Root Research Articles

Influence of electron radiation of spring barley seeds on phytopathogenic microflora

Under the conditions of a model pot experiment, the effect of electron irradiation on the phytopathogenic microflora of plant roots and leaves was studied. The studies were carried out on spring barley seeds of the Vladimir variety (reproduction 1), affected by helminthosporiosis (pathogen Bipolaris sorokiniana Shoem.), (natural infectious background). This pathogen causes root rot and leaf spot. The grain was irradiated using a wide-aperture electron accelerator “Duet” with a mesh plasma cathode and the output of the generated beam of a large cross-section into the atmosphere in doses of 1, 2, 3, 4 and 5 kGy. The total administered dose was increased by changing the number of pulses. The radiation dose rate was 100 Gy/pulse, the electron energy was 130 keV (mode 1) and 160 keV (mode 2). The depth of dose absorption did not exceed 300 μm. Based on the conducted studies on the effect of electron irradiation on root rot (pathogen Bipolaris sorokiniana) of spring barley, it was noted that in the tillering and heading phases, when irradiating seed material with a dose of 2 kGy in mode 1 (130 keV), the disease incidence and prevalence decreased by more than 1.5 times compared to the non-irradiated control. In the phase of full grain maturity, the highest value of root infestation (45–50%) and prevalence (95–100%) of Bipolaris sorokiniana were recorded, but statistically significant differences between the irradiated variants and the control were absent. The records of the damage of vegetative plants showed that in the tillering phase, for all irradiation variants in mode 1, the degree of damage to leaves 1–3 increased by 23% compared to the control, and in the heading phase, the degree of damage to the upper leaves (1–3) exceeded the control when irradiated at doses of 2–5 kGy (mode 1) and 1–5 kGy (mode 2) – 2.1–2.8 times for 1 leaf, 1.9–2.0 times for 2 leaves and 1.2 times for 3 leaves.

Within-Site Variations in Soil Physicochemical Properties Explained the Spatiality and Cohabitation of Arbuscular Mycorrhizal Fungi in the Roots of Cryptomeria Japonica

Arbuscular mycorrhizal fungi (AMF) live in a community in the roots of host plants. Still, the patterns and factors that drive their spatiality and cohabitation remain uncovered, particularly that of trees in planted forests, which we aimed to clarify in Cryptomeria japonica, a major plantation tree in Japan. We analyzed 65 paired root and soil samples of Cryptomeria japonica trees collected from 11 microsite (MS) plots at two environmentally different forest sites in central Japan and measured soil pH, total phosphorus (TP), C, N, and the carbon-to-nitrogen ratio. Root AMF communities were recovered using Illumina’s next-generation amplicon sequencing targeting the small subunit of ribosomal DNA. We detected more than 500 AMF OTUs at each site but only three belonging to Dominikia, Rhizophagus, and Sclerocystis were dominant in the roots of C. japonica, detected each at an average relative abundance higher than 20%. Two showed negatively correlated spatial distributions and different associations with soil pH. Similarly, the physicochemical properties at MSs significantly determined the AMF assemblages in the roots of C. japonica. Dominikia, Rhizophagus, and Sclerocystis coexist in the roots of C. japonica where soil physicochemical properties, particularly pH, determine their spatial dynamic, turnovers, and cohabitation patterns. These findings highlight the importance of simultaneous colonization of plants by multiple AMF.

Biochar application improves maize yield on the Loess Plateau of China by changing soil pore structure and enhancing root growth

