Soybean Intercropping Research Articles

Does a Soybean Intercrop Increase Nodule Number, N Uptake and Grain Yield of the Followed Main Crop Soybean?

It is not known whether seed inoculated soybean intercropping can increase the number of nodules, nitrogen uptake and yield of the subsequent main crop, soybean. For this reason, the soybean intercropping approach, sole or mixed cropping with buckwheat, was adopted to examine the influence of inoculation and intercropping of soybean and buckwheat on the subsequent main crop, soybean. Field trials were conducted from 2016 to 2019 in Germany and Poland. For this purpose, soils on which soybeans had not been grown in the past were selected as experimental plots and laid out in a split-plot design. It was surprising that even without inoculation a nodule growth could be documented. However, intercrop inoculation resulted in an average of 12 times more nodules per plant at four out of five sites. In addition, a 43% higher number of nodules was found on the lateral roots of the main soybean crop when intercropping with inoculated soybean occurred. The influence of the intercrop on the main crop soybean also depended on their growth in late summer and autumn. Further, there was a medium relationship (R = 0.7) between the number of nodules in the intercrop soybean and the nitrogen content of the soybean grain in the main crop. In terms of soybean grain yield, a single inoculation of the intermediate soybean crop contributed an average of 5% higher yield and inoculation of both the intercrops, and the main crop improved yield by 15%.

Shade-Tolerant Soybean Reduces Yield Loss by Regulating Its Canopy Structure and Stem Characteristics in the Maize-Soybean Strip Intercropping System.

The shading of maize is an important factor, which leads to lodging and yield loss of soybean in the maize–soybean strip intercropping system, especially in areas with low solar radiation. This study was designed to explore how shade-tolerant soybean reduces yield loss by regulating its canopy structure and stem characteristics in the maize–soybean strip intercropping system. The soybean cultivars Tianlong No.1 (TL-1, representative of shade-tolerant plants) and Chuandou-16 (CD-16, representative of shade-intolerant plants) were grown in monocropping and intercropping systems from 2020 to 2021 in Chongzhou, Sichuan, China. Regardless of shade-intolerant or shade-tolerant soybean, the canopy and stem of soybean in strip intercropping were weaker than those of the corresponding monoculture. But compared with shade-intolerant soybean, the shade-tolerant soybean slightly changed its spatial structure of canopy and stem morphology and physiology in maize–soybean strip intercropping system, especially in the later growth stages. On the one hand, the canopy of shade-tolerant soybean showed relatively high transmission coefficient (TC) and relatively low leaf area index (LAI) and mean leaf angle (MLA). On the other hand, the stem of shade-tolerant soybean was obviously stronger than that of shade-intolerant soybean in terms of external morphology, internal structure, and physiological characteristics. Additionally, compared with shade-intolerant soybean, shade-tolerant soybean showed higher APnWP (the average net photosynthetic rate of the whole plant) and seed yield in the strip intercropping. The results showed that shade-tolerant soybean increased light energy capture and photosynthesis in the different canopy levels to promote the morphological and physiological development of the stem and ultimately reduce the yield loss of the strip intercropping system. However, the molecular mechanism of low radiation regulating soybean canopy structure (LAI, TC, and MLA) needs further in-depth research to provide theoretical guidance for cultivating plants with ideal canopy shape that can adapt to changing light environment in intercropping system.

Photosynthetic and growth characteristics of apple and soybean in an intercropping system under different mulch and irrigation regimes in the Loess Plateau of China

