Intercropping Planting Research Articles

Impact of Intercropping Five Medicinal Plants on Soil Nutrients, Enzyme Activity, and Microbial Community Structure in Camellia oleifera Plantations.

Intercropping medicinal plants plays an important role in agroforestry that can improve the physical, chemical, and biological fertility of soil. However, the influence of intercropping medicinal plants on the Camellia oleifera soil properties and bacterial communities remains elusive. In this study, five intercropping treatment groups were set as follows: Curcuma zedoaria/C. oleifera (EZ), Curcuma longa/C. oleifera (JH), Clinacanthus nutans/C. oleifera (YDC), Fructus Galangae/C. oleifera (HDK), and Ficus simplicissima/C. oleifera (WZMT). The soil chemical properties, enzyme activities, and bacterial communities were measured and analyzed to evaluate the effects of different intercropping systems. The results indicated that, compared to the C. oleifera monoculture group, YDC and EZ showed noticeable impacts on the soil chemical properties with a significant increase in total nitrogen (TN), nitrate nitrogen (NN), available nitrogen (AN), available phosphorus (AP), and available potassium (AK). Among them, the content of TN and AK in the rhizosphere soil of Camellia oleifera in the YDC intercropping system was the highest, which was 7.82 g/kg and 21.94 mg/kg higher than CK. Similarly, in the EZ intercropping system, the content of NN and OM in the rhizosphere soil of Camellia oleifera was the highest, which was higher than that of CK at 722.33 mg/kg and 2.36 g/kg, respectively. Curcuma longa/C. oleifera (JH) and Clinacanthus nutans/C. oleifera (YDC) had the most effect on soil enzyme activities. Furthermore, YDC extensively increased the activities of hydrogen peroxide and acid phosphatase enzymes; the increase was 2.27 mg/g and 3.21 mg/g, respectively. While JH obviously increased the urease activity, the diversity of bacterial populations in the rhizosphere soil of the intercropping plants decreased, especially the Shannon index of YDC and HDK. Compared with the monoculture group, the bacterial community abundance and structure of JH and YDC were quite different. The relative abundance of Actinobacteriota and Firmicutes was increased in YDC, and that of Acidobacteriota and Myxococcota was increased in JH. According to the redundancy analysis (RDA), pH, total potassium, and soil catalase activity were identified as the main factors influencing the microbial community structure of the intercropping systems. In conclusion, intercropping with JH and YDC increased the relative abundance of the dominant bacterial communities, improved the microbial community structure, and enhanced the soil nutrients and enzyme activities. Therefore, in the future, these two medicinal plants can be used for intercropping with C. oleifera.

Determinants of oilseed rape-service plant intercropping performance variability across a farmers’ fields network in Western Switzerland

The intercropping of winter oilseed rape with frost-sensitive service plants can provide a diversity of services including weed control and N supply for oilseed rape. This practice started to be adopted by farmers and has therefore become one of the most popular intercropping in Western Europe. However, in Switzerland, such intercropping leads to contrasting yields. The growth of service plants and the benefits they provide have also been found to be variable. The factors explaining these variabilities remain unclear. Our study aimed to better understand this variability under a temperate climate thanks to the regional agronomic diagnosis framework. In this study, we first investigated the main factors explaining this variability and then aimed to rank them to identify ways to better manage such intercropping systems. A network of 28 farmers’ fields planted with winter oilseed rape intercropped with service plant mixtures was studied. Farmers’ practices were diverse in terms of specific composition of the service plant mixture, pest management, and fertilization. We observed that the growth of oilseed rape and service plants in fall was highly variable. We determined that in late fall, the main drivers of the service plant mixture dry weight were specific composition of the mixture and precipitation. The introduction of buckwheat in the service plant mixture enhanced its late fall biomass. The oilseed rape grain yields ranged from 0.4 to 5.0 t ha−1 and were lower than that of the local reference in 75% of the fields. This was mainly explained by insect pest damage in spring due to a very limited use of insecticide in our field network combined with a lack of alternative pest management strategies. This work provides further elements to investigate the causes leading to the high variability we observed, together with the local observations that will benefit the farmers.

Macrogenomics-Based Analysis of the Effects of Intercropped Soybean Photosynthetic Characteristics and Nitrogen-Assimilating Enzyme Activities on Yield at Different Nitrogen Levels.

