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向日葵下胚轴体细胞胚发生的基因型效应 总被引:3,自引:1,他引:2
采用3因素3水平的正交试验L9(34),研究了种植密度、施肥量、单株有效穗保留数量对蓖麻新品系6052产量的影响。结果表明:种植密度、施肥量对蓖麻产量的影响均达到极显著水平,单株有效穗保留数量对蓖麻产量无显著影响。最佳栽培技术方案:种植密度12 495穴/hm2,行塘距为1.0m×0.8m;施底肥钙镁磷肥375kg/hm2,并在植株有6~8片真叶及主穗现蕾时,各追施尿素75kg/hm2;单株有效穗数保留6穗。 相似文献
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山东省审定大豆品种的产量、品质及株型演变 总被引:4,自引:0,他引:4
自1982年开展农作物品种审定工作以来,山东省共有50个大豆品种通过国家或省级审定。本文分析了这50个审(认)定品种的区域试验平均产量、最高产量、蛋白质含量、脂肪含量和生育期、株高、主茎节数、有效分枝数、单株荚数、百粒重等农艺性状。结果表明,区域试验平均产量由1982-1985年的1892.73 kg/hm2提高到2001-2005年的2820.67 kg/hm2,增幅为49.0%;最高产量由3072.0kg/hm2提高到4389.3kg/hm2,提高了42.9%;蛋白质和脂肪含量随时代和选育目的的不同而在37.00%~46.44%和16.80%~22.50%之间变化。山东省夏大豆的理想株型应是株高70~80cm,主茎节数14~16节,有效分枝1~2个,并且在此基础上,有密而均匀的结荚。 相似文献
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Field experiments were set up from 2001 to 2004 in North West Italy to determine the effects of plant density on the susceptibility of medium and medium-late maturity maize hybrids to ear rot and to mycotoxin contamination in natural infection conditions. The ears were rated for the incidence and severity of disease symptoms at harvest and the harvested kernels were analysed for mycotoxin fumonisin B1, zearalenone, deoxynivalenol, aflatoxin B1 and ochratoxin A. 相似文献
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To ascertain the reasons for the high plant mortality in fibre-hemp (Cannabis sativa L.) crops in the Netherlands changes in biomass yield, plant mortality and plant morphology were investigated in a hemp cultivar grown at initial densities of 10, 30, 90 and 270 plants m−2. At 90 plants m−2 this cultivar was compared with a high bast-fibre cultivar and a late-flowering cultivar. Rate of canopy establishment and early growth rate increased with increasing plant density. At 90 and 270 plants m−2, plants died as a result of self-thinning. Self-thinning was associated with a reduced crop growth rate. In self-thinning stands, dry biomass (B, g m−2) was related to density of surviving plants (D, m−2) as log B = 3.81 − 0.304 log D. At the same crop growth rate, the rate at which plants died from self-thinning was higher in hemp than in other herbaceous dicots. The proportion of stem in the total dry matter increased with increasing plant density. Stem yield was maximum at 90 plants m−2. Stem quality improved with increasing density as the bark content in the stem increased, but self-thinning reduced the bark content in the stem. Optimum plant density was close to that resulting after self-thinning. In hemp the relationship between yield and optimum plant density is approximated by the equation of its self-thinning line. The late-flowering cultivar yielded more than the other two cultivars because it grew faster during the latter part of the growing season. 相似文献
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As the most important cultural practices for cotton production, the single effects of plant density and [nitrogen (N) and potassium (K)] fertilization on yield and yield components are well documented but their combined effects on Bt cotton are poorly understood. Using a split–split plot design with four replications, we conducted a two-year field experiment in two fields, one with lower fertility and the other with higher fertility, in the Yellow River Valley of China. The aim was to evaluate both the individual and combined effects of plant density and nitrogen and potassium fertilization on yield, yield components and uptake of major nutrients. The main plots were assigned to plant density (4.5 and 7.5 plants/m2), while nitrogen (0 and 240 kg N/ha) and potassium fertilization (0 and 150 kg K/ha) were assigned