Intercropping Treatments Research Articles

Agroecosystem Management on Green Mustard Plants in Wetlands during Dry Season

This research aimed to find a pattern of agroecosystem management that can increase arthropod diversity, production, and Return Cost Ratio (RCR) values in organic wetlands planted during the dry season. This research was set in Randomized Block Design (RAK) with seven treatments and five repetitions, namely: 1) Intercropping between green mustard and basil, with chicken manure and without<em> </em><em>Bacillus thuringiensis</em>; 2) Intercropping between green mustard and basil with water hyacinth compost, and without <em>B. thuringiensis</em>; 3) intercropping between green mustard and leek, given water hyacinth compost, and without application <em>B. thuringiensis</em>; 4)Intercropping between green mustard and leek, given chicken manure, and without application <em>B. thuringiensis</em>; 5) Intercropping between green mustard and leek, given chicken manure, and given <em>B. thuringensis</em> application, doubled of recommended dosage; 6) Intercropping between green mustard and leek with chicken manure, and <em>B. thuringensis</em> application according to recommended dosage; 7) Monoculture of green mustard without organic fertilizer and without the application <em>B. thuringiensis. </em>From this research, it was concluded that the pattern of agroecosystem management of green mustard that can increase arthropod diversity in organic wetlands planted during dry season was the intercropping treatment between green mustard with basil, together with chicken manure and without <em>B. thuringiensis</em>. Meanwhile, the pattern of agroecosystem management of green mustard that can increase the production of green mustard and RCR value on the organic wetlands planted in the dry season was the intercropping treatment between green mustard with leek, together with chicken manure, and without <em>B. thuringiensis</em>.

Economic Analysis of the Corn Intercropped With Marandu Grass as a Function of Azospirillum brasilense Application

The Integrated Agricultural Production Systems (IAPS) under No-Tillage System (NTS), add values to grain production and to livestock activity over the year, besides providing reestablishment of degraded areas. The objective of this work was to evaluate the production costs and profitability of the irrigated corn crop, intercropped or not with Urochloa brizantha cv. Marandu, inoculated or not with Azospirillum brasilense, in the lowland Cerrado. The work was composed of two sequential experiments, conducted in Selvíria-MS, from 2015 to 2016. The experimental design of the two experiments was in randomized blocks with four replicates. The first experiment consisted of six treatments: (a) inoculate crop in single crop, (b) single corn crop without inoculation, (c) intercropping without inoculation, (d) intercropping with inoculation in both seeds, (e) intercropping with inoculation of corn seeds, and (f) intercropping with inoculation of grass seeds. In the corn off-season harvest, for the second experiment, the experimental units with grass were subdivided into three treatments: (a) leaf inoculated grass (250 mL of inoculant), (b) grass broadcast fertilized with urea (200 kg of N ha-1 year-1) in broadcast and (c) grass without fertilization or inoculation. The inputs were the most expensive components in corn production. In the intercropping treatments, where the grass was destined for silage, the profitability indexes were positive, enabling the system regardless of Azospirillum brasilense inoculation.

Effects of intercropping with post-grafting generation of Impatiens balsamina on photosynthesis of grape seedlings under cadmium stress

To study the effects of intercropping with post-grafting generation of Impatiens balsamina on photosynthesis of grape seedlings, a plurality of photosynthesis indicators of the grape were measured by a pot experiment. The results showed that intercropping with ungrafted and post-grafting generation of I. balsamina all reduced the photosynthesis parameters of grape to some extent. After four intercropping treatments, the net photosynthetic rate (Pn), stomatal conductance (Gs), CO2 concentration of intercellular (Ci), transpiration rate (Tr) and value of pressure deficit leaf (Vpdl) were all lower than that of grape monoculture. Therefore, intercropping with post-grafting generation of I. balsamina could not improve but reduce the photosynthesis of grape seedling.

