Bean Seedlings Research Articles

Wheat–faba bean intercropping can control Fusarium wilt in faba bean under F. commune and ferulic acid stress as revealed by histopathological analysis

Fusarium wilt, is an important soilborne disease restricting the cultivation of faba bean. Wheat–faba bean intercropping is one of the useful means to control Fusarium wilt in faba bean. In this study, we analyzed the histopathological effect of wheat–faba bean intercropping system on Fusarium wilt in faba bean under F. commune and ferulic acid stress. Faba bean was inoculated with F. commune. Various concentrations of ferulic acid were added to the inoculated plants to study the occurrence of Fusarium wilt, growth of faba bean seedlings, activity of cell-wall-degrading enzymes (CWDEs) produced by F. commune in stems, and structural changes in stem tissues under monocropping and intercropping systems. When ferulic acid was added to the faba bean plants inoculated with F. commune, wheat–faba bean intercropping significantly reduced the activity of CWDEs. Microstructure observation revealed that the xylem vessel was thickened, and xylem parenchymal tissue and vascular cambium produced gelatinous substance and tylose. Moreover, callose deposition was reduced in the sieve tube; death rate of vascular tissue, cortex tissue, and epidermis tissue was reduced, and faba bean biomass was observably increased. The combination of these factors reduced the occurrence of Fusarium wilt. Therefore, wheat–faba bean intercropping reduced the severity of Fusarium wilt in faba bean by decreasing the activities of CWDEs and increasing tissue structure integrity.

Application of Potassium Humate and Salicylic Acid to Mitigate Salinity Stress of Common Bean

In the current study, we investigated the effect of potassium humate (Kh) and salicylic acid (SA) in mitigating the salinity stress of common bean plants. Common bean seedlings were treated with 0.2 g/L SA as a foliar application and 0.3 g/L Kh as a soil application individually or in combination. After 7 days of germination, plants were treated with 50 mM NaCl and normal water as a control. Our results indicate that salt treatment reduced the plant growth (fresh and dry shoots and roots), leaf pigments (total chlorophyll and carotenoids), ascorbic acid (AA), glutathione (GSH), and potassium (K) contents. On the contrary, proline content; sodium (Na); hydrogen peroxide (H2O2); superoxide anion (O2•-); and antioxidant enzymes, including catalase (CAT), peroxidase (POX), and superoxide dismutase (SOD), were increased by saline stress. However, applying either individual Kh and SA or their combination stimulated seedling growth under salinity stress by increasing growth parameters, leaf pigment contents, AA, GSH, proline content, K content, and antioxidant enzymes compared with the control. Additionally, Na content, H2O2, and O2•- were reduced by all applications. The application of the Kh (0.3 g/L) + SA (0.2 g/L) combination was more effective than using the individual compounds. In conclusion, applications of Kh + SA can mitigate salt stress and improve the seedling growth of common bean.

Priming Bean Seedlings to Boost Natural Plant Defenses Against Common Bacterial Wilt: Salicylic Acid Responses to Chemical Primers (Part 1)

