1991, covered 23% of the total acreage at the end of 1996. The program has reached a critical mass and generates a steady demand for this new kind of advisory service. The project has set the right pattern for intensive and continuous collaboration among research, extension and grower. The program has been successful in reaching out to growers with the help of a newly formed group of local and regional pest scouts; the field-level implementation is the responsibility of the extension system. A reduction of approximately 30% in the use of pesticides has been achieved. The project prepares the ground for environment-friendly and sustainable cropping systems, generating produce competitive on both the local as well as foreign markets. The program on indoor vegetables, flowers, herbs and spices initiated in 1992, had to address first the problem of the sweetpotato whitefly. The field program methodology relies on the establishment of model farms and plots. The model plots are used to examine supervised control scenarios which could, in turn, be diffused to all growers. A 30-50% reduction in the use of pesticides was achieved on the model farms. The program represents an integration of supervised control, fully fledged IPM, and biological control practices. The program on corn and cotton covers the entire acreage under these two crops. The cotton program is supported by an integrated resistance management component. Three area-wide pest management programs were initiated: in the Arava and Bet She’ an valleys, and in the Golan.