Effects of grape seedlings intercropping with post-grafting generation of Impatiens balsamina on different fractions of cadmium content in soil

To study the effects of grape seedlings intercropping with post-grafting generation of Impatiens balsamina on different fractions of cadmium (Cd) in soil, a pot experiment was conducted. The results showed that grape seedlings intercropping with post-grafting generations of I. balsamina significantly increased the content of exchangeable Cd in soil. Grape seedlings intercropping with the post-grafting generation of self-rooted grafting by two different sizes seedlings of I. balsamina significantly increased the content of residual Cd (52%), and increased the exchangeable Cd content (19%). In conclusion, grape seedlings were not suitable for intercropping with post-grafting generations of I. balsamina, although some intercropping treatments increased the content of residual Cd.

Cover Crops Enhance Natural Enemies While Help Suppressing Pests in a Tea Plantation

Abstract Tea is an economically important crop, consumed by billions of people. Despite the increasing market for pesticide-free products, the use of pesticide in tea is still high. In order to investigate whether intercropping promotes biological control organisms, Chamaecrista rotundifolia (Pers.) Greene, Indigofera hendecaphylla Jacq., Trifolium repens L., and Vigna sinensis (L.) were separately intercropped with free weeding as control in a tea plantation at Yangli, China. Arthropods were collected by taking sweep-net samples, and treatment effects on assemblages were investigated. The combined species richness of all arthropods and that of parasitoids was significantly increased in intercropped treatments while the species richness of herbivores and predators was only greater in C. rotundifolia and I. hendecaphylla intercropped treatments. Compared with control, the combined abundance of all arthropods, and that of herbivores was lower, while the abundance of parasitoids and its taxa was greater in all intercropped treatments. The abundance of predators and its taxa was greater only in tea plantations intercropped with C. rotundifolia or I. hendecaphylla. Of the herbivores, the abundance of Empoasca onukii Matsuda, Sternorrhyncha, Aleyrodidae, and Pentatomidae was greater in the areas intercropped with C. rotundifolia in comparison with the control, but the abundance of Thysanoptera and Geometridae caterpillars was lower. The recorded increase in the abundance of beneficial arthropods may explain the lower abundance of Thysanoptera or Geometridae caterpillars detected in the intercropped tea plantations. Our results indicate that intercropping has the potential to enhance arthropod biodiversity, and to provide an option for sustainable pest control in tea plantations.

Shading and intercropping with buffelgrass pasture affect soil biological properties in the Brazilian semi-arid region

The objective of this work was to evaluate the changes caused by shading and intercropping with a legume (Clitoria ternatea L.) in a grass (Cenchrus ciliaris L.) pasture on the microbiological and biochemical attributes of the soil. Microbial biomass carbon (MB-C), soil respiration, the activities of soil enzymes (β‑glucosidase, acid phosphatase and urease) and total soil fungal and bacterial were evaluated. Soil samples were collected at four periods: before intercropping (BI), at 120, 165 and 210 days of cultivation and under four shading levels 0 (full sun), 26, 39 and 55%. Before intercropping (BI), shading affected biological and biochemical parameters by increasing the MB-C but reducing soil respiration, resulting in a reduction of qCO2. There was an increase in MB-C and β‑glucosidase in the intercropping treatment and 39% shading, while under monoculture an increment in MB-C was reached only under 55% shading at 120 days of cultivation. The highest CO2 fluxes by soil respiration were observed in the intercropping areas and in the shaded areas at 0, 26 and 39% at 120 days of cultivation. The intercropping system and the higher levels of shading reduced the qCO2 at all sampling time. The highest soil urease activity occurred in the intercropping areas and in full sunlight, regardless of the sampling time, while acid phosphatase presented greater activity in the intercropped areas at 165 days of cultivation. From the multivariate analysis, it was possible to verify that the effects of intercropping are evident at 165 days of cultivation with the formation of two distinct groups and an increase in the biological quality in the intercropped areas. For qPCR it was verified that only shading affected the amounts of total soil fungi and bacteria; the use of shading reduced the amount of fungi only at 120 days, while for bacteria, the use of 26% shading in the BI period and full sun at 165 days increased the amount of bacteria. This variation of shading effect over time on the amount of fungi and bacteria may indicate changes in the composition of fungal and bacterial species. It is concluded that shading and intercropping with C. ternatea into C. ciliaris pasture promotes improvements in soil quality indicators under semi-arid conditions.

