Soybean maize strip intercropping:A solution for maintaining food security in China

The practice of intercropping leguminous and gramineous crops is used for promoting sustainable agriculture,optimizing resource utilization,enhancing biodiversity,and reducing reliance on petroleum products.However,promoting conventional intercropping strategies in modern agriculture can prove challenging.The innovative technology of soybean maize strip intercropping(SMSI)has been proposed as a solution.This system has produced remarkable results in improving domestic soybean and maize production for both food security and sustainable agriculture.In this article,we provide an overview of SMSI and explain how it differs from traditional intercropping.We also discuss the core principles that foster higher yields and the prospects for its future development.

Maize-soybean strip intercropping： Achieved a balance between high productivity and sustainability

Intercropping is one of the most vital practice to improve land utilization rate in China that has limited arable land resource. However, the traditional intercropping systems have many disadvantages including illogical field lay-out of crops, low economic value, and labor deficiency, which cannot balance the crop production and agricultural sustainability. In view of this, we developed a novel soybean strip intercropping model using maize as the partner, the regular maize-soybean strip intercropping mainly popularized in northern China and maize-soybean relay-strip intercropping principally extended in southwestern China. Compared to the traditional maize-soybean intercropping systems, the main innovation of field lay-out style in our present intercropping systems is that the distance of two adjacent maize rows are shrunk as a narrow strip, and a strip called wide strip between two adjacent narrow strips is expanded reserving for the growth of two or three rows of soybean plants. The distance between outer rows of maize and soybean strips are expanded enough for light use efficiency improvement and tractors working in the soybean strips. Importantly, optimal cultivar screening and increase of plant density achieved a high yield of both the two crops in the intercropping systems and increased land equivalent ratio as high as 2.2. Annually alternative rotation of the adjacent maize-and soybean-strips increased the grain yield of next seasonal maize, improved the absorption of nitrogen, phosphorus, and potasium of maize, while prevented the continuous cropping obstacles. Extra soybean production was obtained without affecting maize yield in our strip intercropping systems, which balanced the high crop production and agricultural sustainability.

The Ecological Effects of Young Elm Trees Belt-Pumpkin Strip Intercropping System at the Agro-Pastoral Ecotone in Northern China

Young elm trees belt-pumpkin strip intercropping was studied to solve the actual problem of resource losses in the large barren area resulted from reconverting cultivated land into forest in the agro-pastoral ecotone in northern China. The final objective was to realize effective utilization of the barren land with both ecological improvement and economic development. Field experiments were conducted together with laboratory analysis. The results indicated that the soil moisture level was remarkably increased in young elm trees belt-pumpkin strip intereropping because the pumpkin vines covered the gap between pumpkin planting-furrow and elm trees belt. The water use efficiency of the intercropping system was increased by 23.7-163.3% as compared with the single cropping. Elm trees belt-pumpkin strip intercropping changed the sequential succession trend of the grasses growing in the gap of the pumpkin planting-furrow. The annual grasses become the dominant vegetation. The nutritive value as fodder and yield of the annual grasses were also increased remarkably. The biomass of pumpkin, elm trees and grasses under intercropping increased by 24.4, 28.4 and 144.4%, respectively, as compared with those under single cropping. The land use efficiency was increased by 132%. It was also indicated that the soil erosion from the intercropping land was not increased due to pumpkin plantation. The differences in the soil erosion among intercropped area, elm trees belt and pumpkin strip with single cropping were not remarkable. Therefore, it was concluded that young elm trees belt-pumpkin strip intercropping is an effective way to utilize the barren land between the young elm trees belt and realize synergistic enhancement of ecological benefit and economic profit.

Maize-legume intercropping promote N uptake through changing the root spatial distribution,legume nodulation capacity,and soil N availability

