Increased Nutrient Uptake Research Articles

Response to Addition of Lighting Duration and Electrical Induction in Lettuce (Lactuca sativa L.) Plant on the Uptake of Nitrogen, Phosphors, Potassium and Yield

Background: The impact of excessive use of chemical fertilizers and pesticides causes problems of land degradation, low fertility levels and reduced cation exchange capacity. To increase nutrient uptake and yield of lettuce plants, cultivation techniques using induction and additional lighting are needed. The aim is to increase nutrient absorption and plant yields. Methods: The research design used a split plot with Factorial Randomized Groups. Factor 1 Lighting duration (P) for 4 and 8 hours per day and Factor 2, induction with DC (Direct Current) current (S). Induction 1 time per day (S1); The treatment in this study was repeated 4 times. Induction 2 times per day (S2) and Induction 3 times per day (S3). Result: The combination P2S2 showed good results regarding the uptake of Nitrogen (20.1 Kg.Ha-1), Phosphorus (2.71 Kg.Ha-1) and Potassium (67.23 Kg.Ha-1) in plant leaves. The P1S2 treatment showed a leaf area of (1652.19 cm2). The adding 4 hours of light and an induction interval of 2 times per day gave good results on the uptake of Nitrogen, Phosphorus and Potassium in the leaf of lettuce plants.

Effects of phosphorus fertilizer type and dripline depth on root and soil nutrient distribution, nutrient uptake, and maize yield under subsurface drip fertigation

ContextSubsurface drip irrigation can potentially increase nutrient uptake by altering the spatial distribution of nutrients and roots, but the efficiency enhancement potential of different phosphorus (P) sources combined with varying dripline depths still requires further evaluation. MethodsWe established a 2-year field experiment with spring maize in 2021 and 2022 to determine the regulatory effects of three P sources [P1, monoammonium phosphate (MAP); P2, ammonium polyphosphate (APP); and P0, no P] and three dripline depths (D0, surface drip irrigation, 0 cm; D15, subsurface at 15 cm depth; and D30, subsurface at 30 cm depth) on the soil NO3-N, NH4-N and Olsen-P distribution, root distribution, nitrogen (N) fertilizer partial factor productivity (PFPN) and P use efficiency (PUE), and grain yield. ResultsWe found a significant coupling effect between the P source and dripline depth, both of which significantly impacted soil nutrients and root distribution, grain yield, PFPN, and PUE. In P1D15 and P2D15, the highest soil NO3-N and Olsen-P contents were observed at soil depths of 0–30 and 10–20 cm and at 0–30 and 10–30 cm, respectively. Similarly, in P1D30 and P2D30, which were 20–40 and 20–40 cm, and 20–40 and 30–60 cm, respectively. Compared to the other treatments, P2D15 and P1D30 exhibited considerable increases in root length density at the 30–60 cm soil depth of 37∼52 % and 28∼58 %, respectively. Regardless of the dripline depth, P0 resulted in the lowest yield during both growing seasons. P1D30 and P2D15 were found to be the optimal combinations for achieving higher grain yield, PFPN, and PUE, as they were able to achieve a high degree of coordination between soil available N and Olsen-P, as well as root distribution. ConclusionsThe recommended approach for optimizing nutrient and root spatial distributions under subsurface drip irrigation systems involves the use of poly-P fertilizer (APP) in conjunction with shallow dripline depth and ortho-P fertilizer (MAP) paired with deep dripline depth, which provides valuable guidance for co-fertigation practices involving N and P fertilizers.

