油菜素内酯（BR）促进植物生长机理研究进展

介绍了油菜素内酯促进植物生长,提高作物产量的作用,并简述了促进生长的生理代谢基础,通过比较油菜素内酯与生长素,赤霉素促进生长作用方式的异同,提出油菜素内酯促进生长的信号传导路径不同于其它植物激素,另外从细胞的形态发生,细胞壁扩展的机制和细胞骨架在细胞伸长中的作用等几个方面对油菜素内酯促进植物生长的细胞及分子生物学机制进行了详尽的论述。     

拟南芥油菜素内酯信号转导研究进展

油菜素内酯（brassinosteroid）信号首先被膜上的受体BRI1／BAK1复合体感知,然后在一系列蛋白参与下传递到核内,进一步调控下游基因的表达。本文综述了拟南芥中油菜素内酯信号转导研究的进展,并对今后的研究方向进行了探讨。     

拟南芥油菜素内酯信号转导研究进展

油菜素内酯(brassinosteroid)信号首先被膜上的受体BRI1/BAK1复合体感知, 然后在一系列蛋白参与下传递到核内, 进一步调控下游基因的表达。本文综述了拟南芥中油菜素内酯信号转导研究的进展,并对今后的研究方向进行了探讨。     

油菜素内酯对水稻幼苗硝酸还原酶活性的影响（简报）

油菜素内酯(BR)明显提高水稻幼苗的硝酸还原酶(NR)活性,并促进NO_3~-的吸收。环己亚胺(CHI)和脱落酸(ABA)都抑制 NR活性,而这些抑制不为 BR所逆转。BR和苄基腺嘌呤(BA)单独处理都促进NR活性,但两者不表现加成作用。     

表油菜素内酯对西瓜生长和产量性状的影响（简报）

表油菜素内酯明显促进三叶期西瓜幼苗生长,提高其叶绿素含量和光合作用速率,开花期喷雾处理能增强座果和提高产量20％左右,并可延缓叶片衰老。     

油菜素内酯生物合成与功能的研究进展

植物激素油菜素内酯广泛调节植物的生长发育及对外界环境因子变化的反应,在作物上的应用也已引起人们的广泛兴趣。通过遗传学等手段对相关突变体及功能基因的研究为其生物合成与功能研究提供了基础。本文总结了油菜素内酯在植物各组织内的分布、生物合成、相关合成突变体及其编码基因的性质、生理功能以及与其它激素间的相互作用等。     

油菜素内酯生物合成与功能的研究进展

植物激素油菜素内酯广泛调节植物的生长发育及对外界环境因子变化的反应, 在作物上的应用也已引起人们的广泛兴趣。通过遗传学等手段对相关突变体及功能基因的研究为其生物合成与功能研究提供了基础。本文总结了油菜素内酯在植物各组织内的分布、生物合成、相关合成突变体及其编码基因的性质、生理功能以及与其它激素间的相互作用等。     

表油菜素内酯对玉米果穗发育的影响（简报）

在玉米雌穗小穗和小花分化期,全株喷施0.01 ppm表油莱素内酯(BR)能促进幼穗发育,使幼穗的生长速度加快、吐丝提前,籽粒的败育率减少,从而导致玉米产量的提高。     

植物细胞壁松弛因子

植物细胞壁的松弛是细胞伸长必需的一个生理过程,发生于植物生长发育的各个阶段。研究发现参与细胞壁松弛的因子有多种,主要包括膨胀素（expansin）、木葡聚糖内转糖苷酶/水解酶（XTH）、糖基水解酶和羟基自由基（·OH）四大类。本文主要对这些细胞壁松弛因子的结构特征、作用机制及其在植物生理过程中的作用等方面的研究进展进行综述。     

植物幼苗玻璃化发生机制研究进展

玻璃化是指植物生长过程中出现的类似水浸状的半透明化生理病变现象,常见于植物组织培养。玻璃化现象是限制组培技术发展和组培苗商业化生产的三大主要影响因素之一,但是玻璃化的发生机制至今尚不清楚。以组培材料为对象研究玻璃化机制受多种人为因素的干扰,而以非组织培养材料为研究对象,避免了人为因素的干扰,有助于从本质上揭示玻璃化发生的分子机制。该文综述了非组培苗因软木脂含量改变、表皮蜡质合成减少、细胞膜过氧化受损、离子或水分子跨膜运输受阻等导致植物玻璃化的机制,以期为最终揭示植物玻璃化机制提供参考。     

Studies on Plant Growth Substances

The plant growth activities of the dihydro- and tetrahydro-1-naphthoic acids substituted with a halogen, methyl or nitro group at various positions of the aromatic ring are measured by the pea straight-growth test. The relationship between structure and activity is discussed. The results seem to conform well with the spatial structure hypothesis of Veldstra.     

Studies on Plant Growth Regulators

The electronic structure of atropic acid and its β-alkyl and β,β-dimethyl derivatives is calculated by a molecular orbital method. Their plant growth activity is shown to be explained only by considering an electronic factor of the molecule derived by the calculation.     

