前裂长管茧蜂对桔小实蝇的寄生效能研究

通过组建前裂长管茧蜂的实验种群生殖力生命表,结果表明,前裂长管茧蜂羽化后有1～3 d不等的产卵前期,生殖活动的高峰期出现在羽化后的4～10 d,单日寄生桔小实蝇幼虫量不超过20头,平均每头雌蜂约能繁育125个后代.种群中以雌性个体为主;雌雄比例接近2:1.世代净增殖力和内禀增长率分别为44.44和0.158 1.田间放蜂试验结果表明,当按1:1、1:5及1:10的蜂虫比释放时,15 d后的寄生率分别为36.01%、12.50%和5.18%,但随后寄生率急剧下降.     

日本食蚧蚜小蜂的寄生行为观察

日本食蚧蚜小蜂Coccophagus japonicus Compere是橡副珠蜡蚧Parasaissetia nigra Nietner的重要天敌之一。为了明确该蜂的寄生行为及雌蜂体型大小对其产卵的影响,在室内观察其寄生行为及雌蜂不同体型大小条件下的产卵情况。结果表明：日本食蚧蚜小蜂的寄生过程包括搜寻寄主、识别寄主、产卵器刺探、产卵、产卵后处理5个阶段。日本食蚧蚜小蜂的寄生时间、寄生率、平均着卵量随寄生次数增多而增加,寄生次数与卵量吻合率随寄生次数增加而降低;第1次寄生时,寄生所需时间为19.75 s,寄生率为73.12%,寄生次数与卵量吻合率为69.89%,平均着卵量为0.76粒;第3次寄生时,寄生所需时间为24.37 s,寄生率为83.33%,寄生次数与卵量吻合率仅为8.33%,平均着卵量为1.67粒。雌蜂体型大小与其产卵量呈正相关,体长小于等于1.20 mm时,产卵量及寄生率最小,分别为16.83粒和49.4%;1.40 mm<体长≤1.50 mm时产卵量为33.06粒,寄生率72.3%;而体长大于1.50 mm时产卵量达37.5粒,寄生率为72.2%;雌蜂后足胫节长对其产卵及寄生率也有类似影响,说明该蜂扩繁时应选用体型较大的雌蜂。     

Genetics of Resistance in Vicia sativa L. to Orobanche crenata Forsk.

The genetics of resistance of common vetch (Vicia sativa L.) to broomrape (Orobanche crenata Forsk.) was studied for two years by using the P₁, P₂, F₁, BC¹, BC₂, F₂ F₃, and F₄ generations obtained from crosses between resistant and susceptible lines. Resistant lines were selected by screening a world collection m a naturally infested plot. Resistance was tested both under field and greenhouse conditions. The best index to measure resistance was the number of emerged broomrapes per host plant. The results fit the additive-dominance model. The main component of the variation was additivity; dominance and interaction effects seemed to depend on the environment. When dominance is expressed, a low number is dominant over a high number of broomrapes per host plant.     

中国小麦条锈菌主要流行菌系的寄生适合度研究

 为了预测我国未来小麦条锈菌的优势种群,本研究采用抗性组分法测定了我国条锈菌主要流行菌系的寄生适合度。结果表明:决定我国小麦条锈菌最重要的寄生适合度属性为条锈菌的产孢能力(繁殖力),其次为条锈菌的侵染能力,再次为扩展能力;建立了小麦条锈菌寄生适合度属性3个主成份的数学模型;在供试的菌系中,Su11-4、Su11-14和CY32相对寄生适合度较高,已经成为我国目前小麦条锈菌的优势小种(类型);CY31由于其寄生适合度较低,出现频率逐年下降,已成为次要小种,感染"中四"苗期的新菌系T4类型,由于其寄生适合度低,也不会成为今后一个时期的流行小种。     

