不同桉树品系对桉树枝瘿姬小蜂抗性研究

本研究选择了在我国主要桉树种植区内种植面积大或具有推广潜力的12个优良桉树品系,在广东肇庆、阳江和湛江3个样地进行抗桉树枝瘿姬小蜂试验,结果表明M1(Eucalyptus urophylla×E.tereticornis)、雷9(E.urophylla×E.tereticornis)为高抗品系,DH3229(E.urophylla×E.grandis)、DH3228(E.urophylla×E.grandis)、DH3226(E.urophylla×E.grandis)、LH1(E.urophylla×E.tereticornis)、金光21(E.jinguang No.21)、广3(E.wetarensis×E.marginata)和广林9(E.grandis×E.urophylla)等7个品系为抗虫品系,邓恩桉(E.dunnii)和雷11(E.urophylla×E.tereticornis)为感虫品系,Eg5(E.grandis)为高感品系。不同品系的感染虫瘿数量差异显著,Eg5的丛枝状等级较其它品系高,其它11个品系间的丛枝状等级也表现出不同程度的差异。     

桉树枝瘿姬小蜂危害程度分级方法研究

桉树枝瘿姬小蜂Lepcocybe invasa Fisher ＆ La Saller对林木的危害程度因寄主品种、侵入时间、寄主生长阶段不同而有差异。依据该虫发生区的调查结果,阐述了桉树枝瘿姬小蜂危害程度的几种分级方法,以在实际操作中完善与应用,为森防检疫、测报和防治提供依据。     

桉树枝瘿姬小蜂生物学特性及控制技术

桉树枝瘿姬小蜂Leptocybe invasa Fisher & LaSalle为2000年新发现的一新属新种,2007年在我国首次发现.该虫为桉树的重要致瘿害虫,严重为害桉树幼林和苗木,可造成巨大损失.为了采取有力预防措施,本文论述该害虫的分类地位、形态特征、生物学特性、国内外发生现状,对其进行了风险分析与评估,依据目前掌握的资料及害虫发生特点,提出了相应的控制技术.     

桉树枝瘿姬小蜂综合防控技术的研究进展

桉树是我国三大速生用材树种之一,在制浆造纸和人造板产业中发挥着重要的作用,已成为我国林业经济的重要支柱产业。然而,外来入侵害虫桉树枝瘿姬小蜂在我国南方桉树种植区大面积致瘿为害多种桉树树种,致使苗木落叶、植株矮化、枝梢枯死,严重影响桉树的生长和产量,且目前尚无有效的防治措施。鉴于此,文章综述了国内外针对其已开展的综合防控技术,提出了以林业技术和生物防治为主,化学防治为辅的观点,以期为后续针对桉树枝瘿姬小蜂的有效防控提供参考资料。     

气象因子对赣南桉树枝瘿姬小蜂成虫发生量的影响

桉树枝瘿姬小蜂在赣南发生蔓延速度很快,为摸清桉树枝瘿姬小蜂种群在赣南的发生规律及气象因子对其发生的影响,调查研究了该蜂的种群消长动态,并结合当地的主要气象因子,采用多元线性回归和逐步回归等方法对成虫发生量与气象因子的关系进行了分析。结果表明,月平均气温(x4)和月最高气温(x5)这两个气象因子对桉树枝瘿姬小蜂成虫数量有显著影响,呈显著正相关关系。最优回归方程:y=-145.579+2.503x4+5.063x5;桉树枝瘿姬小蜂成虫数量与月平均最低气温月平均最高气温、月最低温度、相对湿度虽也有一定关系,但无较大关系,均为不重要变量。     

