Sole Cropping Systems Research Articles

THE EFFECTS OF INTEGRATED SOIL FERTILITY MANAGEMENT AND CROPPING SYSTEMS ON SOIL WATER CONTENT ON SORGHUM AND COWPEA PRODUCTION IN CENTRAL HIGHLANDS OF KENYA

<p><strong>Background:</strong> Soil fertility degradation remains the major biophysical cause of declining <em>per capita</em> crop production on smallholder farmers in Central Kenya highlands. The study was carried out for 3 consecutive seasons in Embu County classified as semi-arid lands in Kenya. <strong>Objectives:</strong> To determine the effect of Soil Water Harvesting (SWH), cropping systems and Integrated Soil Fertility Management technologies on sorghum and cowpea production in Mbeere South Sub-County, Kenya. <strong>Methodology:</strong> The treatments were arranged in a factorial structure with 3 levels of SWH, 2 cropping systems and 6 soil fertility management options laid out in a partially balanced incomplete block design. The SWC was measured after 2 weeks after planting interval stages in the whole season. Data were analyzed by ANOVA and significant means separated using Least Significant Difference (LSD) at 95% Confidence Interval. <strong>Results:</strong> There was a two way interactions effect between SWH*Fertility management options on sorghum grain yields was significant (<em>p</em>=0.0027, <em>p</em>=0.0008 and<em> p</em>=0.0057) during long rains (LR) of 2011 and 2012, and short rains (SR) of 2011, respectively. Additionally, SWH methods significantly affected sorghum grain yields in a similar trend (<em>p</em>=0.002, <em>p</em>=0.0005 and<em> p</em>=0.0003) in their respective seasons. In SR 2011 and LR 2012, soil fertility options also produced significant effects (<em>p</em>=0.0047 and <em>p</em>=0.0024) on cowpea grain yields, respectively. The results further indicated that there were significant higher SWC measurements at initial stages of 2 WAP, 4 WAP and 6 WAP intervals as compared to the late stages of the season. However, sole cropping systems had significantly more SWC measurement than those in intercropping systems in both seasons. <strong>Implications:</strong> Manure added treatments positively affected SWC conservation and this could be as a result of increased soil organic carbon which improved soil fertility. The available SWC played a great role in drought effect mitigation by availing moisture to sorghum and cowpea productivity especially when prolonged dry spells coincide with crop’s sensitive phenological growing stages. <strong>Conclusions:</strong> Water harvesting methods cropping systems and soil fertility management options had positive influence on soil moisture conservation and crop yields production in Central Kenya Highland. </p>

Light distribution at the fruit tree-crop interface and consequences for yield in sloping upland agroforestry

Agroforestry can improve soil conservation and overall farm productivity compared with sole-crop systems, but its benefits are limited by competitive interactions between tree and crop components. Studies on light competition have been performed on relatively flat land, but slope can influence light distribution. Little is known about optimizing light utilization and enhancing system productivity and/or income from agroforestry on sloping land.This study examined how slope influences light distribution and performance of maize and coffee crops in fruit tree-crop agroforestry. Starting hypotheses were that 1) crops upslope of tree rows receive and intercept greater amounts of light than those downslope; and 2) position of the crop is more important for light interception and yield when fruit trees have a large, dense canopy.Five-year-old fruit-crop agroforestry experiments on west-southwest facing slopes were revisited. Each agroforestry treatment was divided into nine zones relative to the tree rows (zone 5), with zones 1–4 upslope and 6–9 downslope of the fruit tree row. Light distribution was assessed using Hemiview and SunScan and compared with that in sole-maize and sole-coffee systems. Crop growth and yield were also recorded.Incident light to the crop was higher in the sole-crop system than in agroforestry. In agroforestry, incident light to the crops was lower downslope of trees than upslope but increased with increasing distance from the tree rows. On average, 0.40–0.50 fraction of total light reached the soil surface. Downslope had a stronger negative effect on light distribution and crop yield than upslope. The available light at the soil surface provides scope for additional components. Further studies on the light demands of different crops during the season could improve system design.

