星豹蛛对小菜蛾捕食作用的电泳检测研究

本研究应用聚丙烯酰胺凝胶电泳技术,对星豹蛛雌雄蛛(Pardosa astrigera)捕食猎物小菜蛾(Plutella ma-culipennis Curtis)前后酯酶同工酶的变化进行了电泳分析。结果表明,在星豹蛛体内可以检测到被捕食猎物的特有酯酶同工酶酶带,且雌蛛最佳检测时间为捕食后3～6h,雄蛛为6～9h,猎物在星豹蛛雌蛛体内的消化时间短于雄     

包膜尿素与普通尿素掺混施用方式对土壤脲酶及春玉米生长的影响

采用大田试验,以不施氮为对照,采用释放期为60 d的包膜控释尿素(30%)与普通尿素(70%)掺混,研究了其不同施用方式(侧施、底施、分层施)对土壤脲酶及春玉米叶片净光合速率、保护酶活性的影响。结果表明:相同施氮水平下,底施处理0~40 cm土壤脲酶活性显著高于侧施和CK,尤其是在春玉米抽雄、灌浆期,但底施与分层施处理间没有显著差异。其中0~20 cm土层底施处理脲酶均值高于分层施、侧施和CK,分别为4.03%、55.94%和58.01%;20~40 cm土层底施处理脲酶均值高于分层施、侧施和CK,分别为3.77%、57.07%和67.37%。各处理植株和籽粒全氮含量变化趋势也基本一致,均表现为底施分层施侧施CK。采用底施处理在抽雄与灌浆期较分层施、侧施和CK叶片净光合速率平均值分别高3.61%、11.42%和33.43%,同时底施还提高了叶片超氧化物岐化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性。与分层施、侧施、CK相比,采用包膜尿素与普通尿素掺混底施春玉米产量分别增加0.42%、5.81%、49.23%。采用包膜控释尿素与普通尿素掺混底施效果明显且减少成本,是适宜北京地区推广的施用方式。     

茶树CsSNAT基因的克隆与表达分析

为明确茶树SNAT基因的序列特征和表达特点,在茶树转录组测序的基础上以茶树(Camellia sinensis)品种舒茶早为试验材料,通过SMART^TM RACE技术克隆茶树褪黑素合成途径中关键限速酶5-羟色胺-N-乙酰转移酶CsSNAT基因的cDNA全长序列,并分析其基因结构和表达模式。结果表明,CsSNAT基因序列全长1 014 bp,其中包含742 bp的完整开放阅读框(ORF),编码247个氨基酸,预测等电点7.64,蛋白分子量27.36 kDa。氨基酸序列比对显示,CsSNAT蛋白与其他高等植物的SNAT蛋白具有较高同源性,与葡萄 VvSNAT(CBI31163)同源性最高,为66.19%。诱导蛋白最佳条件为温度28℃,异丙基-β-D-硫代半乳糖苷(IPTG)浓度0.5 mg·L^-1,诱导时间6 h,在上清液中可获得大量分子量为66 kDa的可溶性融合蛋白。实时定量 PCR 分析表明,CsSNAT在褪黑素处理6 h后表达量最高,为对照的3倍;茶尺蠖取食6 h后,CsSNAT表达显著上调。不同激素处理结果显示,CsSNAT受脱落酸(ABA)、茉莉酸甲酯(MeJA)和水杨酸(SA)诱导表达。本研究结果为5-羟色胺-N-乙酰转移酶功能研究奠定了一定的基础。     

