A novel protein accumulated during maturation of the pods of the plantImpatiens balsamina

A high molecular weight protein has been isolated as a major polypeptide comprising 85% of the total extractable proteins in the fruit pericarp of the plantImpatiens balsamina. The protein has been purified to homogeneity following fractionation of the crude cell supernatant with ammonium sulphate, chromatography on Sepharose 4B and Sephacryl-S-300. This protein appeared to be a homo-tetramer consisting of subunits, Mr 75 K. Amino acid analysis showed the presence of more acidic amino acids, with an isoelectric point 5.8. The interaction of this protein with filamentous actin, both from rabbit muscle and Mung bean embryo was monitored by transmission electron microscopy, light scattering analysis, viscometry and sedimentation assay. This protein inhibited appreciably the polymerization of G-actin to F-actin.     

A systematic histological study of palm fruits. III. Subtribe Iguanurinae (Arecaceae)

This study represents a preliminary sampling of the pericarp histology of the subtribe Iguanurinae (tribe Areceae, subfamily Arecoideae) of the family Arecaceae. At least one sample from each of the 27 recognized genera was examined and illustrated with a line drawing. This sampling serves to characterize fruit structure in the subtribe as a whole, to illustrate the diversity of pericarp adaptations found in the subtribe, to characterize the monotypic genera, to provide hypotheses about the characterization of the larger genera, and to test existing phylogenetic hypotheses about the Iguanurinae. There are no unique tissues present in the pericarp in this subtribe, but genera can be readily characterized by unique combinations and distributional patterns in common tissues. These patterns, and some prominent evolutionary trends, parallel those in related subtribes of Areceae, such as the Ptychospermatinae and Arecinae. Significant in this subtribe is variation in the distribution of tanniniferous cells, raphide-bearing cells and brachysclereids, in the sculpturing of the seed and the locular epidermis, in the thickness of the locular epidermis, in the thickness of the fibrous vascular bundle sheaths, and especially in the number, orientation and distribution of nonvascular fibrous bundles. One major trend is the formation of systems of separate fibrous bundles and their progressive displacement toward the outer layer of the fruit, where a complex exocarp may form. The diversity of pericarp structure in the Iguanurinae is far greater than in the two subtribes previously studied.     

紫娘喜荔枝果皮K、Ca和Mg含量变化对着色的影响

为探讨紫娘喜荔枝(Litchi chinensis)着色与果皮K、Ca和Mg含量变化的关系,以紫娘喜荔枝果皮为试材,通过对数据作典型性相关和一元指数函数回归分析,研究其K、Ca、Mg含量变化及其对叶绿素、花色素苷等含量的影响特点。结果表明:随着果皮不断转红,叶绿素含量呈显著下降趋势,而花色素苷含量却呈显著上升趋势;全K、水溶性K和全Ca、水溶性Ca含量分别呈下降和上升的趋势,水溶性Mg含量呈上升趋势,全Mg含量变化不显著,同期全K、Ca、Mg和水溶性K、Mg、Ca等含量分别呈依次递减趋势;花色素苷含量与全Ca和全K含量分别呈正和负相关的一元指数函数回归关系;叶绿素含量与水溶性Mg、全Ca和全K含量分别呈负、负和正相关一元指数函数回归关系。可见,全Ca含量较高是促进果皮转红的关键因素,研究结果可为制定紫娘喜荔枝合理施肥技术提供理论依据。     

香樟果皮花色苷提取工艺优化及抗氧化研究

为了优化香樟果皮花色苷的最佳提取工艺条件,用乙醇作为提取溶剂,选取提取时间、提取温度、提取剂浓度、料液比、pH五因素,采用Box-Behnken建立三因素三水平模型,用响应面法优化各因素及其相互作用的最佳组合,用Design-Expert 8.0设计回归正交实验;同时用水杨酸比色法和DPPH法,测定了香樟果皮花色苷的抗氧化能力,并比较了不同放置时间对香樟果花色苷稳定性的影响。结果表明:香樟果花色苷最佳提取工艺的回归方程为Y=58.64+2.27A+12.78B+10.18C-14.01A2-11.00B2-7.56C2,R2=0.9796,模型拟合程度良好,在该试验范围内,模型能够准确反映花色苷的提取结果;最佳工艺参数分别为pH1.0、料液比1∶15、乙醇浓度78.59%、提取温度77.14℃、提取时间42.48min,在此条件下香樟果花色苷的得率为67.99mg·100g-1;在一定浓度范围内,香樟果皮花色苷清除羟自由基率和总抗氧化能力均与浓度成正线性相关,回归方程分别为y=0.3388x+13.485(R2=0.9856),y=0.0275x+0.0221,(R2=0.9966)。利用响应面法确定的最佳工艺条件合理,可用于香樟果皮花色苷的提取,同时香樟果花色苷具有良好的抗氧化活性,为天然色素的开发利用提供一定指导意义。     

Pericarp development and fruit structure in borassoid palms (Arecaceae-Coryphoideae-Borasseae)

Background and Aims

The Borasseae form a highly supported monophyletic clade in the Arecaceae–Coryphoideae. The fruits of Coryphoideae are small, drupaceous with specialized anatomical structure of the pericarp and berries. The large fruits of borassoid palms contain massive pyrenes, which develop from the middle zone of the mesocarp. The pericarp structure and mode of its development in Borasseae are similar to those of Eugeissona and Nypa. A developmental carpological study of borassoid palms will allow us to describe the process of pericarp development and reveal the diagnostic fruit features of borassoid palms, determine the morphogenetic fruit type in Borasseae genera, and describe similarities in fruit structure and pericarp development with other groups of palms.