The shortage of and intense competition for water and light are the main factors restricting the productivity of agroforestry systems in the Loess Plateau of western Shanxi, China. The combination of soil mulch and irrigation in agroforestry systems can regulate the interspecific relationships and increase the productivity of the component crops. However, the effects of mulch and irrigation regimes on the photosynthetic physiological characteristics of the agroforestry system and its synergistic mechanisms are still unclear. A 3-year experiment with two factors, mulch and irrigation, was conducted to investigate the effects of different mulch practices and irrigation levels on the photosynthetic characteristics, growth indices, and interspecific relationships of a fruit tree-crop intercropping system. An apple–soybean intercropping system was selected as the research object, and two mulch types [straw mulch (M1) and plastic mulch (M2)] and four maximum irrigation levels [no irrigation (W0), 55% (W1), 70% (W2), and 85% (W3) field capacity (Fc)] were tested. No mulch together with no irrigation was the control treatment (CK). The results showed that there was no photosynthetic siesta phenomenon in the intercropping system, and the daily variations of the net photosynthetic rate (Pn) and transpiration rate (Tr) were unimodal. The mean values for Pn, Tr, and leaf photosynthetic efficiency (PUE) of the apple and soybean under the M2 treatment were generally higher than under the M1 treatment, whereas Tr and PUE increased as the amount of irrigation increased. In 2017–2018, the maximum mean Pn values for both apple and soybean were observed under the M2W2 treatment, whereas in 2019, they were observed under the M2W3 treatment. The Pn, Tr, and leaf intrinsic water use efficiency (WUEi) of soybean correlated positively with the distance from the trees, whereas PUE correlated negatively with it. Mulch and water replenishment increased apple shoot growth and the height, leaf area index, and yield of soybean, especially under plastic mulch. A principal components analysis found that the M2W2 treatment had the highest comprehensive benefits in 2017–2018, whereas in 2019, the highest were achieved with the M2W3 treatment. Therefore, to optimize the photosynthetic efficiency and yield of the apple–soybean intercropping system in the loess region of western Shanxi, we suggest a combination of plastic mulch and maximum irrigation of 70% Fc in normal years, but maximum irrigation should be increased to 85% Fc in dry years.

Effects of Different Intercropping Models on Growth and Yield Traits of Maize in Red Soil Dryland

In order to develop the suitable planting mode of maize in red soil dryland, improve the related plant and ear characters of maize, promote high quality and high yield, and improve economic benefits. The experiment was conducted in the Science and Technology Park of Jiangxi Agricultural University from May 13, 2020 to October 18, 2020 and from May 5, 2021 to October 7, 2021. Taking maize as the control, three intercropping treatments of maize intercropping soybean, maize intercropping peanut and maize intercropping sweet potato were set up to compare their effects on agronomic characters such as plant height, stem diameter and ear width of maize and yield. The results showed that the plant height and ear height of maize intercropping soybean reached the maximum in two years, with plant height of 208.9 cm and 191.9 cm, ear height of 80.2 cm and 58.4 cm, respectively. The ear length and grain number per row of intercropping treatment were better than that of monoculture treatment. The ear length of maize intercropping and soybean reached the maximum, which were 16.5 cm and 19.0 cm respectively, and the grain number per row was also higher than that of other treatments. The yield of maize intercropping soybean was the highest, 42.1 kg and 43.5 kg respectively in two years. Compared with monoculture, intercropping can improve stem diameter, ear height, ear length, grain number per row and other ear traits, so as to improve corn yield, among which maize intercropping soybean is the best. The results of grey correlation showed that ear length and plant height had a great influence on maize yield. The comprehensive analysis shows that the use of maize intercropping soybean model is conducive to achieve high quality and high yield.

Comparative Effects of Mineral Fertilizer and Two Poultry Manures on the Growth and Yield of Maize/Soybean Intercrop

Maize/soybean intercrop was established in the experimental farm of NCRI Badeggi. The design of the experiment was RCBD, with eight treatments and three replicates. The experiment was designed to investigate the comparative effects of mineral fertilizer, and two poultry manures on the growth parameters and yield of maize /soybean intercrop. The study evaluated the effects of broiler and local chicken manure applied each at the rates of 2 t/h, 4t/h and 6t/h with or without mineral fertilizer. NPK fertilizer at the rates of 40 kg/ha and 20kg/ha combined with poultry manures at the rates of 2 t/h and 4t/h respectively, while poultry manure at 6 t/h and NPK at 60 kg/ha were applied as sole treatments. There was a control treatment with neither poultry manure nor mineral fertilizer. Data were separately collected on the vegetative and yield parameters of both maize and soybeans. Agronomic activities such as weeding, thinning and applications of insecticides were appropriately carried out. Local chicken manure integrated with an ample quantity of NPK fertilizer enhanced the growth and yield parameters of both maize and soybean in maize soybean intercrop. Results obtained from this experiment indicated that local chicken manure at the rate of 2 t/ha and 4 t/ha integrated with NPK fertilizer, at the rate of 40kg/ha and 20kg/ha respectively, significantly influenced the number of cob per plot, cob weight per plot, grain weight per plot, days to 50% silking, as well as days to maturity in maize. Sole local chicken manure applied at the rate of 6 t/ha significantly enhanced plant vigour in soybean, three weeks after planting. The yield performance of maize crops treated with Local chicken manure surpassed those of sole broiler manure and sole NPK fertilizer. Results from this work also demonstrated the efficiency of poultry manure when integrated with commercial fertilizer.

