山西产9种野生植物的染色体观察

本文报道了产于山西的4科5属9种野生植物的染色体观察结果。其中有2种植物作了核型分析,5种植物的染色体为首次报道。     

濒危植物矮牡丹的分布格局及其生存群落的数量分析

对山西稷山马家沟,永注水峪口,陕西延安万花山,华阴二仙桥４个地区矮牡丹生存群落进行了分类和排序研究,ＴＷＩＮＳＰＡＮ分类将矮牡丹生存群落分为１０类,分类结果在ＤＣＡ二维排序图上得以了有效的验证,说明矮牡丹适应能力较强,但除了在地带性顶级群落辽宁栎林下矮牡丹能形成灌木层优势种外,在其它群落中,矮牡丹只属于群落的伴生成分,用Ｍｏｒｉｓｔａ指数法,负二项指数法和方差均值比３种方法对矮牡丹种群进行了分布格     

有序样方聚类在植被垂直划分中的应用

 本文介绍一种非等级分类方法——有序样方聚类法,并将其应用于山西绵山植被垂直带的划分,结果为：1,落叶阔叶林带(包含3个亚带：Ⅰ．落叶阔叶灌丛亚带,Ⅱ．松栎林亚带,Ⅲ．落叶阔叶林亚带),2．寒温性针叶林带和3,亚高山草甸带。基于黄金分割法(或Fisher’s法)的有序样方聚类法,是按照样方在空间(或时间)先后出现的序号和组内相似性最大,组间相似性最小的标准,对样方进行分类,因此,所得结果是最优的。与TWINSPAN的结果比较,在绵山植被遭到严重扰动的情况下,有序样方聚类要优于TWINSPAN。     

Comparative metabolomics of the interaction between rice and the brown planthopper

Introduction

The interactions between plants and insect herbivores are complex and multifaceted. Rice and its specialist insect pest the brown planthopper (BPH), Nilaparvata lugens Stål (Hemiptera: Delphacidae) constitute an ideal system for studying plant–insect interactions.

Objectives

Combined metabolomics analyses of rice plant and BPH were conducted to understand the mechanism of host rice plant defense and BPH insect response.

Methods

Metabolite dynamics in rice leaf sheath and BPH honeydew was investigated using the gas chromatography–mass spectrometry (GC–MS) method. The GC–MS data were analyzed by principal component analysis and partial least squares-discriminant analysis.

Results

Twenty-six metabolites were detected in the leaf sheath extracts. Rice leaf sheath metabolomics analysis results show that BPH feeding induces distinct changes in the metabolite profiles of YHY15 and TN1 plants. These results suggest that BPH infestation enhance fatty acid oxidation, the glyoxylate cycle, gluconeogenesis and the GABA shunt in TN1 plants, and glycolysis and the shikimate pathway in YHY15. We propose that the BPH15 gene mediates a resistance reaction that increases the synthesis of secondary metabolites through the shikimate pathway. Thirty-three metabolites were identified in BPH honeydew. Honeydew metabolomics analysis results show that when BPH insects were fed on resistant YHY15 plants, most of the amino acids in honeydew were significantly decreased compared to those of BPH fed on TN1 plants. Based on metabolomics results, we propose that BPH feeding on resistant YHY15 plants would enhance amino acid absorption. At the same time, urea was significantly increased in BPH fed on YHY15.

Conclusion

Metabolomics study is valuable in understanding the complex and multifaceted interaction between plants and insect herbivores and provide essential clue for development of novel control BPH strategies.

     

Functional Analysis of <Emphasis Type="Italic">VvBG1</Emphasis> During Fruit Development and Ripening of Grape

β-glucosidase (BG) was believed to take part in abscisic acid (ABA) synthesis via hydrolysis of ABA glucose ester to release active ABA during plant growth and development. However, there is no genetic evidence available to indicate the role of genes during fruit ripening. Here, the expression patterns of three genes (VvBG1, VvBG2, and VvBG3) encoding β-glucosidase were analyzed during grape fruit development, and it was found that β-glucosidase activity increased in grape fruit in response to various stresses. Furthermore, to verify the function of β-glucosidase during fruit ripening, heterogeneous expression of the VvBG1 gene in strawberry fruit was validated, and the results showed that the VvBG1 over-expression increased β-glucosidase and promoted the fruit ripening process in strawberry. In addition, we found that ABA contents increased in the VvBG1 over-expression of strawberry fruit, which induced fruit anthocyanin, soluble solid accumulation, and fruit softening. Moreover, genes related to coloring (CHS, CHI, F3H, and UFGT), softening (PG1, PL1, and EXP1), and aroma (SAAT, and QR) were up-regulated. This work will elucidate the specific roles of VvBGs in the synthesis of ABA and provide some new insights into the ABA-controlled grape ripening mechanism.     

Conservation of microRNA-mediated regulatory networks in response to copper stress in grapevine

Jatropha curcas L. as a bio energy plant belonging to the Euphorbiaceae family is gaining progressive importance over the last years. In 2012 and 2014 field experiments were carried out to assess the effects of cytokinins 6-Benzyladenine (BA) and Forchlorfenuron (CPPU) acting as plant growth regulators (PGRs). Number of flowers per inflorescence, female-to-male ratio of flowers, fruits per infructescence, fruiting rate, number of seeds per fruit, seed size and weight as well as seed oil content were determined. It was suggested that concerning effectiveness of exogenous application of PGRs the developmental stage of flower is very important. Due to that, special interest was laid on the age of inflorescences at the time of application. Our experiments revealed a strong dependence of cytokinin effectiveness on the developmental stage of flowering. So treatment of plants with 6-Benzyladenine at the beginning of flower formation (stage 1) significantly increased the number of male and female flowers per inflorescence, whereas treatment at an advanced flowering stage (stage 2) or at the stage of fully developed flowers (stage 3) had only slight or no effects. In contrast, fruit retention was progressively increased by treatment in stage 2 and 3. Application of Forchlorfenuron significantly increased female-to-male ratio in stage 1 flowers but showed no effects on stage 2 and 3. 6-Benzyladenine as well as Forchlorfenuron showed equal effects on number of fruit inflorescences treated in stage 1. Our results show a significant decrease in seed weight due to BA- and CPPU-application while kernel weight remained stable. Concerning fruits, clusters and oil yield per tree, BA-application showed significant increasing effects. This study indicates that 6-Benzyladenine and Forchlorfenuron can improve yield affecting parameters in J. curcas when the phenological stage of flowering at time of application is precisely considered.     

冬小麦对有限水分高效利用的生理机制

通过对不同土壤供水条件下的孕穗开花期的冬小麦叶片CO₂/H₂O气体交换参数的系统测定,研究了光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、细胞间隙CO₂浓度(Ci)、叶温(Tl)与水分利用效率(WUE)间的关系。结果表明,WUE并不随Pn的增长直线增长,而是呈现出二次曲线的变化趋势;只有当蒸腾达到一定程度时,Tr才对WUE产生影响,而Tr过大时WUE则有下降的趋势;WUE与Ci呈负相关,随Ci的增加WUE呈递减趋势;叶温升高对光合和蒸腾都有促进作用,当超过了某种限度则表现为抑制作用,表明在一定温度范围内,Tl升高对水分利用不利;随Gs的增大,WUE增大到一定程度则不再增加,甚至出现一种回落趋势.