Legume cultivars affect N uptake,component crop growth,and soil physical and chemical characteristics in maize-legume intercropping systems.However,how belowground interactions mediate root growth,N fixation,and nodulation of different legumes to affect N uptake is still unclear.Hence,a two-year experiment was conducted with five planting patterns,i.e.,maize-soybean strip intercropping(IMS),maize-peanut strip intercropping(IMP),and corresponding monocultures(monoculture maize(MM),monoculture soybean(MS),and monoculture peanut(MP)),and two N application rates,i.e.,no N fertilizer(N-)and conventional N fertilizer(N+),to examine relationships between N uptake and root distribution of crops,legume nodulation and soil N availability.Results showed that the averaged N uptake per unit area of intercrops was significantly lower than the corresponding monocultures.Compared with the monoculture system,the N uptake of the intercropping systems increased by 31.7-45.4%in IMS and by 7.4-12.2%in IMP,respectively.The N uptake per plant of intercropped maize and soybean significantly increased by 61.6 and 31.8%,and that of intercropped peanuts significantly decreased by 46.6%compared with the corresponding monocultures.Maize and soybean showed asymmetrical distribution of roots in strip intercropping systems.The root length density(RLD)and root surface area density(RSAD)of intercropped maize and soybean were significantly greater than that of the corresponding monocultures.The roots of intercropped peanuts were confined,which resulted in decreased RLD and RSAD compared with the monoculture.The nodule number and nodule fresh weight of soybean were significantly greater in IMS than in MS,and those of peanut were significantly lower in IMP than in MP.The soil protease,urease,and nitrate reductase activities of maize and soybean were significantly greater in IMS and IMP than in the corresponding monoculture,while the enzyme activities of peanut were significantly lower in IMP than in MP.The soil available N of maize and soybean was significantly greater increased in IMS and IMP than in the corresponding monocultures,while that of IMP was significantly lower than in MP.In summary,the IMS system was more beneficial to N uptake than the IMP system.The intercropping of maize and legumes can promote the N uptake of maize,thus reducing the need for N application and improving agricultural sustainability.

Seedling defoliation of cereal crops increases peanut growth and yield in an intercropping system

Intercropping cereals and legumes is practiced widely in the world for improving yields and economic benefits. Shorter legume crops in intercropping are shaded by taller cereals, substantially reducing legume growth and yield. Reducing shade in intercropping by shortening the plant height of cereals by seedling defoliation has been proposed as a practical approach to increase crop yields and land productivity. A two-year field experiment was conducted to investigate the effect of defoliation of cereal crops at seedling stage on the growth and yield of peanut(Arachis hypogaea L.) intercropped with corn(Zea mays L.) or millet(Setaria italica L.). In comparison with non-defoliation controls, defoliation reduced final plant height by 29 cm on average for corn and 18 cm for millet. Photosynthetically active radiation on peanut in intercropping systems with corn or millet intercropping was respectively 27.0% and 22.8% higher than those in controls, significantly improving the light environment of intercropped peanut. Net photosynthetic rates of peanut were on average 25.5% higher in corn and peanut intercropping and 19.6% higher in millet and peanut intercropping than those in non-defoliation controls. Total biomass of intercropped peanut increased owing to increased root growth. Across two years, yield of peanut intercropped with corn was 27.7% and with millet 32.8% higher than those of controls. Defoliation of cereal crops did not affect corn yield but significantly decreased millet yield by 24.5%. Our results suggest that applying seedling defoliation in intercropped corn could increase peanut yield without compromising corn yield in an intercropping system.

不同带宽行比对玉米/大豆带状间套作群体产量和氮素效率的影响

为明确玉米/大豆带状间套作的最优配置,大田试验条件下,以单作玉米(MM)和单作大豆(MS)为对照,设置5种不同带宽行比:2 m带宽玉豆行数比为2∶2(T1)、2.4 m带宽玉豆行数比为2∶3(T2)、2.4 m带宽玉豆行数比为2∶4(T3)、2.8 m带宽玉豆行数比为2∶3(T4)、2.8 m带宽玉豆行数比为2∶4(T5),研究不同带宽行比对玉米/大豆带状间套作群体产量和氮素利用效率的影响。结果表明,玉米籽粒产量总体上随着带宽增加呈现逐渐减少的趋势,大豆籽粒产量总体上随着带宽增加呈现逐渐增加的趋势;相同带宽条件下,随着玉米大豆行比增加,玉米籽粒产量下降,大豆籽粒产量增加;玉米和大豆的植株氮素吸收利用效率变化规律与籽粒产量基本相一致。与对照相比,T2有提高玉米和大豆的收获指数,增加氮素在玉米和大豆籽粒的分配比例、降低在茎秆的分配比例的趋势。综合产量、经济效益以及群体氮素吸收、分配和利用效率的表现,2.4 m带宽下种植2行玉米3行大豆为鄂西南山区玉米/大豆的最优间套作模式。

