A rapid method for screening barley for aluminium tolerance

Summary A method for rapid screening of large numbers of barley genotypes for aluminium tolerance is described, and the results of a small scale screening of composite cross CC XXX-C given.     

Nitrogen response models for winter cereals grown for forage

Forage double cropping can increase production, reduce erosion risk and improve soil health. Farmer experience in the north‐eastern USA shows that winter cereals can, in 3–4 weeks (Feekes 9 harvest), produce high quality forage given sufficient N at dormancy break. Here, we evaluate crop response models to determine the most economic rate of N (MERN) for forage winter cereals. Sixty‐three on‐farm N‐rate trials (0, 34, 67, 101, 135 kg N/ha) were conducted in New York from 2013 to 2016. Trials were divided into four categories: (a) no yield response to N (group 1; 20 trials); (b) yield plateau exceeded the highest N rate (group 2; one trial); (c) the MERN was below the lowest N rate (group 3; seven trials) and (d) all other N‐responsive trials (group 4; 35 trials). For group 4, three statistical models were compared (quadratic plateau, exponential and square root plateau). Statistical, environmental and economic criteria showed that the quadratic plateau fits the data best and had the most stable predictions across scenarios. The four‐category analysis is effective in determining MERNs of individual trials, and the quadratic plateau is best for determining forage winter cereal MERNs and yields at MERNs for individual trials in the north‐eastern USA.     

Method for screening bread wheat for tolerance to boron

A new method for screening wheat for boron tolerance has been developed to overcome the problems of methods used in the past. Seedlings were grown for 10 days while suspended over B-rich solutions. Their root lengths were then measured as an index of tolerance. Five varieties of wheat were screened at seven concentrations of B. Results were obtained more quickly and easily than from the alternative methodologies and compared favourably. Screening of 128 doubled haploid lines from a cross between Halberd and (Wl*MMC) suggested that transgressive segregation had occurred. This revised version was published online in August 2006 with corrections to the Cover Date.     

Contracting for Migration for the Reason of Zoological Environment

Migration for the reason of zoological environment is the measure for solving the crisis of zoological environment. Nowadays, governments play the chief role in the Migration for the reason of zoological environment, but the migration themselves do not have the freedom to decide whether migrate or not. Because the activity of migration is related to the restraint of economy, culture, law, etc. It is the object of migration that protect the zoological environment and improve the welfare of habitant, which must be concerned when constructing the systems of migration. This paper proves the possibility of contracting for migration based on the methodology of the cost-income analysis. On the other hand, it also argues for changing the mode of migration from that controlled by governments to being decided by habitant themselves.     

Genotype-environment relationships for repening time in blackberries and prospects for breeding an early ripening cultivar for Scotland

Summary When grown in Scotland, eight blackberry cultivars of diverse origin showed considerable variation in the dates when their first fruits ripened. These dates were determined in part by variation in the date of their first open flower and in part by variation in the number of days required from flowering to ripening. Genotype x environment interactions were important for both components, but especially for the second, where they could be attributed to heterogeneity of regressions against the environmental means. Temperature was considered the important environmental factor determining the number of days required from flowering to repening, and accumulated heat units successfully quantified the differences between cultivars for this component: cultivars required similar numbers of heat units in each season and there were no interaction effects. Heat units were not useful for study of flowering dates, however.The implications for breeding early ripening cultivars for Scotland are discussed.     

Assessment of techniques for screening alfalfa cultivars for aluminum tolerance

Screening toxicity tests are an effective method to characterize aluminum tolerant plants. In this paper, three screening procedures were used to assess aluminum tolerance among 13 cultivars of alfalfa (Medicago sativa L.). The procedures used were: Petri dish screening, black glass plot method and the soil-on-agar procedure. Major biological indices used to analyze aluminum tolerance were relative root length (RRL), relative germination rate (RGR), relative hypocotyl length (RHL), relative fresh weight (RFW) and root emergence (RE). Aluminum negatively affected all five indices. A Pearson correlation test indicated that the results of the three screening procedures were consistent, suggesting that all three could be used for screening purposes. However, because of the short test period and the simplicity of operation, the black glass plot method might be the best choice. Overall, cv. Super No. 7 and WL-525HQ were the most aluminum-tolerant alfalfa cultivars, while Pondus S was the most sensitive.     

