Assessing the Efficacy of Wheat-Soybean Based Intercropping System at Different Plant Densities in Bambili, Cameroon

Wheat is one of the most important cereals in the world, serving as a staple for millions globally. In the wake of the geopolitical crisis between Russia and Ukraine, it has become incumbent for many countries to invest in wheat production. Improving cropping systems for wheat production is paramount. Intercropping cereals with legumes has tremendous advantages. Therefore, this study was designed to optimize wheat production by intercropping it with soybean at different densities. Between March and August 2023, a randomized complete block design trial was conducted in Bambili, North West of Cameroon with treatments T1 (wheat monocrop at 200,000 plants ha−1), T2 (soybean monocrop at 250,000 plants ha−1), T3 (200,000 wheat and 125,000 soybean ha−1), T4 (100,000 wheat and 250,000 soybean ha−1), T5 (200,000 wheat and 250,000 soybean ha−1) and T6 (100,000 wheat and 125,000 soybean ha−1). Results revealed that growth parameters of wheat were not significantly influenced by monocrop or intercrop. The yield of wheat was significantly higher in the monocrop than the intercrop treatments, with slight variation amongst the intercrop treatments. Soybean yield was higher in the monocrop than in the intercrop, with no variations amongst the intercrop treatments. Only the land equivalence ratio (LER) for T5 was greater than 1.0. The competitive ratio for T5 was 0.54 for wheat and 1.90 for soybean, comparatively lower than the other monocrop treatments. Intercropping wheat and soybean at 200,000:250,000 ratio is recommended.

Experimental analysis of a nitrogen removal process simulation of wastewater land treatment under three different wheat planting densities

Nitrogen contaminant transport, transformation and uptake simulation experiments were conducted in green house under three different planting density of winter wheat. They were Group A, planting density of 0.0208 plants/cm 2, Group B, 0.1042 plants /cm 2, and Group C, 0.1415 plants/cm 2. The capacity and ratio of nitrogen removal were different on three kinds of conditions of wastewater land treatment. From analysis of wastewater treatment capacity, wastewater concentration and irrigation intensity for Group C were suitable and nitrogen quantity added was 2 times of that for Group B, 2.6 times for Group A while nitrogen residue was only 7.06%. Hence, wastewater irrigation and treatment design with purpose of waste water treatment should select the design with maximum capacity, optimal removal ratio and least residue in soil, which was closely related to crop planting density, crop growth status and also background nitrogen quantity in soil.

Effects of Soil Improver on Wheat in Saline-Alkali Lands in the Yellow River Delta

Field experiment carried out to test the effects of soil improver on wheat yield and soil physical-chemical properties. The results indicated that soil improver could optimize soil aggregates structure, decrease soil bulk density, soil pH and soil salt content, increase soil organic matter and 1 000-grain weight, thereby enhancing wheat yield. With the increase of soil improver application amount, soil physical-chemical properties became better and wheat yield increased. However, there was no significant difference in the treatments with the application amounts of 3%, 4% and 5%. In addition, the treatment of reducing nitrogen showed no superiority in soil physical-chemical properties and wheat yield, indicating that sufficient nitrogen was essential for the growth of wheat.

陇东旱地冬小麦品种抗旱性鉴定

为研究陇东特殊干旱气候条件下抗旱育种的进展与现状,选取近20 a陇东旱地选育的14个冬小麦新品种(系)为材料,以籽粒产量抗旱指数等为全生育期抗旱性鉴定指标,在旱棚进行全生育期干旱胁迫试验。结果表明,陇育4号和宁麦5号抗旱指数在1.100~1.299范围内,抗旱级别为2级;陇育7号和陇鉴387抗旱指数在0.700~0.899范围内,抗旱级别为4级;其余10个材料抗旱指数在0.900~1.099范围内,抗旱级别为3级。抗旱性级别在2~3级的材料占85.7%。产量性状主因子分析发现,抗旱级别为2级的陇育4号和宁麦5号,在干旱胁迫下有效穗数、穗粒数和千粒重无明显变化;抗旱级别为4级的陇育7号和陇鉴387,在干旱胁迫下有效穗数、穗粒数和千粒重均减幅较大;抗旱级别为3级的其余10个材料在干旱条件下,其产量性状三要素有效穗数、穗粒数、千粒重中只有一项发生变化,没有两项叠加变化。