Studies on Plant Growth Regulators

The auxin activities of the homologs of racemic and enantiomeric α-alkylphenylacetic acids were estimated by pea straight growth test. The α-methyl, -ethyl and -propyl acids were moderately active whereas the longer and branched alkyl chain were found to make the molecule inactive. The more active enantiomers were shown to have the same configuration as the more active enantiomers in the other series of the optical active synthetic auxins.

The auxin activities of the cyclic homologs of 1, 2, 3, 4-tetrahydro- and 3, 4-dihydro-1- naphthoic acids were determined by pea straight growth test. In the tetrahydro-acid series, it was observed that the alicyclic ring expansion from the 6-membered to the 7-membered made the molecule inactive. In the 3, 4-dihydro-acid series, on the other hand, the activity remained almost unchanged by such a structural change. Structure-activity relationships were discussed in terms of their molecular structures, in particular, the configuration of the carboxyl group.     

Studies on Plant Growth Substances

1-Naphthoic acid derivatives substituted with chlorine, bromine, methyl or nitro groups at various positions of the ring were assayed for their activities in the pea straight-growth and the callus formation tests. Their growth activities are discussed from two points of view, i.e. the spatial structure hypothesis of Veldstra and the ortho reaction hypothesis advanced for benzoic acid derivatives proposed by Hansch and Muir. It appears that a combination of these two views are appropriate for the present authors’ results.     

DELLA家族蛋白与植物生长发育的关系

赤霉酸(GA)同细胞膜上的受体结合后,通过一系列信号分子,把信号传递到下游,以调节植物的生长发育.在已发现的植物GA信号传递分子中,有一类的N端具有高度保守的DELLA结构域,称之为DELLA家族蛋白.文中介绍了此类蛋白作为阻遏蛋白,对植物生长发育的调控作用及其行使阻遏作用的分子机制.     

Preferential Promotion of Lycopersicon esculentum (Tomato) Growth by Plant Growth Promoting Bacteria Associated with Tomato

A total of 74 morphologically distinct bacterial colonies were selected during isolation of bacteria from different parts of tomato plant (rhizoplane, phylloplane and rhizosphere) as well as nearby bulk soil. The isolates were screened for plant growth promoting (PGP) traits such as production of indole acetic acid, siderophore, chitinase and hydrogen cyanide as well as phosphate solubilization. Seven isolates viz., NR4, NR6, RP3, PP1, RS4, RP6 and NR1 that exhibited multiple PGP traits were identified, based on morphological, biochemical and 16S rRNA gene sequence analysis, as species that belonged to four genera Aeromonas, Pseudomonas,Bacillus and Enterobacter. All the seven isolates were positive for 1-aminocyclopropane-1-carboxylate deaminase. Isolate NR6 was antagonistic to Fusarium solani and Fusarium moniliforme, and both PP1 and RP6 isolates were antagonistic to F. moniliforme. Except RP6, all isolates adhered significantly to glass surface suggestive of biofilm formation. Seed bacterization of tomato, groundnut, sorghum and chickpea with the seven bacterial isolates resulted in varied growth response in laboratory assay on half strength Murashige and Skoog medium. Most of the tomato isolates positively influenced tomato growth. The growth response was either neutral or negative with groundnut, sorghum and chickpea. Overall, the results suggested that bacteria with PGP traits do not positively influence the growth of all plants, and certain PGP bacteria may exhibit host-specificity. Among the isolates that positively influenced growth of tomato (NR1, RP3, PP1, RS4 and RP6) only RS4 was isolated from tomato rhizosphere. Therefore, the best PGP bacteria can also be isolated from zones other than rhizosphere or rhizoplane of a plant.

Electronic supplementary material

The online version of this article (doi:10.1007/s12088-014-0470-z) contains supplementary material, which is available to authorized users.     

Studies on Plant Growth Accelerating Substances

By the aid of Chlorella grown on an agar plate a new method has been devised to detect soil microbes which produce plant growth accelerating substances. From the results of examining 3,300 soil microbes by this method, it was shown that the soil microbes could be divided into three groups according to their effect on the growth of Chlorella, that is, Chlorella growth accelerators, inhibitors and non-accelerators. By the cultivation of some green plants in the existence of some of these microbes or their culture filtrates, it was further shown that their effect on the growth of Chlorella and that of plants were in parallelism as a rule. The growth accelerating substances that are produced by soil microbes found in the present research were shown by the comparative experiment to be quite different from the substances previously known.     

Plant Growth Promoting Metabolites of Sclerotinia sclerotiorum

In the research on the plant growth regulators produced by phytopathogenic fungi, two active metabolites, sclerotinin A and B, in addition to sclerin have been isolated from the culture filtrate of S. sclerotiorum. Sclerotinin A and B have been shown to be 3,6,8-tri-hydroxy-3,4,5,7-tetramethyl-3,4-dihydroisocoumarin and 3,6,8-trihydroxy-3,5,7-trimethyl-3,4- dihydroisocoumarin, respectively.