剪切标志鲤科鱼类背鳍软条的组织学观察

对７种鲤科鱼类（草鱼、青鱼、鲢鱼、鳙鱼、团头鲂、鲤鱼、银鲫）采用剪断背鳍软条的方法作标志，约２个月后伤口处形成一节瘤状突起。根据组织学观察，瘤状突是一个坚硬的骨头，鱼经６１４天饲养，该标志性硬突不会消失。     

Some Problems in Solution of Intersection Points by Oblique Projection

This paper discusses several drawing problems as solution of intersection points and lines when a straight line intersects plane or conical surface, a plane intersects oblique pyramid and cylindroid and the axial line of normal cylinder has skew intersection with the axial line of cylindroid.     

Predicting anatomical maturity of Pinus sylvestris L. Seeds in northern Fennoscandia

The hypothesis tested was that it should be possible to predict maximum attainable level of anatomical maturity of Pinus sylvestris L. seeds, and thus the germination capacity, using only one x‐ray based sample value of anatomical potential (Ap) in combination with a time function. This sample should be taken after commencement and before cessation of embryo growth. Since this predictive model should be independent of temperature, it was validated by repeatedly collecting seeds from several localities with presumably different temperatures during ripening. Although the temperature sums differed between localities, the rate of increase in Ap was almost identical in August. According to multiple linear regression analysis, the highest coefficient of determination (0.81) was achieved if Ap values from collections made in August were used in the regression. The average absolute deviation for the different localities between actual and predicted maximum Ap was 2%, and the highest deviation 7.2%. Thus, it should be possible to make a good prediction of the maximum germination capacity as early as in August. The practical consequence of this is that cone collection and possible artificial ripening could be started very close to the optimal time. Furthermore, soil scarification could be done in seed tree stands before seedfall when high seed quality is predicted.     

紫外线诱变苜蓿愈伤组织抗旱性的研究

以苜蓿茎段为试材,紫外线诱变处理苜蓿愈伤组织。对诱变处理和对照的愈伤组织进行PEG干旱胁迫,并进行POD、可溶性蛋白和脯氨酸含量等抗旱性生理指标鉴定。结果表明:诱变处理3种生理指标趋于一致,均比未经处理的高。紫外线辐射的方法可以用于提高苜蓿抗旱性。     

60Co-γ射线辐照谷象不育剂量的研究

研究利用~(60)Co-γ射线辐照处理谷象成虫,得出雄性不育剂量为110Gy,雌性不育剂量为140Gy,并观察了辐照对成虫寿命、交尾率和交尾时间的影响。根据研究结果,提出释放不育谷象与被防治谷象的比例为50—100:1。     

红外线及微波处理番茄种子的生物效应

通过运用新红外线的生物效应，确定了最佳的红外线波长，功率密度和辐射时间，红外线峰波长乳白石英４－６μｍ功率密度为０．２Ｗ／ｃｍ＾２浸种１２ｈ辐射时间１２ｈ的番茄种子，既能提高高植株生长速度并增加其抗逆，又能使番茄植株早成熟５－７ｄ，增加座果率０．９％，产量显著增加。     

生产菌DAB啤酒酵母选育技术研究

生产性状发生退化的DAB酵母,采用30％致死率的紫外线处理,经高糖培养基筛选及单细胞分离等手段,得到一株性能优良的啤酒生产酵母菌种。     

X ray diffraction method of measuring microball coat thickness

Use of the X ray diffraction method to measure microball coat thickness is studied. A mathematical model of X ray diffraction of microballs is created and solved using computer aided simulation. The relationship between diffracted X ray intensity and coat thickness is calculated with the help of a standard sample possessing a known thickness. The coat thickness of other samples can be calculated by the intensity of diffracted X ray based on the same condition. The experimental result shows that this method is a rapid, convenient, non destructive means of measuring microball coat thickness.     

春黄菊族部分植物CYC2d同源基因的分离与功能初步分析

CYC同源基因作为控制花瓣对称性形成的关键基因,在菊科头状花序中主要调控着舌状花(两侧对称)的生长发育。菊科植物中舌状花的有或无及其分子调控机制和演化过程一直备受关注。本研究从花型不同的川甘亚菊、戈壁短舌菊和神农香菊中分别同源克隆了转录因子基因CYC2d。3个序列与菊花CmCYC2d基因氨基酸序列的比对结果显示其同源性均超过90%,且均含有保守的TCP和R结构域。半定量RT-qPCR结果显示,CYC2d在地被菊品种‘毛香玉’幼嫩花序中的表达量最高,而在川甘亚菊和戈壁短舌菊中的表达量非常微弱。因此,进一步通过实时荧光定量检测了CmCYC2d在‘毛香玉’6个发育时期舌状花和管状花中的表达情况,结果表明, CmCYC2d各个时期管状花中的表达量均很低,而在相应时期舌状花中的表达均很丰富。在不同花型的杂交F1代优株中,CmCYC2d也主要在不同位置的舌状花中高表达。通过农杆菌转化重组质粒pSUPER1300-CmCYC2d-GFP在烟草表皮细胞瞬时表达,亚细胞定位结果显示其定位于表皮细胞核。分别在野生型拟南芥和tcp1突变体(SALK-022364)中过表达CmCYC2d基因的结果表明,转基因阳性株系的营养生长受到抑制,花期延迟,花瓣大小和排列均发生了变化,使原本辐射对称的花瓣呈现两侧对称的趋势。从研究结果可知, 转录因子基因CmCYC2d对菊花舌状花的发育有重要调控作用。本研究为菊科舌状花演化的分子调控机制研究奠定了基础。