Root Dry Weight Research Articles

Morphological, biochemical and genotoxic effects of non-ionizing radiation at 1800MHz and 2400MHz frequencies in Allium cepa L.

The frequent use of electronic devices in daily lives, predominantly reliant on non-ionizing radiation, has increased the prevalence of electromagnetic radiation (EMR) in natural environment. In light of this, effects of EMR at frequencies of 1800MHz and 2400MHz characterized by a power of 10.0 dBm (0.01 W), across varying exposure durations of 1h/day, 2h/day, 4h/day, 6h/day, and 8h/day for 7days, in Allium cepa L. were studied. The effects of the treatment on the morphological features (root length, fresh weight, and dry weight of roots) and biochemical characteristics (protein content and antioxidative enzymes, namely, ascorbate peroxidase (APX), glutathione reductase (GR), superoxide dismutase (SOD), glutathione-S-transferase (GST), guaiacol peroxidase (POD), catalase (CAT), and dehydroascorbate (DHAR)) were studied in roots and bulbs of Allium cepa L. Further genotoxicity for different exposure periods at both frequencies was also conducted. Prolonged exposure to electromagnetic radiation (EMR) at both frequencies was found to reduce root length, fresh weight, and dry weight of plant. Furthermore, significant effects were observed on protein content, indicating a reduction with prolonged exposure duration. Investigation into the activities of antioxidative enzymes such as APX, GR, GST, DHAR, CAT, SOD, and POD at a frequency of 1800MHz and 2400MHz in roots and bulbs demonstrated a significant enhancement in enzyme activity during 6h/day and 8h/day exposure periods. Additional investigation during genotoxicity studies demonstrated the induction of chromosomal aberrations in the root tip cells of the Allium cepa L. plant test system. The current study revealed the initiation of oxidative stress and genotoxicity resulting from long-term exposure to electromagnetic radiation in the studied plant test systems.

Bacterial endophyte Pseudomonas mosselii PR5 improves growth, nutrient accumulation, and yield of rice (Oryza sativa L.) through various application methods

BackgroundPseudomonas spp. have drawn considerable attention due to their rhizospheric abundance and exceptional plant growth-promoting attributes. However, more research is needed on the optimal application methods of Pseudomonas mosselii for rice growth, nutrient accumulation, and yield improvement. This research explored the application of the endophytic bacterium P. mosselii PR5 on rice cultivar BRRI dhan29 with four treatments: control, seedling priming, root drenching, and bacterial cell-free culture (CFC) foliar application.ResultsPR5 led to better rice growth, improved nutrient acquisition, and higher yields compared to the control, regardless of the application method used. The highest results in fresh weight of root (146.93 g/pot), shoot (758.98 g/pot), and flag leaf (7.88 g/pot), dry weight of root (42.16 g/pot), shoot (97.32 g/pot), and flag leaf (2.69 g/pot), and grains/panicle (224.67), were obtained from seedling priming treatment, whereas root drenching resulted in maximum plant height (105.67 cm), root length (49.0 cm), tillers/pot (23.7), and panicles/pot (17.67). In all three application methods, rice grain yield per pot was higher in PR5 inoculated treatments, compared to the control. The amount of P, Mg and Zn in the shoot and N, P, Ca, Mg and Si content in the flag leaf was significantly increased along with effective suppression of naturally occurring blast disease in bacterial CFC foliar application, validated by multivariate analysis.ConclusionOur results indicated that rice seedlings priming with PR5 improved rice growth, yield and nutrient uptake, whereas CFC foliar application significantly increased the concentration of most nutrients in the rice plant and suppressed the naturally occurring rice blast disease. This research highlights the significant potential of P. mosselii PR5 in enhancing rice growth, yield, and nutrient uptake, particularly through seedling priming and CFC foliar application methods.

Phosphorus Supply Under Micro-Nano Bubble Water Drip Irrigation Enhances Maize Yield and Phosphorus Use Efficiency.

