不同套种模式对小麦产量的影响

通过对不同套种模式小麦群体发育情况的调查分析,在6：2式套种（6行小麦占地1．25m,2行棉花占地0．6m）模式下,小麦理论减产率为32．43％,绝对边行优势为18．62％,套种实际减产率为14．71％,相对边行优势为26．98％;12：2：2式套种（12行小麦占地2．6m,2行棉花和2行西瓜占地1．2m）模式下,小麦理论减产率为33．33％,绝对边行优势为18．62％,套种实际减产率为14．71％,相对边行优势为38．38％。     

中秆高产冬小麦品种小区试验边行产量和内行产量研究

以4个半冬性中秆小麦品种周麦18、百农207、华育198和郑育8号为材料,对小区试验各行的内行折单产、边行折单产、全小区折单产和产量构成因素进行了研究。结果表明:1)各品种均有明显的边行优势,并且不同品种间有着较明显的差异。其中以郑育8号边行优势最强,为57.85%;百农207次之,为55.29%;周麦18居第3位,为29.69%;以华育198的边行优势最弱,为20.74%。2)4个品种的穗数、穗粒数和千粒重均表现一定的边行优势,以穗数边行优势最大、穗粒数边行优势居中、千粒重边行优势最小,依次平均边行优势为18.58%、14.21%和2.94%。不同品种穗数的边行优势由大到小依次为郑育8号百农207周麦18华育198;穗粒数的边行优势从多到少依次为百农207周麦18郑育8号华育198;千粒重的边行优势从高到低依次为百农207郑育8号周麦18华育198。3)以边行折单产,各品种产量高低依次为百农207郑育8号华育198周麦18;以内行折单产,各品种产量高低依次为华育198百农207郑育8号周麦18。以全小区折单产,各品种产量高低依次为百农207郑育8号华育198周麦18。     

小麦边际效应及其对育种选择的影响

模拟小麦杂交育种F3种植模式下的边际效应,结果表明:小麦有效穗数和千粒重的边际效应非常明显,达到1%的极显著水平;两者均为边Ⅰ行的边行优势最强,边Ⅲ行的边行优势最弱。小麦穗粒数无明显的边行优势。因此,为更准确地对小麦F3的各株行进行选择,以小麦有效穗数和千粒重作为选择目标时,可参考其边行与内行优势的变化,消除其边际效应的影响,以增加选择的可靠性。而以穗粒数作为选择目标时,选择结果会相当可靠。     

小麦品种边行优势和内行表现对小区产量的影响

小区产量是小麦育种中重要的评价指标。边行优势和内行表现对小区产量影响很大,明确不同品种间边行优势和内行表现的差异,对科学评价品种产量水平有重要意义。选取黄淮冬麦区南片株高相近的半冬性半矮秆小麦品种周麦18、华育198、郑育8号和百农207进行小区试验,分别以边行、内行和小区为收获计产方式,研究不同品种的边行优势和内行表现对小区产量的影响。结果显示,4个品种的边行产量均高于内行产量;除周麦18外,其余3个品种边行与内行间的产量差异均达显著水平。边行产量和小区产量由高到低的品种排序皆为百农207、郑育8号、华育198和周麦18;内行产量由高到低的品种排序为华育198、百农207、郑育8号和周麦18。不同小麦品种在小区试验中边行优势和内行表现会对品种产量评价产生很大影响,在小麦品种选育及推广栽培过程中应予以充分考虑。     

小麦边行优势及对育种选择的影响

对模拟小麦杂交育种F3种植模式下的边行优势进行研究与探讨,经过试验证明,在小麦杂交种植过程中,其有效穗数和每千粒质量具有非常显著的边Ⅰ行优势,甚至达到了1%的超显著水平。试验结果表明,有效穗数与每千粒质量受边行优势影响较大。所以,在进行小麦育种选择时,需要充分考虑这两种因素在边行优势中所起到的作用,提高小麦的产量。     

边行效应在套播麦种繁育田中的应用研究

本研究通过对冬小麦鲁麦15号调查分析，明确了小麦边行优势的形成具有时间积累效应：（1）小麦不同生育时期对边行产量优化形成的贡献呈现不均衡性，其大小为拔节－挑旗（31．2％）＞挑旗－开化（22．3％）＞灌浆－成熟（19．4％）＞起身－拔节（11．2％）；（2）小麦边行优势形成对产量构成的时间效应：拔节－挑旗为主要增穗期，挑旗－开花为重要增粒期，开花－成熟为增加粒重期；（3）套播麦种繁育田合理地开发利用小麦边行优势，达到了麦种和套种作物整体效益的双丰收。     