This greenhouse study evaluated the effects of two chemical inducers for priming kidney bean seedlings against a bacterial wilt disease. This study's central premise was that chlorine dioxide's oxidant properties would mimic the signaling properties of radical oxygen species, thereby initiating a cascade of molecular plant defenses, including the synthesis of salicylic acid (SA). This signaling agent then initiates a cascade of pre-defense activities to provide a more rapid and robust natural defense against pathogen attacks. This factorial study included two levels for a foliar chlorine dioxide treatment and two for a bacterial wilt inoculation treatment. The two plant response variables were free and conjugated salicylic acid levels sampled in leaf tissue over two collection dates. Half of the 96 plants were inoculated with a bacterial culture that causes common bean wilt disease. Leaf tissue was harvested 17 to 32 h and 960 h after the wilt inoculation to determine the temporal dynamics of SA due to chemical treatments. Also, PCR tests were used to verify wilt presence in the inoculated plants. Inoculation of the wilt disease did not affect free SA when leaf tissue was sampled from 17 to 32 h. after wilt inoculation. However, chlorine dioxide applied at 400 mg/l and sampled at 20 h after inoculation resulted in a 15-fold increase in free SA over the control. Also, chlorine dioxide applied at 400 mg/l with leaf tissue sampled at 26 h after inoculation resulted in a 33-fold increase in conjugate SA levels compared to the control plants. Leaf tissue sampled at 960 h after the inoculation showed no free SA differences among the chemical treatments. However, the inoculated plant had a 15.9-fold increase in free SA compared to the non-inoculated plants. The priming effect on kidney bean seedlings using a single chlorine dioxide foliage application temporarily increased free and conjugate SA. The free and conjugate SA levels for the non-inoculated plants returned to baseline levels when sampled at 960 h. These results indicate that primed plants elevate SA up to several weeks with a slow decline back to baseline levels. Stem injection of the bacterial wilt bypassed the immunity mechanisms present in leaves, which significantly increased the wilt injury levels. Stem injection negated much of the foliar defenses, which overshadowed the priming effects of the chemical treatments on plant immunity and foliar defenses. The second leaf sampling on newly formed leaves reveals elevated SA levels in the inoculated plants but not in the non-inoculated plants.

Modification of Xyloglucan Metabolism during a Decrease in Cell Wall Extensibility in 1-Aminocyclopropane-1-Carboxylic Acid-Treated Azuki Bean Epicotyls.

The exogenous application of ethylene or 1-aminocyclopropane-1-carboxylic acid (ACC), the biosynthetic precursor for ethylene, to plants decreases the capacity of the cell wall to extend, thereby inhibiting stem elongation. In this study, the mechanism by which the extensibility of cell walls decreases in ACC-treated azuki bean epicotyls was studied. ACC decreased the total extensibility of cell walls, and such a decrease was due to the decrease in irreversible extensibility. ACC increased the molecular mass of xyloglucans but decreased the activity of xyloglucan-degrading enzymes. The expression of VaXTHS4, which only exhibits hydrolase activity toward xyloglucans, was downregulated by ACC treatment, whereas that of VaXTH1 or VaXTH2, which exhibits only transglucosylase activity toward xyloglucans, was not affected by ACC treatment. The suppression of xyloglucan-degrading activity by downregulating VaXTHS4 expression may be responsible for the increase in the molecular mass of xyloglucan. Our results suggest that the modification of xyloglucan metabolism is necessary to decrease cell wall extensibility, thereby inhibiting the elongation growth of epicotyls in ACC-treated azuki bean seedlings.

Эффективность предпосевной обработки семян Vigna unguiculata subsp. sesquipedalis, Triticum aestivum L., Raphanus sativus L., Allium cepa L. оксидом кремния

Abstract. The purpose of the study was to test the effect of an aqueous solution of silicon oxide on the sowing qualities of plant seeds. Methods. The assessment of the effect of silicon oxide (SiO2) on the sowing qualities of seeds was carried out by a laboratory method according to Medical and biological safety assessment of nanomaterials 1.2.2635-10 and GOST 12038-84 “Seeds of agricultural crops. Methods for determining germination”. Asparagus bean seeds Vigna unguiculata subsp. sesquipedalis of Matilda variety, spring wheat Triticum aestivum L. of Svecha variety, seed radish Raphanus sativus L. of Champion variety and onion Allium cepa L. of Odintsovo variety. The following indicators were taken into account: germination energy and seed germination, number, length and weight of underground and aboveground parts of seedlings. Statistical data processing was carried out by the dispersion method according to B. A. Dospekhov. Scientific novelty. The species-specific reaction of seeds to the treatment with silicon oxide was revealed. The best results in terms of morphometric parameters of seedlings of asparagus bean and spring wheat were obtained when seeds were treated with 0.0025 % silicon oxide, radish – 0.005 %. It is not advisable to treat onion seeds with silicon oxide. According to the research results, asparagus bean seeds turned out to be the most responsive to processing. Germination energy and seed germination in the variant of treatment with 0.0025 % silicon oxide compared to the control (distilled water) were 13.7 % and 3.0 % higher, respectively, but the difference is not significant. The studied concentrations contributed to a significant increase in the average length of the roots. At 0.01 % concentration, this indicator was higher by 30.6 mm, 0.005 % by 30.7 mm, at 0.0025 % by 48.8 mm, respectively (HCP05 = 30.1). The average root weight was 67.5 mg more in the variant of seed treatment with 0.0025% silicon oxide solution (HCP05 = 41.5).