Effects of Intercropping with Post-Grafting Generation of Cosmos sulphureus on Total Potassium Content in Grape Seedling under Cadmium Stress

The effects of intercropping with post-grafting generation of Cosmos sulphureus on total potassium content of grape seedling were investigated through pot experiment under cadmium stress. The results showed that the intercropping treatments had significant effect on soil available potassium content and total potassium content in root, stem and leaf of grape seedling, while intercropping with ungrafted and post-grafting generation of C. sulphureus all decreased the potassium content of grape seedling and soil compared with grape monoculture. The potassium content of grape seedling and soil were all ranked as: grape monoculture (MG) > intercropping with the ungrafted generation of C. sulphureus (UG) > intercropping with the post-grafting generation of C. sulphureus of self-rooted grafting by the same one seedling (PSG) > intercropping with the post-grafting generation of C. sulphureus of self-rooted grafting by two different sizes seedlings (PSDG) > intercropping with the post-grafting generation of C. sulphureus of self-rooted grafting by two same sizes seedlings (PSSG). Therefore, intercropping with post-grafting generation of C. sulphureus could not increase but reduce the potassium content, which is one of essential minerals that contributes to plant growth and development.

Effects of climate variability on insect pests of cabbage: adapting alternative planting dates and cropping pattern as control measures

BackgroundConsidering the potential impact of climate change on the ecology of insect pests, different planting dates and cropping patterns were investigated as farm-level adaption to control insect pests of cabbage and improve productivity.MethodsThis is a 3 × 4 factorial experiment setup in randomized complete block design including three planting dates (early, normal and late) and four cropping patterns (control—sole cabbage or tomato, tomato intercrop, Piper emulsion and insecticide) with four replications each.ResultsCabbage infestation ranged from 1 to 29 and correlated negatively with planting dates or treatments, which differed (P < 0.001) significantly across planting dates, treatments and their interaction, with the highest during early planting. Diamondback moth larvae correlated negatively with planting dates or treatments, ranging from 0 to 13 that differed significantly (P < 0.001) across planting dates, treatments and their interaction. Looper larvae correlated negatively with treatments, ranging from 0 to 8 that differed significantly (P < 0.001) across planting dates, treatments and their interaction, with highest during normal planting and lowest during late planting. Webworm larvae correlated negatively with planting dates or treatments, ranging from 0 to 13 that differed significantly (P < 0.001) across planting dates, treatments and their interaction. The number of sprouted plants ranged from 0 to 6 and differed significantly (P < 0.001) across planting dates, treatments and their interaction, with the highest in early planting for control that differed significantly from late planting. Cabbage yield correlated positively with planting dates and ranged from 2.8 to 6.0 tons per hectare that differed significantly (P < 0.001) across planting dates, treatments and their interaction, with the highest during normal and late planting dates.ConclusionThe interaction of planting dates and Piper emulsion or intercropping treatments can be effectively used as control measure for insect pests of cabbage leading to greater yield, with late planting as viable farm-level adaptation to climate variability.

