四种短命植物若干生物学生态学特性的研究

 卷果涩芥(Malcolmia scorpioides)、四齿芥(Tetracme quadricornis)、长齿四齿芥(T．recurvata)和狭果鹤虱(Lappula semiglabra)为新疆北部常见的四种短命植物。本文从种子生物学、发育节律、株形和植株寿命等方面研究它们与生存环境的协调与适应。     

湖南的新记录植物(四)

报道了湖南植物分布新记录,其中新记录科1个,即无叶莲科Petrosaviaceae;新记录属2个,即无叶莲属Petrosavia Becc.和鸢尾兰属Oberonia Lindl.;新记录种11个,即小药八旦子Corydalis caudata(Lam.) Pers、韫珍金腰Chrysosplenium wuwenchenii Jien、桂林乌桕Sapium chihsinianum S.K.Lee、蛛毛苣苔Paraboea sinensis(Oliv.) Burtt、扁穗牛鞭草Hemarthria compressa(Linn.f.) R.Br.、曲轴黑三棱Sparganium fallax Graebn、无叶莲Petrosavia sakuraii(Makino) J.J.Smith ex Steenis、北重楼Paris verticillata M.-Bieb.、大叶仙茅Curculigo capitulata(Lour.) O.Kuntze、狭叶鸢尾兰Oberonia caulescens Lindl.、无距虾脊兰Calanthe tsoongiana T.Tang et F.T.Wang;新记录变种1个,即峨嵋金腰Chrysosplenium hydrocotylifolium Lévl.et Vant.var.emeiense J.T.Pan。     

21种植物提取物对玉米象的生物活性

为了筛选对粮库安全的植物源杀虫剂,研究了21种植物的4种溶剂（无水乙醇、丙酮、乙酸乙酯和石油醚）提取物对玉米象Sitophilus zeamais Motschulsky的驱避和触杀作用。结果表明,高良姜Alpinia officinarum石油醚提取物、黄姜Curcuma longa丙酮提取物和山鸡椒Litsea cubeba石油醚提取物对玉米象成虫的驱避作用显著,处理60 h平均驱避等级均达到Ⅴ级,平均驱避率分别为80.02%、80.60%和81.70%。在21种植物中,石菖蒲Acorus gramineus和巴豆Croton tiglium的4种溶剂提取物均对玉米象成虫的触杀作用明显,7.86 mg/cm²的剂量处理4天后的校正死亡率均达到90%以上。     

四种植物精油成分对枸杞棉蚜的生物活性

【目的】研究植物精油4种成分丁香酚(eugenol)、α-松油醇(α-terpineol)、肉桂油(cinnamon oil)和香茅油(citronella oil)对枸杞棉蚜Aphis gossypii的生物活性以及马来酸二乙酯和水杨酸乙酯对这些化合物对枸杞棉蚜毒力的影响,为无公害防治枸杞(Lycium spp.)害虫奠定科学基础。【方法】采用二项选择法测定上述4种精油成分(1%)对枸杞棉蚜无翅成蚜的驱避作用;玻璃管药膜法进行生物测定,评估这4种化合物及其与马来酸二乙酯或水杨酸乙酯的混合液对枸杞棉蚜成蚜的毒力;采用生物化学方法分析这些化合物处理后枸杞棉蚜成蚜乙酰胆碱酯酶(AChE)和三磷酸腺苷酶(ATPase)的离体活性。【结果】α-松油醇(1%)对枸杞棉蚜无翅成蚜的驱避作用明显,1, 2和3 h的驱避率分别为58.1%, 58.6%和55.7%; 3 h时测试的4种化合物对枸杞棉蚜成蚜的驱避率由大到小依次为α-松油醇>香茅油>肉桂油>丁香酚。丁香酚对枸杞棉蚜成蚜的毒杀作用最强,处理4 h时的LC₅₀值为0.48 mL/L,肉桂油、α-松油醇、香茅油对枸杞棉蚜成蚜的LC₅₀值分别为1.23, 6.24和11.97 mL/L。对枸杞棉蚜成蚜的生物测定结果表明,马来酸二乙酯对香茅油、肉桂油、丁香酚和α-松油醇的增效比分别为2.75, 2.86, 1.78和1.56;水杨酸乙酯对香茅油、肉桂油、丁香酚和α-松油醇的增效比分别为3.41, 2.67, 2.00和1.89。毒力比结果表明,所测定的4种化合物对枸杞棉蚜的毒力相差49.9倍,丁香酚与马来酸二乙酯或水杨酸乙酯的混合液对枸杞棉蚜的触杀毒力最高。4种精油成分对枸杞棉蚜成蚜AChE和ATPase活性有不同的作用,丁香酚对AChE活性的抑制作用最强,但对ATPase活性表现为低浓度促进,高浓度抑制。【结论】α-松油醇对枸杞棉蚜驱避作用最好;丁香酚、α-松油醇、肉桂油和香茅油这4种精油成分对枸杞棉蚜的毒力相差很大;丁香酚与马来酸二乙酯或水杨酸乙酯混合后对枸杞棉蚜的毒力提高,具有进一步开发应用的潜力;所测精油成分对枸杞棉蚜离体AChE和ATPase活性有一定抑制作用。     

