抗棕榈腐烂病菌的杀菌剂和植物浸提物筛选

宛氏拟青霉Paecilomyces varioti是引起棕榈Trachycarpus fortunei腐烂病的病原真菌,用杀菌剂对宛氏拟青霉抑菌试验的结果表明:25％咪鲜胺水乳剂、50％多菌灵可湿性粉剂、80％代森锰锌可湿性粉剂、12.5％腈菌唑乳油、20％嘧霉胺可湿性粉剂对病菌的菌丝生长和孢子萌发都有较好的抑制作用.抑制菌丝生长和抑制孢子萌发的EC50最低的是12.5％腈菌唑乳油,分别为0.1819,0.5406 mg/L,最高的是80％代森锰锌可湿性粉剂,分别为6.6600,5.9502 mg/L.植物浸提物对宛氏拟青霉的抑菌试验表明:在31种植物浸提物中只有南天竹Nandina domestica根、小檗Berberis thunbergii根、苦参Sophora flavescens、草决明Catsia tora果实的浸提物对病菌有较好的抑菌效果,抑菌圈直径在1.02～1.93 cm之间.     

杀菌剂对东北红豆杉立枯病的室内毒力研究

红豆杉属于珍稀濒危植物,在栽培过程中易受到病害的侵袭,为了筛选不同杀菌剂对红豆杉立枯病菌—茄腐皮镰孢菌的毒力作用和防治效果,在室内采用生长速率法进行了6种杀菌剂对红豆杉立枯病菌的室内毒力测定,结果表明,6种杀菌剂的毒力效果分别为:代森锰锌可湿性粉剂菌必治可湿性粉剂70%甲基硫菌灵可湿性粉剂80%代森锌可湿性粉剂50%多菌灵可湿性粉剂75%百菌清可湿性粉剂。代森锰锌对红豆杉立枯病菌的抑菌率最高,毒力作用最强,EC50值为0.32 mg·L~(-1)。     

七种药剂对枣缩果病病原菌-细交链孢菌抑制作用

为有效防治枣缩果病的危害,选用7种杀菌剂对病原菌——细交链孢菌Alternaria alternata进行了室内抑菌试验和田间药剂防治试验。结果表明:20.67%万兴乳油 68.75%易保可分散粒剂 72%链霉素可溶性粉剂、10%世高可分散粒剂 90%新植霉素可溶性粉剂组合、80%大生M-45可湿性粉剂的抑菌能力最强;其次为20.67%万兴乳油、10%世高可分散粒剂和85%枣病克星可湿性粉剂;4%绿盾农抗120水剂对两种病原菌的抑制作用不明显。     

加拿利海枣和丝葵萎缩病的病原鉴定

加拿利海枣和丝葵萎缩病发生于厦门的行道树和苗圃 ,病树基部的茎干内变黑腐烂 ;从发病部位分离纯化获得根串珠霉。将此菌回接于苗圃和盆栽的加拿利海枣 ,产生相同症状并重新分离到该病原真菌。因此 ,通过柯赫法则证实该病的病原物为根串珠霉 ,本文对病害症状和病原形态特征进行了描述。     

7种杀菌剂对杨树烂皮病、溃疡病病菌的室内毒力测定

室内测定了7种杀菌剂对杨树烂皮病病原菌金黄壳囊孢菌Cytospora chrysosperma (Pers.)Fr.、溃疡病病原菌Dothiorella gregaria Sacc.的毒力.72 h含药平板对抑制金黄壳囊孢菌的菌丝生长毒力最强的有10％苯醚甲环唑水分散剂、250 g/L嘧菌酯悬浮剂,EC50值依次为0.0006,0.020 2μg/mL;其次为70％甲基托布津可湿性粉剂,EC50为0.195 8μg/mL;最弱的是树乐粉剂,EC50为319.658 0μg/mL.48 h对杨树溃疡病病原菌的毒力最强的有250 g/L嘧菌酯悬浮剂、10％苯醚甲环唑水分散剂,EC50依次为0.072 2,0.090 4μg/mL;其次为70％甲基托布津和50％多菌灵可湿性粉剂,EC50依次为2.5603,19.0454 μg/mL;树乐最弱,EC50为366.415 7μg/mL.同一药剂对杨树烂皮病菌的毒力强于溃疡病菌.     