宽幅条播对燕麦间作箭筈豌豆产量及种间关系的影响

为明确宽幅条播对燕麦‖箭筈豌豆间作系统生产力的影响,在常规条播和宽幅条播两种播种方式下设置燕麦单作、箭筈豌豆单作及燕麦‖箭筈豌豆间作三种种植方式,比较分析了不同处理间作物产量、种间关系及燕麦产量构成因素的差异。结果表明,与单作相比,间作燕麦的饲草及籽粒产量显著提高,增幅分别为24.25%~32.77%和27.44%~32.69%,而间作箭筈豌豆的饲草及籽粒产量降低为7.16%~8.08%和2.80%~5.48%。宽幅条播可提高燕麦及箭筈豌豆产量,宽幅条播间作饲草和籽粒产量的土地当量比较常规条播间作分别提高0.03和0.06。在间作中,燕麦的侵占力大于0,实际产量损失大于1,竞争比率大于1,且燕麦的相对拥挤系数大于箭筈豌豆,说明燕麦在间作系统中处于竞争优势。间作燕麦穗数、穗粒数和穗重较单作显著提高,平均增幅分别为24.23%、14.84%和17.43%,其中宽幅条播间作处理的穗粒数、公顷穗数和穗重均显著高于其他处理。由此可见,宽幅条播下通过与箭筈豌豆间作,可提高燕麦生产力和土地资源利用效率。

南充市大豆玉米带状复合种植调研报告

为了解南充市大豆玉米带状复合种植现状,文章以南充市南部县与西充县多个大豆玉米带状复合种植示范区为调研对象,对调研区的基本种植情况、存在问题进行调研,提出促进南充市大豆生产发展建议,包括优选良种,加强田间管理;推进西南丘区小型智能农机装备研发进程;提供政策扶持,加快大豆生物育种步伐,旨在为提升南充大豆单产水平提供参考,助力南充市大豆产业发展。

饲用高粱、青贮玉米带状间作苗后除草剂筛选及安全性评价

对饲用高粱、青贮玉米带状间作地用40%甲磺草胺悬乳剂、48%麦草畏水剂及25%二氯喹啉酸悬乳剂3种除草剂单剂和复配使用的杂草防除效果和安全性进行评价。结果表明,40%甲磺草胺悬乳剂、48%麦草畏水剂和25%二氯喹啉酸悬乳剂均对间作饲用高粱和青贮玉米具有良好的安全性,且以40%甲磺草胺悬乳剂540 g·hm^(-2)+48%麦草畏水剂450 m L·hm^(-2)+25%二氯喹啉酸悬乳剂630 g·hm^(-2)复配制剂除草效果表现最优,在饲用高粱3~4叶期喷施,15 d对田间总草(田间全部杂草)防除效果可达93.64%,30 d防除效果为92.80%。

胡麻间作模式对作物养分吸收利用及产量的影响

为明确不同胡麻间作系统中作物养分吸收利用对产量贡献的差异,本研究采用田间二因素随机区组试验设计,设置两种间作类型:胡麻||玉米间作(F||M)、胡麻||大豆间作(F||S), 3种带型配置[4∶2 (S1)、6∶3 (S2)和8∶4(S3)],以单作为对照,共计9组处理,比较分析了两种间作系统中不同带型配置的间作优势以及成熟期养分吸收量和利用效率对间作优势的贡献。结果表明:与单作相比,间作提高了作物生物产量和籽粒产量,胡麻||玉米间作系统显著高于胡麻||大豆间作,且在8∶4行比配置下达到最大值;两种间作系统中土地当量比(LER)均大于1,具有间作产量优势。胡麻||玉米间作系统中,植株氮、磷和钾养分吸收总量比相应单作提高12.15%~50.38%、44.79%~67.29%和3.90%~25.75%,氮素利用效率高出单作73.20%~78.36%;氮、磷和钾吸收因子对LER的贡献分别为1.33~2.10、1.76~2.08和1.11~1.53,利用因子的贡献分别为-0.30~-0.12、-0.42~-0.25和-0.10~0.07。胡麻||大豆间作系统中,植株氮、磷和钾养分吸收总量比相应单作提高6.86%~60.06%、11.97%~59.21%和7.34%~65.30%,氮素利用效率高出单作48.77%~71.74%;氮、磷和钾吸收因子对LER的贡献分别为1.17~2.13、1.20~2.10和1.15~2.15,利用因子的贡献分别为-0.53~-0.30、-0.46~-0.15和-0.52~-0.03。综合分析认为,本研究中8行胡麻4行玉米间作带型能提高作物养分吸收利用能力,增加间作系统作物产量,其间作优势主要来源于养分吸收量的增加,而非利用效率的改变。

