氮素营养水平对小麦后移栽棉氮代谢的影响

对不同氮素营养水平下的小麦后移栽棉叶片硝酸还原酶活性、棉株含氮量及叶片氨基酸含量等进行了测定。结果表明，除８月１９日外，叶片硝酸还原酶活性与施氮量呈极显著正相关（ｒ＝０．９６９３～０．９８８１）；地上部各器官的含氮率和绝对含氮量均随施氮量的增加而提高，且不同器官间呈同步增减的趋势，因而氮素分配比例的变化不大；提高氮素营养水平可显著增加小麦后移栽棉的叶片氨基酸总量和游离氨的含量（ｒ＝０．５３１６和０．５６０５），在１７种氨基酸中，谷氨酸、脯氨酸等７种氨基酸的含量与施氮量呈显著的正相关（ｒ＝０．５２５６～０．６０７４）。虽然施氮量越高，棉株的氮素代谢越旺盛，但小麦后移栽棉的适宜施氮量约为２０５ｋｇ／ｈｍ２。     

贫困地区农业技术推广新模式：发展小区域农业技术推广户 ——基于甘肃省部分贫困县的调查思考

（1甘肃农业大学经济管理学院，兰州 730070；2兰州资源环境职业技术学院，兰州 730020）     

“云大— 120 ”浸种对水稻秧苗素质及产量影响的研究

试验结果表明：用“云大— 120 ”浸稻种对种子的发芽势、发芽率、秧苗素质、有效穗和稻谷产量具有一定的促进作用，发芽势比对照提高 12.68% — 23.94% ；发芽率提高 3.75% — 18.75% ；有效穗提高 0.5% — 7.43% ；产量增加 1.03% — 8.49% 。其使用方法简单易行，在生产上具有重要的推广价值。     

Effects of Low- Intensity Ultrasound Treatment on Excess Sludge

In this study the influence of the low-intensity ultrasound treatment on excess sludge has been observed.The oxygen uptake rate(OUR),soluble chemical oxygen demand(SCOD),soluble total nitrogen(TN) and soluble total phosphorus(TP) were examined for three power levels of 0.03 W/mL, 0.05 W/mL and 0.1 W/mL as well as two time series of 0~5 min and 0~30 min.It showed that there were two stages of ultrasonic treatment: the first stage took place within the flocs in four minutes,in which SCOD,TN,TP were dissolved from flocs.In the second stage,the microbial activities have been strengthened,as well as OUR,TN,TP have increased greatly.     

植物新品种保护在企业科技进步中的作用

种子企业要在种子竞争中立于不败之地，就必须积极加快科研开发的步伐，全面启动品种创新，培育出更有竞争力的农作物新品种，才能使企业步入健康发展的轨道。同时对获得的植物新品种还应该认真加强保护，这样既保障了企业的应有权益，也激励了农业技术持续创新，规范了市场经济秩序，从而发挥知识产权为企业带来的经济效益，促使企业的科技进步。     

The Multiple Solutions for a Class of Quasilinear Elliptic Equations

A three critical point theorem is proved. As its applications, Dirichlet problem for a class of quasilinear elliptic equations cf second order is considered.