杨树烂皮病药剂筛选及防治技术

对杨树烂皮病的化学防治药剂进行筛选结果表明，可杀得（53．8％干悬浮剂）、甲基硫菌灵（50％可湿性粉剂）、双效灵（10％）有明显的抑菌效果；可杀得（53．8％干悬浮剂）、甲基硫菌灵（50％可湿性粉剂）、双效灵（10％）3种药剂毒力线的回归关系显著。对8种杀菌剂进行杨树烂皮病防治试验的结果表明，可杀得等杀菌剂防治效果达90％，药效显著。     

华南滨海区道路绿化中加拿利海枣的移栽技术研究

指出了加拿利海枣作为一种名贵的观赏乔木,越来越被广泛地运用到城市绿化当中。以加拿利海枣在华南滨海地区的移栽为例,探讨了加拿利海枣移植过程中的起苗、种植材料、地下土壤环境、养护管理等方面的技术要点。     

黄帝陵侧柏叶枯病田间防治试验

黄帝陵侧柏叶枯病(Alternaria sp.Pestalotiopsis sp.)发生严重,作者应用80%戊唑醇可湿性粉剂、25%咪鲜胺水乳剂、45%戊唑醇·咪鲜胺水乳剂和75%肟菌·戊唑醇水分散粒剂4种杀菌剂对侧柏叶枯病进行了田间防治试验,并评价80%戊唑醇可湿性粉剂田间大面积防治效果。结果表明:4种供试药剂均对侧柏叶枯病具有一定的防效,其中45%戊唑醇·咪鲜胺水乳剂防治效果最好,第四次施药后10 d在两块试验地防治效果分别为80.35%、84.03%;其次为75%肟菌·戊唑醇水分散粒剂、80%戊唑醇可湿性粉剂、25%咪鲜胺水乳剂。利用80%戊唑醇可湿性粉剂对园区大面积防治试验表明:对侧柏幼林叶枯病的防治效果最好,防效达到了75.49%。通过田间试验得出结论,上述4种药剂可作为田间防治侧柏叶枯病的推荐药剂。     

4种药剂防治美国山核桃黑斑病林间药效试验

为有效防治美国山核桃黑斑病的发生,2017年在浙江省建德市美国山核桃Carya illinoensis林病害始发期和盛发期通过林间试验比较了75%肟菌·戊唑醇水分散粒剂4 000倍液、苯甲·嘧菌脂悬浮剂1 500倍液、苯甲·丙环唑乳油2000倍液、80%代森锰锌可湿性粉剂400倍液4种不同杀菌剂对美国山核桃黑斑病病原菌小孢拟盘多毛孢Pestalotiopsis microspore的防治试验。结果表明:除80%代森锰锌可湿性粉剂(保护性杀菌剂)400倍液防治效果略差外,其他3种杀菌剂(治疗性杀菌剂)对美国山核桃叶片和果实黑斑病均有较好的防治效果,落叶期推迟时间和产量增量均显著高于对照组。其中施用75%肟菌·戊唑醇水分散粒剂4 000倍液对美国山核桃病叶、病果防治效果最好,分别为97.06%和98.16%;落叶期推迟时间最长,比对照推迟98 d;产量增加最大,为对照的362.86%;其次为苯甲·嘧菌脂悬浮剂1 500倍液。研究结果表明,75%肟菌·戊唑醇水分散粒剂4 000倍液、苯甲·嘧菌脂悬浮剂1 500倍液、苯甲·丙环唑乳油2 000倍液3种治疗性防治药剂能有效防治美国山核桃黑斑病。     

10种杀菌剂对橡胶树嘴突凸脐蠕孢菌的室内毒力测定

采用菌丝生长速率法测定10种杀菌剂对橡胶树嘴突凸脐蠕孢叶斑病菌的抑菌能力,结果表明各杀菌剂对嘴突凸脐蠕孢菌的毒力差异显著,苯醚甲环唑、丙环唑、咪鲜胺、异菌脲对橡胶树叶斑病菌的毒力较强,EC50范围在0.0133～0.5572μg/mL,其中苯醚甲环唑、丙环唑对橡胶树叶斑病菌的抑制效果最佳,EC50均小于0.1μg/mL;代森锰锌、百菌清、三唑酮的抑制效果较差,EC50为1～100μg/mL;而多菌灵、甲基硫菌灵、嘧菌酯对嘴突凸脐蠕孢叶斑病菌基本无效。     

