稻田福寿螺的发生规律及综合防治

本文描述了福寿螺的形态特征,总结其为害特点和发生规律,并提出了防治措施,以减少稻田福寿螺对水稻危害造成的损失。     

石门县福寿螺分布和危害现状及防治对策

实地调查了解石门县福寿螺的分布和危害情况,石门县福寿螺主要发生在夹山镇、蒙泉镇、皂市镇3个乡镇的24个村,集中在道水流域和皂市镇的白沙渡村。全县福寿螺危及农田面积已达1722.7 hm^2,水稻成灾面积约233 hm^2。引进检疫把关不严、福寿螺的适应性广、抗性强和繁殖能力强是造成石门县福寿螺危害的主因。提出了对福寿螺危害的防控策略。     

稻田福寿螺的发生、危害及其防控技术研究进展

水稻是我国乃至全世界重要的粮食作物之一,全球一半以上的人口以稻米为主要食物来源。福寿螺作为一种外来入侵生物对水稻构成的巨大威胁已经受到了国内的广泛关注。水稻从播种至搁田前都会受福寿螺啮食,播种时啮食稻种的芽胚,苗期啮食幼苗整株,导致水稻缺苗和有效分蘖减少,特别是在直播稻种植面积不断增加的情况下,水稻产量受到严重影响。本文综述了福寿螺的种类、生物学特性、稻田为害规律、田间防控技术及资源化利用等,并在此基础上对福寿螺防控及其可持续利用进行展望,旨在为进一步防控稻田福寿螺,保障水稻的产量与质量,降低农户经济损失提供依据。     

稻田福寿螺化学防治试验

稻田福寿螺化学防治试验（宁德地区农科所，福安３５５００３）李惠明，林起（福安市甘棠农技站）苏铬义福寿螺（ＡｍｐｕｌｌａｒｉｕｍｃｒｏｓｅａｎａＨｉｄａｌｇｏ）属两栖淡水贝类软体生物，食性杂，适生性强，繁殖速度快。近年来，我区沿海稻田福寿螺为害的损失逐...     

衡山县外来入侵生物危害现状与防控对策

衡山县已发现空心莲子草、福寿螺等8种外来入侵生物。在分析衡山县外来入侵生物发生、危害及防控现状的基础上,提出强化宣传与监督执法、开展封锁与定点铲除、加强防控技术研究与推广、变害为益、综合利用等防控对策与建议。     

密达6%颗粒剂～高效、环保、安全

ＭＥＴＡ密达颗粒剂是瑞士龙沙公司生产的特效杀螺剂。当蜗牛、蛞蝓、福寿螺等软体动物的足脚接触或进食后，密达即产生触杀和胃毒作用，在短时间内中毒死亡。该药的有效成份为密达６％，通用名称为四聚乙醛，原药白色，制剂为浅蓝色，遇水软化。对鸟类及水生物毒性低，大...     

青岛市花生田蛴螬发生与无公害防治研究

分析了青岛市花生蛴螬发生种类、原因及防治方法,阐述了无公害防治研究进展,包括利用化学物质预报和控制、病原微生物药剂防治以及天敌防治等方法。     

我国亚洲玉米螟的防治现状及展望

综述了我国玉米螟的主要防治方法,着重介绍了物理防治、化学防治、生物防治及研究进展,并讨论了我国玉米螟防治方法中存在的问题及发展方向.     

广东地区茶园小绿叶蝉的综合防治

茶园小绿叶蝉的发生一年有两次高峰期,严重危害茶树生长,影响茶叶产量与品质。目前关于茶园小绿叶蝉的防治方法的研究颇多,本文主要从广东地区小绿叶蝉的发生特点,从生态防治、物理防治、生物防治、化学防治四个方面分析广东地区茶园小绿叶蝉的防治方法,为茶园生态发展与无公害管理提供参考。     

