辣根过氧化物酶的分离制备和纯化

从辣根块茎分离和纯化了辣根过氧化物酶（ＨＲＰ）,纯化程度包括匀浆、加热、硫酸铵分级沉淀、丙酮分级沉淀和ＣＭ－２３阴离子交换层析。纯化的ＨＲＰ的Ｋ４值为２．５×１０＾５,ＲＺ值值３．００,酶的比活４０６Ｕ／ｍｇ蛋白。它的ＳＤＳ－ＰＡＧＥ显示一条带,酶亚基分子量为４０ＫＤ,等电聚焦电泳呈现三条带,酶不舔生染色呈现多条带,表明有同工酶存在。对酶的分离纯化作了一些改进,如加氨水保持ＰＨ值,加入５ｍｍｏｌ／     

应用球孢白僵菌防治芒果树脊胸天牛的研究

该文报导了从自然感病的脊胸天牛虫尸上分离出球孢白僵菌株,经纯化并批量生产可湿性菌粉,应用该菌粉防治芒果树脊胸天牛．室内试验用小棉花球醮取菌悬液堵塞法和用注射器抽取菌悬液滴注法接种,并分设对照组．第７ｄ检查防治效果．结果表明,堵塞法各虫态致僵、死率为７０．６％．其中幼虫僵、死率为８７．５％,蛹、成虫僵、死率为３６．７％．滴注法各虫态僵、死率为６６．１％．其中幼虫僵、死率为８２．５％,蛹、成虫僵、死率为３３．３％．对照组分别用无菌水以同样方法试验,各虫态致僵、死率均为０．应用两种方法,中试防治在１３．３ｈｍ２２７ａ树龄芒果园中进行,防治效果为８３．７％．推广应用防治在３５．０ｈｍ２１５ａ树龄芒果园中进行,防治效果为８４．１％．     

乌鳢腹水病病原的分离和鉴定

为了解乌鳢腹水病的发病原因,对患病鱼肝脏、肾脏、腹水进行了细菌分离和鉴定,并用分离菌株进行人工感染试验和药物体外抑菌试验,结果从病鱼体现人分离到形态和生理生化特性完全一致的６株菌,人工感洒试验证实均为腹水病原菌,经细菌学鉴定为费氏枸橼酸杆菌,体外抑菌试验表明,病原菌对环丙沙星、诺氟沙星、复方新诺明、卡那霉素高度敏感,可作为防治该病的首选药,研究证明,乌鳢腹水病的病原为费氏枸橼酸杆     

不同硬化地面类型对城市悬铃木物质循环的影响

研究了城市不同硬化地面类型（水泥地面、水泥砖面和踏实土地面）对悬铃木物质循环、水分循环及营养元素（Ｎ,Ｐ,Ｋ）循环的影响。结果表明：自然降水在城市水泥地面,水泥砖面或坚实的地表上很容易形成较大的地表径流,其中以水泥地面最甚,达４８％;各类型地面对雨水的渗透能力有明显差异,对照（花坛土）最强,为８７６％,踏实土（７２８％）次之,水泥砖面较差（３３％）,水泥地面渗透量接近于零。城市土壤营养元素除Ｋ外,Ｎ,Ｐ含量以踏实土最高,分别为００７７７和００８６６,其次为水泥砖面（００６９９和００５８７）及水泥地面（００５６２和００６３１）;生产力排序为：踏实土＞水泥砖面＞水泥地面。树木对土壤养分的吸收量也呈现相似的趋势,表现为：吸收量越大,理论归还量越大,但由于实际归还量较小,则土壤亏损就较多。     

MBTAE分光光度法测定微量锰

本文报道用2-(6-甲基-2-苯并噻唑偶氮)-5-二乙胺基酚(MBTAE)分光光度法测定微量锰。配合物的表观摩吸光系数为7.12×10~4L·mol~-1·cm~-1。MBTAE与Mn2 形成1∶2紫色配合物。配合物最大吸收波长为585nm。Mn2 浓度在0～8μg/25ml范围内符合比尔定律。方法用于人发中微量锰的测定,结果满意。     