Microbial interactions modify saffron traits selectively and modulate immunity through adaptive antioxidative strategy: Organic cultivation modules should be trait and crop-specific

Saffron (Crocus sativus L.) is a high-value, low-volume niche cash crop that has the unique ability to synthesize apocarotenoids. Since different biofertilizers are advocated for promoting plant health, we aimed to evaluate the interactions of commercially available microbial inoculants with this unique hysteranthous plant species. We studied the interactive effect of microbial inoculants on agronomical, physiological and biochemical aspects of Crocus growth, corm multiplication and apo-carotenoid biosynthesis. Significant differences in nutrient mobilization potential, induced systemic resistance, plant growth, corm, and stigma yield/quality were detected between the different biofertilizer combinations. The arbuscular mycorrhizal fungi (AMF) + phosphate-solubilizing bacteria (PSB) + potassium-solubilizing bacteria (KSB) combination was the most suitable for enhancing shoot biomass, root depth, and root biomass. Additionally, the average number of flowers per corm, stigma yield, and corm yield were greatest for the same combination. The highest multiplication rate of mother corms and a small corm index were recorded for plants inoculated with Azospirillum + PSB + KSB. Although Azospirillum caused maximum multiplication, the percentage of smaller daughter corms was greater, while the replacement of Azospirillum with AMF resulted in maximum percentage of larger corms. Plant health improved through AMF-mediated microbial interactions, which induced systemic resistance via enzymatic and nonenzymatic mechanisms and increased the uptake of P, K, Cu, Fe, Mn, and Zn. The interrelationship between plant and microbial consortium was complex, causing trait-specific qualitative and quantitative impacts on saffron attributes. Microbial inoculants increased nutrient uptake by saffron plants and triggered biochemical defence response by causing mild stress, making the plant more growth-responsive and better equipped for defence. Microbial interaction increased saffron yield and quality by favourably modulating plant metabolism, majorly overlapping with plant protection mechanisms. However, plant-microbial combinations in an organic production module are trait-specific and should be chosen carefully.

Removal of nitrate and phosphate by aquatic plants during aquarium‐based ornamental fish production

AbstractObjectiveThe rising demand for ornamental fish and plants in aquariums is met through industrial production. However, higher production densities may negatively impact water quality (such as ammonia, nitrate, nitrite, and dissolved oxygen levels), thus impacting production. This can be mitigated by utilizing specific aquatic plants to promote sustainable ornamental fish production. This study aimed to determine how the water quality in ornamental fish tanks can be improved using two floating aquarium plant species: Najas grass Najas guadalupensis and Java moss Taxiphyllum barbieri.MethodsThe efficiency of nitrate and phosphate filtration by the two plant species was determined in aquariums containing Endler Guppies Poecilia wingei. The duration of the study was 4 weeks, and the water quality parameters were measured weekly. The growth rates of the two plants were measured at the beginning and end of the study period.ResultNajas grass effectively maintained lower nitrate and phosphate levels while showing robust growth. By week 4, nitrate levels in control tanks rose to 33.75 and 35.00 mg/L in the two independent experiments, while nitrate in tanks with Najas grass only reached 8.75 and 11.50 mg/L. Phosphate levels in control tanks increased to 2.42 and 2.40 mg/L compared to 1.075 and 1.05 mg/L in tanks with Najas grass. In single‐species tanks, Najas grass showed a 1.6‐fold biomass increase, while Java moss showed a 1.2‐fold increase. In tanks with both species, Najas grass biomass increased significantly, whereas Java moss biomass decreased.ConclusionThe superior competitive ability of Najas grass (allelopathy and increased nutrient uptake) underlies the findings of this study and indicates that this species is a better option for maintaining low levels of nitrate and phosphate in aquarium water. This finding can contribute to creating a cleaner and healthier environment for fish species involved in industrial ornamental fish production and trade.

Novel biostimulant bacterial exopolysaccharides production via solid-state fermentation as a valorisation strategy for agri-food waste.