我国主要粮食产区土壤有效态钙镁硫的变化特征及其对作物产量的影响

中量元素钙、镁、硫对农业生产的作用日益突出,研究土壤有效态钙镁硫的变化特征及其对作物产量的影响,可为全国和区域尺度耕地土壤中量元素管理和合理施肥提供理论依据。基于覆盖全国697个耕地质量监测点的监测数据,对比分析2016和2021年全国及六大粮食产区(东北区、华北区、西北区、西南区、长江流域和华南区)的土壤有效态钙镁硫含量的变化特征及其对主要粮食作物产量的影响。与2016年相比,2021年697个监测点的土壤交换性钙和交换性镁平均含量变化不显著,有效硫平均含量显著下降了27.3%,全国交换性钙、交换性镁和有效硫主要与土壤pH和有机质(OM)相关。六大粮食产区土壤有效态钙镁硫含量的年际变化特征有所不同。与2016年相比,2021年东北区交换性钙和镁含量分别显著增加了25.5%和52.4%,主要与pH相关;有效硫含量显著下降了47.8%,主要与速效钾相关。华北区交换性钙含量显著下降了11.8%,主要与pH相关。西北区交换性钙、镁和有效硫含量分别显著下降了64.0%、54.0%和30.4%,钙主要与总钾相关,镁主要与全磷相关,硫与土壤其他理化性质不存在显著相关。西南区有效硫含量显著下降了30.0%,主要与pH和OM相关。长江流域交换性镁和有效硫含量分别显著下降了52.0%和15.7%,主要与pH和OM相关。华南区3种有效态中量元素含量变化不显著,三者主要与pH和OM相关。在全国尺度下,水稻产量与土壤交换性钙和镁含量呈显著正相关,玉米产量与交换性镁和有效硫含量呈显著正相关,小麦产量则与3种中量元素不存在显著相关性;当pH≤7.0时,小麦产量与交换性钙和镁含量呈显著正相关,当pH>7.0时则不存在显著相关性;无论土壤呈酸性还是碱性,小麦产量均与有效硫含量不存在显著相关性。综上,2016—2021年的5年间,我国耕地土壤交换性钙、镁含量变化不显著,有效硫含量显著降低,这些中量元素主要与土壤pH和OM相关。六大粮食产区中量元素含量变化特征和影响因素及其对主要粮食作物产量的影响存在较大差异,针对性施用中量元素肥料有助于提升区域粮食产量。

荧光假单胞杆菌拌种在旱地小麦种植中的应用效果研究

为探讨沧州地区旱地冬小麦种植中荧光假单胞杆菌拌种技术应用的可行性,以沧麦6005为试验材料开展田间比较试验,探究荧光假单胞杆菌拌种对旱地冬小麦生长、产量与经济效益的影响。结果表明,荧光假单胞杆菌拌种可促进旱地冬小麦冬期前根系发育,有效防治小麦纹枯病和茎基腐病等。用3000~6000 mL/hm^(2)荧光假单胞杆菌拌种300 kg/hm^(2),小麦产量较清水拌种(300 kg/hm^(2))增加31.68%~33.76%,增产效果优于4500 mL/hm^(2)噻虫·咪鲜胺拌种300 kg/hm^(2),投入产出比较高,经济效益较大。荧光假单胞杆菌拌种可提高旱地冬小麦的产量与经济效益,建议在以沧州生态类型区为代表的黑龙港东部旱地冬小麦种植中推广应用。