仓贮害虫寄生蜂-雅脊金小蜂及其属内种的识别

雅脊金小蜂Theocolax elegans(Westwood,1874)是一种世界性分布的贮粮害虫寄生蜂,寄主范围广泛。本文对其成虫形态特征进行记述并从形态学、寄主与分布等方面区分了蚁形金小蜂属Theocolax内的近缘种类,并编制该属已知种的检索表。以期为相关鉴定提供参考依据,为雅脊金小蜂天敌利用提供资料。     

一种在豌豆植物中瞬时表达外源蛋白的新方法

以豌豆植物为实验材料建立了一种瞬时表达外源蛋白的新方法-发芽种子真空侵染法。以绿色荧光蛋白作为报告基因对该体系进行优化的结果表明其最佳工作条件为:菌体工作液浓度OD600=1.0~1.5,真空压力0.08 MPa,真空侵染时间1 min。该方法操作简单,可以同时侵染大量的豌豆植物材料,并将实验周期缩短为15 d,植物侵染后12~14 d可收获外源蛋白,外源蛋白表达量与叶片注射法相当,是一种在豌豆植物中批量生产外源蛋白的新方法。     

10种植物乙醇提取物对金银花蚜虫的生物活性研究

采用微量滴定法测定了10种植物乙醇提取物对金银花蚜虫的生物活性.结果表明,10种植物乙醇提取物对金银花蚜虫均有一定的驱避活性和毒杀作用.在10 mg/mL的浓度下,臭椿、曼陀罗和桂花的提取物对金银花蚜虫的驱避作用较强,其在12 h的驱避率分别为78.74％、77.54％、75.11％;夏枯草提取物的驱避效果最弱,12 h的驱避率为58.53％.随着处理时间的延长,各植物提取物的驱避效果均呈下降趋势;印楝提取物的毒杀活性最强,72 h后的校正死亡率达68.30％;曼陀罗和苦瓜的作用次之,72 h后的校正死亡率分别为66.41％和63.70％;夏枯草提取物的作用最低,72 h后的校正死亡率仅为26.47％.进一步的毒力分析表明,印楝提取物对金银花蚜虫的毒力较强,24h的Lc.值为11.0836 mg,/mL.     

