蝗灾同水旱灾害一样凶猛

小小的蝗虫怎么会成了灾?还被称为“天灾”,与水、旱并称三大自然灾害,因何而起,如何能治?     

蝗虫为什么能暴发成灾?

"蝗虫"因其种类多-全世界已知蝗虫超过10000种,我国已知蝗虫近900种:蝗害范围大-全球除南极洲,欧亚大陆北纬55°以北地区外均有蝗虫分布,真可谓是"虫"中之"皇"!全世界各大洲都有它们各自代表性的蝗虫,如亚洲的印度黄脊蝗、黑翅竹蝗、稻蝗等;欧洲的意大利蝗、摩洛哥蝗、小翅曲背蝗等;非洲是沙漠蝗、红蝗、塞内加尔小车蝗等等。飞蝗是一种世界分布的蝗虫。不同属种的蝗虫由于它们长期生活栖居在不同的大陆以及不同的生境场所,就具有适应各种生态条件与环境的本领,并有着不同的形态和生态学特征。     

棉蝗的发生规律及防治技术

<正> 棉蝗Chondracris rosea(De Geer)是个体较大的土蝗,雌成虫体长62～81mm。在70年代到80年代初,是我县的次要害虫,不列为主要     

笨蝗的生物学特性及防治

<正> 笨蝗Haplotropis brunneriana Sausssure是我市土蝗的优势种。近年来危害年趋加重,自1984年以来每年发生面积达10万亩以上,给农业生产带来极大危害。为此,从1987年开始作者通过人工饲养、田间调查和试验,对笨蝗的生物学特性及防治进行了初步研究,结果如下。     

中华稻蝗在冀东的危害及防治

<正> 中华稻蝗Oxya chinensis(Thunberg)是秦皇岛地区稻田蝗虫中的优势种,发生面积大,为害作物种类广泛,为历史性农作物害虫,近几年又趋严重。1986年秦皇岛地区发生38506公顷,其中,水稻被害面积25806公顷,高粱、玉米等作物被害3400公顷,苇田2100公顷,草滩7140公顷,约计损失粮食876万公斤,折款613.2万元。1987年中华稻蝗发生27400公顷,其中水稻被害20193公顷,玉米、高粱等作     

中华稻蝗对水稻危害损失及防治指标的探讨

中华稻蝗是危害水稻的主要害虫之一。1989～1990年两年,我们在抚宁县、昌黎县、唐山市东矿区进行了扣笼接虫试验,明确了不同虫口密度对水稻生长及产量的影响,得出了中华稻蝗防治的经济阈值,并初步提出了我省北部稻区的防治指标为每平方米10头。     

中华稻蝗发生规律和综合防治技术的研究

通过对中华稻蝗发生规律和综合防治技术的研究,基本上摸清了中华稻蝗在唐山的发生规律,提出了以耕翻、抹埂、铲埂、捞卵等农业措施为主,辅以人工捕捉及选用甲胺磷等化学药剂防治的综防技术,可有效地控制危害,平均每亩挽回损失近50kg,收到了明显的经济效益、生态效益和社会效益。     

中华稻蝗在水稻上危害损失及防治指标研究的商榷

中华稻蝗Oxyachinensis（Thunberg）是山西省水稻田蝗虫的仇势种。随着生态条件的改变,盐碱地改良,水稻面积逐年扩大,致使稻蝗发生越来越严重,直接影响着水稻的正常生长和产量的提高。因此,了解中华稻蝗在水稻上的危害损失,制定当地的防治指标,已成为水稻生产中急待解决的问题。为此,我们于1988～1991年进行了系统的研究,现将结果分述如下。l研究方法采用中华稻蝗三龄盛期稻田罩笼接由的研究方法,在定措农科所进行,选择肥水基本一致,前茬为水稻,亩产500kg生产水平的稻田08亩,供试品种中华11。随机区组设计,小区面积lin‘,…     

澳大利亚土著来源之谜——从最古老的人类基因分析,澳大利亚最早的移民也应来自中国(五)