几种杀虫剂对吐伦褐球蚧毒力测定

应用7种杀虫剂对吐伦褐球蚧初孵若虫进行室内毒力测定,结果表明:供试杀虫剂对吐伦褐球蚧初孵若虫的毒力大小依次为:1.8%阿维菌素乳油>3%啶虫咪乳油>25%噻嗪酮·异丙威可湿性粉剂>3.6%吡虫啉·高效氯氰菊酯乳油>10%吡虫啉可湿性粉剂>31%杀扑噻乳油>95%机油乳剂。     

Effects of water stress on growth,dry matter allocation and water-use efficiency of a leguminous species, <Emphasis Type="Italic">Sophora davidii</Emphasis>

The adaptation responses to different water conditions and the drought tolerance of Sophora davidii seedlings were assessed in a greenhouse experiment. Two-month-old seedlings were subjected to the following water supplies for 95 days: 100, 80, 60, 40 and 20% of field water capacity. The seedlings at 100% FC had the greatest productivity, height, basal diameter, branch number, leaf number and leaf area. Water supply <80% FC was the threshold of drought-initiated negative effects on seedling growth, yield and physiological processes; these parameters were severely reduced at 20% FC, however, there was no plant death during the experiment. Moreover, water stress decreased leaf relative water content, specific leaf area, leaf area ratio, and water-use efficiency (WUE), whereas it increased the biomass allocation to roots, which resulted in a higher root:stem mass ratio under drought. The S. davidii seedlings tolerated drought by maintaining high leaf relative water content and by reducing branching and leaf expansion. However, low productivity and WUE at 20% FC suggested that seedlings did not produce high biomass under severe drought. Therefore, prior to introducing S. davidii in forestation efforts, a water supply >40% FC is recommended for seedlings to maintain growth and productivity. These results provide insights into limitations and opportunities for establishment of S. davidii in arid regions.     

Influence of irradiance on photosynthesis, morphology and growth of mangosteen (Garcinia mangostana L.) seedlings

The influence of shading intensity on growth, morphology and leaf gas exchange of mangosteen (Garcinia mangostana L.) seedlings was investigated over a 2-year period. Diurnal gas exchange studies revealed significantly higher carbon gain for leaves grown in 20 or 50% shade compared to leaves grown in 80% shade. Seedlings grown in 20 or 50% shade accumulated significantly more dry weight than seedlings grown in 80% shade during the 2-year study period. Seedlings grown in decreased shade showed decreased leaf size, increased leaf thickness, lower specific leaf area (SLA) and higher stomatal frequency. Less shaded seedlings also allocated relatively more dry matter to roots than shaded seedlings and exhibited a significant reduction in leaf area relative to total plant dry weight (leaf area ratio). Increased leaf number, enhanced branching and shorter internodes resulted in a more compact appearance of less shaded seedlings. Irrespective of light conditions, mangosteen seedlings exhibited inherently slow growth because of low photosynthetic rates per unit leaf area, low SLA, low leaf area ratios and inefficient root systems.     

Growth,biomass partitioning,and water-use efficiency of a leguminous shrub (<Emphasis Type="Italic">Bauhinia faberi</Emphasis> var. <Emphasis Type="Italic">microphylla</Emphasis>) in response to various water availabilities

