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1.
超级稻“三定”栽培法研究Ⅰ 概念与理论依据 总被引:13,自引:1,他引:13
zouyingbin@.net 《中国农学通报》2006,22(5):158-158
(湖南农业大学农学院,长沙 410128) 相似文献
2.
超级稻“三定”栽培法研究I概念与理论依据 总被引:1,自引:0,他引:1
总结了国内关于水稻和超级稻高产栽培的基本生物学规律及其高产栽培技术研究的经验,提出了定目标产量、定群体指标、定技术规范的超级稻“三定”栽培法,并论述和讨论了“三定”栽培法的概念及其理论依据.指出超级稻品种有其适宜的种植区域,在不同生态区域种植的超级稻产量表现不同.生产上应按照超级稻的种植区域,以确定适合的栽培目标产量,采用与目标产量相一致的定量化栽培技术和群体发育调控技术,实现高产稳产高效的超级稻生产. 相似文献
3.
To research the influence of combustion chamber thermal boundary conditions on micro combustion characteristics in micro ICE, the laminar flow finite rate model is adopted to simulate the micro combustion process. Firstly, the influence of grid scale, the time step length and the maximum iterations per time step on accuracy of simulation results are explored. The results show that simulation results agree well with experimental results. And then, the influences of heat transfer coefficient, wall thickness and material on combustion characteristics are discussed. The results indicate that heat transfer coefficient has obvious influence on combustion characteristics. The pressure rise rate decreases, the ignition delays and the highest pressure value drops 2 atmospheres as heat transfer coefficient increases from 0 to 55 W/(m 2·K). The wall thickness and material have a little effect on combustion characteristics. This is because that the main heat transfer resistance in the heat flow path from cylinder to external environment lies between the outer wall and environment. 相似文献
4.
J. E. Lu´quez L. A. N. Aguirrezábal M. E. Agüero V. R. Pereyra 《Journal of Agronomy and Crop Science》2002,188(4):225-234
The best‐yielding and most stable cultivars are identified by growing cultivars in different environments. The stability of grain‐quality traits has been less thoroughly investigated than the stability of grain yield. High‐oleic hybrids of sunflower have been available on the Argentinian seed market for several years. Research on the stability of these genotypes is scarce. The objectives of this work were (i) to compare, using three different methods, the stability and adaptability of high‐oleic hybrids for grain yield and oil and oleic acid contents, and (ii) to explore the advantages and disadvantages of each method in selecting stable or adapted genotypes with high grain yield and high quality. Stability and adaptability analyses were performed on results for grain yields and oil and oleic acid contents of 35 high‐oleic sunflower hybrids from 17 comparative yield trials conducted over 2 years in Argentina. Stability was estimated using two methods: Fisher's protected least significant difference (LSD) test, which compared hybrids with the best‐yielding hybrid in each environment, and the test of relative yield (RY), which uses standard deviation as the measure of stability. Adaptability was estimated using Piepho's method of ‘multiple comparisons with the best’. These three methods can be applied to unbalanced data. Piepho's method made little discrimination amongst the hybrids. The LSD and RY tests coincided in classifying the hybrids as stable and unstable in 85 % of cases for grain yield and 76 % for oil content. It is concluded that the most convenient method depends on characteristics of the experimental design and of variability of the evaluated trait. Results from the LSD test depend on the number of environments in which the cultivar is tested. The RY method is valuable for classifying some cultivars as high‐yielding and stable, avoiding the problem of high‐yielding environments biasing the general average. Use of both methods together could be effective for classifying hybrids when the number of environments is adequate. 相似文献
5.
