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1.
T. McNeilly 《Euphytica》1982,31(1):237-239
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. 相似文献
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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. 相似文献
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Sarah E. Lyons Zhehan Tang James Booth Quirine M. Ketterings 《Journal of Agronomy and Crop Science》2019,205(2):248-261
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. 相似文献
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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. 相似文献
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ZHANG Zhi-liao 《保鲜与加工》2005,(8):149-153
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. 相似文献
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D. L. Jennings 《Euphytica》1979,28(3):747-750
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. 相似文献
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EDWARD NISSAN 《Growth and change》1994,25(4):411-426
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. 相似文献
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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… 相似文献
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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. 相似文献
10.
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. 相似文献
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Actin cytoskeleton plays an important role in cell morphogenesis in plants as demonstrated by pharmacological,biochemical,and genetic studies.The actin cytoskeleton may be involved in the transportation of organelles and vesicles carrying membranes and cell wall components to the site of cell growth as in root hairs,trichome cells,and pollen tubes.Actins in plants are encoded by a multigene family that comprises dozens or even hundreds of actin genes. 相似文献
18.
R. N. Kulkarni 《Plant Breeding》1999,118(6):561-564
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. 相似文献
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《棉花学报》2018,30(1):92-101
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