菜粉蝶的发生为害调查及测报方法探讨

菜粉蝶Pieris rapae（Linnaeus）在梧州市1a发生7～8代，该虫主要发生危害时期为春、秋两季.在高温的5～7月卵的孵化率较低，一般为10%～30%.当田间橙黄色卵粒数达总卵量数30%之后2～3d即为幼虫盛发期;以小白菜为例，其防治指标是：苗期1000～1 500头幼虫/667m^2，成株期～中后期20～30头幼虫/百株。     

土沉香黄野螟生物学特性研究

黄野螟(Heortia vitessoides Moore)是土沉香的主要害虫.通过室内、外的观察,结果表明,土沉香黄野螟1年可以发生6代.11月下旬以老熟幼虫入土化蛹越冬.翌年4月初羽化.成虫趋光性弱.26℃条件下,卵期6.6 d,幼虫期14.1 d,预蛹期2.9 d,蛹期9.8 d,雌、雄成虫寿命分别为8.7和8.6 d.幼虫共5龄,1～4龄具群集性,5龄的取食量占幼虫期的70.24％.卵主要分布于寄主树冠下层嫩叶端部的背面.     

黑广肩步甲主要生物学特性及卵的有效积温

研究了黑广肩步甲Calosoma maximociczi Morawitz各虫态的主要生物学特性及其卵的发育起点温度与有效积温。在山东地区,该虫1年发生1代,以成虫在土壤中越冬。成虫在5月中旬至10月上旬发生,6月初开始产卵,卵的发育起点温度为14．66℃,有效积温41．7日度,在25℃下卵期平均为3．69±0．25d;幼虫共3龄,历期分别为3d～5d、4d-5d;平均气温28℃下,预蛹期约为8d-14d,蛹期为10d-15d。成、幼虫以多种鳞翅目幼虫为食。     

黑纹粉蝶的生物学

黑纹粉蝶PierismeleteMenetries是江西山区十字花科蔬菜上的重要害虫，目前只发现在萝卜、白菜和芥菜上为害，以幼虫取食叶片和荚果。该虫在江西一年发生2～4代，春季1代，以蛹越夏，秋季1～3代，以蛹越冬。由于越夏代成虫的羽化期和产卵期长，导致了世代重叠。雌虫寿命一般7～15d，每雌产卵量可达200粒；卵单产于叶片背面，卵期3～8d；幼虫期12～26d；非滞育的蛹期7～24d，越夏的蛹期104～178d，越冬的蛹期97～157d。     

异距琵甲(鞘翅目:拟步甲科)生物学特性的研究

异距琵甲在宁夏2年发生1代,以成虫和不同龄期的幼虫越冬,4月上旬至10月上旬产卵,卵期10～14 d,幼虫一般为12龄,幼虫期380～445 d;越冬幼虫于次年6月下旬至9月上旬化蛹,蛹前期16～28 d,蛹期14～20 d,羽化成虫经240～275 d性成熟开始交配产卵。该虫食性杂,不喜光,活动有明显的节律性。成虫具防御腺进行自卫,防御腺分泌物可作药物应用。     

低温对棉铃虫卵和蛹生物学特性的影响

将棉铃虫卵和蛹在(9±0.5)℃低温下处理不同时间 ,结果表明 ,卵处理1～6d的幼虫孵化率为88.4%～66.2% ,处理7～9d的为55.9%～22.0% ;蛹处理1～5d的成虫羽化率显著高于处理6～7d的 ;蛹的历期以处理 5d以内的成虫羽化高峰期较为接近。试验结果对棉铃虫的抗药性研究具有重要作用。     

绿翅绢野螟生物学特性初步研究

绿翅绢野螟[Diaphania angustalis(Snellen)]是糖胶树的主要害虫。幼虫吐丝纵卷叶片取食叶肉。在云南思茅1年发生6代,第2～4代为主害代。以老熟幼虫在糖胶树上越冬。卵期3.5～4.5 d,幼虫期15.5～18.4 d,蛹期10.8～13.9 d,雌成虫期12～16.3 d,产卵前期4.6～7.5 d,产卵期5～8 d。以生物农药为主的综合防治措施,能有效防治。幼虫寄生蜂寄生率高。     