Optimizing nitrogen application rates to maximize productivity while reducing environmental risk by regulating nitrogen and water utilization in mixed cropping systems

Optimizing the nitrogen (N) fertilization level and cropping system is critically important for achieving good production performance with low environmental pollution. However, there is a knowledge gap on the relationship between crop production sustainability, water and nitrogen consumption, greenhouse gas (GHG) emission under the change in N application rate under cereal and legume mixed systems. A 3-year field experiment with two cropping systems [sole forage sorghum (SS) and forage sorghum/lablab mixed cropping (SL) with four N fertilizer application rates (N0, 0 kg N ha−1; N90, 90 kg N ha−1; N180, 180 kg N ha−1; and N270, 270 kg N ha−1)] was conducted. Results obtained showed that mixed cropping combined with N fertilization enhanced forage biomass and crude protein yield by 34.0 % and 51.1 %, respectively, particularly in mixed cropping combined with the N180 treatment compared with the N0 level in the sole cropping system. Similar improvements were observed for yield stability and sustainability (2.97 % and 0.95, respectively), which reached maximum values at N180 in the mixed cropping system. In addition, mixed cropping increased the water productivity of dry matter yield (WPDM) and water productivity of crude protein yield (WPCPY) by 17.2 % and 27.6 %, respectively, at 180 kg N ha−1 compared with the corresponding treatments of the sole planting system. Furthermore, mixed cropping combined with appropriate N application significantly improved N physiological efficiency (PEN) and reduced GHG intensity (GHGI), where N application of 180 kg ha−1 N increased PEN by 21.3 % and reduced GHGI by 17.6 % compared with the corresponding monoculture in the mixed cropping system. This study demonstrated that reducing N fertilization in cereal–legume cropping systems can promote forage productivity by optimizing water and N management while decreasing environmental pollution. Therefore, forage sorghum mixed with lablab and fertilization at 180 kg N ha–1 is a preferable approach for sustainable agricultural production in the Northwest arid region of China.

DEVELOPING MULTILINE COWPEA VARIETIES ADAPTED TO LOCAL CROPPING SYSTEMS AND SPECIFIC FARMERS’ PRODUCTION GOALS THROUGH PARTICIPATORY BREEDING

<p><strong>Background</strong><strong>.</strong> Decentralized participatory breeding approach facilitate the development of varieties better suited for a diversity of farmers' contexts. To enhance breeding efficiency, formal methodological settings are needed to include, at early stage of selection, particular local practices and farmers’ preferences. <strong>Objective</strong><strong>.</strong> Evaluate how location, farmers’ profile and local cropping system could be taken into account to optimize selection of cowpea varieties in a decentralized context. <strong>Methodology:</strong> Twenty-two candidate multiline varieties of cowpea (<em>Vigna unguiculata L. </em>Walp) were developed from a biparental family of recombinant inbred lines. These varieties were subjected to selection under edaphic and climatic conditions of three locations and two cropping systems (intercropping <em>versus</em> sole cropping). Trials were carried out in collaboration with farmers' federations. Participatory evaluations were conducted over two years by the three groups of farmers defined by the following production goals: grains production as priority (“Grain priority profile”), fodder as priority (“Fodder priority profile”) and grain quality as priority (“Food processing priority profile”). <strong>Results</strong><strong>.</strong> The statistical analysis supported significant effects of location and cropping system on the agronomic traits, with interactions effects involving the variety. A strong correlation was observed between the varietal choices of the two farmers’ profiles which prioritized respectively grain and food processing. These farmers preferred varieties with higher grain yield and best grain quality. Farmers who prioritized fodder preferred more specific varieties, characterized by highest haulm yield. <strong>Implications.</strong> The clustering of farmers into specific profiles is an efficient method which allow expressing their diversified production goals through participatory evaluation. This led to more specific varietal choices for each of the profiles. <strong>Conclusion</strong><strong>.</strong> This study set cropping systems and farmer profiles as formal design factors at early breeding stage. These factors acted efficiently to support the process of varietal choice. The participatory approach highlighted the congruence and complementary between farmers’ and researchers’ knowledges. It helped identifying, for intercropping and sole cropping systems respectively, the most suitable varieties preferred by each of three respective farmers’ group.</p>

The Impacts of Planting Patterns Combined with Irrigation Management Practices on Watermelon Growth, Photosynthesis, and Yield.

