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1.
Field experiments were carried out on grey‐brown podzolic soil in the four consecutive growing seasons (1998–2001) at Krzeslice Farm, central‐western Poland. The effect of seven N fertilization treatments (in kg N ha?1): 80NF + 80CAN; 80NF + 50CAN + 30CN; 80CAN + 80CAN; 80CAN + 80CAN + 30CN; 80AN + 80AN; 80AN + 50AN + 30CN, where, NF – nitrofos NPK, CAN – calcium‐ammonium nitrate, AN – ammonium nitrate, CN – calcium nitrate and control (without N) on N uptake dynamics and N efficiency was studied. Mineral fertilizers were applied at the start of spring regrowth, beginning of stem elongation and at the flower‐bud‐visibility stage. The study revealed two distinct strategies of oilseed rape plants’ adaptation to timing and N fertilizer application sequences. Both strategies based on nitrogen uptake rate (NUR), were analysed at different plant growth stages. Ammonium nitrate (AN) applied in the two‐split system gave the highest NUR (387 mg m?2 day?1) during stem elongation (for comparison, a value of 166 mg m?2 day?1 was obtained in the control). In the case of calcium‐ammonium nitrate (CAN), a moderate level of NUR was obtained (304 mg m?2 day?1) but N uptake lasted 12 days longer compared with the AN treatment. Hence, N accumulation in leaves at the end of flowering explained about 81 % of yield variability. The second adaptation strategy was attributed to the three‐split N treatment. Plants fertilized with AN and CAN fertilizers showed an inconsistent pattern of NUR with time. Nitrogen accumulation in stems at the beginning of maturity, explained 69 % of yield variability. Nitrogen‐use efficiency did not show any response to N treatments.  相似文献   

2.
In this study a stochastic approach, based on several simplifying assumptions, is developed that allows an estimation of the effects of nonregular spatial patterns of the distribution of individual plants on yield per area. In this approach, two random variables were attached to each individual plant: single plant yield and individual space per plant. The latter can be estimated, for example, by the area of Thiessen polygons. Yield per area is calculated theoretically by the expectation (=mean) of the ratio between individual yield and area. Based on the logarithmic relationship between single plant yield and individual space per plant, yield per area can be broken down into three additive terms: the first term depends only on the mean of individual plant areas, while the second depends on their mean and variance simultaneously. This second term is the product of the variance and a factor which depends only on the mean. The third term is a function of the mean and of higher order (≥ 3) central moments of a fractional linear transformation of individual plant area. Finally, these theoretical concepts were applied to 17 experimental data sets of three cultivars of winter oilseed rape (Brassica napus L.) with measurements for single plant yields and individual areas for the Thiessen polygon tesselations. Since yield per area is theoretically defined by the expectation of the ratio between individual yield and area, it is estimated by the arithmetic mean of the individual yield/area‐ratios. The agreement between this estimate and the sum of the estimated terms from the aforementioned additive decomposition of yield per area is particularly good. For the 17 data sets, percentages for these additive terms of approximately 71.4 % up to 98.4 % (mean: 89.0 %) for the first term, 1.6 % up to 20.0 % (mean: 9.8 %) for the second term and 0 % up to 8.7 % (mean: 1.2 %) for the third term are obtained. As a consequence it may be concluded, that yield per area can be explained mainly by dependencies on the means of individual plant areas while the variance of individual plant spaces is of only minor importance. The effect of the third term is insignificant. These results clearly indicate an answer to the main issue raised in the paper, namely the importance of seeding density as opposed to seeding accuracy/uniformity: nonuniformity is of limited influence and seeding density is the main correlate of yield/area. Seed placement accuracy of seeding technology therefore plays an only minor role.  相似文献   

