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.

Identification of Rhizobia Isolated from Nodules of Mexican Commercial Soybean Varieties

Rhizobia, crucial for nitrogen fixation in leguminous plants, play a vital role in soybean cultivation. This study, conducted in Mexico, a major soybean importer, aimed to identify bacteria from nodules of five soybean varieties in high-production regions. Multilocus sequence analysis (MLSA) was employed for enhanced species resolution. The study identified six Bradyrhizobium species: Bradyrhizobium japonicum USDA 110, Bradyrhizobium japonicum USDA 6, Bradyrhizobium elkanii USDA 76, Bradyrhizobium neotropicale, Bradyrhizobium lablabi, and Bradyrhizobium icense. Bradyrhizobium japonicum USDA 110 predominated in the soils, displaying symbiotic preference for the Huasteca 400 variety. However, phylogenetic analysis didn't reveal a clear association between strains, soil, and soybean variety. This research sheds light on the diversity of rhizobia in Mexican soybean cultivation, contributing to the understanding of symbiotic relationships in soybean production systems.

Corn and Soybean Growth as Affected by Wastewater-Derived Struvite-Phosphorus Sources and Irrigation Water Types

Struvite (MgNH4PO4·6H2O) produced synthetically from a stock solution of known phosphorus (P) and nitrogen (N) concentrations has been shown to be an effective, alternative fertilizer-P source for various crops, but little is known about the potential agronomic effectiveness of struvite created from an actual municipal wastewater source. The objective of this study was to evaluate the effects of soil [i.e., Creldon silt loam (Oxyaquic Fragiudalf) and Calloway silt loam (Aquic Fraglossudalf) series], fertilizer-P source [i.e., synthetically produced electrochemically precipitated struvite (ECSTsyn), real-wastewater-derived ECST (ECSTreal), chemically precipitated struvite (CPST), monoammonium phosphate (MAP), and an unamended control (UC)], and irrigation water type (i.e., tapwater and struvite-removed wastewater) on corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] growth and N, P, and magnesium (Mg) uptake in a 60-day, greenhouse potted-plant study. Crop growth and N, P, and Mg uptakes for the struvite treatments (i.e., CPST, ECSTsyn, and ECSTreal) were generally similar to or at least 1.2 times greater than MAP. The ECSTsyn material commonly had up to five times greater N, P, and Mg uptake in corn and soybean than any other fertilizer-P source. Struvite-removed wastewater resulted in at least 1.3 times lower dry matter and N, P, and Mg uptake than tapwater. Similar corn and soybean results from the struvite fertilizers among the various soil-water type combinations compared to MAP suggest that struvite generates similar crop responses as at least one widely used, commercially available, multi-nutrient fertilizer-P source.

Effect of Biochar Type and Bradyrhizobium japonicum Seed Inoculation on Soybean Growth, Nodulation and Yield in a Tropical Ferric Acrisol

In tropical environments, most soybean growth studies have utilized rice husk biochar (RHB) in soil, even though it is low in nitrogen, potassium, and phosphorous. This may not give short-term agronomic performance relative to enriched biochar. Moreover, the impact of inoculating soybean seeds with atmospheric nitrogen-fixing bacterium Bradyrhizobium japonicum on nodulation and grain yield has produced inconclusive findings in the literature. This research therefore aims to assess the effect of poultry manure (PM), poultry manure biochar (PMB) and RHB alone and in combinations on grain yield, dry shoot and root biomass of soybeans in the semi-deciduous agro-ecological zone. In addition, the effect of B. japonicum inoculated and non-inoculated soybean seeds on nodulation and grain yield was also investigated. The treatments followed a split plot design studying inoculation and non-inoculation, soil amendments (eight), and control subplot factors, respectively. The results show that the amendment of a ferric acrisol with 4 Mg∙ha−1 PM, 10 Mg∙ha−1 RHB + 2 Mg∙ha−1 PM, and 5 Mg∙ha−1 RHB + 4 Mg∙ha−1 PMB with B. japonicum inoculated seed produced significantly greater grain yield (p = 0.05). PM treatment had a significant (p B. japonicum-inoculated soybean seeds significantly (p = 0.014) increased soybean nodulation. This study suggests that RHB combined with PM or PMB provides a beneficial source of N, P, and K, resulting in improved soybean yield and nodulation in a tropical ferric acrisol.