Effects of Intercropping with Post-Grafting Generation of Impatiens balsamina on Nitrogen Uptake of Grape Seedlings under Cadmium Stress

A pot experiment was conducted to study the effects of intercropping with post-grafting generation of Impatiens balsamina on nitrogen content in each part of grape seedlings and the alkaline nitrogen content in soil. Results showed that under cadmium stress, intercropping with post-grafting generation of I. balsamina (intercropping with I. balsamina of non-grafting, intercropping with post-grafting generation of self-rooted grafting by the same one seedlings of I. balsamina intercropping with post-grafting generation of self-rooted grafting by the two same sizes seedlings of I. balsamina intercropping with post-grafting generation of self-rooted grafting by the two different sizes seedlings of I. balsamina) reduced the nitrogen content in each part of the grape seedlings compared with monoculture. But all the intercropping treatment increased the soil alkaline nitrogen content compared with monoculture. In conclusion, intercropping with post-grafting generation of I. balsamina reduced the nitrogen content of grape seedlings and increasing the soil alkaline nitrogen content.

Competition for 15N-labeled nitrogen in a jujube tree (Zizyphus jujuba Mill.)/wheat (Triticum aestivum L.) agroforestry system in northwestern China

The degree of tree-crop competition for nitrogen (N) and its effect on fertilizer-use efficiency and N movement were examined in a jujube tree (Zizyphus jujuba Mill.)/wheat (Triticum aestivum Linn.) agroforestry system during 2011–2012. Assessment of competition was accomplished via the installation of an experiment with five imbedding depths (20, 40, 80, 120 and 200 cm) of 15N-enriched CO(NH2)2 and two configuration patterns (sole and intercropped treatment). The percentage of N derived from fertilizer (NDFF) and fertilizer-use efficiency (UFN) were determined using 15N-enriched CO(NH2)2 (5.22% atom enrichment) applied at 8 g N per plant. Land equivalent ratios of the jujube/wheat intercropping system reached maximum ratios of 1.45 for grain (fruit) yield and 1.67 for biomass in 2011 and 1.38 for grain (fruit) yield and 1.59 for biomass in 2012. The alley cropping yield decreased significantly compared to sole-cropped plants in both years, as did the biomass of intercropped wheat in 2012. This study showed a significant difference in nitrogen acquisition between intercropping and the expected value for the various depths in both years. The %NDFF of the two plants showed significant differences between intercropping and the expected value at various depths in both years, and the intercropped %NDFF was higher than the expected value. The total UFN data, which represented an increase in response to intercropping, indicate that plants in the intercropping treatment had a higher UFN than the expected value. The UFN for jujube trees in all treatments was lower than that for wheat, indicating less uptake and utilization of N fertilizer. Management interventions, particularly those that increase fertilizer in the shallow layer may be critical for the success of this system.

Intercropping Arundo donax with Woody Plants to Remediate Heavy Metal-Contaminated Soil

A greenhouse experiment was conducted to study the potential of intercropping Arundo donax with Broussonetia papyrifera or Morus alba to remediate heavy metal-contaminated soil. The results showed that intercropping the herbaceous plant A. donax with woody plants B. papyrifera or M. alba was beneficial for plant growth on heavy metal-contaminated soil. This can effectively enhance the comprehensive enrichment capacity of heavy metals and improve soil enzyme activities. The photosynthetic pigment contents in the leaves of A. donax, B. papyrifera, and M. alba decreased along with remediation time under monoculture treatment for each plant. However, compared with 90 d cultivation, the chlorophyll-a and carotenoid contents in B. papyrifera leaves and chlorophyll-b and carotenoid contents in M. alba leaves under intercropping treatment after 270 d cultivation were only slightly changed. Furthermore, chlorophyll-a, chlorophyll-b, and carotenoid contents in M. alba leaves under intercropping treatment were significantly (P<0.05) increased by 99.1%, 177.1%, and 119.9%, respectively, compared with monoculture-treated M. alba, and the total biomass of M. alba increased significantly (P<0.05) by 26.1%. Compared with monoculture-treated A. donax, the total accumulation amounts of Pb and Zn in the shoots of combined plants was significantly (P<0.05) enhanced by 171% and 124% under intercropping treatment of A. donax with B. papyrifera. Compared with monoculture-treated M. alba and A. donax, the total accumulation amounts of As and Pb in the shoots of intercropped plants were significantly (P<0.05) enhanced by 150% and 76.5%, respectively, under intercropping treatment of A. donax with M. alba. Moreover, the fractions of As, Cd, Pb, and Zn in contaminated soil slightly changed under intercropping treatment of A. donax with B. papyrifera or M. alba, and soil urease, acid phosphatase, and total phosphatase activity was superior to part of the monoculture treatments after 270 d cultivation. The results further suggested that intercropping A. donax with B. papyrifera or M. alba could be effectively used for heavy metal-contaminated soil remediation, while simultaneously improving the biological quality in contaminated soil.