水稻负泥虫生物学特性及其防治

介绍了水稻负泥虫的生活史、生活习性及其危害,提出了采取人工防治、药剂防治的防治方法。     

兜兰离体快繁技术研究进展

由于生境破坏和人工过度采挖及繁殖的障碍,兜兰已是世界上最濒危的植物物种之一,所有野生种均被列入《濒危野生动植物种国际贸易公约》附录I而被禁止交易。突破其种苗繁殖技术瓶颈有利于兜兰种质资源的保护和可持续利用。本文对兜兰属植物无菌播种、共生萌发和组织培养技术等离体快繁技术的进展进行综述,并提出了目前存在的问题和解决方法,以期为兜兰属植物离体繁殖技术的深入研究和优质种苗的规模化生产提供参考。     

High variation in frequency of infection by endophytes in cultivars of meadow fescue in Finland

Systemic and asymptomatic Neotyphodium fungal endophytes infect numerous species of the Poaceae. The frequencies of Neotyphodium endophyte infection in Finland were investigated among and within seven Nordic cultivars of meadow fescue, Schedonorus pratensis (Huds.) P. Beauv., which is a widely grown pasture and forage grass species in Scandinavia. The cultivars were Kasper, Salten, Antti, Fure, Ilmari, Inkeri and Kalevi. Frequencies of infection of cultivars varied from endophyte-free cultivar Fure to highly infected cultivar Inkeri [mean (standard deviation of mean) of 0·95 (0·023)]. Mean frequencies of infection of three cultivars remained lower than 0·10, and two of the cultivars, Kasper and Salten, were intermediately infected. In most of the cultivars, frequencies of infection varied only slightly among seed lots. In cultivar Kasper, however, the frequency of endophyte infection was highly variable (0–0·96) among the 45 seed lots examined. The relative importance of cultivar, seed lot and infection by Neotyphodium endophyte to the aphid Rhopalosiphum padi L. was studied experimentally, using both endophyte-free and endophyte-infected plants of four seed lots of the two intermediately infected cultivars. Endophyte infection increased plant resistance to R. padi , overriding the influences of seed lot and cultivar. It is proposed that variation caused by endophyte infections in cultivars of meadow fescue should be taken into account in assessing plant breeding programmes in Europe.     

Investigation of Polymorphisms in Coding Region of OsHKT1 in Relation to Salinity in Rice

Rice(Oryza sativa) is sensitive to salinity, but the salt tolerance level differs among cultivars, which might result from natural variations in the genes that are responsible for salt tolerance. High-affinity potassium transporter(HKTs) has been proven to be involved in salt tolerance in plants. Therefore, we screened for natural nucleotide polymorphism in the coding sequence of Os HKT1, which encodes the HKT protein in eight Vietnamese rice cultivars differing in salt tolerance level. In total, seven nucleotide substitutions in coding sequence of Os HKT1 were found, including two non-synonymous and five synonymous substitutions. Further analysis revealed that these two non-synonymous nucleotide substitutions(G50T and T1209A) caused changes in amino acids(Gly17Val and Asp403Glu) at signal peptide and the loop of the sixth transmembrane domain, respectively. To assess the potential effect of these substitutions on the protein function, the 3D structure of HKT protein variants was modelled by using PHYRE2 webserver. The results showed that no difference was observed when compared those predicted 3D structure of HKT protein variants with each other. In addition, the codon bias of synonymous substitutions cannot clearly show correlation with salt tolerance level. It might be interesting to further investigate the functional roles of detected non-synonymous substitutions as it might correlate to salt tolerance in rice.     

马铃薯试管苗组织培养及微型薯诱导技术的研究

通过加入不同浓度的BA、NAA和KT,以探讨外源激素对马铃薯试管苗生理性状的影响,发现低浓度的外源激素较适合用来进行试管苗的增殖。本试验利用香豆素进行微型薯的诱导,结果表明低浓度的香豆素对提高薯重和大薯率有利,而高浓度有利于提高微型薯的结薯数量。     

Role of invertase in the accumulation of sugars in cold-stored potatoes

Freshly harvested potatoes contain low levels of total invertase and high levels of invertase inhibitor. Total invertase increases sharply when potatoes are placed in cold storage, but the inhibitor is not depleted in all varieties. The absence of basal invertase activity in Norchip tubers indicates that an excess of invertase is not required for reducing sugar formation. Analyses of 37 varieties and seedlings after 3 months cold storage revealed that the reducing sugar content is not proportional to the invertase activity. High sugar contents are associated with low inhibitor levels, but low sugars are not necessarily associated with high inhibitor levels. The results indicate that invertase participates in reducing sugar formation, but other factors are responsible for the regulation of starch-sugar conversion in potatoes during cold storage.     