(1) Background: Crop yields in China's arid and semi-arid regions are limited by water shortages. Exploring the interactions and resource utilization among agroforestry species is key to maintaining diversified agricultural production. (2) Objective: An apple-watermelon agroforestry system and watermelon sole-cropping system were compared to quantify how resource availability (light, water) and watermelon performance (leaf photosynthetic rate, growth, and yield) change with irrigation strategies. (3) Methods: A three-year apple and watermelon field experiment was conducted in a young apple orchard in the arid area of central Ningxia to test the effect of light competition and irrigation systems on light environment, leaf photosynthetic rate, plant growth, and yield in watermelon. The experiment encompassed two planting patterns: (i) apple-watermelon agroforestry (AF) and watermelon sole-cropping (SC) and (ii) three irrigation quotas (W1: 105 mm, W2: 210 mm, and W3: 315 mm). (4) Results: The results show that the agroforestry planting pattern extended the growth period of watermelon and increased the leaf area index. Mean daily shade intensity increased by 16.02% from 2020 to 2022. The land equivalent ratio (LER) was >1 in 2021 and 2022. The SWC, leaf photosynthetic rate, LAI, and yield of watermelon in an agroforestry planting pattern were lower than when in a sole-cropping planting pattern. However, under the W1 irrigation strategy, the total soluble solids of the agroforestry planting pattern were 2.27% higher than those of the sole-cropping pattern, and the yield of the agroforestry planting pattern was 2.59% higher than that of the sole-cropping pattern. Under the W3 irrigation strategy, the average watermelon weight in the agroforestry planting pattern was 2.85% higher than that of the sole-cropping pattern. A path analysis showed that the agroforestry planting pattern can increase the yield by increasing soil water content, which is different from the sole-cropping pattern. (5) Conclusions: The results confirm that the apple-watermelon agroforestry planting pattern reduced watermelon yields. However, the LER of the agroforestry system was greater than 1.0. It is reasonable to plant watermelons in young apple forests.

Response of Intercropping Sorghum (Sorghum bicolor L. Moench) with Cowpea and Nitrogen Application on Growth and Yield of Sorghum

Sorghum grain yields have remained low despite the emergence of higher yield varieties, due to inadequate soil fertility, unsuitable cropping patterns, and restricted nitrogen fertilizer application (N). Cowpea integration and N utilization in sorghum-based cropping systems are likely to boost yield. However, knowledge of the impacts of sorghum-cowpea intercropping, nitrogen usage, and their interactions on companion crop performance is lacking. The effect of sorghum-cowpea intercropping and three N rates on the growth and yield of two sorghum varieties (ETS 2752 and ETS 4946) and two cowpea varieties (Keti and Bole) was investigated in RCBD with a split-plot arrangement, replicated three times. Sorghum grain yield was positively correlated with harvest index, fertile tiller m-2, leaf area index, panicle weight, and CGR. Sorghum/cowpea intercropping was more productive than sole (LER>1). ETS 2752 was superior to ETS 4946 in terms of growth and yield, hence it is recommended to farmers for commercial production. Therefore, the sole cropping system and N addition were effective in enhancing growth and grain yield of sorghum and cowpea, hence recommended for commercial production of ETS 2752. Intercropping is only recommended for sorghum production to improve household food security since it improves land productivity (LER>1).

Pearl Millet–Groundnut Cropping Systems for the Sahel

A two-year study of pearl millet–groundnut cropping systems across two fertilizer levels was conducted in Maradi, Niger, in the Sahelian zone of West Africa. The objective of this study was to identify the best cropping system with and without fertilizer application. The experiment was conducted with ten treatment combinations of five pearl millet and groundnut cropping systems (pearl millet and groundnut sole crops, and three pearl millet—groundnut intercrops) and two fertilizer levels. Yields were approximately 300 kg ha−1 higher in the 2022 high rainfall year than in 2021, but the year did not interact with cropping systems or fertilizer application. All the intercropping systems had an LER above 1.0, and land use efficiency increased by 19 to 41%. Fertilizer application increased yields in all cropping systems by 200 to 600 kg ha−1. The government subsidy increased the value-to-cost ratio by 0.5 to 2.5 units and was required for the economic response for pearl millet sole and intercrops in 2022. The groundnut sole cropping system had the greatest economic response to fertilizer application. Based on the risky environment and multiple end uses needed by producers, the intercrop system M-G: 1:3:1 with fertilizer application is the best option to optimize pearl millet and groundnut production.