3.
To determine the effect of different preceding crops and crop rotations on the grain yield of oil-seed rape, a long-term rotation experiment was conducted at the Hohenschulen experimental station in Kiel, NW Germany. Additional factors included the nitrogen fertilization and the fungicide application. The results reported herein are based upon the harvest years 1988 to 1993. Averaged over the different rotations and husbandry treatments, the grain yields in the 6 experimental years varied between 2.71 t ha?1 and 3.99 t ha?1. In contrast, the effect of the different husbandry treatments was smaller and non significant. Averaged over 6 years, only the fungicide application caused small yield increase of 0.2 t ha?1. The highest grain yields of 3.77 t ha?1 or 3.65 t ha?1 occurred when oil-seed rape was directly following peas. Low yields between 3.15 tha?1 and 3.33 tha?1 were obtained when oil-seed rape was grown after oilseed rape. The lowest grain yield of 3.13 t ha?1 was produced with oil-seed rape grown in monoculture only. In rotations with oil-seed rape following a preceding cereal crop (wheat or barley), the grain yields averaged between 3.22 tha?1 in a two course rotation and up to 3.44 tha?1 in a four course rotation. In general, the yields of oil-seed rape increase with the length of the rotation and the length of the break between two oilseed rape crops. The yield component number of seeds per m2 was affected by the previous cropping accordingly, whereas the thousand seed weight did not respond to the cropping history. Based upon disease assessments in the first years of this experiment, we argue that an increase in the incidence of fungal diseases has considerably contributed to the yield decrease of oil-seed rape in short rotations.  相似文献   

4.
The effects of stand establishment and nitrogen fertilizer on yield and yield stability of winter oil-seed rape ( Brassica napus L.) were investigated in two field experiments in north eastern Germany (Mecklenburg-Vorpommern). During six years of testing from 1984/85 to 1989/90 three sowing dates (10 Aug, 20 Aug, 5 Sept) as combined with three plant densities (60, 100, 140 plants/m2 in autumn) were compared. Although seed yield did not respond to the main effects of these treatments, the two-way classification resulted in significant differences from the average yield. August sowing combined with lower plant densities caused comparably high yields, while delayed sowing was somewhat effective only with higher plant density. Highest yield stability was achieved at early sowing when combined with lower plant densities. From 1986/87 to 1988/89 nitrogen top-dressings were applied during early March, at start of stem extension and shortly before start of flowering at five locations. 200 kg N/ha in one dose resulted in lowest yield performance and enhanced instability. Contrastingly, the 240 kg N/ha treatment advanced yield stability regardless of split regimes. Nevertheless, split application to 100 kg N/ha + 50 kg N/ha + 50 kg N/ha also guaranteed that high yield performance and optimum yield stability were reached simultaneously and, that the total nitrogen input could be limited to 200 kg N/ha.  相似文献   

5.
Based on well-known statistical approximations for the mean, variance, and for the third moment about zero of the ratio of two random variables, a general expression has been derived for the skewness of the distribution of harvest indices. The skewness of the distribution of harvest indices depends on three parameters: coefficients of variation for the two component traits and their correlation. Conclusions for the sign of this skewness are discussed. Finally, the theoretical results and conclusions have been checked and applied to an experimental data set of winter oilseed rape. The agreement between expected and observed skewness is extraordinary good.  相似文献   

6.
Growth and yield responses to plant density (6.75 × 104, 9.75 × 104 and 12.75 × 104 plants ha–1) and stage of transplanting (30, 35 and 40 days after sowing) of winter oilseed rape cultivar HO 605 were investigated in two field trials in the 1996/97 and 1997/98 growing seasons at Zhejiang University Farm, Huajiachi Campus, China. Results revealed a progressive decrease in leaf area per plant in response to increasing plant density and delayed transplanting, though leaf area m–2 and leaf area index were higher in high-density plants. Number of effective branches and pod per branch decreased with increasing plant density and delayed transplanting. There were no significant differences in the mean seed weight among treatments. Although the average number of seeds per pod was significantly lower for high-density plants and delayed transplanting, the economically highest seed yields were realized in relatively high-density plants. Seed oil content was negatively affected by increasing plant density, but no significant differences were observed with delayed transplanting. The highest seed yields of 1730.7 and 1748.1 kg ha–1 with no significant differences were observed for plant densities of 9.75 × 104 and 12.75 × 104 plants ha–1, respectively, transplanted at 35 and 30 days after sowing.  相似文献   