The study on the temperature evolutionary trend under both the ground stress and gas pressure is significant in the process of coal gas absorption and desorption. However, the valid signal is difficult to gain because of much noise in the experimental data, so according to the characteristics of the temperature signal gained under different experimental conditions of coal gas absorption and desorption, this essay filtrates noise and restores the valid signal by using the wavelet denoising of MATLAB to obtain the valid temperature evolutionary curve. Through contrasting and analyzing wavelet basis function and different decomposition levels, the essay chooses the sym8 wavelet basis function which has a higher order of vanishing moments and better smoothness. The reconstructed signal filtrates most of high frequency signal, and keep low frequency, as well as smooth signal. The result shows that the de-noising effect is good and the temperature evolution rule can be well reflected in the process of the coal gas absorption and desorption. 相似文献
6.
对北京地区小麦高产育种的看法 总被引:3,自引:0,他引:3
分析北京地区冬小麦高产育种的进展及问题,提出高产品种模式以中间型模式较现实可行,设计时应注意:1.对产量构成三因素要统筹兼顾,尽量挖潜,争取综合优势.2.协调穗粒数与抗寒及熟期的矛盾,在中等小穗数的基础上争取提高小穗结实数并力争减少不孕小穗数.3.穗粒重构成的三种类型,穗粒数/千粒重是:(1)中上/中上,稳产性好,较易实现;(2)中上/上,高产潜力大;(3)上/中,利于协调高产与优质.4.兼具中上等分蘖力,越冬抗寒性好及成穗率高,可获较高的亩穗数.5.株高80—85厘米,收获系数0.44—0.50为宜.多穗与大粒结合型,也可获得高产. 相似文献
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8.
The Recent Progress of the Slope Stability Analysis Methods 总被引:2,自引:0,他引:2
The slope stability is an important research content in rock mechanics. In recent years, the great achievement has been gained for the slope stability analysis methods. The deterministic analysis methods, including limit equilibrium theory, numerical analysis method, graphic method and compound method, have been developed. The stochastic analysis method and the fuzzy analysis method come forward. The recent progress of the slope stability analysis methods is analyzed in this paper. The trend of progress of the slope stability is studied. 相似文献
9.
Summary Thee groups consisting of 332, 243 and 280 barley breeding lines (entries) of known selection history were evaluated in 10, 9 and 8 environments, respectively, to determine the relationship between grain yield in low yielding (LYE) or high yielding (HYE) environment, and selection history and type of germplasm. One cycle of selection in LYE produced on average five times more entries outyielding the best check in LYE than selection in HYE. A retrospective analysis indicated that the highest yielding lines in LYE were lower yielding (15%–28%) in HYE when compared with the best check, and by 20% and 38% compared with the best entries in HYE. In contrast, the highest yielding lines in HYE were lower yielding (4%–33%) in LYE when compared with the best check, and by 33% and 40% when compared with the best entries in LYE. The highest yielding lines in LYE did not differ consistently from the highest yielding lines in HYE for a number of morphological and developmental traits including days to heading. This suggests there are many paths to high yield in LYE and that analytical breeding based on individual traits may not be appropriate for variable environments. Only 0.07% of the highest yielding entries in LYE was selected for high yield in HYE conditions confirming previous results indicating that selection for high yield in HYE is an inefficient strategy for improving yield in low yielding conditions. This frequency is 28 times lower than the frequency of high yielding entries in LYE selected from landraces or crosses with landraces in low yielding conditions. The results imply that the most cost-effective strategy for barley breeding in low yielding conditions is to select repeatedly in low yielding conditions and to include adapted germplasm (landraces) in the breeding material. 相似文献
10.
In order to investigate the effect on the performance of piston cam engine by the valve parameters, the instantaneous state analysis method is used to model the thermal process in cylinder and that is analyzed through computer simulation. The researching results indicate that the aperture of the air hole have little effect on performance of the piston cam engine when it is greater than a certain value; economy can be increased by decreasing intake angle on the premise of power need; power can be increased by decreasing the pressure of cylinder to back pressure at time of piston begin to get back; the forehead intake angle and compress angle for optimum power and economy can be get by comparing to different simulation results. 相似文献
11.