Currently, China's soybean self-sufficiency rate is only 15%, highlighting the soybean crisis and the supply chain risks that pose a major threat to China's food security. Thus, it has become imperative to step up efforts to boost soybean production capacity while promoting the green and sustainable development of regional farmland ecosystems. In this context, the present study comprehensively investigated the effects of intercropping and nitrogen application rate on soybean yield, as well as the changes in gradients generated by different levels of nitrogen application. Based on six consecutive years of maize-soybean intercropping planting patterns, the inter-root soils of soybeans were collected at the flowering stage and evaluated for soil nitrogen content, nitrogen-assimilating enzyme activities, and microbial community composition of soybean, which were correlated with yield, to clarify the main pathways and modes of intercropping effects. The N2 level (80 kg·ha-1) was favourable for higher yield. In comparison to monocropping, the intercropping reduced yield by 9.65-13.01%, photosynthetic characteristics by 1.33-7.31%, and plant nitrogen-assimilating enzyme activities by 8.08-32.01% at the same level of N application. Likewise, soil urease and catalase activities were reduced by 9.22 and 1.80%, while soil nitrogen content declined by an average of 6.38%. Gemmatimonas and Bradyrhizobium enrichment significantly increased soil nitrogen content, photosynthetic characteristics, and soybean yield, while it was reduced by Candidatus_Udaeobacter and Candidatus_Solibacte enrichment. The results of this study provide a theoretical basis for further optimising maize-soybean intercropping, which is crucial for enhancing the agricultural production structure and improving the overall soybean production capacity.

Rational Maize–Soybean Strip Intercropping Planting System Improves Interspecific Relationships and Increases Crop Yield and Income in the China Hexi Oasis Irrigation Area

Abundant light and heat in the Hexi Oasis Irrigation Area in China provide superior natural conditions for agricultural development. To study the maize–soybean planting system of intercropping and determine superior group yield and economic benefits in the Hexi Oasis Irrigation Area, eight treatments were set up in 2022–2023: maize–soybean intercropping with a bandwidth of 1.8 m and a row ratio of 2:3 (M1S3), a bandwidth of 1.8 m and a row ratio of 2:4 (M1S4), a bandwidth of 2.0 m and a row ratio of 2:3 (M2S3), a bandwidth of 2.0 m and a row ratio of 2:4 (M2S4), a bandwidth of 2.2 m and a row ratio of 2:3 (M3S3), a bandwidth of 2.2 m and a row ratio of 2:4 (M3S4), monocropping maize (M), and monocropping soybean (S). We analyzed the effects of changes in bandwidth–row ratios on photosynthetic characteristics, yield, and interspecific relationships in these treatments during two crop reproductive periods. Our results showed the following: (1) Under the intercropping system, the photosynthetic capacity of maize was highest when the row ratio was 2∶3 and bandwidth was 1.8 m. The net photosynthetic rate (Pn) increased by 1.72% to 48.90%, the transpiration rate (Tr) increased by 5.53% to 118.10%, and stomatal conductance (Gs) increased by 2.82% to 86.49% compared with other planting systems. Increasing the bandwidth from 1.8 m to 2.2 m improved the photosynthetic characteristics of soybean, increasing Pn, Tr, and Gs by 3.44% to 74.21%, 3.92% to 53.69%, and 2.41% to 55.22%, respectively. (2) The yield of maize and soybean under monocropping was significantly higher than that under intercropping. In the intercropping treatments, the average yield of crops in the M3S3 system was 16,519.4 kg ha−1, an increase of 6.48% compared with the M3S4 system, indicating that the reduction of one row of soybean in the same bandwidth system increases crop yield; The average economic benefit of the M3S3 system over two years was 35,171.73 CNY ha−1, which increased by 13.3 and 80% compared with the average economic benefit of maize and soybean monocropping, indicating that the intercropping system leads to better economic results for farmers than monocropping. (3) In the two-year experiment, the land equivalent ratio (LER) was highest in the M3S3 model, averaging 1.25 over the two years, showing better land productivity compared with other intercropping systems. (4) When bandwidth was 1.8, 2.0, or 2.2 m, the LER decreased by 8.3, 5.9, and 5.6% when planting an additional row of soybeans, the relative crowding coefficient of soybeans in the respective bandwidths increased by 4.59, 4.72, and 0.75%, the competition ratio of maize (CRM) increased by 22.94, 16.97, and 12.74%, the competition ratio of soybean (CRS) decreased by 20.47, 17.61, and 16.78%, and the competitive power of maize was greater than that of soybean, indicating that the increase in soybean rows in the same bandwidth system would weaken the competitive advantage of soybean, resulting in crop yield and economic benefit reduction. When the row ratio was 2:3 or 2:4, bandwidth increased from 1.8 m to 2.2 m, LER decreased by 3.31 and 0.86%, intercropping maize aggressiveness (AM) decreased by 7.55 and 12.50%, CRM decreased by 18.04 and 24.84%, and CRS increased by 17.32 and 22.77%, respectively, which indicated that the increase in bandwidth under different row ratio systems could improve the competitive advantage of intercropping soybean, thereby improving crop yield and economic benefits. (5) The AHP method, entropy weight method, and TOPSIS analysis showed that M3S3 ranked first, with the highest comprehensive evaluation (0.6017). In conclusion, the M3S3 planting system can better coordinate crop interspecies relationships, with higher land yield and economic benefit, and can be used as a suitable maize–soybean intercropping system in the Hexi oasis irrigation area.

