豆科牧草与禾本科牧草抗盐碱种植模式研究

研究不同牧草品种在盐碱地上的适应性及种植模式对盐碱地作物的影响。结果表明:高丹草具有较强的耐盐碱性,在重度盐碱地上仍能获得较高产量,其鲜草产量和干草产量分别是单作苜蓿的3.70和4.90倍,是单作燕麦的4.27和7.80倍。粗蛋白产量是苜蓿与燕麦混作处理的4.5倍。不同种植模式中,燕麦和苜蓿混作时的脱盐效果最佳,水溶性盐总量较对照低6.13g/kg,且混作时作物鲜干比最大,适口性好,而且混作提高了鲜干草及蛋白质产量。单作模式中,燕麦脱盐效果最好,在盐碱地上有较强的适应性。     

玉米大豆混作系统氮素转移特性的研究

在不同氮水平土壤上用１５Ｎ同位素稀释法对玉米大豆混作系统氮素转移特性进行了研究。结果表明，低氮和高氮土壤上均发生了固氮产物的转移。低氮土壤混作玉米从大豆固氮产物中获得１４．９４％～２６．９６％的氮，在高氮土壤上仅获得２．５６％～２１．１３％的氮；混作大豆固氮率的提高率，低氮土壤为—１０．３６％～—２１．１４％，高氮土壤为２９．１０％～３２．６９％；混作玉米和混作大豆的植株含氮量，在低氮土壤中均比单作降低，而在高氮土壤上则有不同程度的提高。玉米大豆混作系统在低氮土壤上主要消耗土壤速效氮，在高氮土壤上主要消耗土壤全氮。     

麦类作物蓝粒性状遗传与调控机制研究进展

麦类作物是我国主要的粮食作物,大部分麦类作物籽粒的种皮、果皮或胚乳因花青素的积累表现出蓝、紫、黄或黑等不同颜色。蓝粒麦类作物含有许多优异的品质性状。本文从麦类作物籽粒颜色的分类、蓝色的籽粒品质、蓝粒性状的形成及遗传方式、基因定位和调控机制方面进行综述,并提出了展望,为进一步认识和利用蓝粒麦类作物提供参考,也为麦类作物蓝粒性状基因的精细定位和形成机制研究提供依据。     

小麦种内混作研究进展

混作是千百年来我国农业遗产的重要组成部分,是精耕细作、集约种植的一种传统技术.小麦又是我国三大粮食作物之一.综述了不同小麦品种混合种植产量增加的机理,概述了现有的小麦混作的模式及其不同品种的配比原则,以及小麦混作在环境保护中的积极作用,指出了未来小麦种内混作的研究方向,提出了在小麦种内混作实践过程中应该注意的问题,以期为进一步的提高混作小麦复合群体的生产潜力提供参考.     

玉米不同品种混作增产机理研究

以基因型不同、表现型有一定差异的玉米单交种组成两个混作群体.对混作与单作群体的产量、群体结构、生理指标、田间小气候等因素进行比较研究.结果表明:不同品种的合理混作增产效果显著.混作增产的机理主要在于群体结构的改善和品种间的差异互补.混作群体的立体式结构即凹凸式冠层使群体受光面积增加,冠层内光照增强、通气性改善、CO2浓度提高,在光合速率、叶绿素含量等方面也都有不同程度的改善,为群体增产奠定了基础.     

麦类作物水肥耦合研究进展

简述了国内外近些年麦类作物水肥耦合研究的结果,总结了水肥耦合的含义、水肥耦合效应对麦类作物生长发育、产量,水肥利用率,光合及生理特性、土壤养分变化及作物品质的影响。提出了今后的研究方向。     

青稞：β-葡聚糖含量最高的麦类作物

西藏自治区农牧科学院农业研究所副所长、青稞作物研究专家强小林在对西藏75个青稞品种研究后发现，“藏青25”青稞新品种的β-葡聚糖含量商达8．62％，是目前世界上含β-葡聚糖最高的麦类作物。     

