两种植物源杀虫剂对甘薯小象甲的室内防效

为了探明两种植物源杀虫剂印楝素和茶皂素对甘薯小象甲室内防效,挖掘其防治甘薯小象甲的潜力,测定了两种植物源杀虫剂对甘薯小象甲的忌避和拒食效果。结果表明,两种试验药剂浓度越大对甘薯小象甲的忌避和拒食具有更好防效,茶皂素浓度10%、20%在48 h忌避率逐渐上升到100%;浓度大于5%时,甘薯小象甲出现了强烈的拒食行为,拒食率大于90%,且随着时间延长而增加。印楝素试验组在浓度600、120 mg/L时,印楝素对甘薯小象甲有较好的忌避作用,但是仅在浓度为600 mg/L时,表现出较好的拒食效果。     

用~(32)P标记测定楝科植物油对柑桔木虱的拒食作用

<正> 本文报道用~(32)P 标记柑桔枝芽条,研究楝科植物油对柑桔木虱(DiaphorinaCitri Kuwayama)的拒食作用。用定标器测得处理组(喷楝科植物油)虫体中的~(32)P 强度明显比对照组虫体巾的~(32)P 强度低,表明处理组的虫子比对照组的虫子吸食量小,2%苦楝(Melia azedarach)油和2%印楝(Azadirachta indica)油对柑桔木虱成虫在非选择条件下具有一定的拒食作用。用处理组和对照组的虫子所做     

苦楝种核乙醇抽提物对蔬菜害虫——斜纹夜蛾、莞菁的拒食试验初报

苦楝种核乙醇抽提物是一种植物质杀虫剂,它含有对害虫有拒食作用的拒食剂。经测定拒食剂基本上是蛋白质,糖,有机酸三萜类物质及其衍生物,根据其抗虫机理可分为抗生型、抑制型及嗅觉型三类。实验室已证明楝树的提取物对人和动物是完全无害的,对害虫不易产生抗药性,对益虫一般安全且有选择性,不同种的昆虫对楝科植物有效成份反应有很大的差异。     

广州地区美洲斑潜蝇寄生蜂种类及植物提取物对寄生蜂的影响

研究了广州地区美洲斑潜蝇寄生性天敌的种类及发生动态,以及华南毛蕨、苦瓜、飞机草等植物提取物对寄生蜂的影响。研究结果表明,广州地区美洲斑潜蝇寄生蜂有姬小蜂科、茧蜂科11种。主要寄生蜂为姬小蜂科种类,其中底比斯釉姬小蜂Chry socharis p entheus(W a lker)为寄生美洲斑潜蝇的优势寄生蜂,其次是丽灿姬小蜂Chry sonotomy ia f orm osa(W estw ood)和冈崎灿姬小蜂Ch.okazak ii(K am ijo)。研究了植物提取物对底比斯釉姬小蜂的羽化率和寄生率的影响,结果表明,植物提取物对寄生蜂是相对安全的,已商品化的印楝素乳油制剂对其也同样是安全的。     

骆驼蓬种子提取物对斜纹夜蛾的生物活性效应

用甲醇、乙醇、丙酮、氯仿、乙酸乙酯、苯、石油醚等7种溶剂对骆驼蓬种子进行冷浸提取。提取率分别为23．91％。18．68％．17．80％，18．49％，14．31％．15．13％，17．96％。7种提取物中．以种子乙醇提取物(ESPH)对斜纹夜蛾3龄幼虫的非选择性拒食活性最高。24h拒食率为70．15％。采用酸水总生物碱提取法对ESPH进行初步分离。得到氯仿、正丁醇、水及总生物碱萃取物。生物测定结果表明．总生物碱萃取物对斜纹夜蛾幼虫的生长发育抑制作用最为强烈，其次为氯仿萃取物。     

