Water snails as paratenic hosts of Hymenolepididae Fuhrmann, 1907 in Czechoslovakia

The distribution of cysticercoids of Hymenolepididae Fuhrmann, 1907 parasitizing water birds (Anseriformes and Ralliformes) in Czechoslovakia was studied. A total of 2970 snail specimens (429 Lymnaea stagnalis (L.), 531 L. ovata (Drap.), 1, 462 L. peregra (O. F. Müll.), 158 L. auricularia (L.), 262 Planorbis planorbis (L.) and 65 Viviparus viviparus (L.)) were examined for this purpose. Among them, 122 snails were infected with cysticercoids of 13 cestode species (Dicranotaenia coronula (Dujardin, 1845), Diorchis inflata (Rudolphi, 1810), D. nyrocae Yamaguti, 1935, D. ransomi Schultz, 1940, Diploposthe laevis (Bloch, 1782), Echinocotyle rosetteri Blanchard, 1891, Fimbriaria fasciolaris (Pallas, 1781), Microsomacanthus compressa (Linton 1892), M. paracompressa (Czaplinski, 1956), M. paramicrosoma (Gasowska, 1931), M. spiralibursata (Czaplinski, 1956), Sobolevicanthus gracilis (Zeder, 1803), and S. octacantha (Krabbe, 1869).     

Survey for viruses infecting onion, garlic and leek crops in Iran

Surveys to identify virus diseases affecting garlic ( Allium sativum ), onion ( Allium cepa ) and Persian leek ( Allium ampeloprasum var. persicum ) were conducted from 1999 to 2002. Surveys covered different regions of Iran (Tehran [different vegetable markets, farmer fields and cultivation areas], Noushahr, Chalous, Roudbar, Sari, Hamadan, Touyserkan, Ghazvin and Jiroft). A total of 2045 (1285 garlic, 525 onion and 230 leek) samples showing symptoms of virus infection were collected and tested by ELISA; and in some cases tests were also confirmed by immunoelectron microscopy (IEM) for the presence of Allium viruses. ELISA results showed that the following viruses were detected: Onion yellow dwarf virus (OYDV), Leek yellow stripe virus (LYSV) (genus Potyvirus , family Potyviridae ), Garlic common latent virus (GarCLV), Shallot latent virus (SLV) (genus Carlavirus ), Garlic virus D (GarV-D), Garlic virus B (GarV-B) and Garlic virus C type (GarV-C) (genus Allexivirus ). None of the samples reacted with antibodies to Shallot yellow stripe virus (SYSV) genus Potyvirus , family Potyviridae ), Shallot virus X (ShVX) and Garlic virus A (GarV-A, genus Allexivirus ). GarCLV, SLV, GarV-D, GarV-B and GarV-C are reported for the first time from Allium crops in Iran.     

Synthesis of new aliphatic and aromatic phytotoxic derivatives of 2alpha,4alpha-dimethyl-8-oxabicyclo[3.2.1]oct-6-en-3-one

Several new compounds with potential herbicidal activity were synthesized from 2alpha,4alpha-dimethyl-6,7-exo-isopropylidenedioxy-8-oxabicyclo[3.2.1]octan-3-one (4). Seven aromatic alcohols were prepared by reaction of (4) with aryllithium reagents, where the aryl groups were 4-ethoxyphenyl (5, 70% yield), 4-ethylphenyl (6, 82% yield), 4-butylphenyl (7, 78% yield), 4-tert-butylphenyl (8, 81% yield), 2,4-dimethoxyphenyl (9, 75% yield), 2-ethylphenyl (10, 12% yield) and para-(4-bromophenoxy)phenyl (11, 24% yield). Reaction of the acetonide (4) with Grignard reagents formed also four aliphatic alcohols where the alkyl groups are ethyl (13, 78%), butyl (14, 85%), hexyl (15, 81%) and octyl (25, 92%). The alcohols (5), (6), (7), (8), (13), (14), (15) and (25) were reacted with thionyl chloride in pyridine, forming their respective alkenes (17, 76%), (18, 74%), (19, 83%), (20, 73%), (22, 78%), (26, 62%), (23, 77%) and (24, 66%). The effect of these compounds, at the concentration of 5.5 microg g(-1), on the development of radicle and aerial parts of Sorghum bicolor (L) Moench, Euphorbia heterophylla L, Brachiaria decumbens and Desmodium tortuosum DC was evaluated.     