我国发现外来入侵害虫桉树叶瘿球角姬小蜂的重要天敌——桉树扁角金绿姬小蜂（膜翅目：姬小蜂科）

近年来,在我国桉树上发生了一种严重的外来入侵害虫——桉树叶瘿球角姬小蜂Ophelimus maskelli (Ashmead)（膜翅目：姬小蜂科Eulophidae）,其在桉树叶片上形成密密麻麻的小疱状虫瘿,造成桉树叶片大量脱落。为了利用天敌对该害虫进行生物防治,我们开展了该害虫的天敌调查。通过采集受害桉树叶片进行饲养,获得了一种寄生该害虫的寄生蜂——桉树扁角金绿姬小蜂Closterocerus chamaeleon(Girault)（膜翅目：姬小蜂科Eulophidae）。该寄生蜂为我国新纪录种,本文对其形态特征进行了详细描述,并提供了成虫鉴别特征的彩色照片。桉树扁角金绿姬小蜂原产地是澳大利亚,现在已被引进到世界上许多桉树栽培的国家和地区防治桉树叶瘿球角姬小蜂,防效十分显著。桉树扁角金绿姬小蜂是自然控制该害虫的优势天敌,我国现在发现了这种天敌,将在我国生物防治这种桉树外来入侵害虫上发挥重要作用。     

水稻主栽品种对稻飞虱抗性鉴定试验

选择7个当地水稻主栽品种,设置防治与不防治处理,在相同的栽培管理条件下,开展稻飞虱抗性比较试验。结果表明,Q优1号、Y两优1号、T优111对稻飞虱抗性好,产量高,适宜大面积推广。试验结果也证明,在稻飞虱中等及偏重发生年份,只要加强水稻栽培管理,不防治稻飞虱,水稻也能获得较高产量。     

不同柑橘品种对柑橘黄龙病抗性试验

通过对芸香科12个柑橘品种人为嫁接携带柑橘黄龙病的接穗,观察接种后苗木的症状表现,测试不同柑橘品种对柑橘黄龙病的抗性和耐病性。结果表明,胡柚、金柑、佛手较为抗病,椪柑、瓯柑等较易感病。     

普通瑟姬小蜂生物学特性初步研究

首次发现普通瑟姬小蜂可寄生于构杞瘿螨虫瘿内.通过对普通瑟姬小蜂的形态特征、与构杞瘿螨种群消长规律、温度及补充营养对其寿命的影响、温度对其羽化的影响、蛹期耐冷藏性等的初步研究表明,其6月中旬对枸杞瘿螨的寄生率最高可达80.8%;成蜂寿命随温度升高逐渐缩短,补充15%蜂蜜水,可显著延长;最适羽化温度为24℃,随冷藏天数增加,羽化率逐渐降低.     

部分马铃薯主栽品种对晚疫病的田间抗性研究

为摸清贵州省低海拔地区主栽马铃薯品种对晚疫病的抗性情况,2012年对贵州省13个主栽马铃薯品种进行晚疫病抗性鉴定试验。结果表明：Z-30、BP05-003（产量在25500kg／hm2以上）对晚疫病表现为中感,为早、中熟品种,适宜在低海拔发病不重的区域推广;滇黔芋2号、米拉（产量在13500kg／hm2以上）对晚疫病表现为感病,如在晚疫病常发区、重发区种植,生产上应加大防治力度;BPHFl01、20-4．5、威薯002为中感及感病品种,产量一般,为晚熟品种,适宜在高海拔地区种植,需要加强晚疫病防治并配套高产栽培技术。     

Impact of Eucalyptus gall wasp,Leptocybe invasa infestation on growth and biomass production of Eucalyptus grandis and E. saligna seedlings in Tanzania

A study was carried out to determine the impact of Leptocybe invasa infestation on growth and biomass production of Eucalyptus grandis W. Hill ex Maiden and E. saligna Smith seedlings in Tanzania. Three- month old seedlings were infested with L. invasa. Twenty two weeks post infestation, heights of infested E. grandis seedlings were reduced by 39.6%, while diameters were reduced by 11.3% compared to uninfested seedlings. On the other hand, the heights of infested E. saligna seedlings were reduced by 38.2% and diameters were reduced 7.7% compared to uninfested seedlings. Dry weight biomass reduction of infested seedlings was significantly higher on stem and leaves than roots and branches of both E. grandis and E. saligna. The impact of L. invasa infestation on growth and biomass production was higher in E. grandis than E. saligna. Prevention and control of L. invasa infestation should be given priority. Similar future trials should examine other commercially grown Eucalyptus species in Tanzania.     