Yield Comparison of Groundnut (Arachis hypogaea L) and Corn (Zea mays L) Under Sole and Multiple Cropping Systems

Yield Comparison of Groundnut (Arachis hypogaea L) and Corn (Zea mays L) Under Sole and Multiple Cropping Systems

Evaluation of Soil Temperature, Water Productivity and Agronomic Performance of Potato (Solanum Tuberosum L.)-Legume Intercropping System in the Western Highlands of Cameroon

Intercropping is a farming practice involving two or more crop species, growing simultaneously in the same area and which could efficiently utilize natural resources. A two-year study was conducted during 2021 and 2022 in the western highlands of Cameroon to examine the impacts of potato-legume intercropped on soil water content (SWC), productivity and soil temperature(ST) in order to identify cropping systems (CS) that controls ST and water productivity (WP). A randomised complete block design with seven treatments: sole potato crop (T1), Mucuna (T2), lima bean (T3), cowpea (T4) and intercropping systems of Mucuna+potato (T5), lima bean+potato (T6) and cowpea+potato (T7) was used. CS has a significant effect (P<0.05) on ST with the lowest ST being obtained in T5 (19.50°C), T7 (19.66°C) and T6 (19.68°C) against 20.20°C in T1. SWC varied with CS (P<0.05) with T1 having the lowest SWC of 40% versus T5 (47.90%), T6 (44.42%) and T7 (42.76%). Water use increased significantly (P<0.05) with T1 (783.34mm) and decreased from T7 (783.32mm) to T5 (783.30mm). As for WP, T1 (2.96g.mm-1) recorded the lowest value and T5 (4.04g.mm-1) the highest. T5 had the highest tuber yield (29.60t.ha-1) and T1 the lowest (23.21t.ha-1). Legume grain yield and biomass were highest in T5 (2.10t.ha-1 and 6.78t.ha-1 respectively) compared to others intercropping systems. The intercropping systems obtained an overall LER and WER greater than 1 with the highest in T6 (6.20 and 2.63). Intercropping potato with Mucuna or lima bean reduces soil temperature while improving soil water productivity that enhances potato production.

Spatial distribution and association of biophysical factors with chickpea chlorotic stunt and pea seed‐borne mosaic viruses affecting legume crops in Ethiopia

AbstractFood legumes are key commodities produced in sole and mixed cropping system in Ethiopia. Their productivity has been affected recently by virus infections. Field surveys were conducted from 2018/19 to 2021/22 cropping seasons in the highlands of Ethiopia to identify major viruses and determine how biophysical factors affect disease incidence. A total of 2797 samples of chickpea (755), lentil (1683), fenugreek (111) and grass pea (248) were collected from 194 farmers' fields in Amhara (North Shewa, South Wollo and East Gojjam zones) and Oromia (East Shewa, West Shewa and North Shewa zones) regions. Laboratory testing using Tissue blot immunoassay showed that chickpea chlorotic stunt virus (CpCSV, genus Polerovirus, family Solemoviridae) and pea seed‐borne mosaic virus (PSbMV, genus Potyvirus, family Potyviridae) were the major viruses affecting legume crops in Ethiopia. The highest relative virus incidence of CpCSV (90.6%) and PSbMV (11.5%) was recorded in samples of chickpea and lentil crops, respectively. Except for crop conditions, all the independent variables significantly affected PSbMV incidence, whereas all independent variables showed a highly significant association (p < .0001) with CpCSV Incidence. A CpCSV incidence of ≥30% had a high probability of association with chickpea and fenugreek crops, the presence of aphid vectors and the 2018/19 cropping season. Similarly, PSbMV with an incidence ≥7% was highly associated with the 2018/19 cropping season. Both viruses can be managed by the combined application of cultural practices, insecticide's application, healthy seeds and resistance breeding.

Agroforestry systems in the mid-hills of the north-western Himalaya: A sustainable pathway to improved soil health and climate resilience