New types of precast concrete ribbed panels are developed in order to adapt to the complex loading conditions and different floor spans. Based on the yield line theory, equations for the ultimate bearing capacity and yield patterns of two-way composite slabs of different edge conditions and under uniformly distributed loading are developed, and the simplified formulas for the ultimate moment per unit width are proposed. The plastic limit analyses of two examples on the simple support and the fixed support are conducted, and the calculation results show good agreement with the experimental data. 相似文献
12.
以超高产春小麦品种克丰4号为试材,以新克旱9号、东农7742、克涝3号为对照品种,综合考察其独特的产量的结构及其干物质动态积累规律。试验结果统计分析表明:超高产品种克丰4号较其它三个品种具有明显的生物学特征特性,单株小麦的生物产量和粒重相对较低,但单位面积上群体的生物产量和粒重分别提高16.7%和48.2%。尤其以杆强和耐密成为具有当今高产产量潜力的主要因素。为今后东北春小麦超级种的组合配制、后代选择及高效栽培提供理论依据。 相似文献
13.
Seed yield is a major breeding target in tetraploid red clover. We investigated if marker‐assisted parentage analysis can identify progeny plants with two high seed‐yielding parents in tetraploid red clover and if this technique is more advantageous than traditional half‐sib selection. Parentage analysis was successfully performed on the progeny from the 10% highest seed‐yielding genotypes from a second‐cycle family selection trial: 16.0% of progeny were identified with a high seed‐yielding father. However, progeny plants with two high seed‐yielding parents did not produce more seeds than traditionally selected progeny (27.3 g vs. 30.7 g/plant, respectively). The 10% highest seed‐yielding genotypes displayed on average 2% self‐fertilization. Four genotypes were self‐fertile with individual selfing rates up to 20%. Our results discourage the use of marker‐assisted parentage analysis to improve seed yield in tetraploid red clover when the material has been preselected for seed yield. Breeders should be aware that intensive selection for seed yield in tetraploid red clover may inadvertently lead to selection for increased self‐fertility, which may increase inbreeding in the long term. 相似文献
14.
解淀粉芽孢杆菌(Bacillus amyloliquefaciens)12-7是从发病棉田土壤中分离得到的1株生防细菌,其对棉花黄萎病致病菌大丽轮枝菌Verticillium dahliae Kleb.V190具有明显的拮抗作用,已证明其抗菌物质为蛋白质。采用响应面法对该生防菌株的产抗菌蛋白条件进行优化,以期为棉花黄萎病生物农药的研制开发以及抗菌蛋白的后续研究奠定基础。以发酵液上清液对大丽轮枝菌的抑菌圈面积为考察指标,首先采用单因子试验考察培养时间、温度、初始pH、碳源、氮源、无机盐等因素对菌株12-7发酵产抗菌蛋白的影响;再根据响应面分析法的基本原理和方法,对发酵条件进行优化。得出该菌株产抗菌蛋白的最优发酵培养基和培养条件为:1.5%(质量分数)蔗糖、1.5%(质量分数)大豆蛋白胨、0.3%(质量分数)NaCl、0.1%(质量分数)K2HPO4、初始p H7.3的培养基,31℃发酵培养60 h。优化后抑菌圈面积从试验设计初期的171.95 mm2提高至320.3 mm2,且经过验证试验证实预测值与实际值之间具有较好的拟合度。 相似文献
15.
Physiological analysis of yielding ability in moth bean varieties under rainfed condition revealed that in spite of sufficient amount of dry matter production, the crop is a poor seed yielder. Late varieties produced higher amounts of dry matter and seed. The low yield in this crop is owing to low net assimilation rate (NAR) during the reproductive phase and poor migration coefficient of assimilates towards seeds. Leaf area expansion was maximum during reproductive phase. Stomatal components were not evident to limit the NAR under rainfed condition. Varietal differences were observed with respect to transpiration. Temporal variations in leaf water potential, osmotic potential and pressure potential were recorded. It is concluded that in moth bean the improvement in seed yield is possible by increasing current photosynthetic rate during the reproductive phase and can be achieved by changing the crop canopy structure for better utilization of light. Effort should also be made to improve harvest index in this crop. 相似文献
16.
