Synthesis, Crystal Structure and Biological Activity of 5-(2-Methylphenyl)-1,3,4-oxadiazol-2(3H)-one Derivatives

3-Methyl-5-（2-methylphenyl）-1,3,4-oxadiazol-2（3H）-one （6） and N,N-diethyl-2-（2- methylbenzoyl）-hydrazinecarboxamide （7） were designed and synthesized from 5-（2-methyl- phenyl）- 1,3,4-oxadiazol-2（3H）-one （5） by substituting and ring-opening, respectively. The target compounds were confirmed by IR, JH NMR spectroscopy, MS, elemental analysis and single-crystal X-ray diffraction. Compound 6 （Cl0Hl0N202, Mr = 190.20） crystallizes in the triclinic system, space group P1 with a = 7.4645（16）, b = 10.868（2）, c = 12.970（3） A, α= 110.542（2）, β= 98.142（2）, γ= 99.766（2）°, V = 947.7（3） A3, Z = 4, F（000） = 400, Dc = 1.333 g/cm3, μ = 0.095 mm-1, the final R = 0.0550 and wR = 0.1483 for 2956 observed reflections with I〉 2σ（1）. Compound 7 （C13HI9N302, Mr = 249.31） crystallizes in the monoclinic system, space group C2/e with a = 18.926（3）, b = 12.1853（17）, e = 14.740（2） A, fl = 125.6380（10）~, V= 2762.7（7） A3, Z = 8, F（000） = 1072, Dc = 1.199 g/cm3,μ = 0.083 mm-1, the final R = 0.0554 and wR = 0.1468 for 2395 observed reflections with I 〉 2σ（I）. The preliminary bioassay results indicate that compound 6 exhibits notable fungicidal activities against Fusarium graminearum, Botrytis cinerea, Rhizoctonia cerealis and Colletotrichum capsici at the concentration of 100 μg/mL.

The Twin-Arginine Translocation (Tat) Pathway Is Essential for Virulence,Flagellation,and Chemotaxis in Xanthomonas oryzae pv. oryzicola Strain RsGD42

Bacterial leaf streak, caused by Xanthomonas oryzae pv. oryzicola, is an important disease of rice （Oryza sativa）. Genetic determinants （tatABC genes） of the twin-arginine translocation （Tat） pathway from X. oryzae pv. oryzicola strain RsGD42 were cloned and characterized, meanwhile, a tatC disruption mutant was generated. The tatC mutant lacked detectable flagella and was highly impaired in motility and chemotaxis. Furthermore, it was observed that the tatC mutant exhibited a reduced production of extracellular polysaccharide （EPS） and a significant reduction of virulence on adult rice plants compared to wild type strain. However, the tatC mutation in X. oryzae pv. oryzieola strain RsGD42 did not affect the growth rate and the ability to induce hypersensitive response （HR） in nonhost tobacco （Nicotiana tabacum L. cv. Samsun）. In conclusion, the data indicated that the Tat pathway significantly contributed to the virulence of X. oryzae pv. oryzicola.

Resistance Evaluation of Soybean Germplasm from Huanghuai Region to Phytophthora Root Rot

The aim of the study was to establish a set of differential strains and to identify soybean resistant genes to Phytophthora root rot and then to apply those strains for analysis of the resistant genes Rps1a,Rps1c,and Rps1k that soybean cultivars or lines may carry.Virulence formula of 125 Phytophthora sojae isolates were determined using the hypocotyls inoculation technique,the strains,which includ 6 isolates with different virulence formulas,were applied to identify the resistance of 55 soybean cultivars or lines and resistant genes were analyzed using the gene postulating procedure.Eighteen reaction types occurred in 55 cultivars or lines and results of gene postulation indicated that 2 cultivars or lines probably carried gene Rps1c and no cultivar may carry genes Rps1a or Rps1k.A few of soybean cultivars or lines from Huanghuai Region carry Rps genes Rps1a,Rps1c and Rps1k and tend to infect by P.sojae,so resistant cultivars or lines need to be bred and popularized actively.

Biological and biochemical characterization of a red-eye mutant in Nilaparvata lugens （Hemiptera： Delphacidae）

A red-eye colony was established in our laboratory in brown planthopper （BPH）, Nilaparvata lugens （Stal）, a major rice pest in Asia. Except for the red-eye phenotype, no other differences were observed between the wild-type （brown eye） and the mutant-type （red eye） in external characters. Genetic analysis revealed that the red-eye phenotype was controlled by a single autosomal recessive allele. Biological studies found that egg produc- tion and egg viability in the red-eye mutant colony were not significantly different from those in the wild-type BPH. Biochemical analysis and electronic microscopy examination revealed that the red-eye mutants contained decreased levels of both xanthommatin （brown） and pteridine （red） and reduced number of pigment granules. Thus, the changes of amount and ratio of the two pigments is the biochemical basis of this red-eye mutation. Our results indicate that the red-eye mutant gene （red） might be involved in one common gene locus shared by the two pigments in pigment transportation, pigment granule formation or some other processes.

Gene cloning and expression of aminopeptidase N and cadherin from midgut of the rice stem borer, Chilo suppressalis

The rice stem borer, Chilo suppressalis Walker is one of the most important insect pests on rice in Asia, north Africa and southern Europe. Transgenic Bt rice has been developed in the laboratory with good resistance to this pest and other Lepidopteran insects, which will provide a possible alternative tool for this pest control. The full-length cDNAs encoding an aminopeptidase N （CsAPN） and a cadherin （CsCad） were cloned from C. suppressalis. CsAPN showed common features of, and high identities to, other insect APNs in its deduced amino acid sequence. Although a full-length cDNA encoding cadherin-like protein has been reported in GenBank, the newly isolated cadherin here （CsCad） showed some differences in its amino acid sequence, especially at the 7th cadherin repeat region （CR7）, which indicated the newly isolated CsCad might be another allele. CsAPN and CsCad were successfully expressed in insect Tn cells, and the blot analysis showed these two proteins could bind Bt toxin CrylAb. The results will provide valuable information for the studies of toxin mode of action and the possible toxin resistance mechanisms in this pest.

Synthesis and bioactivity of novel 3-(1-hydroxyethylidene)-5-substituted-pyrrolidine-2,4-dione derivatives

3-(1-hydroxyethylidene ) 的十新奇 5 代用品衍生物 pyrrolidine-2,4-dione 被综合。混合物被红外， 1H NMR， MS 和元素的分析证实。生物鉴定分别地显示这些混合物显示出显著 herbicidal 活动，并且混合物 6f 和 6j 对 Echinochloa crusgalli 的梗展出了优秀禁止的活动，与 94.4 和 72.7 mg/L 的 EC50 价值。

Synthesis and bioactivity of novel strobilurin derivatives containing the pyrrolidine-2,4-dione moiety

（E）-Methyl-2-（2-（bromomethyl）phenyl）-3-methoxyacrylate was reacted with substituted 1-acetylpyr-rolidine-2,4-diones and 3-（1-（hydroxylamino）ethylidene）pyrrolidine-2,4-diones respectively to synthesize two series of/%methoxyacrylate derivatives containing the pyrrolidine-2,4-dione moiety. The structures of the targeted compounds were confirmed by IR, 1H NMR, 13C NMR, MS and elemental analysis. The fungicidal activity against Rhizoctonia solani, Botrytis cinerea and Fusarium graminearum was evaluated. The bioassay results demonstrated that these compounds showed visible fungicidal activity.