设施条件下青菜间作大豆或芋艿控制斜纹夜蛾效果及对捕食性天敌多样性的影响

为探讨设施菜田间作控制害虫斜纹夜蛾(Spodoptera litura)的效果及对捕食性天敌多样性的影响,以在上海市浦东新区设施菜田设置的青菜间作大豆或芋艿为处理,以非间作设施青菜田为对照,对间作作物大豆或芋艿植株上诱集到的斜纹夜蛾幼虫和卵块进行了调查,并对各处理区和对照区青菜田捕食性天敌群落结构特征进行系统调查和分析。结果表明,在调查期内(7~9月),每100株大豆和芋艿诱集斜纹夜蛾幼虫分别为1 098.84±107.50头和1 260.78±126.16头,诱集斜纹夜蛾卵块数分别为17.45±1.31个和20.76±1.81个;与非间作青菜田相比,青菜田间作大豆或芋艿后斜纹夜蛾种群数量分别减少37.83%或45.89%;间作大豆或芋艿青菜田捕食性天敌分别隶属5目21科31种和5目21科32种,而非间作青菜田隶属5目19科26种;非间作青菜田捕食性天敌的优势种为拟环纹狼蛛(Lycosa pseudoamulata)和草间小黑蛛(Erigonidium graminicolum),而间作大豆或芋艿后天敌优势种群均为拟水狼蛛(Pirata subpiraticus)、拟环纹狼蛛(Lycosa pseudoamulata)和草间小黑蛛(Erigonidium graminicolum);间作大豆青菜田捕食性天敌的个体数量、丰富度、多样性指数分别为91.22±4.91头.100株?1、29.74±0.30、4.53±0.03,较非间作青菜田分别增加58.70%、25.27%、10.60%;间作芋艿青菜田捕食性天敌的个体数量、丰富度、多样性指数分别为92.09±5.03头.100株?1、29.96±0.35、4.54±0.03,较非间作青菜田分别增加60.21%、26.19%、11.00%。本研究结论可为上海地区发展设施青菜田间作大豆或芋艿种植模式提供参考依据。     

缺钾对茶树幼苗叶片叶绿素荧光特性的影响

为了探明缺钾对茶树叶片的光合电子传递、光能转化和利用等的影响机制,本研究以10月龄扦插瑞香茶[Camellia sinensis (L.) O. Kuntze cv. Ruixiang] 苗为试验材料,通过沙培试验,用含5个不同钾浓度（K 0、100、200、600、2000 mol/L）的营养液浇灌,每周3次,处理24周后,进行茶树叶片叶绿素荧光参数的测定。结果表明,缺钾处理茶树叶片OJIP曲线O点上升,P点下降,同时出现150 s处的L点和300 s处的K点两个新点;缺钾条件下,TRo/ABS (or Fv/Fm) (最大光化学效率)、ETo/ABS（电子传递的量子产额）、REo/ABS（还原量子效率）、PIabs（吸收光能的性能指数）和PICS（单位面积为基础的性能指数）下降,而VJ、VI和耗散能增加。总之,缺钾损伤了从PSⅡ供体侧到PSI的整个电子传递链,降低了光合电子传递能力;缺钾叶片还通过增加热耗散以保护叶片在强光下免遭光氧化伤害。     

基因芯片技术鉴定棉铃虫胁迫后棉花差异表达基因

棉花在受到植食性昆虫为害后基因表达会发生变化,筛选鉴定这些调控基因有助于解析昆虫诱导棉花抗虫性的分子机制。本研究以棉花(Gossypium spp.)(中12)为实验材料,分别从正常生长条件下的棉花(对照)和棉铃虫(Helicoverpa armigera Hübner)取食胁迫6、12、24和48h的棉花叶片(处理)中提取总RNA,采用Affymetrix棉花基因芯片进行了基因表达谱分析。结果表明,棉铃虫取食6h时,差异表达基因共有4109个(占28%),其中上调1917个,下调2192个;棉铃虫取食12h时,差异表达基因共有2605个(占18%),其中上调1326个,下调1279个;棉铃虫取食24h时,差异表达基因共有3213个(占22%),其中上调1424个,下调1789个;棉铃虫取食48h时,差异表达基因共有2763个(占19%),其中上调1450个,下调1313个。进行生物信息学分析后发现,这些基因功能涉及氧化应激响应、防御响应、信号转导、转录调控、黄酮类生物合成、萜类化合物合成与代谢以及源于多种氨基酸的罗勒生物碱生物合成等多个方面。另外,从芯片结果中鉴定获得调控棉花特异性挥发物的相关基因,发现法呢...     

