Applicability of Aegilops tauschii drought tolerance traits to breeding of hexaploid wheat     

Quahir Sohail  Tomoe Inoue  Hiroyuki Tanaka  Amin Elsadig Eltayeb  Yoshihiro Matsuoka  Hisashi Tsujimoto 《Breeding Science》2011,61(4):347-357

Few genes are available to develop drought-tolerant bread wheat (Triticum aestivum L.) cultivars. One way to enhance bread wheat’s genetic diversity would be to take advantage of the diversity of wild species by creating synthetic hexaploid wheat (SW) with the genomic constitution of bread wheat. In this study, we compared the expression of traits encoded at different ploidy levels and evaluated the applicability of Aegilops tauschii drought-related traits using 33 Ae. tauschii accessions along with their corresponding SW lines under well-watered and drought conditions. We found wide variation in Ae. tauschii, and even wider variation in the SW lines. Some SW lines were more drought-tolerant than the standard cultivar Cham 6. Aegilops tauschii from some regions gave better performing SW lines. The traits of Ae. tauschii were not significantly correlated with their corresponding SW lines, indicating that the traits expressed in wild diploid relatives of wheat may not predict the traits that will be expressed in SW lines derived from them. We suggest that, regardless of the adaptability and performance of the Ae. tauschii under drought, production of SW could probably result in genotypes with enhanced trait expression due to gene interactions, and that the traits of the synthetic should be evaluated in hexaploid level.  相似文献   

Applying hybrid dynamic substructure synthetic method to dynamic analysis for tower crane     

WANG Wei-ji  LIU Cheng-yi  ZHONG Wei  LI Zheng-liang 《保鲜与加工》2011,(8):114-120

This paper presents a dynamic hybrid substructure synthetic method for tower crane dynamic analysis. This method employs the transfer matrix method and the flexibility degree method respectively to formulate the vibration mathematical models of the tower body and tower top system substructures in the hoisting luffing plane. Based on the motion of the substructures in the interface and the dynamic harmonize condition, the frequency equations are established. Then the program is designed according to the mathematical models and firstly applied to the dynamic analysis of the QTZ63 tower crane in the construction site and the parameter identification of attached device and tower body. The test results show that the value calculated by the above method is quite approximate to the instrument measured value, which can meet the engineering requirements. Further study has found that , for the flexible long-distance attached tower crane, the method that introduces dynamic load coefficient for statics analysis of tower cranes is unprecise enough since there exist errors.This paper suggests to conduct site test and identification of the rigidity coefficient of attached device of the tower crane for the accident prevention of tower crane collapse by timely take measures.  相似文献   

造林模式效益评价的综合决策研究   总被引：5，自引：3，他引：5  

郑郁善  黄祖清 《福建林学院学报》1993,13(4):394-400

本文通过设置大量标准地,对不同造林模式(杉木、马尾松、杉松混交林、封山育林)的林分生物量、培肥土壤、水文效应、经济效益进行调查分析,应用大系统多目标综合决策层次分析法对多种造林模式进行定量评价,找出经济与生态效益最协调的造林模式,为荒山绿化中期效果定量评价方法和指标提供科学依据。  相似文献   

多种病虫综合危害小麦产量损失率及综合防治指标的研究   总被引：1，自引：0，他引：1  

迟新之  原永兰 《山东农业大学学报(自然科学版)》1995,26(4):471-479

通过田间开放式小区试验研究，明确了小麦穗期多病虫同时危害与产量损失的关系：建立了小麦穗期受麦蚜Ｘ１、白粉病Ｘ２和叶锈病Ｘ３同时危害与产量损失的相关模式。设立了麦蚜Ｘ１、白粉病Ｘ２的经济阈值模型。并提出了稳期病虫的综合防治指标。  相似文献   

奶牛线性外貌Fuuzy综合评判方法的研究     

刘小军  黄应祥  白金枝 《山西农业大学学报(自然科学版)》1996,(1)

本研究拟合了将线性评分转换为百分隶属度功能分的最优回归方程，采用Ｆｕｕｚｙ广义综合评判决策模型，确定了综合评判奶牛体型的模糊数学模型和计算机程序，其中各性状的权重分配用灰色关联度分析法研制。用此法对部分实测奶牛做的计算结果表明，该数学模型本身具有较高的灵敏度，评判结果与实际情况相符。  相似文献   

冷锋云系的多普勒雷达反射率因子特征总结     

赵广娜  石慕真 《安徽农业科学》2011,39(31):19435-19437,19470

[目的]总结冷锋云系的多普勒雷达反射率因子特征。[方法]从反射率因子特征上来研究冷锋云系,利用2002～2007年哈尔滨新一代天气雷达资料,总结了冷锋云系的反射率因子特征。[结果]冷锋所产生的云总体上说呈带状,但其间云体有间隙,且强度分布不均匀;多数移动快的冷锋为长而窄的回波带,移动缓慢的冷锋或弱冷锋,则呈宽广的片状或片絮状回波;面积大的冷锋云系通过测站基本都可以分析出径向速度由西北风转为西南风;随着月份的不同,反射率因子特征也有很大的变化。在冬季,冷锋云表现为层状云,反射率因子特征非常弱,一般面积较大,呈片状,但结构松散,回波间有间隙,其中夹杂着几块比较强的回波;在冷锋两侧易产生强度大的对流单体回波,一般会随着整体云带移动,移速、移向基本一致;干冷锋移过时,易局地产生强对流,以对流云为主,回波面积较小,一般从径向速度图中分析不出风向转变,但单体的强度特征明显,一般有＂三体散射＂、＂旁瓣＂、＂弱回波区＂特征,具有超级单体的特征。[结论]该研究为多普勒雷达在黑龙江省监测灾害天气的应用上起到了积极作用。  相似文献   

