美国梧桐嫩枝扦插生根试验

对植物生长调节剂、扦插基质、插穗粗度等影响美国梧桐嫩枝扦插生根效果的因子进行了试验。结果表明,在全光照自动间歇喷雾条件下,美国梧桐嫩枝插条生根率及根系生长因植物生长调节剂的种类、质量浓度和处理时间、基质的组分及插穗粗度的不同有明显差异。在6～8月,筛选0.6～0.7 cm粗度插条,使用50 mg/L NAA与50 mg/L IBA的混合液浸泡处理1 h后,扦插于等体积的沙+砻糠灰+珍珠岩=混合基质中,60 d成活率可达95.5%。     

一球悬铃木优良家系的评选

对1999年引自美国的12个种源47个一球悬铃木半同胞家系子代进行了综合评定,在5个试验点分别筛选出了适应性强的优良家系.虽然对4、5年生的一球悬铃木进行选择的结果不尽相同,但诸如松江点的10、16,镇江点29、36等5个试验点的21个优良家系表现是相对稳定的,而14和36号家系则适应范围更广.5个试验点的优良家系多来...     

对西花蓟马高效金龟子绿僵菌菌株筛选及在花生田间的应用效果

西花蓟马Frankliniella occidentalis是一种世界性检疫害虫，对包括花生在内的农作物造成极大威胁，金龟子绿僵菌在西花蓟马生物防治中可发挥重要作用。本文从23株金龟子绿僵菌中筛选出菌株M18-8-4，经紫外诱变得到F1、F2代菌株，测定了其及两代诱变菌株对西花蓟马的室内毒力，并对筛选到的高毒力菌株进行田间药效试验。室内毒力测定结果显示，在相同浓度孢子菌悬液下，诱变菌株F2-M18-8-4对西花蓟马的毒力最强，致死中时为2.13 d。以西花蓟马的校正虫口减退率、花生校正保叶效果和增产效果评价了金龟子绿僵菌F2-M18-8-4和3种化学农药（吡虫啉、噻虫嗪、乙基多杀菌素）对西花蓟马的田间防治效果。施药7 d、10 d后，金龟子绿僵菌F2-M18-8-4与3种化学农药对西花蓟马校正虫口减退率无差异；施药15 d后，金龟子绿僵菌F2-M18-8-4对西花蓟马的校正虫口减退率显著高于这3种化学农药，达79.52%，花生校正保叶效果最高，达63.58%，其次为乙基多杀菌素58.11%。在增产效果上，金龟子绿僵菌F2-M18-8-4防治西花蓟马对花生增产效果最好，达9.09%；其次为乙基多杀菌素7.40%。本研究结果表明筛选高毒力金龟子绿僵菌菌株，在适合的时机防治西花蓟马，可部分替代化学农药，并发挥良好的防治效果。     

北美香柏引种育苗试验初报

从美国引进6个不同种源地的北美香柏种子,选用先进的穴盘育苗技术,在上海地区进行种源、播种时期和覆盖材料等对比试验。试验结果表明:不同种源地的种子在发芽率方面,出苗始期的发芽率差异不显著,但后期出苗率有显著差异;不同种源幼苗生长高度在出苗始期等各阶段的差异均不显著。种子、种苗受覆盖材料和温度的影响较大。定植后高生长缓慢,有待进一步观察。     

西花蓟马对非嗜食寄主蚕豆植株短期适应的生化机制

为明确西花蓟马Frankliniella occidentalis对非嗜食寄主蚕豆植株短期适应的生化机制,将菜豆豆荚上长期饲养的西花蓟马转移至蚕豆植株上胁迫饲喂,分别在12、24、48、72和96 h测定西花蓟马体内解毒酶、保护酶、消化酶的活性及营养物质的含量。结果表明,取食蚕豆植株后西花蓟马体内羧酸酯酶（carboxylesterase,CarE）活性不断升高,在72 h时达到最高值0.65 U/mg prot,然后下降;谷胱甘肽-S-转移酶（glutathione-S-transferase,GST）活性也显著增加,且随取食时间延长一直升高,在96 h时达到最高值18.85 U/mg prot;细胞色素P450(cytochrome P450,CYP450)活性在12 h受到显著抑制,降至0.02 U/mg prot,仅为对照的76.89%,随时间推移,在72 h时达到最高值并显著高于对照。过氧化氢酶（catalase,CAT）、过氧化物酶（peroxidase,POD）和超氧化物歧化酶（superoxide dismutase,SOD）活性均先升高后降低,在48 h时酶活性达到最...     