7.
油菜套播是利用双季稻区冬闲田的有效手段,为探究缓释型配方肥(N-P2O5-K2O:25-7-8,及5%的中微量元素)在晚稻套播油菜上的施用效果,设置一次性基施缓释型配方肥与分次施常规肥效果对比试验和配方肥施用量试验,调查油菜产量形成、肥料利用率及经济效益。结果表明,在减少肥料养分投入且一次性基施的情况下,缓释型配方肥仍能达到甚至优于常规肥分次施用的效果。菜籽产量与缓释型配方肥用量呈线性加平台关系,适宜施肥量可保证较大的收获密度并产生较多的每株角果数和每角粒数,同时维持较高的肥料利用率,从而提高籽粒产量和经济效益。根据本试验结果推算出晚稻套播油菜的目标产量为1 500~1 800kg/hm2时,缓释型配方肥的适宜用量为645~715kg/hm2。  相似文献   

8.
长江流域直播冬油菜氮磷钾硼肥施用效果   总被引:16,自引:1,他引:16  
冬油菜直播种植的推广应用对提高我国油菜籽总产量和保障食用油安全有重要意义。2009-2010年度在长江流域6个冬油菜主产省布置36个大田试验,研究当前生产条件下我国直播冬油菜的氮磷钾硼肥施用效果和肥料利用率,比较农民习惯施肥与推荐施肥的差异,并与移栽油菜施肥效果进行对比,以探讨直播冬油菜的施肥管理措施。结果显示,在推荐施肥量和施肥方法条件下,氮磷钾硼肥配合施用(NPKB)处理直播冬油菜的油菜籽产量和产值平均分别为2001 kghm–2和8205元hm–2,显著高于农民习惯施肥(FFP)处理,施用效果为N > P > B > K。NPKB配合施用显著促进直播冬油菜的养分吸收,N、P、K累积量分别为104.2、20.4和160.2 kg hm2。NPKB配施条件下,直播冬油菜的氮、磷、钾肥表观利用率平均分别为35.8%、22.3%和45.9%,明显高于农民习惯施肥的20.8%、7.2%和28.0%。说明合理施肥对直播冬油菜生产有重要作用,现阶段应积极推行氮磷钾硼肥配施技术,并根据生长发育特点和养分吸收规律调整肥料的施用时期和比例。  相似文献   

9.
The spectroscopic changes in reflectance and fluorescence caused by phosphorus (P) starvation in Brassica napus L. young plants were evaluated. P deficiency produced an important decrease in reflectance values between 500 and 650 nm for both intact leaves and cotyledons. Furthermore, cotyledons under P deficiency showed a Chl-F ratio in the red/far-red region (Fred/Ffar-red) lower than that of non-stressed plants (1.91 and 2.89 respectively). As minimal differences in Fred/Ffar-red were detected in leaves, P deficiencies may be better perceived by measuring changes in Chl-F emission in cotyledons than in leaves. Stressed cotyledons also showed different emission spectra in the blue green (maxima at 470 and 560 nm) from those of non-stressed cotyledons. The results are explained in terms of higher anthocyanin and chlorophyll contents and of damage to photosystem II. We evaluate that measuring variations in fluorescence and reflectance data may be useful to detect early damages induced by P stress.  相似文献   

10.
氮钾配施对油菜产量及氮素利用的影响   总被引:2,自引:0,他引:2  
实际生产中氮钾肥投入不平衡严重限制了氮肥肥效及作物的产量潜力。为了探明不同施氮量下钾肥施用对油菜产量及氮素利用的影响,于2016—2017年及2017—2018年在湖北省武穴市开展连续2年的田间试验,采用氮钾两因素完全试验设计,设氮0、90、180、270 kg N hm-2和钾0、60、120、180 kg K2O hm-2各4个水平。在油菜成熟期取样测定产量、地上部氮钾积累量以及氮肥利用率。结果表明,在钾供应不足时(K0和K60),冬油菜施用氮肥的平均增产率为113.7%,而在钾供应充足的条件下(K120和K180),施用氮肥的平均增产率高达172.9%;与K0处理相比, K120处理冬油菜氮肥回收利用率平均提高了16.6%,继续增施钾肥对不同施氮量下冬油菜氮肥回收利用率的进一步提高无显著影响;达到区域平均产量时,钾供应充足较低钾(K60)投入平均降低33.9%的氮肥用量。综上所述,氮钾配施显著提高了冬油菜产量和氮肥利用率,在冬油菜实际生产中除了重视氮肥施用外,应增加钾肥投入,通过优化氮钾肥配施比例可进一步提高油菜产量,实现冬油菜高产和养分高效。  相似文献   