SUSTAINABLE AGRICULTURAL PLANNING IN ORDER TO SUPPORT FOOD SECURITY (FOOD ESTATE) IN THE TIMANG GAJAH SUB-WATERSHED, BENER MERIAH REGENCY

Good watershed management is the rational use of natural resources in the watershed to obtain maximum production in unlimited time, minimize the danger of damage (land degradation), and obtain an even water yield throughout the year. Timang Gajah sub-watershed with an area of 35,859.26 ha is one of the sub-watersheds of the Krueng Peusangan watershed. According to the results of research by Akbar et al. (2020), the Timang Gajah sub-watershed is included in the sub-watershed that needs to be restored. Judging from the critical land area, the Timang Gajah sub-watershed consists of very critical 2,398.47 ha, critical 23,989.87 ha, moderately critical 6,402.59 ha, potentially critical 3,063.97 ha and not essential 4.36 ha (BPDASHL, 2020). This shows that the Timang Gajah sub-watershed needs serious handling in its management. The purpose of this study is to develop a plan for sustainable use of agricultural land in the Timing Gajah sub-watershed that can reduce the rate of erosion (erosion < ETol) a decent income for each farmer (income > KHL). The cropping pattern planned in this study is a cropping pattern that supports food security (Food Estate). The research method that will be used in this research is a survey method which consists: 1) the preparation stage, 2) the preliminary survey stage, 3) the main survey stage and 4) the data analysis stage and the presentation of the results. The results showed that the predictive value of erosion obtained on mixed garden land use (SPL 2, 5, 12, 13 and 18) ranged from 18.70 - 103.81 tons/ha/year, while the ETol value ranged from 14.97 - 33.27 tons/ha/year. The predictive value of erosion on plantation land use (SPL 15) is 56.36 tons/ha/year, and the ETol value is 28.42 tons/ha/year. Meanwhile, the predicted erosion value for scrubland use (SPL 8, 9, 10, 11, 16 and 17) ranged from 23.81 - 73.67 tons/ha/year and ETol values 14.01 - 27.72 tons/year. Ha/year. The recommended intercropping pattern at the research location, especially in mixed garden land use, is potato and corn (A1) plus other businesses (livestock), potato and soybean (A2) intercropping, potato and peanut intercropping. Green (A3), intercropping of potato with chilli (A4) and monoculture potato plus other livestock business (A5) generate net income above decent living income for local farmers (Rp 66.400.000 / household/year).

Dynamic changes of rhizosphere soil bacterial community and nutrients in cadmium polluted soils with soybean-corn intercropping