Assessing the Influence of Phosphorus Fertilization on the Growth and Yield of Maize/Soybean Intercrop by Analyzing Nitrogen Uptake

Intercropping, particularly the combination of maize and soybeans, has been widely recognized for its potential to improve nitrogen uptake and promote sustainable agriculture. This study examines the patterns of nitrogen uptake in maize and soybean intercropping systems under different growth stages and phosphorus fertilization levels and investigates the influence of nitrogen uptake on growth parameters such as plant height, leaf area, and biomass accumulation in the maize/soybean intercrop under different phosphorus fertilization regimes. The study also collected chlorophyll samples at different growth stages of maize in monoculture and intercropping with maize or soybean. The results showed that plant height was greater in V10 in both fertilized and unfertilized treatments for intercropped maize and soybean, and chlorophyll concentration was higher in VT intercropped maize. The results also showed a higher accumulation of biomass. Understanding the growth dynamics of these plants in monoculture and intercropping systems and the impact of fertilization practices is crucial for optimizing crop productivity and sustainability in agricultural systems.

Assessment of Nitrogen Fixation, Uptake, and Leaching in Maize/Soybean Intercropping System at Varied Soil Depths and under Phosphorus Application in Chinese Agricultural Settings

The study of Nitrogen fixation, uptake, and leaching at different soil depths in the co-cultivation of maize and soybean under phosphorus fertilization is important for sustainable agriculture. This study was conducted in Quzhou, Hebei Province, China, with MC812 maize and Jidou12 soybean varieties. Soil samples were taken from each plot to create a composite sample. The results show that nitrogen concentration varies at different depths and is higher in all treatments between 40 and 100 cm. Incorporating intercropping of maize and soybeans into farming practices can lead to more sustainable and environmentally friendly agriculture in China.

密植对不同年代大豆品种群体光合生产和产量形成的影响

密植是挖掘优良大豆品种生产潜力的有效途径,但对于育种时间跨度长达百年的大豆品种而言,其对密植的响应差异仍不清楚。为明晰密植对不同年代大豆品种群体光合生产和产量形成的影响,以1930s-2020s育成的50个大豆品种为试验材料,探究了不同年代大豆品种(1930s-1940s、1950s-1960s、1970s-1980s、1990s-2000s和2010s-2020s)在不同密度水平(常规密度200,000株hm^(–2)和高密度300,000株hm^(–2))下叶面积指数(LAI)、叶面积指数增长率(LGR)、光合势(LAD)、干物质积累、作物生长率(CGR)、下部叶片衰老和产量的响应差异。结果表明,随着育成年代的推进,大豆群体光合生产能力和产量均逐渐提升。与老品种(1930s-1940s,1950s-1960s和1970s-1980s)相比,新品种(1990s-2000s和2010s-2020s)在高密度下表现出更好的生长状态。新品种在高密度下的叶面积指数(LAI)增幅更大,盛荚期(R4)的LAI的增幅依次为17.79%和23.06%,盛荚-鼓粒期(R4-R6)的LAI衰减更缓慢,LAD增幅更大。在R6期,新品种在高密度下的干物质积累增幅更大,依次为25.28%和28.96%,其CGR也显著增加(P <0.05),依次为21.66%和25.38%;此外,新品种在高密度下下部叶片黄叶节位上移量和叶片SPAD值的降幅较小,表现出较强的抗衰老特性。在产量方面,新品种在高密度下单位面积粒数和荚数增幅较大,百粒重降幅较小,产量显著(P <0.05)提升,其产量增幅依次为4.49%和5.04%。综上,生育初期,新品种在高密度下表现出较强的“源”增加能力,其叶源值高且稳定,光能截获量大,干物质积累多,促进籽粒“库”快速发育;而生育后期,其叶面积指数衰减速度较慢,群体光合能力强,籽粒灌浆充分,因而显著提高单位面积粒数和荚数,从而弥补百粒重的微降,实现大豆产量显著提升。

Resistance Analysis of the Binary Insect-resistant Transgenic Soybean to Heliothis viriplaca

[Objective] The aim of the research was to analyze the resistance of binary insect-resistant transgenic soybean to Heliothis viriplaca.[Method]In this experiment, resistance analysis of the stabilized binary insect-resistant transgenic soybean to Heliothis viriplaca was conducted in lab and in field conditions.[Result] The results indicated that the leaves of insect-resistant transgenic soybeans T5-150 and T5-195 showed lighter damage than those of non-transgenic soybeans. Meanwhile, the Heliothis viriplaca larvae fed on leaves of these two transgenic soybeans were characterized by less leaf consumption, shortening survival day, slower development and less pupation.[Conclusion]It was concluded that insect-resistance of transgenic soybean to Heliothis viriplaca was increased dramatically and the research provided a reference for selecting binary insect-resistant transgenic soybean to Heliothis viriplaca.