Growth Performance of Varieties of Bean (Phaseolus vulgaris) Seedlings in Earthworm-Bioturbated Soil and Crab-Bioturbated Soil

Earthworms and crabs are known to influence the physicochemical state of their respective soil habitats through their bioturbation actions. While earthworm-bioturbated soils have been well documented to positively affect plant growth, not much is known about the effects of crab-bioturbated soil on plant growth. In this study, we compared the growth performance of four varieties of Phaseolus vulgaris (bean) seedlings in earthworm-bioturbated soil, crab-bioturbated soil, and unbioturbated soil collected within the same proximity of a wetland habitat. Seeds of Phaseolus vulgaris were planted in replicates in each soil type, and allowed to grow for 15 days. Physical growth was measured using a metre rule. Biochemical growth parameters were measured using standard procedures. The differences in stipule length of bean seedlings grown in all the soil types were generally not significant (p > 0.05). However, seedlings grown in earthworm-bioturbated soil and crab-boturbated soil recorded significantly higher (p < 0.05) stipule weight, relative to those grown in unbioturbated soil. Bean seedlings grown in earthworm-bioturbated soil recorded the highest and significant (p < 0.01) concentrations of chlorophyll, total sugar, starch, nitrogen, and crude protein, relative to those grown in crab-bioturbated and unbioturbated soils. This was followed by seedlings grown in crab-bioturbated soil which recorded significantly higher (p < 0.01) concentrations of these biochemical parameters, relative to those grown in unbioturbated soil. The significantly higher biochemical and marginally better physiological growth recorded for seedlings in bioturbated soils indicate that earthworms and crabs both contribute significantly to wetland productivity, through their bioturbatiion activities.

Preparation and Influencing Factors of Sodium Lignosulfonate Nanoparticles

Lignin sulfonate, a by-product of pulp or fiber pulp production using the sulfite method, is directly extracted in its paper mill waste red liquor and is a non-toxic resource with a wide range of sources, low cost and renewable.In this paper, we combined nanotechnology with low-cost and abundant sodium lignosulfonate to prepare nano-sodium lignosulfonate preparation by nanotechnology, so as to improve its adsorption of zinc ions, and to study and investigate the effects of nano- and non-nano-sodium lignosulfonate treatment solution after adsorption of zinc ions on seedlings of wheat and mung beans by measuring the morphological and physiological and biochemical indexes of seedling growth and development. It will provide technical support for the treatment of heavy metal pollution in water environment and the agricultural application of treatment solution for zinc pollution, as well as the prevention of secondary pollution in water bodies after heavy metal treatment.The main research works are: (1) preparation of nano-sodium lignosulfonate formulations, focusing on the mass ratio of sodium lignosulfonate and sodium tripolyphosphate (STPP), magnetic stirring time, ultrasonic shaking time, pH value of the reaction system, and selection of suitable temperature; (2) characterization of the morphological structure of nano-sodium lignosulfonate formulations by laser pens, scanning electron microscopy, and optical microscopy; (3) The adsorption performance of nano-sodium lignosulfonate formulations on Zn²⁺ was studied, and the adsorption performance and effect of nano- and non-nano-sodium lignosulfonate formulations on Zn²⁺ were compared and observed.