Identifying the new tree crop combinations plays an important function in transforming the low input agriculture into land units with high economic returns, increasing carbon (C) sink and nutrients storage capacity, and acting as a panacea to achieve Sustainability Development Goals (SDGs). The present study aims to evaluate various tree-crop combinations for (i) biomass production, (ii) carbon accumulation, and (iii) soil nutrient enrichment of traditional and commercially evolved eight agroforestry systems (AFSs), including agri-silvi-horticulture system, agri-silviculture system, silvi-pasture, fruit tree, fodder tree, bamboo, melia and poplar based AFSs with sole cropping system in the mid-hill zone of the north-western Himalaya. The results demonstrated that poplar based AFS accumulated a higher amount of biomass (130.87 Mg ha−1) and carbon (65.44 Mg ha−1) closely followed by melia-based AFS. The C stored in leaf litter was higher (0.66 Mg ha−1) in poplar-based AFS, however, soil C stock was maximum (114.69 Mg ha−1) under bamboo-based AFS. Overall, the Melia based AFS exhibited a higher rate of carbon dioxide mitigation (19.30 Mg ha−1 yr−1) and C-sequestration (5.26 Mg ha−1 yr−1) than other studied AFSs. Moreover, soil macro-nutrients (available N, P, K, S and Ca) were maximum under bamboo-based AFS, on the other hand, the fruit-based AFS had the higher concentrations of micro-nutrients i.e., Cu (3.05), Fe (31.10 mg g−1) and Mn (17.31 mg g−1). The soil microbial counts were higher in poplar-based AFS, whereas, the soil quality index improved significantly under bamboo based and fruit tree based AFSs. Hence, it can be concluded that the experimentally evolved AFSs represent an effective approach for boosting C-sequestration, soil fertility, regenerating the soil and sustainability of hill agriculture in the north-western Himalayas over traditional AFSs and sole cropping.

Suitability of Broccoli in Aonla based Multistoried Fruit Production Model

Aonla based multistoried agroforestry with vegetables is a promising solution to mitigate the devastating effects of climate change by offering multidimensional benefits. Disappointedly, Bangladeshi farmers are less equipped about the cultivation techniques, economics, and yields of multistory agroforestry production systems. Consequently, the goal of the current study was to evaluate the profitability and yield potentiality of aonla-based multistoried broccoli production system during the period of November 22 to March 23. Three separate multistory agroforestry systems were covered by the three treatments, while an open field served as the control treatment. to keep track of the system's expansion and economic success; soil analysis, photosynthetically active radiation, plant height, number of leaves, head length, head width, head weight, total yield, BCR, and LER were calculated following different established methods. While compared to sole cropping, the agroforestry approach drastically reduced the production of broccoli by 89%. Soil organic matter, nitrogen, phosphorous, potassium, and sulfur were higher in agroforestry system than that of control plot. In fact, the agroforestry system had some negative effects on the rate of crop growth in understored conditions. Despite, net return and BCR from aonla-based multistoried agroforestry system were 4-11 lakh and 2.24-3.98, which was 69-87 and 41- 67 %, respectively higher than sole cropping systems. The LER of aonla based multistoried agroforestry system was 3.20. The major conclusions show that aonla orchards can be converted to agroforestry systems to increase productivity, generate money, and protect the environment, however due to poor performance, broccoli cannot be grown in multistory systems.

Assessing the influence of furrow width on growth and yield of soybean in ridge-furrow relay intercropping system with flax

Soybean flax ridge-furrow relay intercropping system is a new method of intercropping system to distress excessive vegetative growth of soybean during the rainy season. However, the effects of furrow width for flax on growth and yield of soybean in ridge-furrow relay intercropping system remain unclear. In this study, we investigated that the effects of three treatments (FS1: 10 cm furrow width, FS2: 20 cm furrow width, FS3: 30 cm furrow width) on growth and yield of soybean and clarified informative principal data for soybean flax ridge-furrow relay intercropping system. In a three-year field experiment, soybean was grown in ridges and flax was grown in furrows. At the early vegetative growth stage of soybean, environmental conditions such as water, light, and temperature, in ridge-furrow relay intercropping system, decreased significantly by interspecific competition in comparison with sole cropping system. The differences in environmental conditions between sole cropped and intercropped treatments increased in accordance with increasing width of flax furrow. Especially, soil moisture content, photosynthetically active radiation (PAR), and temperature in FS3 were 39.9%, 29.6%, 4.4 ℃ lower than those of SS, respectively, on average of 3 years. At the reproductive growth stage, expanding furrow width for flax decreased the number of abscised leaves, plant height, leaf area index (LAI), and specific leaf area (SLA) of intercropped soybean, while increased PAR penetration within the canopy and stem diameter. At 130 DAS, average numbers of abscised leaves in FS2 and FS3 were 4 and 5 lower than that of SS, respectively. Plant height of soybean was 0.3 m lower than that of SS in both FS2 and FS3. In LAI, the value of sole cropped soybean varied between 6.8 and 7.2, but it in FS2 and FS3 varied between 3.4 and 4.3. Particularly, LAI in FS2 ranged from 4.1 to 4.3. Average stem diameter of soybean was 0.3 cm higher than that of SS in both FS2 and FS3. PAR penetration at 30 cm below soybean canopy in FS1, FS2, and FS3 was 111.2, 122.5, 133.0% of that in SS, respectively. These led to a higher crop growth rate (CGR), reproductive growth rate (RGR), and grain distribution in intercropped soybean, as compared to sole cropped soybean. Among three treatments, FS2 exhibited the maximum CGR, RGR, and grain distribution. Also, FS2 achieved maximum soybean yield of 4.9 t ha−1 (averaged by 2020, 2021, and 2022) and maximum land equivalent ratio (LER) of 2.1 (averaged by 2020, 2021, and 2022). No significant difference in LER was observed between FS2 and FS3; however, soybean yield in FS2 was significantly higher compared to FS3 across each year. Our results suggest that by selecting the appropriate furrow width, we can constrain the excessive vegetative growth more effectively and increase the yield of soybean under ridge-furrow relay intercropping system with flax.