鸡肉和黄豆混合发酵过程中蛋白质、氨基酸与风味变化规律

以纯黄豆发酵为对照,分析了鸡肉与黄豆混合发酵过程中蛋白质、氨基酸态氮、蛋白酶活力、游离氨基酸和挥发性风味物质的变化规律。结果表明,发酵过程中,样品的蛋白质含量呈下降趋势,氨基酸态氮、蛋白酶活力和游离氨基酸含量则呈上升趋势。不同发酵时期,鸡肉和黄豆混合发酵组中鲜味氨基酸和总游离氨基酸含量均显著高于纯黄豆发酵(P<0.05),挥发性风味物质的积累也较纯黄豆发酵多。通过正交偏最小二乘判别分析(orthogonal partial least squares discriminant analysis,OPLS-DA)结合气味活性值(odor activity value,OAV)进一步分析得出,3-甲硫基丙醛、苯甲醛、苯乙醛和1-辛烯-3-醇是鸡肉与黄豆混合发酵过程中的关键差异挥发性风味物质。该研究结果为高品质豆基发酵调味品的开发和品质调控提供了理论参考。

Analyses of Protein and Oil of Maize Offsprings Plants Introducing Soybean DNA

[Objective] The experiment was aimed to explore character variation between different families after DNA introduction and select variant plants with good stability. [Method] The method of pollen-tube-pathway was used to introduce total DNA of soybean into normal maize inbred line 7313 for selecting generation by generation. When field characters of maize, grain colors, grain traits and panicle axis colors were stable, the crude protein, gliadin, glutelin and oil content of grains which were selected from variant strains were detected and compared. [Result] The grain crude protein, gliadin, glutelin and oil content of line 26h-4-3 were significantly different from these of control treatment. The increments of D3 and D4 generation were 10.34% and 26.70%, 6.58% and 6.28%, 15.09% and 70.34%, 55.82% and 51.52% respectively. All indexes of line 26h-3-1 were also higher than these of control treatment and the increments of D3 and D4 generation were 5.67% and 21.63%,1.91% and 2.31%, 10.85% and 62.27%,22.49% and 9.67%. [Conclusion] The crude protein, gliadin, glutelin and oil content of variant line 26h-4-3 and 26h-3-1 were stable, so variant line 26h-4-3 and 26h-3-1 were excellent variant strains which satisfied the requirement of high protein breeding.

Identification of Endophytic Bacillus BHL3501 from Wild Soybean and Its Inhibitory Effect against Soybean Cyst Nematode (Heterodera glycines Ichinohe)

[ Objective] The paper was to identify endophytic bacillus BHL3501 from wild soybean and its inhibitory effect against soybean cyst nematode. [ Meth- od] Through morphological characteristic, physiological and biochemical characteristics and 16S rDNA analysis, a strain of endophytic bacterium BHL3501 with ne- maticidal activity isolated and screened from the root of wild soybean was identified, the effects of BHL3501 metabolite solutions with different dilution multiples on egg hatching and activity of 2rd instar juvenile of soybean cyst nematode were also studied. [ Result ] BHL3501 strain was preliminarily identified to be Bacillus sp.. The relative inhibitory rate of its original fermentation broth on egg hatching of soybean cyst nematode after 24 h was 98.3% ; the relative inhibitory rate under 10- time diluted solution treatment was 79.5%, which had significant difference with sterile water control. The corrected mortality rate of 24 instar juvenile was 93.1% after treated by original fermentation broth for 24 h, the treatments of all diluted solutions had significant difference with sterile water control. [ Conclusion ] BHL3501 metabolites had strong inhibitory effect against egg hatching of soybean cyst nematode, which also had strong toxic effect on its 2nd instar juvenile.