养分优化管理促进间作小麦高产群体的构建

华北平原上最近出现的、既能保障粮食安全又可提高农民收入的小麦/西瓜/玉米间作体系备受农民欢迎,但是该体系普遍存在施肥不合理,养分盈余严重的问题。因此,本研究通过单因素随机区组设计的田间试验,探讨养分优化对该体系间作小麦群体动态和产量形成的影响,为建立间作小麦高产高效技术体系提供科学依据。本试验共设置了2个施肥处理,即：农户传统施肥(Con处理)和养分优化施肥(Opt处理),在4个农户的地块进行,共8个试验小区。从小麦返青期开始,监测间作小麦在两种施肥方式下,边行和内行的分蘖数动态变化;从小麦抽穗期开始,每隔3天,监测两个处理间作小麦边行和内行的抽穗数、扬花数的动态及收获期的生物量、产量及其构成要素。研究结果表明,通过养分的优化管理,显著增加了间作小麦的有效分蘖数、抽穗数、扬花数,提高了小麦的成穗率;同时,养分优化管理也增强间作小麦的边行优势,其小麦产量同传统相比,增产11.8%,收获指数增加16.7%。因此,通过养分优化可提高间作小麦边行的收获指数,促进间作小麦高产群体的建成,边行优势的增强,有助于间作优势的提高。     

夏玉米与几种作物的间作技术

夏玉米喜光耐热,实行宽行密植栽培,可与多种作物间作种植,在玉米不减产的情况下,使单位土地面积的收入显著提高。1夏玉米与花生夏玉米宽行密植,与花生高矮间作,可充分发挥边行优势。每1.6m宽为一种植带,5月中旬在每一种植带小麦行间套种5行花生,每667m21万墩左右。5月下旬在小麦畦垄上套种玉米,行距1.6m,株距13cm,或穴距26cm双株留苗,每667m23300株左右。2夏玉米与秋土豆土豆喜冷凉,不耐高温强光,与玉米高矮间作,可利用玉米遮荫降温。玉米于5月下旬播种在小麦垄背上,行距1.8m,株距10cm,每667m23500株左右。小麦收获后灭茬整地,于8月上旬在玉…     

小麦套、复种内饲五号甜菜综合高产栽培技术

为更好地促进农业增效,农民增收,在有限的自然条件下,科学合理地利用自然资源,创造较高的经济效益,特进行了麦后复种与小麦套种饲用甜菜等项综合配套技术的试验与示范.在小麦套种甜菜的地块中复种内饲5号甜菜,试验结果表明,1.8m0.9m套种模式,临优1号小麦产量可获得299.1kg/667m2.套种内饲5号甜菜的最佳密度为株距33.3cm,块根产量达到4346.7kg/667m2,茎叶产量为2517.2kg/667m2;复种内饲5号甜菜的最佳栽培密度为株距26.7cm,块根产量为1625.5kg/667m2,茎叶产量为3819.9kg/667m2.套、复种后总产值为1799.2元/667m2,复种的增收率为43.4%,增产、增收效果非常显著.     

冬小麦边际效应研究Ⅰ.品种与小麦边际效应相关规律

该研究在高产田条件下，选择了产量潜力高但植株性状及产量构成显著不同的少穗大穗型核生2号、多穗小穗型烟农15及中间类型的泰876161品系，进行了品种-空背宽度-边际效应相关规律的研究，结果表明：（l）在间套行较窄的情况下，选择多穗小穗型品种有利于发挥边行增产作用，在间套行较宽的情况下，选择中穗或大穗型品种则更有利于发挥边行小麦的增产效果；（2）边行小麦增产，大穗型核生2号以增加穗数为主要特征，小穗型烟农15以增加穗数和穗粒数为主要特征，中间型的泰876161则是相对的穗数、粒数与粒重协调增加；（3）随空背宽度加宽，边行增产幅度提高，大穗型核生2号是增穗为主，穗粒数比重不变，粒重比重下降；小穗型烟农15是穗粒数比重提高，穗数比重持平，粒重比重下降，中间型泰87616正则是穗数、粒数比重协调增加，粒重比重下降；（4）边2行小麦的增产作用与品种和边1行的增产幅度相关，40cm空背下，少穗大穗型核生2号边2行增产幅度最高，其次是中间型泰876161，多穗小重型烟在15几乎无增产效果，空背加宽，边1行增产幅度提高，使边2行的增产幅度下降，甚至减产，100cm空背下，大穗型核生2号边2行较内行稍有增产，而小穗型烟农15和中间型泰876161则边2行出现减产，以边1行增产幅度最大的泰8761     