Study on the Effect of Sodium Nano Lignin Sulfonate on the Growth and Development of Mung Bean Seedlings

Study on the Effect of Sodium Nano Lignin Sulfonate on the Growth and Development of Mung Bean Seedlings

Applied Selenium as a Powerful Antioxidant to Mitigate the Harmful Effects of Salinity Stress in Snap Bean Seedlings

Selenium (Se) plays several significant roles in regulating growth, development and plant responses to various abiotic stresses. However, its influence on sulfate transporters (SULTRS) and achieving the harmony with other salt-tolerance features is still limited in the previous literatures. This study elucidated the effect of Se supplementation (5, 10 and 20 µM) on salt-stressed (50 mM NaCl) snap bean seedlings. Generally, the results indicated that Se had dual effects on the salt stressed seedlings according to its concentration. At a low level (5 µM), plants demonstrated a significant improvement in shoot (13.8%) and root (22.8%) fresh weight, chlorophyll a (7.4%), chlorophyll b (14.7%), carotenoids (23.2%), leaf relative water content (RWC; 8.5%), proline (17.2%), total soluble sugars (34.3%), free amino acids (FAA; 18.4%), K (36.7%), Ca (33.4%), K/Na ratio (77.9%), superoxide dismutase (SOD; 18%), ascorbate peroxidase (APX;12.8%) and guaiacol peroxidase (G-POX; 27.1%) compared to the untreated plants. Meanwhile, most of these responses as well as sulfur (S), Se and catalase (CAT) were obviously decreased in parallel with increasing the applied Se up to 20 µM. The molecular study revealed that three membrane sulfate transporters (SULTR1, SULTR2 and SULTR 3) in the root and leaves and salinity responsive genes (SOS1, NHX1 and Osmotin) in leaves displayed different expression patterns under various Se treatments. Conclusively, Se at low doses can be beneficial in mitigating salinity-mediated damage and achieving the functioning homeostasis to tolerance features.

The effect of mung bean seedlings juice (&lt;i&gt;Vigna radiata (L.&lt;/i&gt;) Wilczek.) on growth processes and protection against phytopathogens of spring wheat (&lt;I&gt;Triticum aestivum L.&lt;/I&gt;) at early stages of organogenesis

Relevance. Mung bean is a new culture of versatile use for the Middle Volga region; it has a complex of valuable economic and biological properties. When studying seeds, seedlings and mung bean plants as raw materials for the pharmaceutical industry, it was revealed that this culture also has a biocidal effect on phytopathogens. The purpose of our research is to study the biological activity of the juice from the sprouts of mung bean on the seedlings of spring soft wheat for the subsequent creation of theoretical foundations for the development and use of mung bean as a growth stimulant and protection of wheat seedlings from phytopathogenic organisms.Methods. To obtain juice, three-day seedlings of mung bean of the Saltan variety were taken. Three varieties of spring soft wheat created at the Volga Research Institute of Breeding and Seed Production named after P.N. Konstantinov were used in the experiments — Kinelskaya 2020, Kinelskaya jubilee, Kinelskaya Zvezda.Results. The effect of juice from green and etiolated mung bean seedlings on phytopathogens and the growth of spring wheat seeds in the early stages of organogenesis was studied. It was found that the juice of green seedlings has a pronounced biocidal and stimulating activity. Thus, in the tested variants, the formation of primary roots exceeded the control by 15–26%, the length of primary roots exceeded the control by 248– 297% and the length of sprouts — by 337–403%. There were no signs of damage in all tested variants. In the juice of etiolated seedlings, such activity is less pronounced. Only at a concentration of cell juice of 1% in the studied wheat varieties, an excess over the control was observed: the formation of primary roots — by106–112%, the length of primary roots — by109–127% and the length of sprouts 108–125%. In other versions of this experiment, the results were ambiguous. The defeat of phytopathogens manifested itself, but the number of affected wheat seeds decreased as the concentration of cell juice solutions increased.

Effect of zinc nanoparticles on the growth and biofortification capability of mungbean (Vigna radiata) seedlings.

The online version contains supplementary material available at 10.1007/s11756-022-01269-3.

Pathogenicity study of Rhizoctonia solani and its integrated management on different crop species in Morocco

In this work, we aimed to develop an ecofriendly strategy to manage the R. solani damping-off incidence of Moroccan strains. After the assessment of damping-off incidence on different crops, a greenhouse experiments were carried out to assess the efficiency of chemical and biological agents on plant growth and damping-off control. Results revealed that R. solani MN191236 strain was the most virulent as it dramatically increased severity indexes and reduced root length and pods number by 23% and 58% respectively. On R. solani-infested bean seedlings, Trichoderma asperellum increased pods number by 169% and reduce the severity index up to 1.33. However, the Tolclofos-methyl and the hypovirulent F. oxysporum strain came in second place. The efficiency of chemical or biological agents was significantly related to the interaction ‘pathogenic strains*fungicide or biological agents’. These results are promising in term of integrally and eco-friendly management of R. solani damping-off.