Acaricidal properties of some synthetic unconjugated allenic anilides

Seven unconjugated allenic anilides with the allenic moiety situated at the 3, 4 position were synthesized and evaluated for acaricidal activity against Boophilus microplus (Canestrinii). The order of toxicity (% adult mortality) of the anilides against adult B. microplus at 0.5 μg tick^?1 was: N-(3-chloro-4-methyl-phenyl)-5-methylhexa-3, 4-dienamide, (I) = N-(4-bromophenyl)-5-methylhexa-3, 4-dienamide(III)(100%) > N-(4-bromophenyl)-deca-3, 4-dienamide (VI)(68%) > N-(3, 4-dichlorophenyl)-5-methylhexa-3, 4-dienamide (II) (32.3%) > N-(3, 4-dichlorophenyl)-5-methylhepta-3, 4-dienamide (IV) (28%) > N-(3-chloro-4-methylphenyl)-5-ethylhepta-3, 4-dienamide (VII) (24%) > N-(4-bromophenyl)-5-methylhepta-3, 4-dienamide (V) (20%). Comparison of the relative potencies (in parenthesis) at 1.5 μg tick^?1 of the anilides with three commercial acaricides: pyrenone, lindane and carbaryl, revealed the following orders of activities: in comparison with pyrenone: pyrenone = I = II (1) > VI(0.93) > II (0.67) > IV (0.55) > VII (0.46) > VI (0.37); in comparison with lindane: I = HI (6.06) > VI (5.65) > II (4.04) > IV (3.36) > VII (2.76) > V (2.39) > lindane (1.0). All anilides were more toxic than carbaryl which gave no mortality at 1.5 μg tick^?1. The need for developing more effective control agents for B. microplus is highlighted by the high levels of resistance found in some Jamaican populations of the pest. Resistance of the orders of 31- to 227-fold had been reported against lindane and between 15- and 67-fold to carbaryl.     

Acaricidal activities of paeonol and benzoic acid from Paeonia suffruticosa root bark and monoterpenoids against Tyrophagus putrescentiae (Acari: Acaridae)

The acaricidal activities of paeonol (2'-hydroxy-4'-methoxyacetophenone) and benzoic acid identified in the root bark of tree peony, Paeonia suffruticosa Andrews, against copra mite, Tyrophagus putrescentiae (Schrank), adults were examined using direct contact and vapour phase toxicity bioassays and compared with those of cinnamyl acetate, cinnamyl alcohol and 37 monoterpenoids as well as the acaricides benzyl benzoate, dibutyl phthalate and N,N-diethyl-m-toluamide (DEET). Based on LD(50) values in fabric piece contact toxicity bioassays, the acaricidal activities of benzoic acid (4.80 microg cm(-2)) and paeonol (5.29 microg cm(-2)) were comparable to that of benzyl benzoate (4.46 microg cm(-2)) but more pronounced than those of DEET (30.03 microg cm(-2)) and dibutyl phthalate (25.23 microg cm(-2)). In vapour phase toxicity bioassays, paeonol and benzoic acid were much more effective in closed containers than in open ones, indicating that the effects of these compounds were largely due to action in the vapour phase. As judged by 24 h LD(50) values, (1S)-(-)-verbenone (7.42 mg per disc) was the most toxic fumigant, followed by (1S)-(-)-camphor, (S)-(+)-carvone, (R)-(-)-linalool and (+/-)-camphor (10.45-18.18 mg). Potent fumigant toxicity was also observed with paeonol, (2S,5R)-(-)-menthone, (+/-)-citronellal, benzoic acid, (1S,4R)-(-)-alpha-thujone and (R)-(+)-pulegone (25.10-34.63 mg). Neither benzyl benzoate, DEET nor dibutyl phthalate caused fumigant toxicity. Paeonia root bark-derived materials, particularly paeonol and benzoic acid, as well as the monoterpenoids described, merit further study as potential acaricides or as leads for the control of T. putrescentiae.     

