桃园梨小食心虫的发生与防治

1危害状 产在桃梢上的卵孵化后,幼虫从梢端第2-3片叶基部蛀入梢中,不久蛀孔流胶,并有虫粪排出,被害梢先端凋萎,最后干枯下垂。幼虫蛀入梢后,向下蛀食,当蛀到硬化部分时从梢中爬出,转梢危害,1头幼虫可危害2～3个新梢,幼虫老熟后在桃树枝干翘皮裂缝处作茧化蛹。     

苹果树生长期修剪技术要点

合理的生长期修剪,可以改善树体光照条件,缓和树势,促进花芽分化,同时减少树体养分消耗和冬季修剪量,达到早果丰产的目的。     

生物有机肥配施硅钾钙改良剂对酸性红壤梨园土壤肥力及产量的影响

[目的]为探究生物有机肥或配施硅钾钙改良剂对酸性红壤梨园土壤肥力和产量的影响,连续3季开展生物有机肥及其配施硅钾钙改良剂试验,研究梨园土壤养分含量、微生物量和土壤酶活性的变化,为酸性梨园土壤合理施用生物有机肥和改良剂提供理论依据.[方法]以当地习惯施肥为对照(CK),设置习惯施肥配施硅钾钙改良剂(CK+SOA)、仅施生...     

Concentration variations of several ions in stream after a wildfire

In May 2006, a high intensity wildfire occurred in Songling forest region in Daxing＇an Mountains, China. The concentration changes of eight ions （K^＋, Na^＋, Ca^2＋, Mg^2＋, Cl^-, Br^-, NO3^- and SO4^2-） were measured in burned and tmbumed streams after fire from May to Oct., 2006. Results show that the most ions flux were higher in burned stream than that in unburned stream during the sampling period, and the greatest concentrations of most ions transported from burned stream occurred in July. After fire, the most amplitude chemical ion was Ca^2＋, whose average concentration was 5.50 mg·L^-1 higher than that in unburned stream, and the total concentration of every chemical ion presents a trend Ca^2＋〉SO4^2- 〉Na^＋〉Mg^2＋〉NO3^- . The average concentrations of Ca^2＋, SO4^2- , Na^＋＇Mg^2＋,NO3^- showed an increase trend, but those of K^＋, Cl^- , Br had a decreased trend. SO4^2- had the largest loss among these anions, followed by NO3^-. Overall, the increase degree of cation was greater than that of anion after burning.     

常见杀虫剂对蟹栖拟阿脑虫的杀伤效果

蟹栖拟阿脑虫（Paranophrys careini Groliere＆Leglise,1977）,在生产中俗称纤毛虫,属纤毛动物门,寡膜纲,盾纤毛目,嗜污科（图见彩中插2）。虫体呈葵花籽形,前端尖,后端圆,大小为（28.1～62）微米×（9.2～21）微米,胞口位于前端腹面,有3片口膜。体表有11条纵纤毛线。体后端正中有1条长尾毛,     

一例鱼病治疗小结

2007年5月下旬,笔者接到盐城一养殖户的电话,称自己鱼塘里的鱼出现死亡。第二天笔者来到塘口进行现场了解,60亩鱼塘,主养银鲫,搭配花白鲢,当天死鱼100千克,主要是100克左右的银鲫。经检查水质老化,镜检有少量指环虫寄生,鳃红肿,肝胆有肿大现象,鱼体发黑,无出血。     

仔猪饲料添加黄芪的效果试验

为验证黄芪对提高仔猪生长性能、促进免疫机能的效果,选择100头健康断奶仔猪,分为5组,分别在饲料中添加黄芪1.0%、1.5%、2.0%、2.5%、0.0%,饲喂到64日龄。其间于36日龄免疫口蹄疫疫苗,免疫后第18、27天进行抗体检测。结果表明,仔猪饲料中添加黄芪能明显提高生长性能和免疫功能,其中2%添加量效果最为明显,考虑到经济效益,以1.5%的添加量较为合适。