植物生长调节剂对鸦胆子扦插生根的影响

以鸦胆子为研究对象,研究ABT~(1#)、IBA、NAA三种不同植物生长调节剂在不同浓度下对鸦胆子硬枝扦插的影响。结果表明,在P0.05水平上,植物生长调节剂种类对鸦胆子扦插影响差异不显著,但生长调节剂浓度对其影响差异显著。随浓度升高,鸦胆子扦插生根率先增加后降低,浓度为700 mg·L~(-1)时,扦插生根率最高,浓度为1 000 mg·L~(-1)时,扦插生根率降低;随浓度升高,鸦胆子扦插一级根的数量和长度以及二级根数量均逐渐增加。     

喀斯特峰丛洼地4种典型植物蒸腾作用及其影响因素

[目的]对广西壮族自治区喀斯特峰丛洼地4种典型植物(甘蔗、五节芒、灰毛浆果楝和青冈)蒸腾作用及其影响因素进行研究,为进一步开展区域植被生态需水研究提供科学依据。[方法]于2015年4月至2016年1月对4种主要植物群落不同季节蒸腾速率(Tr)、叶面积指数(LAI)和相关环境因子开展现场观测。[结果]4种植物Tr夏季与春、秋、冬3季呈极显著差异(p0.01),不同植物类型其Tr也存在差异,其中,甘蔗Tr的季节变化为96.55~197.42g/(m2·h),五节芒为95.26~169.13g/(m2·h),灰毛浆果楝为97.20~239.11g/(m2·h),青冈四季Tr为81.65~124.42g/(m2·h)。4种植物Tr均与空气温度(Ta)呈极显著(p0.01)或显著正相关关系(p0.05),与土壤含水率(SWC),LAI,土壤容重(ρb),空气相对湿度(RH)呈显著或极显著相关关系。SWC和Ta对甘蔗Tr起主导作用,是主要决策变量;Ta是五节芒Tr的主要决策变量;SWC和ρb是灰毛浆果楝Tr的主要影响因子;LAI,SWC和Ta是青冈Tr的主要影响因子。[结论]研究区域4种典型植物蒸腾作用存在差异,且均呈季节性变化趋势,不同植物Tr影响因素不同,可通过人工诱导水、光、热等环境因子进而合理调控植被生态需水。     

印楝素对植物病原菌抑菌作用初步研究

印楝(Azadirachta indica A.Juss)系楝科楝属乔木,原产于印度与缅甸,广泛种植于热带、亚热带地区,在亚洲南部、非洲和南美洲的70多个国家已有分布[J].印楝是一种多用途树种,并含有以印楝素为主的多种能防虫、杀虫、杀菌的活性物质[2],在我国云南、四川、海南、广西、广东等地均有种植,其中云南省的种植面积最大.     

入侵植物假臭草和胜红蓟提取物的抑菌活性研究

假臭草和胜红蓟是我国南方常见的入侵植物,为了防治和利用其开发植物源抑菌剂,本试验采用牛津杯法检测了不同溶剂(70%乙醇、95%乙醇、石油醚和乙酸乙酯)提取物对28种病原微生物的抑菌活性,并评估了不同器官部位提取物的抑菌活性。结果表明,不同溶剂提取物抑菌活性有差异,假臭草70%乙醇提取物对金黄色葡萄球菌(Staphylococcus aureus)抑制活性最强,抑菌圈直径为26.28±0.75mm;胜红蓟95%乙醇提取物对腐生葡萄球菌(Staphylococcus epidermidi)抑制活性最好,抑菌圈直径为17.31±0.46 mm。此外,假臭草和胜红蓟70%乙醇不同部位提取物对金黄色葡萄球菌(Staphylococcus aureus)的抑菌作用表现为叶部提取物(22.31±0.34 mm和19.52±0.28 mm)茎部提取物(22.25±0.65 mm和12.75±0.45 mm)根部提取物(11.78±0.69 mm和9.05±0.53 mm)。假臭草提取物对12种细菌和1种真菌黑曲霉菌(Aspergillus niger)具有抑制效果;胜红蓟提取物对9种细菌具有抑制效果。本研究结果为进一步研发具有潜力的植物源抑菌剂奠定了理论基础。     