Bacterial exopolysaccharides (EPS) are extracellular polymer-based substances recently defined as potential plant biostimulants, as they can increase nutrient uptake, water retention, and resistance to abiotic stress. As sugar-based substances, the bacteria producing them need to grow in a sugar-rich substrate. Hence, some agri-food by-products could be used as suitable carbon sources for EPS production as a cost-effective and more sustainable alternative to conventional substrates. Thus, this study aimed to produce EPS from specific bacterial strains through solid-state fermentation (SSF) using agri-food waste as a low-cost substrate. Six residues and five bacterial strains were tested in a lab-scale SSF system. From the assessed substrate-strain combinations, Burkholderia cepacia with ginger juice waste (GJW) resulted in the most promising considering several process parameters (EPS production, cumulative oxygen consumption, biomass growth, reducing sugars consumption). Also, dynamic monitoring of the system allowed for establishing 5days as a suitable fermentation time. Then, using response surface methodology (Box-Behnken design), the process was optimised based on airflow rate (AF), inoculum size (IS), and micronutrient concentration (MN). In this stage, the best conditions found were at 0.049 (± 0.014) L h-1 per gram of dry matter (DM) for AF, 8.4 (± 0.9) E + 09CFUg-1 DM for IS, and 0.07 (± 0.01) mL g-1 DM for MN, reaching up to 71.1 (± 3.2) mg crude EPS g-1 DM. Results show the potential of this approach to provide a new perspective on the value chain for the agri-food industry by introducing it to a circular economy framework.

The role of mycorrhizal fungi in enhancing fertiliser efficiency in agriculture

The study was conducted to evaluate the impact of mycorrhizal fungi on the yield, biomass and quality of cereals (wheat and maize) in the South of Ukraine. For the experiment, control and experimental plots were selected where mycorrhizal fungi were used to improve plant nutrient uptake. The research process included detailed measurements of yields, biomass and uptake of nutrients such as phosphorus, nitrogen and potassium at different stages of the growing season. The results showed that the use of mycorrhizal fungi increased wheat yields by 15% and corn yields by 18% in the experimental plots compared to the control plots, which was achieved through increased nutrient uptake from deeper soil layers. Wheat biomass increased by 12% and corn biomass by 14%, indicating a positive impact of mycorrhiza on plant development. Phosphorus uptake at a depth of 20-30 cm increased by 50%, which contributed to better root development and the supply of available elements to plants. In addition, we recorded a 7% increase in protein content in wheat grain and a 9% increase in corn, which indicates an improvement in the nutritional and feed value of the products. The analysis also showed a 4% increase in the oil content of corn grain, which increases its economic value. Another important result was a 15% reduction in mineral fertiliser costs due to improved nutrient use efficiency, which reduces the need for additional fertiliser. The results confirm that the use of mycorrhizal fungi is an effective method for increasing yields, product quality and economic efficiency of agricultural production

Unveiling the efficacy of Bacillus faecalis and composted biochar in alleviating arsenic toxicity in maize

Arsenic (As) contamination is a major environmental pollutant that adversely affects plant physiological processes and can hinder nutrients and water availability. Such conditions ultimately resulted in stunted growth, low yield, and poor plant health. Using rhizobacteria and composted biochar (ECB) can effectively overcome this problem. Rhizobacteria have the potential to enhance plant growth by promoting nutrient uptake, producing growth hormones, and suppressing diseases. Composted biochar can enhance plant growth by improving aeration, water retention, and nutrient cycling. Its porous structure supports beneficial microorganisms, increasing nutrient uptake and resilience to stressors, ultimately boosting yields while sequestering carbon. Therefore, the current study was conducted to investigate the combined effect of previously isolated Bacillus faecalis (B. faecalis) and ECB as amendments on maize cultivated under different As levels (0, 300, 600 mg As/kg soil). Four treatments (control, 0.5% composted biochar (0.5ECB), B. faecalis, and 0.5ECB + B. faecalis) were applied in four replications following a completely randomized design. Results showed that the 0.5ECB + B. faecalis treatment led to a significant rise in maize plant height (~ 99%), shoot length (~ 55%), root length (~ 82%), shoot fresh (~ 87%), and shoot dry weight (~ 96%), root fresh (~ 97%), and dry weight (~ 91%) over the control under 600As stress. There was a notable increase in maize chlorophyll a (~ 99%), chlorophyll b (~ 81%), total chlorophyll (~ 94%), and shoot N, P, and K concentration compared to control under As stress, also showing the potential of 0.5ECB + B. faecalis treatment. Consequently, the findings suggest that applying 0.5ECB + B. faecalis is a strategy for alleviating As stress in maize plants.

