Light intensity affects the growth and flavonol biosynthesis of Ginkgo (Ginkgo biloba L.)

Response of growth and secondary metabolites to light intensity are useful measurements to determine suitable silviculture treatments for the cultivation of medicinal plants. Here, we analyzed the growth, flavonols (total flavonol, quercetin, kaempferol, and isorhamnetin) content, flavonols yield per plant, and expression of flavonoid biosynthesis-related genes in 2-year Ginkgo (Ginkgo biloba L.) seedlings at four different light intensities (100, 76, 40, and 25 % of full sunlight) in a greenhouse setting. Across all light intensities, the 76 % sunlight treatment produced the highest growth of total biomass, root, stem, and leaf, indicating negative effects of either fulllight or heavy shading on Ginkgo seedling development. Both flavonols (total flavonol, quercetin, kaempferol, and isorhamnetin) content and expression of flavonoid biosynthesis-related genes [PAL (Phenylalanine ammonia-lyase), CHS (Chalcone synthase), F3H (Flavanone 3-hydroxylase), and FLS (Flavonol synthase)] in leaves were highest under 100 % sunlight, suggesting that full sunlight promotes the expression of flavonoid biosynthesis-related genes and increases flavonoid biosynthesis. The highest and lowest flavonol contents were found in leaves and stems, respectively. The 76 % sunlight treatment produced the highest flavonols yield while the 100 % sunlight produced the highest flavonoids content in leaves, indicating that flavonol production per unit land area depends not only flavonol content but also biomass. Overall, in order to achieve the highest flavonols yield per area in Ginkgo leaf-harvesting plantations, it is important to manipulate light conditions of field.     

银杏叶黄酮研究进展

报道了近年银杏叶黄酮的最新研究进展;银杏叶黄酮生物体内合成代谢途径：遗传因子、生长发育进程、生态条件和栽培措施对银杏叶黄酮的影响;调控银杏叶黄酮的遗传和生理生化机制等,介绍了生物技术和化学合成在工厂化生产银杏黄酮方面的尝试,并对提高银杏叶黄酮含量的途径进行了评价及前景展望。     

短期降温-回温过程中银杏部分渗透调节物质的动态变化

研究了在短期降温—回温过程中2年生盆栽银杏叶中可溶性糖、可溶性蛋白、游离氨基酸和游离脯氨酸(Pro)质量分数的动态变化,结果表明:(1)随着温度的降低,叶中可溶性糖、可溶性蛋白、游离氨基酸质量分数升高,Pro质量分数先升高后降低,随着温度的回升,上述指标的变化规律与降温过程相反,说明银杏对短期变温做出了快速反应,即银杏叶中上述渗透调节物质代谢的水平和途径发生了一系列的适应性变化;(2)渐变过程升至25℃和骤变过程升至25℃时,上述4个指标值均高于变温前的水平,表明经过变温锻炼,银杏获得了一定的抗寒能力。     

Effects of environmental factors on seedling growth and anthocyanin content in <Emphasis Type="Italic">Betula</Emphasis> ‘Royal Frost’ leaves

Determining the influences of environmental factors on seedling growth and leaf color may improve our understanding of the chromogenic mechanisms in leaves and the biosynthesis of anthocyanin. To determine the optimum conditions for Betula ‘Royal Frost’ seedling cultivation, we assessed seedling growth and anthocyanin content under natural conditions. The temperature had a significant influence on height but not on radial growth. Between June and September, the anthocyanin content was significantly positively correlated with light intensity and air moisture and significantly negatively correlated with temperature. In single-factor experiments to determine the variation in anthocyanin content in the greenhouse, anthocyanin content increased with increasing soil water content and at first increased, then decreased with increasing pH of the irrigation water and temperature, but decreased with increasing light intensity. K₂SO₄ can increase the anthocyanin content. So to maintain leaf color, seedlings should be cultivated with < 200 μmol m^?2 s^?1 light intensity at 20 °C and soil moisture content between 60 and 90%, and the irrigation water should be neutral or alkaline. Additionally, spraying with K₂SO₄ can be beneficial.     

Severe outbreaks of the ash sawflyTomostethus nigritus F. (Hymenoptera: Tenthredinidae) on ornamental trees in oslo

During spring and summer 1990 observations on the biology of the ash sawfly,Tomostethus nigritus F. were made and control options discussed. The sawfly overwinters as an co- or pronymph in the soil, and pupates in earlys spring. The tlight period lasted for about 3 weeks. The larvae fed on the leaves till June. Injecting the systemic insecticide Carbicron 50 SCW (Dicrotophos) was successful.     