Identification of the molecular make-up of the Potato virus Y strain PVY(Z): genetic typing of PVY(Z)-NTN

Potato virus Y (PVY) strains were originally defined by interactions with different resistance genes in standard potato cultivars. Five distinct strain groups are defined that cause local or systemic hypersensitive responses (HRs) in genetic background with a corresponding N gene: PVY(O), PVY(N), PVY(C), PVY(Z), and PVY(E). The nucleotide sequences of multiple isolates of PVY(O) and PVY(N) differ from each other by ≈8% along their genomes. Additionally, complete genome sequences of multiple recombinant isolates are composed of segments of parental PVY(O) and PVY(N) sequences. Here, we report that recombinant isolate PVY-L26 induces an HR in potato 'Maris Bard' carrying the putative Nz gene, and is not recognized by two other resistance genes, Nc and Ny(tbr). These genetic responses in potato, combined with the inability of PVY-L26 to induce vein necrosis in tobacco, clearly define it as an isolate from the PVY(Z) strain group and provide the first information on genome structure and sequence of PVY(Z). The genome of PVY-L26 displays typical features of European NTN-type isolates with three recombinant junctions (PVY(EU-NTN)), and the PVY-L26 is named PVY(Z)-NTN. Three typical PVY(NTN) isolates and two PVY(N) isolates, all inducing vein necrosis in tobacco, were compared with PVY-L26. One PVY(NTN) isolate elicited HR reactions in Maris Bard, similar to PVY-L26, while two induced a severe systemic HR-like reaction quite different from the quasi-symptomless reaction induced by two PVY(N) isolates. 'Yukon Gold' potato from North America produced HR against several PVY(NTN) isolates, including PVY-L26, but only late and limited systemic necrosis against one PVY(N) isolate. Consequently, according to symptoms in potato indicators, both PVY(Z) and PVY(NTN) isolates appeared biologically very close and clearly distinct from PVY(O) and PVY(N) strain groups.     

Toxicity and feeding deterrence of crude toxin extracts of Lecanicillium (Verticillium) lecanii (Hyphomycetes) against sweet potato whitefly, Bemisia tabaci (Homoptera: Aleyrodidae)

Crude toxins [toxin(V3450) and toxin(Vp28,) extracted from Lecanicillium (Verticillium) lecanii (Zimmermann) Gams & Zare strain V3450 and Vp28 respectively] were tested for contact toxicity, feeding deterrence and repellent activity against the sweet potato whitefly, Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae). Both toxins showed ovicidal activity to eggs, with LC(50) values of 447 and 629 mg L(-1) respectively. Nymphs of B. tabaci were the most susceptible stages (LC(50) values were calculated at 111 mg L(-1) for toxin(V3450) and 216 mg L(-1) for toxin(Vp28)), and adults were the second most susceptible stages (48 h LC(50) values were calculated at 178 mg L(-1) for toxin(V3450) and 438 mg L(-1) for toxin(Vp28)). Applied to seedlings at a concentration of 400 mg L(-1), the toxins significantly (P < 0.001) reduced the hatching of whitefly eggs and the subsequent survival rate of the nymphs, and the emergence and fecundity of the progeny adults. Both toxins exhibited repellent activity at low concentration (100 mg L(-1)), with repellency index (RI) values of 0.645 for toxin(V3450) and 0.642 for toxin(Vp28), and antifeedant activity at high concentration (1000 mg L(-1)) to adults, with antifeedant index (AFI) values of 0.713 for toxin(V3450) and 0.749 for toxin(Vp28). The results of the present study demonstrate the toxicity, repellence and antifeedant properties of the fungi metabolite toxins on B. tabaci, which might develop as environmentally friendly plant protectant(s).     