Intensifying Cadmium remediation: the impact of synergy between Crambe abyssinica and plant growth-promoting microorganisms

Cd, a toxic metal, is naturally found in the environment and is exacerbated by human activities such as mining, agriculture, and industrial processes. Its contamination in soils poses serious risks to human health and ecosystems, prompting the need for effective remediation strategies. This study focuses on the use of Crambe abyssinica, an oilseed plant known for its tolerance to adverse environmental conditions, including Cd contamination, for phytoremediation of contaminated soils, associated with bioremediation through plant growth-promoting microorganisms. The study involved growing Crambe in vitro. Methods included seed asepsis, substrate contamination with various Cd concentrations, and inoculation with beneficial microorganisms such as Bradyrhizobium japonicum, Bacillus subtilis along with Bacillus megaterium, Azospirillum. brasilense, Pseudomonas fluorescens, and Trichoderma harzianum. Data such as plant length and root area were measured, and the nutrient and Cd content in the plants were assessed. Results indicated that inoculation with microorganisms significantly enhanced the nutrient content in Crambe plants, even under different Cd concentrations. Notably, A. brasilense and P. fluorescens were particularly effective, not only increasing nutrient uptake but also enhancing Cd accumulation in the plants, which is crucial for phytoremediation. The presence of these microorganisms also led to a significant reduction in the Cd concentration in the substrate, showcasing their potential in bioaugmentation. The study highlights the efficacy of using Crambe abyssinica in conjunction with specific microorganisms for the remediation of Cd-contaminated soils. The synergistic effects of these plant-microorganism interactions not only promote plant growth and health but also enhance the phytoextraction of Cd, offering a sustainable solution to soil contamination. Future research should focus on optimizing these interactions and exploring their applications in larger-scale environmental remediation projects.

Arbuscular mycorrhizal fungi regulate amino acid metabolism, phytohormones and glycolysis pathway to promote the growth of Suaeda salsa under combined Cd and NaCl stresses

The use of halophytes in conjunction with arbuscular mycorrhizal (AM) fungi has been found to enhance the removal efficacy of heavy metals and salts in heavy metals contaminated saline soil. The mechanisms of AM fungi on promoting halophyte growth and regulating metabolism remain unclear. In this study, combinations of 0 g kg−1 NaCl and 3 mg kg−1 Cd (S0Cd3), 6 g kg−1 NaCl and 3 mg kg−1 Cd (S6Cd3), and 12 g kg−1 NaCl and 3 mg kg−1 Cd (S12Cd3) were employed to explore the impact of Funneliformis mosseae on the growth and metabolism of Suaeda salsa. The results showed that AM fungi increased the biomass and the P, K+, Ca2+, and Mg2+ accumulations, reduced the Cd and Na+ concentrations in S0Cd3 and S6Cd3, and increased the Cd concentrations in S12Cd3. AM fungi inoculation reduced the Cd and Na+ transfer factors and increased the Cd and Na+ accumulations in S6Cd3. The metabolomics of S6Cd3 showed that AM fungi upregulated the expression of 5-hydroxy-L-tryptophan and 3-indoleacid acid in tryptophan metabolism, potentially acting as crucial antioxidants enabling plants to actively cope with abiotic stresses. AM fungi upregulated the expression of arbutin in glycolysis process, enhancing the plants’ osmoregulation capacity. AM fungi upregulated the expression of 2-hydroxycinnamic acid in phenylalanine metabolism and dopaquinone in tyrosine metabolism. These two metabolites help effectively remove reactive oxygen species. Correspondingly, AM fungi decreased MDA content and increased soluble sugar content. These results indicate that AM fungi improve the stress resistance of S. salsa by increasing nutrient uptake and regulating physiological and metabolic changes.