海藻提取物与养分配施对葡萄果实品质及养分吸收的影响

研究海藻提取与养分配施对葡萄果实品质和养分吸收的影响,以“阳光玫瑰”葡萄为试验材料,设置5个处理:NPK 水溶肥(CK)、0.375% 海藻提取物与NPK 水溶肥配施(T1)、0.75% 海藻提取物与NPK 水溶肥配施(T2)、1.5% 海藻提取物与NPK 水溶肥配施(T3)和3% 海藻提取物与NPK 水溶肥配施(T4)。结果表明,海藻提取物与NPK 水溶肥配施能增加葡萄单穗重、产量和SPAD 值,T1、T2 和T3 处理果实可溶性糖和糖酸比含量分别较CK 提高77.98%、17.51%、1.42% 和69.45%、35.65%、11.45%,T4 处理降低果实可溶性糖和糖酸比含量。T2 处理果实磷含量和叶片钾含量最高,较CK 分别显著提高26.97% 和47.87%。此外,海藻提取物与NPK 水溶肥配施均增加果实香气化合物种类,其中,T2 处理果实香气化合物种类数最高。主成分分析中,T2 处理的葡萄果实产量、品质、养分吸收和果实香气物质影响中得分最高。综合分析,海藻提取物与养分一定比例配施能够提高葡萄产量、改善品质、促进养分吸收以及增加果实香气物质种类和相对含量,其中,0.75% 海藻提取物与NPK 水溶肥配施处理效果更佳。     

Novel mechanism of modulating natural antioxidants in functional foods: involvement of plant growth promoting Rhizobacteria NRRL B-30488

The significance of plant growth-promoting rhizobacteria (PGPR) mediated increase in antioxidant potential in vegetables is yet unknown. The plant growth-promoting bacterium Bacillus lentimorbus NRRL B-30488 (B-30488) mediated induction of dietary antioxidant in vegetables ( Trigonella foenum-graecum, Lactuca sativa, Spinacia oleracea, and Daucus carota) and fruit ( Citrus sinensis) after minimal processing (fresh, boiled, and frozen) was tested by estimating the total phenol content, level of antioxidant enzymes, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide scavenging activities along with integral radical scavenging capacity by photochemiluminescence assay and inhibition of lipid peroxidation. Minimal processing of vegetables showed that T. foenum-graecum had the highest phenol content in B-30488-treated plants followed by L. sativa, D. carota, and S. oleracea. Thermally treated vegetables T. foenum-graecum (26-114.5 GAE microg mg (-1)) had an exceptionally high total phenolic content, followed by D. carota (25.27-101.32 GAE microg mg (-1)), L. sativa (23.22-101.10 GAE microg mg (-1)), and S. oleracea (21.87-87.57 GAE microg mg (-1)). Among the vegetables and fruit used in this study for enzymatic estimation, induction of antioxidant enzymes, namely, polyphenol oxidase (PPO), ascorbate peroxidase (APX), catalase (CAT), and superoxidase dismutase (SOD), was observed in edible parts of T. foenum-graecum, L. sativa, S. oleracea, and D. carota, after inoculation with B-30488. The scavenging capacity of the vegetables treated with B-30488 against DPPH and superoxide anion radical activity was found to be significantly high as compared to nontreated control. Mild food processing had no adverse effect on radical scavenging capacity. Photochemiluminescence also ascertains the above findings. The ability of the plant extracts to protect against lipid peroxidation and its ability to prevent oxidation of reduced glutathione (GSH) was measured in rat liver homogenate, and the results suggested that the inoculated plant exhibited better activity in all of the screened plants. Significant increases in shoot length, root length, and dry weight, averaging 164, 132, and 135% in T. foenum-graecum, 174, 141, and 156% in L. sativa, 129, 141, and 59%, in S. oleracea, and 125, 146, and 42% in D. carota, respectively, over untreated controls, were attained in greenhouse trials. To the best of the authors' knowledge, this is the first report of PGPR-mediated induction of antioxidant enzyme activity (PPO, APX, CAT, and SOD) along with the antioxidant activity of the extracts in both in vitro (DPPH radical scavenging and superoxide scavenging) and ex vivo conditions using the rat liver tissue (percent inhibition of lipid peroxidation and prevention of oxidation of GSH) and phenolic content. The results demonstrate the PGPR-mediated induction of antioxidant level in vegetables and fruit controls oxidative damage even after minimal processing and thus is indicative of its potential as a viable substitute of synthetic antioxidants.     