Control of Aspergillus growth and aflatoxin production using natural maize phytochemicals under different conditions of water activity

The effects of the natural phytochemicals trans-cinnamic acid (CA) and ferulic acid (FA) alone at concentrations of 1-25 mM and in 16 combinations (M: mixtures) on growth and aflatoxin B(1) production by Aspergillus flavus Link and A. parasiticus Speare were evaluated. Studies on growth rate and aflatoxin B(1) production were carried out in vitro in relation to a water activity a(w) of 0.999, 0.971, 0.955 and 0.937. Overall, CA at concentrations of 10 and 20 mM and FA-CA mixtures M3 (20 + 5 mM respectively), M8 (25 + 5 mM), M9 (1 + 10 mM), M10 (10 + 10 mM), M11 (20 + 10 mM), M12 (25 + 10 mM), M13 (1 + 20 mM), M14 (10 + 20 mM), M15 (20 + 20 mM) and M16 (25 + 20 mM) were the treatments most effective at inhibiting growth of the four species assayed. All strains were much more sensitive to all natural phytochemicals tested on growth rate at a(w) = 0.937. CA and the FA-CA mixtures M1 (1 + 1 mM respectively), M4 (25 + 1 mM), M5 (1 + 5 mM), M6 (10 + 1 mM), M7 (20 + 1 mM), M8 (25 + 5 mM), M9 (1 + 10 mM), M10 (10 + 10 mM), M11 (20 + 10 mM), M12 (25 + 10 mM), M13 (1 + 20 mM), M14 (10 + 20 mM), M15 (20 + 20 mM) and M16 (25 + 20 mM) completely inhibited aflatoxin B(1) production by all strains at a(w) = 0.999, 0.971, 0.955 and 0.937. Decreased aflatoxin B(1) levels in comparison with the control were observed with FA at 1, 10, 20 and 25 mM with the strains RCM89, RCM108 and RCM38 at a(w) = 0.971, 0.955 and 0.999 respectively. The data show that CA and FA can be considered as effective fungitoxicants for A. flavus and A. parasiticus in in vitro assay. The information obtained is part of an ongoing study to determine their application at the storage level.     

嘧菌酯与三种外源硒对不同生命阶段斑马鱼的联合毒性

分别测定了嘧菌酯、3种外源硒 (亚硒酸钠、硒代蛋氨酸和纳米硒) 对水体模式生物斑马鱼不同生命阶段的单一急性毒性,以及等毒性配比的二元混合体系的联合急性毒性,并分别采用相加指数 (AI) 法、毒性单位 (TU) 法和混合毒性指数 (MTI) 法对其联合效应进行了评价。结果表明:斑马鱼3个生命阶段对亚硒酸钠的敏感性 (以96 h-LC₅₀ (致死中浓度) mg/L表示,其中mg指硒的质量) 顺序为:仔鱼(1.11 mg/L) >胚胎(1.48 mg/L) >成鱼(13.05 mg/L);对硒代蛋氨酸的敏感性:仔鱼(0.80 mg/L) >胚胎(1.03 mg/L) >成鱼(9.36 mg/L);对纳米硒的敏感性:成鱼(0.48 mg/L) >仔鱼(1.67 mg/L) >胚胎(4.32 mg/L)。除MTI法计算嘧菌酯与硒代蛋氨酸对成鱼表现为部分相加作用外,采用AI法、TU法和MTI法计算嘧菌酯与亚硒酸钠、硒代蛋氨酸和纳米硒对斑马鱼成鱼、仔鱼和胚胎的联合作用结果一致,均表现为拮抗作用。     

Genetic Analysis of Isolates of Botrytis cinerea Sensitive and Resistant to Benzimidazole and Dicarboximide Fungicides