BackgroundSoybean-corn intercropping is widely practised by farmers in Southwest China. Although rhizosphere microorganisms are important in nutrient cycling processes, the differences in rhizosphere microbial communities between intercropped soybean and corn and their monoculture are poorly known. Additionally, the effects of cadmium (Cd) pollution on these differences have not been examined. Therefore, a field experiment was conducted in Cd-polluted soil to determine the effects of monocultures and soybean–corn intercropping systems on Cd concentrations in plants, on rhizosphere bacterial communities, soil nutrients and Cd availability. Plants and soils were examined five times in the growing season, and Illumina sequencing of 16S rRNA genes was used to analyze the rhizosphere bacterial communities.ResultsIntercropping did not alter Cd concentrations in corn and soybean, but changed soil available Cd (ACd) concentrations and caused different effects in the rhizosphere soils of the two crop species. However, there was little difference in bacterial community diversity for the same crop species under the two planting modes. Proteobacteria, Chloroflexi, Acidobacteria, Actinobacteria and Firmicutes were the dominant phyla in the soybean and corn rhizospheres. In ecological networks of bacterial communities, intercropping soybean (IS) had more module hubs and connectors, whereas intercropped corn (IC) had fewer module hubs and connectors than those of corresponding monoculture crops. Soil organic matter (SOM) was the key factor affecting soybean rhizosphere bacterial communities, whereas available nutrients (N, P, K) were the key factors affecting those in corn rhizosphere. During the cropping season, the concentration of soil available phosphorus (AP) in the intercropped soybean–corn was significantly higher than that in corresponding monocultures. In addition, the soil available potassium (AK) concentration was higher in intercropped soybean than that in monocropped soybean.ConclusionsIntercropped soybean–corn lead to an increase in the AP concentration during the growing season, and although crop absorption of Cd was not affected in the Cd-contaminated soil, soil ACd concentration was affected. Intercropped soybean–corn also affected the soil physicochemical properties and rhizosphere bacterial community structure. Thus, intercropped soybean–corn was a key factor in determining changes in microbial community composition and networks. These results provide a basic ecological framework for soil microbial function in Cd-contaminated soil.

Photosynthesis and Fine Root Growth Dynamics of Soybean in Walnut-Soybean Agroforestry System.

Agroforestry system is regarded as a promising practice in sustainable agricultural management. However, the effects of long-term tree-based intercropping on crop remain poorly understood, especially in the Loess Plateau (China). In this study, the impacts of photosynthetic and respiration rate were determined by the portable photosynthesis system (Li-6400), and the effects of the root growth dynamics of soybean in the walnut-soybean intercropping system were measured by soil auger and WinRHIZO root analysis system, in the Loess Plateau. The results showed that soybean reached the highest net photosynthetic rate during flowering period, with the net photosynthetic rate of intercropped soybean, which was 20.40 μmol·m−2·s−1, significantly higher than that of its monocropped counterpart. Soybean biomass reached the maximum during the pod-bearing period, with intercropped soybean biomass being 25.49 g, significantly higher than that of its monocropped counterpart. The mean diameter and increased density of soybean fine roots reduced along with increased soil depth. Both the diameter (0.43 mm) and increased density (930 cm/dm3) of intercropped soybean fine roots were evidently higher than those of monocropped soybean (0.35 mm, 780 cm/dm3). With increasing cropping years, fine roots of intercropped soybean tended to be mainly distributed in soil at a depth between 0 and 20 cm from the fifth year. Collectively, compared with soybean monoculture, walnut-soybean agroforestry system is more conducive to soybean growth in the Loess Plateau.

Increased nodular P level induced by intercropping stimulated nodulation in soybean under phosphorus deficiency

Low P availability is a vital constraint for nodulation and efficient N2 fixation of legume, including soybean. To elucidate the mechanisms involved in nodule adaption to low P availability under legume/cereal intercropping systems, two experiments consisting of three cropping patterns (monocropped soybean, monocropped maize, soybean/maize intercropping) were studied under both sufficient- and deficient-P levels. Our results demonstrated that intercropped soybean with maize showed a higher nodulation and N2 fixation efficiency under low P availability than monocropped soybean as evidenced by improvement in the number, dry weight and nitrogenase activity of nodules. These differences might be attributed to increase in P level in intercropping-induced nodules under low P supply, which was caused by the elevated activities of phytase and acid phosphatases in intercropping-induced nodules. Additionally, the enhanced expression of phytase gene in nodules supplied with deficient P level coincided with an increase in phytase and acid phosphatase activities. Our results revealed a mechanism for how intercropped maize stimulated nodulation and N2 fixation of soybean under P deficient environments, where enhanced synthesis of phytase and acid phosphatases in intercropping-induced nodules, and stimulated nodulation and N2 fixation.