Antimicrobial activity of Tunisian quince (Cydonia oblonga Miller) pulp and peel polyphenolic extracts

Quince (Cydonia oblonga Miller) fruit aqueous acetone extracts were evaluated. High-performance liquid chromatography-diode array detection and electrospray ionization-mass spectrometry were used for the identification and quantification of the phenolic compounds. The total phenolic content of the pulp and peel parts ranged from 37 to 47 and 105 to 157 mg/100 g of fresh weight, respectively. Chlorogenic acid (5-O-caffeoylquinic acid) was the most abundant phenolic compound in the pulp (37%), whereas rutin (quercetin 3-O-rutinoside) was the main one in the peel (36%). The radical scavenging potential of the extracts was determined and compared with that of synthetic antioxidants. The stronger properties corresponded to those obtained from peel material with a 70-80% inhibitory effect on DPPH radicals. The antimicrobial activity of the extracts against different microorganism strains was also investigated. Quince peel extract was the most active for inhibiting bacteria growth with minimum inhibitory and bactericide concentrations in the range of 102-5 x 103 microg polyphenol/mL. It seems that chlorogenic acid acts in synergism with other components of the extracts to exhibit their total antimicrobial activities.     

高湿贮藏对茄子冷害及抗氧化系统的影响

为探讨高湿贮藏对减轻茄子冷害的作用及其与抗氧化系统的关系,本试验将茄子果实分别放置于4℃的干雾控湿高湿冷库(相对湿度96%~99%)和低湿冷库(相对湿度70%~75%)中贮藏15 d,每隔3 d进行取样测定,比较分析相关指标的变化。结果表明,与低湿贮藏相比,高湿贮藏能显著抑制茄子果实冷害指数、相对电导率和失重率的上升(P<0.05),保持茄子果实较高的硬度及总酚和花青素含量。同时,高湿贮藏能显著提高茄子果实中超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)、过氧化氢酶(CAT)和过氧化物酶(POD)等抗氧化酶的活性(P<0.05),抑制过氧化氢(H₂O₂)和超氧阴离子( {\mathrm{O}}_2^{\frac{-}{·}} )的产生,保持更高的1,1-二苯基-2-三硝基苯肼(DPPH)和羟基自由基清除能力。上述结果表明,高湿贮藏可维持茄子果实较高的抗氧化系统活性,从而抑制活性氧对茄子的伤害,减轻果实冷害。本研究为高湿贮藏在茄子果实采后保鲜中的应用提供了一定的依据。     

