水稻超高产栽培条件下的适宜栽插期研究

以龙粳9号为供试品种,在肥力密度相同的条件下,设5个栽插时期处理,研究其对水稻生育和产量及产量构成因素的影响。结果表明,处理间的本田生育天数变化差异明显,但成熟期差异却只有1～2 d;不同处理的分蘖及成穗率、叶面积指数、抽穗至成熟期的干物质积累量和产量都呈现C>D>B>E>A的趋势。产量构成因素的各项指标以C,D,B较好,适宜栽插期范围为5月13日～27日。其中以处理C(5月20日)的产量(11 573.8 kg.hm-2)为最高,栽插时期最佳,其次是处理D(5月27日)和(B 5月13日)。     

不同杀鼠剂毒杀农田鼠类与家栖鼠类的药效观察

采用溴敌隆、氯敌鼠钠盐、杀鼠迷、灭鼠特4种杀鼠剂毒杀农田鼠类和家栖鼠类的试验结果表明，防治效果均以溴敌隆最高，防效分别达85．45％和88．58％，而且适口性明显优于其它杀鼠剂，可以作为贵州省大面积灭鼠的首选杀鼠剂。     

自动控制技术在节水灌溉中的应用

本文介绍了应用在节水灌溉领域中的自动控制技术,对它的类型和应用情况作了较详细的说明,并介绍了国内外的现状及发展趋势。     

珍珠梅花挥发物对小鼠旷场行为及学习记忆能力的影响

为了探讨珍珠梅花挥发物对环境的影响，该文采用动态顶空吸附法和热脱附-气质联用技术，分析了近自然状态下珍珠梅花的挥发物种类和相对含量；采用不同浓度珍珠梅鲜花对小鼠进行处理，分析了珍珠梅花挥发物对小鼠旷场行为及学习记忆能力的影响．结果表明:珍珠梅鲜花的挥发物对小鼠探索性、兴奋性、运动性有抑制作用；低浓度挥发物对小鼠的学习记忆能力无明显影响，高浓度挥发物抑制小鼠的学习记忆能力．珍珠梅鲜花的挥发物中，含氮化合物含量高，如三甲胺、1，1-二甲基脲、烟碱醛等，这些物质可能是对小鼠的旷场行为及学习记忆能力产生影响的主要原因．      

诸暨市古树资源调查研究

经全面调查,确定浙江省诸暨市有古树45 109株,隶属38科65属90种.其中树龄最大的为1 350 a,胸径最大2.95 m.提出了古树保护管理的6条建议.参3     

生长点点滴法在筛选鉴定转基因植株中的应用

对转化体 (种子或幼苗 )筛选的培养基筛选法和生长点点滴筛选法进行了比较分析。结果表明 ,在 4d苗龄的转化芥菜幼苗生长点点滴 80 0 mg/L 的潮霉素 ,获得了转基因植株 ,PCR检测结果表明 ,两种筛选方法的筛选结果一致。生长点点滴法的优点是 ,转基因幼苗不易污染 ,且成活率高。     

柠条种子害虫幼虫空间分布型及抽样技术研究

采用6种不同的判断空间分布格局的聚集度指标,并应用T ay lor幂法则和Iw ao回归分析法,得出柠条种子小蜂(B ruchophagus neocaraganae)、柠条豆象(Ky torh inus imm ix tus)、豆荚螟(E tiella z inckenella)3种柠条种子害虫的空间分布型为聚集分布,总结出田间调查抽样方法为分行取样法,并得出田间幼虫不同密度时的理论抽样数。     

紫花地丁抑菌活性成分的研究初报

采用活性跟踪法从紫花地丁的氯仿萃取物中分离得到1个抗菌活性成分(化合物1),并以停乳链球菌、金黄色葡萄球菌、大肠杆菌、无乳链球菌、乳房链球菌和沙门氏菌为供试菌,对紫花地丁的抑菌活性及其活性成分进行了初步研究。结果表明,化合物1初步鉴定为黄酮类化合物;紫花地丁的主要活性成分位于甲醇-水(V(甲醇)∶V(蒸馏水)=1∶1)萃取物和氯仿萃取物中;化合物1对以上6种供试菌的最小抑菌浓度依次为0.039,0.078,0.156,0.313,0.625和1.25mg/mL;对金黄色葡萄球菌、无乳链球菌和乳房链球菌的最小杀菌浓度≤2.5mg/mL,对停乳链球菌、沙门氏菌和大肠杆菌的最小杀菌浓度>2.5mg/mL。     

Effects of Zinc Deficiency and Drought on Plant Growth and Metabolism of Reactive Oxygen Species in Maize （Zea mays L.）

The combinative effects of applied zinc (Zn) and soil moisture on the plant growth, Zn uptake, and the metabolism of reactive oxygen species (ROS) in maize (Zea mays L.) plants were examined through two pot experiments under greenhouse conditions. Maize variety Zhongdan 9409 was used. In experiment 1, maize plants were grown in cumulic cinnamon soil with five Zn treatments (0, 3.0, 9.0, 27.0, and 81.0 mg Zn kg-1 soil). Three treatments of soil moisture including serious drought, mild drought, and adequate water supply were set at 30-35 %, 40-45 %, and 70-75 % (w/w) of soil saturated water content, respectively. Soil saturated water content was 36% (w/w). The dry matter weights of shoots were enhanced by Zn application and adequate water supply. There was no apparent difference in plant growth among Zn application rates from 3.0 to 81.0 mg Zn kg-1 soil. The increases of plant growth and Zn uptake due to Zn application were found more significant under well-watered condition than under drying condition. In experiment 2, two levels of Zn (0 and 5.0 mg Zn kg-1 soil) and soil moisture regimen (40-45 % and 70-75 % of soil saturated water content, respectively) were set. Zn deficiency or water stress resulted in higher concentrations of O2-· and malondiadehyde in the first fully expanded leaves.Zn deficiency lowered the activity of superoxide dismutase (SOD, EC 1.15.1.1) in leaves. Drought stress increased SOD activity in leaves regardless of Zn supply. The activity of guaiacol peroxidase (POD, EC1.11.1.11) was found to be enhanced by Zn supply only in well-watered leaves. Zinc deficiency or water stress had little effect on the activity of catalase (CAT, EC 1.11.1.6). The higher ROS level in early maize leaves due to water stress seemed not to be alleviated or lowered partially by Zn application. However, Zn fertilizer was recommended to apply to maize plants irrigated or supplied with adequate water, otherwise Zn deficiency would reduce the water use for plant biomass production.     

玉米抗丝黑穗病种质鉴定及遗传研究

丝黑穗病是我国玉米生产的重要病害之一。试验采用人工接种鉴定法研究黑龙江省常用玉米自交系和部分国内骨干系对丝黑穗病的抗性。在54份自交系中,鉴定出4份高抗系和8份抗病系,感病和高感系占64.9%。PB血缘材料中既有高抗材料,也有感或高感材料;含Mo17和自330血缘的材料多数抗或高抗玉米丝黑穗病,尤其是含Mo17血缘材料抗性更强;而含黄早四血缘的材料多高感玉米丝黑穗病;Ried血缘材料多属于中抗或感病类型。玉米对丝黑穗病的抗性遗传属核遗传,F1的发病率介于抗、感亲本之间,接近于双亲的平均值,不存在正反交差异。欲培育中抗以上类型杂交种,其双亲发病率应较低,杂交方式应为高抗×高抗;高抗×抗病;高抗×中抗;高抗×感病;抗病×抗病;抗病×中抗。