Wheat-Maize Intercropping With Reduced Tillage and Straw Retention: A Step Towards Enhancing Economic and Environmental Benefits in Arid Areas.

Intercropping is considered a promising system for boosting crop productivity. However, intercropping usually requires higher inputs of resources that emit more CO2. It is unclear whether an improved agricultural pattern could relieve this issue and enhance agricultural sustainability in an arid irrigation area. A field experiment using a well-designed agricultural practice was carried out in northwest China; reduced tillage, coupled with wheat straw residue retention measures, was integrated with a strip intercropping pattern. We determined the crop productivity, water use, economic benefits, and carbon emissions (CEs). The wheat-maize intercropping coupled with straw covering (i.e., NTSI treatment), boosted grain yield by 27–38% and 153–160% more than the conventional monoculture of maize and wheat, respectively, and it also increased by 9.9–11.9% over the conventional intercropping treatment. Similarly, this pattern also improved the water use efficiency by 15.4–22.4% in comparison with the conventional monoculture of maize by 45.7–48.3% in comparison with the conventional monoculture of wheat and by 14.7–15.9% in comparison with the conventional intercropping treatment. Meanwhile, NTSI treatment caused 7.4–13.7% and 37.0–47.7% greater solar energy use efficiency than the conventional monoculture of maize and wheat, respectively. Furthermore, the NTSI treatment had a higher net return (NR) by 54–71% and 281–338% and a higher benefit per cubic meter of water (BPW) by 35–51% and 119–147% more than the conventional monoculture of maize and wheat, respectively. Similarly, it increased the NR and BPW by 8–14% and 14–16% in comparison with the conventional intercropping treatment, respectively. An additional feature of the NTSI treatment is that it reduced CEs by 13.4–23.8% and 7.3–17.5% while improving CE efficiency by 62.6–66.9% and 23.2–33.2% more than the conventional monoculture maize and intercropping treatments, respectively. We can draw a conclusion that intercropping maize and wheat, with a straw covering soil surface, can be used to enhance crop production and NRs while effectively lowering CO2 emissions in arid oasis irrigation region.

Field microclimate and yield for proso millet intercropping with mung bean in the dryland of Loess Plateau, Northwest China.

Based on the ecological environment features of Loess Plateau, we examined field microclimate characteristics and yield of four different intercropping patterns for proso millet (P) and mung bean (M) including 2:2, 4:2, 4:4, 2:4. The results showed that, compared with monoculture, intercropping increased plant height, leaf area index (LAI) and chlorophyll content (SPAD) of proso millet in its late growth stage, while LAI and SPAD of mung bean decreased due to the shade of the high proso millet. Mung bean appeared spindly growth for a while by increasing the plant height. Moreover, upper canopy illumination and air temperature during grain filling stage of proso millet decreased under intercropping conditions, but relative humidity substantially increased. These changes regulated soil temperature and light leakage, which decreased under intercropping systems, and thereby led to a cold and wet ecological environment. Poor atmospheric and light conditions formed a relative closure growth environment for mung bean, which suppressed its growth. The panicles, spike length, grain mass per plant and 1000-grain mass of proso millet under 2P2M, 4P2M, 4P4M and 2P4M treatments was significantly increased by 7.5%-45.0%, 2.2%-12.2%, 35.4%-94.0% and 2.3%-4.7%, respectively. This caused a 5.6%-20.7% increase of yield than the mono-culture. The branch number, pods per plant, grain mass per plant and 100-grain mass in mung bean were decreased under different intercropping treatments, and the yield was significantly reduced by 34.8%. Land equivalent ratios (LER) of each intercropping pattern were all greater than 1. Among them, LER of 2P4M was the maximum (1.86), and 2P4M treatment held relatively reasonable composite configuration. Our results suggested that 2:4 ratio of proso millet/mung bean intercropping patterns performed better than other ratios on the Loess Plateau.