Identification and Characterization of Colletotrichum truncatum and C. destructivum Causing Stem Rot of White Clover in China.

White clover (Trifolium repens L.) is an excellent quality forage legume species with superior planting efficiency, which reduces the cost of artificial weeding and nitrogen fertilizer inputs, and has feeding and economic value. However, from June to September 2022, severe stem rot affected the yield and quality of white clover crops in Harbin, Heilongjiang Province, China. The aim of this study was to identify the causative agents of the disease. Overall, Colletotrichum truncatum (6 isolates) and C. destructivum (10 isolates) were obtained from rotten white clover stems and identified based on morpho-molecular characteristics and phylogenetic analyses. Pathogenicity tests of the isolates revealed that C. destructivum had a higher pathogenicity to white clover than C. truncatum. In addition, all isolates were highly pathogenic to broad bean, fodder soybean, soybean, pak choi, and chickpea, were pathogenic to mint, and did not infect corn, wheat, or cilantro. C. destructivum and C. truncatum isolates were very sensitive to tebuconazole and pyraclostrobin, with EC50 values of 0.54 to 0.70 μg/ml and 0.42 to 0.62 μg/ml, respectively, efficacies ranging between 93.2 to 94.9% and 90.2 to 95.2% at 600 μg/ml and 450 μg/ml, respectively, and EC90 values of 1.88 to 13.36 μg/ml and 1.32 to 23.39 μg/ml, respectively. Therefore, intercropping of host and nonhost plants and chemicals can be considered to control stem rot in white clover. These results provide a basis for controlling C. destructivum and C. truncatum in white clover in China.

Effects of narrow-wide row planting patterns on canopy photosynthetic characteristics, bending resistance and yield of soybean in maize‒soybean intercropping systems

With the improvements in mechanization levels, it is difficult for the traditional intercropping planting patterns to meet the needs of mechanization. In the traditional maize‒soybean intercropping, maize has a shading effect on soybean, which leads to a decrease in soybean photosynthetic capacity and stem bend resistance, resulting in severe lodging, which greatly affects soybean yield. In this study, we investigated the effects of three intercropping ratios (four rows of maize and four rows of soybean; four rows of maize and six rows of soybean; six rows of maize and six rows of soybean) and two planting patterns (narrow-wide row planting pattern of 80–50 cm and uniform-ridges planting pattern of 65 cm) on soybean canopy photosynthesis, stem bending resistance, cellulose, hemicellulose, lignin and related enzyme activities. Compared with the uniform-ridge planting pattern, the narrow-wide row planting pattern significantly increased the LAI, PAR, light transmittance and compound yield by 6.06%, 2.49%, 5.68% and 5.95%, respectively. The stem bending resistance and cellulose, hemicellulose, lignin and PAL, TAL and CAD activities were also significantly increased. Compared with those under the uniform-ridge planting pattern, these values increased by 7.74%, 3.04%, 8.42%, 9.76%, 7.39%, 10.54% and 8.73% respectively. Under the three intercropping ratios, the stem bending resistance, cellulose, hemicellulose, lignin content and PAL, TAL, and CAD activities in the M4S6 treatment were significantly greater than those in the M4S4 and M6S6 treatments. Compared with the M4S4 treatment, these variables increased by 12.05%, 11.09%, 21.56%, 11.91%, 18.46%, 16.1%, and 16.84%, respectively, and compared with the M6S6 treatment, they increased by 2.06%, 2.53%, 2.78%, 2.98%, 8.81%, 4.59%, and 4.36%, respectively. The D-M4S6 treatment significantly improved the lodging resistance of soybean and weakened the negative impact of intercropping on soybean yield. Therefore, based on the planting pattern of narrow-wide row maize‒soybean intercropping planting pattern, four rows of maize and six rows of soybean were more effective at improving the lodging resistance of soybean in the semiarid region of western China.