11.
为探讨气候变化对我国油菜生产带来的可能影响,选取江苏省地区52个气象站1961—2012年日气温资料及冬油菜产量逐年数据,采用M-K趋势检验探求冬春季节8种低温指数的变化趋势,并依托一阶差分法探讨低温指数与产量的数量关系。结果表明:(1)1961-2012年间省内大部分地区冬春季节低温事件的总天数、连续低温事件的场次、强度及持续性呈现出显著的减弱趋势;(2)不同类型低温指数中,FI1(越冬期日最低气温<-5℃的总天数)与CI4(蕾薹期连续日最低气温<0℃天气的最长持续时间)对冬油菜产量的负效应最为显著;(3)各站点产量对FI1及CI4敏感性分析表明江苏省北部地区冬油菜种植对低温灾害事件更为敏感;(4)1961-2012年间江苏大部分地区FI1及CI4的减少趋势给研究区冬油菜产量带来了一定幅度的增产。  相似文献   

12.
为了给旱地农业水肥管理以及科学施肥提供参考依据,通过田间试验研究了油用亚麻氮磷配施后土壤水分分布及其对产量和水分利用效率的影响。结果表明,施肥对土壤含水量有较大的影响,在中氮和高氮水平下,油用亚麻各生育时期100 cm以下各土层含水量均表现为施磷处理高于不施磷处理;在子实期高氮施磷处理的土壤贮水量显著高于其他不施磷肥处理,分别高4.38%、3.37%和3.66%;氮、磷单一施用时,土体供水的贡献率均偏向于某一土层,而氮磷配施时,各个土层土体供水贡献率都表现适中;高氮施磷处理的籽粒产量和水分利用效率均显著高于其他处理,分别达1062.50 kg/hm2 和2.60 kg/(mm· hm2),产量较其他处理增加8.12%~16.76%;WUE分别较其他处理提高7.31%~15.77%。  相似文献   

13.
Genetic analyses were carried out with B. napus lines that differed in total content of individual glucosinolates (GSLs), as well as in their profile. Inheritance of total GSL content was studied with a complete F1 diallel mating of eight doubled haploid (DH) lines (5–120/μmol GSL/g dry seed) as well as with the segregating populations of two crosses between DH lines. Most of the genetic variability was caused by gca effects; heterosis was not important; heritability of GSL content was high (h2b, = 0.95, h2n= 0.87). For GSL contents below 20/μmol/g seed, heritability values reached h2b, = 0.69 and h2n, = 0.66. Low total GSL content was found to be controlled by 4–5 recessive genes with additive gene action. Alkenyl GSL profiles studied in F2 from resynthesized rapeseed lines were determined by four loci, two that are responsible for the elongation of the butenyl to pentenyl GSLs and two that are responsible for hydroxylation of alkenyl GSLs. Initial genetic studies of indolyl GSL contents from 0.1–4.5/μmol/g show that two or three genes may be involved. The frequency distribution of F2 phenotypes was virtually continuous due to both segregational and environmental variation. Genotypes with low alkenyl and low indolyl GSL contents were selected after crossing parents with low alkenyl/high indolyl and high alkenyl/low indolyl GSL content. The alkenyl GSL profiles are discussed with regard to the parental diploid species B. oleracea and B. campestris.  相似文献   

14.
Cultivars of European winter oilseed rape cultivated in the second half of the 1970s and in the mid-1990s were screened for their winter hardiness, frost resistance and vernalization requirement. A strong correlation between winter hardiness and frost resistance in both groups of rape has been noticed. Among oilseed rapes cultivated in the late 1970s, low erucic acid and particularly double zero cultivars were less winter hard than high erucic acid cultivars. Double zero cultivars were characterized by lower frost resistance and lower vernalization requirement. A significant correlation between vernalization requirement and both frost resistance and field survival has also been shown. Frost resistance of the 1990s (double zero) cultivars was higher than that of double low cultivars from the late 1970s. Their vernalization requirement was still small and did not correlate with either frost resistance or winter hardiness. It was concluded that reduction in the content of glucosinolates in the 1970s involved decrease in winter hardiness and vernalization requirement of cultivars. During the following 20 years winter hardiness of double low cultivars has been improved, but vernalization requirements have not changed. As a result no correlation between winter hardiness and vernalization requirement in contemporary canola cultivars has been observed.  相似文献   

