玉米自交系的空间诱变选育与应用

利用我国第二十颗返回式卫星搭载＂鲁原1423＂玉米自交系,并对其后代的主要性状进行了连续四代的调查分析。结果表明：SP1在出苗率及苗势上有明显的降低,播种后44 d的成活率仅有68.50%,从SP2代开始,随着世代的提高而增加;SP1代的株高、穗位高也普遍降低,在SP2代中出现了很高的变异株,变异范围明显大于对照;到SP4代时变异幅度已和对照接近,性状趋于稳定。处理后代的果穗性状会变劣,如出现果穗变短、变细、粒数减少的现象,后代株系果穗性状的变异范围基本上大于对照,这种现象在SP2、SP3代表现最为明显。SP3代的一些株系出现了不良的性状,如感染黑粉病、空秆、雄性不育,这对自交系的选育会有一定的影响。在杂交种的选育中,早代测配组合的平均产量虽然低于对照,但它们之间的性状差异很大,有可能产生优良的组合。卫星搭载会使玉米自交系的数量性状变化范围增大,变异类型增多,为育种增加了筛选机会,可以从中选育出综合性状优良的材料,＂航天7226＂系的利用就是证明。     

基于模态曲率改变率与神经网络的桥梁损伤识别

将模态曲率改变率和BP神经网络理论相结合,提出了桥梁结构损伤识别的新方法,据此识别结构损伤位置和损伤程度,并以一简支梁结构和一座连续梁桥为例进行了损伤识别.计算结果表明,该方法可以获得令人满意的识别精度.在结构参数化有限元模型存在误差的情况下,该方法仍然可以获得较好的识别效果,可应用于复杂桥梁结构体系的损伤识别.     

人工林毛白杨木材材色测定及其株间变异

测定了人工林毛白杨边心材的不同表色系统的色度学特征值,研究了毛白杨边材材色的株内变异情况。结果表明：毛白杨边材和心材及其不同板条的材色在ＸＹＺ空间,Ｌ＾＊ａ＾＊ｂ＾８色空间和孟塞尔色空间中,均有一定的分布范围,且不同板条的材色色度学参数在３个色空间中不完全相同,毛白杨边材材色是存在显著差异。     

尾叶桉材性指标在株内、株间和无性系间的变异性研究

以8年生尾叶桉(Eucalyptus urophylla S.T.Blake)无性系林为试材,就材性指标在株内、株间和无性系之间变异进行了研究分析。结果表明:纤维长度、纤维宽度、纤维长宽比、管孔弦向直径、纤维双壁厚度和纤维壁腔比在树干水平方向上的不同部位具有极显著性差异,呈由内向外逐渐增大的规律;微纤丝角度、单位面积管孔数和纤维腔径比在树于水平方向上的不同部位亦具有极显著性差异,但呈由内向外逐渐减小的规律;而木材胞壁率、木纤维比量、导管比量、射线比量、轴向薄壁组织比量和木纤维胞腔直径在树干水平方向上没有显著性变异;主要材性指标在同一无性系内的植株之间无显著性差异,但在无性系之间的差异均达到显著或极显著性水平。     

冬小麦品种抗、感白粉病性能变异动态研究

１９９３～１９９８年对河南省１３个主栽冬小麦品种白粉病的系统调查和抗性鉴定及评价结果表明：①河南主栽冬小麦品种中没有对白粉病免疫的品种,发病最重的是豫麦１３号,平均病指２８．９,平均ＡＵＤＰＣ值５０２;发病最轻的是郑州８３１,平均病指２．３,平均ＡＵＤＰＣ值２５。②感、抗白粉病性没有明显变异的品种占总数３８％,有明显变异的品种占６２％,其中,高感变中感的品种１个（西安８号）,中感变高感的品种１个（     

鱼鳞松自然类型的初步研究

本文对吉林省八家子林业局的鱼鳞松进行了调查,并按自然类型采集了枝叶、树皮及球果的标本,同时分类型作了树干解析。根据鱼鳞松树皮的开裂方式及粗细将鱼鳞松划分为两个自然类型,即:粗皮鱼鳞松(Picea jezoensis(Sien.et Zucc.)Carr.f.pachidelmis Wu et Du,f.nov.)和细皮鱼鳞松(Picea jezoensis(Sieh.et Zucc.)Carr.f.leptodermis Wu et Du,f.nov.),同时对二者的生长过程进行了比较和分析,为鱼鳞松类型的识别和鱼鳞松优良类型的选育提供科学的依据。     