小麦不同品种间作和混作对麦蚜发生量的影响

通过小麦不同品种的间作、混作,以期用其本身物种的多样性控制麦蚜发生数量。实验通过将5个小麦品种在田间间作和混作组合,以单作小麦品种为对照,在小麦关键期和麦蚜盛发期调查麦蚜发生数量,用蚜量比值法比较不同小麦品种间的抗虫性,用麦蚜发生量比较不同组合间的差异并对比其防治效应。结果表明：各单作品种的感虫程度为高感：石7816>95-108>兰天13,感虫：兰天6>兰天1;在扬花期和灌浆期所有间、混作组合麦蚜发生量至少显著低于其中一种单作品种(P<0.05);在扬花期和灌浆期,除兰天1/石7816、兰天13/95-108、兰天6/95-108和兰天1/95-108这4个组合出现了防治效应负增长外,所有间、混作组合均对麦蚜有防治效果,间作的平均防治效应为12.94%,变化范围为-24.67%~44.33%,混作的平均防治效应为28.92%,变化范围为1.67%~61.33%,防治效应最好的组合均是兰天1/兰天6/兰天13/95-108/石7816,防治效应分别为44.33%和61.33%。研究结果表明不同小麦品种间作、混作大部分对麦蚜的发生量有较好的防治效果。     

油菜与紫云英混作系统的密度效应研究

油菜和紫云英混作,在相同的土壤肥力环境条件下进行试验,研究油菜和紫云英混种的7个不同用种量(即混作密度)对油菜植株干物质积累、分枝特性以及产量结构的影响。结果表明:以油菜2·1kg/hm²,紫云英6·75kg/hm²混作散播为较适宜的混作种植密度。在这种组合密度下既可以获得较高的油菜产量和紫云英产量,还能为后茬作物增产提供较高的土壤肥力,为实现持续增产打下良好的基础。     

不同基因型玉米混作研究初报

用3个不同株高的玉米单交种组配成两个混作群体,对群体产量、产量构成因素、形态指标等进行了相关分析。结果表明:在不增加任何生产成本的情况下,A·B混作增产3%左右,B·C混作增产7%左右;混作后茎折率较单作明显降低。分析表明,混作增产的原因在于群体结构的改善和品种间的差异互补,而当代杂种优势的作用对增产效果影响不大。     

利用品种混合控制小麦病害之研究进展

作物多样性在病害防治上的应用包括多系混合、品种混合和物种混合,其中品种混合策略备受重视。对于小麦,品种混合与它的组分净种时的表现相比至少有两方面的优势,即增加籽粒产量的稳定性和减少病害的危害．特别是对减轻锈病和白粉病的危害更为明显。但是,由于病害防治而获得的产量收益比较小．一般平均只有4％-5％。对于小种专化的病原物,小麦混合群体中复杂小种(能侵染两个或两个以上混合组分)的相对频率高于简单小种的情况并不少见,因此有必要实行小组分数目品种混合系统的多样化、增加组分之间的抗性差异或增加混合组分数目。影响品种混合防病效应的因素是今后需要大力研究的问题。     

Dry Peas (Pisum sativum L.) Grown in Mixtures with Faba Beans (Vicia faba L.)—A Rewarding Cultivation Alternative

Two semi-leafless pea cultivars and two highly lodging-resistant faba bean cultivars were grown in a series of replacement trials conducted on a highly fertile loam soil near Gottingen from 1992 to 1995. Cultivation as well as harvesting of mixed crops of both species proved possible. In spite of the delayed harvest of the mixed crop stands determined by the later pod ripening of the faba beans (varying between seasons from -f 5 to +21 days), noticeable seed losses due to pod shattering were not observed for the overripe peas. Standing ability of the peas was considerably improved by mixed cropping. Lodging began later and was less severe at harvest. Within mixtures with 50 % or more faba bean proportions at sowing (relative to the seeding rate of the pure stands) the peas, n i most cases, remained nearly upright until harvest and instead of the usual 'Plattlager', i.e., prostrate but upright top, frequently a more highly inserted 'Hohllager', i.e., upright but collapsed at higher nodes, was observed. In contrast to these remarkably synergistic effects for standing ability, such effects proved to be only small and nonsignificant for grain yield (−1.5–2.9%). Yield stability of the mixed crops was higher than that of the pure stands of both species. Estimates of the stability parameters, ecovalence, deviation from regression and environmental variance were at least halved. Yield proportions of peas and faba beans in the harvested seed of the mixtures did not correspond with the seed proportions at sowing. They differed considerably between seasons and cultivar combination. Higher yield proportions of faba beans were observed under wet and cold weather conditions and for the cultivar combination Victor/Disco, whereas higher yield proportions of peas were found under dry and warm weather conditions and for the cultivar combination Mythos/Baroness .     