不同苜蓿品种对镰孢菌的抗性鉴定

为探明苜蓿不同品种对能引起苜蓿根腐病的茄镰孢(Fusarium solani)、半裸镰孢(F. semitectum)、弯角镰孢(F. camptoceras)等3种镰孢菌的抗性差异,提供筛选抗耐病性材料的新来源,通过室内盆栽法,对30个苜蓿品种(系)进行了苗期抗病性鉴定,结果表明,各品种之间抗病性差异显著,其中‘德里兰德’、‘新疆大叶’、‘苜蓿王’对半裸镰孢表现为抗病,病情指数分别为18.11、19.93、19.96,占鉴定总数的10%;总体来看,‘猎人河’等7个品种表现耐病,病情指数为25.30～39.95,占鉴定总数的23.3%;‘甘农2号’等18个感病品种,病情指数为40.55～59.56,占鉴定品种总数的60.0%;‘德宝’等5个品种为高感,平均病情指数为61.7~68.6,占鉴定总品种数的16.7%,无免疫和抗病品种。     

Infection and disease development of Quambalaria spp. on Corymbia and Eucalyptus species

Quambalaria spp. are eucalypt leaf and shoot pathogens of growing global importance, yet virtually nothing is known regarding the manner in which they infect and colonize their hosts. A study of the infection process of Q. pitereka and Q. eucalypti on Corymbia and Eucalyptus species was thus undertaken using light, scanning and transmission electron microscopy after artificial inoculation. Conidial germination was triggered when relative humidity levels exceeded 90% and commenced within 2 h in the presence of free water. Light reduced germination but did not prevent germination from occurring. Conidial germination and hyphal growth occurred on the upper and lower leaf surfaces with penetration occurring via the stomata or wounds on the leaf surface or juvenile stems. There was no evidence of direct penetration of the host. Following penetration through the stomata, Q. pitereka and Q. eucalypti hyphae grew only intercellularly without the formation of haustoria or interaction apparatus, which is characteristic of the order Microstromatales. Instead, the presence of an interaction zone is demonstrated in this paper. Conidiophores arose through stomatal openings producing conidia 7 days after infection.     

植物抗根结线虫机制研究进展

近年来,植物抗根结线虫机制研究已成为线虫研究领域的热点之一。本文主要从植物对根结线虫病的抗性结构、抗性基因、坏死反应以及相关酶类等方面的机制研究进展作一综述与展望。     

荒漠植物柠条根瘤菌的抗逆性及其系统发育分析

对分离自宁夏白芨滩国家级自然保护区的62株柠条根瘤菌的耐盐性、耐酸碱性、生长温度范围和抗生素抗性进行了测定,并采用16S rDNA PCR-RFLP和16S rDNA全序列分析方法对其进行了遗传多样性及系统发育分析.结果表明:柠条根瘤菌具有较强的耐受高温和耐盐、耐酸碱能力,抗逆性较强,但仍存在菌株间差异.70.8%的菌...     

功能型复合微生物菌剂防治黄瓜根结线虫的研究

根结线虫是一类重要的土传性病原物,对露地和温室蔬菜造成严重的经济损失。本研究通过平板亲和性试验,构建出一组(淡紫拟青霉、红灰链霉菌和苍白杆菌各1株)生物兼容性好、作用方式互补的功能型复合微生物菌群;以各功能菌株发酵菌体为活性成分,研制出一种防治黄瓜根结线虫的功能型复合微生物菌剂;对该复合菌剂对黄瓜根结线虫的防效及植株生物量和产量的影响进行了评价,大田试验结果表明,施用该复合菌剂的土壤线虫扩繁指数最低;移栽后38和105 d,该复合菌剂处理的根结级数分别为2.0和4.6,对病害防效为56.5%和42.5%,效果优于10%噻唑膦处理;施用该复合菌剂可以促进植株生长、增加黄瓜产量。本研究为蔬菜根结线虫病的生物防治提供了新思路。     