水生植被原位恢复对底泥磷释放的影响

选取太湖五里湖水生植被生态重建大型围隔(105 m2)为试验区,进行了水质和沉积物内源释放2a的同步跟踪监测。结果表明,围隔内挺水植物区和沉水植物区PO34-—P和NH4+—N的年平均浓度分别比围隔外对照区下降了54.6%,46.7%和17.1%,13.8%;围隔内水质得到明显的改善。通过室内静态模拟不同实验区沉积物中磷酸根的释放实验,发现围隔内沉水植物区和挺水植物区PO34-—P的释放速率的年平均释放速率分别为0.23±0.42mg/(m2.d)和-0.38±0.65mg/(m2.d),明显低于围隔外对照区﹝1.13±1.31mg/(m2.d)﹞。因此重建和恢复湖泊水生植物系统能有效抑制内源磷酸盐向水体的释放。     

不同叶面肥对番茄植株生理生化及烟粉虱种群生态的影响

施肥可以影响植物的生长和营养状况,从而影响植食性昆虫的生长发育、繁殖和为害等。在室内条件下[(25±1)℃,L∶D=14 h∶10 h,70%~80%RH]研究了氨基酸叶面肥、植物营养素和支链氨基酸3种肥料叶面喷施对番茄植株生长及烟粉虱生长发育和繁殖的影响。结果表明,施氨基酸叶面肥处理能明显促进番茄植株生长,株高、叶片展幅、叶面积显著高于对照,其次为施植物营养素处理。不同叶面肥处理影响番茄叶片矿物质及营养物质含量(N和糖含量没有显著差异),P、蛋白质和游离氨基酸含量与番茄生长指标株高、叶片展幅、叶面积基本呈正比,而K则相反;不同处理间的叶片叶绿素和水含量基本无显著差异。不同叶面肥处理番茄植株上烟粉虱生长发育及生殖表现存在差异,发育历期在氨基酸叶面肥处理番茄上最长(22.95 d),其次为植物营养素处理(22.83 d),最短的为对照处理(21.78 d),显著短于氨基酸叶面肥和植物营养素处理;存活率总体受叶面肥影响不大;烟粉虱1龄若虫体型在支链氨基酸处理番茄上较大,对照上较小,但随着龄期的发育,氨基酸叶面肥处理番茄上的4龄若虫体型达到最大,对照上的仍为最小。烟粉虱雌成虫寿命在支链氨基酸处理番茄上最长(26.64 d),植物营养素上的最短(16.92 d),两者差异显著;产卵量在支链氨基酸处理番茄上最高(190.55粒),对照上的最低(119.91粒),差异达到显著水平。烟粉虱内禀增长率在植物营养素处理番茄上最高(0.474 9),而在氨基酸叶面肥处理上,内禀增长率与对照相比并没有明显提高(分别为0.406 4和0.405 4)。施肥在促进作物生长的同时,也为植食性昆虫提供了良好的营养条件,作物产量的增加和害虫为害造成的损失两者之间的平衡是获得收益的关键。本研究中氨基酸叶面肥能明显促进番茄生长,对烟粉虱取食产卵有利,但同时会延长烟粉虱的发育历期,且氨基酸叶面肥处理番茄上的烟粉虱雌成虫寿命和生殖力并非最高,抵消了营养对烟粉虱的有利作用。同时,氨基酸叶面肥不会提高烟粉虱的内禀增长率,也就是不会促进烟粉虱的种群增长,在生产中有良好的应用前景。     