Plant-microbe Interactions and their Potential Application in Improving Disease Resistance in Vegetable Crops

Microorganisms have a substantial impact on the environment and have been observed to either immunize or infect organisms from all kingdoms. Plants and microorganisms have undergone co-evolution and engage in interactions within their natural environment. Plant microbiota, often known as plant-associated microorganisms, are essential components of plant existence. Similar to other living systems, the plant body interacts with a range of living and non-living factors as it develops in an intricate environment. The plant microbiome can sustain disease suppression by providing essential tasks to their host, such as stress tolerance, vitality, and development. Plants and microorganisms have evolved molecular systems to mutually interact and derive advantages from their interaction. This symbiotic relationship is advantageous for both the microorganisms and the plants. Various pathways have been explored and are currently being utilized to achieve agricultural, environmental, and health benefits, based on this molecular interaction. Plant-associated microorganisms serve a vital role in the growth and development of plants. Microorganisms stimulate plant growth by directly increasing nutrient uptake and stimulating hormone production. The potential benefits of these mutually beneficial interactions between plants and microbes could be connected to develop microbial inoculants for application in agricultural biotechnology. In general, the utilization of microorganisms and the establishment of beneficial plant-microbe interactions offer promising and environmentally favourable approaches for sustainable and organic agriculture worldwide.

Enhancing Bok Choy growth through synergistic effects of hydrogel and different nitrogen fertilizer forms

The application of hydrogel to sandy soil has shown promise in enhancing crop production, offering alternative solutions to address the growing food demand. Here, we investigated the impact of hydrogel and different nitrogen (N) fertilizer forms (NH4+, NO3− and Urea) on Bok Choy (Brassica rapa var. chinensis) production through the evaluation of the plant growth parameters, photosynthesis, nutrient uptake, and soil physicochemical properties. Our findings reveal that the application of hydrogel significantly increased plant height (16.27 %), fresh weight (FW) (61.14 %), dry weight (DW) (65.69 %) weight, plant nutrient concentration, and uptake. Additionally, it improved photosynthetic parameters and induced alterations in soil physicochemical properties. The synergistic effects of hydrogel varied with different nitrogen forms, with NH4+–N fertilizer demonstrating the most efficiency in enhancing Bok Choy production (119.65 % FW) compared to control. Pearson correlation analysis established close associations between Bok Choy growth parameters, photosynthesis, nutrient accumulation, and soil physicochemical properties. Principal component analysis (PCA) underscored the significant influence of hydrogel and NH4+–N on various growth parameters in Bok Choy. The stimulated growth observed can be attributed to increased nutrient uptake, improved photosynthesis, and the maintenance of soil physicochemical properties. These findings carry significant implications for the practical application of hydrogel in the field, providing a valuable strategy to enhance nutrient use efficiency and crop production in sandy soil.

Functionality of arbuscular mycorrhizal fungi varies across different growth stages of maize under drought conditions

Physio-biochemical regulations governing crop growth period are pivotal for drought adaptation. Yet, the extent to which functionality of arbuscular mycorrhizal fungi (AM fungi) varies across different stages of maize growth under drought conditions remains uncertain. Therefore, periodic functionality of two different AM fungi i.e., Rhizophagus irregularis SUN16 and Glomus monosporum WUM11 were assessed at jointing, silking, and pre-harvest stages of maize subjected to different soil moisture gradients i.e., well-watered (80% SMC (soil moisture contents)), moderate drought (60% SMC), and severe drought (40% SMC). The study found that AM fungi significantly (p < 0.05) affected various morpho-physiological and biochemical parameters at different growth stages of maize under drought. As the plants matured, AM fungi enhanced root colonization, glomalin contents, and microbial biomass, leading to increased nutrient uptake and antioxidant activity. This boosted AM fungal activity ultimately improved photosynthetic efficiency, evident in increased photosynthetic pigments and photosynthesis. Notably, R. irregularis and G. monosporum improved water use efficiency and mycorrhizal dependency at critical growth stages like silking and pre-harvest, indicating their potential for drought resilience to stabilize yield. The principal component analysis highlighted distinct plant responses to drought across growth stages and AM fungi, emphasizing the importance of early-stage sensitivity. These findings underscore the potential of incorporating AM fungi into agricultural management practices to enhance physiological and biochemical responses, ultimately improving drought tolerance and yield in dryland maize cultivation.