Diversity of Natural Enemies in Corn - Soybean Intercropping with Different Plant Compositions

Intercropping is one of the polyculture crop cultivation techniques. Polyculture cropping system can increase the diversity of insects. This research aims to determine the effect of different plant composition of soybean and corn on the diversity and abundance of natural enemies. This research was carried out using a single factor experimental method arranged in a single plot field design. The treatment tested was the plant composition of soybean and corn which consisted of 4 compositions setting as treatment i.e., 2:1, 3:1. 4:1 and 5:1. In addition, monoculture soybeans and monoculture corn were also planted for comparison. Observation and sampling of natural enemies were carried out using insect sweeping net, yellow pan trap, and pitfall trap. Samplings were done 7 times when the plant at 2, 3, 4, 6, 8, 10, and 12 weeks old. The results showed that the plant composition of soybean and corn affected the number of species and abundance of insect natural enemies. Nonmetric multidimensional scale analysis shows that there are less differences in the composition of insect natural enemies between different plant compositions.

Physio-morphological of Soybean in Monoculture and Intercopping with Corn

Soybean is the main food crop in Indonesia after rice and corn. Soybean is a raw material for several foods which are a good source of fiber for the human body. Soybean productivity in Indonesia is still low at 15.24 Ku/Ha because farmers are still using a monoculture cropping system, which causes plant physiological processes to be not optimal so that growth and yields are low. One of the efforts to increase soybean growth and yield is by the intercropping system. The potential crop for intercropping with soybeans is corn because it has different physiological and morphological characteristics. This study explained the physiological aspects of plant height and number of leaves, leaf area, plant dry weight, and yield. The treatment tested were monoculture soybean and soybean intercropping with various proportions of corn population. The result showed that soybean and corn intercropping produced higher physio-morphology than monoculture soybeans.

The effect of strip orientation and width on radiation interception in maize–soybean strip intercropping systems

AbstractMaize–soybean intercropping systems are widely used in developing countries, but few studies have been performed to optimize such systems. The effects of strip width and orientation on photosynthetically active radiation (PAR) distribution characteristics were therefore determined to gain a better understanding of crop productivity in maize–soybean intercropping systems. A series of intercropping experiments incorporating different strip orientations and widths were conducted. In addition, an improved radiation transmission model was used to simulate PAR interception by the maize and soybean crops. We found that more PAR was intercepted by the soybean plants than by the maize plants when the strip orientation angle increased from 0° to 90° in the maize–soybean intercropping systems. This result was obtained in most of the main maize production areas, including those with different latitudes. The effect of strip widths within the intercropping systems also had a significant effect on PAR interception. The relative fraction of PAR intercepted ranged from 39.4% to 86% for soybean and 105.8% to 169.3% for maize. The effect of soybean strip width on leaf PAR interception was greater than that of maize strip width. These results are not only of fundamental biological importance but they also have important implications for agriculture in terms of the optimization of production in intercropping systems.

Diethyl Aminoethyl Hexanoate Increase Relay Strip Intercropping Soybean Grain by Optimizing Photosynthesis Aera and Delaying Leaf Senescence.

Insufficient and unbalanced biomass supply inhibited soybean [Glycine max (L.) Merr.] yield formation in the maize-soybean relay strip intercropping (IS) and monoculture soybean (SS). A field experiment was conducted to explore the soybean yield increase mechanism of DA-6 in IS and SS treatments. In this 2-year experiment, compact maize “Denghai 605” and shade-tolerant soybean “Nandou 25” were selected as cultivated materials. DA-6 with four concentrations, i.e., 0 mg/L (CK), 40 mg/L (D40), 60 mg/L (D60), and 80 mg/L (D80), were sprayed on soybean leaves at the beginning of flowering stage of soybean. Results showed that DA-6 treatments significantly (p < 0.05) increased soybean grain yield, and the yield increase ratio was higher in IS than SS. The leaf area index values and net photosynthesis rate of IS peaked at D60 and were increased by 32.2–49.3% and 24.1–27.2% compared with the corresponding CK. Similarly, DA-6 treatments increased the aboveground dry matter and the amount of soybean dry matter accumulation from the R1 stage to the R8 stage (VDMT) and highest at D60 both in IS and SS. D60 increased the VDMT by 29.0–47.1% in IS and 20.7–29.2% in SS. The TRG at D60 ranged 72.4–77.6% in IS and 61.4–62.5% in SS. The MDA content at D60 treatment was decreased by 38.3% in IS and 25.8% in SS. The active grain-filling day in IS was about 7 days longer than in SS. In D60 treatment, the Vmean and Vmax increased by 6.5% and 6.5% in IS and 5.7% and 4.3% in SS compared with the corresponding CK. Although the pod number and hundred-grain weight were significantly (p < 0.05) increased by DA-6 treatments, the grains per pod were maintained stable. The pod number and hundred-grain weight were increased by 30.1–36.8% and 4.5–6.7% in IS and 6.3–13% and 3.6–5.6% in SS. Thus, the grain yield at D60 was increased by 36.7–38.4% in IS and 21.7–26.6% in SS. DA-6 treatments significantly (p < 0.05) increased soybean grain yield and peaked D60 treatments both in IS and SS.

