Cleaner and convenient preparation of 3-（4,6-dimethoxy-pyrimidin-2-yloxy）-2-methyl-phenol

Environmental concerns have highlighted the need of cleaner technologies. A cleaner, convenient and selective technology has been developed for the preparation of 3-(4,6-dimethoxy-pyrimidin-2-yloxy)-2-methyl-phenol (DPMP) from 2-methyl-benzene-1,3-diol in water as solvent. The isolated yield of DPMP is up to 86% in good selectivity. The product structure was characterized by conventional methods, 1^H-NMR and MS. This technology belongs to the modern concept of environmentally friendly low wastes or non-wastes technology (LWNWT).     

Agrobacterium-mediated transformation of herbicide resistance in creeping bentgrass and colonial bentgrass

Embryogenic calli were induced from the seeds of creeping bentgrass ( Agrostis palustris Huds. ) cv. Regent and colonial bentgrass ( Agrostis Tenuis Sibth. F1. Oxen. ) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4-7 days and then co-cultivated with Agrobacterium tumefaciens, LBA4404,which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding region and matrix attachment region (MAR) . After 3 days of co-cultivation, the calli were washed thoroughly and transferred to MS medium containing 2 mg/L of 2, 4-D, 12-15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2-3 months of selection, the actively growing calli of ‘Regent‘ and ‘Ti-ger‘ were transferred to MS medium with 12-15 mg/L PPT and 250 mg/L cefotaxime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4 % of herbi-cide Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants and its absence in a randomly selected control plant.     

PTC法合成醋酸苄酯与机理探讨

该文描述了相转移催化剂存在时合成醋酸苄酯的机理，对反应温度、反应时间等因素也进行了讨论．     

香港郊野公园薇甘菊的化学防除研究

在香港郊野公园内选择薇甘菊危害较严重的草灌丛、灌木林和常绿阔叶林3种群落类型，设置样地5 000 m2，用0.05～0.1 g#8226;m-2嘧磺隆对样地中的薇甘菊进行化学防除试验, 并在施用除草剂后3、5和14个月跟踪调查施药对薇甘菊的杀灭效果以及对样地中其他植物和群落物种多样性的影响.结果表明嘧磺隆对样地薇甘菊有极好的杀灭效果.施药后3个月，样地中有45种植物产生了不同程度上的影响，占样地内所有种类的30%.受影响最大的是藤本和草本植物，其次是灌木，乔木受影响最小.施药后14个月，乔木和灌木生长正常, 草本植物基本恢复.施药清除薇甘菊后，能大幅度地增加群落的物种多样性.     

马铃薯前茬忌用除草剂

若前茬用过普施特(咪草烟、咪唑乙烟酸),需间隔36个月才能种马铃薯;若前茬用过氯嘧磺隆(豆草隆、豆磺隆),需间隔40个月才能种马铃薯;若前茬使用玉农乐(烟嘧磺隆),每公顷用量超过有效成分60克,即4%玉农乐(烟嘧磺隆)每亩超过100毫升,需间隔18个月才能种马铃薯;若前茬使用阔草清(唑嘧磺草胺),每公顷用量有效成分48～60克,即80%阔草清(唑嘧磺草胺)每亩3.2～4克,需间隔12个月才能种马铃薯;若前茬使用氟磺胺草醚(虎威)每公顷用量有效成分375克,即25%氟磺胺草醚每亩100毫升,需间隔24个月才能种马铃薯;茬使用甲磺隆,每公顷使用有效成分超过7.5克,需间隔34个月才能种马铃薯;若前茬使用西玛津,每公顷使用有效成分超过2240克,即50%西码津每亩超过300克,需间隔24个月种才能马铃薯;若前茬使用莠去津,每公顷使用有效成分超过2000克,即38%莠去津每亩超过350毫升,需间隔24个月种才能马铃薯;若前茬使用绿磺隆,每公顷使用有效成分15克,需间隔24个月种才能马铃薯;若前茬使用二氯喹啉酸,每公顷使用有效成分106～177克,需间隔24个月才能种马铃薯.     

薇甘菊种子萌发对除草剂森草净的敏感性研究

通过敏感性测定,得出薇甘菊种子萌发时对除草剂森草净的敏感性极高,在质量浓度为10-7g/L(0.1ng/mL)下,就可以明显地抑制薇甘菊根的生长。相应地,薇甘菊的根生长被抑制其抑制率达50%时森草净的质量浓度为EC50=10-5.49g/L,抑制率为10%时森草净质量浓度为EC10=10-8.38g/L。     

紫外辐射诱导植物细胞DNA损伤的彗星检测

单细胞凝胶电泳(彗星检测)已广泛应用于动物细胞DNA损伤检测.该文报道了单细胞凝胶电泳应用于UV-B诱导植物细胞DNA损伤的检测.通过对动物细胞的单细胞凝胶电泳实验方法的改进,获得了在植物细胞中应用的最佳条件.以植物细胞原生质体为材料,并结合T4 Endonu lease V的运用,显著提高了UV-B诱导植物细胞DNA损伤提高彗星检测的敏感性和特异性.植物细胞DNA损伤的彗星图像经CASP软件处理并量化,结果表明:UV-A和UV-B均能诱导发生DNA单链断裂;UV-A在一定的剂量下诱导少量嘧啶二聚体的形成,而UV-B则强烈诱导嘧啶二聚体的产生.