八种植物提取物对蔬菜害虫的室内毒力研究

研究了巴豆 (Croton tiglium L.)等八种植物的提取物对几种常见蔬菜害虫的非选择性拒食和毒杀作用。研究结果表明 :巴豆、青蒿、米仔兰等三种植物提取物在 0 .5 %浓度时对菜粉蝶 5龄幼虫的拒食率分别达到96 .36 %、82 .4 2 %和 86 .30 % ,对菜粉蝶 3龄幼虫的毒杀死亡率分别为 5 9.38%、2 8.1 3%和 4 3.75 % ;对黄曲条跳甲成虫的毒杀死亡率为 77.5 0 %、5 6 .2 5 %和 4 8.75 % ;对美洲斑潜蝇幼虫的毒杀死亡率分别为 83.33%、5 6 .6 7%和 73.33%。     

三种植物生长调节剂对降香黄檀种子发芽的影响

采用三种植物生长调节剂GA3、IBA和6-BA不同浓度按正交设计方法,搭配处理组合,对降香黄檀种子进行处理,通过对种子发芽率、发芽势和发芽指数指标的测定,研究不同浓度的植物生长调节剂对珍贵用材树种降香黄檀种子萌发的影响。结果表明:3种植物生长调节剂浸种对降香黄檀种子萌发以6-BA的促进效果较好,GA3次之,而IBA对降香黄檀种子的发芽促进作用不明显,以处理组合6-BA50mg/L6h为最优,显著提高种子的萌发率。     

十四种种子植物环剥再生的初步观察

我国自从发现一些植物环剥后可以成活,再生出新皮以来,几年来已经陆续对有些树木进行了试验。但是,对于环剥后的形态结构变化,除了少数几种树木外,一般都未有系统报道。我们对14种种子植物进行了剥皮试验,发现不同的植物剥皮后的形态结构变化差别很大,再生作用也不尽相同。材料和方法本试验于1984年6—7月在北大校园中进行,选取银杏(Ginkgo biloba L.)、白皮松(Pinus bungeana Zucc.)、苹果(Malus pumila Mill.)、桑树(Morus alba L.)、洋槐     

杂草种子寿命的研究

1976—1978年先后把稗、看麦娘、藜、猪殃殃等24种农田主要杂草种子分别埋入水田和旱田(棉麦)的土壤内,每年挖出一部分种子进行发芽试验,测定其存活率,8年试验结果表明,经4年后稗草种子在水田内还有34.2—52.5%发芽率,至第7年全部死亡;而在旱田内经2年,只有8.7%的发芽率,第三年死亡率达100.0%;看麦娘、硬草、棒头草种子在水田内2年发芽率分别为39.3%,62.7%、33.3%,而在旱田内2年后死亡率达100.0%;猪殃殃、波斯婆婆纳的种子在旱田中2年内的发芽率为57.0%、80.0%,但在水田内其死亡率达98.7%、100.0%;马齿苋的种子在旱田内经7年发芽率为33.3%;而水田内为23.0%。在水、旱不同条件下,不同杂草种子的寿命是不一样的,这将为水旱轮作防除农田杂草提供了理论依据。     

新疆4种锦鸡儿属植物种子生活力和萌发对积雪下埋放的响应

种子贮藏之后的生活力和萌发能力取决于贮藏期间的环境和种子特性。季节性积雪通过补充水源、调节近地表温度、湿度等条件而影响土壤中种子的生活力和萌发能力。本文以新疆野生准噶尔锦鸡儿（Caragana soongorica Grub.）、特克斯锦鸡儿（C. tekesiensis Y. Z. Zhao & D. W. Zhou）、刺叶锦鸡儿（C. acanthophylla Kom.）和荒漠锦鸡儿（C. roborovskyi Kom.）种子为对象,通过模拟积雪覆盖和室内萌发实验,研究了4种植物在雪下贮藏近5个月后种子的生活力和萌发能力。结果显示：与无积雪覆盖相比,积雪覆盖下准噶尔锦鸡儿种子的生活力丧失最多,达36%,刺叶锦鸡儿和荒漠锦鸡儿下降不到3%,特克斯锦鸡儿无明显变化。积雪覆盖下4种锦鸡儿的种子萌发率为37%～84%,与无积雪覆盖的差异不显著。积雪覆盖使刺叶锦鸡儿和荒漠锦鸡儿少部分种子在野外提前萌发。建议刺叶锦鸡儿和荒漠锦鸡儿在初冬下雪前播种,而准噶尔锦鸡儿和特克斯锦鸡儿可于次年春季播种。     