土壤水分含量对银杏叶黄酮和内酯含量的影响

以银杏全同胞家系2年生实生苗为试验材料，通过盆栽试验和室内分析相结合的方法对影响银杏叶片黄酮和内酯含量的土壤水分因子进行研究，结果表明：土壤水分含量银杏叶黄酮和内酯类物质含量的大小。适度缺水有利于黄酮和内酯类物质的积累，充足供水和水淹条件均不能有效地提高银杏叶黄酮和内酯的含量；银杏叶黄酮含量和内酯含量呈正相关关系。     

银杏种子黄酮与内酯含量变化

以银杏4个品种（马铃5号、马铃9号、金坠13号、金坠17号）的种子为试验材料,对不同时期银杏种子中的黄酮、内酯含量变化进行了系统研究。结果表明：不同品种间变化规律表现出相似性。在种子发育及采后层积过程中,黄酮含量呈现“减－增－减”的趋势。内酯的含量变化均为前期含量先减少,9月20日基本达到稳定状态,2月20日又呈下降趋势。     

不同生态因子对银杏生长的影响

用定位研究的方法,在丹东不同区域建立生态因子观测场,测定不同土层厚度、pH值、土壤养分含量、空气温湿度、光照强度、降雨、蒸发量等各因子对银杏生长的影响,结果表明:在不同的温度条件下,银杏种子萌发和幼苗生长状况不同,经20 d后,种子发芽率恒温比变温高6.2个百分点,幼苗根系生长、苗高、地径恒温比变温分别提高36.7%和16%。经过遮阴处理,银杏幼苗生长好于对照区。生长在壤土和沙壤土上的银杏其生长表现优于生长在沙土和黏土上的,土壤含盐量以0.03%～0.043%,银杏生长良好。银杏对pH值适应范围很宽,在pH值4～8.5的土壤上均能生长。     

Distribution and persistence ofSteinernema spp. andHeterorhabditis spp. (Nematodes) under different field conditions

The vertical and horizontal distribution, as well as the persistence ofSteinernema glaseri, S. carpocapsae (1192, I 100 and Mexican strains),Heterorhabditis bacteriophora, H. heliothidis andHeterorhabditis sp. were studied in three different soil types under field conditions. The presence of infective juveniles in soil samples taken at various depths was assessed usingGalleria mellonella larvae as baits for the nematodes. Results show that all tested nematodes had a similar pattern of vertical distribution. On the other hand,Heterorhabditis spp. were significantly more persistent thanSteinernema spp. in all soil types. As for the horizontal dispersal, none of the nematodes were ever found outside the treated plots, indicating that most of the juveniles remained near the point of application.     

银杏不同家系和无性系叶片黄酮与内酯含量变异

该试验以银杏20个半同胞家系和19个无性系为材料,对其叶片黄酮与内酯含量、光合速率、PAL活性及主枝生长量进行测定,同时对它们的广义遗传力及相互关系进行了研究,结果表明:不同家系和无性系间的银杏叶黄酮和内酯含量有显著的差异.家系叶片黄酮和内酯含量的广义遗传力为0.42和0.53,无性系叶片黄酮和内酯含量的广义遗传力为0.80和0.65,无性系叶片黄酮和内酯含量的广义遗传力显著高于家系.不同家系间和无性系间的银杏叶光合速率、PAL活性、相对生长量有显著差异,也具有较高的遗传力.叶用银杏家系黄酮含量、无性系黄酮含量的大小与叶片光合速率、PAL活性、相对生长量有显著的相关性,相关系数分别达0.76、0.58、0.61和0.69、0.78、0.95.     

Soil thermal and moisture regimes on forested slopes of an appalachian watershed

Soil thermal and moisture regimes were studied at four sites of contrasting slope positions and aspects within a forested Appalachian watershed (39° 41′N, 79° 45′W, elevation from 567 m to 796 m). The overall mean temperature for the 0–50 cm soil layer was 12.3°C in 1981; mean annual temperatures ranged from 13.3°C at 2 cm depth on a south-facing lower site to 11.0°C at 50 cm depth on a north-facing lower site. During the growing season soil temperatures of the south-facing lower site exceeded those of other sites by 1°C or less for soils less than 20 cm in depth. Maximum temperature differences between sites were reached in November, and the minimum temperature differences between sites were observed in January.The soil moisture content on the north-facing site exceeded that of all other sites. The south-facing lower site was the driest, while the south-facing upper site and the ridge top were intermediate and had similar moisture regimes. It was concluded that the moisture regime of the south-facing lower site was a joined effect of aspect and relatively high stoniness.     

不同肥料种类追肥对银杏生理活性物质含量的影响

试验详细分析了不同种类肥料对银杏生理特性的影响规律,以期为育苗中合理施肥提供理论依据。试验在田间条件下,设置无肥(对照,T1)、尿素(T2)、过磷酸钙(T3)、硫酸钾(T4)4个处理,3次重复。结果表明:5-10月,T4可溶性蛋白分别比对照提高了41.45%、70.21%、42.87%、28.99%、44.31%、216.41%,5-9月T2与T4之间无显著差异;可溶性糖含量分别提高了42.61%、46.65%、41.55%、48.15%、53.66%、60.23%,7月、10月T3显著低于T4;花色素苷含量分别提高了42.29%、84.86%、58.42%、67.62%、74.52%、80.81%,T2显著低于T4;黄酮含量分别提高了95.00%、88.71%,92.45%、118.18%、104.90%、110.45%,T2与T4之间无显著差异;叶绿素a含量提高了13.79%、15.69%、16.67%、22.08%、16.91%、20.73%,T2显著高于T4。综合分析认为,尿素、硫酸钾对银杏生理活性的影响优于过磷酸钙。     