ABSTRACT A total of 56 isolates of B. cinerea collected from ornamental crops from commercial greenhouses were examined by random amplified polymorphic DNA (RAPD) fingerprint analyses. Isolates were examined as two independent sets of 35 and 36 isolates, with 15 isolates common to both sets. The isolates had four phenotypes: 17 were sensitive to two commonly used fungicides, thiophanate-methyl (a benzimidazole) and vinclozolin (a dicarboximide) (S(T)S(V)); 18 were resistant to both fungicides (R(T)R(V)); 16 were resistant to thiophanate-methyl but sensitive to vinclozolin (R(T)S(V)); and 5 were sensitive to thiophanate-methyl but resistant to vinclozolin (S(T)R(V)). Relationships among the isolates were determined by cluster analyses of mean character differences using the unweighted pair group method using arithmetic average and cladograms were constructed. Isolates were clustered primarily by fungicide-sensitivity phenotype. In one set of greenhouse isolates, 6 of 10 S(T)S(V) isolates clustered together with a bootstrap confidence value of 91%. In the other fingerprint set of greenhouse isolates, 9 of 11 S(T)S(V) isolates clustered together and had a bootstrap confidence value of 98%. Isolates resistant to thiophanate-methyl, vinclozolin, or both fungicides usually were not clustered with other isolates or were clustered with isolates of the same phenotype. To further elucidate these relationships, variant isolates resistant to one or both fungicides were produced on fungicide-amended agar medium from 14 S(T)S(V) greenhouse isolates. These 14 S(T)S(V) parent isolates, 57 resistant variant isolates, and 11 resistant greenhouse isolates were analyzed as three independent RAPD fingerprint sets. Variants selected from eight S(T)S(V) parent isolates were resistant to both thiophanate-methyl and vinclozolin even though parent isolates were exposed to only one of the fungicides. Isolates resistant only to vinclozolin (S(T)R(V)) had fingerprint patterns similar to and clustered with those of parent isolates, while fingerprint patterns of isolates resistant to thiophanate-methyl (i.e., R(T)R(V) or R(T)S(V)), regardless of sensitivity to vinclozolin, clustered differently from both those of S(T)S(V) parent isolates and those of S(T)R(V) isolates derived from the same parent. R(T)R(V) and R(T)S(V) variant isolates derived from the same fungicide-sensitive parents only clustered with other variants having the same phenotype.     

农药对人体健康影响的风险评估

介绍了有关农药对人体健康风险评估的基本原则及程序。农药对人体健康的风险评估被许多国家政府机构和国际组织用作农药登记评审和农药安全性评价的重要依据,其风险评估程序包括危害性鉴定、剂量-反应评定、接触评定和风险描述四个步骤。危害性鉴定主要是研究农药可能对人体健康产生的影响;剂量-反应关系主要是研究对农药的不同接触水平可能导致的相应的影响健康的程度;接触评定是研究人们从食物、饮用水和其他各种可能途径中接触到的农药量,其中包括:饮食接触评定、职业接触评定和居住环境接触评定;风险描述是将危险鉴定、剂量-反应评定和接触评定的结果进行综合分析,来描述农药对公众健康总的影响。     

华南籼稻稻瘟病菌致病型单基因鉴别寄主筛选

采用35个单基因鉴别寄主、12个日本清泽鉴别寄主共47个具有已知基因的鉴别寄主,对147个籼稻稻瘟病菌株进行致病型鉴别研究.147个菌株被划分为28个不同的致病类型.优势致病型为I-04、I-02和I-01,这3个致病型的菌株数占参试菌株的74.8%,而且与其他致病型比较,它们的致病谱较广.研究结果表明,F80-1(Pi-k)、IRBL7(Pi-kp)、IRBL16(Pi-sh(1))、IRBL21(Pi-7(t))、IRBL3(Pi-i)、IRBL9(Pi-z)、IRBL19(Pi-3)、IRBL10(Pi-z5)、IRBL11(Pi-zt)、IRBL18(Pi-1)、IRBL10(Pi-2)、F128-1(Pi-ta2)、F145-2(Pi-b)和IRBL22(Pi-9(t))等14个单基因鉴别寄主对以广东为主的华南籼稻区稻瘟病菌具有较好的鉴别能力,其中尤以F80-1(Pi-k)、IRBL7(Pi-kp)、IRBL16(Pi-sh(1))、IRBL21(Pi-7(t))、IRBL3(Pi-i)、IRBL9(Pi-z)、IRBL19(Pi-3)和IRBL10(Pi-z5)等8个单基因鉴别寄主的鉴别能力最强,IRBL11(Pi-zt)、IRBL18(Pi-1)、IRBL10(Pi-2)、F128-1(Pi-ta2)、F145-2(Pi-b)和IRBL22(Pi-9(t))等6个单基因鉴别寄主可鉴别抗性反应表现型较相似的致病型,并可用于细分致病型.3个优势致病型I-04、I-02和I-01对F80-1(Pi-k)等上述8个单基因鉴别寄主的抗性反应表现型依次为RRSRSSSMR、SSSSSSSS和SSRSSSSR.     