Methods

The pericarp anatomy was studied during development with light microscopy based on the anatomical sections of fruits of all eight Borasseae genera.

Key Results

The following general features of pericarp structure in Borasseae were revealed: (1) differentiation of the pericarp starts at early developmental stages; (2) the exocarp is represented by a specialized epidermis; (3) the mesocarp is extremely multilayered and is differentiated into several topographical zones – a peripheral parenchymatous zone(s) with scattered sclerenchymatous elements and vascular bundles, a middle zone (the stony pyrene comprising networks of elongated sclereids and vascular bundles) and an inner parenchymatous zone(s); (4) differentiation and growth of the pyrene tissue starts at early developmental stages and ends long before maturation of the seed; (5) the inner parenchymatous zone(s) of the mesocarp is dramatically compressed by the mature seed; (6) the endocarp (unspecialized epidermis) is not involved in pyrene formation; and (7) the spermoderm is multilayered in Hyphaeninae and obliterated in Lataniinae.

Conclusions

The fruits of Borasseae are pyrenaria of Latania-type. This type of pericarp differentiation is also found only in Eugeissona and Nypa. The fruits of other Coryphoideae dramatically differ from Borasseae by the pericarp anatomical structure and the mode of its development.     

PSA: software for parental structure analysis of seed or seedling patches

Parental structure analysis (PSA) is a computer program to analyse separate contributions of paternal and maternal parents to postdispersal plant offspring. The program provides joint estimates of maternal, paternal and cross‐parental correlations within and among a set of predefined groups of seeds or seedlings, as well as derivative estimates of effective parental numbers. PSA utilizes data sets that distinguish between maternal and paternal contributions to the genotype of each offspring in the sample, but does not require parental samples per se. The approach requires assay of codominant diploid markers from both seed coat (maternally inherited) and seedling/embryo (biparentally inherited) tissues for each offspring. A simulation analysis of PSA's performance shows that it provides fairly accurate parental correlation estimates from affordable sampling effort. PSA should be of interest to plant biologists studying the interplay between dispersal, demography and genetics, as well as plant–animal interactions.     

Tissue dependent variations of DNA methylation and endoreduplication levels during tomato fruit development and ripening

Tomato fruit cells are characterized by a strong increase in nuclear ploidy during fruit development. Average ploidy levels increased to similar levels (above 50C) in two distinct fruit tissues, pericarp and locular tissue. However, ploidy profiles differed significantly between these two tissues suggesting a tissue-specific control of endoreduplication in tomato fruit. To determine possible relationships between endoreduplication and epigenetic mechanisms, the methylation status of genomic DNA from pericarp and locular tissue of tomato fruit was analysed. Pericarp genomic DNA was characterized by an increase of CG and/or CNG methylation at the 5S and 18S rDNA loci and at gyspsy-like retrotransposon sequences during fruit growth. A sharp decrease of the global DNA methylation level together with a reduction of methylation at the rDNA loci was also observed in pericarp during fruit ripening. Inversely, no major variation of DNA methylation either global or locus-specific, was observed in locular tissue. Thus, tissue-specific variations of DNA methylation are unlikely to be triggered by the induction of endoreduplication in fruit tissues, but may reflect tissue-specific ploidy profiles. Expression analysis of eight putative tomato DNA methyltransferases encoding genes showed that one chromomethylase (CMT) and two rearranged methyltransferases (DRMs) are preferentially expressed in the pericarp during fruit growth and could be involved in the locus-specific increase of methylation observed at this developmental phase in the pericarp.     

大核和焦核"桂味"荔枝果实发育及其发育期间果皮中内源激素含量的变化比较

同一株大核和焦核"桂味"荔枝的果实生长型均呈"单S型",其果实大小差异主要由种子大小不同引起.果实发育期间,两者果皮中内源激素变化的规律大体上一致,大核果皮中GA3、IAA含量和(IAA ZRs GA3)/ABA比值均高于焦核果皮,但ZRs含量和ZRs/ABA比值则比其低,ABA含量的差异无规律可循.     

Ontogeny and structure of the drupe of Ozoroa paniculosa (Anacardiaceae)

An exocarp sensu stricto develops from the outer epidermis of the ovary wall. At maturity it comprises extensively radially elongated palisade-like parenchyma cellS. Besides having an outer cuticle, the outer tangential and outer parts of the radial cell walls of these cells are strongly cutinized. Large, permanently open stomata and saucer-shaped depressions also characterize the exocarp. The mature mesocarp sensu stricto consists of secondarily thickened parenchyma and brachysclereidS. An abundance of tanniniferous deposits and crystals, as well as secretory ducts associated with the vascular bundles also form part of the mature mesocarp. Derivatives of the inner epidermis of the ovary wall differentiate into the stratified endocarp sensu stricto. At maturity this comprises consecutive layers of macrosclereids, osteosclereids (typified by a capitate part and cell wall flutes), brachysclereids, and crystalliferous sclereidS. Pericarp structure is related to its taxonomic significance and the possible role of micromorphological characters in the survival strategy of Ozoroa paniculosa. It is shown that ontogenetic studies contribute to the precise interpretation of previously described cell layers, ensuring that homologous tissues are compared in different taxa.