Do We Listen or Ignore Indigenous Practices? The Machobane Farming System - An Indigenous Farming Practice of Lesotho

Aim: To evaluate the adaptive capacity of the Machobane Farming System, an indigenous practice to improve soil fertility and maize productivity compared to other non-Machobane farming practices. Study design: The study was conducted in four agroecological zones of Lesotho: Mountain, Foothills, low lands and Senqu river valley. Soil samples were collected at random from the non-Machobane farming practicing fields and Machobane farming practicing fields and the soil physicochemical and microbiological analyses were conducted to evaluate the soil quality. Structured and non-structured questionnaires were used to gather information from Focus Group Discussion (FGD) on the type of farming practices used and other demographic data. Results and Discussion: The MfS were found to be less affected and resilient to climate change with multiple benefits such as moisture conservation, slow release of nutrients and cross migration of microorganisms to the intercropping plants in the field unlike other farming practicing fields. An increased number of soil fertility indicator microorganisms such as Bacillus spp and Nitrogen fixing bacteria were seen to have increased the production of food crops (P>0.05) almost all the year round. An intensive relay cropping of one acre would be sufficient to ensure food security for an average family of 5 members. Conclusion: Currently, the Machobane Farming System (MfS) is adopted by many households in Lesotho using biochar and compost.

Hexose/pentose ratio in rhizosphere exudates-mediated soil eutrophic/oligotrophic bacteria regulates the growth pattern of host plant in young apple-aromatic plant intercropping systems.

The positive effect of intercropping on host plant growth through plant-soil feedback has been established. However, the mechanisms through which intercropping induces interspecific competition remain unclear. In this study, we selected young apple trees for intercropping with two companion plants: medium growth-potential Mentha haplocalyx Briq. (TM) and high growth-potential Ageratum conyzoides L. (TA) and conducted mixed intercropping treatment with both types (TMA) and a control treatment of monocropping apples (CT). Our findings revealed that TM increased the under-ground biomass of apple trees and TA and TMA decreased the above-ground biomass of apple trees, with the lowest above-ground biomass of apple trees in TA. The above- and under-ground biomass of intercrops in TA and TMA were higher than those in TM, with the highest in TA, suggesting that the interspecific competition was the most pronounced in TA. TA had a detrimental effect on the photosynthesis ability and antioxidant capacity of apple leaves, resulting in a decrease in above-ground apple biomass. Furthermore, TA led to a reduction in organic acids, alcohols, carbohydrates, and hydrocarbons in the apple rhizosphere soil (FRS) compared to those in both soil bulk (BS) and aromatic plant rhizosphere soil (ARS). Notably, TA caused an increase in pentose content and a decrease in the hexose/pentose (C6/C5) ratio in FRS, while ARS exhibited higher hexose content and a higher C6/C5 ratio. The changes in exudates induced by TA favored an increase in taxon members of Actinobacteria while reducing Proteobacteria in FRS compared to that in ARS. This led to a higher eutrophic/oligotrophic bacteria ratio relative to TM. This novel perspective sheds light on how interspecific competition, mediated by root exudates and microbial community feedback, influences plant growth and development.

Effects of the Host Plants of the Maize-Based Intercropping Systems on the Growth, Development and Preference of Fall Armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae).

