玉米根系分泌物对烟草黑胫病菌的抑制活性及其抑菌物质分析

目的明确玉米、辣椒单作和间作种植后根围土壤细菌群落的变化与病害发生的关系,解析土壤微生物在玉米和辣椒多样性种植中控制病害的作用。方法比较玉米/辣椒间作和分别单作后根围土壤微生物对玉米小斑病和辣椒疫病发生的影响,并应用Illumina Miseq高通量测序技术比较不同处理根围细菌群落的差异。结果单作玉米的根围土壤微生物能显著抑制辣椒疫病的发生(P<0.05),辣椒单作、玉米/辣椒间作后玉米根围土壤微生物降低玉米小斑病的趋势明显。根围土壤细菌群落分析结果表明：单作玉米根围气单胞菌属、堆囊菌属和固氮螺菌属等的相对丰度显著高于间作玉米和单作辣椒根围(P<0.05);单作辣椒和间作玉米根围土壤中拟杆菌门相对丰度上调,并且其中的拟杆菌属、农研丝杆菌属、鞘氨醇杆菌属和Muribaculum的相对丰度也显著上调(P<0.05)。结论玉米/辣椒间作和间作后有利于帮助彼此降低病害的发生。单作或间作后导致土壤细菌群落的变化是其缓解病害发生的重要机制。     

日本落叶松种子园结实母株种实性状对氮磷钾配比施肥的响应

为提高日本落叶松种子园肥料利用率,有效改善种实性状,提高种子产量和品质;在甘肃省沙坝落叶松/云杉国家良种基地,以30年左右正常开花结实的日本落叶松嫁接无性系分株为研究对象,采用随机试验设计,设置了N₁P₁K₁、N₁P₂K₁、N₁P₁K₂施肥配比水平,以不施肥（N₀P₀K₀）作为对照,研究N、P、K不同配比水平施肥对种实性状的影响。数据采用SPSS 16.0进行方差分析和多重比较,结果表明：N、P、K不同配比水平施肥对日本落叶松结实母株种实性状的影响具有显著差异（P<0.05）,不同配比施肥均能促进球果和种子性状的有效改善,N₁P₂K₁、N₁P₁K₁、N₁P₁K₂配比水平施肥千粒质量分别比对照提高了38.1%、32.1%和30.0%;尤其以N₁P₂K₁的效果最为显著,球果鲜质量和单个球果平均生产种子质量是对照（N₀P₀K₀）的2.08倍和2.26倍,也是N₁P₁K₂施肥配比水平的1.53倍,高出N₁P₁K₁施肥配比水平的9.4%和30.0%。30年左右日本落叶松种子园能有效改善种实性状,提高种子产量和品质的N、P、K施肥配比水平为N₁P₂K₁。     

ASR蛋白与植物的抗逆性研究进展

 ASR蛋白（the abscisic acid,stress,ripening protein）是生物体中广泛存在的一类与渗透调节有关的家族蛋白,植物受到逆境胁迫（如干旱、低温、盐胁迫、ABA等）后,ASR蛋白大量表达,可以减轻逆境引起的伤害。ASR蛋白在细胞中可以稳定细胞膜结构,作为分子伴侣,具有结合离子和防止氧化等作用,被认为是在胁迫过程中对植物起保护作用的物质之一。针对这些重要特性,综述了ASR蛋白分类、结构和编码基因及其表达调控方式及ASR基因表达、ASR蛋白积累与植物抗逆性的关系等方面的研究进展。     

作物抗旱性生理生化机制的研究现状和进展

根据现有文献资料，从渗透调节、细胞膜的结构和功能、自由基学说、干旱胁迫下特异蛋白的产生及其生理功能等方面综述了作物抗旱性生理生化机制的研究现状和进展。     

水稻矮缩病毒基因组及毒粒三维结构的研究进展

水稻矮缩病毒(Rice dwarf virus,RDV)为双层壳、二十面体的双链RNA病毒,是水稻的重要病原物之一.文中比较了RDV中国福建分离物与日本分离物基因组各片段核苷酸序列的相似性,发现RDV两个不同分离物基因组相应片段的相似性均在92%以上,最高可达96%;分析了相应基因组片段编码的结构蛋白P1、P2、P3、P5、P7、P8及以前一直被认为是非结构蛋白的P9和非结构蛋白Pns4、Pns6、Pns10 、Pns11和Pns12在RDV复制、组装过程中的功能;回顾了RDV粒子三维结构的研究概况,对RDV粒子内、外层衣壳的晶体学结构作了较详细的描述;简要介绍了RDV复制与组装的机制,发现核心蛋白与dsRNA间相互作用成为一个单元是病毒RNA的分拣及包装到病毒粒子核心内的可能机制.同时,指出基于PDR的植物抗病毒基因工程在水稻矮缩病毒防治上的可能性.     

