金边卫矛冷驯化期间SOD和POD同工酶及蛋白的研究

采用凝胶电泳技术比较观察了金边卫矛冷驯化期间叶片超氧化物歧化酶（SOD）、过氧化物酶（POD）同工酶谱及总蛋白的动态变化，就其变化规律与抗寒性的关系作了探讨,并首次鉴定了叶片中SOD的类型.结果表明:冷驯化期间叶片SOD同工酶未发生谱带数目的变化，但有谱带的增强表达，其中Cu-ZnSOD的变化较FeSOD明显.POD同工酶不仅有酶带的增强表达，而且有一条新的弱酶带出现.SOD、POD同工酶谱带随着冷驯化时间的延长而增强表达，但到达一个高峰后逐渐回落到接近对照水平.这表明植株在冷驯化期间随着SOD、POD同工酶变化而形成的低温适应机制可能是提高植株抗寒力的一个重要原因.金边卫矛在冷驯化期间诱导出4种分子量分别为18.7、19.5、15.7和18 kD的酸性蛋白，脱锻炼后仍然存在，表达量基本维持在低温处理时的水平，推测它们可能是抗冻蛋白，与冷驯化后金边卫矛在冰冻温度下的抗冻性相关.同时发现，叶片中多种蛋白质的含量与未驯化苗相比都有所增加，其中分子量分别为17.7、15.8 kD的碱性蛋白B和C及分子量为15.5 kD的酸性蛋白D的增强表达趋势较为明显，这3种蛋白在脱锻炼后含量均下降到接近对照水平，推测与植物在低温条件下代谢途径的改变有关.      

根虫瘟霉寄主范围、生物学特性及其应用研究进展

根虫瘟霉是一种重要的昆虫病原真菌,自然界分布广泛,在农林害虫生物防治中具有广阔的应用前景。系统总结了根虫瘟霉的地理分布和寄主范围,对其生物学特性、田间流行及其影响因子进行了详细阐述,并对根虫瘟霉的应用研究现状及制剂研究最新进展进行综述,探讨了根虫瘟霉制剂研究中存在的问题,为虫霉资源的开发和生物防治应用策略的制定提供理论依据。     

环境因子对根虫瘟霉菌株生长的影响

在自然感病的桃蚜虫尸上分离获得一根虫瘟霉(Zoophthoraradicans)菌株(Zryzh),对菜蚜有一定的侵染能力。本文利用室内离体方法对该菌株生物学特性进行了研究,结果表明:Zryzh在固体平板上生长和产孢的最适温度为20℃,当温度高于30℃时产孢量明显降低,而当温度达到35℃时生长与产孢量均受抑制。不同光照和酸碱度的处理对Zryzh菌落生长与产孢有差异,最适的pH范围是7～9,明暗交替(12L:12D)有利于Zryzh的生长与产孢。     

爬行卫矛下胚轴高频离体再生体系的建立(英文)

In this paper,a protocol for efficient shoot regeneration was successfully developed from hypocotyl explants of Euonymus fortunei var.radicans.Some factors that influenced shoot regeneration such as different combinations of plant growth regulators,types of medium and inoculation ways were studied in order to establish an efficient plant regeneration for transformation.The results showed that hypocotyl explants wero horizontally cultured on a basic medium composed of MS medium supplemented with 0.5 mg·L-1 BAP and 0.01 mg·L-1 NAA for induction and development of adventidous shoots.Ninety-four percent of regeneration frequency and 5.1 shoots per explants were obtmned after 30 days of culture.Regenerated shootsproliferated efficiently on a shoot multiplication medium consisting of MS medium containing 1.0 mg·L-1 BAP and 0.1 mg·L-1 NAA.Microshoots were rooted on a rooting medium made up of MS medium enriched with O.5 mg·L-1 IBA and O.5 mg·L-1IAA.After hardening,90% of plants were successfully established under greenhouse conditions.Histological observation revealed that shoot primordium originated from subepidermal cells of hypocotyl explants and directly developed into adventitious shoots without caHus formation.     

爬行卫矛再生体系建立及根癌农杆菌介导的遗传转化

以爬行卫矛(Euonymus fortunci var.radicans)无菌苗下胚轴为外植体,在附加不同浓度植物生长调节剂的MS基础培养基上诱导培养,通过器官直接发生途径获得再生植株.结果表明,0.5 mg/LBAP和0.01 mg/L NAA组合的诱导效果最佳,其不定芽再生率高达92%,外植体平均不定芽数目为4.2个.将含有雪花莲凝集素基因(Galanthus nivalis agglutinin,GNA)的植物表达载体pBCGm导入根癌农杆菌(Agrobacterium tumefaciens)LBA4404,通过农杆菌介导法遗传转化爬行卫矛的下胚轴,经PCR和PCR-Southern检测,GNA基因已整合到转化植株的基因组中.遗传转化过程中,外植体不经预培养,菌液浓度OD=0.6,共培养3 d,有利于获得最高遗传转化效率.     