to the sub- and sub–subplots. Lint yield was improved with high plant density (7.5 plants/m2) in the lower fertility field, particularly without N and K application, but not in the higher fertility field. Nitrogen or K application also increased lint yield, and a combination of high plant density, N and K application further improved lint yield in the lower fertility field, while only K application increased lint yield in the higher fertility field. Lint percentage was not affected by any of the variables studied. Thus, the yield increase due to plant density, fertilization or their combinations was attributed to increases in boll number or boll weight. The ratio of seed cotton to stalk (RSS) was linearly correlated with harvest index, and thus can be a simple indicator of dry matter allocation to reproductive structures. Increased yield due to plant density and fertilization was mainly attributed to the enhanced biological yield in the lower fertility field, while the yield increase due to K fertilization was mainly due to increased RSS in the higher fertility field. The plants used approximately equal N and P to produce 100 kg lint in both fields, but the uptake of K to produce 100 kg lint in the higher fertility field was about 21% more than that in the lower fertility field. Ratios of N:P:K were 1:0.159:0.604 in the lower fertility field and 1:0.159:0.734 in higher fertility field. This study suggests that K fertilization was extremely important for maintaining high yield, although luxury consumption occurred in the higher fertility field; N was applied more than required in the highly fertile field, and increased plant density would be beneficial to cotton yield in the lower fertility field. 相似文献
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L. Echarte A. Della MaggioraD. Cerrudo V.H. GonzalezP. Abbate A. CerrudoV.O. Sadras P. Calviño 《Field Crops Research》2011,121(3):423-429
Maize-soybean and sunflower-soybean intercrops have the potential for increasing yield per unit land area and time in fully mechanized farming systems. The objectives of this work were to measure the land equivalent ratio index of maize and sunflower intercropped to soybean, to assess the effects of plant density of its components, and to gain insight into ecophysiological processes affecting their yield determination. Maize-soybean and sunflower-soybean intercrops and their respective sole crops were grown at Balcarce, Argentina during two growing seasons. Treatments included a wide range of plant densities for sole and intercropped sunflower (2-9 plants m−2) and maize (4-12 plants m−2). Plants were harvested to determine shoot dry matter and grain yield per plot and at the individual plant level. Land equivalent ratio index (LER) increased 11% (mean of the two years) when plant density of sunflower was reduced from 6 to 3 plants m−2; and LER increased 5% (year 1) or it was maintained (year 2) when maize plant density was reduced from 8 to 4 plants m−2. Yield response to plant density of sunflower and maize influenced LER. The response to plant density of intercropped sunflower and maize grain yield followed the same pattern than that in a sole crop, and grain yield of intercropped sunflower or maize were lower than those for the sole crops at each plant density except at the lowest sunflower plant density. Yield reductions from sole crop to intercrop at each plant density averaged 20% and were associated (i) with lower intra-row spacing in the intercrop and (ii) with a lower shoot production rather than to a change in the dry matter partitioning to reproductive structures; in addition, detrimental effects of soybean over maize or sunflower yield were undetectable. 相似文献
