应用绿僵菌油剂防治内蒙草原蝗虫的效果

1999年在内蒙古草原进行了用绿僵菌油剂超低量喷雾防治蝗虫的试验.结果表明,对5种蝗虫(亚洲小车蝗、红翅皱膝蝗、毛足棒角蝗、白边痂蝗、轮纹异痂蝗)的防效显著.喷药后8天,对主要蝗虫亚洲小车蝗(占混合虫口的92.2%)的防效达48.0%,12天后增至88.1%.蝗虫死亡后2～3天,失水形成僵虫;7～10天虫尸上出现绿色粉状的绿僵菌孢子.孢子的扩散有可能继续起着控制蝗虫虫口的作用.     

绿僵菌在不同类型草原防治蝗虫的效果分析

金龟子绿僵菌是一种对靶标昆虫具有高毒力和致病性的重要杀虫真菌,通过接触直接侵染使蝗虫致死,对草原蝗虫治理具有重要意义。本试验研究了不同类型草原喷施金龟子绿僵菌粉剂对蝗虫的防治效果。结果表明,金龟子绿僵菌对蝗虫有较好的防治效果,喷药后7 d优势种蝗虫毛足棒角蝗Dasyhippus barbipes、亚洲小车蝗Oedaleus decorus asiaticus和宽须蚁蝗Myrmeleotettix palpalis的虫口减退率达60%、防治效果超过62%,其中白边痂蝗、毛足棒角蝗、亚洲小车蝗和宽须蚁蝗的虫口减退率和防治效果均高于宽翅曲背蝗Pararcyptera microptera meridionalis和轮纹异痂蝗Bryodemella tuberculatum dilutum;同时,金龟子绿僵菌在不同类型草原的防治效果存在差异,在典型草原和荒漠化及半荒漠化草原的防治效果高于草甸草原。研究绿僵菌在不同草原类型蝗虫的防治效果,为建立草原蝗虫绿色可持续防控体系提供支持。     

应用绿僵菜油剂防治内蒙草原蝗虫的效果

１９９９年在内蒙古草原进行了用绿僵菌油剂超低量喷雾防治蝗虫的试验。表明,对５种蝗虫（亚洲小车蝗、红翅皱膝蝗、毛足棒角蝗、白边痂蝗、轮纹异痂蝗）的防效显著。喷药后８天,对主要蝗虫亚洲小车蝗（占混合虫口的９２．２％）的防盗和达４８．０％,１２天后增至８８．１％。蝗虫死亡后２～３天,失水形成僵虫,７～１０天虫尸上出现绿色粉 绿例题菌孢子。孢子的扩散有可能继续起着控制蝗虫虫口的作用。     

内蒙古典型草原蝗虫群落结构和生态位研究

采用定点调查和生物量定量分析方法对内蒙古典型草原不同草地蝗虫群落结构和生态位进行研究,结果表明,典型草原蝗虫群落结构丰富,主要蝗虫有11种,草原蝗虫的时间分布揭示了蝗虫时间生态位的分化,宽须蚁蝗[Myrmeleotettix palpalis(Zubowsky)],亚洲小车蝗(Oedaleus decorus asiaticus B.-Bienko)、短星翅蝗(Calliptamus abbreviatus Ikonnikov)分别构成镶黄旗草原蝗虫早期、中期、晚期优势种;根据蝗虫种群地位,将11种蝗虫划分为优势种、附属种、稀少种,把11种蝗虫按空间地位划分为禾草地类、荒草类、特殊类和全域类4类,优势种蝗虫的种群与空间地位,反映了蝗虫与植被、蝗虫与蝗虫之间关系。优势种蝗虫中短星翅蝗的时空生态位宽度最大,其次是亚洲小车蝗和宽须蚁蝗,说明短星翅蝗对时空"资源"的利用程度最高,共存的蝗虫种类在"资源"利用上存在着明显的分化,亚洲小车蝗与宽须蚁蝗的生态位重叠最大,说明两者利用资源的相似性程度最高。我们用生态位来体现蝗虫种群地位及对资源的利用,同时也用资源的系统聚类来预测蝗虫的潜在发生与危害。本文系统地研究了蝗虫群落结构和蝗虫生态位,将为评价草原蝗虫潜在发生与危害、蝗虫宜生区划分和制定草原有害生物防治策略提供理论基础。     