Yoncanın Farklı Karışık Ekim Uygulamaları Altındaki Performansı

This study was aimed to determinate the yield and quality pattern of alfalfa stand under different intercropping treatments. Alfalfa was intercropped with sorghum-sudangrass hybrid, soybean, cowpea, and buckwheat at seed ratio of 100%:100%, 100%:80% or 100%:60%, and 100% alfalfa was used as control. The experiment was arranged in randomized block design with three replications and conducted at the research field of Yozgat Bozok University located in inner Anatolia, Yozgat-Turkey. Alfalfa and companion crops were sown as binary mixtures with 60 cm row distance in the spring of 2015. All the data was collected in the establishment year and the first production year (2016). Hay yield, protein yield, ADF (Acid detergent fiber), NDF (neutral detergent fiber), Ca, Mg, P and K content were investigated in all the treatments. Alfalfa intercropped sorghum-sudangrass hybrid at 100%:60% seed ratio produced the highest hay yield both in the establishment year (18.25 t ha-1) and the first production year (17.91 t ha-1). This study showed that intercropping increased hay and protein yield of alfalfa stand compare to sole alfalfa with the significant effect of companion crop and seed ratio.

Pemupukan NPK Phonska dan Jenis Tumpang Sari Terhadap Pertumbuhan Tanaman Pisang Rutai (Musa borneensis Becc.)

Rutai banana plants are local plants from Kutai Kartanegara Regency. But the existence of this plant has begun to be rare in the farmer's garden. Rutai bananas are small and are very popular for many people because of their distinctive aroma and sweet taste with high vitamin content. The small fruit shape is very suitable to be an appetizer at restaurants or food stalls. The Kutai Kartanegara District Government has made Rutai banana as an obligatory appetizer in Kutai Kartanegara. From the results of research on rutai banana fertilization on farmers' land shows very high productivity so it is necessary to do research to determine the growth of rutai banana planted intercropping with food crops. This is because the rutai banana plant uses a spacing of 3 mx 3 m, so that between banana plants there is still room that can be used for cultivation of food crops. This study aims to examine the effectiveness of NPK Phonska fertilization and the type of intercropping in rutai banana cultivation. This study used a Randomized Block Design (RBD) consisting of 4 treatments with 5 replications. Intercropping treatment consists of 4 levels, namely: s0 = without intercropping, without fertilization, s1 = without intercropping and NPK Phonska fertilizer 0.5 kg / tree, s2 = intercropping of chili and Phonska NPK 0.5 kg / tree , s3 = intercropping of corn plants and 0.5 kg / tree Phonska NPK fertilizer. Data obtained from observations were analyzed by variance and further testing with BNT at the level of 5%. Research activities include (1) land preparation (2) planting rutai banana seeds and ginger seedlings (3) Phonska NPK fertilizer treatment (4) Bioculture fertilizer treatment (5) POC Nasa fertilizer treatment (6) maintenance (7) data collection. The results showed that NPK Phonska fertilization was 0.5 kg / tree and intercropping with corn plants showed the best growth of rutai banana.