甜菜优质高产综合配套栽培技术

131团甜菜种植首先走上了产业化发展的道路,积极推广运用新的科学技术,全面启动精准农业工程,强化田管各项技术措施,尤其是将良种良法、精量露播、化学除草、节水灌溉、机械采收、科学施肥及病虫害综合防治等先进适用技术配套应用,甜菜产量、含糖率得到稳步提高。     

美洲黑杨基因资源收存及其遗传评价的研究

从１７个国家引进３３１个黑杨派无性系（其中５２个美洲黑杨无性系）,在山东省长清县营建我国第一个黑杨派无性系基因库。连续１０年对基因库内美洲黑杨无性系进行了多性状系统研究,结果表明各无性系间在物候期、生长、生根、抗寒和抗病虫等方面均存在着显著的差异,遗传变异丰富;系间的主要性状与无性系起源纬度及各性状间存在一定相关性。主要材料性状变异的研究结果表明,３８个８年生美洲黑杨无性系在木材基本密度、纤维长度无性系间变异达到极显著水平;木材密度和纤维长度与树高和胸径呈一定相关性;木材密度和纤维长度这两个性状在遗传上相互独立,受不同遗传机制控制。利用分子遗传标记ＲＡＰＤ技术研究库内美洲黑杨无性系ＤＮＡ多态性,结果表明本库美洲黑杨ＤＮＡ多态率为８６％,再次证明本库美洲黑杨遗传多样性高,可为我国杨树改良提供丰富的育种材料。     

Evaluation of cultivation methods and sustainable agricultural practices for improving shallot bulb production – a review

Abstract

Shallot is an economically important nutritive bulb vegetable and medicinal plant from Alliaceae family. Distributed in limited regions worldwide, in most cases, shallots widely grow in very cold to moderate cold temperate climates at high elevations required to induce bolting and overcome their bulbs and true seeds dormant period. Shallot responses to agricultural management and environmental conditions vary among different species and genotypes and, thus, selection of the elite genotypes is a prerequisite for obtaining desired yield and quality of bulbs and true seeds. Plant material (seed or bulb), plant selection, as well as cultivation and agricultural practices (importantly fertilization, spacing, planting date, and irrigation in greenhouse or farmland) critically affect productivity, phytonutrient value, and economic profit of the shallot produces. The knowledge of using biofertilizers and mulching techniques on shallots are currently evolving, but the information on the efficiency of nanobiofertilizers and eco-friendly and biodegradable mulching materials on shallots farming are still lacking. With the emphasis on sustainable agricultural systems, the efficiency of combined organic and inorganic fertilization is discussed and the potential biofertilizer agents are recommended. This review highlights the importance of using the integrated fertilization (organic and inorganic methods combined with biofertilizers) and irrigation methods (such as two-line spray hose irrigation combined with mulching), and the practices with the highest potential to further improve shallot farming are suggested. The information on shallots breeding is still lacking and requires extensive researches in the future.     

An evaluation of the potential influence of SST and currents on the oceanic migration of juvenile and immature chum salmon (Oncorhynchus keta) by a simulation model

Using a salmon migration model based on the assumption that swimming orientation is temperature dependent, we investigated the determining factors of the migration of juvenile and immature chum salmon (Oncorhynchus keta) in the North Pacific. We compared the predictions of the model with catch data of immature and juvenile chum salmon collected by Japanese research vessels from 1972 to 1999. The salmon migration model reproduced the observed distributions of immature chum salmon and indicates that passive transport by wind‐driven and geostrophic currents plays an important role in the eastward migration of Asian salmon. These factors result in a non‐symmetric distribution of Asian and North American chum salmon in the open ocean. The directional swimming component contributes to the northward migration in summer. The model results indicate that during the first winter Asian chum salmon swim northward against the southward wind‐driven currents to stay in the western North Pacific. This suggests that Asian chum salmon require more energy to migrate than other stocks during the first winter of their ocean life.     

巨大芽胞杆菌E-1菌株对土壤氯嘧磺隆残留的降解效果

采用玉米对氯嘧磺隆敏感的原理,测定巨大芽胞杆菌E-1对土壤氯嘧磺隆残留的降解能力。结果表明降解菌用量为300 mL菌液/kg土时,对玉米根长的修复率为18.31%～62.48%;降解菌用量30 mL菌液/kg土时的修复率为11.78%～49.72%;降解菌用量3 mL菌液/kg土时,施用降解菌的处理与不施菌处理之间无显著差异。