青海省和内蒙古草原蝗虫痘病毒自然资源调查

为了解我国草原蝗虫中昆虫痘病毒的自然分布情况,于2018年、2019年和2021年在青海省环青海湖地区和内蒙古自治区太仆寺旗共采集8种优势蝗虫,通过镜检手段、巢式PCR技术以及蔗糖梯度离心法鉴定、检测并提取昆虫痘病毒,并测定其对宿主的致死效果。结果表明,在青海省分布的白纹雏蝗Chorthippus albonemus、狭翅雏蝗Chorthippus dubius和在内蒙古自治区分布的毛足棒角蝗Dasyhippus barbipes、锡林蛛蝗Aeropedellus xilinensis四种蝗虫中检测到昆虫痘病毒,自然感染率在5.19%~34.65%之间;其中在毛足棒角蝗种群中检测到的昆虫痘病毒自然感染率最高,为34.65%;其次是采集自同一地区的锡林蛛蝗,昆虫痘病毒自然感染率为20.00%;青海省分布的狭翅雏蝗和白纹雏蝗种群中昆虫痘病毒自然感染率较低。从毛足棒角蝗中分离出有较高致病性的昆虫痘病毒,饲喂该病毒处理小麦叶片后10 d毛足棒角蝗4龄若虫的存活率低于10.00%,表明该病毒具有开发为蝗虫生物防治制剂的潜力。     

亚洲小车蝗在不同生境中的群落动态研究

亚洲小车蝗(Oedaleus decorus asiaticus B.Bienko)是内蒙古草原主要的蝗虫危害种,为了研究其在不同生境中的动态规律,在内蒙古锡林郭勒盟镶黄旗,采用野外剪样方和扫网的方法,研究了亚洲小车蝗发生时,不同生境中植物与蝗虫种群结构的变化,并进行了室内食量验证.结果表明,亚洲小车蝗数量同植物盖度呈负相关(R=-0.770 8,P＜0.01),同植物生物量呈负相关(R=-0.905 2,P＜0.01),草场中蝗虫多样性同植物多样性呈正相关(R=0.588 4,P＜0.05);蝗虫总数同植物盖度呈负相关(R=-0.759 3,P＜0.01),同植物生物量呈负相关(R=-0.859 7,P＜0.01);羊草为优势种的样地中蝗虫数量少于针茅为优势种的样地;室内饲养表明,小车蝗对羊草的消耗量大于针茅(P＜0.05);以上结果说明,亚洲小车蝗选择草场时优先选择合适的栖境而不是食料植物.亚洲小车蝗的防治重点应放在适合小车蝗栖息的地点,而不仅是食料植物为主的地区.     

高山草原主要蝗虫的生物学特性

据１９８９￣１９９４年的调查研究,甘肃夏河县革加高山草原共有蝗虫３０余种,其中主要种类有狭翅雏蝗、宽须蚁蝗、红翅皱膝蝗鼓翅皱膝蝗、小翅雏蝗和邱氏异爪蝗根据发生时期的不同,可将草地蝗虫划分为早、中、晚３种类型。蝗蝻的发育历期在种类之间差异较大以早期发生的宽须蚁蝗最长,而晚期发生的小翅雏蝗最短。从孵化到成虫死亡所经历的时间,以晚期发生的种类最短。狭翅雏蝗的繁殖力在６种蝗虫中最高,每雌产卵量平均达１２５     

新疆博尔塔拉蒙古自治州草原蝗虫多样性及群落结构特征

2015―2018年,利用百网和“Z”形取样法系统调查了博尔塔拉蒙古自治州草原七个草地类型的蝗虫群落多样性,明确其蝗虫的群落结构特征和多样性组成。经过调查分类鉴定,确定博州草原蝗虫有 65种,隶属于5科30属,优势种为黑腿星翅蝗、黑条小车蝗和小米纹蝗。在博州,黑条小车蝗垂直海拔分布的范围最广（257～2382 m）,亚洲飞蝗和绿纹蝗垂直海拔的分布范围最为狭窄,仅为187～195 m;小翅曲背蝗和西伯利亚蝗多分布于高海拔地区（2000～2200 m）,红斑翅蝗则多分布于低海拔区域（750～1200 m）。温性荒漠的特有种为简蚍蝗、红翅瘤蝗和红斑翅蝗,低地草甸的特有种为亚洲飞蝗、小垫尖翅蝗和绿纹蝗。蝗虫群落的Shannon-Wiener多样性指数在温性荒漠、温性草原化荒漠和温性荒漠草原要显著高于低地草甸;Pielou均匀度指数和Simpson优势度指数在七个草地类型间无显著性差异。温性荒漠草原和温性草原的蝗虫群落最为相似,两者Jaccard相似系数为0.56。     