This study aimed to explore the combined effects of micro-nano bubble water drip irrigation and different phosphorus (P) application rates (P0: 0 kg·hm-2; P1: 86 kg·hm-2; P2: 172 kg·hm-2; P3: 258 kg·hm-2) on maize growth, soil phosphorus dynamics, and phosphorus use efficiency to optimize irrigation and P fertilizer use efficiency. Through a field column experiment, the impact of micro-nano bubble water drip irrigation on maize plant height, stem diameter, leaf SPAD values, biomass, and yield was evaluated. The results showed that (1) irrigation methods significantly affected maize growth indicators such as plant height, stem diameter, and root dry weight. Micro-nano bubble water drip irrigation consistently promoted growth during all growth stages, especially under higher P application. (2) P application significantly increased the dry weight and P concentration in maize roots, stems, leaves, ears, and grains. Under micro-nano bubble water drip irrigation, the P concentrations in roots and grains increased by 59.28% to 92.59%. (3) Micro-nano bubble water drip irrigation significantly enhanced P uptake efficiency, partial factor productivity of P, and agronomic P use efficiency. Particularly under P1 and P2 treatments, the increases were 134.91% and 45.42%, respectively. Although the effect on apparent P recovery efficiency was relatively small, micro-nano bubble water drip irrigation still improved P utilization under moderate P levels. (4) Structural equation modeling indicated that P supply under micro-nano bubble water drip irrigation primarily regulated alkaline protease and alkaline phosphatase, enhancing soil P availability, which in turn promoted maize P accumulation and increased yield. In conclusion, this study demonstrated that the combination of micro-nano bubble water drip irrigation and appropriate P application can effectively promote maize growth and nutrient utilization, providing a theoretical basis for optimizing irrigation and fertilization strategies in maize production.

Selected Actinomycetes as Potential Biostimulant of Eggplant (Solanum melongena L) in Mali

Aims: This study aims to formulate at least one efficient biostimulant based on actinomycetes that promotes good eggplant growth in Mali. Study Design: The experimental design was a completely randomized block design with three replications and four treatments randomly distributed. The treatments were three Actinomycete strains (Act, S1 and St1) and a non inoculated control and the mode of application (inoculation or spraying) of these treatments were considered as blocking factor. Place and Duration of Study: The trials were conducted in Bamako, in the Greenhouse of the LaboREM-Biotech situated on the colline of Badalabougou. Methodology: Eggplant seeds inoculated or not with Actinomyces sp. Ts1, Actinomyces sp. S1 and Actinomyces sp. Act; were randomly sown in plastic pots filled with approximately 2.50 kg of air-dried soil. The first block sown with coated seeds and the second with non-inoculated seeds and seedlings from them pulverized. Leaf length, leaf area, leaf diameter, leaf area, leaf fresh weight, leaf dry weight, root fresh weight, root dry weight, plant height and root length were determined. Results: Eggplant seed inoculated with all the tested Actinomycetes strains had significantly enhanced leaf length, leaf diameter, leaf area, leaves fresh weight. The highest results were obtained with the strain Act, followed by strain St1. Sprayed treatment improved eggplant leaf length, leaf diameter, leaf area, leaves fresh weight, leaves dry weight, root fresh weight, root dry weight; compared to the coated treatment Conclusion: Field application of actinomyctes may reduce production cost, by increasing eggplant growth and fruit yield while reducing production cost. The present work showed that Act and Ts1 using spray method were best suited for eggplant. Actinomyces sp. Act produced the highest leaf length, leaf diameter, leaf area, leaves fresh weight. Therefore, Actinomyces sp. Act is suggested as bioinoculant for eggplant.

Performance of Mango (Mangifera indica L.) Grafts cv. Alphonso Raised in Soilless Media in Various Types of Containers