Intercropping of Gramineous Pasture Ryegrass (Lolium perenne L.) and Leguminous Forage Alfalfa (Medicago sativa L.) Increases the Resistance of Plants to Heavy Metals

Intercropping can increase the biomass of plants and reduce the accumulation of heavy metals in plants. However, the mechanisms of intercropping increasing plant biomass and resistance to heavy metals are still unclear. Therefore, the pot experiment had been conducted to investigate the effect of intercropping treatment on the growth of gramineous pasture ryegrass (Lolium perenne L.) and leguminous forage alfalfa (Medicago sativa L.) in metal-contaminated soil. Our results showed that intercropping alleviated inhibition of heavy metals to plant growth and increased nitrogen and chlorophyll contents in the shoots and roots. Moreover, the Pb concentrations in the shoots and roots of ryegrass and alfalfa in the intercropping were significantly lower than those in the monoculture. And, the contents of saccharase and alkaline phosphatase were significantly increased in the intercropping treatment. Additionally, the intercropping treatment could reduce the oxidative damage and increase enzymatic antioxidant activities to improve the resistance of plants in contaminated soil. The intercropping treatment can increase the resistance of plants to heavy metals through reduction of plant oxidative damage and increase of antioxidant activity. It could provide us with a strategy that intercropping of ryegrass and alfalfa can increase biomass and reduce the absorption of Pb on forage plants.

Global warming potential from maize and maize-soybean as affected by nitrogen fertilizer and cropping practices in the North China Plain

Nitrogen fertilizer is required to meet grain targets, but the fossil fuel consumption and greenhouse gas emissions resulting from its use are a barrier to achieve low C agriculture. The objective of this study is to evaluate the net global warming potential (GWP) of maize and soybean monoculture and maize-soybean intercrop systems with an ecosystem-level C budget and determine the optimal N fertilizer requirement of maize-soybean intercrop based on the GWP in CO2 -eq during cropping season. The field experiment had five treatments: maize and soybean monoculture receiving 240 kg N ha−1 and maize-soybean intercrop receiving 120, 180 and 240 kg N ha−1 for three years (2012, 2013, and 2014). Considering greenhouse gas (GHG: CO2, CH4 and N2O) emissions from the field plots, indirect GHG emissions from agricultural inputs (e.g., fertilizer, diesel and pesticides) and CO2 fixation by crops, soybean monoculture was the net C source due to its lower net primary production, while all maize monoculture and intercrop treatments were net C sinks except for the maize-soybean intercrop receiving 240 kg N ha−1 in 2013. Maize monoculture was the largest C sink due to its higher net primary production, even though it had significantly (p < 0.05) greater direct and indirect GHG emission than of the maize-soybean intercrop treatments with lower N rates. Nitrogen fertilizer contributed to direct and indirect GHG emissions, with peak N2O fluxes from field plots up to two weeks after N fertilization and 26%–74% of indirect emission attributable to N fertilizer use. Higher N fertilizer rates did not improve yield in the maize-soybean intercrop, and the nitrogen-scaled GWP showed that maize-soybean intercrops fertilized with 150–182 kg N ha−1 had a comparable C fixation potential to maize monoculture receiving 240 kg N ha−1. In conclusion, we demonstrate the ability of maize-soybean intercrop to function as a C sink, similar to maize monoculture, in the North China Plain.

Effects of mutual intercropping on cadmium accumulation by the accumulator plants Conyza canadensis, Cardamine hirsuta, and Cerastium glomeratum