Optimizing Agriculture: A Review of Chemical Priming in Crop Production

Agricultural productivity faces increasing challenges due to climate change, soil degradation, and the need for sustainable practices. Chemical priming, a technique involving the pre-treatment of seeds or plants with specific compounds, has emerged as a promising approach to enhance crop resilience, productivity, and stress tolerance. This review synthesizes current literature on the application of chemical priming in crop production, focusing on its mechanisms, effects on plant physiology, and its potential to optimize agricultural practices. Chemical priming operates through diverse mechanisms, including the induction of stress-responsive genes, enhancement of antioxidant activity, and modulation of hormone signaling pathways. These mechanisms result in improved germination rates, accelerated seedling growth, increased nutrient uptake, and enhanced tolerance to various abiotic and biotic stresses. Moreover, chemical priming has been shown to promote crop yield and quality under adverse environmental conditions, making it a valuable tool for sustainable agriculture. The effectiveness of chemical priming depends on various factors, such as the type of priming agent, concentration, timing of application, and the specific crop species. Furthermore, interactions with other agricultural practices, such as irrigation regimes and fertilization strategies, can influence its outcomes. Therefore, optimizing chemical priming protocols requires a comprehensive understanding of crop-specific responses and environmental factors. Despite its potential benefits, the widespread adoption of chemical priming in agriculture faces challenges related to cost-effectiveness, regulatory approval, and potential ecological impacts. Addressing these challenges requires further research to refine priming protocols, assess long-term effects on soil health and ecosystem functioning, and develop sustainable approaches for large-scale implementation.

English

The indiscriminate use of chemical fertilizers in agricultural tracts is a serious problem, contributing to soil microbial biomass carbon (SMBC) depletion. In this regard, the use of chemical fertilizers together with organic amendments is considered as a sustainable approach, which alters SMBC, thereby increasing nutrient availability in soil-plant ecosystems. The present study was thus conducted to examine the effects of various mixes of organic amendments both with and without chemical fertilizers (NPK) on SMBC and pea (Pisum sativum L.) growth. The following eight treatments were established: control, 100% farmyard manure (FYM), 100% compost, 50% compost + 50% FYM, 33% compost + 33% chemical fertilizers (NPK) + 33% FYM, 50% chemical fertilizers + 50% FYM, 50% compost + 50% NPK, and 100% NPK, each with three replications. Results showed that the combination of 33% compost + 33% NPK + 33% FYM (T5) had the most significant impact on plant height, number of leaves, and roots and shoots biomass. Furthermore, the combination of NPK, compost and FYM enhanced the soil organic matter and SMBC, contributing to the increased amounts of available NPK in the soil-plant systems. Based on the results, it has been concluded that 33% compost + 33% NPK, and 33% FYM improves pea productivity due to improved SMBC that contributed to increased nutrient uptake by plants. It has been suggested to the farmers that integrated nutrient management approaches must be adopted for maintaining SMBC and further sustainable crop production.

Bioprospecting of endophytic diazotrophic microbes in sustainable agriculture: Review and prospects

Endophytic diazotrophic bacteria play an important role in developing sustainable modern agriculture. Endophytic bacteria can increase plant growth and yield by exhibiting antibiosis against phytopathogens. Biological mechanisms of atmospheric nitrogen fixation, phosphate solubilization, production of phytohormones and inhibition of plant pathogens and pests promote plant growth avoiding the need for chemical fertilizers and control agents. This review evaluates the groups of different endophytic bacteria, their prospects and challenges for sustainable agriculture. Several new bacterial strains were protected as bioinoculants or biopesticides. Formulations containing endophytic bacteria mainly were intended for seed coating or spraying and acted directly in the control of pests and diseases, as well as in increasing resistance to environmental stress. In many cases, they performed well in promoting the growth of plants by producing hormones that regulate or increase nutrient uptake. Bioprospecting in the case of this review is a systematic overview of the rational approach in harnessing beneficial plant-associated microbes to ensure food security in the future.