高山草地蝗虫群落生物多样性和空间聚集强度对植物群落的响应

为明确高山草地蝗虫群落生物多样性和空间聚集强度变化及其对植物群落的响应,在位于甘肃省祁连山中段北坡的研究区调查温性草原、山地草甸和高寒草甸3类草地中的蝗虫种类和数量,对不同蝗虫群落进行生物多样性分析,并观察不同蝗虫种群的聚集程度。结果显示,共捕获蝗虫15种,8月温性草原内蝗虫虫口密度最大,为8.17头/m²,且此时Shannon-Wiener指数和Margalef丰富度指数均最大,分别为1.58和2.27;7月蝗虫群落的空间聚集程度高于其他两类草地。山地草甸和高寒草甸中蝗虫空间聚集高峰出现在8月,晚于温性草原。东亚飞蝗Locusta migratoria manilensis种群的空间聚集程度最高,其次为白边痂蝗Bryodema luctuosum、狭翅雏蝗Chorthippus dubius和小翅雏蝗Chorthippus fallax种群,鼓翅皱膝蝗Angaracris barabensis种群的聚集程度最弱。冗余分析结果显示,蝗虫群落种类组成和数量以及空间聚集强度与植物群落生物多样性、覆盖度和高度存在显著相关性。     

群居型、散居型亚洲小车蝗形态特征的数量分析

亚洲小车蝗(Oedaleus decorus asiaticus Bei-Bienko)是草原蝗虫的主要优势种之一,为了明确亚洲小车蝗两型现象与形态特征的关系,本文利用11个形态指标和5个形态指标比值采用数值分类学的方法对两型亚洲小车蝗成虫进行了测量和分析。结果表明,11个形态指标在亚洲小车蝗种群中均表现出一定的差异性,与能量储存、运动和飞行相关的体长(L)、前翅长度(E)、后足股节长度(F)在群居和散居型种群中具有极显著性差异(P0.01)。形态指标比值中,前翅长度和后足股节长度的比值(E/F)对两型蝗虫区分效果明显,群居型亚洲小车蝗成虫的E/F比值在1.68~1.74之间,散居型成虫的E/F比值在1.44~1.59之间,群居型E/F比值显著大于散居型(P0.05)。主成分分析构建了3个反映形态特征及其比值信息的综合指标,前两个主成分累积贡献率为99.84%,同时确定了E/F比值在两型区分上具有重要的指示作用,可以作为亚洲小车蝗成虫两型现象的判定指标。     

Competition,spatial pattern,and regeneration of Haloxylon ammodendron and Haloxylon persicum communities in the Gurbantunggut Desert,Northwest China

Competition, spatial pattern, and regeneration are important factors affecting community composition, structure, and dynamics. In this study, we surveyed 300 quadrats from three dunes (i.e., fixed dunes, semifixed dunes, and mobile dunes) in the Gurbantunggut Desert, Northwest China, from late May to early June in 2021. The intraspecific and interspecific competition, spatial pattern, and regeneration of Haloxylon ammodendron and Haloxylon persicum were studied using the Hegyi competition index and point pattern analysis methods. The results showed that the optimal competition distance of the objective tree in the H. ammodendron and H. persicum communities was 6 m. The intraspecific and interspecific competition of H. ammodendron was the greatest in fixed dunes, while the competition intensity of H. persicum in semifixed dunes and mobile dunes was greater than that in fixed dunes. The order of competition intensity of the two populations was seedlings>saplings>adults, and the competition intensity gradually decreased with the increase in plant diameter. The spatial distribution pattern of the three life stages of H. ammodendron and H. persicum was random, and there were no correlations between seedlings and saplings, adults and saplings, and seedlings and adults. The density of regenerated seedlings and saplings of H. ammodendron in the three dunes followed the order of fixed dunes>semifixed dunes>mobile dunes, and that of H. persicum in the three dunes followed the order of mobile dunes>semifixed dunes>fixed dunes. Therefore, when artificially planting H. ammodendron and H. persicum for sand control, the planting interval should be 6 m, and seedlings should be planted next to adults to minimize the competition between plants, which can promote the renewal of H. ammodendron and H. persicum and the stabilization of the ecosystem.     