Interrelationships Among SADIE Indices for Characterizing Spatial Patterns of Organisms

ABSTRACT The SADIE (spatial analysis by distance indices) methodology for data analysis is a useful approach for quantifying the patterns of organisms (in terms of patches and gaps) and testing for randomness of the patterns. We investigated the interrelationship among key SADIE indices: index for distance to regularity for a data set (I(a)), a global measure of aggregation or clustering; the local clustering indices (v(i) and v(j)), scaled distances to regularity for each individual sampling unit; and the averages of v(i) and v(j) across all sampling units, which are additional global measures of aggregation. We demonstrated that v(i) and v(j) are mathematically related to I(a) and showed conditions when I(a) and mean local clustering indices give very similar results. Overall differences in average v(i) and Iv(j) I values, and between I(a) and these averages, decreased with increasing size of the sampling grid in a simulation study. This was because one component of v(i) and v(j) (iY)-a measure of the distance to regularity under randomness for a given location (not a given count)-was found generally to vary little with location, except for locations near corners of the sampling grid. Nevertheless, because distance to regularity for individual observed counts was location-dependent, and this location effect varied with the observed counts value as well, a new-scaled index for each count x location combination may be warranted. The implications of these findings on epidemiological research are discussed.     

大黑和暗黑蛴螬危害花生的防治指标研究

花生种苗期大黑蛴螬和花生生长期大黑、暗黑蛴螬的虫口密度(X)与减产率(Y)呈明显的直线正相关,其相关式苗期网池接虫为Y=0.7245 0.004X±3.3957(r=0.9520,n=39);同步模拟为Y=0.4452 0.0040X±1.3959(r=0.9661,n=28);接虫示范为Y=0.1360 0.0074X±1.5888(r=0.9800,n=4);生长期接大黑金龟甲卵为Y=1.2927 0.0042X±3.2704(r=0.8993,n=36);接暗黑金龟卵为Y=0.7308 0.0042X±2.1344(r=0.9568,n=32)。研究分析提出花生种苗期防治指标为三龄大黑蛴螬每平方米2头;生长期防治指标为每平方米大黑卵3粒,暗黑卵5粒。     

Identification of Random Amplified Polymorphic DNA Markers Linked to the Co-4 Resistance Gene to Colletotrichum lindemuthianum in Common Bean

ABSTRACT New cultivars of the common bean (Phaseolus vulgaris) with durable resistance to anthracnose can be developed by pyramiding major resistance genes using marker-assisted selection. To this end, it is necessary to identify sources of resistance and molecular markers tightly linked to the resistance genes. The objectives of this work were to study the inheritance of resistance to anthracnose in the cultivar TO (carrying the Co-4 gene), to identify random amplified polymorphic DNA (RAPD) markers linked to Co-4, and to introgress this gene in the cultivar Rudá. Populations F(1), F(2), F(2:3), BC(1)s, and BC(1)r from the cross Rudá x TO were inoculated with race 65 of Colletotrichum lindemuthianum, causal agent of bean anthracnose. The phenotypic ratios (resistant/susceptible) were 3:1 in the F(2) population, 1:1 in the BC(1)s, and 1:0 in the BC(1)r, confirming that resistance to anthracnose in the cultivar TO was monogenic and dominant. Six RAPD markers linked to the Co-4 gene were identified, four in the coupling phase: OPY20(830C) (0.0 centimorgan [cM]), OPC08(900C) (9.7 cM), OPI16(850C) (14.3 cM), and OPJ01(1,380C) (18.1 cM); and two in the repulsion phase: OPB03(1,800T) (3.7 cM) and OPA18(830T) (17.4 cM). OPY20(830C) and OPB03(1,800T), used in association as a codominant pair, allowed the identification of the three genotypic classes with a high degree of confidence. Marker OPY20(830C), which is tightly linked to Co-4, is being used to assist in breeding for resistance to anthracnose.     