In this paper, the effects of maize and its three intercropping plants, sweet potato, soybean and peanut, on the growth and development of FAW, feeding preference of larvae, olfactory response and oviposition preference of adults were studied in the laboratory. The results showed that maize and peanut were suitable for the survival and development of FAW, while sweet potato and soybean were not suitable for multigenerational reproduction. The larvae significantly preferred to feed on maize compared to the other three plants. The olfactory response test indicated that soybean showed a strong deterrent effect against FAW adults. Furthermore, the intercropping plants reduced the host selection rate of adults compared to maize alone. In two-choice tests of the maize vs. the intercropping plants, the female adult preferred to oviposit and lay more eggs on maize rather than on the intercropping plants. The intercropping plants significantly reduced the oviposition selection of FAW adults when the combination (maize + intercropping plant), especially soybean and sweet potato, was compared to maize alone. These may be the reasons for why the maize-soybean intercropping system reduced FAW damage in the field. We also speculated that the maize-sweet potato system may also reduce the FAW damage. This study provided a theoretical basis for the comprehensive management of FAW by utilizing an intercropping system.

Intercropping on Mars: A promising system to optimise fresh food production in future martian colonies.

Future colonists on Mars will need to produce fresh food locally to acquire key nutrients lost in food dehydration, the primary technique for sending food to space. In this study we aimed to test the viability and prospect of applying an intercropping system as a method for soil-based food production in Martian colonies. This novel approach to Martian agriculture adds valuable insight into how we can optimise resource use and enhance colony self-sustainability, since Martian colonies will operate under very limited space, energy, and Earth supplies. A likely early Martian agricultural setting was simulated using small pots, a controlled greenhouse environment, and species compliant with space mission requirements. Pea (Pisum sativum), carrot (Daucus carota) and tomato (Solanum lycopersicum) were grown in three soil types ("MMS-1" Mars regolith simulant, potting soil and sand), planted either mixed (intercropping) or separate (monocropping). Rhizobia bacteria (Rhizobium leguminosarum) were added as the pea symbiont for Nitrogen-fixing. Plant performance was measured as above-ground biomass (g), yield (g), harvest index (%), and Nitrogen/Phosphorus/Potassium content in yield (g/kg). The overall intercropping system performance was calculated as total relative yield (RYT). Intercropping had clear effects on plant performance in Mars regolith, being beneficial for tomato but mostly detrimental for pea and carrot, ultimately giving an overall yield disadvantage compared to monocropping (RYT = 0.93). This effect likely resulted from the observed absence of Rhizobia nodulation in Mars regolith, negating Nitrogen-fixation and preventing intercropped plants from leveraging their complementarity. Adverse regolith conditions-high pH, elevated compactness and nutrient deficiencies-presumably restricted Rhizobia survival/nodulation. In sand, where more favourable soil conditions promoted effective nodulation, intercropping significantly outperformed monocropping (RYT = 1.32). Given this, we suggest that with simple regolith improvements, enhancing conditions for nodulation, intercropping shows promise as a method for optimising food production in Martian colonies. Specific regolith ameliorations are proposed for future research.

Management of the Lati Petangis grand forest park (TAHURA): roles and perceptions of forest farmer groups

This research aims to identify and descriptively analyze the roles and perceptions of Forest Farmers Groups in the management of Tahura Lati Petangis in Batu Engau District, Paser Regency. This research uses a quantitative descriptive approach. The sample in this study consisted of all members of the three Forest Farmers Groups located around the Tahura Lati Petangis area, totaling 52 people. The results showed that the role of the Forest Farmer Group, which is a partner in the management of Tahura Lati Petangis, is to make efforts to restore the ecosystem and make efforts to manage forests sustainably in the form of Agroforestry, where partnerships with forest farmer groups are carried out in the form of work orders. While the perception of the Forest Farmer Group in the management of Tahura Lati Petangis shows that this partnership is very beneficial for forest farmer groups, they also get insight, skills, and wages from the Tahura Lati Petangis management, because they have planted and maintained the main plant, namely forest plants, and besides that, they also get additional income from planting intercrops and coaching from the Tahura Lati Petangis management.