Biochar application emerges as a valuable soil management strategy for enhancing crop yield; however, the mechanisms underlying the relationships between soil and plants remain unclear after biochar application. In this study, soil pore characteristics and maize yield were assessed in a five-year biochar-application experiment on the Loess Plateau of China, including four treatments: Control (no biochar), low-dose biochar application (LB, 3 t ha−1), moderate-dose biochar application (MB, 6 t ha−1), and high-dose biochar application (HB, 9 t ha−1). Root growth traits were evaluated by cultivating maize in intact soil cores collected from field conditions using X-ray computed tomography. Our findings indicate that, compared to the Control, the HB treatment enhanced macroporosity (> 0.1 mm in diameter), porosity of 0.1–0.5 mm pores, and saturated water content, while reducing macropore connectivity and penetration resistance. However, biochar application treatments did not alter the water retention characteristics from field capacity to permanent wilting point or the plant-available water content (PAWC). Furthermore, the mean angle of primary and seminal roots as well as the length and surface area of entire roots increased in the HB treatment, showing a positive correlation with the porosity of 0.1–0.5 mm pores. The mean diameter of primary and seminal roots, leaf fresh and dry weights, and maize yield also increased in the HB treatment compared to the Control. Partial least squares path modeling analysis indicated that biochar application rates positively impacted on root growth and plant productivity through an indirect influence of soil pore size distribution, with 0.1–0.5 mm pores being particularly crucial for facilitating deeper root penetration and root elongation. These findings demonstrate that biochar application primarily augmented 0.1–0.5 mm pores, rather than affecting smaller pores capable of retaining plant-available water or larger macropores, enhancing deeper rooting and root elongation, thus improving plant productivity and crop yield.

EVALUASI TIGA MACAM AUKSIN SINTETIK TERHADAP PERTUMBUHAN AKAR LIDAH MERTUA

The propagation of snake plants is efficient when using leaf organs. However, the problem is the growth of roots. Auxin is a plant growth regulator that can stimulate root growth. There are several synthetic auxins and must be applied to obtain the best results in snake plant root growth. The materials used in this experiment were snake plant leaves, synthetic auxin (AUKSIN, Rootone-F, and Atonik), soil, and containers. The tools used included a cutter, ruler, stationery, and camera. Synthetic auxin was applied by smearing it on one part of the leaf base. The experimental design was a Completely Randomized Design, with four treatments: control (without auxin), AUKSIN, Rootone-F, and Atonik. Each treatment had three replications, resulting in twelve experimental units. The data obtained were analyzed using ANOVA and followed by DMRT. The results showed that snake plants treated with Atonik produced the best results and differed from the control significantly.

Probiotic model for studying rhizosphere interactions of root exudates and the functional microbiome.

Root exudates are important mediators of plant-microbiome interactions. Recent pioneering studies on various aerial root plants, including cereals, have shown that carbohydrate-rich mucilage can enrich diazotrophs and increase host nitrogen utilization and growth. Moreover, non-diazotrophic "gatekeeper" microorganisms in mucilage help defend against pathogenic and environmental microbes. These findings highlight the active role of root exudates in mediating plant-microbiome interactions to maintain microbial homeostasis in the rhizosphere. However, little is known about the specific mechanisms by which root exudates modulate the functional microbiome and homeostasis in rhizosphere microhabitats. Here, we propose the typical and stable biointeractions of four plant-specific aerial root mucilage-probiotic systems as a model for understanding root exudate-functional microbiome interaction. We anticipate that this model can provide fundamental biological insights into rhizosphere interactions.

Foliar Application of Methyl Jasmonate and Chitosan Improve Growth, Yield, and Quality of Guar (Cyamopsis tetragonoloba L.) Under Water-Deficit Stress

Guar (Cyamopsis tetragonoloba L.), a summer legume, is becoming increasingly important as an industrial crop due to its high gum and viscosity content. This study investigated the effects of methyl jasmonate (MeJA), chitosan (CH), and their combination on the growth, yield, and quality of guar under irrigation regimes. A greenhouse experiment was conducted using a factorial design to evaluate the effect of foliar spraying with MeJA (5, 25, and 50 µM), CH (100, 150, and 200 mg/L), their combination (25 µM MeJA + 150 mg/L CH), and control on two commercial guar varieties (RGC-986 and BR-2017) under different irrigation regimes (100%, 70%, and 40% field capacity). The results showed that the exogenous application of MeJA and CH, individually and in combination, significantly enhanced various morphological traits and yield components in guar, including plant height, pod characteristics, seed yield, and root development. Additionally, the combination treatments improved seed quality parameters, such as gum percentage and viscosity content. Leaf analysis revealed increased levels of total phenolic content, total flavonoid, and anthocyanin contents. The BR-2017 variety showed superior performance in most morphological and qualitative traits, demonstrating greater resistance to irrigation regimes. It maintained yield and quality characteristics under water-deficit conditions, particularly when treated with 25 µM MeJA and 150 mg/L CH. The highest gum percentage (33.67%) and viscosity (4768.5 cP) were observed in the RGC-986 variety, along with enhanced levels of secondary metabolites. This study provides new insights into how MeJA, CH, and their combination can improve the yield and quality of guar under water deficit stress conditions. The results suggest that the use of these elicitors, especially in combination, represents an innovative strategy for improving guar production and quality, with potential variety-specific responses to water-deficit stress.