林火前后坡面覆盖类型对产流产沙影响的模拟试验

通过室内模拟降雨试验,设置3种降雨强度(30,60,90 mm/h)和3种地表覆盖类型(裸土坡面、1 cm马尾松枯落物覆盖、1 cm马尾松灰烬覆盖),研究林火发生前后不同地表覆盖下的坡面产流产沙过程,明确枯落物和植物灰烬覆盖的减流减沙效益。结果表明:(1)相比裸坡,枯落物和灰烬覆盖下的坡面初始产流时间分别延长33%~80%和51%~200%,灰烬覆盖对延缓产流的效果更为明显;(2)相比裸坡,枯落物覆盖的减流效果稳定在12%~36%,而灰烬覆盖在中小雨强的减流效果高于70%,在90 mm/h雨强时减流效果降低至7%;(3)裸土坡面产流呈现先快速升高后稳定的趋势,而枯落物和灰烬覆盖坡面产流效果呈现"阶梯"形上升趋势;(4)枯落物覆盖能够减小径流携沙量和总产沙量,在3种雨强下减沙效益均高于85%,且高于同雨强下灰烬覆盖的减沙效益。枯落物覆盖的减流减沙效果在不同雨强下表现较为稳定,而灰烬覆盖的减流减沙效果受降雨强度的影响显著,且枯落物覆盖的减沙效益在3种雨强下均优于灰烬覆盖,说明在林火发生后地表覆盖改变是引起土壤侵蚀增加的重要因素之一。     

花生种子吸胀期间耐低温性及其与品质性状的相关研究

利用55份花生种子进行低温吸胀萌发试验,统计露白率及芽长/种长,筛选耐低温种质,并通过近红外光谱技术测定油酸、亚油酸、棕榈酸、脂肪、蛋白质及蔗糖含量,分析花生种子吸胀期间耐低温性与各项品质性状之间的相关性.结果表明:参试花生种质在2℃96h低温胁迫条件下,露白率≥80%的种质有3份、80%＞露白率≥70%的种质有3份、...     

番茄果实品质和叶片保护酶对水肥水平的响应

通过3个土壤相对含水量（W1,50%～60%; W2,7～0%80%; W3,90%～100%）和3个施肥水平（F1,N 0.187 g/kg+ P2O5 0.131 g/kg; F2,N 0.267g/kg+ P2O5 0.187 g/kg; F3,N 0.347 g/kg+ P2O5 0.243 g/kg）共9个处理的盆栽试验,研究了番茄结果期果实品质、叶片保护酶及叶绿素含量的变化规律,旨在为番茄结果期合理的水肥管理提供理论依据。结果表明: 在整个结果期,W1F2处理有利于提高果实品质; W2F2处理下果实中的渗透物质（游离氨基酸）保持着较高水平,且叶片保护酶活性较高,丙二醛含量低; W2F3处理的叶片叶绿素含量保持较高水平,W2F2处理番茄果实单株产量高。相关分析表明: 果实品质与超氧化物歧化酶、叶绿素含量呈正相关,而与丙二醛含量呈负相关; 游离氨基酸含量与过氧化物酶活性、脯氨酸含量呈显著正相关,而与丙二醛含量呈显著负相关。综合分析,番茄结果期较优的水肥组合为N 0.267g/kg+P2O5 0.187g/kg和70%80%的土壤相对含水量。     

Antioxidant properties of various solvent extracts of total phenolic constituents from three different agroclimatic origins of drumstick tree (Moringa oleifera Lam.) leaves

Water, aqueous methanol, and aqueous ethanol extracts of freeze-dried leaves of Moringa oleifera Lam. from different agroclimatic regions were examined for radical scavenging capacities and antioxidant activities. All leaf extracts were capable of scavenging peroxyl and superoxyl radicals. Similar scavenging activities for different solvent extracts of each collection were found for the stable 1,1-diphenyl 2-picrylhydrazyl (DPPH(*)) radical. Among the three different moringa samples, both methanol and ethanol extracts of Indian origins showed the highest antioxidant activities, 65.1 and 66.8%, respectively, in the beta-carotene-linoleic acid system. Nonetheless, increasing concentration of all the extracts had significantly (P < 0.05) increased reducing power, which may in part be responsible for their antioxidant activity. The major bioactive compounds of phenolics were found to be flavonoid groups such as quercetin and kaempferol. On the basis of the results obtained, moringa leaves are found to be a potential source of natural antioxidants due to their marked antioxidant activity. This is the first report on the antioxidant properties of the extracts from freeze-dried moringa leaves. Overall, both methanol (80%) and ethanol (70%) were found to be the best solvents for the extraction of antioxidant compounds from moringa leaves.     