Trait-based cropping of brassicaceous plants: Effects on ecosystem services and crop yield

Diversification of agroecosystems through mixed cropping can facilitate multiple ecosystem services that may improve yields. Intercrops may repel pests and nourish natural enemies while trap crops lure pests away from target crops. A small-scale agricultural field experiment was conducted in 2018 and 2020 in Finland to study how intercropping of brassicaceous plants and faba bean (Vicia faba) affects yield and quality of a target crop (white cabbage (Brassica oleracea var. capitata)), herbivory on the target crop, and effects of the insect communities linked to the observations. The study was conducted with five different plot arrangements in each year. Broccoli (Brassica oleracea var. italica) or turnip (Brassica rapa var. rapa) were located at the perimeters of 6 × 6 m plots as trap crops. They were planted either alone or with yellow rocket (Barbarea sp). Faba bean was planted as an intercrop in the most complex designs. Cabbage head fresh weight was greatest in the most complex plot type, which included cabbage, broccoli, yellow rocket and faba bean and the head weight was significantly greater than in the cabbage monocrop or the plots with a broccoli-only trap crop. Turnip was included in the experiment in 2020 and efficiently attracted flea beetles and pollen beetles. In 2020, the turnip trap crop alone and the most complicated designs with broccoli or turnip combined with yellow rocket and faba bean significantly reduced P. xylostella abundance in the middle of the plot. Possibilities to use trait-based cropping systems in white cabbage production are discussed.

The impact of main Areca Catechu root exudates on soil microbial community structure and function in coffee plantation soils.

Coffee is an important cash crop worldwide, but it has been plagued by serious continuous planting obstacles. Intercropping with Areca catechu could alleviate the continuous planting obstacle of coffee due to the diverse root secretions of Areca catechu. However, the mechanism of Areca catechu root secretion in alleviating coffee continuous planting obstacle is still unclear. The changes of coffee rhizosphere soil microbial compositions and functions were explored by adding simulated root secretions of Areca catechu, the primary intercropping plant species (i.e., amino acids, plant hormone, organic acids, phenolic acids, flavonoids and sugars) in current study. The results showed that the addition of coffee root exudates altered soil physicochemical properties, with significantly increasing the availability of potassium and organic matter contents as well as promoting soil enzyme activity. However, the addition of plant hormone, organic acids, or phenolic acids led to a decrease in the Shannon index of bacterial communities in continuously planted coffee rhizosphere soil (RS-CP). The inclusion of phenolic acids specifically caused the decrease of fungal Shannon index. Plant hormone, flavonoids, phenolic acids, and sugars increased the relative abundance of beneficial bacteria with reduced bacterial pathogens. Flavonoids and organic acids increased the relative abundance of potential fungal pathogen Fusarium. The polyphenol oxidase, dehydrogenase, urease, catalase, and pH were highly linked with bacterial community structure. Moreover, catalase, pH, and soil-available potassium were the main determinants of fungal communities. In conclusion, this study highlight that the addition of plant hormone, phenolic acids, and sugars could enhance enzyme activity, and promote synergistic interactions among microorganisms by enhancing the physicochemical properties of RS-CP, maintaining the soil functions in coffee continuous planting soil, which contribute to alleviate the obstacles associated with continuous coffee cultivation.

Agronomic assessment of three spice plants as understorey crops in oil palm (Elaeis guineensis Jacq.) plantation

Utilization of land with intercrop plants can support the productivity of the land. The wide spacing of oil palm plants can be used to plant intercrops. Spice plants such as red ginger, turmeric, and cardamom are examples of intercropping plants under the shade of oil palm. This study aimed to determine the adaptability of red ginger, turmeric, and cardamom as understorey plants of different oil palm ages. The research was carried out from February to November 2021 at Sekernan, Muaro Jambi, Jambi. The study consisted of three experiments to investigate three spice plants. Each experiment used a randomized complete block design (RCBD) with oil palm ages as treatments, namely 0, 5, 10, 15, and 20 years. Variables observed included light intensity, plant height, tiller number, leaf number, and rhizome weight. The red ginger and turmeric were considered as adaptive plants to understorey conditions due to the yield of > 60% in 15-year-old oil palm trees than those grown in non-shade conditions. Production levels of red ginger and turmeric were determined by the number of tillers and leaves. The cardamom plant under oil palm shade produced a better yield than that in control. This implies that all three spices are suitable as intercrop plants under oil palm plantations.
 Keywords: cardamom; low light intensity; red ginger; shade stands; turmeric