菜用大豆(Soybean)引种试验研究

[目的]筛选适宜大规模栽培的大豆优良株系。[方法]对引进的5个菜用大豆株系在种植生态条件下的植物学特征,农艺性状等进行评价及筛选。[结果]结果表明,通过比较分析,4号株系表现的生育期短,干耔产量较低,结荚个数较少;可利用的鲜粒,鲜荚较大,籽粒饱满,秕荚率低;矮株抗倒伏,6月份收获鲜荚。[结论]大豆可考虑引进栽培。

玉米大豆间作对喀斯特区土壤理化性质及微生物碳代谢特征的影响

为探明喀斯特区玉米大豆带状复合种植对土壤理化性质及微生物群落结构多样性的影响,本研究设置玉米大豆间作(MSI)、玉米单作(MM)和大豆单作(SM) 3种模式,采用Biolog-ECO微孔培养法,旨在揭示玉米大豆种植模式对土壤微生物碳源代谢活性、多样性以及土壤性质的影响及其机制。结果表明,与MM及SM相比, MSI土壤微生物群落丰富度指数(McIntoshindex)分别显著提高了11.90%和58.40%,平均颜色变化率(averagewellcolordevelopment, AWCD)分别显著增加了24.50%和80.10%,羧酸类、氨基酸类和酚酸类碳源的平均相对吸光度分别显著提高了34.50%、63.70%和61.80%;碳源代谢指纹图谱表明,MSI模式中土壤微生物通过提高衣康酸的代谢活性进而增加了对羧酸类碳源的利用,通过提高L-苯丙氨酸、L-苏氨酸和甘氨酰-L-谷氨酸的代谢活性从而增加了氨基酸类碳源利用,通过提高吐温40、吐温80和肝糖的代谢活性从而增加了对多聚类碳源的利用;同时, MSI处理土壤SOC分别较MM和SM显著提高8.50%和72.84%, NH_4~+-N和TN含量分别较SM处理显著增加46.70%和33.30%;主成分分析表明,提取的2个主成分解释了碳源利用总变异的79.69%,种植模式对碳源代谢的综合利用能力表现为MSI>MM>SM,其中MSI土壤微生物群落对羧酸类、氨基酸类和多聚类代谢利用能力最强;冗余分析则表明,显著影响碳源代谢利用的2个环境因子分别是TN (53.50%)和SOC (30.90%),其中TN促进了羧酸类和氨基酸类碳源的代谢利用, SOC加强了胺类和酚酸类碳源的利用。综上可见,玉米大豆间作模式土壤微生物碳代谢的偏好性主要由微生物群落结构多样性引起,同时又受土壤全氮和有机质含量的调控,表明微生物群落结构与土壤理化因子间的互作可能是大豆玉米复合种植增产增效的一个关键因素。

春大豆合理播期确定动态知识模型构建

为提高春大豆播种期确定的时效性和准确性,利用农田信息采集系统获取土壤墒情及环境信息,并根据大豆播种进程与适宜环境、土壤墒情同步原理,采用隶属函数方法,将播种农艺要求与播种影响因素间的关系函数化,建立春大豆合理播期确定知识模型;并利用2个不同生态点的气象与土壤温湿度等参数,结合模型决策日期与2年中各地实际播期及出苗情况,对春大豆合理播期确定模型进行了实例验证。结果表明:2021年北15、2022年北14两块试验地播期确定模型输出结果与农田实际播期分别为4月23日、4月24日与5月7日、5月10日,月度误差分别为3.33%和9.68%,模型结果准确率分别为96.67%和90.32%。模型设计结果与当前高产春大豆实际农作制度体现较好的一致性和适用性,可以为农业生产者应用信息化手段确定春大豆播种期提供技术参考。

The Applied Research of Soybean Peptide in Feedstuffs

The soybean peptide has the trait of amino acid balance,digestible and easy to absorb,low allergy and low antigenicity.Furthermore,it also showed the feature of good mobility and thermal stability at high concentrations.This paper seeks to study the processing and nutritional characteristics of soybean peptide.And on that basis to lucubrate soybean peptide as a safe,efficient feedstuffs additives.The aim is to improve the feedstuffs quality.

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.

QTL Analysis of Major Agronomic Traits in Soybean

Soybean is a main crop, and most agronomic traits of soybean are quantitative; therefore, there is vely important studying and applying value to locating these traits. A F2：10 RIL population containing 154 lines, derived from the cross between Charleston as female and Dongnong 594 as male parent, were used in this experiment. A genetic linkage map was constructed with 164 SSR primers, which were screened with the two parents and amplified on the 154 lines. 12 agronomic traits different between the two parents were investigated, and QTLs of all the traits were analyzed using the software Windows QTL Cartographer V2.0. The agronomic traits included quality traits： protein content, oil content, and content of protein and oil; yield traits： pods per plant, seed weight per plant, and 100 seeds weight; and other agronomic traits： plant height, days to maturity, branches, nod number in main stem, average leaf length, and average leaf width. The results showed that 68 QTLs in total were found for the 12 agronomic traits. The number of QTLs per trait varied from 3 for the average leaf width to 11 for 100 seeds weight and plant height, and was 5.8 on average. Good accordance was seen in many QTLs between the results of this study and the results obtained by other similar studies; therefore, these QTLs may be valuable for molecular marker assistant selection in soybean. In this study, 68 major QTLs of 12 important traits of soybean were analyzed.