Phyto-Synthesis, Characterization, and In Vitro Antibacterial Activity of Silver Nanoparticles Using Various Plant Extracts.

Aloe vera, Mentha arvensis (mint), Coriandrum sativum (coriander), and Cymbopogon citratus (lemongrass) leaf extracts were used to synthesize stable silver nanoparticles (Ag-NPs) by green chemistry. UV-vis spectrophotometry, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) spectroscopy techniques were used to characterize these biosynthesized nanoparticles. The data indicated that the silver nanoparticles were successfully synthesized, and the narrower particle size distribution was at 10-22 nm by maintaining a specific pH. As a short-term post-sowing treatment, Ag-NP solutions of different sizes (10 and 50 ppm) were introduced to mung bean seedlings, and the overall increase in plant growth was found to be more pronounced at 50 ppm concentration. The antibacterial activity of Ag-NPs was also investigated by disc diffusion test, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) test. The zones of inhibition (ZOI) were shown by Escherichia coli (E. coli) (1.9, 2.1, 1.7, and 2 mm), followed by Staphylococcus aureus (S. aureus) (1.8, 1.7, 1.6, and 1.9 mm), against coriander, mint, Aloe vera, and lemongrass, respectively. MIC and MBC values of E. coli, and S. aureus ranged from 7 to 8 µg/mL. Overall, this study demonstrates that Ag-NPs exhibit a strong antimicrobial activity and thus might be developed as a new type of antimicrobial agent for the treatment of bacterial infection.

Colletotrichum truncatum-A New Etiological Anthracnose Agent of Sword Bean (Canavalia gladiata) in Southwestern China.

Anthracnose is a disease caused by Colletotrichum species. They are well known as major plant pathogens, and a black stem disease, specifically caused by Colletotrichum truncatum and primarily infecting sword bean (Canavalia gladiata), was observed in the Yunnan province, China. To aid disease management and to determine pathogenic characteristics, the species causing the leaf spot disease of hairy vetch was verified as C. truncatum. A sequence analysis of the ITS, ACT, GAPDH, and HIS3 genes was conducted, as well as morphological and cultural characteristics, to identify this Colletotrichum species, which has curved conidia. C. truncatum isolates from sword bean formed a distinctive group among Colletotrichum species, including those that infect other forage and field crops. Artificially inoculated sword bean seedlings showed typical symptoms of anthracnose, which were similar to field observations. To the best of our knowledge, this is the first report of C. truncatum causing black stem disease on sword beans in China.

Ameliorative Effects of Biochar for Cadmium Stress on Bean (Phaseolus vulgaris L.) Growth

In order to investigate the changes in the morphological and biochemical characteristics of bean plants in response to biochar treatment under cadmium (Cd) stress, a pot experiment was conducted in a greenhouse. Bean plants were subjected to different amounts of Cd (0, 100, 150 and 200 mg kg−1) and biochar applied at different doses (0, 2.5 and 5%). Under Cd stress, the growth and development of bean seedlings were remarkably inhibited, whereas the biochar treatment could effectively improve the heavy metal tolerance of bean seedlings. Cd stress caused an increase in the hydrogen peroxide (H2O2), malondialdehyde (MDA), proline and sucrose content, catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) activity of leaves. However, biochar treatments reduced the CAT, POD and SOD activity of bean seedlings. Growing beans on Cd medium led to a significant reduction in plant nutrient element content. However, biochar amendment to the soil elevated the plant nutrient element content compared to untreated soil. Cd content of the bean seedlings increased with increasing Cd doses. There was a sharp decrease in available concentration for Cd with the addition of biochar. In conclusion, biochar incorporation into the soil can alleviate the adverse impacts of Cd stress on the growth of bean seedlings.

