Preparation and characterization of melamine-formaldehyde resin microcapsules containing fragrant oil

In this study, melamine-formaldehyde microcapsules were prepared viain situ polymerization using peppermint oil as a core material, melamine-formaldehyde as the wall material, Tween 20 as the emulsifier, and poly (vinyl alcohol) as a protective colloid. The melamine-formaldehyde microcapsules prepared in this study were then evaluated with regard to their structures, thermal properties, particle size distributions, morphologies, and release behaviors.     

Meira nashicola sp. nov., a novel basidiomycetous, anamorphic yeastlike fungus isolated from Japanese pear fruit with reddish stain

Three undescribed strains of basidiomycetous, anamorphic yeastlike fungi were isolated from Japanese pear fruits with a reddish stain collected in Tottori Prefecture, Japan. The strains are classified in a single group and assigned to the genus Meira by conventional and chemotaxonomic studies. Sequence analyses of the D1/D2 domain of 26S rDNA and internal transcribed spacer (ITS) regions indicate that the strains represent a novel species with a close phylogenetic relationship to Meira geulakonigii and M. argovae. The name Meira nashicola sp. nov. is proposed for the strains (type strain PFS 002 = MAFF 230028 = CBS 117161).     

梨实生树不同发育区的叶片细胞学研究

采用显微分光光度计和显微图像分析仪比较研究了8年生梨实生树(Pyrus pyrifliaNakai)童区和成年区叶片细胞核 DNA含量、RNA含量和细胞、细胞核面积大小的差异。梨实生树从童区向成年区转变后,叶片内细胞核DNA含量上升,细胞内RNA合成加强,细胞和细胞核面积增大;同时,叶肉组织结构分化程度提高,叶面积增大,叶片加厚。     

Parasitoids of Apiomyia bergenstammi (Wachtl) (Dipt., Cecidomyiidae), a new pest on pears, in Hatay province, Turkey

Abstract:  Studies were carried out on the galls formed by Apiomyia bergenstammi (Wa.) on buds and/or twigs of pear trees, in Yayladagi, Senköy, and Belen, Hatay province, Turkey in 2003. The pest was introduced into Hatay province at least 5 years ago. It produces one generation a year and hibernates as larvae in the galls. In Yayladagi, Senköy and Belen, 20, 18 and 5%, respectively, of buds/twigs of pear trees were attacked by A. bergenstammi . Each of the galls contained on average 9.6 ± 0.5 (range: 6–11) larval chambers. Adults were reared from galls collected at the beginning of spring, viz. A. bergenstammi emerged in the first half of April 2003, Oxyglypta rugosa Ruschka (Hym., Pteromalidae) and Torymus apiomyiae Boucek & Mihajlovic (Hym., Torymidae) (a new record for Turkey) emerged in the second half of April. Other chambers contained unemerged adults of Platygaster sp. (Hym., Platygasteridae). Natural parasitism rates obtained by dissecting 10 galls from Yayladagi and Senkoy in 2003 were: 26.6 ± 4.4% by O. rugosa and 10.0 ± 3.2% by Platygaster sp. The parasitism rate by T. apiomyiae was 16.6% as determined from the galls collected from Belen.     

Photosystem II efficiency and mechanisms of energy dissipation in iron-deficient,field-grown pear trees (Pyrus communis L.)

The dark-adapted Photosystem II efficiency of field-grown pear leaves, estimated by the variable to maximum chlorophyll fluorescence ratio, was little affected by moderate and severe iron deficiency. Only extremely iron-deficient leaves showed a decreased Photosystem II efficiency after dark adaptation. Midday depressions in Photosystem II efficiency were still found after short-term dark-adaptation in iron-deficient leaves, indicating that Photosystem II down-regulation occurred when the leaves were illuminated by excessive irradiance. The actual Photosystem II efficiency at steady-state photosynthesis was decreased by iron deficiency both early in the morning and at midday, due to closure of Photosystem II reaction centers and decreases of the intrinsic Photosystem II efficiency. Iron deficiency decreased the amount of light in excess of that which can be used in photosynthesis not only by decreasing absorptance, but also by increasing the relative amount of light dissipated thermally by the Photosystem II antenna. When compared to the controls, iron-deficient pear leaves dissipated thermally up to 20% more of the light absorbed by the Photosystem II, both early in the morning and at midday. At low light iron-deficient leaves with high violaxanthin cycle pigments to chlorophyll ratios had increases in pigment de-epoxidation, non-photochemical quenching and thermal dissipation. Our data suggest that pH could be the major factor controlling thermal energy dissipation, and that large (more than 10-fold) changes in the zeaxanthin plus antheraxanthin to chlorophyll molar ratio caused by iron deficiency were associated only to moderate increases in the extent of photoprotection.This revised version was published online in October 2005 with corrections to the Cover Date.     

人工低温对滇中砀山酥梨休眠芽和枝的效应

建立大田温栅,以不同的人工低温量（冷温小时数分别为６００ｈ、９００ｈ、１２００ｈ）处理滇中砀山酥梨休眠芽和枝,分别将枝条嫁接到温棚中,调查芽的萌动与发育状况,并检测不同的低温量导致芽和枝发生的生理生变化。结果表明,不经冬季低温处理的砀山酥酥梨花芽自然不能解除休眠,６００ｈ低温量基本可解险砀山酥梨花芽休眠,９００ｈ低温量使休眠芽的总萌发率、花芽萌动率均达最高值,１２００ｈ低 一反而使休眠芽的总萌发率     

香梨果实成熟衰老过程中4种内源激素的变化

以库尔勒香梨[白梨(PyrusbretschneideriRehd.)的变种]为材料,在果实生长发育、成熟衰老期间检测内源IAA、GA3、ABA、乙烯含量变化规律及其相互关系。结果表明果实发育初期IAA、GA3、ABA含量最高,有利于幼果坐果;CA3与ABA的比值变化对果实迅速膨大起关键作用;高浓度GA3对阻抑叶绿素分解起明显作用;果实成熟衰老期间,IAA含量与乙烯释放速率呈方向相同的变化;在此期间GA3含量变化与乙烯释放变化相反。     

Purification partielle et propriétés des amylases de la poire

Three amylases E1, E2 and E3 have been extracted from Passe-Crassane pears pulp and partially purified. A good extraction of these enzymes is obtained only with non ionic detergents. Furthermore, solubilization of amylase E1 needs the use of these compounds. Separation of the 3 amylases is obtained by chromatography on Sephadex G100. E1 and E2 are β-amylases whereas E3 is an α-amylase. The first two have similar kinetic properties and interconversion of one form into the other is possible. It is suggested that the insoluble form E1 is the result of the association of β-amylase E2 with other compounds present in the fruit.     

SSR分子标记在梨种质资源研究中的应用

SSR（simple sequence repeat）标记,又称微卫星标记,具有多态性高、重复性好、共显性、检测简单等优点,在果树树种的多样性、品种和亲缘关系鉴定等方面得到了广泛应用。就近年来SSR分子标记在梨种质资源研究上的应用,综述了SSR分子标记的筛选与开发研究、种质资源的分类与多样性研究、品种鉴别与亲子鉴定研究以及重要性状的SSR标记与定位研究进展,并对存在问题进行分析和展望,旨在为相关研究工作提供参考。