Impact of Bacillus Inoculation on Rhizosphere Bacterial Community Structure: A Review

The rhizosphere is a specialized zone where plant roots interact with the soil microbiome. Among various beneficial microbes, the genus Bacillus stands out due to its diverse functionalities and potential to boost plant growth and resilience. Bacillus is a key genus of plant growth-promoting rhizobacteria (PGPR) known for enhancing nutrient availability, producing phytohormones, and inducing plant resistance to pathogens. Inoculating Bacillus species into the rhizosphere can significantly alter the bacterial community's structure and composition. These alterations are driven by the competitive and cooperative interactions between Bacillus and the native rhizosphere microorganisms. Incorporating soil microorganisms into the host plant's beneficial bacterial community improves soil nutrient cycling and nutrient use efficiency. Using microbial inoculants is an effective strategy to address crop succession challenges, enhance microbial community structure, and improve soil fertility, thereby promoting crop growth. This review thoroughly examines the current understanding of how Bacillus inoculation impacts rhizosphere bacterial community structure.

Benefit of weeds for crop-plant mycobiota in agroecosystems: Integrating ecological demonstration and management applicability

Agricultural intensification reduces not only biodiversity in agroecosystems but also key ecosystem functions such as soil fertility. By reintroducing biological diversity in fields, weeds may enhance soil biological fertility through their influence on crop microbiota. However, letting weeds grow in crop fields will depend on weed competitiveness, farmers’ perception and acceptance, and on crop management, which influences the occurrence and the abundance of weeds in the field. This study assessed the use of eight weed species to modify wheat plant root endospheric mycobiota, and the applicability of using these plants for mycobiota enrichment in the field. By combining controlled lab experiments and field studies, we demonstrated that weeds act either as a refuge for a high diversity of fungi or as a vector for transferring fungi to the crop, particularly symbionts. Weeds differed in their competitive effect on wheat growth and only three species significantly reduced wheat growth. Interviews with farmers’ revealed that weed species were better known and more appreciated in crop fields by organic farmers than by conventional farmers. Floristic surveys confirmed that both weed occurrence and cover were higher in organic fields than in conventional fields. A multicriteria analysis showed that Trifolium repens and V. persica had the highest potential for promoting wheat plant mycobiota. Among the weed species tested, these two are worth considering as auxiliaries to improve soil biological fertility in crop fields. Their use with the goal of selecting appropriate crop mycobiota should be relatively easier in organic farms where weeds are better accepted, whereas their use in conventional farms would require raising farmers’ awareness of the benefits of weeds for soil fertility.

Impacts of root exudates on the toxic response of Chrysanthemum coronarium L. to the co-pollution of nanoplastic particles and tetracycline

Nano polystyrene (PS) particles and antibiotics universally co-exist, posing a threat to crop plants and hence human health, nevertheless, there is limited research on their combined toxic effects along with major influential factors, especially root exudates, on crop plants. This study aimed to investigate the response of Chrysanthemum coronarium L. to the co-pollution of nanoplastics and tetracycline (TC), as well as the effect of root exudates on this response. Based on a hydroponic experiment, the biochemical and physiological indices of Chrysanthemum coronarium L. were measured after 7 days of exposure. Results revealed that the co-pollution of TC and PS caused significant oxidative damage to the plants, resulting in reduced biomass. Amongst the two contaminants, TC played a more prominent role. PS could enter the root tissue, and the uptake of TC and PS by plant roots was synergetic. Malic acid, oxalic acid, and formic acid could explain 65.1% of the variation in biochemical parameters and biomass of the roots. These compounds affected the photosynthesis and biomass of Chrysanthemum coronarium L. by gradually lowering root reactive oxygen species (ROS) and leaf ROS. In contrast, the impact of rhizobacteria on the toxic response of the plants was relatively minor. These findings suggested that root exudates could alleviate the toxic response of plants to the co-pollution of TC and PS. This study enhances our understanding of the role of root exudates, providing insights for agricultural management and ensuring food safety.