化控对玉米带状间作大豆主茎分枝光合特性、物质积累及产量的影响

为充分挖掘化控技术对带状间作系统中大豆的增产潜力,本研究以大豆-玉米带状间作为研究对象,以南豆25为试验材料,通过在大豆4节期(V4)叶面喷施不同植物生长调节剂[抑芽丹(MH)、吲哚-3-乙酸(IAA)、6-苄氨基嘌呤(6-BA)、24-表油菜素内酯(EBR)、三碘苯甲酸(TIBA)、烯效唑(S3307)、胺鲜酯(DTA-6)]及清水(CK),探究调节剂对大豆主茎和分枝结构上的光合特性、干物质积累分配及产量的影响。结果表明,调节剂处理提高了带状间作大豆主茎和分枝叶片SPAD值、净光合速率、气孔导度和蒸腾速率,EBR、S3307和DTA-6处理下大豆的叶面积指数、干物质积累量和群体产量显著高于CK。各调节剂中以DTA-6协调主茎与分枝生长关系的效果最好,该处理下盛荚期(R4)大豆主茎和分枝的干物质积累量分别较CK增加15.62%和30.24%,完熟期分枝荚果分配率最高。产量结果也表明,DTA-6处理下分枝粒数和百粒重达到最大,使大豆群体产量较CK提高26.01%~32.61%。综上,DTA-6能够改善带状间作大豆主茎和分枝叶片光合特性,促进干物质积累分配及产量形成。本研究为化控在带状间作大豆中的推广应用提供了理论参考与技术支撑。

大豆-玉米带状复合种植模式下草地贪夜蛾的生存适应性和危害性

【目的】研究草地贪夜蛾(Spodoptera frugiperda)对大豆和玉米的取食代谢特性和迁移扩散行为,明确草地贪夜蛾在大豆-玉米带状复合种植模式下的取食规律和潜在危害风险。【方法】供试寄主植物为江苏省大豆-玉米带状复合种植推荐品种徐豆18和江玉877,室内测定大豆叶片和玉米叶片对草地贪夜蛾的取食趋性、生长发育、产卵量、产卵选择性、消化酶活性及消化代谢的影响。田间接种卵块并调查玉米-大豆“2+4”模式间作下草地贪夜蛾随时间的迁移距离和范围,根据迁移动态评估其在该种植模式下的潜在危害风险。【结果】草地贪夜蛾对玉米叶片表现出明显的取食趋向性,选择取食玉米叶片个体占63.89%,为选择取食大豆叶片个体数的1.77倍,差异显著。草地贪夜蛾取食大豆叶片和玉米叶片均能完成世代发育,但取食玉米叶片的草地贪夜蛾幼虫发育历期为14.82 d,较取食大豆叶片的幼虫发育历期缩短2.54 d,单雌产卵量为679.50粒,较取食大豆叶片增加26.58%,差异显著。成虫产卵主要选择玉米叶片,平均卵块数和单雌着卵量为5.67块和521.67粒,分别为大豆的1.70和2.04倍,差异显著。取食大豆叶片的草地贪夜蛾脂肪酶活性为9.84 U·g^(-1),较取食玉米叶片的脂肪酶活性6.47 U·g^(-1)显著提高,而两者的蛋白酶和淀粉酶活性无显著差异。取食大豆叶片的草地贪夜蛾近似消化率为63.40%,较取食玉米叶片的近似消化率69.26%显著降低,但两者在食物利用率、食物转化率和相对生长率方面无显著差异。田间接种卵块后调查发现玉米-大豆“2+4”模式间作下,草地贪夜蛾主要在玉米上扩散,于玉米种植行内“纵向迁移”,未扩散到相邻的大豆植株上。【结论】草地贪夜蛾对大豆和玉米的取食适应和产卵选择具有一定的差异,相较于大豆,草地贪夜蛾对玉米表现出较强的选择趋向性和利用能力,在玉米-大豆“2+4”带状种植模式下,草地贪夜蛾以危害玉米为主。因此,在实际生产中,应加强对草地贪夜蛾的监测和防治工作,特别是在玉米生长的关键时期采取有效的防治措施,以降低其危害风险。