高岭石在醋酸-醋酸铵缓冲体系中的溶解特征

室温下(25℃±1℃)采用间歇法(batchmethod)模拟研究高岭石在pH5.5、pH4.5和pH3.5的HAC/NH4AC缓冲液中的溶解。实验结果表明:质子能够促进高岭石Al和Si的释放,且Al、Si的释放能力随反应液酸度的增加而增强,Al、Si溶解的一致性与酸度有关。pH5.5时,可能因Al的沉积而导致整个实验期间Al、Si释放表观不一致;pH4.5和pH3.5时,反应前期Al优先释放,而在反应后期Al、Si趋于一致。pH5.5、pH4.5和pH3.5的HAC/NH4AC缓冲液中高岭石溶解速率分别为:3.09×10-14mol/(m2·s)、6.31×10-14mol/(m2·s)和1.13×10-13mol/(m2·s)。HAC/NH4AC缓冲液中质子作用下高岭石溶解反应级数和速率常数分别为0.28和1.12×10-12。     

免耕条件下不同量秸秆覆盖还田提高东北黑土区玉米光合性能和产量的效应

【目的】探究东北黑土长期免耕及不同秸秆覆盖还田量下玉米光合性能及产量的变化规律，为科学应用免耕秸秆覆盖还田技术提供理论支撑。【方法】东北黑土区保护性耕作定位试验始于2007年，设置5个处理，分别为传统垄作秸秆不还田(对照，CT)及免耕配合当季收获玉米秸秆量的0%、33%、67%和100%(NT-0、NT-33%、NT-67%、NT-100%)还田。于2021年玉米苗期、拔节期和抽雄期，测定玉米叶片净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)等光合参数，以及叶绿素含量和叶面积；于成熟期，测定籽粒产量及其构成因素。【结果】与CT处理相比，4个免耕秸秆覆盖处理不同程度地提高了苗期的Pn，以及拔节期和抽雄期玉米叶片的Pn、Gs和Tr;NT-67%和NT-33%、NT-100%处理还显著降低了拔节期和抽雄期的胞间二氧化碳浓度，显著提升了抽雄期叶片的叶绿素含量(P<0.05)。NT-100%处理在拔节期和抽雄期的光合效率最高，光合性能显著优于其他处理，NT-67%处理有个别指标略低于NT-100%，但仍与CT、NT-0和NT-33%处理差异显著。免耕结合秸秆覆盖还田提高了玉米穗的行...     

Herbivore-induced volatiles from tea (Camellia sinensis) plants and their involvement in intraplant communication and changes in endogenous nonvolatile metabolites

As a defense response to attacks by herbivores such as the smaller tea tortrix ( Adoxophyes honmai Yasuda), tea ( Camellia sinensis ) leaves emit numerous volatiles such as (Z)-3-hexen-1-ol, linalool, α-farnesene, benzyl nitrile, indole, nerolidol, and ocimenes in higher concentration. Attack of Kanzawa spider mites ( Tetranychus kanzawai Kishida), another major pest insect of tea crops, induced the emission of α-farnesene and ocimenes from tea leaves. The exogenous application of jasmonic acid to tea leaves induced a volatile blend that was similar, although not identical, to that induced by the smaller tea tortrix. Most of these herbivore-induced plant volatiles (HIPV) were not stored in the tea leaves but emitted after the herbivore attack. Both the adaxial and abaxial epidermal layers of tea leaves emitted blends of similar composition. Furthermore, HIPV such as α-farnesene were emitted mostly from damaged but not from undamaged leaf regions. A principal component analysis of metabolites (m/z 70-1000) in undamaged tea leaves exposed or not to HIPV suggests that external signaling via HIPV may lead to more drastic changes in the metabolite spectrum of tea leaves than internal signaling via vascular connections, although total catechin contents were slightly but not significantly increased in the external signaling via HIPV.     