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栽培措施对直播油菜冬前生物学性状及产量的影响 总被引:13,自引:2,他引:13
采用三元二次回归旋转组合设计,研究油菜直播栽培方式下,栽培密度、施氮量、施磷量与冬前植株各形态、生理指标及产量之间的关系,获得了产量高于3 000kg/hm2的优化农艺措施方案,以及冬前各形态、生理指标与产量之间的关系. 相似文献
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栽培密度对高油大豆籽粒产量及品质影响初探 总被引:21,自引:2,他引:21
栽培密度对大豆产量和品质性状影响的研究结果表明,生物重和籽粒重在不同密度间均存在在显著差异,蛋白质和脂肪含量在不同的栽培密度下有一定程度的差异,但未达到显著水平。籽粒重随密度(在供试的密度范围内)的增加而提高。在14.5万株/hm^2栽培时,生物重达最高,籽粒重和脂肪含量在15.75万株/hm^2时达最高,蛋白质含量在12.25万株/hm^2栽培时达最高。 相似文献
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精播麦套花生套期、肥料与密度优化配置 总被引:7,自引:1,他引:7
大田条件下采用二次饱和D—最优设计建立了精播麦套花生套期、密度和N肥与产量的数学模型。分析表明: (1)套期与密度、密度与肥料间呈负向交互效应。套期晚,花生适宜密度应相应增加;密度增加,N肥用量可适当减少。套期与肥料呈正向交互效应,套期早, N 肥用量也应适当增加。( 2) 麦套花生最高产量可达到5 795. 4kg/hm2 ,相应的措施组合为:麦收前22d套种,每公顷播20. 7万株,施N 89. 3kg。产量在4 500~5 250kg/hm2 范围内的措施组合为:麦收前18~29d套种,每公顷播18. 8~22. 2万株,施N 49. 4~90. 7kg;产量在5 250~5 795kg/hm2范围内的措施组合为:麦收前17~22d套种,每公顷播18. 9~22. 7万株,施N 72. 7~108. 9kg。(3)夏直播花生最高产量可达到4 873. 0kg/hm2 ,相应的措施组合为:每公顷播20. 8万株,施N 85. 4 kg/hm2。 相似文献
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In the Mediterranean farming systems of the Western Australian wheatbelt, crop yields are influenced primarily by the amount and distribution of rainfall and the soil's capacity to hold moisture. The wheatbelt's growing season rainfall varies in the range of 200–400 mm (average) and the plant available water holding capacity (PAWC) of soils is generally in the 40–140 mm range. The grain yield of wheat is sensitive to this combination of small rainfall and small storage capacity.In this study, we explore the relationship between yield and PAWC using a combination of simulation modelling and analysis of field data. Crop yields and soil properties were monitored in detail at 17 locations (PAWCs 43–131 mm) across six seasons (1997–2005). Crop yields were also simulated using the APSIM crop simulator (RMSE = 311 kg/ha) to evaluate the long-term relationship between crop yield and plant available water capacity using 106 years of historical climate data.The relationship between crop yield and PAWC varied with season, and two important factors emerged: (1) for PAWC < 65 mm, there was a linear relationship with crop yields that ranged from 17 kg/ha/mm to 58 kg/ha/mm of PAWC across seasons; (2) for PAWC 65–131 mm the crop yield response to PAWC ranged from 11.5 kg/ha/mm in 45% of seasons to no response.The impact of PAWC on crop yield was reduced in seasons with late rainfall, and magnified in seasons with reduced rainfall late in the growing season. Six distinct season types with different yield–PAWC relationships are identified and season-specific management strategies that exploit within-field variation in PAWC are developed to manage the spatial variation of PAWC in a field. 相似文献
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油菜高产群体质量指标研究 总被引:17,自引:0,他引:17
通过测定油菜不同群体干物质积累动态、群体光合面积的变化以及交替、结角层中角果的空间分布等,研究了油菜高产群体的质量指标.其主要结果如下:(1)油菜初花之前形成的生物产量与籽粒产量呈二次曲线关系,而终花期和成熟期的生物产量与籽粒产量呈直线关系.说明越到后期形成的生物产量与籽粒产量的关系越密切.(2)油菜最大叶面积指数(LAI)和角果皮面积指数(PAI)与最终籽粒产量均呈二次曲线关系,其最适范围为4~4.5.(3)油菜群体总茎枝数及各次茎枝的配比与群体质量密切相关,高产群体适宜的总茎枝数为2.7~3×106/hm2,其中主茎9.75~11.25×104/hm2、一次分枝1.2~1.35×106/hm2、二次分枝1.35~1.5×106/hm2.(4)油菜各枝序的生产力与其在结角层中的位置有关,高效分枝的结角起点应在主序之上,结角终点则不低于主序10~15cm. 相似文献
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土壤压实胁迫对烟草前期生长的影响初报 总被引:1,自引:0,他引:1
为分析研究土壤压实胁迫对烟草前期生长的影响,以红花大金元烟草为研究对象,开展了不同土壤压实度盆栽试验,结果表明:烟草品种红花大金元适宜生长的土壤压实范围介于1.1~1.3 g/cm3;对于地下根系,压实主要影响根系的纵向生长;对茎围影响只表现在移栽后15~25 d时段内,其它时段无明显影响;对株高影响发生在移栽15d后,容重为1.33、1.27、1.12 g/cm3(D4、D5、D6)处理组增长速度明显高于其它组;对叶的影响主要表现在叶面积上,且各处理间差异显著;对叶片数、根鲜重、茎鲜重、叶鲜重、叶干重、总干物质、根冠比的影响差异不显著,对根干重的影响各处理差异显著. 相似文献