Comprehensive studies of the serine carboxypeptidase-like (SCPL) gene family in Carya cathayensis revealed the roles of SCPL4 in epigallocatechin-3-gallate (EGCG) synthesis and drought tolerance

Hickory (Carya cathayensis) nuts are rich in epigallocatechin-3-gallate (EGCG) with multiple health functions. EGCG also regulates plant growth, development and stress responses. However, research on the synthesis mechanism of EGCG and its function in hickory is currently limited. Herein, 44 serine carboxypeptidase-like (SCPL) members were identified from the hickory genome and classified into three major categories: SCPL-I, SCPL-II, and SCPL-III. In the CcSCPLs-IA branch, CcSCPL3/4/5/8/9/11/13 showed differential expression patterns in various tissues, especially with relatively high expression levels in plant roots, female flowers and seed coat. These proteins have a catalytic triad composed of serine (Ser), aspartic acid (Asp) and histidine (His). Ser-His in the triad and arginine (Arg) mediated the docking of CcSCPL3/4/5/11 with 1-O-galloyl-β-d-glucose (βG) and epigallocatechin (EGC), whereas the Asp of the triad did not. CcSCPL4 was further confirmed to promote the synthesis of EGCG in tobacco leaves. CcSCPL4 may function as monomer and be mainly localized within cellular structures outside the nucleus. Notably, the expression level of CcSCPL4 significantly changed after drought, cold, and salt stress, with the highest expression level under drought stress. Meanwhile CcSCPL4 over-expression could enhance the drought resistance of Saccharomyces cerevisiae and Arabidopsis. This study elucidates key enzymes for EGCG synthesis and their role in drought resistance, providing insights into the EGCG synthesis pathway and molecular breeding of hickory in future.

Commodity risk assessment of Betula pendula and Betula pubescens plants from the UK.

The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by plants of Betula pendula and B. pubescens imported from the United Kingdom (UK) taking into account the available scientific information, including the technical information provided by the UK. The commodities were grouped in the risk assessment as (a) bundles of 10-20 graftwood/budwood (up to 1-year-old), (b) bare root plants which include bundles of 25 or 50 seedlings or transplants (1-2 years-old), bundles of 5, 10 or 15 whips (1-2 years-old) and single bare root plants (1-7 years-old), (c) plants in pots which include bundles of 5 and 10 cell-grown plants (1-2 years-old) and rooted plants in pots (1-7 years-old), and (d) large specimen trees up to 15-years-old. All pests associated with the commodities were evaluated against specific criteria for their relevance for this opinion. Two EU quarantine pests i.e. Meloidogyne fallax and Phytophthora ramorum (non-EU isolates) and two protected zone quarantine pests i.e. Entoleuca mammata and Thaumetopoea processionea fulfilled all relevant criteria and were selected for further evaluation. For the selected pests, the risk mitigation measures described in the technical dossier from the UK were evaluated considering the possible limiting factors. For these pests an expert judgement is given on the likelihood of pest freedom taking into consideration the risk mitigation measures acting on the pest, including uncertainties associated with the assessment. In the assessment of risk, the age of the plants was considered, as larger trees are more likely to be infested mainly due to longer time grown in the field. In addition, larger canopies and root systems are more difficult to inspect, thereby making the detection of pests more challenging on large trees. The likelihood of pest freedom varies among the pests evaluated, with M. fallax being the pest most frequently expected on the imported plants. The Expert Knowledge Elicitation (EKE) indicated with 95% certainty that between 9735 and 10,000 per 10,000 large specimen trees will be free from M. fallax.

Shikonin Stimulates Mitochondria-Mediated Apoptosis by Enhancing Intracellular Reactive Oxygen Species Production and DNA Damage in Oral Cancer Cells.