In world, Konkan region is famous for cultivation of king of mangoes ‘Alphonso’. Along with production, export and processing of Alphonso, this coastal belt is famous for supply of best quality planting material producing more than one crore grafts every year. Mango grafts are raised in polybag of size 6” x 8” weighing 1.5 kg available for sale after 9 months. In recent years, it was reported by farmers that polybags produced seedlings having spiralled and deformed root system reduce outplanting survival and performance of mango grafts within few years after plantation. Use of discarded plastic water bottles as root trainer could be a feasible alternative for seedling propagation. An experiment entitled “Performance of mango (Mangifera indica L.) grafts cv. Alphonso raised in soilless media in various types of containers” was carried out during the period 2023 at Department of Fruit Science, College of Horticulture, Dapoli, Dist. Ratnagiri in randomized block design with four replications and six treatments viz. T1-Nursery bag (6×8 Inch), T2-Green bottle (2.25 lit), T3-Transparent bottle (2.25 lit), T4-Transparent bottle (1 lit), T5-Black root trainer (0.5 lit), T6-Nursery bag (6×8 Inch) (with soil:FYM 3:1 as control). Mango grafts raised in transparent bottle (2.25 lit) with media cocopeat + leaf manure + vermicompost (1:1:2) recorded the highest sprouting (98.13 %), height (29.33 cm), girth (12.32 mm), leaf area (523.48 cm2), root length (25.50 cm), dry root weight (11.00 g) and survival (98.13 %) at 180 days after grafting with 1.84 benefit: cost.

Impact of supplemental irrigation and organic manure on growth and yield performance of rice variety BRRI dhan103 under terminal drought condition in Aman season

BRRI dhan103 is a transplanting Aman (T. Aman) rice variety that demands sufficient organic manure and supplemental irrigation to ensure successful production. Seven treatments, viz., T1= rainfed control; T2= one supplemental irrigation at 80 days after transplanting (DAT); T3= two supplemental irrigations at 70 and 80 DAT; T4= additional 5 t ha-1 poultry compost under rainfed condition; T5= additional 10 t ha-1 poultry compost under rainfed condition; T6= additional 2.5 t ha-1 biochar under rainfed condition; and T7= additional 5 t ha-1 biochar under rainfed condition, were evaluated against BRRI dhan103 to assess the impact of supplemental irrigation and manuring under terminal drought conditions. It was revealed that supplemental irrigation and manuring significantly improved all growth parameters and yield attributes compared to the rainfed control. Notably, T5 treatment provided its greatest performance statistically in respect of SPAD value (36.13), root dry weight (12.43 g), number of tillers hill-1 (13.22), panicle length (28.87 cm), panicles hill-1 at harvest (9.13), total spikelet (194.53), spikelet panicle-1 (197.63), filled spikelet panicle-1 (197.63), thousand grain weight (33.78 g), grain weight panicle-1 (28.70 g), grain yield hill-1 (31.97 g), and above-ground biological yield (3043.35 g m-2). The highest tiller hill-1 at harvest (9.53) was achieved when an additional 10 t ha-1 of poultry compost was applied under rainfed conditions. This study suggested that additional 10 t ha-1 poultry compost under rainfed conditions performed best to enhance the growth and yield of BRRI dhan103.

Response of host Indian Musa germplasm against artificially induced root lesion nematodes (Pratylenchus coffeae)

Under greenhouse condition, the host response of fifty-nine banana genotypes (Musa spp.) from the Eumusa section to the root-lesion nematode (Pratylenchus coffeae) was assessed. In a factorial completely randomized design (FCRD) with five replications, healthy banana suckers of the diploid and triploid accessions were planted in cement pots. Uninoculated controls were included in the experiment as comparison to study the sensitivity of the genotypes. Two varieties (Pisang Lilin and Nendran) with known reaction to lesion nematode were also included as reference clones because of their resistance and susceptibility to P. coffeae. Banana accessions maintained in the pots were inoculated with infective juveniles of root-lesion nematode, P. coffeae at 45 days after planting at the rate of 400 nematodes/pot. Ninety days after inoculation, the plants were harvested to observe the response of the different banana genotypes to P. coffeae. Data were recorded on plant growth (plant height, girth at the base, number of standing leaves, number of roots and weight of the root system), root damage assessment (percentage of infected roots and percentage necrosis) and nematode reproduction. When inoculated with nematodes, the reduction in plant growth attributes was relatively higher in genotypes that were susceptible. The reduction in growth characters viz., plants height, number of roots and root fresh weight were maximum in the diploid genotypes Manguthamng (26.80, 27.2, 33.0 %) and Manohar (25.70, 29.2, 35.2 %) and in the triploid genotypes Kaali, Rajthali, Digjowa, Saapkal, Cheenichampa, Dasaman, Borchampa, Jahaji, Manjahaji, Barjahaji and Sabri when inoculated with Pratylenchus coffeae. Even after nematode inoculation, root investigations showed that resistant and tolerant genotypes had greater numbers of roots as well as high fresh and dry weight of roots. Root and soil population of nematodes assessed at 90 days after inoculation indicated very high population buildup of Pratylenchus coffeae (>28) in diploids Manguthamng and Nendrapadathi and in triploids Jahaji, Manjahaji, Saapkal, Borchampa, Therahaw-1163 and 1164, Ankur-I and Bersain. The rate was the lowest (<9) in the diploid genotypes Kanai Bansi, Kechulepa, M.balbisiana, Athiakol, Bhimkol and Aittakola and in the triploids Karthobiumtham and Ankur-II. The results of the experiment showed that the diploids Musa balbisiana (BB), Aittakola (BB), Bhimkol (BB), Kechulepa (BB), Kanai Bansi (AA) and Athiakol (BB) and the triploid genotypes Kachkel (ABB), Karthobiumtham (ABB) and Ankur-II (ABB) were resistant to Pratylenchus coffeae.