Growth Performance and Metabolic Changes in Susceptible Mung Bean [Vigna radiata (L.) Wilczek] during Interaction with Rhizoctonia solani and Trichoderma virens

Background: Mung bean is susceptible to Rhizoctonia solani infection. Applications of beneficial microorganisms such as Trichoderma are promising for controlling pathogens and promoting plant growth. Methods: This study investigated growth performance and metabolic changes in mung bean seedlings during interaction with R. solani and Trichoderma virens using Gas Chromatography-Mass Spectrometry (GC-MS). Result: Mung bean infected by R. solani caused root rot and wilting. T. virens treatment reduced the disease severity in infected seedlings and promoted mung bean growth. Seventy-eight metabolites were identified in root extracts and dominated by sugars and fatty acids. The sugars, fatty acids and organic acids were significant metabolite groups that changed in response to pathogen infection and/or T. virens treatment. Five metabolic pathways particularly pyruvate metabolism, glyoxylate and dicarboxylate metabolism, sulfur metabolism, citrate cycle (TCA cycle) and phenylalanine, tyrosine and tryptophan biosynthesis altered significantly based on a metabolic pathway analysis. Acetic acid and aconitine had important roles in mung bean response to R. solani infection and/or T. virens treatment.

First Report of Root and Hypocotyl Rot of Dry Bean Caused by Aphanomyces euteiches in Alberta, Canada.

Dry bean (Phaseolus vulgaris L.) is a high-value crop grown under irrigation on 45,000 ha in southern Alberta, Canada. In 2019, one field of red beans showed premature yellowing and stunting of shoots in mid-July near Bow Island, AB. Roots had brown lesions along the length of hypocotyl and tap root, and decay and sloughing of the root cortex of lateral roots (Fig. 1). Roots were washed for 10 min under running tap water, and portions of the lesions were excised for DNA extractions using the Plant DNeasy kit (Qiagen) and multiplex PCR assays for an array of pathogens, which included Aphanomyces euteiches (Chatterton et al. 2019). Lesion pieces were also surface sterilized and plated onto PDA or cornmeal agar amended with metalaxyl, benomyl and vancomycin (CMBV) and visualized microscopically for oospores. The roots were PCR positive for A. euteiches, Rhizoctonia solani, and Pythium ultimum. Isolations yielded R. solani, and Fusarium spp. on PDA, but cultures on CMBV were over-grown with Rhizopus. Oospores measuring 24.7 +/- 1.08 m, consistent with the expected size of A. euteiches oospores of 18 - 25 m (Papavizas and Ayers, 1974), were visible in some of the root pieces. To obtain an A. euteiches isolate, soil was collected from three areas of the red bean field and used in a bait assay. Tests were performed using pea (cv. CDC Meadow) and dry bean (cv. Redbond) seeds treated with metalaxyl. Five seeds per pot were planted into field soils in 10-cm pots with 4 replicate pots/field. Soils were watered as needed until the 2nd node stage and then kept at saturation for 14 days, at which time roots were washed. Roots from the dry bean, but not the pea, plants showed severe root rot, including honey-brown discolouration of the lateral roots and extending to the hypocotyl, degradation of the root cortex, and presence of oospores. Diseased root pieces were plated onto CMBV without surface sterilization. Cultures with fast growing, white, aerial mycelia characteristic of A. euteiches on CMBV were recovered from dry bean roots from the three soil samples, considered as three isolates, and were transferred to PDATo confirm identity, total DNA was extracted from 7-day old cultures of the three isolates growing on PDA using the Qiagen DNeasy Plant Kit. The ribosomal DNA internal transcribed spacer (ITS) region was amplified using the primer pair ITS1 and ITS4, and sequenced (White et al. 1990). The sequences, deposited in GenBank with accession numbers OM976770, OM976771, and OM976772, were 100% identical to the ITS rDNA sequence of several isolates of A. euteiches (e.g. KM486066.1; 669/669 bp; 670/670 bp; 670/670 bp) using a BLASTn query and 99.7% identical to the CBS15773 voucher specimen (HQ643116.1, 661/663 bp; 662/664 bp; 662/664 bp). To confirm pathogenicity of these three isolates, cultures were used to produce zoospores for inoculating 14-day old red bean and pea seedlings (Chatterton et al. 2015). Control plants received minimal salt media solution and did not develop symptoms. Dry bean, but not pea, seedlings displayed root rot symptoms (Fig. 2). A. euteiches was re-isolated from dry bean seedlings by plating onto CMBV, and identity confirmed as described above. Although a previous survey detected A. euteiches in a small number of dry bean fields in southern Alberta (Chatterton et al. 2019), tests to confirm Koch's postulates were not performed. Aphanomyces root rot can be a devastating pathogen of pulse crops. Precautionary measures should be taken to prevent spread of this pathogen in the small dry bean growing area of southern Alberta by encouraging producers to use rotation intervals, monitoring movement of the pathogen, and evaluating cultivars for resistance to this pathogen.

