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Journal of Earth Science 2016年第5期27卷 883-890页

作者： Mahasin Ali Khan Subir Bera Centre of Advanced Study Department of BotanyUniversity of CalcuttaKolkata-700019India Department of Botany Sidho-Kanho-Birsha UniversityPurulia 723104India

Fossil leaf remains of two new species of persea Mill., belonging to the family Lauraceae collected from the lower part of the Siwalik sediments（Gish Clay Formation of Sevok Group, Middle Miocene） of Darjeeling foothills of eastern Himalaya, are described. The new species are persea miogamblei sp. nov. and persea neovillosa sp. nov.. On the basis of leaf architecture（size, shape and venation pattern） fossil leaves described in this article closely resemble modern leaves of persea gamblei（King ex Hook. f.） Kosterm. and persea villosa（Roxb.） Kosterm.. The geographic distribution of the fossils and their modern counterparts are discussed and on that basis tropical evergreen vegetation with a warm and humid climate at the time of deposition of the Siwalik sediments is suggested in contrast to the present day tropical deciduous vegetation in this area. The present finding also suggests probable migration of these lauraceous taxa to Southeast Asia.

关键词： persea fossil leaves Middle Miocene Siwalik paleoelimate Darjeeling.

Analysis of Sesquiterpene Distributions in the Leaves, Branches, and Trunks of Avocado (<i>persea americana</i>Mill.)

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American Journal of Plant Sciences 2013年第4期4卷 922-931页

作者： Jerome Niogret Nancy D. Epsky Elena Q. Schnell Raymond J. Schnell Robert R. Heath Alan W. Meerow Paul E. Kendra Subtropical Horticulture Research Station Agricultural Research Service United States Department of Agriculture Miami USA Subtropical Horticulture Research Station Agricultural Research Service United States Department of Agriculture Miami USA.

Avocado is a commercially valuable fruit crop cultivated in tropical and subtropical climates throughout the world. Taxonomists recognize three horticultural races of avocado, consisting of Mexican (persea americana var. drymifolia), Guatemalan (P. americana var. guatemalensis), and West Indian (P. americana var. americana) varieties. Published research that attempted to differentiate among the horticultural races by using leaf chemistry found that sesquiterpene content was only useful for discrimination of pure Mexican from Guatemalan and West Indian, but not to distinguish between Guatemalan and West Indian races. This study presents a sampling method for analysis of sesquiterpenes from avocado leaf, branch and trunk samples. Our results indicate that sesquiterpene content from leaves and small diameter branches (2.5 cm) was highly variable;however, sesquiterpenes were much less variable within wood from larger diameter branches and trunk samples, providing information representative of avocado varietal differences. In addition to chemotaxonomic applications, information on sesquiterpene content of avocado wood is needed for identification of host-based attractants for a new avocado pest, the redbay ambrosia beetle (Xyleborus glabratus). This insect vectors a fungal pathogen that causes laurel wilt, a lethal vascular disease that currently threatens avocado production in south Florida, USA. Females of X. glabratus identify appropriate host trees based on emissions of terpenoids, particularly α-copaene. Our results are discussed in terms of how proximo-distal distributions of sesquiterpenes may function as host-location cues by this invasive wood-boring pest.

关键词： Avocado persea americana Sesquiterpenes α-Copaene Redbay Ambrosia Beetle Xyleborus glabratus

Genetic diversity of <i>persea bombycina</i>from goalpara district of Assam, India

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Advances in Bioscience and Biotechnology 2012年第1期3卷 20-24页

作者： Azizur Rahman Bhaben Tanti Gajen Chandra Sarma Jatin Kalita Department of Botany Gauhati University Assam India Department of Zoology Gauhati University Assam India epartment of Sericulture Government of Assam Khanapara Guwahati India

Assam of the northeastern region of India is unique in terms of its rich biodiversity and multiple ethnicity of its people. The impact of the resultant socio-religio-cultural diversity is also reflected in the diverse traditional ways of silkworm farming. We report the genetic diversity of persea bombycina “Som” from different locations of Goalpara district of Assam, India, where random amplified polymorphic DNA (RAPD) marker was used in this study. RAPD analyses of ten genotypes of “Som” from Goalpara district of Assam, India with B19 RAPD primer generated 86 bands, showing an average of 8.6 bands per sample and 30.2% (26 bands) of these were polymorphic. The number of bands per accession ranged from 5 to 10 with a mean of 8.6 and the size range of the amplified bands was 250 - 6000 bp. In a UPGMA phenetic dendrogram based on Jaccard’s coefficient, the P. bombycina accessions showed a high level of genetic variation, as indicated by genetic similarity and revealed 10 “Som” genotypes in to three major clusters. This study may be useful in identifying diverse genetic stocks of P. bombycina, which may then be conserved on a priority basis. The RAPD primer used in this study was able to distinguish all the 10 genotypes of “Som” plants, which can be used to assess genetic diversity.