Antioxidant contents and antioxidative properties of traditional rye breads

The purpose of this research was to find out the effect of flour extraction rate on the antioxidative properties of traditional rye bread and then to compare the bioactive compounds content and antioxidant properties of rye breads with commercial wheat roll. Four types of rye flour with different extraction rates of 100 (whole meal dark flour), 95 (brown flour), 90 (brown flour), and 70% (light flour) originated from Warko rye cultivar were used for traditional bread baking with sourdough fermentation. Four types of the respective rye breads were analyzed for their potentially beneficial components, including tocopherols and tocotrienols, total phenolics and flavonoids, reduced glutathione, and inositol hexaphosphates. Moreover, the phenolic acids profile was provided. The Trolox equivalent antioxidant capacity (TEAC) of the breads was evaluated using free radical scavenging activities of 80% methanol extracts against ABTS*+ radical cation (ABTS radical cation decolorization method) whereas radical scavenging activity (RSA) was determined against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH*). The superoxide dismutase-like activity (SOD-like activity) was evaluated as free radical scavenging activities of PBS extracts against superoxide anion radicals (O2*-). The results were compared to whole meal rye bread as well as to wheat roll taken as representative example of wheat based bakery product. The studies showed that flour extraction rates strongly affected the content of bioactive compounds and antioxidative properties of traditionally baked rye breads. The incorporation of the rye flours with extraction rates from 100 down to 70% in the formulation caused decrease in tocopherol (T), tocotrienol (T3), inositol hexaphosphate (IP6), and phenolic compound (TPC) contents in rye breads. No changes in reduced glutathione (GSH) contents were noted between each type of rye bread. A significant decrease in Trolox equivalent antioxidant capacity and radical DDPH scavenging activity was also found in bread formulated on flour with an extraction rate of 70% in comparison to the breads formulated on flour with extraction rates from 100 to 90%. The highest SOD-like activity was noted for rye bread formulated on flour with an extraction rate of 70%. The four types of rye breads showed better antioxidative properties and higher antioxidant contents when compared to wheat roll with one exception made to tocopherols and tocotrienols.     

充分灌与调亏灌溉条件下苹果树微喷灌的耗水量研究

田间试验设置有两个处理：整个生育期以蒸发量的80％灌溉的充分灌处理；6月中旬到7月中旬以蒸发量的40％灌溉，而其它季节恢复以蒸发量的80％灌溉的调亏灌溉处理（RDI）。 试验得出了苹果树微喷灌在上述两种灌溉条件下不同生育期的日均耗水量与蒸发皿系数。与充分灌比较，调亏灌溉处理的产量基本上没有受到影响，而灌水量减少了17%～20％，耗水量减少了10.2%～11.2%，并有效地抑制了枝条生长。     

土壤水分状况对温室青茄水分利用和外观品质的影响

为确定温室青茄优质高效的灌溉指标, 采用小区试验方法, 研究了不同生育阶段土壤水分状况对滴灌条件下温室青茄耗水量、产量、水分利用效率及果实外观品质的影响。研究结果表明, 任何时段水分亏缺均会降低青茄的耗水量; 温室青茄果实大小、坐果数以及最终产量均随水分亏缺程度的增大而减小, 产量、水分利用均与耗水量呈现良好的二次抛物线关系, 最优耗水量在307.12~339.59 mm 之间。当青茄土壤水分(占田间持水量的百分比)下限控制在苗期60%~70%、开花坐果期和成熟采摘期均为70%时, 产量及坐果率较高, 水分利用效率较佳, 可作为滴灌条件下温室青茄适宜的土壤水分控制指标。