Nitrate Accumulation in Soil Profile of Dry Land Farming in Northwest China

A long-term fertilizer experiment on dry land of the Loess Plateau, northwest China, has been conducted since 1984 to study the distribution and accumulation of NO3-N down to a depth of 400 cm in the profile of a coarse-textured dark loessial soil after continuous winter wheat cropping. Thirteen fertilizer treatments consisted of four levels of N and P applied alone or in combination. Annual N and P (P2O5) rates were 0,45, 90, 135 and 180 kg ha-1. After 15 successive cropping cycles, the soil samples were taken from each treatment for analysis of NO3-N concentration. The results showed that NO3-N distribution in the soil profile was quite different among the treatments. The application of fertilizer N alone resulted in higher NO3-N concentration in the soil profile than the combined application of N and P, showing that application of P could greatly reduce the NO3-N accumulation. With an annual application of 180 kg N ha-1 alone, a peak in NO3-N accumulation occurred at 140 cm soil depth, and the maximum NO3-N concentration in the soils was 67.92 mg kg-1. The amount of NO3-N accumulated in the soil profile decreased as the cumulative N uptake by the winter wheat increased. Application of a large amount of N resulted in lower N recoveries in winter wheat and greater NO3-N accumulation in soil profile. NO3-N did not enter underground water in the study region; therefore, there is no danger of underground water pollution. Amount of NO3-N accumulation can be predicted by an equation according to annual N and P rates based on the results of this experiment.

河北滨海盐碱地浅层轻度咸水资源冬小麦灌溉安全利用研究

河北滨海盐碱耕地缺少灌溉水资源,该区具有丰富的浅层微/轻度咸水资源,冬小麦生长关键期适当进行微/轻度咸水灌溉能够缓解该区农田灌溉危机。本文以河北省滨海盐碱地为研究对象,选择沧州市南大港产业园区马营村为试验基地,开展浅层轻度咸水冬小麦农田灌溉试验,分析咸水灌溉对冬小麦产量和土壤盐分含量变化的影响。结果表明:1)河北滨海盐碱地浅层轻度咸水(6 g∙L^(-1))在冬小麦拔节—抽穗期进行一次600 m^(3)∙hm^(-2)的灌溉,产量能够达到旱作冬小麦的1.5倍以上,增产效果明显。2)基于暗管排水排盐工程、在雨季保持多年平均降雨量条件下,2016—2018年雨季后试验地土壤平均含盐量分别为2.86 g∙kg^(-1)、1.60 g∙kg^(-1)和1.38 g∙kg^(-1),呈现逐年降低的趋势。由此得出:河北滨海盐碱地浅层咸水资源在冬小麦灌溉方面能够实现安全利用。在此基础上,以河北滨海沧州市为例分析浅层咸水资源利用前景,从水资源量上,1~5 g∙L^(-1)的浅层微/轻度咸水资源可以满足冬小麦农田因地下水压采限采造成的至少1.7×10^(8)m^(3)灌溉水量亏缺,从耕地资源方面,扩大一年两熟种植面积,增加冬小麦种植面积约131000 hm2。研究结果可为河北滨海盐碱地咸水资源安全利用、土壤健康和粮食安全提供科学依据。

Effects of sand burial on growth and antioxidant enzyme activities of wheat(Triticum aestivum L.) in northern China

Growth and physiological responses of wheat to sand burial were studied in Horqin Sandy Land, to determine the impact on productivity and survival as well as antioxidant enzymes responses. This study consisted of one control （no sand） and four sand burial treatments： 25%, 50%, 75% and 100% of seedling height, respectively. Minor burial （25%） had no effect on wheat growth and survival; deep burial （100%） was fatal, and the others had an intermediate effect. Thus, the survival limit to sand burial was equal to seedling height. Sand burial mainly decreased shoot biomass and crop yield, but had small effects on belowground biomass. Superoxide dismutase （SOD） activity increased with time after burial in all treatments with surviving plants. Peroxidase （POD） activity increased after six days under burial, and catalase （CAT） activity de- creased after burial, but recovered after 12 days. The concentration of malondialdehyde （MDA）, a marker for oxidative stress, was low on the sixth day, but increased thereafter with burial depth. Thus, sand burial 〉25% should be avoided due to growth rate reduction leading to reduced crop yield, and even 25% burial showed physiological indicators of stress.