Phytotherapy has rendered a new insight towards the treatment of various cancers, including oral cancer with fewer side effects, over the traditional chemotherapeutic drugs to overcome chemoresistance. Shikonin (Shk) is a natural biologically active alkaloid found in the Lithospermum erythrorhizon plant's root. It has potent cytotoxic activities against various cancers. Our study revealed the release time and anticancer potential of Shk on the SCC9 and H357 oral cancer cell lines. We investigated the antiproliferative, antimigratory, cell cycle arresting and apoptosis promoting activity of Shk in oral cancer cells by performing MTT and morphological assay, colony, and tumor sphere formation assay, AO/EtBr and DAPI staining, Annexin V-FITC/PI staining, assay for reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) measurement, comet assay, qRT-PCR, and western blot analysis. We also checked the interaction of DNA and Shk by docking and CD spectroscopy and EtBr displacement assay. As a result, we found that Shk reduced the viability, proliferation, and tumorigenicity of SCC9 and H357 cells in a time and concentration-dependent manner. We obtained half-maximal inhibitory concentration (IC50) at 0.5 µM for SCC9 and 1.25 µM for H357. It promotes apoptosis via overexpressing proapoptotic Bax and caspase 3 via enhancing ROS that leads to MMP depletion and DNA damage and arrests cells at the G2/M & G2/S phase. The antimigratory activity of Shk was performed by analyzing the expression of markers of epithelial-mesenchymal transition like E-cadherin, ZO-1, N-cadherin, and vimentin. These overall results recommended that Shk shows potent anticancer activity against oral cancer cell lines in both in vitro and ex vivo conditions. So, it could be an excellent agent for the treatment of oral cancer.

Heterologous biosynthesis of betanin triggers metabolic reprogramming in tobacco

Engineering of a specialized metabolic pathway in plants is a promising approach to produce high-value bioactive compounds to address the challenges of climate change and population growth. Understanding the interaction between the heterologous pathway and the native metabolic network of the host plant is crucial for optimizing the engineered system and maximizing the yield of the target compound. In this study, we performed transcriptomic, metabolomic and metagenomic analysis of tobacco (Nicotiana tabacum) plants engineered to produce betanin, an alkaloid pigment that is found in Caryophyllaceae plants. Our data reveals that, in a dose-dependent manor, the biosynthesis of betanin promotes carbohydrate metabolism and represses nitrogen metabolism in the leaf, but enhances nitrogen assimilation and metabolism in the root. By supplying nitrate or ammonium, the accumulation of betanin increased by 1.5–3.8-fold in leaves and roots of the transgenic plants, confirming the pivotal role of nitrogen in betanin production. In addition, the rhizosphere microbial community is reshaped to reduce denitrification and increase respiration and oxidation, assistant to suppress nitrogen loss. Our analysis not only provides a framework for evaluating the pleiotropic effects of an engineered metabolic pathway on the host plant, but also facilitates the development of novel strategies to balance the heterologous process and the native metabolic network for the high-yield and nutrient-efficient production of bioactive compounds in plants.

Identification, functional characterization and expression profiling of three triterpene synthases from the legume plant Vigna unguiculata

Oxidosqualene cyclases (OSCs) are important regulatory enzymes involved in cyclization reactions of 2, 3-oxidosqualene to form triterpenes and sterols. This study presents the identification and characterization of three OSC genes, a β – amyrin synthase (VuβAS), a lupeol synthase (VuLUS) and a cycloartenol synthase (VuCAS) in Vigna unguiculata, an edible leguminous plant with high nutritional and nutraceutical value. Phylogenetic analysis showed that the VuβAS, VuLUS and VuCAS were clustered within the clades of previously characterized β – amyrin synthases, lupeol synthases and cycloartenol synthases. Heterologous expression in Saccharomyces cerevisiae and Gas Chromatography – Mass Spectrometry (GC – MS) analysis in different plant stages confirmed their specific functions. VuβAS showed higher expression in roots from early germinating seedlings to older plants (4-day to 28-day), while VuLUS expression levels were higher in the roots of older plants only (14-day to 28-day). VuCAS expression was increased in all the tissues of 4-day seedlings, with a peak in stem and leaves and a lower accumulation in radicles. These findings revealed the presence and function of OSC genes in V. unguiculata, and future research could lead to the discovery of promising biologically active compounds.