Analysis of power frequency electric field distortion effect on uniform electric field

The electric field sensor for the measurement of electric field in the space where the sensor probe will cause distortion in the vicinity,so it will affect the measurement of electric field accuracy. This paper uses the separation of variables method to calculate the electric field distortion caused by spherical sensor probe in uniform electric field,and detailed analysis of the 10 kV voltage,the spherical probe size,electrode material and the measuring electrode pole coupling caused the impact of electric field distortion. According to the induced voltage of sensor and the linear relationship between electric field strength,using the impact factor matrix to correct the electric field distortion. The result shows that the vicinity of the probe and the primary measuring electrodes and sub-electrodes measuring produce more serious distortion in the uniform electric field. The average distortion rate is more than 27%;however,after the impact factor matrix is used to correct the electric field distortion,the average error is about 4.47%. By analysis of the measurement of the electric field distortion with the spherical probe of sensor,it is conducive to reduce the impact of distortion on the electric field measurement and to improve the accuracy of field measurement.     

Electromagnetic field models and their influences onthe temperature field of large hydro generator

To accurately analyze the loss and heat of large hydro generator,the finite element models of 2D steady state electromagnetic field,moving electromagnetic field and field circuit coupling are established respectively.As an example,the losses of the rotor iron and damper winding of a 36 MW tubular hydro generator are calculated.Furthermore,the influences of 3 different electromagnetic field models on the thermal sources and temperatures are analyzed by 3D finite element calculation of the temperature field.The results are compared with the test data and indicate that the precision of the field circuit coupling model is better.The losses of each damp bar are different and the heat of the damp bar at the lee side is larger than that at the windward with the full load.The maximal temperature of the rotor is located at the damper winding,instead of the field winding.The research is valuable for improving the calculation precision of the rotor losses and temperature field and enhancing the reliability of the hydro generator design and operation.     

Numerical Simulation of Flow field and Temperature field in Combustion Chamber Widened Suddenly

The flowfield and temperature field are numerically Simulated by the mathematical model of the fluid flow and heat transfer in circular combustion chamber widened suddenly. The distributions and influence factors of the flow field and temperature field are studied in it. The results have the guiding significance for the design of combustion chamber. The mathematical models can serve as the quantitative analysis methods for design.     

The publication field of Euphytica

In order to give an impression if the varied publication field of Euphytica some 50 subjects are mentioned. However, there is a much wider variation since often very different cultivated plants or their characters are the subject of investigations.Euphytica can be considered as a transmitter whose programme is devoted to the international exchange of knowledge, ideas and experience in the field of plant breeding.96755 reprints of the articles published in the 7 volumes of Euphytica 1 (1952)-7 (1958) that have appeared so far, have been distributed. The reprints particularly further the contact with research workers in all parts of the world. They form elegant material of exchange between investigators interested in the same problem.Samenvatting Teneinde een indruk te geven van het gevarieerde publikatieterrein van Euphytica, zijn een vijftigtal onderwerpen met name genoemd. De variatie is echter veel groter, omdat dikwijls zeer uiteenlopende kultuurplanten of eigenschappen daarvan het onderwerp van een bepaald onderzoek zijn.Euphytica is te beschouwen als een zendstation, waarvan het programma gewijd is aan de internationale uitwisseling van kennis, inzichten en ervaringen op het gebied van de plantenveredeling.Van de 224 artikelen in de 7 thans verschenen delen van Euphytica 1 (1952)–7 (1958) zijn in totaal 96755 overdrukken geleverd. De overdrukken bevorderen in het bijzonder het contact met onderzoekers in alle delen van de wereld. Zij vormen een elegant ruilmateriaal tussen onderzoekers die voor hetzelfde probleem belangstelling bezitten.     