Effect of rhizobium inoculation on rhizosphere phosphorous dynamics and fertilised phosphorous use efficiency in a maize–pigeon pea intercropping system in weathered tropical soil

AbstractIntroductionLow phosphorus (P) use efficiency (PUE) of fertiliser is a critical problem in sustainable crop production, especially in strongly weathered tropical soils with a high P‐fixation capacity. Both intercropping and rhizobium inoculation have shown to improve the P availability of rhizosphere soil, but the effect of a combined approach of using both intercropping and rhizobium inoculation is still unclear. In this study, we aimed to evaluate the effect of rhizobium inoculation on the soil–plant P dynamics and fertilised PUE under the intercropping system in strongly weathered tropical soil.Materials and MethodsWe conducted an 85‐day cultivation pot experiment with pigeon pea (PP) and maize using highly weathered tropical soil under eight treatments: monocropping (CS) or intercropping, with or without rhizobium (Bradyrhizobium elkanii USDA61) inoculation (−I, +I) and with or without P fertilisation (0P, 50P) (2 × 2 × 2 = 8 treatments). We evaluated the effects of intercropping and rhizobium inoculation on plant growth parameters, P dynamics of the rhizosphere and bulk soil using the Hedley P fractionation method, the amount of organic acid from plant roots as a plant P‐mobilising capacity, and fertilised PUE.ResultsTotal plant P uptake per pot was significantly increased by intercropping but not by combining intercropping and rhizobium inoculation, resulting in better fertilised PUE only in intercropping. The available inorganic P (Pi) and less labile Pi of the soil were higher in the rhizosphere than those in the bulk by intercropping under 50P and were similar in PP + I under 50 P. The amount of organic acid per pot under 50P increased with each treatment, that is, intercropping and rhizobium inoculation, but not with their combination.ConclusionThe intercropping system has a strong potential to improve PUE by stimulating the P‐mobilising capacity of intercropping plant roots, whereas rhizobium inoculation of the intercropping system did not improve PUE in this study.

Intercropping with alfalfa and co-inoculation of AMF and PGPR improve growth, yield, grain bioactive quality, and soil fertility of barley

ABSTRACT The use of intercropping systems and beneficial microorganisms to improve the performance of crops constitutes a promising strategy. In this context, a pot experiment was conducted to evaluate the effects of intercropping and inoculation with arbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria (PGPR) on the performance of barley and alfalfa plants and soil health. Three inoculation treatments (for both monocropped and intercropped plants) and the control were used: (1) AMF-inoculated plants; (2) PGPR-inoculated plants; (3) AMF+PGPR co-inoculated plants. Combining intercropping and AMF+PGPR co-inoculation improved shoot and root dry weight by 167% and 300% in barley and by 712% and 617% in alfalfa, respectively, compared to the controls. Similarly, in barley intercropped and inoculated with AMF+PGPR, the number of grains per spike and the thousand-grain weight were enhanced by 124% and 122%, respectively. Applying intercropping and co-inoculation of AMF+PGPR increased the protein, total phenolic, and flavonoid contents of barley grains by 99%, 132%, and 343%, respectively. The contents of soil nitrogen and phosphorus were improved by 387% and 270% in barley soil and by 359% and 212% in alfalfa soil, respectively, compared to monocultures.

Evaluasi efektivitas tanaman repelen dalam pengendalian penggerek batang Apomecyna saltator F. (Coleoptera: Cerambycidae) pada tanaman labu madu dengan pola tanam tumpang sari