蓼科杂草的重要天敌——蓼蓝齿胫叶甲

蓼蓝齿胫叶甲是蓼科杂草的重要天敌 ,以成虫、幼虫取食寄主叶片、叶柄和和植株生长点 ,导致全株枯死。该虫在宜昌 1年发生 1代,2月底至 3月初成虫出蛰取食、交配产卵 ,3月中旬始见幼虫,4月上旬至 6月上旬老熟幼虫入土化蛹 ,4月中旬以后成虫陆续羽化 ,以未交配成虫在土壤中越夏越冬。该虫历期卵7～10d ,幼虫10～20d ,蛹5～10d ,成虫期长达1年之久     

椴六点天蛾形态特征及生物学特性

通过室内饲养观察和田间调查对发生在广东湛江的椴六点天蛾形态特征和生物学特性进行了研究。结果表明,椴六点天蛾1年发生6～7代,且世代重叠,主要以蛹越冬。世代历期51～73 d。其中,卵期5～7 d,幼虫期29～41 d,蛹期16～25 d,成虫寿命8～14 d。成虫具趋光性。产卵期4～6 d。卵多散产于叶背面。每雌产卵129～264粒。幼虫共6龄,3龄后食量暴增,4龄时体色分化为绿色和橙色2种明显的色型,大多数为绿色型,老熟幼虫在土中化蛹。     

水葫芦象甲的生物学及其寄主专一性

在室温 2 5～ 2 8℃的养虫室内 ,水葫芦象甲雌成虫寿命最长可达 1 6 1d ,最大卵量为 1 0 91粒。产卵期为 2 0～ 1 59d。卵主要产在叶柄内。幼虫孵化后在叶片内和叶柄中取食 ,并向植株基部钻蛀。幼虫期 30～ 4 0d。老熟幼虫在活的水葫芦植株根部化蛹 ,蛹期 2 5～ 30d。在温州自然条件下 ,象甲年发生 2代 ,并有明显的世代重叠现象。以成虫和幼虫越冬。利用 2 3科 4 6种植物进行的寄主专一性测定发现 ,该象甲只为害水葫芦 ,可安全用于水葫芦的生物防治     

松材线虫自然侵染后对不同松树组织结构的影响

 利用滑走切片技术从显微水平研究松材线虫（Bursaphelenchus xylophilus）在自然状态下入侵,对马尾松（Pinus massoniana）和黑松（Pinus thunbergii）显微结构的影响。结果表明,马尾松和黑松的组织结构在感病初期即表现出病变特征,并随感病时间推移病变加剧。马尾松在感病初期皮层薄壁细胞开始木质化,伴有细胞破裂并融合成空腔;至感病中期周皮的栓内层细胞、皮层薄壁细胞以及韧皮部薄壁细胞均发生木质化,细胞内含物增多,甚至形成层细胞也发生一定程度的木质化现象,树脂道因周围细胞破裂而变形;至感病晚期,木材以外所有部分完全被木质化、大量细胞破裂。黑松发病症状与马尾松大致相同但发病时间稍晚,发病程度也较轻,这可能是因为两者对松材线虫病的抗性强弱有差异。同一时期的组织病理学特征在空间上也存有差异,这与松材线虫入侵的位置及其在树体内的分布有关。     

松阳县古松树的松材线虫病现状调查与分析

古松树是历史的见证,是文化的承载,其保护工作具有重要意义,但因松材线虫的传播侵染,其生存状况不容乐观。本研究以松阳古松树为对象,基于分子检测技术,对其松材线虫病现状进行了调查与分析。结果表明,有12个乡镇近60%的古松树均已感病,疫情较为严重,需及时开展抗病保护工作。     