Quantitative evaluation of wheat against volunteer rye in Iran

Rye infestations have increased in frequency and severity in the wheat fields of Iran and have caused yield reductions in wheat production. In order to study the competition effects of wheat against rye, an experiment was conducted at the research centers of Karaj and Varamin, Iran, during 2001 and 2002. The experimental design was a randomized complete block with 24 treatments and four replications. The treatments included pure stands of wheat at densities of 350, 450, 550, and 650 plants m⁻² and volunteer rye densities of 10, 30, 50, and 70 plants m⁻², and mixed stands of wheat and rye at complete factorial densities. The results indicated that rye was a superior competitor compared to wheat. The biological and economic yields of wheat were mainly affected by interspecific competition in the Karaj region. This was also true during the first year in the Varamin region but, in the second year, the biological and economic yields of wheat were equally affected by interspecific and intraspecific competition because of increasing precipitation. The evaluation of competitive ability, using regression coefficients, showed that in Karaj, the effect of one rye plant on wheat was approximately equivalent to three and two plants of wheat in reducing the grain yield of wheat in the first and second years, respectively, while in Varamin, it was equivalent to three and 1.2 plants of wheat, respectively. In other words, each 0.36 and 0.51 rye plant in Karaj and each 0.36 and 0.84 rye plant in Varamin had the same impact on the reciprocal wheat grain yield as did one wheat plant in the first and second years, respectively.     

Competition between Imperata cylindrica and maize in the forest savannah transition zone of Nigeria

Imperata cylindrica is a noxious weed that infests annual and perennial crops in most tropical regions. High crop densities may offer opportunities to reduce I. cylindrica competition in small‐scale farming systems. The competitive ability of maize relative to I. cylindrica was evaluated in an addition series experiment in the forest savannah transition zone in 2006 and 2007 at Ibadan, Nigeria. Maize and I. cylindrica were planted in eight monoculture densities (4, 8, 12, 16, 20, 32, 48 and 64 plants m^?2) and in a 1:1 mixture at eight total densities (2:2, 4:4, 6:6, 8:8, 10:10, 16:16, 24:24 and 32:32 maize: I. cylindrica plants m^?2) as in monoculture. Non‐linear regression models were used to relate crop and weed shoot biomass to their densities and total grain yield to maize density. In maize, intraspecific competition was more than interspecific competition; in I. cylindrica, interspecific competition was higher than intraspecific. As expected, total grain yield was lower in the mixture than in maize monoculture at all total densities. Average maize grain yield in maize monoculture differed from that in mixtures by 0.77 t ha^?1 in 2006 and 0.57 t ha^?1 in 2007. Niche differentiation indices were <1 in 2006 and >1 in 2007, indicating that both species competed for similar resources in 2006, but not in 2007. The greater competitive ability of maize over I. cylindrica may be associated with rapid growth and canopy development observed in the field.     

取食不同牧草对亚洲小车蝗发育速率和类胰岛素信号通路的影响

亚洲小车蝗是重要的草地生物灾害,对不同牧草的食物适应存在差异。为揭示不同牧草对亚洲小车蝗生长发育的影响机理,本研究定量分析了取食不同牧草条件下亚洲小车蝗的发育速率和类胰岛素信号通路(ISP)基因表达。结果表明,西北针茅饲喂的亚洲小车蝗发育速率最高,ISP通路中gIGF1、gINSR、gIRS1、gPI_3K、gAKT及gmTor基因表达显著上调(P0.05),调控下游发育和代谢相关的表皮蛋白(cuticle protein, gLCP)、胰凝乳蛋白酶(chymotrypsin, gCHY)及α-葡萄糖苷酶(α-glucosidase, gALP)基因表达上调。相反,冷蒿饲喂的蝗虫发育速率显著降低(P0.05),上述基因显著下调(P0.05),调控下游解毒相关的gP450s 6K1、gUDP 2C1及gCarE基因表达上调。亚洲小车蝗ISP通路响应食物差异,调控发育速率,以适应更广泛的生态区域,这可能是其分布广、易暴发成灾的原因之一。     