海洋桡足类的热耐受性

为了探明热排放对近海生态的影响,选用我国东海近海主要桡足类,采用热升温实验方法对其半致死温度进行研究.结果表明,不同生物在相同适温条件下和同种生物在不同适温条件下的热耐受能力均存在差异.自然适应水温为13.5 ℃,中华哲水蚤(Calanus sinicus)和细巧华哲水蚤(Sinocalanus tenellus)的24 h半致死温度值分别为26.9 ℃和25.4 ℃;自然适应水温为14.2 ℃,中华异水蚤(Acartiella sinensis)和近缘大眼剑水蚤(Corycaeus affinis)的24 h半致死温度值分别为26.7 ℃和30.5 ℃;自然适应水温为28.0 ℃,背针胸刺水蚤(Centropages dorsispinatus)、强额拟哲水蚤(Paracalanus crassirostris)、刺尾纺锤水蚤(Acartia spinicauda)和尖额真猛水蚤(Euterpina acutifrons)的24 h半致死温度值分别为34.0 ℃、34.3 ℃、35.7 ℃和36.0 ℃.细巧华哲水蚤在自然适应水温分别为13.5 ℃和23.5 ℃下的24 h半致死温度值为25.4 ℃和33.0 ℃.     

外来有害生物风险评估方法研究进展

外来有害生物给生态环境、农业生产、人类健康带来的影响和造成的经济损失越来越受到人们的关注。与此同时,对外来有害生物风险评估方法的研究及其应用也在逐步深入。通过对多指标综合评估法、农业气候相似距法、地理信息系统、生态气候模型评价、模糊综合评判等方法的分析,概述了外来有害生物风险评估方法的含义和利弊,探讨了不同外来物种在不同环境条件下的适生性,综述了国内外评估方法应用的研究进展,对该研究领域的发展趋势进行了展望。     

The impact of flooding and drought on seeds of Cnidium dubium, Gratiola officinalis, and Juncus atratus, three endangered perennial river corridor plants of Central European lowlands

The effects of flooding and drought on the post-flooding survival and germinability of seeds in the soil were investigated for three endangered river corridor angiosperms Cnidium dubium (Schkuhr) Thell., Gratiola officinalis L. and Juncus atratus Krocker. Freshly matured seeds were placed in small nylon bags and were buried in pots filled with soil collected from a wetland along the Lower Havel River. The pots were subjected to different winter/spring flooding treatments (30, 60, 120, and 180 days) and to drought for up to 3 years. Every year in spring, after drawdown, the seeds were exhumed, counted and tested for germination. Seed mortality of flooded seeds was low, except for C. dubium. Flooding did not affect germination of seeds of J. atratus. Flooding of seeds of C. dubium and G. officinalis had inconsistent, but no beneficial effects on germination of either. The year of harvest and the interannual variability of weather are found to be the main factors affecting germinability of C. dubium and G. officinalis in the course of the three consecutive years.The experiment showed that the capacity of the flooded seed bank to maintain germination ability and viability for extended periods of time could be directly related to the flooding duration of natural habitats of the three species. The three species are resilient to variable flooding. Seeds appeared desiccation tolerant, and single flooding events do not deplete their seed bank.     