Predicting the field characteristics of drip irrigation

The measurements of sorptivity and conductivity for the surface and subsurface Lavalette soil, as presented in the previous paper, are used here to infer the salient features of drip irrigation experiments. Good prediction of the size of the free-water pond was obtained via Wooding's equation. Reasonable success was achieved with application of Raats' solution for the steady radial and vertical profiles of water content. However the soil's drop-off in conductivity with depth probably contributed to the observation of a greater lateral spread of water than the capillarity of the surface soil could alone sustain. Nevertheless Raats' solution is shown to be easy to parameterise. It is potentially useful for predicting solute travel times away from drippers, at least in unstratified soils.     

Mine transient electromagnetic field multiples phenomenon

In order to accurately calculate the magnetic field parameters of mine transient electromagnetic field based on the former research theory of transient electromagnetic field full-space and half-space combined with transient electromagnetic space applications in mines this article studies the relationship of transient electromagnetic field intensity and half-space transient electromagnetic field and proposes the multiple phenomenon of transient electromagnetic. Research results show that full-space transient electromagnetic field intensity and half-space transient electromagnetic field intensity has multiple phenomenon. They have 2 times relationship in the early stage and have 2.5 times relationship in the late stage. Similarly mine transient electromagnetic field intensity electric field intensity and apparent resistivity calculations also have multiple relationships. Putting forward the multiple phenomenon has important reference value in theory and practice for researching the mine transient electromagnetic field.     

龙眼园节肢动物群落结构研究

本文报道了龙眼园节肢动物群落结构特征,采用Shannon-Wiener指数、Simpson指数、Brillouin指数、物种丰富度指数、物种均匀度以及物种优势度指数分析群落多样性,采用群落相似度指数对不同时期的群落相似性进行了分析, 运用5种聚集度指标和2种回归分析方法对龙眼园2种主要害虫的空间分布型和抽样技术进行了研究。本次调查共有节肢动物13种,分属7 目12科。总的来看, 各畦间的节肢动物群落多样性指数差异不大。从水平方向来看,各畦的相似水平相差较大,说明节肢动物水平分布极不平衡; 从垂直空间水平来看,上部与中部间、中部与下部均为中解等相似水平,而上部与下部为极不相似水平。龙眼园两种主要害虫均呈现为聚集分布。     

厚皮甜瓜品种比较试验

福建春、夏雨日多,湿度大,昼夜温差小,尤其是早春阴冷、夏季湿热的气候条件,不利于厚皮甜瓜的生长,而从新疆、甘肃运来的厚皮甜瓜,往往由于长途运输造成腐烂、或未熟采收而品质欠佳,且上市期过迟。为此,我们引进了数个厚皮甜瓜品种,通过大棚栽培比较各品种在多湿气候     

Sources of variation for sustainable field pea breeding

The pea crop (Pisum sativum L.) is a convenient source of plant protein for animal feeding. The objective of this research was to evaluate field pea breeding lines for agronomic performance and seed quality focussed to their use in a sustainable production. Thirty-five field pea breeding lines and six elite cultivars were evaluated for their agronomic value in field in Spain upon 20 traits related to flower, cycle, plant architecture, productivity and seed quality. The lines showed significant differences in all the quantitative traits evaluated and three of them, namely MB-0307, MB-0308, and MB-0319 were chosen to be evaluated, together with the advanced cultivar ZP-1233, in field and in growing chamber for agronomic performance, seed quality and ability for sustainable production. The four accessions displayed high seed protein content that had significant effect of cropping density with averages of 253.6 g kg⁻¹ under low cropping density of 60 plants m⁻² and 259.1 g kg⁻¹ under high cropping density of 90 plants m⁻², therefore, the low cropping density should be regarded as the most convenient. Average yield of the lines MB-0307, MB-0308 and MB-0319 and the cultivar ZP-1233 was fair (197.5 g m⁻²), probably due to the absence of fertilizers and irrigation, aiming for the sustainability of the crop. Intercropping with rye and herbicide application resulted in no differences on the seed yield; therefore, the ability of the breeding lines to grow without herbicide seems to be demonstrated, while the germination of the seeds at low temperature was very good. These results indicate that field pea could be a new protein crop in the North of Spain to satisfy the demand of plant protein for animal feed, based upon adapted breeding lines that combine the ability for growing under sustainable conditions with other desirable agronomic traits maintaining an adequate productivity.