Harnessing the phosphate-solubilizing ability of Trichoderma strains to improve plant growth, phosphorus uptake and photosynthetic pigment contents in common bean (Phaseolus vulgaris)

A promising strategy for dissolving, mobilizing and enhancing the utilization of the complexed form of phosphorus (P) in soil-plant systems is the use of effective phosphate solubilizing microorganisms. In the present study, six strains of Trichoderma spp. previously obtained from the common bean rhizosphere were investigated for their ability to solubilize tricalcium phosphate (TCP) in NBRIP (National Botanical Research Institute Phosphate) broth medium. All six strains were able to solubilize TCP to various extents, with solubilization ranging from 66.9 μg/ml to 328.4 μg/ml. A significant negative linear correlation (r = - 0.94; p < 0.01) was found between solubilized P and the pH of the culture medium. The highest solubilization activity (328.4 μg/ml), fungal growth (87.21 mg/100 ml) and pH fluctuation (7.0–4.06) were achieved by Trichoderma gamsii It-62. Under pot conditions, inoculation with Trichoderma gamsii It-62 remarkably improved plant height, shoot and root weight, P uptake, photosynthetic pigments and total protein content compared with untreated common bean seedlings. These increases were significantly higher upon combined inoculation of the bioagent with TCP addition. The obtained results indicate that Trichoderma gamsii It-62 might be a promising alternative for the release of fixed forms of phosphates present in the soil, thereby increasing soil fertility.

EVALUATION OF WATER STRESS AND CO-INOCULATION OF AZOSPIRILLUM BRASILENSE AND RHIZOBIUM TROPICI IN BEANS (PHASEOLUS VULGARIS L.)

Climate change has caused major changes in abiotic factors, with water stress as the greatest threat to agricultural production. The measures aimed at alleviating the problems caused by this limiting production factor have occurred through the adoption of sustainable strategies, especially microbial biotechnology, which uses the interactions between the microorganism and the plant, ensuring productive quality and inducing plant resistance to stresses biotic and abiotic. The objective of the present work was to evaluate the biological nitrogen fixation and the development of bean seedlings, with co-inoculation of two types of inoculants, which were subjected to water stress by different pot capacities. The experiment was conducted in a greenhouse, at Universidade Paranaense - UNIPAR, from April to June 2019. The experimental design was completely randomized (DIC), with 5 replications, 16 treatments and 80 experimental units. The cultivar used was SCS Riqueza. The parameters evaluated were pot capacity (25%, 50%, 75% and 90%); small, large and total nodules, shoot and root length, dry and fresh weight, total carbon and nitrogen. The evaluation of the morphological parameters of the bean seedlings indicated that the co-inoculation technique promoted beneficial effects for the dry mass parameters of shoot, nodule and root. The analysis of the percentage of carbon and nitrogen in the tissues of the seedlings provided an increase in the concentration of these elements in treatments that involved co-inoculation (Azospirillum brasilensis and Rhizobium tropici) with pot capacities of 25 and 75% (CV), demonstrating that the association of microorganisms is beneficial in the limiting water situation.

Transcriptome profiling provides new insights into ABA-mediated genes and pathways in leaves, stems, and roots of mung bean seedlings

Transcriptome profiling provides new insights into ABA-mediated genes and pathways in leaves, stems, and roots of mung bean seedlings