晋麦63的评价与利用研究 总被引:1,自引:0,他引:1
在抗旱优质高产小麦新品种晋麦63的选育中,选用北部和黄淮两大麦区的优异种质,使目标性状得到了有效的组合,采用水旱交叉选育法,实现了自然选择、人工选择和定向培育的有机结合,提高了选种质量和效率。利用该品种进行广泛组配,获得其遗传特点为抗旱性、丰产性及综合农艺性状优,稳产适应性好,遗传传递力强,配组范围广,不良连锁基因易打破。利用其做亲本已选育出4个抗旱高产稳产广适小麦新品种,其中有3个品种同时通过国家审定。同时还育成了一批苗头品系和优异种质。实践表明:晋麦63不仅是一个优良的种植品种,而且是一个优异的亲本材料。 相似文献
17.
采用取样测数法和合并测产法分别对中双4号、华杂6号甘篮型油菜产量进行了测定。结果表明,合并测产法具有取样测数法获得油菜产量要素及理论产量的优点,且便于操作、减轻了工作量,工作效率高,与实收产量的符合程度高,精确度高,为2.1%,其结果准确可靠。 相似文献
18.
Summary Two-way classification analysis, combined with analysis of variance and linear regression techniques, was applied to a set of yield data from twenty-one genotypes grown at twelve locations for two years in International Mungbean Nursery trials. Genotypes and environments with similar yield response patterns were grouped and differences between groups identified. Genotypes were also grouped on the basis of flowering time and the relation between days to flower and yield was examined. It was concluded that cluster and associated analyses are of value in determining response patterns of mungbean genotypes to a wide range of environments, and a useful aid in the selection of materials and locations for mungbean evaluation. In particular we note the adaptation of genotypes M409 and M1134 to high elevation locations, and the positive yield response of M374 (MG50-10A) to high yielding environments. Highest yielding lines were also the earliest to flower. Disease resistance was considered the most important breeding objective for mungbean yield improvement. 相似文献
19.
Summary The causative sources of common variation of seven components of fodder yield in oats were analysed, using the centroid method of factor analysis. Two factors together accounted for most of the inter-correlations of these characters. Factor 1 had different degrees of positive loading on all characters, the highest being on the fodder yield. Factor 2 affected negatively a few and positively the remaining characters. The plant height and fodder yield were affected positively by Factor 1 and negatively by Factor 2. Factor 1 and 2 were significantly negatively associated with each other. The fodder yield components in the material studied seem to be influenced by the two interacting hormonal systems. The implications of the findings, in selecting for high quality and high yielding varieties of fodder oats, are discussed. 相似文献
20.
为了提高名优茶品质,发挥原料的最大经济价值,于1996—2003年在四川省农科院茶叶研究所实验场系统开展了不同名优茶形状对茶叶品质、生化成分及茶叶贮藏品质变化影响的研究。根据多年的试验研究结果,综合论述并提出了"名优茶品质的形态效应"新观点:名优茶品质不仅受茶树品种、生态环境、原料标准、栽培措施和加工技术等方面的影响,还明显受到加工的名优茶外形的影响。即:用相同原料制成的不同形状名优茶品质间差异较大,其中不揉捻或轻揉捻、叶组织破损小、工艺简单、热作用时间短的扁形或毛峰形名优茶的制茶工艺更有利于鲜叶原料品质的发挥和名优茶品质的形成。这在国内外首次把产品外形纳入茶叶品质的影响因素范畴,该观点的提出,对发挥原料的最大经济价值,提高茶叶品质和经济效益具有较大的生产指导意义和学术价值。 相似文献