A General Method for the Initial Values for Two-Sided Iteration

In the study on finding a group of inital values for solving operator equation x=G(x)by the two-sided iterative method,some stronger conditions forG(x)have been demandedand some new parameters have to be introduced since 1978,But,as it will be proved in this paper,Itis unnecessary to use any new parameters and other stronger conditions to get a group of initial val-ues of two-sided iterative, as those initial values can be obtained by means of an auxiliary iterativebeginning with operator G(x)itself. The numerical example in this paper illustraves that the methodproposed in this paper is a general method.     

Evidence for phenotypic assortative mating for flower colour in periwinkle

Two experiments were conducted with periwinkle, Catharanthus roseus, to determine the extent of natural outcrossing. Three white-flowered, fully self-fertile, monogenic recessive mutants, namely, dwarf, wavy leaf margin and curved leaf were used, together with their parental white-flowered variety, ‘Nirmal’, and a normal pink-flowered variety, PS-1. The extent of total outcrossing ranged from 43.4 to 79.3% among mutants. Outcrossing between white × white-flowered plants ranged from 28.3 to 65.3% and was two to four times greater than that between white × pink-flowered plants in the three mutants. The extent of out-crossing between white × pink-flowered plants was similar “02.2-15.0%” in all mutants and also similar to that in the normal white-flowered variety,‘Nirmal’(00.4%), where white × white flower out-crossing could not be estimated. There were no large differences in the number of seeds per fruit, percentage fruit set and germination percentage of seeds obtained from self, white × white and white × pink flower crosses made in the glasshouse. There were also no significant differences in the number of flowers produced by the genotypes used in the study. The observed higher frequency of white × white flower matings compared with white × pink flower matings appeared to be due to the constancy of flower colour exhibited by the butterfly pollinators Pachliopta hector and Catopsilia pyranthae during their flower visits. Observations made on the occurrence of natural self-pollination revealed that automatic self-pollination did not occur in periwinkle.     

农业植物品种权申请前的准备

一项能够取得品种权的植物新品种,必须同时具备以下几个条件:属于国家植物新品种保护名录范围;不违反国家法律、妨害公共利益或者破坏生态环境;必须具备新颖性、特异性、一致性和稳定性;应当具备适当的品种名称.另外,品种权是不能自动取得的,即使合乎授权条件的植物新品种,也必须履行<中华人民共和国植物新品种保护条例>(以下简称<条例>)和<中华人民共和国植物新品种保护条例实施细则>(以下简称<实施细则>)所规定的品种权申请程序.为了减少品种权申请的盲目性,节省品种权申请人和植物新品种保护办公室双方的人力、物力和财力,品种权申请人在提出申请以前一定要做好以下准备工作.     

Marker assisted recurrent selection for cumulating QTLs for bread-making related traits

We used a computer program to manage marker data in a recombinantinbred line population. The objective was to select pairs of inbred lines tobe intercrossed, in order to cumulate all favourable alleles, either withadditive effects or with interactive effects. The population size required tohave 95% chance of obtaining the best line from a given cross iscomputed, taking into account the number of QTLs and the probability thatno recombination event occurs in any QTL confidence intervals. It is shownthat the accuracy of QTL location greatly affects selection efficiency andthat a recurrent selection scheme is highly preferable for pyramiding manyQTLs. Dough strength (W) was chosen to illustrate the use of this method.In a population of 187 DH lines from the cross Courtot × Chinese Spring,W was found to be controlled by 8 additive QTLs and two pairs ofinteractive QTLs. None of the 187 DH lines possess all favourable allelesor combination of alleles. The best possible line could be produced by asingle cycle of crossing followed by line extraction, but several thousandlines needed to be produced to achieve this goal. Alternatively, a recurrentcrossing scheme allows to obtain the best line in two generations, andrequires less than 150 lines per cycle.     