Genome-wide identification of shaker K+ channel gene family in sugar beet (Beta vulgaris L.) and function of BvSKOR in response to salt and drought stresses

Potassium (K+) is the most abundant cation in plants, which is absorbed by roots and distributed throughout the plants and within plant cells, and is involved in various cellular processes. Shaker K+ channel plays crucial roles in the absorption and distribution of K+ and in the response to abiotic stress in plants. Herein, a total of six shaker K+ channel genes, BvKAT1, BvKAT3, BvAKT1, BvAKT2, BvAKT5, and BvSKOR, were identified in the genome of sugar beet (Beta vulgaris L.). The coding domain sequences (CDS) of these genes ranged from 2232 to 2739bp, and protein lengths were varied from 743 to 912 aa. The shaker K+ channel genes contained hormone-related and light responsiveness cis-acting regulatory elements. The phylogenetic analysis showed that BvSKOR was highly conserved and contained six transmembrane structures. The expression patterns of BvSKOR under salt and osmotic stress were analyzed by qRT-PCR, and found that the expression level of BvSKOR under low concentration salt and osmotic stress at short period of treatment were significantly higher than that of the control group. The function of BvSKOR was further verified in tobacco (Nicotiana tabacum), and the results showed that under salt and osmotic stress, the roots of transgenic plants were significantly stronger than those of wild type (WT) plants, and the relative water content (RWC), chlorophyll, proline, soluble sugar, soluble proteins contents and antioxidant enzyme activity were significantly higher than those of WT plants. These results indicated that overexpression of BvSKOR can significantly enhance the salt and drought tolerance in transgenic tobacco plants. This study could provide theoretical support and genetic resources for genetic improvement of crops stress resistance.

Does succulence in woody plants delay desiccation, and is stored water used to maintain physiological function during drought conditions?

AbstractSucculence is a trait that describes water storage in plant organs and tissues regardless of life form. Plants use the stored water to maintain physiological function and delay desiccation. However, it is unclear whether succulence in leaves, stems and roots of woody plants delays desiccation, whether it provides ‘utilizable water’ to maintain physiological function, or buffers changes in water status in drying soils through capacitance. We conducted a pot dry‐down experiment with nine shrub species to determine whether woody plants with greater leaf, stem, or root succulence have greater shoot utilizable water or capacitance. We also investigated whether greater succulence delays desiccation, represented by cumulative VPD, until evapotranspiration ceased or until utilizable water was exhausted. Greater leaf and stem succulence were strongly related to greater shoot utilizable water and capacitance. However, desiccation time was not delayed in plants with greater total shoot succulence, utilizable water, or capacitance. Instead, woody plants with greater root succulence had longer desiccation times. This suggests that woody plants use aboveground succulence to maintain physiological function and water status during drought, whereas root succulence extends desiccation time. Our study improves the mechanistic understanding of how woody plants use stored water to survive in dryland ecosystems.

Secretory Proteins Are Involved in the Parasitism of Melon by Phelipanche aegyptiaca During the Attachment Stage

Parasitic plants represent a significant challenge in global agriculture, with Broomrape (Orobanche/Phelipanche spp.) being a notable example of a holoparasitic species that targets the roots of host plants. This study employed comparative transcriptomics to investigate the mechanisms underlying the parasitism of P. aegyptiaca on melon, focusing on both resistant and susceptible interactions. The findings indicate that the critical phase of P. aegyptiaca parasitism occurs during the post-attachment stage. It is suggested that peptidases may play a role in the development of invasive cells, while cell wall-degrading enzymes (CWDEs) are likely involved in cell wall modification and degradation, and transferases, elicitors, and effectors may play a role in immune regulation. In this study, 25 tobacco rattle virus (TRV) recombinant vectors were successfully constructed and functionally validated using a host-induced gene silencing assay to explore the functions of candidate-secreted effector proteins. The results revealed that silencing Cluster-107894.0, Cluster-11592.0, and Cluster-12482.0 significantly decreased the parasitism rate of P. aegyptiaca on Nicotiana benthamiana. Notably, Cluster-107849.0 encodes a cellulase with hydrolase activity, Cluster-11592.0 encodes a periodic-dependent kinase inhibitor with phosphoprotein activity, and Cluster-12482.0 encodes a glucan 1,3-β-glucosidase with hydrolase activity. These findings potentially offer a novel theoretical framework and justification for understanding host–parasite plant interactions, and suggest new avenues for developing crop varieties resistant to parasitic infestation.

