Comparison of Crinipellis perniciosa isolates from Brazil by ERIC repetitive element sequence-based PCR genomic fingerprinting

Fifty isolates of Crinipellis perniciosa originating from Theobroma cacao , Heteropterys acutifolia and Solanum lycocarpum , from six states within Brazil, were characterized through ERIC-PCR, representing the first application of this method for molecular characterization within C. perniciosa . Phenetic analysis of banding patterns revealed a separation of isolates on the basis of host of origin, with T. cacao -derived isolates showing only a 0·2 similarity level to a cluster comprising the isolates from H. acutifolia and S. lycocarpum . Considerable intraspecific variability was observed within C. perniciosa isolates from T. cacao , with distinct groups observed correlating with geographical origin. Given that a number of isolates from T. cacao from the Amazon region grouped with isolates from Bahia state, this work discusses the possibility that current C. perniciosa populations pathogenic on T. cacao in Bahia originated from the Amazon region, rather than from alternative host plants.     

蘑菇褐腐病菌生物学特性和防治

蘑菇褐腐病菌菌丝生长和分生孢子萌发适宜温度为24～25℃,低至10℃,高达35℃,孢子停止萌发,在35℃和40℃恒温中,分别经5天和1天,菌丝均失去生活力;高湿有利于菌丝生长和孢子萌发,100％相对湿度下分生孢子萌发率最高;菌丝生长和分生孢子萌发最适宜pH值分别为6和6.4,幼嫩蘑菇煮出液最能刺激孢子萌发,该病菌在菇床初侵染源是覆盖了带有病菌的覆盖土,在夏季对覆盖土壤进行日光曝晒4～5天,覆土前7天,用36％～38％化学纯甲醛3.5kg,兑水20～30kg,喷洒于种植111m~2蘑菇的覆盖土中熏蒸48h以上,防病效果均理想;发病后及时挖除病菇,能防止病菌再侵染,减轻褐腐病的为害。     

培养条件对有害疣孢霉生长的影响

为了对双孢蘑菇褐腐病的科学生态防控提供理论依据,测定了4株形态差异较大的有害疣孢霉菌(GS 0036,HN 0015,SD 007,WH 001)在常见蘑菇煎汁培养基、不同光质条件和不同浓度盐溶液条件下的菌丝生长速度、厚垣孢子产生量、分生孢子萌发情况和耐盐性。结果表明:除灵芝煎汁外,6种常见蘑菇煎汁培养基对供试菌株厚垣孢子的产生均优于PDA培养基;不同光质对有害疣孢霉菌影响不同,SD007菌株在红光下菌丝生长速度最快,其他3种菌株均在黑/白交替光质下菌丝生长最快,短波光(蓝光)能抑制有害疣孢霉菌丝的生长及厚垣孢子的产生;4株有害疣孢霉的菌丝生长量和厚垣孢子产生量随着NaCl浓度的升高均明显下降,NaCl溶液对HN 0015抑制效果最明显,当NaCl浓度在24g/L时所有有害疣孢霉菌菌株的分生孢子几乎不萌发。     

毁灭泰泽球虫(Tyzzeria perniciosa)内生发育的超微结构研究 4.大配子发育与卵囊壁形成

毁灭泰泽球虫的大配子是在含有泡内小管的带虫空泡中发育。成囊颗粒Ⅰ在大配子的细胞基质中发育,而成囊颗粒Ⅰ则形成于内质网之嵴内。少数多膜小体见于年轻大配子的细胞质浅层。成熟大配子含有大量的多糖颗粒、少数电子半透明小泡、内质网、线粒体和小管。合子外层膜的膨胀和分离标志着卵囊壁形成的开始。成囊颗粒Ⅰ的物质通过分子渗透过程在合子表面沉积,形成外层。当外层从合子表面分离之后,成囊颗粒Ⅱ的内容物在合子限制膜下累积成层。内层的形成可能是要通过多层物质的分泌与融合的连续过程。粗面内质网在成囊颗粒Ⅱ物质的转运,以及新膜的分离和形成中均起着重要的作用。成熟的卵囊壁由三层组成,分别称为外周膜、外层和内层。     