Optimization of sowing date and seeding rate for high winter wheat yield based on pre-winter plant development and soil water usage in the Loess Plateau,China

Sowing date and seeding rate are critical for productivity of winter wheat(Triticum aestivum L.).A three-year field experiment was conducted with three sowing dates(20 September(SD1),1 October(SD2),and 10 October(SD3)) and three seeding rates(SR67.5,SR90,and SR112.5) to determine suitable sowing date and seeding rate for high wheat yield.A large seasonal variation in accumulated temperature from sowing to winter dormancy was observed among three growing seasons.Suitable sowing dates for strong seedlings before winter varied with the seasons,that was SD2 in 2012–2013,SD3 in 2013–2014,and SD2 as well as SD1 in 2014–2015.Seasonal variation in precipitation during summer fallow also had substantial effects on soil water storage,and consequently influenced grain yield through soil water consumption from winter dormancy to maturity stages.Lower consumption of soil water from winter dormancy to booting stages could make more water available for productive growth from anthesis to maturity stages,leading to higher grain yield.SD2 combined with SR90 had the lowest soil water consumption from winter dormancy to booting stages in 2012–2013 and 2014–2015; while in 2013–2014,it was close to that with SR67.5 or SR112.5.For productive growth from anthesis to maturity stages,SD2 with SR90 had the highest soil water consumption in all three seasons.The highest water consumption in the productive growth period resulted in the best grain yield in both low and high rainfall years.Ear number largely contributed to the seasonal variation in grain yield,while grain number per ear and 1 000-grain weight also contributed to grain yield,especially when soil water storage was high.Our results indicate that sowing date and seeding rate affect grain yield through seedling development before winter and also affect soil water consumption in different growth periods.By selecting the suitable sowing date(1 October) in combination with the proper seeding rate of 90 kg ha–1,the best yield was achieved.Based on these results,we recommend that the current sowing date be delayed from 22 or 23 September to 1 October.

Effect of Industrial Sludge Application on Soil Nitrogen and Wheat Plant Response

Wazirpur industrial area of Delhi generates a huge quantity of sludge per day, which is highly acidic in nature (pH 2.7 to 4.4) and contains macronutrients, micronutrients as well as toxic metals. A pot-culture experiment was conducted by taking the two soils (JNU and Chhattarpur) amended with sludge (0%, 10%, 20%, 30%), pretreated with lime (0%, 0.5% and 1%). Two wheat seedlings were planted per pot containing 3 kg sludge amended or control soil and the experiment was carried out till harvesting (four months) in a glass house. Lime treatments enhanced the N content in wheat plant in almost all cases. Sludge and lime treatments enhanced dry weight in wheat plants grown in Chhattarpur soil and dry weight increased with time. Maximum growth was observed in 0.5 lime treated and 20% sludge amended soils. But we have to take an account about any kind of metal toxicity before disposal of this waste to land.

黄淮麦区旱肥地小麦新品种(系)苗期抗旱性初步鉴定与分类

了解黄淮麦区旱肥地小麦节水新品种系的抗旱性,有利于小麦推广和在育种中的应用。以50份近年黄淮旱肥地小麦品种系为试验材料,在15%PEG-6000(聚乙二醇)溶液模拟干旱胁迫下,测定种子发芽率、苗高、叶绿素含量的变化,并进行抗旱性评价和分类。结果表明:胁迫条件下小麦种子发芽率、苗高与其苗期抗旱性显著相关;50份材料分为4类,分别为4份高抗旱型种质(D值为0.8255~0.9980),10份抗旱型种质(D值为0.6516~0.7270),28份干旱敏感型种质(D值为0.4941~0.6354),8份干旱高敏感型种质(D值为0.3079~0.4676);相较于平均隶属函数值评价抗旱性,采用D值大小评价并结合最长距离法系统聚类分析,可以比较合理、直观地呈现分类结果。据此,实验明确了在15%PEG-6000胁迫下,发芽率、苗高可以作为评价苗期抗旱能力的主要指标;区分了50份不同品种系的抗旱性,可为抗旱节水品种选育、推广提供依据。