Composition of the volatiles from intact and mechanically pierced tea aphid-tea shoot complexes and their attraction to natural enemies of the tea aphid

The volatile components from intact tea shoots (ITS), obtained by air entrainment, were identified by their mass spectra and retention times and confirmed by comparison with standard samples. They are E-2-hexenal, ocimene, Z-3-hexenyl acetate, Z-3-hexen-1-ol, butanoic acid-3-hexenyl ester, linalool, 1-octanol, geraniol, and indole. Volatiles from mechanically pierced tea shoots (MPTS) were identified as E-2-hexenal, ocimene, Z-3-hexen-1-ol, butanoic acid-3-hexenyl ester, linalool, geraniol, indole, E-2-hexenoic acid, Z-3-hexenyl formate, methyl salicylate, and benzyl alcohol, and volatiles from tea aphid-tea shoot complexes (TATSC) were identified as E-2-hexenal, ocimene, Z-3-hexenyl acetate, Z-3-hexen-1-ol, linalool, geraniol, indole, benzaldehyde, and E-2-hexenoic acid. Z-3-Hexen-1-ol is the main component in the three different types of volatiles, and the amount of benzaldehyde in TATSC volatiles is very ample. The attraction of the volatiles from ITS, MPTS, and TATSC, and the nine components of TATSC volatiles to the natural enemies, the coccinellid, Coccinella septempunctata, the parasite, Aphidius sp., and the lacewing, Chrysopa sinica, were determined by electroantennogram (EAG) and the wind tunnel bioassay. TATSC volatiles and benzaldehyde elicited much larger EAG responses and stronger upwind flight and arresting behavior from each natural enemy in the wind tunnel than other infochemicals.     

Behavioral responses of the diamondback moth, Plutella xylostella, to green leaf volatiles of Brassica oleracea subsp. capitata

Green leaf volatiles (GLVs) from Brassica oleracea subsp. capitata L. have been identified as 1-hexanol, (Z)-3-hexen-1-ol, 1-hexen-3-ol, hexanal, (E)-2-hexenal, hexyl acetate, and (Z)-3-hexenyl acetate, by their mass spectra and retention times in comparison with authentic samples. No isothiocyanates were found in the extract. The activity of these chemicals has been determined on mated and unmated males and females of the diamondback moth (DBM) Plutella xylostella in the laboratory (wind tunnel) and in the field. On unmated males, mixtures of (Z)-3-hexenyl acetate, (E)-2-hexenal, and (Z)-3-hexen-1-ol with the pheromone induced attractant/arresting behavior in 80-100% of the males tested, significantly higher than the effect induced by the pheromone alone. On mated males and unmated females the effect of the GLVs alone or in combination with the pheromone was poor, while on mated females these compounds elicited upwind flight and arresting behavior in 40-60% of the females assayed. There was no synergism when these chemicals were mixed with the pheromone. In the field, (Z)-3-hexenyl acetate, the most active GLV in laboratory tests, when mixed with the pheromone in 1:1 ratio, enhanced 6-7-fold the number of females and 20-30% the number of males caught by traps over those baited with the pheromone alone. Our results indicate that the enhancement of the attraction of both males and females of the DBM to traps baited with pheromone blended with the relatively inexpensive and environmentally safe (Z)-3-hexenyl acetate may be important for future control strategies of the pest.     

微波烫漂和速冻加工黑毛豆仁挥发性风味成分分析

采用固相微萃取（SPME）与气相色谱-质谱（GC-MS）联用技术,分析微波烫漂和速冻后新大粒1号黑毛豆仁挥发性风味成分的变化。结果表明：黑毛豆仁鲜样、微波烫漂和速冻处理后分别检测到31、34和32种挥发性风味成分,主要为醇类、醛类、酮类化合物。1-辛烯-3-酮、己醛、（E,Z）-2,6-壬二烯醛、1-戊烯-3-酮、（E...     

Aroma chemicals isolated and identified from leaves of Aloe arborescens Mill. Var. Natalensis Berger.