Yield and Persistence from Mixtures of a Winter Hardy and a Verticillium Wilt Resistant Lucerne Cultivar

In British Columbia, Lucerne stand persistence is reduced by inadequate disease resistance, winter hardiness, or both. We evaluated the possibility that persistence could be improved by sowing mixtures of winter hardy and verticillium wilt (VW) resistant cultivars. Our hypothesis was that dry matter yield of mixtures of two Lucerne cultivars could be calculated simply from the proportion of each cultivar in the mixture and their yield in pure stand. A winter hardy cultivar, Beaver, was grown in mixtures with each of three VW (caused by Verticillium albo-atrum Reinke & Berthier) resistant cultivars (WL316, Sparta, or Barrier) in proportions of 0, 0.25, 0.5, 0.75, and 1.0. The yield of a mixture of two cultivars could be calculated from the proportion of each cultivar in the seed mixture and their yields in monoculture. In the absence of a winter where severe injury to Lucerne stands occurred, the VW-resistant cultivar Barrier yielded about 2 t ha⁻¹ year⁻¹ more than the more winter hardy Beaver.     

小麦族的基因组显性及其育种学意义

小麦族包含大量由不同基因组组成的异源多倍体物种。同一个异源多倍体物种的不同基因组可能对表型性状产生非对称性贡献,例如小麦属多倍体物种的形态分类特性,更像其A基因组供体物种,这种现象称为A基因组显性。由于基因组显性,小麦族形成了以A、D、U、St为轴心(显性)基因组的异源多倍体物种簇。异源多倍体物种的基因组显性可能与其进化适应优势的形成有关。在育种方面,基因组显性影响多倍体新作物开发及小麦-外源染色体易位设计。     

A mathematical model for the evaluation of cooperation and competition effects in intercrops

Experimental results showing cooperation–competition interactions in dual-component crops for mixtures created from Pisum sativum L. (pea), Vicia sativa L. (spring vetch) and Linum usitatisimum L. (linseed) are studied by means of a mathematical model describing the plant interactions. The model introduces parameters enabling to distinguish competition and cooperation between the species in the crop. The model parameters are established on the basis of the entire vegetation period of plants, so they provide exhaustive characteristics of the plant interactions in the mixtures. The model factors allow the estimation of the mixtures with respect to the final biomass yield as well. The experimental data verify possible economic benefits from the proposed plant mixtures and allow to critically check the beliefs that legumes improve the field productivity. Additionally, for comparison with the biomass yield, the seed yield is analyzed in the respective crops. Especially, it is indicated that the increased biomass yield for linseed in the mixture with a leguminous plant is accompanied with a decrease of the seed yield for this species. As concerns pea in the mixture with linseed, a decrease in the pea biomass was registered when compared to the sole crop but at the same time an increase in the seed yield was achieved in the mixture. No influence on the biomass of the spring vetch was noticed when it was cultivated with linseed but its seed yield appeared to be diminished with respect to the sole crop.     

利用品种混合控制小麦病害的研究进展

作物多样性在病害防治上的应用包括多系混合、品种混合和物种混合,其中品种混合策略备受重视。对于小麦,品种混合与它的组分净种时的表现相比至少有两方面的优势,即增加籽粒产量的稳定性和减少病害的危害,特别是对减轻锈病和白粉病的危害更为明显。但是,由于病害防治而获得的产量收益比较小,一般平均只有4%~5%。对于小种专化的病原物,小麦混合群体中复杂小种（能侵染两个或两个以上混合组分）的相对频率高于简单小种的情况并不少见,因此有必要实行小组分数目品种混合系统的多样化、增加组分之间的抗性差异或增加混合组分数目。影响品种混合     

Effekte der Sorten- (Weizen)und der Arten- (Weizen, Roggen) Mischung auf die Ertragsleistung krankheitsfreier Bestände

Effects of cultivar (wheat) and species (wheat, rye) mixtures on grain yield of desease-free stands
Cultivar mixtures (winter wheat) and species mixtures (winter wheat/winter rye) grown free from pests and diseases in different environments are compared to pure stands and analyzed with respect to inter-component relationships relevant for yield. All mixtures consisted from two components which were planted 1:1. Mixing effects (i.e. deviations from arithmetic mean of respective components grown in pure stands) on grain yield/ha and yield structure were dependent on components and growing conditions, particularly nitrogen availability. Under conditions suboptimal for one component, ontogenetic differences between components resulted in positive mixing effects on grain yield since the yield proportion of the accompanying partner increased more than proportionally. In several instances, yield proportions shitted without leading to mixing effects. In some experiments and/or mixtures mixing effects could not be observed at all.     