半干旱区旱地春小麦新品系性状比较试验

在半干旱区的会宁旱地春麦种植区,对新选育出的9个旱地春小麦新品系进行了丰产性、抗旱性、抗病性等性状鉴定。结果显示,06004-3-1、1105-7-1-8和1102-1-5-3共3个品系抗逆性强、籽粒饱满、产量高,较对照西旱2号增产2.94%以上,差异达极显著水平。其中,06004-3-1保苗、成穗率高,抗病性强,丰产性好,较对照西旱2号增产6.40%,居参试材料1位;1105-7-1-8和1102-1-5-3分别较对照西旱2号增产5.66%、2.94%,分别居参试材料2、3位。综合分析了新选育出的9个参试材料的生育期、产量、抗逆性及田间长势等,06004-3-1、1105-7-1-8共2个品系综合农艺性状表现优良,建议推荐进入区域试验,1102-1-5-3等材料继续参加品系比较试验进一步鉴定相关性状。

白洋淀流域蒸散发增加的驱动因素(英文)

白洋淀流域位于雄安新区上游,山区植被和下垫面变化、平原区农业灌溉加大了区域蒸散发,造成山区产流减少和平原区地下水超采。研究区域蒸散发(ET)时空格局的演变趋势、甄别植被、作物种植结构、城市化等对蒸散发变化的影响,对深入揭示白洋淀流域水资源枯竭的成因,建设绿色雄安“未来之城”具有重要意义。本研究基于500 m空间分辨率的PML_V2遥感蒸散产品,从像元尺度分析了2002—2018年研究区ET的变化趋势和显著性,揭示植被变化、冬小麦压采、城市化等对山区和平原区ET的影响。结果表明, 1)研究时段内白洋淀流域ET和植被总初级生产力(GPP)及归一化植被指数(NDVI)均呈增加趋势,平均增长量为2.4 mm·a^(-1)、9.8 g·cm^(-2)·a^(-1)和0.0021·a^(-1)。2)降雨和植被恢复带来的GPP、NDVI增长是山区ET增加的主要因素, ET与GPP和NDVI的趋势变化在空间分布上具有很好的相似性,研究时段内山区ET增加56.5 mm。3)平原区ET受快速城市化、小麦种植面积压减和农田ET增加3个因素影响,虽然城市化和小麦压减都带来蒸散发减少,但仍无法抵消农田ET增加的效果,平原区ET总体增长了6.4 mm。就整个流域而言,减少山区植被和灌溉农田带来的ET增加对维持区域水资源可持续利用和绿色发展至关重要。

渭北旱地小麦新品种稳产性分析

陕西省渭南市是粮食生产大市,小麦种植面积和产量分别占全省30.1%和{34.8%},其中旱地小麦面积占到小麦总面积的1/3左右,产量占到1/4左右。旱地小麦丰欠直接关系全市夏粮丰产丰收。我们从省内外引进了旱地小麦新品种12个,采取多年多点试验的方法,以期筛选出适宜当地农业生产的优良旱地小麦品种。渭麦9号和晋麦47变异系数在不同年份均相当,表明渭麦9号和晋麦47是适合旱薄地种植的稳产品种。普冰9946在丰水年份的产量较高,丰产稳产性良好,适宜在丰水年份种植。