关键词： persea bombycina Genetic Diversity Molecular Markers RAPD Analyses

Genetic Transformation Studies on Avocado Cultivar “Hass” (persea americana)

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American Journal of Plant Sciences 2012年第9期3卷 1225-1231页

作者： Muhammad F. Ahmed Arumugam S. Kantharajah Paul Holford Department of Agricultural Sciences American University of Beirut Beirut Lebanon University of Western Sydney South Penrith DC Australia

The use of traditional breeding for improvement of avocado cultivars is time consuming, hence other methods such as genetic transformation by Agrobacterium is indispensable to adopt. The strain GV3850/pBI121gave best transformation outcome compared to five other binary vectors (AGL1/pCGP904;AGL1/pBI121;GV3850/pCGP904;LBA4404/pCG-P904 and LBA4404/pBI121) under different pH and acetosyringone concentrations. The optimal condition for reliable transformation was by using 200 μM acetosyringone and a pH of 5.2. Transformed embryonic shoots co-cultivated with GV3850/pBI121 were tested using the histochemical x-gluc assay. Further analysis was conducted by polymerase chain reaction using specific primers for the reporter gene (GUS).

关键词： Avocado persea Binary Vectors GUS Reporter

Impact of Oriental Fruit Fly Postharvest Treatments on Avocado

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American Journal of Plant Sciences 2017年第3期8卷 549-560页

作者： Daniel Carrillo Amy Roda Clara Sarmiento Armando Monterroso Xiqui Wei Teresa I. Narvaez Jeff Crawford William Guyton Alan Flinn Don Pybas Woodard D. Bailey Department of Entomology and Nematology Tropical Research and Education Center University of Florida-Institute of Food and Agricultural Sciences Homestead FL USA United States Department of Agriculture-Animal and Plant Health Inspection Service Center for Plant Health Science and Technology Miami FL USA Brooks Tropicals LLC. Homestead FL USA Avocado Administrative Committee Homestead FL USA

The detection in August 2015 of the Oriental Fruit Fly (Bactrocera dorsalis Hendel, Diptera: Tephritidae) in the Redland area in Miami-Dade County, Florida triggered a quarantine that restricted the movement of fruit fly host material in an approximately 99-square mile (256-square kilometer) area. The quarantine affected 4000 acres of fruit bearing commercial avocado groves. Approved post-harvest treatments for B. dorsalis and avocado included in the USDA Treatment Manual were acceptable for immediate certification and movement of fresh avocados from the quarantine area. However, it was unknown if Florida avocados would meet quality standards (US combination grade) after the treatments. Three post-harvest treatments that combine methyl bromide fumigation and cold storage periods were tested on six avocado varieties from Florida. The treatments differed in the durations of the fumigation and cold treatment periods. A seven day transit period at 8.3°C (47°F) was added to account for the time when the fruit leaves the packing house until it is sold by retailers. None of the six varieties had met the US combination grade after the treatments and transit period. Treated fruit exhibited both internal (pulp) and external (skin) damage. Damage was attributed to the fumigation component of the treatment, but the six varieties tolerated the cold portion of the treatment. Damage by fumigation ranged from 26% - 100%. In general, the longer the fumigation period the worse the effect. The need for alternative post-harvest treatments for Florida avocados is discussed.

关键词： Bactrocera dorsalis persea americana Postharvest Quarantine Fumigation

Avocado and Cardiovascular Health

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Open Journal of Endocrine and Metabolic Diseases 2015年第7期5卷 77-83页

作者： Camila Weschenfelder Júlia Lorenzon dos Santos Priscilla Azambuja Lopes de Souza Viviane Paiva de Campos Aline Marcadenti Postgraduate Studies Program in Cardiology Instituto de Cardiologia/Fundacao Universitária de Cardiologia do Rio Grande do Sul (IC/FUC) Porto Alegre Brazil Department of Nutrition Federal University of Health Sciences of Porto Alegre (UFCSPA) Porto Alegre Brazil

Avocado is a fruit which had a caloric density of 1.7 kcal per gram and a half unit (~70 g) is composed by 114 kcal, 4.6 g of fibers, 345 mg of potassium, 19.5 mg of magnesium, 1.3 mg of vitamin E and 57 mg of phytosterols. Approximately 75% of fiber’s avocado contents are considered insoluble and 25% are soluble. The avocado contains lipids that consist of 71% from monounsaturated fatty acids (MUFA), 13% from polyunsaturated (PUFA) and 16% from saturated fatty acids (SFA). Recent researches have shown that avocado may improve hypercholesterolemia and may be useful in the treatment of hypertension and type 2 diabetes mellitus (T2DM). This way, avocado plays an important role in the cardiovascular health. This review summarizes the potential benefits of avocado consumption in the prevention of cardiovascular risk factors and metabolic diseases.

关键词： persea Diabetes Mellitus Type 2 Dyslipidemias Nutritional Status Blood Pressure