Quantitative assessment of metals in local brands of tea in Pakistan

In present study, Mn, Fe, Zn, Cu, Co, Pb, Cr, Ni and Cd were analyzed by FAAS in green and black tea samples of locally available in the Pakistani market. Na and K were also determined by Flame Photometer. Tea leaves can be the source of mineral components and trace elements, as well as some undesirable substances due to exposure to the environment. Among the metals tested, K was the most abundant one followed by Na, Mn and Fe. Fortunately, toxic heavy metals, Pb and Cd, had the lowest contents in tea samples and also in tea aqueous extracts. Concentration of heavy metals in tea aqueous extract was markedly lower than their total contents except that of K. The solubility of studied metals in tea aqueous extract varied widely and ranged from 0.0-95%. The lowest ranges of solubility were listed for toxic heavy metals Pb and Cd. The possible uptake of metals by the human body from tea aqueous extract has also been determined. The amounts of metals that one may take up through consumption of tea aqueous extract were found to match the acceptable daily intake even taking into account exposure from air, food and drinking water.     

玉米耐盐性研究进展

综述了玉米耐盐生理机制和耐盐育种的研究进展。     

用蛭石做马铃薯快繁培养基支持体的初步研究

1　前　言目前 ,马铃薯脱毒快繁技术已广泛应用于科研与生产中 ,快繁过程中脱毒苗培养基支持体通常采用琼脂或直接采用液体培养。然而这两种培养基存在着诸多问题 ,例如琼脂培养基中的琼脂价格昂贵、成本高 ,而且胶体不利于营养物质的扩散、透气性差 ,导致瓶苗生长不良。因此 ,该实验在本着降低成本的同时 ,又能保证瓶苗正常生长的前提下 ,以蛭石代替琼脂 ,分析其在实际生产中的应用价值。2　材料与方法2 1　材料供试品种为郑薯 6号脱毒苗 ,试验于 2 0 0 2年在郑州市蔬菜研究所马铃薯脱毒实验室内进行。2 2　方法本试验设两个处理 :处理 1…     

Matlab在玉米子粒灌浆特性分析中的应用

利用Matlab软件对玉米子粒灌浆过程用Richards方程进行拟合后,通过编程实现灌浆次级特征参数计算,并对不同播期子粒灌浆特征进行分析和探讨。结果表明,在黑龙港地区生态条件下,不同播期玉米各部位子粒灌浆均符合"S"形生长曲线,可用Richards方程很好地拟合。不同播期条件下,早播处理子粒起始势最高,达到灌浆盛期时间最早,平均灌浆速率及最大灌浆速率最大,活跃灌浆期较长,粒重最高。各播期玉米不同部位子粒,穗下部与上部相比,子粒的起始生长势较大,平均灌浆速率较高,达到灌浆高峰期时间较短,粒重较高。     

5个马铃薯品种组培幼苗的磷效率差异研究

试验以5个生产用马铃薯品种脱毒试管苗为材料,采用组织培养的方法,初步研究了茎切段在正常磷及低磷培养基中生长30 d时幼苗的磷营养效率差异,为筛选出适宜于生产用的磷高效马铃薯品种奠定了基础。试验结果表明,5个马铃薯品种幼苗在正常磷和低磷胁迫下对磷素的吸收和利用能力均存在明显的基因型差异。利用各品种幼苗的磷效率指标(植株干重、鲜重、吸磷量、磷利用效率)的相对指标(低磷处理的结果/正常磷处理的结果×100)进行聚类分析(类平均法)的结果表明,大白和I-1035属于磷高效基因型品种,中农Ⅷ是磷低效基因型品种,凉薯97和疫不加则属于中间类型品种。