草地贪夜蛾和亚洲玉米螟种内及种间的竞争行为

草地贪夜蛾Spodoptera frugiperda (J.E.Smith)和亚洲玉米螟(以下简称“玉米螟”)Ostrinia furnacalis (Guenée)是玉米上的重要害虫, 二者在玉米田常混合发生, 存在对食物和空间资源的竞争关系。为探明草地贪夜蛾和玉米螟种内和种间竞争的行为表现, 本文在食物缺乏条件下, 研究了草地贪夜蛾和玉米螟种内和种间的攻击和防御行为。结果表明:草地贪夜蛾种内攻防行为中头部接触是最主要的行为表现, 其中6龄与6龄以及6龄与5龄幼虫竞争时头部接触行为出现次数最多, 在20 min内分别为(17.8±1.7)次和(15.3±1.1)次。玉米螟种内攻防行为中畏缩行为是最主要的行为表现, 在5龄与5龄幼虫的竞争中出现频率最高, 为(14.8±0.7)次。〖JP3〗草地贪夜蛾和玉米螟种间竞争行为中, 二者都主要表现为头部接触行为, 但草地贪夜蛾攻击行为表现更明显。此外, 从存活率上看, 同一龄期的玉米螟和草地贪夜蛾种间竞争中, 草地贪夜蛾具有明显优势; 不同龄期的玉米螟与草地贪夜蛾种间竞争中, 同一组合中龄期相对较高的幼虫具有明显竞争优势。研究结果可为明确草地贪夜蛾和玉米螟的种群优势及制定相应的防治策略提供参考。     

The influence of the nematode Meloidogyne incognita on competition between Solanum nigrum and tomato

The effect of Meloidogyne incognita (Kofoid & White) Chitwood, 1949, on the competitive relationship between tomato (Lycopersicon esculentum Mill.) and black nightshade (Solanum nigrum L.) was investigated under glasshouse conditions. Two intraspecific competition treatments were set up for the crop and the weed, and five interspecific treatments where the emergence of S. nigrum plants was progressively delayed in relation to tomato. Nematodes reproduced in all inoculated plants, their multiplication rates being much higher in tomato than in S. nigrum plants. Under nematode-free conditions, intraspecific competition of tomato was more severe than the interspecific competition shown by the weed S. nigrum. Tomato was as tronger competition with S. nigrum than the weed was with itself. However, when infested by M. incognita, both species displayed a similar competitive ability. Tomato yield losses increased with prolonged weed competition but were greater under nematode-infested conditions.     

牧场蝗虫复合防治指标的研究

１９９２－１９９３年，作者对甘肃农垦宝瓶河牧场冬春季草声蝗虫优势种华北雏Ｃｈｏｒｔｈｉｐｐｕｓ ｂｒｕｎｎｅｕｓ ｈｕａｂｅｉｅｎｓｉｓ Ｘｉａ ｅｔ Ｊｉｎ、鼓翅皱膝蝗Ａｎｇａｒａｃｒｉｓ ｂａｒａｂｅｎｓｉｓ （Ｐａｌｌ）、青海痂Ｂｒｙ铮洌澹恚? ｍｉｒａｍａｅ ｍｉｒａｍａｅ Ｂ．－Ｂｉｅｎｋｏ对牧草造成的为害程度及混合为害时的防治指标，即复合防治指标进行了研究，建立了华北雏蝗密度与牧草损失     

温度对美洲斑潜蝇和南美斑潜蝇种间竞争的影响

为明确温度对美洲斑潜蝇和南美斑潜蝇种间竞争的影响,在试验玻璃筒中同时接入两种斑潜蝇各1♀1♂,置于不同温度(18、25、30℃)下培养,观察两种斑潜蝇子代的化蛹数、成虫数及羽化率.结果显示,18℃下,美洲斑潜蝇的F1代成虫数仅为(0.4±0.3)头,显著低于南美斑潜蝇的(2.5土0.7)头;25℃下,美洲斑潜蝇的F1代成虫数(7.6±3.0)头,稍高于南美斑潜蝇的(4.3±2.0)头,但不存在显著差异;30℃下,美洲斑潜蝇的F1代成虫数为(18.0±2.9)头,而F1代中无南美斑潜蝇成虫.说明温度对两种斑潜蝇的种间竞争具有重要影响.     

Influence of corn density and planting pattern on the growth of common lambsquarters (Chenopodium album L.)

Crop density and spatial arrangement affect the potential of intraspecific and interspecific competition as they increase the canopy light absorption. The effects of the corn density and planting pattern on the growth of common lambsquarters ( Chenopodium album L.) was studied in a randomized, complete block design with three replications and factorial arrangement at University College, Aburaihan, Iran, in 2003. The plant density was the recommended density and 1.5-fold the recommended density. The planting pattern treatment also was performed at two levels: one- and two-row planting. The common lambsquarters density was 0, 5, 10, and 15 plants m⁻¹ per row. The results showed that the leaf area index, biomass production, crop growth rate, and inflorescence biomass of the dry matter of common lambsquarters were decreased by increasing the corn density. But, the leaf area index, biomass production, crop growth rate, and inflorescence biomass of the dry matter of common lambsquarters under the two-row planting pattern were less than under the one-row planting pattern, although these differences were not significant.