种植密度对北疆灌区带状间作青贮玉米-大豆物质积累及产量的影响

【目的】为明确北疆灌区青贮玉米-大豆带状间作最佳密度配置,挖掘群体生物产量潜力。【方法】采用二因素裂区试验设计,主因素为玉米密度:A1、A2、A3(2021年:6.75、8.25、9.75万株/hm^(2);2022年:9、10.5、12万株/hm^(2)),副因素为大豆密度:B1、B2、B3 (2021年:12、15、18万株/hm^(2);2022年:15、18、21万株/hm^(2)),拟分析不同种植密度对带状间作玉米大豆物质积累和群体生物产量的影响。【结果】玉米密度从6.75万株/hm^(2)增至12万株/hm^(2),玉米单株干物质平均下降35.46%,花前积累量平均下降25.42%,达到最大生长速率时间(T_(max))、最大生长速率生物量(W_(max))和活跃生长期(P)平均下降10.99%、39.48%和1.78%。玉米生物产量、干物质日积累量、花后积累量、最大生长速率(G_(max))和平均生长速率(G_(mean))随玉米密度增加呈先增后减趋势,均在10.5万株/hm^(2)密度达到最大。随玉米密度和大豆密度增加,大豆单株干物质、花前积累量、W_(max)、G_(max)和G_(mean)呈下降趋势,花后积累量、T_(max)和P呈上升趋势。2022年A2B3处理带状间作群体产量最高,为64.99 t/hm^(2),较A1B1增产11.98 t/hm^(2),对群体干物质积累量(Y)和种植密度(A、B)回归分析得出,当A=10.84万株/hm^(2),B=19.41万株/hm^(2),Y取得极大值24.87 t/hm^(2)。【结论】玉米10.5万株/hm^(2)和大豆21万株/hm^(2)密度带状间作群体生物产量最大,可为北疆灌区带状间作玉米大豆适宜种植密度提供参考。

施氮与种间距离下大豆/玉米带状套作作物生长特性及其对产量形成的影响

为明确施氮和种间距离下套作作物生长特性及其对产量形成的影响。本文以大豆/玉米带状套作系统为研究主体,探究不同氮水平(施氮与不施氮)与种间距离(玉豆间距30、45、60和75 cm、单作100 cm)下作物生长率、干物质积累与分配及产量差异,并对作物干物质积累过程进行拟合,综合分析作物生长规律和产量效益。结果表明:玉米生长率在抽雄期至乳熟期达最大,不施氮下以间距30 cm(MS30)最高,较玉米单作(MM100)高出34.99%。套作大豆生长率在初花期前显著低于单作(SS100),而初花期后高于SS100,以间距60cm(MS60)最高,盛花期—盛荚期在不施氮下较SS100高出78.91%。Logistic方程可较好的拟合玉米、大豆的干物质积累过程,且R2均在0.95以上。与不施氮相比,施氮推迟了玉米干物质积累高峰,提高了干物质积累量;套作大豆生育前期干物质积累慢于单作,而生育后期间距45cm(MS45)、MS60干物质积累逐渐与单作持平甚至超过单作。施氮提高了玉米籽粒干物质分配率而显著提高产量,2年间玉米产量分别提高10.05%、40.90%。随种间距离增加套作大豆产量呈先增后减趋势,以MS60最高,MS30最低,MS60两年间在不施氮与施氮下较MS30分别平均高出23.88%、31.77%。套作下土地当量比均在1.35以上,其中以施氮下MS60最大(1.89)。适宜的种间距离(间距60 cm)可实现套作下玉米和大豆协同生长,提高作物生长率、促进干物质积累与分配、提高系统产量和土地当量比。

带状复合种植模式下玉米大豆性状表现与综合效益分析

于2022年引进了5个玉米品种,与鄂豆10号大豆带状复合种植,观察玉米和大豆的相关性状,筛选出适宜的玉米品种,分析综合效益。结果表明:各复合种植模式中,以MY73+鄂豆10号处理的玉米单产、总产、总产值最高,分别为6 655 kg/hm^(2)、8 030 kg/hm^(2)、26 103元/hm^(2);玉米品种MY73在试验中表现为产量最高、株高较矮、综合抗性好,是玉米大豆复合种植模式中较适宜的品种。