白生盘蚧Crescoccus candidus Wang研究初报

生盘蚧属Crescoccus白生盘蚧Crescoccus candidus系王子清1977年采自云南大理,并于1982年建立生盘蚧属(新属),白生盘蚧(新种)。其副模系作者于1979年采自云南丽江。1983年至1986年以昆明温泉羊角村为基点,对其生物学习性及综合治理进行研究。该虫主要为害板栗Castanea mollissima、青冈Cyclobalanpsis glauca、麻栎Quercus acutissima,亦可为害苹果;是板栗树的主要害虫。在昆明地区一年一代,以雌成虫在被害枝条上越冬。雌虫产卵高峰期为6月中旬,初孵若虫涌散峰期为6月中旬,1龄若虫峰期为7月中旬,2龄若虫峰期为9月中下旬,雄虫羽化峰期为10月中旬,6月中旬,10月中旬是化学药剂防治初孵若虫及雄虫的有利时机。生命表资料表明各种自然因子致死率达97.8％,因此加强抚育管理,保护利用天敌,适期使用化学农药是治理白生盘蚧的主要措施。雨水冲刷,二种跳小蜂,长尾小蜂,瓢虫等是控制白生盘蚧种群数量的关键因子;每10cm~2有虫19头可定为防治阈值。     

被子植物叶片气孔制片方法研究

通过叶片气孔制片方法可研究植物有机体的生理代谢和生理功能,总结了常用的气孔制片方法,以为不同叶片材料和不同观察要求下选用合适的制片方法提供参考依据。     

The sea louse Lepeophtheirus acutus (Caligidae, Siphonostomatoida, Copepoda) as a pathogen of aquarium-held elasmobranchs

Lepeophtheirus acutus Heegaard, 1943 (Caligidae, Siphonostomatoida, Copepoda), was collected from or observed on four of six elasmobranch species held at Burgers’ Zoo (Arnhem, The Netherlands). Circumstantial evidence suggested that a zebra shark, Stegostoma fasciatum (Hermann), from the wild carried the infection into the facility, where copepods reproduced and colonized additional hosts. Copepods typically attached on and about the eyes, in the mouth and occasionally about the cloaca and on the claspers. Severe ocular lesions were associated with infections on zebra sharks, a grey reef shark, Carcharhinus amblyrhynchos (Bleeker), whitetip reef sharks, Triaenodon obesus (Rüppell), and giant shovelnose ray, Rhinobatos typus Bennett, while blacktip reef sharks, Carcharhinus melanopterus (Quoy & Gaimard), and blacktip sharks, Carcharhinus limbatus (Valenciennes), living in infested aquaria showed no sign of infection. Water treatments using trichlorfon were considered primarily responsible for the eradication of copepods from hosts and infested aquaria. This case is the first report of a copepod infection being closely associated with disease and death of an aquarium‐held elasmobranch. Given its ability to infect a wide variety of elasmobranchs and promote life‐threatening lesions on some hosts, L. acutus should be considered a dangerous pathogen of captive elasmobranchs.     

小麦条锈病菌新菌系G22-9(CYR34)和G22-14流行趋势预测

为预测小麦条锈病菌新菌系G22-9(CYR34)和G22-14的未来流行趋势,科学指导小麦抗病育种及条锈病治理,采用常规鉴定法于2009—2016年对甘肃省2 330份小麦条锈病菌标样进行了生理小种鉴定及消长动态监测,并对G22-9(CYR34)和G22-14的致病性及寄生适合度进行了测定。结果发现:新菌系G22-9(CYR34)和G22-14在甘肃省的出现频率加快,已从2009年的0分别上升到2016年的34.85%和6.43%,其中G22-9(CYR34)已发展为甘肃省第1位流行生理小种。与主流生理小种CYR32和CYR33相比较,G22-9(CYR34)和G22-14具有毒性谱宽、致病力强、寄生适合度高、哺育品种多等特点。建议在甘肃省特别是小麦条锈病常发易变区的陇南麦区,针对新菌系的出现,及时调整小麦品种布局及育种目标,以持续控制条锈病的发生流行。     

茶蛀梗虫幼虫寄生性昆虫的调查

茶蛀梗虫Casmara patrona Mey rick是湖南茶树的一种重要害虫。已发现有4种天敌昆虫可寄生其幼虫,其学名是:Psen pulcherrimus,Bracon sp.,Macrocentrus sp.和Eriborus tere-brans (Gravenhorst)。前2种是中国新记载种,后2种是中国新寄主记录种。本文叙述了它们的形态特征、生活习性和采集地或分布。Eriborus terebrans是湖南茶园寄生茶蛀梗虫幼虫的优势种类,在长沙它的自然寄生率可达11%。Psen pulcherrimus是次优的寄生蜂,其自然寄生率稍低于前者。