初始接种量对安徽虫瘟霉液体培养下菌丝生物量的影响

在温度（２０±１）℃和光照１２Ｌ ： １２Ｄ的条件下,用萨氏培养液对安徽虫瘟霉（Ｚｏｏｐｈｏｒａ　ａｎ－ ｈｕｉｅｎｓｉｓ）进行液体振荡培养（１００ ｒ／ｍｉｎ）,考查不同接种量和液培时间对菌丝生物量的影响。结果表明, 将含干菌丝１８． ６ｍｇ／ｍＬ的母液按１％～１５％（Ｖ／Ｖ）的比例接种后培养４８～７２ｈ,９％和１２％接种量处 理能产生２０ ｍｇ／ｍＬ 以上的菌丝生物量,通过拟合逻辑斯蒂生长模型,发现该菌在上述液培条件下的最 大菌丝生物量为２５ ｍｇ／ｍＬ左右。     

广东省桃蚜虫霉目昆虫病原真菌鉴定

从广东省桃蚜(Myz～petsicae)中,采集到两种虫霉目昆虫病原真菌,根据形态学鉴定,分别鉴定为普朗肯虫霉(Entomophthora planchoniana)和安徽虫瘟霉(Zoophthora anhuiensis),并对这两种真菌进行形态特征描述.普朗肯虫霉(E.plan-choniana)和安徽虫瘟霉(Z.anhuiensis)作为菜地桃蚜的虫霉目昆虫病原真菌为广东省首次报道.     

践踏胁迫对4种园林地被植物叶绿素荧光特性的影响

以佛甲草（Sedum lineare）、矮麦冬（Ophiopogon japonicus var. nana）、络石（Trachelospermum jasminoides）、小叶扶芳藤（Euonymus fortunei var. radicans）等4种园林地被植物进行践踏试验,比较分析其植株生长与叶绿素荧光特性。结果显示：除佛甲草外,几种地被植物践踏后的生长势与翌年恢复性均良好;践踏胁迫后4种地被植物的固定荧光（Fo）图像颜色变深,叶绿素含量有所降低,其中尤以佛甲草最为明显;践踏后6周的PSⅡ原初光能转换效率（Fv/Fm）均明显降低。两种藤本地被植物络石和小叶扶芳藤在践踏胁迫后的光化学猝灭系数（qP）和表观光合电子传递速率（ETR）均高于对照,非光化学猝灭系数（NPQ）低于对照;两种草本地被植物矮麦冬和佛甲草与之相反。综合各项指标来看,藤本地被植物的耐践踏性强于草本地被。叶绿素荧光特性可用于评定地被植物的耐践踏性。     

Redvine (Brunnichia ovata) and trumpetcreeper (Campsis radicans) controlled under field conditions by a synergistic interaction of the bioherbicide, Myrothecium verrucaria, with glyphosate

In field experiments conducted near Stoneville, MS, USA, in 2000 and 2001, the bioherbicidal fungus, Myrothecium verrucaria (Alb. & Schwein.) Ditmar: Fr., was tested alone and in combination with a glyphosate ( N -[phosphonomethyl]glycine) product for controlling natural infestations of the invasive vines, redvine ( Brunnichia ovata [Walt.] Shinners) and trumpetcreeper ( Campsis radicans [L.] Seem. ex Bureau). After 12 days, redvine and trumpetcreeper were controlled by 88% and 90%, respectively, through a synergistic interaction between the fungus and the herbicide, glyphosate. The disease symptomatology was characterized by rapid necrosis of the leaf and stem tissues, with mortality occurring within 72 h. Neither glyphosate alone, nor M. verrucaria alone, controlled these weeds at commercially acceptable levels (≥80%). No visual disease or herbicide damage occurred to the soybean in the treated test plots 12 days after planting. These results suggest that some formulations of glyphosate, mixed with M. verrucaria , can effectively control redvine and trumpetcreeper.     

Effects of Cold Acclimation on Several Enzyme Activities in Euonymus radicans ‘Emorald & Gold’and Its Relation to Semi-lethal Temperature

The changes in activities of superoxide dismutase (SOD), peroxidase (POD) and ATPase in the leaves of Euonymus radicans were studied when seedlings were cold-acclimated (at 4 ℃) for 1 week, 2 weeks, 3 weeks and then treated for 1 d under low temperature stress (at 5 ℃). The semi-lethal temperatures of acclimated and unacclimated seedlings were also investigated. The results indicated that the activities of the three enzymes in the leaves of the seedlings treated at 4 ℃ for 1, 2 and 3 weeks were all higher than those of unacclimated seedings (treated at 22 ℃ as controls). The activities of SOD and POD increased continuously with the prolongation of the time of cold acclimation, but stepped up to summits then down to the levels of the controls. The activities of SOD culminated at the first week, and the activities of POD at the second week. When acclimated and unacclimated seedlings were both treated at 5 ℃ for 1 d, the activities of the three enzymes in the leaves of acclimated seedlings were a little lower than those before stress, but higher than those of the controls. Moreover, the decrease rate of enzyme activities was greatly lower than that of the controls. The results showed that cold acclimation could enhance the stability of the three enzymes in the leaves of seedlings under low temperature stress; the semi-lethal temperature was 19.1 ℃ when the seedlings were treated at 4 ℃ for 3 weeks, but it was 5.4 ℃ when the seedlings were treated at 22 ℃. The decline of the semi-lethal temperature caused by the adaptive changes of enzyme activities was one of the foundations of enhancing the cold tolerance.