Seed bank dynamics of two obligate seeders, <Emphasis Type="Italic">Cistus monspeliensis</Emphasis> and <Emphasis Type="Italic">Rosmarinus officinalis</Emphasis>, in relation to time since fire

Many species in Mediterranean-type ecosystems regenerate after fire by seed germination from soil seed banks. Seed bank dynamics of two of those obligate seeders, Cistus monspeliensis and Rosmarinus officinalis, were investigated in relation to stand age since fire in southwestern Portugal. Soil seed density, annual seed input, annual seed losses through germination and seed persistence were compared between species at stands differing in age since fire (5, 10 and 35 years). Soil seed density and seed input increased over the first decade after fire and were lowest at 35-year-old stands for C. monspeliensis. In R. officinalis, few seeds were produced and found in the soil at early stages, and maximum seed input and soil seed density were attained at 35-year-old stands. Soil seed density was mostly driven by seed production in both species, which is largely dependent on plant traits and population dynamics related to fire. Overall, stand age since fire had a negligible effect on seed germination, seed persistence and viability. Ten to 39% of buried seeds were not recovered after 1 year, and viability of seeds recovered was 97–100% for C. monspeliensis and only 0–3% for R. officinalis. Variation in plant traits within the seeder syndrome was evidenced by this study. R. officinalis evidenced lower seed persistence, lower proportion of viable seed produced and lower density of viable soil seed than C. monspeliensis at any stage after fire. R. officinalis is expected to depend largely on previous year seed production for population replacement after fire.     

短时间高温处理对棉蚜存活的影响

为探索棉蚜Aphis gossypii Glover种群动态与高温的关系,研究了不同温度(30、34、38、42、46℃)、不同处理时间(1、2、5、8h)对棉蚜存活的影响。结果表明:在同一处理时间条件下,棉蚜的存活率随着温度的升高而降低;在同一处理温度下,棉蚜的存活率随处理时间的延长而降低。30～38℃温度范围内,棉蚜存活率降低缓慢,从42℃开始棉蚜的存活率迅速降低。棉蚜半数致死温度随着处理时间的延长而降低;相同处理时间条件下,若蚜半数致死温度高于成蚜,若蚜较成蚜更耐高温。     

越冬期间高羊茅叶片和根颈的抗冻性与碳水化合物和脯氨酸含量的关系

随着冬季气温的降低,高羊茅叶片、根颈中可溶性糖类和脯氨酸含量逐渐上升,抗冻性逐渐增强;春季气温逐渐回升时,两者含量则缓慢地减少,抗冻性逐渐减弱.半致死温度(LT50)与总可溶性糖、脯氨酸含量之间呈极显著负相关.     

The effect of deceptive fruits on predispersal seed predation by birds in Pistacia lentiscus

Deceptive fruits (fruits containing empty seeds and seedless fruits) inthe dioecious shrub Pistacia lentiscus L. (Anacardiaceae)remain attached to the plant throughout the dispersal season. This studyaddresses the hypothesis that deceptive fruits may contribute to parentalfitness by reducing predispersal seed predation by granivorous birds becausethese fruits represent handling costs to predators and they prefer to forageselectively on shrubs with filled fruits. This study was run in two populationsof P. lentiscus and finds that deceptive fruits reduceseedpredation by granivorous birds but only in the population that presented higherP. lentiscus female density, and a higher variability inthe percentage of deceptive fruits among P. lentiscusfemales. Under this scenario, the benefits of flying to another female might behigher than those of remaining in the same female searching filled seeds. Bycontrast, the costs of flying to other females, when they are scarce and have asimilar percentage of deceptive fruits may be higher than the benefits.     

东北刺人参种子萌发影响因子的研究

东北刺人参(Oplopanax elatus Nakai)种子透水性良好,休眠后萌发不受其影响.种皮和胚乳的水提取物中存在萌发抑制物质,胚乳中提取物对白菜种子萌发的抑制效果比种皮更明显.种子自然脱落时胚尚未分化完全,处于心形胚阶段.种子需要先温暖层积以完成胚的分化与生长,然后转入低温层积完成生理后熟.同批种子胚的发育不完全同步,变温层积处理7个月有极少数种子萌发,连续变温层积处理17个月大部分种子萌发.不同年份受气候条件影响,种子产量和发芽率差异较大.种子耐贮性较强,贮藏2年的种子生活力变化不大,仍具有较高的萌发潜力.