Variations of Main Quality Components of Tea Genetic Resources [<Emphasis Type="Italic">Camellia sinensis</Emphasis> (L.) O. Kuntze] Preserved in the China National Germplasm Tea Repository

The variations of the main quality components of tea, tea polyphenols, catechins, amino acids, caffeine, and water extract of 596 accessions Chinese tea genetic resources, preserved in the China National Germplasm Tea Repository (CNGTR), were analyzed. Tea polyphenols content on a dry weight basis varied from 13.6 to 47.8%, averaging 28.4%.The tea polyphenols content increases gradually from northern and easternprovinces to southern provinces, the highest is in Yunnan tea resources.The content of catechins ranged from 81.9 g/kg to 262.7 g/kg, averaging 144.6 g/kg. The genetic resources from Hunan province had the highest catechins content, inconsistent with the tea polyphenols, which were highest in Yunnan tea resources. The amino acids content ranged from 1.1 to 6.5%, with an average of 3.3%. It was much lower in the southern provinces compared with northern and eastern provinces. The average caffeine content was 4.2%, varying from 1.2 to 5.9%. Yunnan province has plentiful high caffeine genetic resources, next is Fujian province. Caffeine content of Chinese and Japanese tea genetic resources were very similar.The average of water extract content was 44.7%, varying from 24.4 to 57.0%. The variation pattern was similar to that of tea polyphenols.Tea genetic resources of transnormal components are valuable and they could be used directly or indirectly for commercial functional components extract, breeding, and production.     

Phenotypic Diversity within a Collection of Distinct Okra (<Emphasis Type="Italic">Abelmoschus esculentus</Emphasis>) Cultivars Derived from Turkish Land Races

Ten traditional, Turkish okra cultivars (Bat? Trakya, Akköy 41, Kabakl? II, Denizli, Denizli uzun, Bornova (TR-57377 and TR-57420), Amasya Çiçek, Bal?kesir T-1, A?lasun/Burdur) and one commercial cultivar (Sultani/May Seed Company) were selected to represent the variability within domestic okra germplasm from the Anatolian Plateau. Replicated field trials were conducted to evaluate a total of 21 morphological, horticultural and physiological characteristics. Principal component (PC) analysis revealed that first two PC axes explained 49.66% of the total multivariate variation with the first six PC axes explaining 84.23%. The first PC axis separated number of locules, mature pod length and internode length, while the second PC axis separated pod yield/plant, pod number/plant, pedicel length and number of branches. All 21 characters were statistically significant among the cultivars and had at least one high coefficient in at least one of the first six PC axes, which demonstrated that all of them served as distinguishing characters among the cultivars. By using the unweighted pair-group method with arithmetic average four main clusters were consistently formed across all years. The four clusters were also related to the eco-geographic distribution of the cultivars. Each cluster members were also described for their main characteristics, which also provide useful criteria for further evaluation of okra germplasm across Turkey.     

ARIMA MODEL ON WOOD PROPERTIES VARIATION PATTERN OF KOREAN LARCH

INTRoDUCTIONItwasfOundthatthegoOdnssoffitwasnotgOodandthecOefficientofcorrelahonwaslowwhileuslngthemethodoflinearregressionanalysistoanalysesthewoodgrOwthnngvanahonpatternofPlantedLanxolgensis.ThewoodpowthringProPenieslnc1udesguwthringdenSty,grOWthringwidthandlatewoodpercentage.AslthewoodPrOpenies'parameters,mentionedasabove,thevariahont6ndencywassindlarwiththeresultsofPreviousresearch,butthedopeeofdjssociahonofadjacenttestpointswasbigrelahvely,andthevanahonten-dencywasinduencedbyran…     

香菇新菌株"庆科20"选育报告

以香菇主栽菌株"庆元9015"为母本,选出优良变异株"庆科20",该菌株具有独特的PCR扩增条带和蛋白电泳图谱,与"庆元9015"等菌株具有明显的遗传差异.该菌株春栽鲜菇单产比"庆元9015"和"241-4"分别增加7.7%和16.5%;秋栽鲜菇单产比"庆元9015"和"Cr02"分别增加3.3%和18.9%;花菇栽培平均单产比"135"增加20.7%.