Anatomy and lignin distribution in reaction phloem fibres of several Japanese hardwoods

Background and Aims Although tension wood formation and the structure of gelatinous fibres (G-fibres) have been widely investigated, studies of the influence of the reaction phenomenon on phloem fibres have been few and incomplete in comparison with those of xylem wood fibres. This study was undertaken to clarify the influence of stem inclination on phloem fibres using several Japanese hardwood species that produce different G-fibre types in tension wood. Methods Eight hardwood species were inclined at 30-45° at the beginning of April. Specimens were collected in July and December. The cell-wall structure and lignin distribution of phloem fibres on both the tension and opposite sides were compared by light microscopy, ultraviolet microscopy, confocal laser scanning microscopy after staining with acriflavine, and transmission electron microscopy after staining with potassium permanganate. Key Results Three types of changes were found in tension-side phloem fibres: (1) increases in the proportion of the syringyl unit in lignin in the S(1) and S(2) layers and compound middle lamella (Cercidiphyllum japonicum), (2) formation of unlignified gelatinous layers (Melia azedarach and Acer rufinerve) and (3) increases in the number of layers (n) in the multi-layered structure of S(1) + S(2) + n (G + L) (Mallotus japonicus). Other species showed no obvious change in cell-wall structure or lignin distribution. Conclusions Phloem fibres of the tree species examined in our study showed three types of changes in lignin distribution and cell-wall structure. The reaction phenomenon may vary with tree species and may not be closely related to G-fibre type in tension wood.     

琴叶风吹楠(肉豆蔻科)分类学位置再研究

琴叶风吹楠(Horsfieldia pandurifolia Hu)自1963年命名发表以来,其分类学位置一直存在争议。本文以中国野生肉豆蔻科(Myristicaceae)11个种为材料,从形态学、油脂化学和分子遗传学方面对琴叶风吹楠分类学位置进行研究。结果表明,琴叶风吹楠与H.macrocoma ssp. prainii的形态特征高度一致,与中国风吹楠属其它类群,以及红光树属和肉豆蔻属植物在形态学和油脂化学方面存在决定性差别,在分子遗传学方面存在较大差异。支持将H.pandurifolia并入H.macrocoma ssp. prainii,以H.macrocoma为模式种建立Endocomia属,琴叶风吹楠的学名变更为Endocomia macrocoma(Miq.) de Wilde ssp. prainii(King) de Wilde。     

钙试剂处理对早期榛子果实发育与成果率的影响

为探究钙试剂处理对早期榛子果实发育与成果率的影响,为榛子果实的生长发育及产量的提高提供理论依据,在榛子的盛花期进行CaCl₂及EGTA喷施处理,T1处理：浓度为20 mmol·L^-1 CaCl₂,T2处理：浓度为20 mmol·L^-1 EGTA溶液,CK处理：清水作为对照。在花后30和35 d测定果实的直径及钙的含量。在果实成熟期对果簇的果实数量及果实败育率统计。结果表明：T1处理的两品种在花后30 d幼果直径与CK处理相比分别增长了12.63%和14.13%,含钙量（Wt）分别提高了27.2%和44.63%;T2处理的幼果比CK处理分别减少了11.58%和13.04%,含钙量（Wt）分别降低9.74%和13.76%,且均达到显著差异水平。花后35 d T1处理的两品种幼果直径与CK处理比分别增长了10.94%和15.18%,含钙量（Wt）分别提高了25.13%和40.61%;T2处理的两品种幼果直径分别小于CK处理15.63%和13.39%,含钙量（Wt）分别降低26.8%和26.06%,且均达到显著差异。两品种幼果含钙量与成熟后果簇的平均果实数量呈显著正相关关系,与成熟后的平均果实败育率呈显著负相关关系。     

Intratumoral immunocytokine treatment results in enhanced antitumor effects

Immunocytokines (IC), consisting of tumor-specific monoclonal antibodies fused to the immunostimulatory cytokine interleukin 2 (IL2), exert significant antitumor effects in several murine tumor models. We investigated whether intratumoral (IT) administration of IC provided enhanced antitumor effects against subcutaneous tumors. Three unique ICs (huKS-IL2, hu14.18-IL2, and GcT84.66-IL2) were administered systemically or IT to evaluate their antitumor effects against tumors expressing the appropriate IC-targeted tumor antigens. The effect of IT injection of the primary tumor on a distant tumor was also evaluated. Here, we show that IT injection of IC resulted in enhanced antitumor effects against B16-KSA melanoma, NXS2 neuroblastoma, and human M21 melanoma xenografts when compared to intravenous (IV) IC injection. Resolution of both primary and distant subcutaneous tumors and a tumor-specific memory response were demonstrated following IT treatment in immunocompetent mice bearing NXS2 tumors. The IT effect of huKS-IL2 IC was antigen-specific, enhanced compared to IL2 alone, and dose-dependent. Hu14.18-IL2 also showed greater IT effects than IL2 alone. The antitumor effect of IT IC did not always require T cells since IT IC induced antitumor effects against tumors in both SCID and nude mice. Localization studies using radiolabeled ¹¹¹In-GcT84.66-IL2 IC confirmed that IT injection resulted in a higher concentration of IC at the tumor site than IV administration. In conclusion, we suggest that IT IC is more effective than IV administration against palpable tumors. Further testing is required to determine how to potentially incorporate IT administration of IC into an antitumor regimen that optimizes local and systemic anticancer therapy.     