四川盆地低山丘陵区森林承载力研究

本文以四川盆地低山丘陵区68个县森林资源现状为基础，探讨了森林承载力的概念，评价森林承载力的指标及提高森林承载力的途径。指出：森林承载力由森林生态系统物质产品的供应强度和非物质产品效能供应容量即环境负荷能力两个主要部分构成。通过合理调整农林结构，林种比例及树种配置，改善森林的内涵质等措施，显著地提高了森林承载力，使森林人口承载力和环境负荷能力由目前的超载转变为富余状况。     

第二代菜粉蝶自然种群生命表的研究

制作了第二代菜粉蝶ＰｉｅｒｉｓｒａｐａｅＬ．５年的自然种群生命表，求得了各年份的种群趋势指数，分别为１．２１、１．２７、２．９２、１．９７和１．８１；分析了其存活率曲线及类属于“Ｃ”型（Ｏ－ｄｕｍ，１９７８）。分析了影响菜粉蝶自然种群数量变动的关键因子，即蛹期被寄生性天敌寄生。应用Ｍｏｒｒｉｓ—Ｗａｔｔ模型，建立了菜粉蝶发生量预测式。     

N-硝基-N-(2,4,6-三氯苯基)-N′-2-甲氧基苯基脲生物活性的研究

研究了N -硝基 -N - ( 2 ,4,6—三氯苯基 ) -N′ - 2 -甲氧基苯基脲对单子叶作物水稻的植物生长调节活性及对单子叶杂草稗的除草活性 ,结果表明 :在一定的浓度范围内 ,该化合物对水稻具有植物生长调节活性 ,对稗具除草活性。     

氟化钠对雏鸡半数致死量的测定

为弄清氟对禽类的毒性影响,选用1日龄罗曼褐蛋鸡56只,随机分为7组,每组8只,经饮水添加不同量的氟化钠,1次性灌喂,观察7d内动物中毒死亡情况,计算LD50等指标。结果：急性LD50及其95％可信限分别为960．48mg／kg,594．72～1326．24mg／kg。结论：鸡对氟的耐受量较大,禽产品中氟残留量不容忽视,它可能危及人类健康。     

Potential for the alleviation of arsenic toxicity in paddy rice using amorphous iron-(hydr)oxide amendments

Abstract

A pot culture experiment was conducted to investigate the effects of amorphous iron-(hydr)oxide (Am-FeOH) amendments on arsenic (As) availability and its uptake by rice (Oryza sativa L. cv. BR28) irrigated with As-contaminated water. A rhizobag system was established using 3.5 L plastic pots, each containing one central compartment for plant growth, a middle compartment and an outside compartment. Three levels of laboratory-synthesized Am-FeOH (0, 0.1 and 0.5% w/w) were used to amend samples of the As-free sandy loam paddy soil placed into each compartment of the rhizobag system. The soils were submerged with a solution containing 5 mg L^?1 As(V). Two-week-old rice seedlings were planted in the central compartments and cultured for 9 weeks under greenhouse conditions. The addition of 0.1% Am-FeOH to the soil irrigated with As-contaminated water improved plant growth, reduced the As concentration in the plants and enhanced Fe-plaque formation on the root surfaces. Analysis of soil solution samples collected during the experiment revealed higher pH levels and lower redox potentials in the soils amended with Am-FeOH at the onset of soil submergence, but later the soil solution collected from the 0.1% Am-FeOH treatment was slightly acidic and more oxidized than the solution from the 0% treatment. This indicated active functioning of the roots in the soil treated with 0.1% Am-FeOH. The concentrations of As(III) in the soil solution collected from the central compartment were significantly reduced by the Am-FeOH amendments, whereas in the soil treated with 0% Fe, As(III) accumulated in the rhizosphere, particularly during the late-cultivation period. The improvement in plant growth and reduction in As uptake by plants growing in the Am-FeOH treated soil could be attributed to the reduction of available As in the soil solution, mainly as a result of the binding of As to the Fe-plaque on the root surfaces.