盐碱麦田生物有机肥促生增产培肥效果

【目的】研究不同生物有机肥对盐碱胁迫春小麦生长和土壤改良培肥的效果,为盐碱地的生物有机肥施用提供理论基础。【方法】采用盆栽试验,设置9个处理:不施肥处理(CK),4种不同菌种及配比的生物有机肥(A、B、C、D),每种生物有机肥设2个施量水平(1125,2250 kg/hm^(2))。【结果】与CK相比,施用生物有机肥后春小麦LAI、SPAD、理论产量、土壤有机质和速效养分含量等均显著增加(P<0.05),其中春小麦理论产量比CK处理增加了41.85%~74.93%,0~10 cm土层土壤有机质、碱解氮、速效磷和速效钾含量分别比CK提高了19.57%~66.24%、20.73%~40.12%、37.70%~75.72%和11.98%~31.12%,10~20 cm土层土壤有机质、碱解氮、速效磷和速效钾含量分别比CK提高了19.13%~74.63%、17.38%~29.93%、21.76%~59.52%和11.98%~31.12%,且随着生物有机肥施量的增加呈上升趋势;各施肥处理与不施肥CK相比显著降低了土壤pH和电导率(P<0.05),0~10 cm土层土壤pH、电导率分别比CK降低了2.55%~5.02%、10.33%~40.51%,10~20 cm土层土壤pH、电导率分别比CK降低了1.69%~4.20%、21.3%~43.60%。各施肥处理春小麦根际土壤细菌和放线菌数量显著高于CK(P<0.05),真菌数量显著低于CK(P<0.05),根际土壤细菌和放线菌数量随生物有机肥施量的增加呈上升趋势,真菌数量呈现下降趋势。【结论】D生物有机肥(沼泽红假单胞菌∶肉桂褐链霉菌∶胶冻样芽孢杆菌∶枯草芽孢杆菌=1∶2∶2∶2)施用量为2250 kg/hm^(2)时,对盐碱土壤改良培肥和调节微生物数量结构作用效果较好,且促进了小麦生产量的提高。

临沂市冬小麦规范化播种技术

为进一步规范临沂市冬小麦播种技术,提升播种质量,打好小麦丰产基础,经过多年试验研究与生产实践,从科学选用良种、精细整地、规范化播种等方面总结出临沂市冬小麦播种关键技术,将耕、耙和镇压3个因素配套应用,培育冬前壮苗,为临沂市冬小麦节本增效、抗逆减灾和稳产高产提供技术支撑。

黄土高原旱地小麦多年定位施用化肥的产量效应分析

以已进行 1 8年的小麦长期肥料定位试验为背景 ,研究了长期施用化肥条件下小麦的增产效应及其对小麦吸收养分量的影响。结果表明 :单施氮肥对小麦有增产作用 ,可以提高小麦籽粒的含氮量 ;1 8年施用氮肥平均增产 1 0 80 5kg hm2 ,增产率达 85 2 %;单施磷肥无明显的增产作用 ,平均减产率为 3 2 %,但可提高小麦籽粒的含磷量 ;氮磷配施有明显的增产作用 ,N、P配施增产率达 1 4 0 6 %,在N、P配施基础上施用钾肥增产率仅为 2 8%,无明显的经济效益 ,从养分平衡角度应考虑N、P、K的配合施用。

黄土高原旱地长期施肥对小麦养分吸收和土壤肥力的影响

通过定位试验研究了长期施肥对小麦子粒、秸杆养分吸收和土壤肥力变化的影响。结果表明,合理施用化肥不但增产幅度大,还在一定程度上增加了小麦N、P、K养分浓度。单施氮、单施磷肥能增加小麦子粒和秸杆的N、P、K吸收量,氮磷肥配施增加效果显著,其子粒吸收N、P、K增加了153.2%、157.1%和162.4%。施有机肥能补充土壤中的N、P、K含量,增加小麦子粒中的养分含量,使品质有大幅度的提高。单施磷肥的土壤有机质、全P、速效P含量增加,土壤全N、速效N含量减少,N素亏缺。氮磷肥配施加剧了土壤K的亏缺。有机肥培肥作用显著,有机肥和氮、磷肥配施的土壤有机质、全N、全P、速效N、速效P和速效K分别增加了69.0%5、7.5%、54.8%、73.1%、830.5%和119.1%。