人工气候箱条件下银杏的耐寒抗热生理机制

在人工气候箱中，用不同低温和高温条件胁迫银杏幼苗，测定了叶片离子相对渗透率、超氧化物歧化酶活性、过氧化物酶活性、脯氨酸和丙二醛含量的相关变化关系。研究结果表明：银杏抗热性能较差，但有一定抗寒能力。     

银杏树中黄酮类化合物分布规律研究

采用醇提法对银杏树不同部位黄酮类化合物进行提取,并利用紫外分光光度法对银杏树中黄酮类化合物含量进行了测定,对其分布规律进行了分析研究.结果表明银杏树中黄酮类化合物分布分别为:枝桠材中含0.035mg/g左右,主干材中含0.018mg/g左右,根材中含0.014mg/g左右;枝桠皮中含0.41mg/g左右,主干皮中含0.26mg/g左右,根皮中含0.12mg/g左右,苗木中含0.12mg/g左右.测定结果表明,不同部位的木材的黄酮类化合物含量有差异,从根部到枝桠再到叶,黄酮类化合物含量在增大.     

Evaluation of microbial and chemical insecticides for the control ofSpodoptera exigua (Lep., Noctuidae) on soybean plants

Field experiments have been carried out to evaluate the potency of the biological control agentBacillus thuringiensis (Dipel), the pyrethroid Fenvalerate and their combinations for the control of the lesser cotton leafwormSpodoptera exigua on soybeans in Qualubia governorate. Molasses was combined with all treatments to enhance their effectiveness. One spray application with either Dipel or Fenvalerate showed an obvious reduction in larval counts ofS. exigua, associated with a significant increase in the crop yield but in varying degrees, in correlation with the tested dose. Treatments with combinations of both biological and chemical insecticides at the lowest tested doses (62 g ofB. t. +50 ml of Fenvalerate/feddan) showed to be highly potential, and caused 2.8 fold increase in the crop yield. It may be recommended that a combination of both preparations may be used for the control ofS. exigua.     

加杨叶中黄酮类化合物及其相关成分关系

为探讨加杨叶中黄酮类化合物与其他相关成分的关系,测定了不同时期加杨叶中总黄酮类化合物、花青素、总酚、组织含水量、可溶性糖、可溶性蛋白质的含量,结合主成分分析法对各物质间的关系进行了研究。结果表明,总黄酮含量与花青素相对浓度、组织含水量与可溶性糖含量、花青素浓度与可溶性蛋白含量之间具有显著的正相关;总黄酮含量与组织含水量、花青素相对浓度与组织含水量具有显著的负相关。选取与总黄酮含量变化显著相关的花青素相对浓度和组织含水量两个主要因子进行了回归分析,建立了黄酮类化合物与组织含水量和花青素相对浓度的数学关系表达式。     

截干对银杏叶产量的影响

银杏截干对银杏叶产量有明显促进作用,截干30cm时,叶产量可提高13％,并能增加长枝总长度和长枝数量,截干可提高黄酮含量17％-50％,银杏采收时间以9—10月为宜。     

内源激素含量与银杏叶中类黄酮含量的关系

对银杏叶丛枝叶中内源激素和类黄酮含量进行全周期测定。结果表明 :早期脱落酸 (ABA)含量低 ,但在7月初有一次绝对值较低的含量峰 ,8月底后含量迅速上升 ,在 11月初达到含量最大值 ,含量峰与叶中类黄酮峰同步 ;乙烯 (ETH)在 7月初和 9月底形成 2次高峰 ,第 2次峰值较大 ,第 1次峰与叶中类黄酮峰平行 ,第 2次峰超前 ;细胞激动素 (CTKs)含量早期高 ,后波动次数较多 ,玉米素 (Zrs)与CTKs含量变化曲线极显著相关 ;赤霉素 (GA)含量早期较高 ,中后期含量较低 ,在 7月中旬、9月底 2次达到含量低谷 ;吲哚乙酸 (IAA)含量在 5月中旬、8月中旬、9月底出现 3次含量高峰 ,第 1次峰值最大 ;较高的ETH、ABA含量 ,较大的CTKs IAA值 ,较低的GA含量有利于叶类黄酮合成 ;在最低的IAA ABA、IAA ETH、CTKs ABA、CTKs ETH、GA ABA、GA ABA、GA ETH值时 ,相应地在银杏叶中有类黄酮合成高峰。讨论了内源激素与叶中类黄酮之间的关系。     

CO2超临界流体法提取银杏叶黄酮工艺的研究

通过正交试验对二氧化碳超临界流体法提取银杏叶中黄酮工艺进行研究。正交实验结果分析表明超临界流体萃取最佳工艺条件为：萃取压力35MPa,萃取温度50℃,萃取时间1．5h,夹带剂浓度90％。