DAMPAK PERTUMBUHAN BIBIT KELAPA SAWIT (Elaeis guineensis Jacq.) TERHADAP PEMBERIAN PUPUK ANORGANIK DAN KOMPOS LIMBAH LUMPUR IPAL PABRIK KARET DI PEMBIBITAN UTAMA

Jambi Province was one of the centers of oil palm plantations in Indonesia and there was another problem likes the age of the plants which had getting older and its worried caused decrease in production. Therefore, its was necessary to replanted oil palm for produced high quality seeds. The purpose of study was to determine the response of application and discover the best single dose of inorganic fertilizer and WWTP sludge compost in the growth of oil palm seedlings in the main nursery. This research was conducted at Teaching and Research Farm, UNJA (September-November 2022). This study used Completely Randomized Design with 5 treatments, (k0 = Urea, TSP, KCl recommended dose, k1 = Urea,TSP, KCl half recommended dose + 100 g WWTP sludge compost, k2 = Urea, TSP, KCl half recommended dose + 200 g WWTP sludge compost, k3 = Urea, TSP, KCl half recommended dose + 300 g WWTP sludge compost, k4 = Urea, TSP, KCl half recommended dose + 400 g WWTP sludge compost. The results showed the application of a single inorganic fertilizer and WWTP sludge compost was able to increased growth of seedling height, root dry weight and root volume. However, its has not been able to be increase of tuber diameter, the number of leaves, shoot dry weight and root crown ratio. Doses of Urea, TSP, KCl half recommended dose + 100 g WWTP sludge compost gived the best average growth of 6-month oil palm seedlings in the main nursery.

Exogenous Brassinolide Ameliorates the Adverse Effects of Gamma Radiation Stress and Increases the Survival Rate of Rice Seedlings by Modulating Antioxidant Metabolism.

Gamma irradiation-based mutant creation is one of the most important methods for rice plant mutagenesis breeding and molecular biology research. Although median lethal dose irradiation severely damages rice seedlings, applying brassinolide (BR) can increase the survival rate of irradiated seedlings. In this study, we investigated the effects of soaking seeds in solutions containing different BR concentrations (0.001, 0.01, 0.1, 1.0, and 5.0 μmol/L) and then spraying the resulting seedlings twice with 0.1 μmol/L BR. The combined BR treatments markedly decreased the superoxide anion (O2•-), hydrogen peroxide (H2O2), and malondialdehyde contents but increased the chlorophyll content. An appropriate BR treatment of gamma-irradiated samples substantially increased the activities of the antioxidant enzymes superoxide dismutase, peroxidase, and ascorbate peroxidase as well as the proline, ascorbic acid, and glutathione contents in rice seedling shoots. The BR treatment also promoted the growth of seedlings derived from irradiated seeds and increased the shoot and root fresh and dry weights. Most notably, soaking seeds in 0.01 or 0.1 μmol/L BR solutions and then spraying seedlings twice with 0.1 μmol/L BR significantly increased the final seedling survival rate and decreased mutant loss. The study results suggest that exogenous BR treatments can protect rice seedlings from gamma irradiation stress by enhancing antioxidant metabolism.