Extracts from leaves of aloe (Aloe arborescens Mill. var. natalensis Berger) were obtained using two methods: steam distillation under reduced pressure followed by dichloromethane extraction (DRP) and simultaneous purging and extraction (SPE). A total of 123 aroma chemicals were identified in the extracts obtained by both methods using gas chromatography and gas chromatography/mass spectrometry. There were 42 alcohols, 23 terpenoids, 21 aldehydes, 9 esters, 8 ketones, 6 acids, 5 phenols, and 9 miscellaneous compounds. The major aroma constituents of this extract by DRP were (Z)-3-hexenol (29.89%), (Z)-3-hexenal (18.86%), (E)-hexenal (7.31%), 4-methyl-3-pentenol (5.66%), and butanol (4.29%). The major aroma constituents of this extract by SPE were (E)-2-hexenal (45.46%), (Z)-3-hexenal (32.12%), hexanal (9.14%), (Z)-3-hexenol (1.60%), and 3-pentanone (1.41%). Terpenoids were also found as one of the major constituents. The fresh green note of aloe leaves is due to the presence of these C(6) alcohols and aldehydes as well as terpenoids.     

Effects of cyclamen mite (Phytonemus pallidus) and leaf beetle (Galerucella tenella) damage on volatile emission from strawberry (Fragaria x ananassa Duch.) plants and orientation of predatory mites (Neoseiulus cucumeris, N. californicus, and Euseius finlandicus)

Volatile emission profile of strawberry (Fragaria x ananassa Duch.) plants (cvs. Polka and Honeoye) damaged by cyclamen mite (Phytonemus pallidus Banks) or leaf beetle Galerucella tenella (L.) (cv. Polka) was analyzed to determine the potential of these strawberry plants to emit herbivore-induced volatiles. The total volatile emissions as well as emissions of many green leaf volatiles (e.g., (Z)-3-hexen-1-ol and (Z)-3-hexenyl acetate) and methyl salicylate were greater from cyclamen mite-damaged strawberry plants than from intact plants. Leaf beetle feeding increased emissions of monoterpenes (Z)-ocimene and (E)-beta-ocimene, sesquiterpenes (E)-beta-caryophyllene, (E,E)-alpha-farnesene, and germacrene-D, and a homoterpene (3E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) significantly. Nevertheless, the na?ve generalist predatory mites, Neoseiulus cucumeris, Neoseiulus californicus, and Euseius finlandicus did not prefer P. pallidus- or G. tenella-damaged plants over intact plants in a Y-tube olfactometer, suggesting that these predatory mite species are not attracted by the herbivore-induced volatiles being released from young strawberry plants.     

Volatile composition of four southern highbush blueberry cultivars and effect of growing location and harvest date

The volatile composition of four southern highbush blueberry cultivars ('Primadonna', 'Jewel', 'Snowchaser', and 'FL02-40') grown in two locations (Gainesville and Haines City, FL) and harvested multiple times was investigated. A total of 42 volatiles were identified, including 8 esters, 12 terpenoids, 11 aldehydes, 7 alcohols, and 4 ketones. Twelve of these volatiles are reported for the first time in highbush blueberries, with 10 being positively identified: (Z)-3-hexenal, (E,E)-2,4-hexadienal, (E,Z)-2,6-nonadienal, (E,E)-2,4-nonedienal, methyl 2-methylbutanoate, butyl acetate, 2-methylbutyl acetate, and geranyl acetate. The dominant volatiles were aldehydes followed by terpenoids and esters, with distinct varietal profiles. 'Primadonna' was characterized by a large amount of esters and C-6 aldehydes. In contrast, fewer than 4 esters were found in 'FL02-40' and 'Snowchaser', respectively, but they produced more terpenoids than 'Primadonna' and 'Jewel'. Location and/or harvest date affected the production of volatiles in 'Primadonna', but not so much in the other cultivars.