Multi-Traits Selection of Maize Hybrids under Sole-Crop and Multiple-Crops with Soybean

Multi-trait selection is very helpful in plant breeding programs. This technique can select genotypes for specific traits. Yield performance of maize hybrids is influenced by genotype-by-environment interactions (GEIs). This requires multi-environmental testing to identify superior hybrids. The aims of this study were to: (1) select maize hybrids within favorable traits such as grain yield and yield attributes; (2) identify genotype and environment interactions (GEIs) within maize yield; (3) evaluate maize hybrids adaptability to four different locations in West Java; and (4) identify a representative environment for testing and developing new maize hybrids. Twenty-two maize hybrids were evaluated using a randomized block design repeated three times in each environment. The genotype by traits (GT) biplot showed that G3 maize hybrid was superior to ear weight (EW), ear weight without corn husk (EwoH), ear weight per plot (EWP), plant height (PH), ear diameter (ED), and 1000 seed weight (OSW) traits. The G22 maize hybrid was superior to ear weight without corn husk per plot (EwoP), ratio seed weight and ear weight without corn husk (RSEW), grain yield per ha (Y), seed weight (SW), and seed weight per plot (SWP) traits. Combined analysis of variance showed that genotype (G), environment (E), and their interactions (GEIs) had a significant effect on yield (p < 0.01) with contributions of 85.63%, 2.24%, and 12.13%, respectively. The combined stability measurement results and the GGE biplot reveal that G2 is a stable high-yield hybrid, while G4 and G16 are unstable high-yield hybrids. The most representative environment is Arjasari, with the sole-cropping system (ARJ M). This study reveals that the resulting maize hybrid can be useful as a substitute for commercial hybrids currently used. The stable high yield of maize hybrids can be recommended as new varieties with wide adaptation, while unstable high-yield hybrids can be recommended as varieties adapted to specific environments.

Pigeon Pea (Cajanus cajan L.) Based Intercropping System: A Review

Pigeon pea (Cajanus cajan L.) is a tropical and subtropical leguminous crop it is rich in protein and has high nutrient content and India is the largest producer. Pigeon pea is grown in a sole cropping system as well as with intercropping system it is majorly intercropped with legumes, cereal, and oilseed crops. Intercropping depends upon the interaction of crop species and their management. Intercropping is done between different types of cereals, pulses, and oilseed crops. Some successful cereal and pulse intercropping systems like (mung bean + maize) where, a larger equivalent yield is obtained by seeding maize following four rows of mung beans than by closer spacing. Wheat is mostly intercropped with chickpea, mustard and barley but in irrigated conditions when wheat intercropped with mustard proved more profitable than wheat intercropped with chickpea. In the Mediterranean nation, common vetch (Vicia sativa) is popularly grown with cereals. When maize and cowpea were intercropped in southern Africa, the quantity of nitrogen, phosphate, and potassium in the soil was enhanced. Maize and beans are popular in eastern Africa. However, there are many challenges while adopting intercropping for the survival of the plant. In intercropping of pigeon pea when two or more than crops are sown, they show a synergetic effect, and when it is treated with the biofertilizers like Rhizobium, arbuscular mycorrhizal fungi (AMF), phosphate-solubilizing microorganisms (PSM) and plant growth-promoting rhizobacteria (PGPR), it enhances the growth of the plant, fixes atmospheric nitrogen in the soil, availability of phosphorus to the plant increases the uptake of other micro-nutrient to the plant and plant beneficial microbes. When dual inoculation of Rhizobium and AMF is done, chlorophyll content increases in the plant.