Enhancement of sphaeropsis canker of aleppo pine by the Israeli pine bast scale

An interaction between the fungal pathogenSphaeropsis sapinea (Fr.) Dyko & Sutton, causal organism of Sphaeropsis canker, and the Israeli pine bast scaleMatsucoccus josephi (Homoptera: Margarodidae), causal agent of pine decline, was studied, since both were prevalent on Aleppo pine (Pinus halepensis) stands.Sphaeropsis sapinea was isolated from larvae (stage II) and molts of the Israeli pine bast scale collected in four Aleppo pine stands. When Aleppo pine saplings were infested with pine bast scale and subsequently inoculated withS. sapinea most plants died, whereas mortality of seedlings inoculated withS. sapinea alone without previous scale infestation was negligible. Scale infestation of saplings without subsequent fungal inoculation caused the death of one third of the plants. Wounding of pine shoot apices by removal of needle fascicles enhanced infection byS. sapinea. The results support the assumption thatM. josephi can play an important role in transmitting the fungal inoculum to the host tree as well as enabling its penetration to the shoots through wounds in the bark. http://www.phytoparasitica.org posting Dec. 20, 2004.     

马尾松松材线虫病与松材蓝变相关性研究

 研究表明:松材线虫引起的马尾松(Pinus massoniana)病树死亡后期,必然有蓝变(Blue-stain)现象。松材蓝变程度与松树树干部位相关性不大。但是,对于同一棵树,若蓝变程度高,则每一部位的蓝变程度都比较高;若蓝变程度低,则每部位的蓝变程度可能都比较低。蓝变程度与松材线虫(Bursaphelenchus xylophilus)的含量也没有正相关关系。在松材线虫病木的检疫过程中,松木蓝变仅可以作为松材线虫病的参考指标。     

Induction of resistance against pine wilt disease caused by Bursaphelenchus xylophilus using selected pine endophytic bacteria

Pine wilt disease (PWD) is the most destructive disease threatening pine worldwide. The disease is mainly caused by the pine wood nematode, Bursaphelenchus xylophilus, which is vectored by pine sawyer longhorn-beetles, Monochamus spp. This study aimed to select resistance-inducing pine endophytic bacteria for management of PWD. To set up a defence-related genes expression pattern for screening, four chemical inducers (salicylic acid, γ-aminobutyric acid (GABA), β-aminobutyric acid and α-aminobutyric acid) were tested in vitro on pine calli and in vivo on pine seedlings. Treatment with GABA had the greatest reduction in PWD severity on pine seedlings. The pattern of defence-related gene expression in calli treated with GABA was used to select potential resistance-inducing bacterial strains. In addition, 92 bacterial strains were isolated from pine tree needles and stems and were tested for expression of defence-related genes in pine calli in vitro. Among the tested strains, 13 showed a similar pattern to GABA treatment in at least four tested defence-related genes and were selected for the seedling assay. From the seedling assay, three bacterial strains (16YSM-E48, 16YSM-P180 and 16YSM-P39) showed significant reduction in PWD severity compared to the untreated control. Moreover, among the selected strains, cell-free culture supernatant of strain 16YSM-P180 significantly reduced PWD severity in inoculated pine seedlings. The selected strains were identified based on the 16S rRNA sequence as Pseudomonas putida 16YSM-E48, Curtobacterium pusillum 16YSM-P180 and Stenotrophomonas rhizophila 16YSM-P39. These selected strains are suggested as potential alternatives for management of PWD by induction of systemic resistance.     

