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31.
播期对花生光合性能与产量影响的研究   总被引:5,自引:0,他引:5  
以青花5号花生品种为材料,在田间地膜覆盖栽培条件下,系统研究了不同播期对花生光合性能和产量的影响。结果表明:不同播期对花生功能叶片光合性能和产量均有显著影响,叶面积系数、叶绿素SPAD值、净光合速率、产量均以4月30日和5月10日播种的较高,过早和过晚播种均不利于功能叶片光合性能和产量的提高。研究认为,在本试验条件下,5月上旬是花生获得高产的最佳播期。  相似文献   
32.
Two series of field trials were performed at three sites in Schleswig-Holstein between 1981 and 1988 to inquire into the yield structure of European winter types of Vicia faba L. and to compare their yield potential with that of spring types. Due to low winter survival, 6 winter types could be evaluated only in 4 environments in dependence of 1–3 sowing times (series α: seed rate 30/m2) and 1 winter type in 5 environments in dependence of 3 sowing times and 3 seed rates (series β: seed rate 15, 30, 45/m2). Seed yield of winter type averaged 410 g/m2 (D.M.) surpassing spring types by about 14 %. Environments caused a considerable variation in yield (275–620 g/m2) and in each yield component of winter types, while sowing dates and seed rates hardly affected the components seeds/pod and seed weight, which displayed stable genotypic rank orders. Compensative forces among the components plants/m2, tillers/plant and pods/tiller, were established. Plant densities of less than 10/m2 in spring, generally led to seed yield below 350 g/m2. Variation between 15–30 plants/m2 due to environments, sowing times or seed rates were frequently not fully compensated by tillering of plants, but often variation of the thus formed yield potential was reduced by pod set of tillers resulting in 210–270 pods/m2. The direction of correlations of pods/tillers with tillers/plant and plants/m2 differed due to experimental conditions whereas negative correlations between pods/tiller and tillers/ m2 were generally evident. Tillering was significantly influenced by the sowing time, though the increase because of early sowing was often covered by compensative effects of different plant densities. A genotypic capability to produce reproductive tillers was demonstrated using an approach which considered different plant densities and compensative forces. Neither a genotypic capability of tillers to set pods nor direct effects of environments or sowing time on pod set were established.  相似文献   
33.
PCR-ELISA法对大豆品种的转基因定性检测研究   总被引:4,自引:0,他引:4  
以共价交联在PCR管壁上的寡核苷酸作为固相引物进行PCR扩增,对PCR扩增的固相和液相产物分别进行杂交和凝胶电泳检测的PCR-ELISA法,对黑龙江省常规选育品种合丰35和黑农37、外源DNA直接导入大豆的分子育种所获品种黑生101、及大连进口的美国2号等大豆,进行转基因定性检测.结果表明:该方法高效可靠,可作为一种快速定性检测转基因产品的方法;检测结果:美国2号为转基因大豆,黑生101、合丰35和黑农37为非转基因大豆.上述结果对分子育种、生态保护、安全监测及对建立黑龙江省非转基因大豆生产保护区等具有重要意义.  相似文献   
34.
为了探索陕西高海拔地区黑麦草与苜蓿进行混播种植栽培条件,通过不同播种时间对黑麦草与苜蓿混播种植下生产性能的试验。结果表明:冬牧70黑麦品种的出苗时间、分蘖时间及返青时间等随着播种时间的延长而延长,其孕穗时间、抽穗时间、开花时间及刈割时间在8月中旬与9月中旬相一致,冬牧70黑麦品种的适宜播种时间以9-10月,9月下旬较好;甘农9号苜蓿的出苗时间、现蕾时间、初花时间及头茬刈割时间随着播种时间的延长而延长,适宜播种时间以9月下旬较好;冬牧70黑麦草在3个不同的播种期株高和株数存在极显著的差异(P<0.01),其倒伏率均为0%,在9月中旬种植的黑麦草产草量性状最优;甘农9号一茬与二茬苜蓿亩均鲜草量和亩均干草量在3个不同的播种期存在极显著的差异(P<0.01),在9月中旬种植的苜蓿产草量性状最优。重要试验结果为陕西高海拔地区黑麦草与苜蓿进行混播种植栽培技术,提高饲草的产量和质量具有重要的指导作用。  相似文献   
35.
典型高温年分期播种冬小麦生育及产量性状差异性分析   总被引:1,自引:0,他引:1  
在2016/2017年度自然高温年景下进行冬小麦分期播种实验,以适期晚播以来冬小麦多年平均播期(10月10日)为对照,设早播10d(E10)、迟播10d(L10)、迟播20d(L20)处理。通过方差分析、卡方检验、最小显著性差异和Logistic方程模拟等方法,对分期播种冬小麦发育期、生长量及产量因素等进行差异性分析,探究冬小麦在全球气候变暖背景下的适播期及其生长发育和产量性状变化规律。结果表明:不同播期处理的冬小麦冬前各发育期差异较大,越冬后随着气温升高,各播期冬小麦发育进程趋于一致;随着播期推迟,冬前积温递减趋势明显,冬小麦株高、绿叶面积和植株密度等生长要素均呈明显降低或减小趋势,冬小麦结实小穗数和不孕小穗数亦呈极显著减少趋势,各播期穗粒数则差异不显著;不同播期冬小麦千粒重差异极显著,其中早播10d处理极显著低于对照,迟播冬小麦处理与对照差异不显著;对照处理冬小麦产量最高;不同播期处理冬小麦灌浆过程均符合Logistic生长规律,对照籽粒渐增期持续时间长于其它处理,利于冬小麦增加籽粒“库容”,籽粒快增期灌浆速率快,利于提高粒重;随着播期的推迟,灌浆速率和持续时间的变化无明显规律,对照处理冬小麦灌浆过程相对稳定。  相似文献   
36.