Simulation of the Growth and Leaf Dynamic in Quality Protein Maize and Soybean Intercropping Under the Southwestern Savannah Conditions of DR Congo

Simulation of the Growth and Leaf Dynamic in Quality Protein Maize and Soybean Intercropping Under the Southwestern Savannah Conditions of DR Congo

Growth, photosynthesis and yield of soybean in ridge-furrow intercropping system of soybean and flax

It is of practical significance to control the excessive vegetative growth of soybean during the rainy season, which causes a reduction in yield. In this study, we adopted soybean flax ridge-furrow intercropping system in order to constrain soybean’s excessive vegetative growth by interspecific competition between intercrops and estimated the growth, photosynthesis and yield of soybean. Two-year-experiment was conducted in 2018 and 2019 in the experimental farm of KIM IL SUNG University. Soybean seeds were grown in ridges and flax seeds were in furrows between ridges. During the co-growth stage, the early growth of soybean intercropped with flax was depressed by interspecific competition. At 45 days after soybean sowing, just before flax harvest, the average height and stem diameter of intercropped soybean plant were 22.5 cm and 0.7 mm shorter than those of sole cropped soybean plant, respectively. At the reproductive growth stage, the height of intercropped soybean plant was still 18.5 cm shorter than sole cropped soybean, while other agronomic parameters, including leaf area index (LAI), dry matter per plant, photosynthetic rate and chlorophyll contents, were greater for intercropped soybean. This led to higher yield of soybean (118.5%) and land equivalent ratio (LER) (203.5%) in ridge-furrow intercropping, as compared to sole cropping. Our results suggest that ridge-furrow intercropping system can be an effective way to constrain soybean’s excessive vegetative growth during the rainy season and improve soybean seed yield and LER.

Genetically Modified Sugarcane Intercropping Soybean Impact on Rhizosphere Bacterial Communities and Co-occurrence Patterns.

Strategies involving genes in the dehydration-responsive element binding (DREB) family, which participates in drought stress regulation, and intercropping with legumes are becoming prominent options in promoting sustainable sugarcane cultivation. An increasing number of studies focusing on root interactions in intercropping systems, particularly involving transgenic crops, are being conducted to better understand and thus, harness beneficial soil microbes to enhance plant growth. We designed experiments to investigate the characteristics of two intercropping patterns, soybean with wild-type (WT) sugarcane and soybean with genetically modified (GM) Ea-DREB2B-overexpressing sugarcane, to assess the response of the rhizosphere microbiota to the different cropping patterns. Bacterial diversity in the rhizosphere microbial community differed between the two intercropping pattens. In addition, the biomass of GM sugarcane that intercropped with soybean was significantly improved compared with WT sugarcane, and the aboveground biomass and root biomass of GM soybean intercropping sugarcane increased by 49.15 and 46.03% compared with monoculture. Furthermore, a beneficial rhizosphere environment for the growth of Actinobacteria was established in the systems intercropped with GM sugarcane. Improving the production mode of crops by genetic modification is a key strategy to improving crop yields and provides new opportunities to further investigate the effects of intercropping on plant roots and soil microbiota. Thus, this study provides a basis for selecting suitable sugarcane–soybean intercropping patterns and a theoretical foundation for a sustainable sugarcane production.

Photosynthesis, yield, energy balance, and water-use of intercropped maize and soybean.