Apomecyna saltator Fabricius (Coleoptera: Cerambycidae) merupakan hama tanaman labu madu yang keberadaannya perlu dikendalikan. Namun, informasi mengenai hama ini masih sangat terbatas. Pengendalian dengan penerapan pola tumpang sari memiliki prospek dan perlu dikembangkan untuk pengendalian hama ini sebagai bagian integral dari pengembangan pengendalian hama terpadu A. saltator. Penelitian ini dilakukan untuk mengetahui pengaruh pola tanam tumpang sari tanaman labu madu dengan beberapa tanaman repelan terhadap persentase infestasi, populasi larva/pupa A. saltator, dan produksi labu madu. Penelitian ini dirancang dengan rancangan acak kelompok (RAK) yang terdiri atas 4 perlakuan, yaitu monokultur tanaman labu madu (A); tumpang sari tanaman labu madu dan serai (B); tumpang sari tanaman labu madu dan kunyit (C); tumpang sari tanaman labu madu dan bawang daun (D). Setiap perlakuan diulang sebanyak 6 kali. Hasil menunjukkan bahwa rata-rata persentase infestasi A. saltator sampai 56 hari setelah tanam (HST) untuk semua perlakuan berkisar 72–79,6%. Populasi larva/pupa A. saltator berkisar 107–128 individu/9 tanaman. Produksi labu madu berkisar 21,97–26,75 kg/9 tanaman. Dari hasil penelitian ini disimpulkan bahwa tanaman kunyit, serai, dan bawang daun tidak berpengaruh terhadap persentase infestasi, populasi A. saltator, dan produksi labu madu.

Mycorrhiza Diversity in Some Intercropping Systems of Potato (Solanum tuberosum L) and Faba Bean (Vicia faba L)

Arbuscular mycorrhizal fungi (AMF) is the most widely distributed mycorrhizal fungi in the soil and can make a symbiosis with the roots of host plants to form arbuscular mycorrhizal symbionts. Intercropping is a practice of polyculture cropping where two or more plant species are simultaneously cultivated in the same field. The objective of this study was to define the effect of intercropping on the density and diversity of mycorrhizal spores. In this study, potatoes and faba beans, both of which have the ability to symbiosis with mycorrhizae, were intercropped. A randomized group design with 5 planting system treatments was employed in this study with 5 replications. The results concluded that density of mycorrhizal spores in the intercropping planting pattern was not statistically different from the density of mycorrhiza in the monoculture cultivation pattern. The types of mycorrhiza found included the genus of Glomus, Funneliformis, Scutellospora, Cetraspora, Septoglomus, and Entrophospora Keywords: pH; Root exudate; Spore density, Spore identification; Spore diversity.

INFLUENCE OF INTERCROPPING ON SOIL MICROBIAL ACTIVITY AND STRAWBERRY DEVELOPMENT

Strawberry is one of the most important berry crop grown around the world and their consumption increases every year. The introduction of new practices promoting farm sustainability and long-term soil health in strawberry production systems is very essential. Towards environment- and climate-friendly farming practices intercropping can be used to improve soil microbiological activity and biodiversity, and reduce the use of pesticides and mineral fertilizers, while the right choice of intercropped plants is of great importance to achieve these goals. The trials on strawberry intercropping were established in Latvia in 2021. Three treatments with different intercropping plant rotations, including crimson clover, pea, garlic, marigold, and winter rye mix with vetch, were compared to conventional strawberry growing using straw mulch. Trial was installed in three locations: two organic farms and the Institute of Horticulture (LatHort). Thus representing climatically different regions and different soil conditions. Strawberries were grown in 1.2 m distant rows, where in the intercropping treatments, each second interrow was occupied by companion plants. Soil microbial activity was evaluated during vegetation seasons by determining soil respiration rate (SRR) and dehydrogenase activity (DHA) several times per season in 2021 and 2022. Strawberry vegetative development was evaluated at the end of each vegetation season. During the investigation period, soil microbial activity fluctuated during vegetation seasons, depending on growing conditions. In 2021, SRR varied from 1.9 – 3.3 CO2 mg L- 1, while in 2022, from 2.1 - 3.4 CO2 mg L-1. DHA varied from 46 – 134 INTF, µL×????−1 × h in 2021 and 60 – 101 INTF, µL×????−1 × h in 2022. Intercropping had low influence on microbial activity and results differed within each location. Strawberry plant biomass differed among locations and treatments with the highest above-ground biomass observed in LatHort during second growing season in conventional growing system (790 g plant-1).

Intercropping of aromatic plants in truffle orchards: short-term effect on extraradical truffle mycelium and aromatic plant growth

Intercropping of aromatic plants in truffle orchards: short-term effect on extraradical truffle mycelium and aromatic plant growth