Feeding of Riptortus pedestris on soybean plants, the primary cause of soybean staygreen syndrome in the Huang-Huai-Hai river basin

Staygreen syndrome or Zhengqing in soybean has recently become a major issue for Chinese growers in the Huang-Huai-Hai river basin.Although previous studies revealed that staygreen can be induced when pods/seeds are damaged, it is unknown whether virus infection or insect infestation causes staygreen.To determine whether viral infection causes staygreen, a survey of soybean staygreen incidence in the Huang-Huai-Hai river basin was conducted in 2016 and 2017.Diseased samples were collected and analyzed using DAS-ELISA for Soybean mosaic virus, Watermelon mosaic virus, Bean pod mottle virus, Cucumber mosaic virus, and Bean common mosaic virus.The survey showed that the severity of soybean staygreen syndrome was most prevalent in Beijing, Henan, Shaanxi, and some parts of Shandong provinces, with yield losses from 0 to nearly 100%, but only a small fraction of samples were positive for the tested viruses.A field cage experiment and an insecticide treatment field trial were conducted to determine the contribution of the bean bug, Riptortus pedestris, to staygreen incidence.The field cage experiment showed that R.pedestris treatment resulted in shorter plants, more empty pods, increased numbers of abnormal seeds, and decreased yields.The field experiment showed that there were fewer R.pedestris and less soybean staygreen incidence in fields treated with insecticide than in untreated control fields.Together, these results suggest that R.pedestris infestation rather than virus infection induces staygreen syndrome and that growers in this region can mitigate staygreen syndrome via bean bug control.

Isolation of bacteria from fermented food and grass carp intestine and their efficiencies in improving nutrient value of soybean meal in solid state fermentation

Background: Soybean meal is an excellent and cost-effective protein source; however, its usage is limited in the piglet due to the presence of anti-nutritional factors and the antigens glycinin and β-conglycinin. The objective of the current study was to screen and select for bacteria that can be efficiently adopted to ferment soybean meal in order to solve this problem.Results: Bacteria were isolated from fermented soy foods and the grass carp intestine, and strains selected for high protease, cellulase and amylase activities. The isolated bacteria were characterized as Bacillus cereus, Bacillus subtilis and Bacilus amyloliquefacien, respectively. Fermentation with food-derived Isolate-2 and fish-derived F-9 increased crude protein content by 5.32% and 8.27%, respectively; improved the amino acid profile by increasing certain essential amino acids, broke down larger soy protein to 35 k Da and under, eliminated antigenicity against glycinin and β-conglycinin, and removed raffinose and stachyose in the soybean meal following a 24-h fermentation.Conclusions: Our results suggest these two B. amyloliquefaciens bacteria can efficiently solid state ferment soybean meal and ultimately produce a more utilizable food source for growing healthy piglets.

Physiological and molecular studies of staygreen caused by pod removal and seed injury in soybean

Leaves provide substances and signals for pod and seed development in soybean.However,the regulatory feedbacks of pod and seed to leaf development remain unclear.We investigated the effects of pod and seed on leaf senescence by conducting pod removal and seed injury experiments.Pod removal and seed injury delayed leaf senescence and caused the staygreen phenotype of leaves.There were dosage effects of pod number on the extent of staygreen in depodded plants.The concentrations of chlorophyll(SPAD value,an index of relative chlorophyll content),soluble protein,and soluble sugar in the leaves of depodded plants were higher than those of intact plants.During seed development,the content of IAA decreased,while that of ABA increased.This trend was more pronounced in intact than in depodded and seed-injured plants.The GA3/ABA ratio decreased gradually in all treatments.The content of GA3 was relatively stable and was higher in intact than in depodded plants.The expression levels of four senescence-related genes,Gm SARK,Gm SGR1,Gm CYN1,and Gm NAC,declined in depodded or seed-injured treatments and were positively correlated with the number of leaves retained on plants.Gm FT2 a,the major flowering-promoting gene,was expressed at a higher level while E1,a key flowering inhibitory gene,was expressed at a lower level in depodded than in intact plants.We propose that the pod or seed can regulate leaf development.When the seed is aborted owing to disease infection or pest attack,the leaves stay green because of the absence of the seed signals for senescence.