Maize/soybean intercropping increases nutrient uptake, crop yield and modifies soil physio-chemical characteristics and enzymatic activities in the subtropical humid region based in Southwest China

Intercropping, a widely adopted agricultural practice worldwide, aims to increase crop yield, enhance plant nutrient uptake, and optimize the utilization of natural resources, contributing to sustainable farming practices on a global scale. However, the underlying changes in soil physio-chemical characteristics and enzymatic activities, which contribute to crop yield and nutrient uptake in the intercropping systems are largely unknown. Consequently, a two-year (2021–2022) field experiment was conducted on the maize/soybean intercropping practices with/without nitrogen (N) fertilization (i.e., N0; 0 N kg ha−1 and N1; 225 N kg ha−1 for maize and 100 N kg ha−1 for soybean ) to know whether such cropping system can improve the nutrients uptake and crop yields, soil physio-chemical characteristics, and soil enzymes, which ultimately results in enhanced crop yield. The results revealed that maize intercropping treatments (i.e., N0MI and N1MI) had higher crop yield, biomass dry matter, and 1000-grain weight of maize than mono-cropping treatments (i.e., N0MM, and N1MM). Nonetheless, these parameters were optimized in N1MI treatments in both years. For instance, N1MI produced the maximum grain yield (10,105 and 11,705 kg ha−1), biomass dry matter (13,893 and 14,093 kg ha−1), and 1000-grain weight (420 and 449 g) of maize in the year 2021 and 2022, respectively. Conversely, soybean intercropping treatments (i.e., N0SI and N1SI) reduced such yield parameters for soybean. Also, the land equivalent ratio (LER) and land equivalent ratio for N fertilization (LERN) values were always greater than 1, showing the intercropping system’s benefits in terms of yield and improved resource usage. Moreover, maize intercropping treatments (i.e., N0MI and N1MI) and soybean intercropping treatments (i.e., N0SI and N1SI) significantly (p < 0.05) enhanced the nutrient uptake (i.e., N, P, K, Ca, Fe, and Zn) of maize and soybean, however, these nutrients uptakes were more prominent in N1MI and N1SI treatments of maize and soybean, respectively in both years (2021 and 2022) compared with their mono-cropping treatments. Similarly, maize-soybean intercropping treatments (i.e., N0MSI and N1MSI) significantly (p < 0.05) improved the soil-based N, P, K, NH4, NO3, and soil organic matter, but, reduced the soil pH. Such maize-soybean intercropping treatments also improved the soil enzymatic activities such as protease (PT), sucrose (SC), acid phosphatase (AP), urease (UE), and catalase (CT) activities. This indicates that maize-soybean intercropping could potentially contribute to higher and better crop yield, enhanced plant nutrient uptake, improved soil nutrient pool, physio-chemical characteristics, and related soil enzymatic activities. Thus, preferring intercropping to mono-cropping could be a preferable choice for ecologically viable agricultural development.

Impact of Mechanized Crop Establishment Techniques on Growth, Yield, and Microbial Dynamics under Rice-Wheat Cropping System: A Review

The rice-wheat cropping system, predominant across the Indo-Gangetic plains, generates a substantial volume of crop residue, with an annual yield of 7-9 tonnes per hectare of rice residue. Effective management of this residue, whether in-situ or ex-situ, has become an urgent necessity. However, the economic feasibility of transporting residue beyond 20 km from the field is limited. Consequently, in-field residue management through the adoption of specialized machinery has emerged as an imperative solution. The narrow window between paddy harvesting and wheat sowing, compounded by labor scarcity during peak periods, underscores the need for mechanized crop establishment techniques. Machines such as happy seeders, super seeders, turbo seeders, spatial drills, and seed-cum-fertilizer drills are crucial tools in this regard. This paper examines the benefits of mechanized crop establishment techniques on wheat growth, productivity, and soil biological health within the rice-wheat cropping system. These techniques have revolutionized agricultural practices by significantly influencing growth dynamics, yield parameters, and microbial ecology. The adoption of precision seed drills and mechanized tillage equipment has transformed traditional farming methods, facilitating efficient seed placement, soil preparation, residue incorporation, and weed management. This has resulted in improved crop growth parameters, enhanced yield dynamics, better root development, increased nutrient uptake, and overall plant vigor. Furthermore, reduced soil disturbance and decreased weed pressure associated with mechanized operations have created a conducive environment for beneficial microbial communities to thrive. The integration of mechanized crop establishment techniques has a positive impact on both crop productivity and sustainability, highlighting their importance in modern agricultural practices within the rice-wheat cropping system of the Indo-Gangetic plains.