鲜食花生‖鲜食玉米高值化生产技术

在玉米花生带状复合种植技术的基础上,利用鲜食玉米生育期短、鲜食花生提前收获的特点,创新发展了鲜食花生‖鲜食玉米高值化生产技术,该技术在黄淮地区可以实现鲜食花生‖鲜食玉米一年两季种植。本文通过分析该技术在适宜模式、品种和机械的选择以及抢墒播种、水肥管理、病虫草防控、旺长调控、收获与储运等环节的关键要点,及其主要优势和应用前景,以期为该技术在粮油主产区推广应用提供技术支撑。

长江流域田间配置对玉米-大豆带状复合种植群体产量和气候资源利用效率的影响

【目的】探究长江流域各地区群体产量效益与光、温、水资源利用效率最优的生产单元和行比配置。【方法】在长江流域粮食主产区,以当地主栽的带状复合种植模式为主,四川与湖北地区采用春玉米夏大豆带状套作模式,湖南与江西地区采用春玉米春大豆带状间作模式,江苏地区采用鲜食玉米鲜食大豆带状套作模式,以单作玉米(MM)与单作大豆(SS)为对照,设置5个不同的玉米-大豆带状间套作田间配置:生产单元2 m行比2∶2(T1)、生产单元2.4 m行比2∶3 (T2)、生产单元2.4 m行比2∶4 (T3)、生产单元2.8 m行比2∶3 (T4)、生产单元2.8 m行比2∶4 (T5)。【结果】3年试验结果表明各地区玉米产量总体呈现随生产单元宽度增加下降的趋势,大豆产量呈现为相反趋势,群体产量呈现随生产单元宽度增加下降的趋势。不同区域玉米-大豆带状复合种植均表现出明显的间套作优势,土地当量比在不同地区之间尤以长江上游的四川、湖北生态区表现突出,最高达1.64。长江上中下游各田间配置群体产量效益与光温水资源利用均大幅高于单作大豆,在生产单元2 m,行比2∶2的田间配置下相较单作玉米,长江上游四川与湖北试验点平均经济效益分别提高了39.20%、39.34%,光温水生产效率分别提高了31.48%、19.42%、13.85%(四川)和56.90%、41.45%、42.89%(湖北),长江下游江苏试验点3年平均经济效益提高22.22%,光温水生产效率分别提高22.09%、13.16%、14.41%。长江中游湖南试验点在生产单元2.4 m,行比2∶3的田间配置下3年平均经济效益与光温水生产效率较单作玉米分别提高13.07%、13.86%、7.77%和6.45%,长江中游江西试验点在生产单元2.4 m,行比2∶4的田间配置下3年平均经济效益与光温水生产效率较单作玉米无显著差异。【结论】综合3年群体产量效益与资源利用率及主成分分析表明,长江上游(四川、湖北)与长江下游(江苏)玉米-大豆带状套作区应实行生产单元2 m,行比2∶2的田间配置,长江中游(湖南、江西)带状间作区可分别采用生产单元2.4 m,行比2∶3与生产单元2.4 m,行比2∶4的田间配置。

玉米-大豆带状套作对土壤肥力的影响

【目的】明确玉米大豆带状套作对土壤肥力、酶活性、团聚体含量的影响以及作物产量的变化。【方法】以“登海605”为供试玉米品种,以“南豆12”为供试大豆品种,设置玉米-大豆带状套作、玉米单作和大豆单作3个处理,系统研究不同处理对土壤有机质、全氮、全磷和有效磷、全钾和速效钾含量,pH、容重,脲酶、蔗糖酶、酸性磷酸酶、硝酸还原酶活性、团聚体含量和作物产量的影响。【结果】玉米-大豆带状套作显著提高了玉米和大豆带土壤的有机质、有效磷、速效钾等养分含量,其中玉米带增幅分别为18.1%、14.9%和21.8%,大豆带有机质和速效钾增幅分别为17.7%和34.9%,而有效磷增幅较小且不显著,并保持了全氮、全磷、全钾含量和pH的稳定。玉米带土壤容重显著下降3.3%,大豆带则显著增加4.7%。带状套作显著提高了土壤蔗糖酶和脲酶的活性,玉米带增幅为16.3%和20.5%,大豆带增幅为133.7%和66.2%,酸性磷酸酶和硝酸还原酶活性保持稳定。带状套作促进了大粒径团聚体的形成,套作玉米和大豆带>2 mm团聚体分别显著提高18.8%和22.2%,其他各粒级的小团聚体不同程度下降。带状套作玉米较单作千粒重、穗粒数、有效株数和产量均无显著差异。带状套作大豆有效株数、单株粒数分别较单作显著下降12.9%、26.5%,百粒重无显著差异,最终使大豆产量达到单作的60.9%。【结论】玉米-大豆套作模式提高了土壤肥力,显著增加了有机质、速效钾、有效磷等的含量,维持了土壤中全氮、全磷、全钾含量和pH的稳定,并显著提高了土壤脲酶和蔗糖酶的活性,从而有利于土壤养分转化和植物吸收利用。带状套作还促进微小团聚体向稳定的大团聚体转化,从而提高了土壤的通透性和保水保肥能力,一定程度上影响土壤的化学性质,满足了玉米和大豆生长需要。因此,玉米-大豆带状套作可以改善土壤的化学性质和物理性质,提高土壤肥力,保持与单作相当的玉米产量,并能额外收获相当于单作产量60.9%的大豆。