Low Nitrogen Availability in Organic Fertilizers Limited Organic Watermelon Transplant Growth

Fertilization guidelines for organic watermelon transplant production are rare. We investigated the effect of four commercial organic fertilizers and seven organic fertilizer blends, along with one conventional fertilizer (Peter’s Professional 20-20-20) on watermelon transplants. The four organic fertilizers were Nature Safe (fertilizer label: 7-7-7), Miracle-Gro (8-8-8), Dr. Earth fertilizer tea (4-4-4), and Drammatic (2-4-1). The seven blended organic fertilizers were created by supplementing Drammatic with nitrogen (N)-rich and/or potassium (K)-rich fertilizers to balance its N:phosphorus (P):K ratios. Watermelon ‘Jubilee’ was sown in organic substrate, and fertilizer treatments were applied weekly with a total of 0.4 g nitrogen/L substrate. Miracle-Gro and Drammatic had the highest N mineralization rate after 21 days and the highest inorganic N concentration, respectively, and resulted in the highest shoot dry weight among organic fertilizers. Miracle-Gro also resulted in the highest root dry weight. Dr. Earth fertilizer tea supplied the lowest N and P, and resulted in stunted transplants. Our results indicated that nitrate concentration was the most important factor influencing both shoot and root growth. Supplementing Drammatic with N-rich and/or K-rich fertilizers to balance its N:P:K ratio did not affect shoot and root dry weight. Combined, we concluded that nitrogen availability rather than nutrient balance is the key factor influencing watermelon transplant growth.

Uni- and Multivariate Analyses for the Characterization of Popcorn Inbred Lines for Drought Tolerance at Seedling and Vegetative Stages

Water deficit is the main limiting factor in rainfed agricultural production, negatively affecting germination and vegetative development. The objectives of this work were to characterize inbred lines for drought tolerance, to identify the most important root and shoot morphological traits for discriminating genotypes, to compare the efficiency of identifying contrasting inbred lines using uni- and multivariate methods, and to evaluate the effectiveness of identifying drought-tolerant genotypes at seedling and vegetative stages. We assessed 28 popcorn inbred lines and three maize single crosses, two drought-tolerant and one drought-sensitive. At the seedling stage, drought was induced on germitest paper moistened with polyethylene glycol 6000. At the vegetative stage, we applied water stress using lysimeters. We measured root and shoot morphological traits under water stress and no stress and processed the relative values. Uni- and multivariate methods, alone or in combination, were equally efficient for identifying contrasting inbred lines for drought tolerance. The confidence interval and Dunnett’s test worked very well when contrasting controls were included. Principal component analysis allowed to discriminate genotypes and identify the most important traits for discriminating them. At the seedling stage, inbred line 22-1824-2 was the most drought-tolerant and 22-1877-3 the most sensitive. At the vegetative stage, inbred lines 22-1920-1 and 22-1867-4 were the most tolerant and 22-1860-5 was the most sensitive. Root length, volume, dry weight, and surface area, as well as water content, were the most important traits for discriminating genotypes. Due to distinct tolerance mechanisms, drought tolerance should be assessed at both stages.

Isolation, Identification, and Application of Endophytic Fungi from Lavandula stoechas L.: Mitigating Salinity Stress in Hydroponic Winter Cereal Fodder

Soil and irrigation water salinity is a growing global problem affecting farmland, due to poor agricultural practices and climate change, leading to reduced crop yields. Given the limited amount of arable land and the need to boost production, hydroponic systems offer a viable solution. Additionally, endophytic fungi have been shown to mitigate salinity effects through symbiosis with plants. This study evaluated three endophytic fungi isolated from Lavandula stoechas L. in the grasslands of Extremadura (i.e., Diplodia corticola L11, Leptobacillium leptobactrum L15, and Cladosporium cladosporioides L16) for their ability to improve hydroponic forage production under saline conditions. In vitro experiments were conducted assessing plant growth promotion and fungal growth under salinity, followed by research evaluating the impact of fungal inoculation on hydroponic wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) forages irrigated with NaCl solutions (0, 100, and 200 mM). The results showed improved fungal growth and production of plant growth-promoting substances, which could explain the improved plant germination, shoot and root length, fresh and dry weight, and yield of inoculated plants growing under salinity. Plants inoculated with L15 or L16 showed the best performance overall. L15 demonstrated broader bioactivity in vitro, potentially explaining its superior performance in both wheat and barley growth. Conversely, L16 was more effective in barley, while L11 was beneficial in wheat but detrimental in barley. This study provides a preliminary exploration of the capabilities of these fungi and their optimization for hydroponic forage production.