不同地区有害疣孢霉菌株生物学特性研究

本文于同一条件下对收集于不同地区的18株有害疣孢霉（Mycogone perniciosa）菌株进行生物学特性研究、比较。结果表明,江、浙、沪分离得到的有害疣孢霉菌株在菌落形态。菌丝生长速度、产孢量和致病症状上都与其它地区的有害疣孢霉菌株存在差异。     

Groundnut Rust (Puccinia arachidis) in Brunei

Abstract

A field trial was conducted during the cotton growing seasons of 1978-79 and 1979-80 at Hissar, Haryana (India) to determine the capture threshold of male pink bollworm moths in traps baited with gossyplure for timing the insecticidal application. It was found that application of insecticides when the number of male moths averaged 4 or 8 per trap per night was superior to fixed spray schedule (spraying at an interval of 13-14 days starting from middle of August) in reducing the pink bollworm incidence and obtaining higher yield of seed cotton. For effective and economic control of the pest, insecticides should be applied within 24-48 hours when the number of male moths captured in gossyplure baited traps reaches 8 per trap per night.     

纳他霉素对蘑菇疣孢霉病的防治效果试验

在实验室PDA试验中,纳他霉素3．0mg／L浓度即可抑制蘑菇疣孢霉孢子萌发,9．0mg／L浓度可以完全抑制其接种块萌发,具有较好的防治效果;而在栽培防治试验中,纳他霉素所有试验浓度（最高100mg／L）对蘑菇疣孢霉病均无防治效果。     

Increased frequency of phytosanitary pod removal in cacao (Theobroma cacao) increases yield economically in eastern Peru

Diseases caused by Moniliophthora roreri (moniliasis), Crinipellis perniciosa (witches’ broom) and Phytophthora palmivora (black pod) are the most important factors limiting cocoa production in Peru and cultural management is considered to be the only practical means of control for the smallholder. The objective of this study was to develop an epidemiologically and economically sound control recommendation based on the frequency of phytosanitary pod removal. Weekly removal of diseased pods reduced the incidence of diseases significantly in comparison with fortnightly removal. In three fields, moniliasis was decreased by 26–41%, black pod by 35–66% and witches’ broom on pods by 14–57%. The cumulative effect was a consistent yield increase from an average of 504–660 kg ha⁻¹ yr⁻¹. Returns compensated for increased labour costs. Weekly pod removal was 32% more profitable. Time-course analyses indicated that weekly removal should be practised throughout the year under field conditions of eastern Peru.     

毁灭泰泽球虫内生发育的超微结构研究 Ⅲ.小配子生殖与小配子

毁灭泰泽球虫的小配子生殖发生在小肠上皮细胞内由单层膜围成的带虫空泡中。其细胞核的分裂过程与裂殖生殖时期的相似,但小配子体的细胞核缺少核仁,染色质在核的浅层聚集成致密的斑块。在小配子的形成过程中,核附近的中心粒转变为基粒,其中央微管消失。随后,两根鞭毛从基粒长出,突入带虫空泡。细胞核的致密部分逐渐地进入小配子体的表面突起,并最终发育为小配子的细胞核;而核的疏浅部分则留在小配子体的细胞质中,成为残体的成份。成熟的小配子拥有两根纤长的鞭毛和香蕉形的身体,体内含有长形的细胞核及在其尖端嵌入的线粒体,一组微管(4 1 1)自基粒附近向体后延伸,但仅约3根微管抵达身体的末端。     

两种杀螨剂对害长头螨室内毒力测定

采用室内喷药法测定了联苯肼酯悬浮剂和螺螨酯悬浮剂对为害食用菌的害长头螨(Dolichocybe perniciosa)的毒力。结果表明:不同浓度联苯肼酯和螺螨酯对害长头螨的生长发育均有影响,螺螨酯对害长头螨毒杀效果优于联苯肼酯,二者的致死中浓度分别为38.96mg/L和149.02mg/L,螺螨酯在浓度43.6mg/L时完全抑制害长头螨膨腹繁殖。