Relationship between resistance to pine wilt disease and the migration or proliferation of pine wood nematodes

To study the relationship between resistance to pine wilt disease and the migration or proliferation of pine wood nematodes (PWN) (Bursaphelenchus xylophilus), we conducted experiments using clonally-propagated Japanese black pines (Pinus thunbergii) with pre-evaluated individual resistance levels. Bark including the cortical resin canals—one of the main migration pathways of PWN—was removed by girdling, but neither the migration of PWN nor symptom development of pine wilt disease were inhibited by this treatment in non-resistant clones. Histological observations showed no significant differences in the lumen area or the number of cortical- and xylem- axial resin canals between resistant and susceptible clone groups from a half-sib family. A bioassay using methanol extracts from resistant and susceptible clones showed that extracts from both clones showed similar attractant effects to PWN, but neither had repellent effects. The resistant clones were multi-inoculated with PWN into three split points to mimic migration in the stem. The proportion of damaged plants was not significantly different from that in single-inoculated plants (control). In this experiment, the number of PWN detected from partially-damaged plants was much higher than that from non-damaged plants. An inoculation test using stem cuttings showed that the population of PWN increased in susceptible cuttings at 1–20 days after inoculation (dai), while it remained unchanged or gradually decreased in resistant cuttings. These findings suggested that the factors contributing to resistance were associated with inhibiting the proliferation of PWN, rather than inhibiting their migration.     

松材线虫病取样部位及检测技术初探

本文介绍了从松材线虫病疫木的不同高度进行取样和分离,通过传统病原形态学方法进行检测和计数的技术,探讨松材线虫在松树体内的数量分布情况,从而提高松材线虫的检出率和缩短检疫时间.     

Temporal variation in contamination of pine engraver beetles with Fusarium circinatum in native Monterey pine forests in California

The relative importance of beetle species associated with Fusarium circinatum‐infected Monterey pines was investigated in three Monterey pine forests along the coast of central California, USA from April to November in 2004 and 2005. Fusarium circinatum was frequently isolated from Ips mexicanus and I. plastographus. The mean percentage isolation based upon numbers of I. mexicanus and I. plastographus carrying propagules of F. circinatum was 17·7 and 10·9% in 2004 and 16·7 and 17·3% in 2005, respectively. The mean percentage isolation was high in the spring and early summer and low in late summer and autumn in all three locations for both species. Isolation was higher from beetles emerging from harvested F. circinatum‐infected pine‐stems than for trapped beetles, 42·4% for I. mexicanus and 45·9% for I. plastographus. The mean (± SE) propagule load of trapped I. mexicanus was 269·5 (± 14·1) in 2004 and 281·7 (± 35·7) in 2005 and was 216·1 (± 28·9) in 2004 and 251·9 (± 28·4) in 2005 for I. plastographus. Mean propagule loads decreased from May to November in all locations for both species. Propagule loads of beetles emerged from infected stems were lower than that of trapped beetles, with means of 89·4 (± 23·2) and 93·0 (± 23·2) for I. mexicanus and I. plastographus, respectively. Thus beetles must acquire fungal propagules from more than one infected host. These results also suggest that higher contamination rates and propagule loads in spring and early summer may indicate a higher risk of pitch canker transmission, relative to late summer or autumn.     

两种分子技术检测松木中松材线虫的效果评价

为更好地解决当前松材线虫Bursaphelenchus xylophilus检测工作中频现的假阴性问题,通过不同分子技术检测效果的比较评价,摸索出了一套可提高松材线虫检测准确性的技术体系。针对早期感病松木的低线虫量,建立了线虫的最大量分离方法和基于rDNA ITS序列的分子检测体系,该体系可高效检测出单条松材线虫,准确率达93.75%。以来自浙江省不同疫区的96份松木样品为检测材料,比较了SCAR标记和ITS序列2种分子检测技术的阳性率。结果显示,通过首次PCR,ITS_Ⅰ和ITS_Ⅱ序列的检测阳性率分别为52.08%和55.21%,SCAR标记的检测阳性率为30.21%;通过第二次或巢式PCR,ITS_Ⅰ和ITS_Ⅱ序列的检测阳性率提高到了97.92%和100.00%,SCAR标记的检测阳性率提高到了59.38%,表明基于ITS序列的检测阳性率明显高于SCAR标记,且通过第二次或巢式PCR方法可进一步提高检测灵敏度,降低假阴性率。因此,通过线虫的最大量分离并基于rDNA ITS序列的分子检测可明显提高检测准确性,更适用于松材线虫的常规检测。