Intercepted Scolytidae (Coleoptera) at U.S. ports of Entry: 1985–2000

Since 1985, the U.S. Department of Agriculture, Animal and Plant Health Inspection Service has maintained the 'Port Information Network' (PIN) database for plant pests intercepted at the U.S. ports of entry. As of August 2001, PIN contained 6825 records of beetles (Coleoptera) in the family Scolytidae that had been intercepted during the years 1985–2000 from countries outside of North America. Of the 6825 scolytid interceptions, 2740 (40%) were identified to the species level, 2336 (34%) to only the genus level, and 1749 (26%) were identified to only the family level. Of the 49 identified scolytid genera, the 10 most common were Hypothenemus (821 interceptions), Pityogenes (662), Ips (544), Coccotrypes (520), Orthotomicus (461), Hylurgops (327), Hylurgus (266), Tomicus (194), Dryocoetes (166), and Hylastes (142). The 10 most common identified species were Pityogenes chalcographus (565 interceptions), Orthotomicus erosus (385), Hylurgops palliatus (295), Ips typographus (286), Hylurgus ligniperda (217), Ips sexdentatus (157), Tomicus piniperda (155), Hylastes ater (75), Hypothenemus hampei (62), and Polygraphus poligraphus (48). Of these 10 species, H. palliatus, H. ligniperda, and T. piniperda are known to be established in the continental U.S. The scolytids were intercepted from 117 different countries; the top 12 countries were Italy (1090 interceptions), Germany (756), Spain (457), Mexico (425), Jamaica (398), Belgium (352), France (261), China (255), Russia (247), India (224), U.K. (151), and Portugal (150). The scolytids were intercepted in 35 U.S. states and 97 port cities. In general, there was a positive relationship between the number of scolytid interceptions from individual countries and the value of the imports from those countries. Overall, 73% of the scolytids were found in solid wood packing materials, 22% in food or plants, and 5% in other or unspecified materials. The products most commonly associated with scolytid-infested wood packing materials were tiles, marble, machinery, steel, parts, ironware, granite, aluminum, slate, and iron. The food products and plants that were commonly infested with scolytids included nutmeg, palms, coffee beans, kola nuts, and macadamia nuts.     

溴氰菊酯酶联免疫吸附分析方法研究

建立了定量测定溴氰菊酯间接竞争酶联免疫吸附分析方法(ic-ELISA)。合成了半抗原1-羧基-(3'-苯氧基苯基)甲基-3-(2',2'-二溴乙烯基)-2,2-二甲基环丙基羧酸酯(Med)和N-2-(羧基丙基)氨基甲酰基-(3'-苯氧基苯基)甲基-3-(2',2'-二溴乙烯基)-2,2-二甲基环丙基羧酸酯(Di)。分别采用碳二亚胺法和混合酸酐法将半抗原与牛血清蛋白(BSA)和卵清蛋白(OVA)偶联制备了免疫原Di-BSA和包被原Di-OVA、Med-OVA。将制得的溴氰菊酯免疫原免疫动物获得多克隆抗体,经间接非竞争ELISA法测得其效价为2.5×105。通过对甲醇含量、离子强度、pH值等影响因素进行异源分析条件的优化,确立了溴氰菊酯间接竞争酶联免疫分析方法的最佳检测条件(30%甲醇、氯化钠0.4 mol/L、pH 7.5),并建立了标准竞争曲线。该方法的IC50值为0.55±0.05 mg/L,检测限(IC10)为3.76±0.35 μg/L,对大多数拟除虫菊酯无交叉反应。分别在自来水、河水和土壤样品中添加0.05 ~5.0 mg/L(或mg/kg)的溴氰菊酯,回收率分别为89.7% ~106.8%、82.4% ~101.7%、75.6% ~97.8%。     

河朔荛花根中抑菌活性成分研究

在活性追踪指导下,采用多种分离技术从河朔荛花根甲醇提取物中分离得到12个化合物,经核磁共振波谱、质谱等技术并结合相关文献确定其结构分别为1-己酸-2,3-硬脂酸甘油三酯( 1 )、β-谷甾醇( 2 )、月桂醇( 3 )、顺-十八碳-9-烯酸( 4 )、(2E)-庚基-3-(3, 4-二羟基苯基)丙烯酸酯( 5 )、(–)-pluviatolide( 6 )、1β-hydroxy-10β-H-guaia-4,11-dien-3-one( 7 )、异狼毒素( 8 )、新狼毒素B( 9 )、瑞香酚( 10 )、单棕榈酸甘油酯( 11 )和(+)-去甲络石甙元( 12 )。其中,化合物 3 、 4 和 6 ~ 12 均为首次从河朔荛花中分离得到。抑菌活性测定结果表明:异狼毒素( 8 )和新狼毒素B( 9 )对马铃薯晚疫病菌Phytophthora infestans菌丝生长和孢子萌发均表现出明显的抑制作用,其中对菌丝生长的EC₅₀值分别为68.4 μg/mL和44.9 μg/mL,对孢子萌发的EC₅₀值分别为25.1 μg/mL和14.0 μg/mL。     