Root cutting on growth and yield of oil palm (Elaeis guenesis Jacq.)

Root cutting is speculated able to increase nutrient uptake by oil palm. The objective of this study was to investigate the effect of root trimming on the growth, flowering, and yield of oil palm. The research focused on oil palm plants aged five years old in the field. The experiment used a nested design with two key factors: root-cutting depth as the main plot and root-pruning intensity as the subplot. Results showed that root cutting at a depth of 0 to 20 cm from the soil surface followed by cutting intensities of 50% and 75% enhanced plant height at 0, 3, and 9 months after treatment. The treatments did not affect other variables including flowering and yield of oil palm trees. Keywords: bunch weight; cutting intensity; root trimming; sex ratio

Temperature optima of a natural diatom population increases as global warming proceeds

AbstractStudies in laboratory-based experimental evolution have demonstrated that phytoplankton species can rapidly adapt to higher temperatures. However, adaptation processes and their pace remain largely unknown under natural conditions. Here, by comparing resurrected Skeletonema marinoi strains from the Baltic Sea during the past 60 years, we show that modern S. marinoi have increased their temperature optima by 1 °C. With the increasing ability to grow in higher temperatures, growth rates in cold water decreased. Modern S. marinoi modified their valve:girdle ratio under warmer temperatures, which probably increases nutrient uptake ability. This was supported by the upregulation of several genes related to nitrate metabolism in modern strains grown under high temperatures. Our approach using resurrected strains demonstrates the adaptation potential of naturally occurring marine diatoms to increasing temperatures as global warming proceeds and exemplifies a realistic pace of evolution, which is an order of magnitude slower than estimated by experimental evolution.

Improved bacterial composition and co-occurrence patterns of rhizosphere increased nutrient uptake and grain yield through cultivars mixtures in maize

Crop diversification contributes to agricultural productivity and resources efficient utilization. However, whether cultivar mixtures in maize affects soil bacterial community, nutrient uptake, plant growth and yield remains unknown. A two-year lysimetric experiment was conducted using two maize cultivars (LY16 and JS501) with different root system architectures planted in monoculture or in mixture under normal fertilization (NF), reduced fertilization (RF) or no addition of fertilizer (CK) and was assessed at the silking stages. Cultivar mixtures and monoculture of LY16 had higher shoot biomass, nutrient uptake and total root length at silking stage, and grain yield than monoculture of JS501 under NF and RF conditions. Under NF and RF conditions, cultivar mixtures and monoculture of LY16 led to an increase in bacterial diversity, significant changes in community structure, and a high abundance of Bacteroidia and biomarkers of Chitinophagaceae and Saprospiraceae (Bacteroidia). Cultivar mixtures showed specific responses from modules of the rhizosphere bacterial community co-occurrence network, and the relative abundance of keystone taxa of cultivar mixtures was higher than that of monoculture of JS501. The keystone taxa had a broad and significant positive correlation with plant nutrient accumulation and grain yield. Cultivar mixtures showed similar assembly processes of Bacteroidia with monoculture of LY16, and the increased abundance of Chitinophagaceae may lead to a healthy rhizosphere bacterial community. Overall, our findings indicate that cultivar mixtures significantly affects the assembly and composition of the rhizosphere bacterial community, and thus benefits plant nutrient acquisition and plant growth. These findings could deepen our understanding of the facilitating effect of rhizosphere functional microbial community (e.g. plant nutrition uptake or immunity)of cultivar mixtures.