Toxicity of biocide GCSC-BtA on arthropod pests under different temperature conditions

The present research dealt with the toxicity of GCSC-BtA (Germany–China Scientific Cooperation-Bacillus thuringiensis-Abamectin), a new type biocide developed by conjugating a toxin from Bacillus thuringiensis (B.t.) with Abamectin from Streptomyces avermitilis, on arthropod pests under different temperature conditions. The results showed that GCSC-BtA possessed higher toxicity than B.t. crystal, Abamectin or Cypermethrin, with pest mortalities of 97.9, 93.7, 96.4, 82.3 and 96.7% for Tetranychus cinnabarinus (Boisd.) (Acari, Tetranychidae), Frankliniella occidentalis Pergande (Thys., Thripidae), Aphis fabae Scopoli (Hom., Aphididae), Plutella xylostella (L.) (Lep., Plutellidae) and Cameraria ohridella Deschka et Dimić (Lep., Gracillariidae), respectively. Toxicities of GCSC-BtA to T. cinnabarinus and P. xylostella decreased significantly at the older developmental stage with an exception that egg stage had the highest tolerance, in which LC₅₀s of GCSC-BtA were 0.0001, 0.0019 and 0.0708 mg/ml for nymph, adult and egg of T. cinnabarinus, and that 0.0399, 0.2035 and 0.9033 mg/ml for the 2nd instar larvae, 4th instar larvae and egg of P. xylostella, respectively. Also, the biocide was more effective to the lower stage of A. fabae than the higher one with LC₅₀s of 0.0023, 0.0086 and 0.0171 mg/ml against 1st instar nymph, 3rd instar nymph and adult, respectively. In general, toxicity of the new type of biocide was positively related to temperature against all the tested pests, except against T. cinnabarinus, where it was almost similar at the three temperature conditions. GCSC-BtA displayed significantly lower toxicities at 15/20°C than 20/25°C or 25/30°C against F. occidentalis, A. fabae, P. xylostella and C. ohridella. However, no significant difference was found in the toxicities against F. occidentalis, A. fabae and C. ohridella above 20°C, whereas toxicity against P. xylostella increased as temperature raised. Therefore, to achieve higher efficacy in the field, application rate and time should be devised according to these factors.     

Ornamental plants and thrips populations associated with tomato spotted wilt virus in Greece

A survey was conducted in order to record the ornamental plants that are hosts of tomato spotted wilt virus (TSWV) and impatiens necrotic spot virus (INSV) in Greece. Polyclonal antibodies prepared against the N protein of a Greek isolate of TSWV fromGerbera jamesonii (GR-34) were used. Leaf samples were taken from plants showing typical symptoms of tospovirus infection such as chlorotic and necrotic rings on the leaves and malformation and necrosis of the flowers. The samples were tested by double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) using polyclonal antibodies to the N proteins of TSWV and INSV (NL-07). ELIS A-positive samples were mechanically transmitted to plants ofPetunia hybrida, Nicotiana rustica andN. benthamiana to confirm infection. Although none of the samples was found infected with INSV, TSWV presence was recorded in 42 botanical species that belong to 40 genera in 27 families. Among them the speciesBeloperone guttata, Coleus barbatus, Impatiens petersiana andLilium auratum are reported for the first time as hosts of TSWV, whereasBegonia sp.,Catharanthus roseus Celosia cristata, Dianthus chinensis, Fuchsia hybrida andStephanotis floribunda are found as new hosts of the virus in Greece. Thrips collected from TSWV-infected plants were in most cases identified asFrankliniella occidentalis, except from plants ofDendranthema sp. andDianthus caryophyllus whereThrips tabaci individuals were also identified. Different percentages of transmitters were noticed when the thrips populations collected from TSWV-infected ornamental hosts were tested for transmission of TSWV.     

北美悬铃木无性系生根特性遗传变异研究

对50个从北美悬铃木优良家系中初选的无性系进行扦插生根性状研究.结果表明:无性系问的扦插成活率、扦插生根时间、生根根数、根系总长度等性状在基质盆插和圃地扦插均达到极显著差异水平.无性系扦插生根性状的重复力介于0.219 7-0.592 3之间,表明这些性状受中等程度的遗传控制.北美悬铃木扦插生根能力差异极大.发现NY36、NY44、SX1、ZJ9、SJ36、SX11、ZJ36、DY6、ZJ29、DY36、DY10、SX36、ZJ14、SJ8等生根数量多、重复力高的无性系14个.     

西花蓟马对不同蔬菜寄主的选择性研究

采用植株自由选择法和叶碟法研究了西花蓟马对不同蔬菜寄主及同一寄主不同部位叶片的选择性。结果表明, 西花蓟马成虫对7 种不同蔬菜寄主的选择趋性为西葫芦>茄子砧木>黄瓜>茄子>菜豆>辣椒>番茄,产卵选择性为西葫芦>茄子>菜豆>黄瓜>辣椒>茄子砧木=番茄。西花蓟马喜欢在辣椒、茄子和西葫芦相对幼嫩的上中部叶片产卵, 喜欢在番茄叶片中下部成熟叶片产卵, 而其在菜豆中部叶片的产卵量明显高于上部嫩叶和下部老叶。西花蓟马成虫在辣椒、茄子和菜豆上倾向于在嫩叶取食, 在番茄上喜欢在中下部叶片取食, 在西葫芦的中部叶片发现较多的西花蓟马成虫。