意大利蜜蜂近距离采蜜量与工蜂日龄的关系

在距蜂箱１０ ｍ 的地点放置质量浓度为０．７５ ｋｇ· Ｌ－ ３的蔗糖液，以测定各日龄意蜂的个体采蜜量．结果表明，采集蜂最小日龄为３ 日龄，１３～２７ 日龄段的工蜂采蜜量最高，每只蜜蜂每次采集６９．４４～７５．２５ ｍ ｇ；１２ 日龄以前的标记蜂采蜜量不稳定，随着日龄的增长逐渐趋于稳定；在测定地点，标记蜂１１ 日龄开始明显增多，直到２８ 日龄后减少．根据实验结果可以初步判定，近距离采集的适龄采蜜蜂为 １３～２７ 日龄．此项研究结果对蜜蜂饲养管理技术的改进有重要参考价值．     

白三叶草中绿原酸的提取及含量测定

采用70％的甲醇溶液为提取剂，索氏提取法对白三叶草中绿原酸进行提取，HPLC法对其中绿原酸进行检测。Luna C18柱（4．6nml×150mm，5μm），流动相为乙腈-0．4％磷酸溶液（体积比1：9），波长327nm，流速1．0mL／min。绿原酸在0．240～3．600μg呈良好线性关系，相关系数r为0．9996。结果表明白三叶草中含有绿原酸且含量较高。     

几种杀菌剂对南方红豆杉炭疽病的田间药效测定

在田间药效测定中,喷雾和注干两种施药方法相比,喷雾防治的效果明显好于注干的防治效果。喷雾试验中,防治效果最好的是甲基托布津,平均防治效果达到78.79%,最差的是退菌特,平均防治效果为57.20%;在注干防治试验中,防治效果最好的依然为甲基托布津,为62.50%,其次为炭克、多菌灵,最差的为退菌特,为46.57%。     

粮谷中丙线磷残留分析方法

对粮谷中丙线磷残留量的检测，采用新法以甲醇提取样品，经液液萃取净化后，再以气相色谱／氮磷检测器测定，测定低限为０．００５μg/ml的浓度范围内，标准曲线呈良好的线性关系γ＝０．９９６，变异系数为５．８％－７．８％，回收率为７２．０％－１００．２％。取代了常规法的繁锁操作程序，使操作步骤更加简便，分析速度快且灵敏度高，适用范围广。     

Characteristics of phosphorus uptake kinetics of poinsettia and marigold

In a previous experiment it has been found that maximum uptake rate (I_max), Michaelis constant (K_m), and minimum nutrient concentration (C_min) as plant physiological characteristics may be important for phosphorus (P) uptake in peat-substrate. Thus, variation of P uptake parameters was evaluated with a series of depletion studies for poinsettia (Euphorbia pulcherrima) and marigold (Tagetes patula) under fluctuating climatic conditions and different developmental stages.     

X射线无损检测技术在农产品品质评价中的应用

近年来,无损检测技术在农业中得到了广泛的应用.X射线检测作为无损检测的重要技术手段,在农产品品质检测与评价中发挥了重要的作用.为此,综述了国内外在X射线检测技术应用于农产品品质检测方面的研究进展;阐明了X射线检测技术测定的基本原理;介绍了其在果品水分测定、农产品内部病虫害检测、外观品质检测以及异物检测等方面的典型应用实例;并展望了X射线检测技术在农产品检测中的应用前景.     

吉林林区社会养老保障制度改革研究

在大量调查和深入分析的基础上，揭示了吉林林区现行社会养老保障制度存在的问题，论证了深入进行社会养老保障制度改革的必要性，提出了改革和完善吉林林区社会养老保障制度的措施     

FGF9调节性腺分化研究进展

性别决定过程是双潜能胚胎发育成睾丸或卵巢的过程.通过小鼠基因敲除试验以及在遗传水平分析性反转病人证明该过程是由多个基因调控的.论文综述了睾丸发育通路中信号分子成纤维细胞生长因子9(FGF9)在性腺分化中的作用.FGF9基因参与调节早期睾丸发育的3个重要事件,为调节性腺体腔上皮细胞增殖,促进Sertoli前体细胞形成,调节中肾细胞迁移,影响睾丸索的形成,FGF9诱导FGFR2在核内定位,并维持Sox9的表达.     

Age and growth of alfonsino Beryx splendens from the Kanto District, central Japan, based on growth increments on otoliths

ABSTRACT:   Age and growth of alfonsino Beryx splendens (Lowe) were studied using counts of presumed daily incremental growth rings on the transverse section of otoliths of fish collected from the Kanto District, central Japan. Microstructural growth increments were observed from the core to the outermost margin of the broadest of approximately 50 branches formed on the surface of an otolith. Of 98 otoliths examined, 46 were readable. The number of increments and fish lengths ranged from 448 (218 mm fork length [FL]) to 3701 (411 mm FL). The ages of these fish were estimated to be 1 year, 2 months and 10 years, 2 months, respectively, assuming that an increment was formed daily. The von Bertalanffy growth equation combined for males and females was expressed as follows: L _t  = 542 {1 −  exp  [−0.133( t  + 2.00)]}, where L _t is fork length (mm) at yearly age t . The results of the present study were compared with those of other researchers who had studied alfonsino from central Japan.