索承式桥梁吊索钢丝腐蚀疲劳寿命评估

根据吊索镀锌钢丝腐蚀疲劳破坏特点,把镀锌钢丝腐蚀疲劳纹形成和扩展过程分解成镀锌层腐蚀失效、蚀坑萌生、蚀坑形成、短裂纹扩展、长裂纹扩展和断裂破坏等阶段,建立各阶段时间表达式,得到镀锌钢丝疲劳寿命表达式,提出基于断裂力学的吊索钢丝腐蚀疲劳寿命评估研究结果方法。通过算例分析复杂运营条件下腐蚀环境和应力幅等因素对吊索钢丝腐蚀疲劳寿命的影响,研究结果表明：吊索钢丝腐蚀疲劳寿命主要由钢丝镀锌层腐蚀、蚀坑发展和短裂纹扩展等3个阶段组成,为了准确地评估吊索腐蚀疲劳寿命,需要掌握大桥的运营环境和交通荷载。     

A novel procedure for raising rice seedlings and its potential application for mass-screening of rice strains for salt tolerance

Summary A soilless culture system is described whereby all the necessary steps of raising rice seedlings, including seeding, surface-sterilization, germination and growing of seedlings, can be conveniently achieved within a small plastic container. The system is especially suited for experiments with massive number of entries and can e.g. be used for screening of rice genotypes for salt tolerance.     

A Composite Index for Statistical Inference for Ranking Metropolitan Areas

ABSTRACT The construction of a composite index is described to rank U.S. metropolitan areas for educational attainment. The suggested methodology departs from traditional rank sum methods in that this approach utilizes data resulting in a continuous scale, whereas in the rank sum method, no use is made of the actual values of the data, but merely their rankings. The proposed index circumvents several practical problems because the numbers generated are metric measures allowing the use of arithmetic and statistical operations. Data used are pupil/teacher ratio, an effort index, and academic options in higher education. Comparisons are made across areas by population size and by geographic region.     

玉米制种缺素症（营养障碍）的防治

1　症状1.1　缺氮 :幼苗矮化 ,瘦弱 ,叶丛黄绿。生长株从叶尖开始变黄 ,沿叶片中脉发展 ,叶片上形成一个“V”形黄化部分 ,致全株黄化 ,后下部叶尖枯死且边缘呈黄绿色。缺氮严重或关键期缺氮 ,果穗小 ,顶部籽粒不充实 ,蛋白质含量低。1.2　缺磷 :嫩株敏感 ,植株矮化 ,叶尖、叶缘失绿呈紫红色 ,后叶端枯死或变成暗紫褐色。根系发达 ,雌穗受粉受阻 ,籽粒不充实 ,果穗少或歪曲。1.3　缺钾 :下部叶片的叶尖、叶缘呈黄色或似火红焦枯 ,后期植株易倒状 ,果穗小 ,顶部发育不良。1.4　缺钙 :植株矮 ,新叶生长受阻 ,新叶尖端几乎完全失绿 ,分泌透明…     

食用菌栽培料堆制诱发灭菌新方法探讨

将栽培料大量堆制,并控制适宜堆湿、堆温、翻堆和时间,诱使料中杂菌由休眠的孢子体转变为营养生长体,降低杂菌细胞对高温的忍耐力,再行一次短时常压灭菌,把料内杂菌一次杀灭.这样将灭菌过程分为诱发与杀灭二个阶段,这就构成了一种新的栽培料灭菌法——堆制诱发灭菌法.用之于生产,是解决目前平菇发菌阶段杂菌污染行之有效的措施.     

Optimization and Realization for Sinter and Ore Blending for Blast Furnace

In the ironmaking process, it is essential that sinter and feed of blast furnace are established economically and reasonably. Taking some steel company for example, the best economical condition for feed of blast furnace is comprehensively considered from technologic demand and economic efficiency. According to LP and based on practice and trial, aimed function and confined condition is confirmed, computation programs are made by Matlab while realizing optimization feed. The blast furnace material balance and heat balance are calculated by program with visual interface. Thus, we can directly judge rationality of optimization. The results show that LP is effective method to realize feed of blast furnace.