Responses of the endemic leguminous shrub Bauhinia faberi var. microphylla, to various soil water supply regimes were studied in order to assess water stress tolerance of seedlings. Two-month-old seedlings were grown under water supply regimes of 100, 80, 60, 40, and 20% water field capacity (FC), respectively, in a temperature and light-controlled greenhouse. Plant height and leaf number were measured monthly over a 4-month period, while water use (WU), water-use efficiency (WUE), leaf relative water content (RWC), biomass production and its partitioning were recorded at the end of the experiment. Seedlings exhibited the greatest biomass production, height, basal diameter, branch number, leaf number, and leaf area when soil content was at 100% FC, and slightly declined at 80% FC. These parameters declined significantly under 60% FC water supply, and severely reduced under 40 and 20% FC. RWC, WU and WUE decreased, while the ratio of root mass to stem mass (R:S) increased in response to decreasing water supply. Water stress caused leaf shedding, but not plant death. The results demonstrated that B. faberi var. microphylla seedlings could tolerate drought by reducing branching and leaf area while maintaining a high R:S ratio. However, low dry mass and WUE at 40 and 20% FC suggested that the seedlings did not produce significant biomass under prolonged severe water deficit. Therefore, before introducing B. faberi var. microphylla in vegetation restoration efforts, water supply above 40% FC is recommended for seedlings to maintain growth.     

The diversification of terpene emissions in Mediterranean oaks: lessons from a study of Quercus suber, Quercus canariensis and its hybrid Quercus afares

Interspecific gene flow is common in oaks. In the Mediterranean, this process produced geographical differentiations and new species, which may have contributed to the diversification of the production of volatile terpenes in the oak species of this region. The endemic North African deciduous oak Quercus afares (Pomel) is considered to be a stabilized hybrid between the evergreen Quercus suber (L.) and the deciduous Quercus canariensis (Willd.), presumably being monoterpene and isoprene emitters, respectively. In a common garden experiment, we examined the terpene emission capacities, terpene synthase (TPS) activities and nuclear genetic markers in 52 trees of these three oak species. All but one of the Q. suber and Q. canariensis trees were found to be genetically pure, whereas most Q. afares trees possessed a mixed genotype with a predominance of Q. suber alleles. Analysis of the foliar terpene emissions and TPS activities revealed that all the Q. canariensis trees strongly produced isoprene while all the Q. suber trees were strong monoterpene producers. Quercus afares trees produced monoterpenes as well but at more variable and significantly lower rates, and with a monoterpene pattern different than that observed in Q. suber. Among 17 individuals tested, one Q. afares tree emitted only an insignificant amount of terpenes. No mixed isoprene/monoterpene emitter was detected. Our results suggest that the capacity and pattern of volatile terpene production in Algerian Q. afares populations have strongly diverged from those of its parental species and became quantitatively and qualitatively reduced, including the complete suppression of isoprene production.     

Long term losses caused by foliar diseases on growth and survival of Eucalyptus globulus in Uruguay

Eucalyptus globulus is the most important forest species in Uruguay, with more than 250,000 ha of commercial plantations. Despite its high susceptibility to diseases, production losses caused by foliar diseases have not been properly quantified in this country. This study analyzes the effects of foliar damage on growth and survival using data from a progeny test of E. globulus naturally infected by Teratosphaeria leaf disease and eucalypt rust (Puccinia psidii). The severity of leaf spots and defoliation were quantified 8 months after planting and tree growth and mortality were evaluated 2, 4 and 6 years later. The trial had a high incidence of foliar damage, with a mean leaf spot severity of 28.7% and a mean defoliation of 37%. The greatest impact of foliar damage, both on growth rate and mortality, occurred in the first 2 years after damage was assessed. During this period, leaf spot severity less than 40% and defoliation below 50% did not affect growth, while survival was affected when leaf damage was 70% or greater. By the sixth year both stem growth and survival were affected by severe foliar damage (spotting or defoliation of 80% or more), with a loss of up to 25% in diameter and an accumulated mortality over 70%. It has been established for the first time that under the intensive Uruguayan productive conditions, E. globulus trees can tolerate a relatively high degree of leaf spotting or defoliation but severe foliar damage in the first months can cause considerable production losses, putting at risk the economical viability of this species.     