Effect of Palm Oil Mill Effluent (Pome) Concentration and Soil Type on the Growth of Oil Palm (Elaeis guinensis Jacq) in Pre-Nursery

The place of research was carried out at Educational and Research Garden of the STIPER Agricultural Institute which is located in Maguwoharjo Village, Depok District, Sleman Regency, Yogyakarta, Indonesia. The research location is located 118 meters above sea level. This research was conducted between March to June 2024. Two components make up the factorial experiment used in the Complete Randomized Design (CRD). The soil type had three levels: A1 = latosol soil, A2 = regusol soil, and A3 = grumusol soil, was the first factor. Palm Oil Mill Effluent (POME) concentration was the second factor. It was consisted into four levels: X1 was the control (NPK fertilizer), X2 was 150 ml per polybag, X3 was 300 ml per polybag, and X4 was 450 ml per polybag. So there were 12 treatment combinations (3 x 4 = 12) with 4 repetitions, so all the experiment 48 plants. Analysis of variance (ANOVA) was applied at the significant level of 5% to check the observation data. Duncan's Multiple Range Test (DMRT) was then used at a noticeable 5% level if there was significant difference. The weight parameters of fresh roots and the amount of chlorophyll in the leaves are influenced by the interaction of the soil and POME concentration. The composition, regusol soil and POME 450 ml/polybag provide an optimal combination of treatments. The type of soil has an impact on the weight of fresh and dry crowns, the number of leaves, the chlorophyll content in the leaves, the volume of roots, and the height of the plant. The best type of soil is regusol soil. Plant height, root volume, fresh and dry crown weight, and leaf chlorophyll content are all affected by POME concentration. The concentration of POME 450 ml/polybag showed the best results.

Mixed application of raw amino acid powder and Trichoderma harzianum fertilizer for the prevention and management of apple replant disease

Apple replant disease (ARD) is mainly caused by biological factors, and it severely restricts the development of the apple industry. The use of biological control measures to alleviate ARD is critically important for the sustainable development of the apple industry. The effects of raw amino acid powder and Trichoderma harzianum fertilizer on plant biomass, leaf and root indexes, soil physical and chemical properties, soil enzyme activity, and the soil fungal community were studied under pot and field conditions using Malus hupehensis Rehd. seedlings and grafted trees (Fuji New 2001/M9T337) as experimental materials. We found that the application of the materials significantly promoted plant growth, increased the leaf photosynthesis and chlorophyll content, root respiration rate, root antioxidant enzyme activity, and soil enzyme activity, significantly decreased the number of Fusarium sp. in soil, and significantly increased the abundance of beneficial bacteria. In conclusion, the mixed application of raw amino acid powder and Trichoderma harzianum fertilizer can is an effective method for the prevention and management of ARD.

Screening of saline-alkali tolerant microorganisms and their promoting effects on rice growth under saline-alkali stress

Soil salinization poses a global challenge, and cultivating rice on saline-alkali lands is a recognized strategy for exploiting and ameliorating these challenging environments, however, the yield and quality of rice are significantly lower compared to cultivation on non-saline lands. This study focused on the utilization of saline-alkali tolerant plant-growth-promoting microorganisms (PGPRs) and organic matter. Four PGPR strains were identified and subsequently fermented and propagated, and then combined in equal proportions and mixed with cow manure compost to prepare a PGPR amendment. This amendment was applied to rice cultivated in pots under saline-alkali stress. Agronomic traits were monitored at various growth stages to assess the amendment's impact on rice development. The results showed that under moderate saline-alkali stress, PGPR amendments significantly improved the physicochemical indicators of rice. Compared with the control group, rice plant height, root length and chlorophyll content increased by 113.56%, 43.19% and 95.43%, respectively. The antioxidant enzyme increased by 39.86%, and the levels of soluble sugars and proteins increased by 20.91% and 27.28%, respectively. Notably, rice under moderate saline-alkali stress showed greater improvements in response to the amendment compared to rice under mild stress conditions. These findings suggest that the amendments effectively mitigate the adverse effects of saline-alkali stress on rice growth, thereby offering a viable strategy for enhancing crop productivity in affected areas.