By 2050, the U.S. Corn Belt will likely face a 23% increase in leaf‐to‐air vapor pressure deficit (VPDL), the driving force of evapotranspiration (ET), which may restrict maize yield improvements for rainfed agroecosystems. Alternative cropping systems, such as maize and legume intercrops, have previously demonstrated yield and resource‐use advantages over monocultures. In this study, the residual energy balance approach was used to gain insights into how an additive simultaneous maize and soybean intercrop system regulates ET and water‐use efficiency (WUE) compared to standard maize and soybean monoculture systems of the U.S. Corn Belt. Experimental field plots were rain‐fed and arranged in a randomized complete block design in three blocks. Photosynthetic capacity and grain yield of maize were conserved in the intercrop. However, its competitive dominance shaded 80%–90% of incident light for intercropped soybean at canopy closure, leading to a 94% decrease in grain yield compared to soybean monoculture. The total grain yield per unit area of the additive intercrop (land‐use efficiency) increased by 11% ± 6% (1 SE). Compared to maize monoculture, the intercrop had higher latent heat fluxes (λET) at night but lower daytime λET as the intercrop canopy surface temperature was approximately .25°C warmer, partitioning more energy to sensible heat flux. However, the diel differences in λET fluxes were not sufficient to establish a statistically significant or biologically relevant decrease in seasonal water‐use (ΣET). Likewise, the increase in land‐use efficiency by the intercrop was not sufficient to establish an increase in seasonal water‐use efficiency. Intercropping high‐performing maize and soybean cultivars in a dense configuration without negative impact suggests that efforts to increase yield and WUE may lead to improved benefits.

Dynamic of recovery growth of intercropped soybean after maize harvest in maize–soybean relay strip intercropping system

AbstractRecovery growth is common in relay intercropping systems and is a useful practice to increase total productivity of these systems. A field experiment was conducted during 2014–2016 to investigate the phenotypic and physiological traits related to light interception and utilization changes and cultivars difference of soybean during the recovery growth period. Two cropping patterns (maize–soybean relay strip intercropping (RSI), analogous soybean monoculture (CK)) and two soybean cultivars (shade‐tolerant Nandou12 and shade non‐tolerant Jiuyuehuang) were evaluated. During the co‐growth period, the growth of both two soybean cultivars was suppressed and showed a series of shade avoidance traits. After maize harvest, the LAI and leaflet number of intercropped soybean exhibited rapid growth, the LAI of Nandou12 (3.09) and Jiuyuehuang (1.32) recovered to 79% and 43% of corresponding CK level, respectively. Subsequently, final biomass of Nandou12 (3972.7 kg ha−1) and Jiuyuehuang (2263.3 kg ha−1) recovered 85.7% and 52% of corresponding CK level, respectively. Leaf blade thickness of Nandou12 recovered to the corresponding CK level, while Jiuyuehuang was not. Pn recovered to 84.5% and 82.8% of sole Pn at 80 days after soybean sowing in 2015 and to 72% and 91.2% at 66 days after soybean sowing in 2016 for Nandou12 and Jiuyuehuang, respectively. The above recovery process promoted the recovery of pod formation and grain yield. The yield of Nandou12 (1159.5 kg ha−1) has no significant difference between the CK level (1325.5 kg ha−1) but significantly higher than that of Jiuyuehuang (566.8 kg ha−1). Taken together, some recovery growth did occur in Jiuyuehuang, but it did not completely compensate for the growth reduction that occurred during the co‐growth period. Shade‐tolerant soybean cultivar has more stronger recovery growth ability in LAI, leaflet number, leaf thickness, and photosynthesis after maize harvest, which promoted the recovery growth of aboveground biomass and grain yield.

The yield increase and land improvement effects of different sorghum/wild soybean intercropping patterns on reclaimed coastal salt pans

The yield increase and land improvement effects of different sorghum/wild soybean intercropping patterns on reclaimed coastal salt pans

Effects of maize and soybean intercropping on nodule growth, nitrogen fixation of soybean under low phosphorus condition

Effects of maize and soybean intercropping on nodule growth, nitrogen fixation of soybean under low phosphorus condition