Effects of salt stress on the fruit and yield quality of some selected tomato (<i>Lycopersicum esculentum</i> L.) varieties.

The growth, production, and nutritional characteristics of crops are impacted by abiotic factors such as salinity stress. The study aimed to assess the impact of salt stress on the fruit and yield characteristics of three distinct tomato cultivars, namely Rio, Dan syria, and UTC. Salt solutions with varying concentrations of NaCl were created by dissolving NaCl in deionized water. Four treatments were established, consisting of solutions with salt concentrations of 0g/L (control, without salt), 0.5g/L, 1.0g/L, and 1.5g/L. Each treatment was reproduced three times. The NaCl solutions were administered with a frequency of 7 days. The data in the study underwent Analysis of Variance (ANOVA). Rio outperformed the other varieties in terms of fruit quantity, fresh fruit weight, and fruit pericarp thickness under high salt stress, closely followed by UTC variety. The study also found that Dan syria performed better than the other varieties in terms of fresh and dry weight of shoot, as well as fresh weight of root, under mild and extreme salinity stress. However, Rio performed better than the other varieties in terms of dry weight of root under both mild and extreme salinity stress. The salt tolerance index of the Rio, UTC, and Dan Syria varieties under extreme salinity stress are 46.79%, 20.64%, and 34.70% respectively. This indicated that the Rio variety is the most salt-tolerant of the three types, with Dan Syria variety coming close.

Co-Inoculation of Phosphate-Solubilizing Bacteria and Rhizobia Increases Phosphorus Availability and Promotes the Development of Forage Legumes

Tropical grassland soils, especially those with alkaline properties, often exhibit limited phosphorus availability due to its precipitation in insoluble forms. Phosphate-solubilizing bacteria (PSB) and rhizobia have demonstrated their potential to enhance the availability of this nutrient and promote the growth of forage legumes. This study, conducted under controlled conditions in a mesh house, evaluated the effect of co-inoculation with PSB, including Micrococcus sp. Sfcm-14-01, Agrobacterium sp. Sfl-043-09, and Enterobacter sp. Sfcm-014-02 and Sfcm-054-06, along with rhizobia (Ensifer terangae R1-012-02 and Bradyrhizobium glycinis Rcm-025-01), under different levels of phosphorus fertilization on the legumes Leucaena leucocephala and Centrosema macrocarpum. The results indicate significant increases in various growth parameters, such as chlorophyll levels (SPAD), biomass (dry weight of roots and aerial parts) (mg), the foliar phosphorus concentration (ppm), and the concentration of available phosphorus in the soil, particularly under low-phosphorus fertilization conditions. The highest level of available phosphorus in the soil was achieved with 75% of the recommended fertilization dose, resulting in concentrations of 13.73 ppm for L. leucocephala and 7.69 ppm for C. macrocarpum, representing increases in phosphorus availability of 170.81% and 240.27%, respectively, compared with no fertilization or inoculation. These findings suggest that the co-inoculation of PSB and native rhizobia is a promising strategy to enhance the biomass productivity and mineral content of forage in tropical grazing systems, especially under phosphorus-limited conditions.