种植密度对北疆灌区大豆-玉米带状间作混合青贮产量和作物抗倒特性的影响

【目的】针对北疆灌区光照资源丰富但青贮种植单一的问题,利用大豆-玉米带状复合种植优势,在北疆灌区通过设计大豆-玉米不同种植密度来调控作物青贮产量,为当地青贮间作适宜密度栽培提供参考。【方法】设置3个玉米种植密度:9万株/hm^(2)(M1)、10.5万株/hm^(2)(M2)和12万株/hm^(2)(M3)。3个大豆种植密度:15万株/hm^(2)(S1)、18万株/hm^(2)(S2)和21万株/hm^(2)(S3),阐明不同密度处理下作物农艺性状、群体光合有效辐射、抗倒伏特性和青贮产量。【结果】玉米种植密度从9万株/hm^(2)增至12万株/hm^(2),茎秆穿刺强度平均降低17.30%~25.72%,倒伏率平均增加51.13%~55.27%,叶面积指数(LAI)平均增加8.00%~22.82%,光合势(LAD)平均增加10.49%~29.49%,产量呈先升后降趋势,在10.5万株/hm^(2)密度下获得最大值,大豆株高和倒伏率随玉米种植密度增加呈上升趋势,大豆冠层透光率、茎粗和抗折力呈下降趋势,LAI和LAD呈先升后降趋势。在玉米低、中和高密度处理下,大豆高密度间作与低、中密度间作相比,抗折力分别降低18.71%~29.83%、19.68%~36.94%和20.48%~31.74%,倒伏率分别增加9.77%~48.50%、9.82%~66.24%和2.25%~35.80%。随大豆种植密度增加,大豆LAI、LAD和产量增加,倒伏率显著下降。M2S3处理间作系统混合青贮产量最高,为64 981.84 kg/hm^(2),较M2S1处理增产2.81%。【结论】玉米10.5万株/hm^(2)搭配大豆21万株/hm^(2)间作种植有利于提高混合青贮产量,可为北疆灌区青贮大豆-玉米带状复合种植适宜播种密度种植提供参考依据。

宁夏引黄灌区不同带距及水肥处理对玉米大豆间作系统光合特性和产量的影响

为明晰玉米大豆间作系统对不同带距和水肥供给条件的响应特征及其效应,在宁夏引黄灌区选取玉米-大豆2∶4间作种植模式,研究带距(A)、灌溉定额(W)、施肥量(F)对玉米、大豆及间作系统的生理指标、净同化率、叶面积指数和产量的影响,为玉米大豆带状复合种植技术推广应用提供技术支持。结果显示:A对玉米生理指标的影响主要在拔节期和灌浆期(贡献率分别为75.6%~83.7%、52.4%~81.3%),W在抽穗期(贡献率为91.4%~92.5%);A对大豆生理指标的影响主要在开花期(贡献率为97.9%~99.3%),W在结荚期(贡献率为70%)。T6(A2W3F1)处理有利于玉米净同化率(NAR)和叶面积指数(LAI)升高,在试验的高水高肥对大豆LAI呈负相关。三因素对系统产量和经济效益影响显著,排序为W>A>F;A和W的3个水平对玉米产量和系统产量均有显著影响,且A2>A3>A1,W3>W2>W1,F水平对大豆产量影响不显著;各因素水平对系统经济效益贡献率为A2>A3>A1、W3>W2>W1和F1>F3>F2,A2的效益比A1高25.2%、W3比W1高32.3%、F1比F2高11.2%。