利用SSR标记分析"川育12"和人工合成小麦"SYN780"的遗传差异     

曾云超  李俊  杨玉敏  廖杰  魏会廷  彭正松  杨武云 《西南农业学报》2007,20(2):296-299

四川育成品种“川育12”和CIMMYT硬粒小麦-节节麦人工合成种“SYN780”都具有优质小麦基因,本试验利用小麦A、B和D基因组上的229对引物对“川育12”和“SYN780”进行了SSR分子标记比较分析。结果表明,229个SSR标记位点中有140个位点“川育12”和“SYN780”存在多态性差异,占位点数的61.1%。这140个差异位点在A、B和D3个基因组的分布频率(占该基因组被检测位点数)不一致,其中B基因组分布最多,D基因组分布最少,其顺序为B(64.2%)>A(63.5%)>D(54.9%)。  相似文献   

水稻对田间多种病虫害综合抗性的评价初探     

计仁欢  蓝启和  刘婵媛  郭莉  凌远生 《勤云标准版测试》2008,(8)

 通过对柳江县近年引进、推广的中优663等13个主要水稻品种（组合）进行田间小区试验,采用[0,1]多目标决策法进行综合评价,按对稻飞虱、稻纵卷叶螟、三化螟及稻纹枯病等多种病虫害的综合抗性的强弱排序为：优Ⅰ602＞金优602＞灵优6602＞丰两优1号＞金两优2号＞优Ⅰ402＞T优259＞金优463＞中优71＞中优663＞中优207＞金优207＞金优616。前五个品种（组合）均为中抗,其余品种（组合）均为中感。无高抗品种（组合）,说明水稻对多种病虫害的综合抗性的选育工作任重而道远。通过亲缘关系分析发现,亲缘关系相近的水稻品种（组合）具有相近的综合抗性;分析五个中抗品种（组合）的抗性构成,为不同生态环境的品种布局提供依据。  相似文献   

利用人工合成六倍体小麦育成的新品种"川麦42"的生态适应性及产量潜力研究     

汤永禄  朱华忠  李朝苏  黄钢  余秀芳  陈放  杨武云 《西南农业学报》2007,20(2):275-280

川麦42是利用CIMMYT人工合成六倍体小麦新资源育成的超高产新品种。2004~2006年,在四川多个生态点将川麦42与7个小麦品种的相关特性进行了比较研究。结果表明:①川麦42的丰产潜力较高,籽粒单产一般可达6~8 t/hm2,平均比其他品种高7%~15%。在各生态点间的变异系数较高,达到20%~25%。②川麦42因产量高,其需肥量较大,一般高氮处理的籽粒单产都显著高于低氮处理。同时,中等密度(220~240苗/m2)有利于高产。③因春性较强,不宜过早播种,以10月25~30日为最佳播种期。④川麦42中后期灌浆速率高,优势明显,利于发挥大粒大穗潜力。  相似文献   

Growth and Eco-Physiological Performance of Cotton Under Water Stress Conditions   总被引：1，自引：0，他引：1  

WANG Chun-yan Isoda Akihiro LI Mao-song WANG Dao-long 《中国农业科学(英文版)》2007,6(8):949-955

A cotton cultivar Xinluzao 8 was grown under four levels of water stress treatments （normal irrigation, slight, mild and severe water stress） from the initial reproductive growth stage in Shihezi, Xinjiang, China, in 2002, to evaluate the growth and eco-physiological performances. Under water stress conditions, the transpiration ability decreased while the leaf temperature increased. Although the relative leaf water content decreased as water stress increased, the differences among the treatments were small, indicating that cotton has high ability in maintaining water in leaf. The stomatal density increased as water stress increased, while the maximum stomatal aperture reduced only in the severest stressed plants. The time of the maximum stomatal aperture was delayed in the mild and severe stressed plants. When severe stress occurred, the stomata were kept open until the transpiration decreased to nearly zero, suggesting that the stomata might not be the main factor in adjusting transpiration in cotton. Cotton plant has high adaptation ability to water stress conditions because of decrease in both stomatal conductance and hydraulic conductance from soil-to-leaf pathway. The actual quantum yield of photosystem Ⅱ （PS Ⅱ） decreased under water stress conditions, while the maximum quantum yield of PS Ⅱ did not vary among treatments, suggesting that PS II would not be damaged by water stress. The total dry weight reduced as water stress increased.  相似文献