Understanding the effects of tree-crop intercropping systems on crop production in China by combining field experiments with a meta-analysis

CONTEXTTree-crop intercropping (TCI) systems have many environmental benefits in addition to providing direct economic benefits from trees and crops. An increasing number of field experiments have provided rich basic data on crop production in TCI systems in China. However, there are fewer quantitative analysis studies on a national scale. OBJECTIVEThe purpose of this study was to investigate the effects of TCI systems on crop production in China by combining field experiments with a meta-analysis, and to understand whether the results of the field experiments and the national scale meta-analysis are consistent. METHODSThis study consists of field experiments and a national-scale meta-analysis. In the field experiments, three TCI systems were designed with different tree species configurations in Dafeng District, Yancheng city, Jiangsu Province, China, to investigate their effects on the crop yield when compared with a sole cropping system. Furthermore, we conducted a meta-analysis of 36 studies with 94 comparisons in Chinese fields to examine the effects of TCI systems on crop yields and to explore how climatic conditions, crop species, tree species, and tree characteristics affect crop yields in TCI systems. RESULTS AND CONCLUSIONIn the field experiments, TCI systems had negative effects on crop yield, and understory crop yield was affected by the tree species in the TCI systems; the crop yield in the three TCI systems was 18.9–32.2% lower than that in the sole cropping system. The meta-analysis results were consistent with those of the field experiments. In the national scale meta-analysis, TCI systems had negative effects on crop yields in China (effect size = −0.488, 95% CIs = −0.576 to −0.401), and the TCI systems decreased crop yields by 38.6% overall when compared with sole cropping systems. Furthermore, the effects of TCI systems on crop yields were different among regions, climatic conditions, crop species, tree species, and tree characteristics. TCI systems should be designed carefully considering local climates, crop species, tree species, and tree characteristics to maximize agronomic and environmental benefits. SIGNIFICANCEThis study has the potential to enhance our understanding of TCI systems in China by integrating field experiments and meta-analysis. These results can inform the development of more effective and sustainable agricultural practices.

Breeding Cowpea for Adaptation to Intercropping for Sustainable Intensification in the Guinea Savannas of Nigeria

Cowpea is a multifaceted crop; however, considerable challenges affect the production of this crop despite its comparatively better adaptation to harsh environments. Most smallholder farmers in West Africa cultivate this crop in intercropping systems where its low plant population does not allow the full expression of the cultivars’ yield potential. This is because most varieties currently grown in intercrop have been developed in and for monocropping, although some breeding programs recently have focused on intercrop systems. This study, therefore, aimed to evaluate the performance of some newly developed cowpea breeding lines for adaptation to intercropping systems. Firstly, an on-station field experiment was conducted in 2018. The selected promising lines and a standard check were evaluated in three locations in an intercropping system and on-farm trials. Significant differences were observed among the cowpea genotypes for all the traits measured. Two improved lines, UAM14-122-17-7 and UAM14-123-18-3, had superior grain and fodder yields under sole and intercropping systems and in different agroecological systems, revealing their adaptability. Based on our findings, UAM14-122-17-7 and UAM14-123-18-3 are recommended for a cereal-cowpea mixture because they are adapted to intercropping and produce high-grain yield under intercrop and sole-cropping systems.

Economic Analysis of Cocoa Production Cropping Pattern in Nigeria, West Africa

Cocoa is the most prominent export crop in Nigeria in terms of its production and export capacities. There is dearth of literature on the profitability of the different cropping systems. This study therefore examined the profitability of the different cocoa cropping systems and the factors that affect the revenue of cocoa farmers for each of the cropping systems. The study area was Nigeria and information were collected from one hundred and eighty farmers using well-structured question- naires. Descriptive statistics, budgetary analysis and linear regression were used for analysis in this study. The study revealed that twenty-seven farmers practised sole cocoa cropping, seventy-five farmers practised cocoa/arable cropping and seventy-eight farmers practised cocoa/tree cropping systems, respectively. The mean age of farmers in sole cocoa cropping system was 49.3 years, for cocoa/ arable cropping system the mean age was 47.8 years while for cocoa/tree cropping system the mean age of farmers was 47.2 years. For sole cocoa cropping system, the total cost (TC) was USD 7,764; the gross revenue (GR) was USD 43,774 with USD 36,009 as profit made from the cropping system. The TC for cocoa/tree cropping system in Nigeria was USD 18,003, GR was USD 124,104 and the profit was USD 106,102. Similarly for cocoa/arable cropping system, the TC was USD 16,215, GR was USD 109,849 and profit was USD 93,634. The determinants for the three cocoa cropping systems were age, gender, marital status (married), educational level (primary), cost of seedling, cost of fertilizer, cost of fungicide, cost of herbicide, labour cost for bush clearing, land preparation, weeding and planting. Cocoa/tree and cocoa/arable cropping systems were more profitable than sole cocoa cropping systems. However, cocoa/ tree cropping system was more profitable with a value of USD 106,102.