Diclofop-methyl resistance in populations of Lolium spp. from central Italy

Populations of Lolium spp. collected in central Italy were screened for resistance to acetyl-coenzyme A carboxylase (ACCase)-inhibiting herbicides and compared with known susceptible and resistant Lolium rigidum (Gaud.) populations from Australia. Populations Roma'94 and Tuscania'97 were up to 8- and 7.5-fold more resistant to diclofop-methyl, respectively, than susceptible populations in pot experiments. However, populations Tarquinia'97 and Vetralla'94 were not resistant. Diclofop-methyl resistance levels in the Italian populations were lower than in the Australian populations SLR31 and WLR96 (16.5 and > 64 times more resistant than S respectively). In an agar germination test, Tuscania'97 showed low levels of cross-resistance to fluazifop-p-butyl, whereas no cross-resistance was found in the Roma'94 population.     

疫霉菌对霜脲氰抗性遗传及对霜脲氰和甲霜灵的交互抗性

就疫霉菌对霜脲氰抗性的产生和遗传，以及疫霉菌对霜脲氰和甲霜灵的交互抗性进行了研究。结果表明，苎麻疫霉容易对霜脲氰产生抗药性突变，但抗性在连续３代单游动孢子分离过程中逐渐丧失。大雄疫霉对霜脲氰不易产生抗性突变，恶疫霉、大雄疫霉和苎麻疫霉对甲霜灵和霜脲氰不存在交互抗性     

Resistance to diclofop-methyl in two Lolium spp. populations from Italy: studies on the mechanism of resistance

The mechanisms of herbicide resistance were investigated in two diclofop-methyl-resistant Lolium spp. populations from central Italy, Roma '94 and Tuscania '97. These two populations were compared with two susceptible Italian populations (Vetralla '94, Tarquinia '97) and a resistant and a susceptible population from Australia, SLR31 and VLR1. The activity of acetyl Co-A carboxylase (ACCase) extracted from susceptible (S) or resistant (R) individuals from the Italian populations was inhibited by both aryloxyphenoxypropanoate (diclofop acid and fluazifop acid) and cyclohexanedione (sethoxydim) herbicides. Diclofop-methyl was rapidly de-esterified to diclofop acid at a similar rate in both R and S populations. In all populations, diclofop acid was subsequently degraded to other metabolites. The rate of degradation of diclofop acid was not significantly faster in R than in S populations; however, diclofop acid was degraded more completely in Roma '94 and Tuscania '97 compared with the S populations. Application of the mixed-function oxidase inhibitor 1-aminobenzotriazole (ABT) significantly enhanced diclofop-methyl toxicity towards both R populations, but not in S populations. However, enhanced herbicide metabolism does not completely account for the measured resistance level. A mechanism other than an altered ACCase and enhanced herbicide metabolism appears to be responsible for resistance to diclofop-methyl in Roma '94 and Tuscania '97.     

2018年湖北省小麦赤霉菌群体组成及杀菌剂敏感性检测

 由小麦赤霉菌(Fusarium spp.)引起的小麦赤霉病是小麦生产中最主要的病害之一,严重影响小麦的产量和品质。为明确目前湖北省小麦赤霉菌种群的组成、毒素化学型的分布及对杀菌剂的敏感性现状,本研究于2018年采集分离了96株小麦赤霉菌菌株,经TEF1-α基因鉴定,78株为Fusarium asiaticum,18株为F. graminearum,表明湖北省小麦赤霉菌的优势群体为F. asiaticum;利用特异性片段扩增法鉴定了菌株的毒素化学型,结果表明湖北省小麦赤霉菌菌株以3A DON化学型为主,占供试菌株群体的58%,其次为15A DON,占32%,NIV化学型最少,占10%。采用区分浓度法共检测到2株对多菌灵产生抗药性的菌株,均为F. asiaticum菌株。采用菌丝生长速率法,测定了Fusarium spp.对戊唑醇的有效抑制中浓度(EC₅₀),平均值为(0.66± 0.29)μg·mL^-1,其敏感性已经下降;其中,F. asiaticum与F. graminearum对戊唑醇的EC₅₀均值分别为(0.77± 0.26)μg·mL^-1和(0.35 ± 0.08)μg·mL^-1,表明F. graminearum群体对戊唑醇更敏感。