Exopolysaccharide-Producing Bacteria Regulate Soil Aggregates and Bacterial Communities to Inhibit the Uptake of Cadmium and Lead by Lettuce

The accumulation of heavy metals in the soil not only causes serious damage to the soil ecosystem, but also threatens human health through the food chain. Exopolysaccharides have the functions of adsorbing and chelating heavy metals and reducing their bioavailability in the soil. In our study, exopolysaccharide-producing bacteria with a high efficiency in adsorbing cadmium (Cd) and lead (Pb) were screened from heavy metal-contaminated farmland. Through pot experiments, the influence of functional strains on the size distribution, heavy metal content, and bacterial community structure of soil aggregates in lettuce was studied using high-throughput sequencing technology. The results show that 11 strains secreting exopolysaccharides were initially screened from heavy metal-contaminated soil. Among them, strain Z23 had a removal rate of 88.6% for Cd and 93.2% for Pb. The rate at which Cd was removed by strain Z39 was 92.3%, and the rate at which Pb was removed was 94.4%. Both strains belong to Bacillus sp. Strains Z23 and Z39 induced the formation of Fe2Pb(PO4)2, Cd2(PO4)2, and Pb2O3 in the solution. The pot experiments showed that strains Z23 and Z39 increased (19.1~23.9%) the dry weight and antioxidant enzyme activity of lettuce roots and leaves, while reducing (40.1~61.7%) the content of Cd and Pb. Strains Z23 and Z39 increased the proportion of microaggregates (<0.25 mm) and the content of exopolysaccharides in rhizosphere soil and reduced (38.4–59.7%) the contents of available Cd and Pb in microaggregates, thus inhibiting the absorption of heavy metals by lettuce. In addition, the exopolysaccharide content and the bacterial community associated with heavy metal resistance and nitrogen (N) cycling (Patescibacteria, Saccharimonadales, Microvirga, and Pseudomonas) in microaggregates were key factors affecting the available heavy metal content in soil. These results show that the exopolysaccharide-producing bacteria Z23 and Z39 reduced the absorption of Cd and Pb by lettuce tissues, thus providing strain resources for the safe utilization of soils that exceed heavy metal standards for farmland and for reducing the heavy metal content in vegetables.

Effects of Biochar and Cladophora glomerata on Wheat (Triticum aestivum L.) Growth and Rhizosphere Enzyme Activities

The positive effects of biochar on both soil quality and plant growth and also on plant growth of macroalgae have been reported in studies. Studies on biochar and macroalgae interaction are quite limited. This study was carried out according to randomized plot design in greenhouse conditions to determine the effects of biochar and Cladophora glomerata applications and interaction on the growth of wheat (Triticum aestivum L.) and some enzyme activities in the rhizosphere. Biochar and C. glomerata interaction increased wheat root (90%) and shoot dry weight (84.2%), root length (43.1%) and plant height (84.2%) compared to control. Biochar application increased alkaline phosphatase activity by 66.3%, while C. glomerata increased β-glucosidase activity by 49%. The interaction of both applications increased catalase activity by 62.1% compared to control. These findings confirm the potential of biochar and C. glomerata to improve wheat production by inducing growth.

Multispecies Trichoderma in Combination with Hydrolyzed Lignin Improve Tomato Growth, Yield, and Nutritional Quality of Fruits

The application of biological pesticides as alternatives to chemical phytosanitary products is a natural and innovative method to improve environmental protection and sustainable agricultural production. In this work, the compatibility between Trichoderma spp. and a commercial lignin extract was assessed in vitro and in vivo. The beneficial effects of lignin in combination with different Trichoderma consortia were evaluated in terms of improved growth and quantitative and qualitative tomato productivity. T. virens GV41 + T. asperellum + T. atroviride + lignin formulation was the most effective in growth promotion and increased root and stem dry weight compared to control (45.4 and 43.9%, respectively). This combination determined a 63% increase in tomato yield compared to the control, resulting in the best-performing treatment compared to each individual constituent. Consistent differences in terms of lycopene, GABA, ornithine, total, essential, and branched-chain amino acids were revealed in fruits from tomato plants treated with Trichoderma–lignin formulations (T. asperellum + T. virens GV41 + lignin) or with the microbial consortia (T. asperellum + T. virens GV41, T. atroviride + T. virens GV41). The developed bioformulations represent a sustainable biological strategy to increase yield and produce nutritional compound-enriched vegetables.