Detection of the impact of early Holocene hunter-gatherers on vegetation in the Czech Republic, using multivariate analysis of pollen data

Pollen data from the Czech Republic was used to detect the early Holocene impact of hunter-gatherers on vegetation based on a selection of 19 early Holocene pollen profiles, complemented with archaeological information regarding the intensity of local and regional Mesolithic human habitation. Archaeological evidence was assigned to simple categories reflecting the intensity of habitation and distance from pollen sites. Multivariate methods (PCA and RDA) were used to determine relationships between sites and possible anthropogenic pollen indicators and to test how these indicators relate to the archaeological evidence. In several profiles the pollen signal was influenced by local Mesolithic settlement. Specific pollen types (e.g. Calluna vulgaris, Plantago lanceolata, Solanum and Pteridium aquilinum) were found to be significantly correlated with human activity. The role of settlement proximity to the investigation site, the statistical significance of pollen indicators of human activity, as well as the early occurrence of Corylus avellana and its possible anthropogenic dispersal, are discussed.     

Expression of the RNA binding proteins,Mel-N1, Mel-N2, and Mel-N3 in adipose cells

Mel-N1 (murine embryonic lethal abnormal vision [ELAV]), a mammalian homolog of Drosophila ELAV, is an mRNA binding protein of the RNA Recognition Motif family. Studies with the human homolog, Hel-N1 have supported the hypothesis that Hel-N1, and its splice variant, Hel-N2 play a role in mRNA metabolism. Thus it becomes logical to extend this hypothesis to the murine variant Mel-N1 which has been described as a neuronal protein with a minor level of expression in the testis. Our current work expands the potential function for this protein through demonstration of expression of the full-length message and splice variants in adipose tissue as well as preadipocyte and adipocyte cell lines.     

膜下滴灌水氮耦合对春玉米产量和水分利用效率的影响

采用二次回归正交设计,在移动旱棚水、肥精量控制条件下研究了土壤湿度和施氮量对春玉米产量、耗水量及水分利用效率的影响。结果表明:水氮耦合作用对玉米产量有显著的影响(P0.05)。产量随着土壤湿度和施氮量的升高呈先增大后减小的趋势。分析产量模型可知,当土壤湿度为田间持水量的65%~70%、施氮量为462 kg·hm-2时,玉米产量可达15142.5 kg·hm-2。玉米不同处理阶段耗水量均表现为生育前期少,中期缓慢增加,到灌浆期迅速增加的趋势。全生育期耗水量和耗水强度均随土壤湿度的升高而增大,土壤湿度是影响耗水量、耗水强度及水分利用效率的主要因素,而施氮量的影响作用较弱。     

Detection of Mycoplasmalike Organism of Paulownia Witches′-Broom with DAPI Fluorescence Microscopy

Paulownia witches’-broom infected by mycoplasmalike organism (MLO) has been developed several cytochemical methods for diagnosis. These methods all based on the special stain reactions or abnormal fluorescence in groups of infected sieve elements as a diseased symptom,. not really on the direct detection of MLO under light microscope. This paper deals with the demonstration of MLO specific white fluorescence after DAPI staining with GMA sections of diseased young stems. Such fluorescence was absent in sections from health plants. The results were confirmed by the ulrrastrueture of MLO and the structure of sieve elements showing from PAS-TBO stained GMA sections. The described method may not only be used in accurate diagnosis of MLO diseased in different plants, but is also worth in the studies of MLO distribution in plants, MLO dynamics in plant resting stage and MLO transmission to support the theoretical basis for protection.     

A Preliminary Study on the Wood Anatomy of Manglietia aromatica Dandy [

The present paper deals mainly with the wood structures of “Paramanglietia aromatica” Hu & Cheng and Paramichelia (Pierre) Hu of the Magnoliaceae. These wood structures are listed in Table Ⅰ. In comparison of their wood anatomical features with relsted genera[4], we find that (Ⅰ) the wood anatomy of the reduced genus “Para- manglietia” Hu et Cheng is still within the range of Manglietia Dandy and that (2 the wood anatomical features of Paramichelia (Pierre) Hu is very similar to those of Michelia L. and Tsoongiodendron Chun. We also find that the wood anatomy of Manylietia aromatica Dandy [“Parawanglietia aromatica” (Dandy) Hu & Cheng] is less similar to Manglietiastrum Law (see Table 1).     

Identification of hazelnut (Corylus avellana) cultivars by RAPD analysis

The random amplified polymorphic DNA (RAPD) technique offers a useful tool to detect DNA polymorphisms. It can also be used to distinguish different clones and cultivars. We have developed a comprehensive RAPD-based procedure for the routine molecular typing of various plants. Here we report the application of this technique for the correct identification of six hazelnut cultivars (Corylus avellana) widespread in the Campania region (south Italy). The analysed hazelnut cultivars were successfully distinguished by their RAPD fingerprints using the DNA primers U2, U3, U4, U11 and U14. However, in each cultivar we observed very low genetic heterogeneity among the clonal variants. Since this technique is among the simplest and easiest methods used to fingerprint DNA, it could be easily transferred to less sophisticated laboratory infrastructures (e.g. outstations of crop regulatory agencies). Received: 20 December 1997 / Revision received: 6 August 1998 / Accepted: 13 November 1998