燕麦与毛苕子混播试验初报   总被引:3,自引:0,他引:3  
通过对比试验的方法,进行了燕麦与毛苕子混播试验,结果表明:B处理鲜草产量明显高于其它处理,其抗倒伏性能随毛苕子播量的增加而降低。B处理的燕麦与毛苕子植株增高幅度也最大。  相似文献   
37.
The effects of variations in the relative sowing time of component crops in okra/maize and okra/cowpea intercropping systems were examined in 1990 and 1991 cropping seasons. Okra was either sown the same day as, or two weeks before or after maize or cowpea. Intercropping reduced the growth and yield of okra, maize and cowpea relative to their sole crops. However, okra yield was depressed more by maize than by cowpea, especially when okra was sown two weeks after maize. Comparative assessment of okra/maize and okra/cowpea mixtures suggests that it is better to grow okra and cowpea together than intercropping okra and maize because yield advantages were always higher in okra/cowpea (67% and 59% in 1990 and 1991 respectively) than in okra/maize (15% and 29%). The results were discussed in light of competitive abilities of the various components in the mixtures.  相似文献   
38.
This paper analyzes the industrial organization of public utility and its cause and synthetically researches government direct regulating pricing methods of public utility, mostly the static or dynamic cost mark-up pricing methods. It is indicated by the means of game theory and imperfect contract theory, under the conditions of imperfect information and the government's inferior position, It's impossible to develop the incentive mechanism to utility enterprise, makes low productivity in public utility. The inefficiency of the cost monitor and control is inevitable when the direct regulation pricing system be used. The thought of direct pricing methods is a mechanical obstruction to improve the effectiveness of public utility. It's the radical approach for the government to reform the regulation modes in order to improve the effectiveness and social surplus of public utility.  相似文献   
39.
Pearl millet ( Pennisetum glaucum L.R.Br.) hybrid MH 179 was grown under two moisture regimes viz., optimal moisture and rainfed conditions. The field experiment was continued for three consecutive rainy seasons to quantify the pearl millet development with thermal time. The possible influence of variation in natural sowing date on the relationships between crop development and thermal time have been described. At cardinal temperatures of 10°C (base temperature below which pearl millet development ceases), 33°C (optimal temperature for development) and 45°C (maximum temperature at and above which no development takes place), the crop required 1490–1794°Cd thermal time to reach physiological maturity. The thermal time requirement for different developmental stages was influenced by the sowing time and moisture availability during the growing season of the crop.
The leaf tip appearance on the main shoot of pearl millet in relation to thermal time was almost linear under both moisture conditions requiring about 44–50°Cd ± 2.6 °Cd leaf−1, till the appearance of the flag (last) leaf. However, leaf tip appearance on primary tillers was slightly slower and required 53-58°Cd ± 4.7°Cd for each new leaf. Appearance of first primary tiller was later (at 320°Cd after emergence) under the rainfed condition as compared to the crop under the optimal moisture (at 250°Cd).Thereafter, the tiller appearance in relation to thermal time under both moisture conditions was at a linear rate of about 53-56°Cd ± 9.5°Cd tiller−1.
Effect of microclimatic variations, canopy temperature, radiation and photoperiod on the phenology-thermal time relationships have been discussed under both the moisture conditions.  相似文献   
40.
A general approach to determine the effect of accuracy of sowing technique on yield per area
Caused by nonperfect seed placement accuracy of sowing machines as well as by many other abiotic and biotic factors the resulting plant stands exhibit nonregular plant distributions. Based on several simplifying assumptions a stochastic approach provides a quantitative determination of the effects of accuracy of sowing technique on yield per area. In this approach, two random variables are assigned to each individual plant: single plant yield E and single plant area A, which is calculated in this paper by the construction and quadrature of the so-called Thiessen-polygons. The yield per area F is calculated as the expectation of the ratio E/A. By assuming a deterministic mathematical relationship between E and A, the calculation of F reduces to the calculation of the expectation of a function of only one random variable A. A simple approximation with sufficient accuracy for many applications only depends on the mean and on the variance of the areas of the individual plants. For demonstration purposes, the theoretical approaches and results have been finally applied to three data sets for drilled seeds of winter oilseed rape (plant density: 60 plants/m2 and distance between rows: 10 cm). These data sets exhibit different accuracies of the longitudinal distributions within rows which have been quantitatively measured by the coefficient of variation for the distances between plants within rows: Yield depression increases with an increasing variability of plant distances within rows.  相似文献   
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