Simultaneous Assessment of Water and Nitrogen Use Efficiency in Rain-Fed Chickpea-Durum Wheat Intercropping Systems

It is well known that multiple interactions can occur between nitrogen and water use, depending on climate, soil and crop characteristics, in crop growth and yield development. However, little is known about the simultaneous change in both water and N use efficiency (WUE and NUE) and their possible interactions in cereal–-legume intercropping systems. In order to advance our knowledge on the N and water facilitation mechanisms involved in the intercropping responses of N and water input co-limitations, we investigated, via four experiment years, the simultaneous optimization of water and N-fertilizer inputs, as well as its possible effects on growth, yield, N acquisition, and the NUE and WUE in intercropped species. The results indicated that intercropping increases the leaf area index by more than +0.14 and +1.03 units when compared to durum wheat and chickpea monoculture systems, respectively. This increase is particularly noticeable under higher rainfalls during the crop period (i.e., as can be seen in the 2022, 2020, and 2019 seasons). Moderate N-application enhanced both the grain yield and protein accumulation in the mixed crops by more than 0.22 t ha−1 and 57 kg ha−1, respectively. Conversely, intercropping significantly decreased the mixed grain yield when compared to durum wheat monocultures. Intercropping advantages in terms of biomass (ranged from 1 to 44%) and N-acquisition (2 to 91%) was confirmed in either low- (2021) or high- (2019 and 2022) rainfall growing periods, but only under low and moderate N-applications. Improving N nutrition under both rainfall and drought growth periods was confirmed only for the mixed crops under all applied N-fertilizer doses. Such improvements in growth, N acquisition, and yield quality were most likely achieved by positive interactions (r2 = 0.73, p ≤ 0.001) between the NUE and WUE for the chickpea–wheat intercropping. Thus, 0.62 kg m−3 of WUE promotes a significant increase of 1 kg kg−1 in NUE by mixing chickpea-durum wheat. Rain-fed chickpea-durum wheat intercropping provides a higher performance in growth and yield quality compared to sole cropping systems; this may occur from the simultaneous optimizations of both water and N fertilizer inputs in low-N soil under semiarid conditions.

Understanding the Impact of the Intercropping System on Carbon Dioxide (CO2) Emissions and Soil Carbon Stocks in Limpopo Province, South Africa

Understanding the carbon dioxide emission rates under different agricultural practices is a critical step in determining the role of agriculture in greenhouse gas emissions. One of the challenges in advocating for an intercropping system as a sustainable practice in the face of climate change is the lack of information on how much CO2 is emitted by the system. A factorial randomized complete block design study was set up at two distinct agroecological locations (Syferkuil and Ofcolaco) in the Limpopo Province of South Africa to investigate carbon dynamics in sorghum-cowpea intercropping and sole cropping system over two seasons. Intercropping system emitted less CO2 compared to sole cropping system. In 2018/19 at Syferkuil and 2020/21 at Ofcolaco, intercropping systems emitted 11% and 19% less CO2, respectively, than sole cropping systems. In both agroecological regions, low cowpea density consistently resulted in higher CO2 emissions than high density. During the 2018/19 cropping season, sorghum emitted more CO2 of 5.87 t·ha−1 than cowpea with 5.14 t·ha−1 in a sole cropping system at Syferkuil. Cowpea, on the other hand, emitted more CO2 of 6.5 t·ha−1 and 10.18 t·ha−1 than sorghum during the 2020/21 cropping season at Syferkuil and Ofcolaco, respectively. Furthermore, intercropping improved the carbon emission efficiency (CEE) of the individual crops in the system. The treatments used in the intercropping and sole cropping systems had a significant impact on the strength of the relationship between carbon stocks and CEE. Our results revealed that sorghum-cowpea intercropping system at a relatively higher cowpea density in a no-till system reduces the amount of CO2 lost to the atmosphere. The system can thus, be promoted as one of the sustainable farming practices to reduce emissions and improve carbon storage in the soil.