Sorption of sulfuryl fluoride by food commodities

BACKGROUND: The use of sulfuryl fluoride, a structural fumigant for termite and woodborer control, has recently been expanded to treating stored food commodities and food facilities. There is, however, a lack of data on the sorption of sulfuryl fluoride by food commodities. Knowledge about sorption is important in the context of effective treatment and residues.RESULTS: When sulfuryl fluoride was applied at a dose of 50 g m(-3) to various food commodities (total 68) with 300 g per replicate in 0.75 L gas wash bottles (fumigation chambers) at 25 +/- 1 degrees C, in most cases (81%) the gas concentrations in the free space of the commodities exceeded 50 g m(-3) (range 51-80 g m(-3)) at the end of 24 h exposure. In chambers without the substrate, an average concentration of 49.7 g m(-3) was recorded. About 54% of the commodities showed low-level ( < or = 25%) sorption of sulfuryl fluoride, 34% showed medium-level (26-50%) sorption and only 12% were highly sorptive (>50%). The latter include white oats (terminal gas concentration 17.8 g m(-3)), some of the decorticated split pulses (24.0-29.3 g m(-3)), chickpea flour (26.3 g m(-3)), dried ginger (29.0 g m(-3)), refined wheat flour (30.3 g m(-3)) and coriander powder (40.5 g m(-3)). In unfumigated control commodities, owing to interfering volatiles, Fumiscope readings in the range 0-13 were noted.CONCLUSION: Sulfuryl fluoride has the advantage of a low or moderate level of sorption with the majority of the food commodities.     

Responses of water productivity to irrigation and N supply for hybrid maize seed production in an arid region of Northwest China

Water and nitrogen(N) are generally two of the most important factors in determining the crop productivity. Proper water and N managements are prerequisites for agriculture sustainable development in arid areas. Field experiments were conducted to study the responses of water productivity for crop yield(WP_(Y-ET)) and final biomass(WP_(B-ET)) of film-mulched hybrid maize seed production to different irrigation and N treatments in the Hexi Corridor, Northwest China during April to September in 2013 and also during April to September in 2014. Three irrigation levels(70%–65%, 60%–55%, and 50%–45% of the field capacity) combined with three N rates(500, 400, and 300 kg N/hm~2) were tested in 2013. The N treatments were adjusted to 500, 300, and 100 kg N/hm~2 in 2014. Results showed that the responses of WP_(Y-ET) and WP_(B-ET) to different irrigation amounts were different. WP_(Y-ET) was significantly reduced by lowering irrigation amounts while WP_(B-ET) stayed relatively insensitive to irrigation amounts. However, WP_(Y-ET) and WP_(B-ET) behaved consistently when subjected to different N treatments. There was a slight effect of reducing N input from 500 to 300 kg/hm~2 on the WP_(Y-ET) and WP_(B-ET), however, when reducing N input to 100 kg/hm~2, the values of WP_(Y-ET) and WP_(B-ET) were significantly reduced. Water is the primary factor and N is the secondary factor in determining both yield(Y) and final biomass(B). Partial factor productivity from applied N(PFP_N) was the maximum under the higher irrigation level and in lower N rate(100–300 kg N/hm~2) in both years(2013 and 2014). Lowering the irrigation amount significantly reduced evapotranspiration(ET), but ET did not vary with different N rates(100–500 kg N/hm~2). Both Y and B had robust linear relationships with ET, but the correlation between B and ET(R~2=0.8588) was much better than that between Y and ET(R~2=0.6062). When ET increased, WP_(Y-ET) linearly increased and WP_(B-ET) decreased. Taking the indices of Y, B, WP_(Y-ET), WP_(B-ET) and PFP_N into account, a higher irrigation level(70%–65% of the field capacity) and a lower N rate(100–300 kg N/hm~2) are recommended to be a proper irrigation and N application strategy for plastic film-mulched hybrid maize seed production in arid Northwest China.