15.
为了明确稳定氮肥在油菜生产上科学施用问题,2014-2015年于安徽省通过田间小区试验,研究了稳定氮肥用量及施用方式对油菜产量、氮素累积量、氮肥利用效率、经济效益及土壤养分含量的影响。结果表明,与不施氮肥相比,100%稳定氮肥一次施用、100%稳定氮肥分次施用、85%稳定氮肥一次施用和70%稳定氮肥一次施用分别增产225.6%、232.5%、206.8%和181.2%,植株地上部氮素总累积量分别增加309.2%、327.6%、254.0%和202.1%,经济效益分别增加287.9%、273.9%、266.1%和234.0%。与农民习惯施肥相比,100%稳定氮肥一次施用和分次施用分别增产8.2%和10.5%,植株地上部氮素总累积量分别增加15.2%和20.3%,经济效益分别增加16.8%和12.6%。等氮施用稳定氮肥较农民习惯施肥显著促进油菜对氮素的吸收累积。氮肥表观利用率施用稳定氮肥显著高于农民习惯施氮,等氮显著高于减氮处理,以100%稳定氮肥分次施用最高。农学效率和偏生产力施用稳定氮肥高于农民习惯施肥。稳定氮肥施氮量在180 kg/hm2且基肥与薹肥6:4分次施用时,能较好地协调水稻高产与稳定氮肥合理利用的统一。  相似文献   

16.
氮磷钾配比对不同肥力土壤油菜产量与经济性状的影响   总被引:2,自引:2,他引:2  
为合理利用肥料,发挥品种基因型优势,促进油菜高产稳产,本研究以‘丰油10号’为试验材料,在大田条件下考查了氮磷钾配比对2种不同肥力土壤油菜产量与经济性状的影响,采用统计分析法比较分析了不同肥力土壤对施肥响应的特点与差异。结果表明:与不施肥处理相比,不同氮磷钾配比均可显著提高油菜的产量、株高、有效分枝高和主花序有效角果数,氮磷钾肥配比为15:9:6时,油菜产量及主花序有效角果数均达到最高;相同施肥处理条件下,油菜产量、千粒重、单株有效角果数、一次有效分枝数、株高、有效分枝高、主序有效段长及有效角果数均表现出随土壤肥力升高而增加的趋势,但贫瘠土壤中的油菜产量始终低于中等肥力土壤的产量水平。结果说明,土壤肥力对油菜产量与经济性状具有重要影响,平衡配施氮磷钾肥,培肥土壤肥力,保证油菜全生育期正常生长发育的养分供给,是实现油菜稳产高产的关键。  相似文献   

17.
硼对甘蓝型双低春油菜产量和品质的影响   总被引:3,自引:0,他引:3  
旨在阐明硼对甘蓝型双低春油菜产量和品质形成的影响机理,明确甘蓝型双低春油菜产量和品质形成与施硼量的关系。试验以甘蓝型双低春油菜"青油14"为供试材料,采用单因素五水平随机区组设计,研究了不同施硼量对甘蓝型双低春油菜产量和品质形成的影响。结果表明:甘蓝型双低春油菜单株角果数与施硼量之间呈显著线性关系,而每角果粒数则与施硼量呈二次曲线关系,适量施硼可以协调每株角果数与每角果粒数的关系,有利于提高产量。籽粒产量与每角果粒数呈极显著正相关性(r=0.982 8**),与单株一次有效分枝数和千粒重也呈一定的正相关性,而与单株角果数则呈一定的负相关性。适量施用硼肥,可明显提高甘蓝型双低春油菜的籽粒产量和产油量,增加籽粒粗脂肪和粗蛋白质含量,而降低硫苷含量,进而改善品质。籽粒产量、产油量与施硼量之间均呈二次曲线关系,施硼量分别为17.84 kg/hm2和19.42 kg/hm2时,籽粒产量和产油量分别达到理论最大值3 154.18 kg/hm2和1 344.61kg/hm2,施硼过量,籽粒产量、产油量均下降。粗脂肪含量与施硼量之间呈单峰曲线关系,粗脂肪含量达到最大值(45.3%)时的施硼量为24.62 kg/hm2。硫苷含量与施硼量则呈开口向上的二次曲线关系,施硼量为19.42 kg/hm2时,硫苷含量为10.29 mg/g(≤30 mg/g)。试验综合考虑甘蓝型双低春油菜的籽粒产量、产油量及籽粒综合品质,提出适宜的施硼量(含硼11%)以19.42 kg/hm2为宜。  相似文献   