肉桂油的成分研究

肉桂油在世界上享有盛名,产量占世界总产量的80％。作者用GC/MS联用仪对我国广东、广西、福建三省(区)的肉桂叶油和肉桂皮油进行了定性与定量分析。鉴定出广东肉桂叶油13个组分;广东肉桂皮油11个组分;广西肉桂叶油14个组分;广西肉桂皮油12个组分;福建肉桂叶油12个组分,结果表明五种肉桂油的化学组成基本相同,均以反式肉桂醛为主要成分,其含量分别为81.0,84.1,54.6,73.2和73.6％。     

Relationship between photosynthesis and leaf nitrogen concentration in ambient and elevated [CO2] in white birch seedlings

To study the effects of elevated CO2 concentration ([CO2]) on relationships between nitrogen (N) nutrition and foliar gas exchange parameters, white birch (Betula papyrifera Marsh.) seedlings were exposed to one of five N-supply regimes (10, 80, 150, 220, 290 mg N l(-1)) in either ambient [CO2] (360 micromol mol(-1)) or elevated [CO2] (720 micromol mol(-1)) in environment-controlled greenhouses. Foliar gas exchange and chlorophyll fluorescence were measured after 60 and 80 days of treatment. Photosynthesis showed a substantial down-regulation (up to 57%) in response to elevated [CO2] and the magnitude of the down-regulation generally decreased exponentially with increasing leaf N concentration. When measured at the growth [CO2], elevated [CO2] increased the overall rate of photosynthesis (P(n)) and instantaneous water-use efficiency (IWUE) by up to 69 and 236%, respectively, but decreased transpiration (E) and stomatal conductance (g(s)) in all N treatments. However, the degree of stimulation of photosynthesis by elevated [CO2] decreased as photosynthetic down-regulation increased from 60 days to 80 days of treatment. Elevated [CO2] significantly increased total photosynthetic electron transport in all N treatments at 60 days of treatment, but the effect was insignificant after 80 days of treatment. Both P(n) and IWUE generally increased with increasing leaf N concentration except at very high leaf N concentrations, where both P(n) and IWUE declined. The relationships of P(n) and IWUE with leaf N concentration were modeled with both a linear regression and a second-order polynomial function. Elevated [CO2] significantly and substantially increased the slope of the linear regression for IWUE, but had no significant effect on the slope for P(n). The optimal leaf N concentration for P(n) and IWUE derived from the polynomial function did not differ between the CO2 treatments when leaf N was expressed on a leaf area basis. However, the mass-based optimal leaf N concentration for P(n) was much lower in seedlings in elevated [CO2] than in ambient [CO2] (31.88 versus 37.00 mg g(-1)). Elevated [CO2] generally decreased mass-based leaf N concentration but had no significant effect on area-based leaf N concentration; however, maximum N concentration per unit leaf area was greater in elevated [CO2] than in ambient [CO2] (1.913 versus 1.547 g N m(-2)).     

Nutritive quality and morphological development under partial shade of some forage species with agroforestry potential

The shade environment produced in agroforestry practices affects the morphology, anatomy and chemical composition of intercropped forages and, therefore, may affect forage quality. During the summer-fall growing season of 1994 and 1995, 30 forage cultivars were grown in 7.6 L (two gallon) pots in full sun, 50%, and 80% shade created by placing shade cloth over a greenhouse frame. Fifteen legumes and grasses that were similar in yield under full sun and shade treatments were selected for quality analysis. With the exception of 'Kobe' lespedeza, D. paniculatum and D. canescens, acid detergent fiber (ADF) was either not affected or was slightly increased by shade. Except for Kobe lespedeza and 'Martin' tall fescue, shade either did not affect or slightly increased the neutral detergent fiber (NDF) of the shade-tolerant forages. Crude protein (CP) percentage increased in most shade-grown forages; however, shade had less effect on CP of legumes than of grasses. Other than Kobe lespedeza, total mass of CP per pot (TCP) was unaffected or increased under 50% shade for all species. Total crude protein of hog peanut, D. esmodium paniculatum and D. canescens was greater under both 50% shade and 80% shade than in full sun. The decrease in ADF of Kobe lespedeza, D. paniculatum and D. canescens under the shade treatments might be associated with maintenance of a higher leaf:stem weight ratio under shade. However, the leaf:stem ratios of the same cultivars grown at different light intensities did not strongly correlate with NDF, CP, and TCP values. In general, on selected species, internodal length and leaf area increased while specific leaf dry weight decreased for plants grown in shade compared to those grown in full sun. The data indicated that forage quality of some species could be enhanced by shade. This revised version was published online in June 2006 with corrections to the Cover Date.