前面我们曾经说过 ,许多年来 ,一些学者认为 ,除土著居民外 ,中国人可能是最先到达澳大利亚的 ,比欧洲航海家早得多 ;不论唐朝也好 ,明朝也好 ,如果那时有中国人留在澳洲 ,必是土著无疑。但是 ,这一说法现在又引发了一场新的争论 ;而且 ,对于人类起源的学说进行了新的挑战。据《光明日报》驻堪培拉记者张川杜在发回的一篇文章《澳洲人是否迁自中国引起争论》中介绍 ,新年伊始 ,澳大利亚人报在2 0 0 1年 1月 9日发表了澳大利亚国立大学考古学家索恩和他领导的研究小组的最新学术报告 ,宣称于一具在澳洲考古发现中挖掘出的远古人类骸骨中 ,发…     

The Mechanics and Trajectory Control in Locust Jumping

Locusts (Locusta migratoria manilensis) are characterised by their flying ability and abiding jump ability. Research on the jumping mechanics and behavior of locusts plays an important role in elucidating the mechanism of hexapod locomotion. The jump gestures of locusts were observed using high-speed video camera at 250 fps. The reaction forces of the hindlegs were measured using two three-dimensional sensors, in case the two hindlegs attached on separated sensor plates. The jump gestures and reaction forces were used to illustrate the locust jumping mechanism. Results show that the trajectory control is achieved by rapid rolling and yawing movements of the locust body, caused by the forelegs, midlegs and hindlegs in different jumping phases. The final jump trajectory was not determined until hind tarsi left platform. The horizontal co-impulse between two hindlegs might play a key role in jump stability and accuracy. Besides, the angle between two hindlegs affects the control of jump trajectory but has a little effect on the elevation angle of a jump, which is controlled mechanically by the initial position of the hindlegs. This research lays the groundwork for the probable design and development of biomimetic robotics.     

Neuropeptide Control of Ion and Fluid Transport Across Locust Hindgut

The anterior (ileum) and posterior (rectum) segments of locusthindgut constitute the reabsorptive part of the locust excretorysystem. They are functionally analogous to the proximal convolutedtubule and more distal parts, respectively, of the mammaliankidney tubule. Transport mechanisms are well understood in therectum, and an epithelial model has been proposed. Electrogenicactive absorption of Cl^– at the apical membrane drivesK⁺ transport (electrical coupling) and hence fluid transport(J_v). A partially purified neuropeptide (CTSH) from the CorpusCardiacum (CC) stimulates KC1 transport, and therefore presumablyfluid absorption via cAMP as second messenger. Another neuropeptide(purified and sequenced) from locust CC, neuroparsins, is reportedto stimulate rectal Jv via the inositol triphosphate (Ca²⁺)system, but actions on ion transport processes are unknown There is considerable similarity of transport processes in locustileum and rectum. A neuropeptide (ITP) acting on the ileum hasbeen purified and partially sequenced from locust CC (storagelobe). ITP has high sequence homology with a family of crustaceanneuropeptides. ITP, apparently acting via cAMP, stimulates ilealreabsorption of Cl^–, K⁺, Na⁺ and fluid by several-fold.It also inhibits active H⁺ secretion in the ileum, a processinvolved in hemolymph acid-base regulation. ITP has negligibleeffectson rectal transport processes. Thus separate neuropeptides apparentlycontrol transportevents in locust ileum and rectum.     

Locust flight steering

Locusts (Locusta migratoria) were flown in a flight simulator which converts yaw torque into angular motion of the visual environment (Fig. 1). The modalities and the time-course of steering behavior under these closed-loop conditions have been investigated.

蝗虫的发生与防控

蝗虫暴发引起的灾害是全球重要的生物灾害,可影响到全世界十分之一的人口。自2019年,东部非洲、西亚、南亚多个国家遭遇严重的沙漠蝗虫灾害,这场蝗灾不但对该区域的粮食安全构成严重威胁,而且还有可能引发严重的人道主义危机。为了制定合理的防治方案,实施有效防控,避免大规模蝗灾的发生,需要掌握蝗虫的生物学、生态学、暴发和为害规律、防治策略和技术特点及其进展等。本文介绍了世界各地包括沙漠蝗、飞蝗、澳大利亚疫蝗在内的11种可以引起灾害的重要种类的主要分布、为害和特性,并对国内外蝗虫防治策略、技术进展进行了重点综述。最后,针对目前蝗虫防治存在的问题提出了相应建议。     

An American naturalist's impressions on Australian biodiversity and conservation

Editorial Introduction

An American naturalist's impressions on Australian biodiversity and conservation