Accumulation of podophyllotoxin in the root culture of Hyptis suaveolens (L.) Poit: A potential natural lignan for clinically useful anticancer drugs

Podophyllotoxin (PTOX) is a natural antiviral, antirheumatic and anticancer molecule, but it is expensive to chemically synthesize. The present study aimed to evaluate growth and PTOX accumulation in root cultures of Hyptis suaveolens treated with different concentrations of auxins, vitamins and myo-inositol. Root cultures grown in liquid medium supplemented with different concentrations of indole-3-butyric acid (IBA), 1-naphthaleneacetic acid (NAA), vitamins and myo-inositol were used to measure biomass production and PTOX content. PTOX quantitation was performed via high-performance liquid chromatography with diode-array detection (HPLC-DAD) using a newly developed analytical method after successful validation. Root culture in MS medium supplemented with 1 mg L−1 IBA +0.5 mg L−1 NAA resulted in the highest root dry weight (248.76 mg) and the highest PTOX concentration in the roots (179.97 μg g−1 root). The roots cultured in liquid MS medium supplemented with 1 mg L−1 IBA +0.5 mg L−1 NAA presented the greatest increase in root biomass and PTOX content. This adequate balance of vitamin and myo-inositol supplementation in liquid MS culture medium increased the root dry weight and PTOX content.

ABA deficiency and its impact on ion and metabolite profiles in tomato roots under single and combined stress conditions

Abscisic acid (ABA) plays a crucial role in the stress response of plants. Although the impact of ABA on individual stresses has been extensively studied, there is less research on its role in plants grown under stress combination, such as salinity and high temperature. This study analyzes the response at the ionomic and metabolomic levels of tomato roots to ABA deficiency under single salinity or heat stress, as well as under the combination of both stresses, using ABA-deficient (flacca, flc) tomato plants. ABA was found to be crucial in ionic regulation, particularly for Na, K, Ca, and other ions such as Cu, Mn, Zn, Mo, and Fe. However, its influence depended on the type of stress applied, indicating the complexity of plant responses to these adverse environmental factors. In our study, phenylpropanoids, terpenoids, and nitrogenous compounds were the metabolites most affected by endogenous ABA concentration and environmental treatment. On the other hand, the application of exogenous ABA to flc mutants did not fully restore root dry weight, although it did cause significant changes at the ionomic and metabolomic levels. Salinity and heat applied in combination aggravated the vulnerability of flc mutants compared to single stresses, making the application of exogenous ABA more effective under single stresses than under the combined stresses. Finally, a correlation analysis between the ionome and metabolome revealed that the accumulation or deficiency of some ions (i.e., Na, Zn, and Fe) was correlated with the abundance of important metabolites related to amino acid biosynthesis and terpenoid metabolism, among others.

The effect of aeration and irrigation on the improvement of soil environment and yield in dryland maize.

The aim of this study was to examine the effect of long-term aerated seepage irrigation technology on soil fertility changes and maize yield under continuous maize cropping system in red loam soil, and to explain the mechanism of maize yield increase under this technology, which can provide theoretical basis for crop quality improvement and yield increase under aerated irrigation (AI) technology. Therefore, this research was conducted for four field seasons in 2020-2023 at the National Soil Quality Observation Experimental Station, Zhanjiang, China. Soil aeration, soil fertility, root growth, physiological traits, and yield indicators were evaluated by conventional underground drip irrigation (CK) and AI. Our results showed that AI treatment significantly improved soil aeration and soil fertility. Increases in soil oxygen content, soil respiration rate, soil bacterial biomass, and soil urease activity were observed, corresponding to increases from 3.08% to 21.34%, 1.90% to 24.71%, 26.37% to 0.09%, and 12.35% to 100.96%, respectively. The effect of AI on maize indicators increased year by year. Based on improvements in soil aeration and fertility, root length, root surface area, and root dry weight under AI treatment were enhanced by 15.56% to 53.79%, 30.13% to 62.31%, and 19.23% to 35.64% (p < 0.05) compared to the CK group. In addition, maize agronomic traits and physiological characteristics showed improved performance; in particular, over 1.16% to 14.42% increases were identified in maize yield by AI treatment. Further analysis using a structural equation model (SEM) demonstrated that the AI technology significantly promotes the improvement of root indicators by enhancing soil aeration and soil fertility. As a result, maize yield could be increased significantly and indirectly.