ABSTRACTIn this study, three cadmium (Cd) accumulator species (Conyza canadensis, Cardamine hirsuta, and Cerastium glomeratum) were co-cultured in Cd-contaminated soil in pots to study the effects of intercropping on co-remediation. Only C. canadensis intercropped with C. glomeratum, C. hirsuta intercropped with C. glomeratum, and three-species intercropping increased plant biomass compared with their respective monocultures. The treatments of C. canadensis intercropped with C. glomeratum and three-species intercropping increased the Cd contents in roots and shoots of C. canadensis, whereas the other intercropping treatments decreased or had no significant impact on Cd contents. As for Cd accumulation, the treatments of C. canadensis intercropped with C. glomeratum, C. hirsuta intercropped with C. glomeratum, and three-species intercropping increased Cd accumulation in a single plant compared with that of their respective monocultures, whereas other intercropping treatments decreased Cd accumulation in individual plants. Only the treatments of C. canadensis intercropped with C. glomeratum and C. hirsuta intercropped with C. glomeratum increased Cd accumulation in shoots of a single pot compared with that of their respective monocultures. Therefore, C. canadensis intercropped with C. glomeratum and C. hirsuta intercropped with C. glomeratum may improve the phytoremediation efficiency for Cd-contaminated soil.

Intercropping Halophytes to Mitigate Salinity Stress in Watermelon

Saline irrigation water can lead to salt buildup and reduced crop yields. Halophytic plants are known to accumulate excess salts in tissues, removing them from the immediate environment. This two-phase experiment explored the feasibility of intercropping watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai var. lanatus) with halophytic species to mitigate the negative effects of saline irrigation water while providing a value-added crop. In the first experiment, six greenhouse-grown species were irrigated with water that was either deionized (0 dS m−1) or contained 3 or 6 dS m−1 of salts for 41 days and screened for growth and salt removal. Two halophytes were selected to be additively intercropped with watermelon under field conditions and irrigated with the same saline irrigation levels as the first experiment. Results indicated that garden orache (Atriplex hortensis L.) exhibited the highest growth rates and purslane (Portulaca oleracea L.) accumulated high amounts of sodium in plant tissues under saline irrigation. The field experiment showed that watermelon yields, stem water potential, and fruit quality were not affected by saline irrigation; however, the watermelon/orache intercropping treatment had significantly higher yields. These results suggest intercropping with halophytes has the potential to contribute a value-added crop without reducing watermelon yields.

Productivity and profitability of soybean based millets intercropping systems

A field experiment was conducted at Agricultural Research Station, Bailhongal, Belagavi district, Karnataka on mixed red and black medium soil during kharif 2016 to study the productivity and profitability of soybean and millets (foxtail millet, finger millet and little millet) under different row proportions. The experiment was laid out in RCBD with 10 treatment combinations replicated thrice. Millets were intercropped with soybean at different row proportions (2: 1 and 4: 2) along with sole millets and soybean. Sole soybean recorded significantly higher grain yield (2, 255 kg/ha) over intercropping treatments. Among the intercropping systems, soybean grain yield was higher in 4: 2 row ratio of soybean+foxtail millet (1, 697 kg/ha) followed by 2: 1 row ratio of soybean+foxtail millet (1, 673 kg/ha). Sole foxtail millet recorded significantly higher grain yield (1, 901 kg/ha) than other treatments. Among the intercropping treatments, soybean+foxtail millet in 4: 2 row proportion recorded significantly higher grain yield (1, 429 kg/ha) and it was on par with 2: 1 row ratio of soybean+foxtail millet (1419 kg/ha). Among various intercropping treatments, the highest soybean equivalent yield and land equivalent ratio (LER) were recorded in 4: 2 row ratio of soybean+foxtail millet (2, 334 kg/ha, 1.50 respectively). It was on par with 2: 1 row ratio of soybean+foxtail millet (2, 310 kg/ha, 1.49, respectively). While ATER was highest in 4: 2 row ratio of soybean+little millet (1.48) and it was on par with 2: 1 row ratio of row ratio of soybean+little millet (1.46). Significantly higher net returns and B: C ratio were recorded in 4: 2 row ratio of soybean+foxtail millet (Rs. 68, 457/ha and 2.45, respectively) and it was on par with 2: 1 row ratio of soybean+foxtail millet (Rs. 66, 779/ha and 2.40, respectively).