18.
Germinating seeds and young plants of winter rape var. Górczañski were vernalized for 56–63 days under conditions of 9-hour day, at the temperature 2 and 5 °C and in continuous darkness at the temperature 2 °C. After vernalization the plants grew under conditions enabling to complete vernalization: in a glass-house at the temperature day/night 15/10 °C and in semi natural conditions of open vegetation hall in the period from June till August. After sub-optimal vernalization further growth of the plants at lowered temperature increased its effectiveness (completion of vernalization). Depending on the degree of the vernalization of the plants the completion of their vernalization was both obligatory, i.e. conditioning the acquisition of the ability of generative development, and facultative i.e. accelerating this development. It has been demonstrated that the population of plants of the examined variety is strongly differentiated not only with respect of vernalization requirements in the particular plants, but also what regards the effectiveness of vernalization completion. New observations have been made indicating that the mechanisms controlling the successive phases of generative development, i.e. phase of forming flower buds and the flowering phase are not identical which may be interpreted as indicating that the "flowering factor" is polymorphous.  相似文献   

19.
A factorial experiment with 3 nitrogen (N) levels and 4 application rates of the triazole type plant growth regulator (PGR), BAS 111 W = l-phenoxy-3-(1H-1,2,4-triazol-1-yl)-4-hydroxy-5,5-dimethylhexane, was conducted in hydroponics to study the influence on N uptake and morphological changes of oilseed rape. The following results were obtained:
–Increased N level of the nutrient solution increased plant height and root and shoot weight. Enhanced N uptake caused a higher N concentration of root and shoot.
–Increasing PGR application rates reduced plant height and shoot biomass production; this reaction was stronger at higher doses of N.
–Root weight, root length, root diameter and root surface area were increased by N application. None of these parameters was significantly altered by the PGR. This resulted in increased root-shoot-ratios at higher PGR rates.
–As a consequence of reduced shoot production PGR application resulted in increased concentrations of N. The root reacted similarly but to a lesser degree.  相似文献   

20.
不同种植密度下油菜产量与茎叶性状对施肥水平的反应   总被引:3,自引:3,他引:3  
为探明种植密度和施肥水平对油菜生长与产量的影响及其机理,此文采用大田小区试验,研究了高、中、低(分别为7.5、22.5、37.5万株/hm2)3种密度条件下冬油菜籽粒产量和茎叶性状对4种施肥水平的反应。结果表明,在供试3种密度条件下,籽粒产量、单株角果数、每角果粒数、千粒重、越冬期和盛花期的根颈直径、越冬期单株绿叶数、盛花期单株主茎绿叶数、越冬期最大叶长和宽、盛花期第一片无柄叶长和宽均随着施肥量的增加而增加,但增加幅度因密度不同而异,籽粒产量和越冬期根颈直径在中密度条件下、其余各项指标在低密度条件下增加幅度最大,而在高密度条件下所测各项指标的增加幅度均最小。因此,所有处理中,籽粒产量和越冬期根颈直径以中密度、高施肥量处理(N、P2O5、K2O、B分别为240、120、210、1.2 kg/hm2)的最高,其他各项指标均以低密度、高施肥量处理的最高。不同种植密度下油菜产量与茎叶性状对施肥水平的反应各异,其中以越冬期根颈直径受个体间竞争的影响相对较小,在不同密度条件下随施肥量的变化趋势于籽粒产量一致,所以能更好地反应油菜生长和产量情况。  相似文献   

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