DROUGHT STRESS: Soil Water Availability Alters the Inter‐ and Intra‐Cultivar Competition of Three Spring Wheat Cultivars Bred in Different Eras

Competition for water generates a classic aspect of the tragedy of the commons, the ‘race for fish’, where crops must allocate more resource to acquisition of the limiting resource than is optimal for crop yield allocation. A pot experiment using a simple additive (target–neighbour) design was conducted to examine the above‐ground and below‐ground growth of three spring wheat (Triticum aestivum L.) cultivars when grown alone and in mixtures at three levels of water availability. The effects of competition and water availability were compared by observing patterns of growth, biomass allocation and below‐ground outcomes. Competitive interactions were investigated among cultivars ‘HST’, ‘GY602’ and ‘LC8275’, target plant of each cultivar grown without neighbouring plants are referred to herein as control plant and one target plant of each cultivar sown surrounded either by same or another cultivar as intra‐ or inter‐cultivar competition. Competitive ability was assessed as the response ratio (lnRR) between the target plant surrounded by six other plants and the target plant in isolation. Our results showed that the cultivar ‘HST’, released over a century ago, produced a higher biomass and grain yield than the more recently released cultivars ‘LC8275’ and ‘GY602’ when grown as isolated plants with sufficient water supply. However, competition for resources from neighbours led to target plant biomass and grain yield being significantly reduced relative to controls in all three cultivars, particularly in ‘HST’. When subjected to intra‐cultivar competition, the two recently released cultivars ‘LC8275’ and ‘GY602’ had higher grain yields and water use efficiency for grain than ‘HST’ in all three water regimes. The landrace ‘HST’ had better and significantly linear relationships between biomass and biomass allocation, root length and specific root length, whereas the recent and modern cultivars had much more water‐related species‐specific changes in root morphology and allocation patterns. These results suggest that crop traits that influence competitive ability, such as biomass allocation to roots and root plasticity in response to drought have changed in modern wheat cultivars because of breeding and selection.     

Yield Comparison of Within Row Mixtures, Between Row Mixtures, and Composites of Spring Faba Bean Cultivars

The performance of three spring faba bean ( Vicia faba L.) cultivars Stella, Danas, and Minden in monocultures were compared with mixtures of Stella + Minden, and Danas + Minden sown as within row mixtures, alternate row mixtures, and as composites.
Mixtures of both cultivar combinations, whether mechanical or composites, had net increases in seed yield per plot ranging from 10.5 % to 20 % above the means of the component cultivars grown in monoculture. Cultivars grown in mixtures in alternate rows had slightly greater seed yield than when they were grown alternately within rows. A further yield enhancement was obtained from growing composites.
Data for total plant dry weight were similar to those for seed yield. The number of podded nodes per plant was the major yield component responsible for the increased yields of the component cultivars in mixtures. The ecological aspects of these results are discussed.     

Tropospheric ozone pollution reduces the yield of African crops

Northern, Southern and Equatorial Africa have been identified as among the regions most at risk from very high ozone concentrations. Whereas we know that many crop cultivars from Europe, north America and Asia are sensitive to ozone, almost nothing is known about the sensitivity of staple food crops in Africa to the pollutant. In this study cultivars of the African staple food crops, Triticum aestivum (wheat), Eleusine coracana (finger millet), Pennisetum glaucum (pearl millet) and Phaseolus vulgaris (bean) were exposed to an episodic ozone regime in solardomes in order to assess whether African crops are sensitive to ozone pollution. Extensive visible leaf injury due to ozone was shown for many cultivars, indicating high sensitivity to ozone. Reductions in total yield and 1,000-grain weight were found for T. aestivum and P. vulgaris, whereas there was no effect on yield for E. coracana and P. glaucum. There were differences in sensitivity to ozone for different cultivars of an individual crop, indicating that there could be possibilities for either cultivar selection or selective crop breeding to reduce sensitivity of these crops to ozone.