Stimulate Plant Growth Research Articles

Comprehensive analysis of nano-fertilizers in Indian agriculture - A review

This is a comprehensive review of studies of nano-fertilizers for their efficacy in stimulating plant growth, facilitating higher nutrient uptake and thus enhancing overall crop yield and productivity. The intricate insights into the mechanisms through which nano-fertilizers ensure sustained nutrient release, optimize nutrient absorption and augment nutrient utilization efficiency, have been reviewed. Several scientific studies indicate the potential of nanotechnology to enhance crop performance in terms of better crop growth and higher productivity. Regarding the economic implications of adopting nano-fertilizers, several findings indicate that nano-fertilizers could offer cost advantages over conventional fertilizers, potentially alleviating the government's subsidy burden and reducing import expenses on huge quantities of major commercial fertilizers. This comprehensive review also explores the challenges faced by Indian agriculture in crop production and the potential of nanotechnology to revolutionize productivity on a sustainable basis. The study emphasizes the urgent need for enhanced and sustained crop production and highlights the significance of nano-fertilizer application as an innovative and environmentally friendly solution. In conclusion, this comprehensive overview of the status of stagnant crop production in India identifies the challenges in augmenting productivity and proposes nanotechnology-based fertilizers and their utility in major agricultural crops cultivation as a promising solution. The findings underscore the need for further research and the widespread adoption of nanotechnology-based fertilizers in Indian agriculture to ensure sustainable and enhanced production and productivity.

A plant-derived biostimulant Aminolom Enzimatico® application stimulates chlorophyll content, electrolyte leakage, stomata density and root yield of radishes under salinity stress.

Biostimulants stimulate plant growth and tolerance to salinity stress, which creates unfavorable conditions for plant growth from emergence to harvest; however, little is known about their roles in triggering salt tolerance. Therefore, the study aimed to determine how applying a foliar plant-derived biostimulant (Aminolom Enzimatico® 24%) affects the growth (leaf area, biomass weight, root diameter, root fresh weight, and water-soluble dry matter), physiology (chlorophyll content, electrolyte leakage, cell membrane stability, and relative water content), and stomata of the lower and upper parts of leaves in radish plants (Raphanus sativus L.) under salinity stress. Radish plantlets at 7 d old were irrigated with saline water (i.e., 50, 100, 150, and 200 mM NaCl), and the biostimulant was sprayed twice at 7 d intervals. Under salinity stress, increased water-soluble dry matter content was detected, along with reduced plant biomass weight, root fresh weight, and root diameter. Meanwhile, the foliar biostimulant increased the mean root fresh weight, biomass fresh weight, and leaf area by 12%, 13.6%, and 24% compared to the control, respectively. Increasing NaCl dramatically reduced leaf area and relative water content, whereas chlorophyll content and stomata densities on both sides of the leaves improved. By regulating physiological parameters and thereby promoting root and leaf growth, the biostimulant application improved the radish plants' tolerance to salinity stress up to 100 mM NaCl. Spraying the biostimulant can also boost plant growth, root yield, and radish quality under moderate salinity stress.

Cocultivos de microorganismos endófitos: Estrategia para la producción de bioestimulantes y compuestos de valor agregado

Cocultures between algae and bacteria aim to harness the metabolic capabilities of both microorganisms for biotechnological purposes. However, establishing a successful coculture is challenging because of their different nutritional and environmental requirements. This work proposes the establishment of a coculture between the plant growth-promoting bacterium Methylobacterium oryzae and the unicellular green alga Coccomyxa simplex, both endophytes of Vachellia farnesiana, with the aim of using their metabolic capacities to produce value-added compounds. To achieve this, the conditions to obtain a stable alga-bacteria coculture were defined, and the effect of the coculture and the initial nutrient concentration on lipid and pigment production, as well as plant growth stimulation were evaluated. A stable coculture was successfully established enabling the growth of both microorganisms even in the absence of carbon and nitrogen sources. The coculture stimulated lipid production (up to 43%) and pigment production (by 2.5 to 4.8 times). Additionally, the coculture's supernatant improved the growth of radish seedlings, suggesting that the coculture promotes the production of biostimulant compounds with potential to enhance crop yields and reduce the use of chemical fertilizers.

Influence of Rhodococcus qingshengii VKM Ac-2784D biostimulator on bacterial isolates from potato endo- and rhizosphere

The potato microbiome has a significant impact on plant growth and development. In order to affect this microbiome, agriculture can use various biopreparations on the basis of soil microorganisms. Being vulnerable to pathogens and drought, potato plants are particularly useful in the development of biopreparations. Special attention is given to Rhodococcus bacteria due to their ability to clean contaminated soil and stimulate plant growth. The present study was aimed at examining the effect of Rhodococcus qingshengii VKM Ac-2784D on bacteria isolated from potato endo- and rhizosphere. It is known that only a small fraction of microorganisms within the plant microbiome can be obtained in pure culture. Given these limitations, it was possible to isolate over 70 endophytic strains without the use of selective media and show that many of them are sensitive to the presence of a biopreparation component on the basis of Rhodococcus qingshengii VKM Ac-2784D. The metagenomic study indicates a change in the composition of the microbial community following treatment with the biopreparation. The experiments also show that the bacteria remain sensitive to Rhodococcus even in the presence of other competing strains. In general, the study results indicate a modulating effect of the biopreparation on the potato microbiome without phytotoxicity. The findings are important for understanding the effect of the biopreparation on the microbial composition of soil and potato plants, as well as for developing effective strategies for the use of microorganisms in agriculture.

Potential of plant growth promoting rhizobacteria for enhancement of tomato growth

AbstractPlant growth‐promoting rhizobacteria (PGPR) associated with roots produce several biomolecules that stimulate plant growth. The study aimed to assess the potential of PGPR for tomato (Solanum lycopersicum L.) growth enhancement. Three PGPR isolates (Pseudomonas isolates PIA2 and PIA3, and Bacillus isolate BIA1) were evaluated for growth promotion under greenhouse conditions. The experiment was conducted in three replications using Maya and Melkesalsa tomato varieties in a completely randomized design. Treatment with BIA1 resulted in the highest fresh weights of shoots (29.05 g) and roots (3.72 g) for the Maya variety (TC1) and 28.69 and 2.76 g for the Melkesalsa variety (TC2), respectively. Treatment with PIA2 showed maximum fresh weights of the shoots (25.05 g) and roots (3.26 g) for the TC2. Tomato plants treated with BIA1 and PIA2 exhibited significant increases in height, by 40.1% and 22.6% in the TC1 and 45.2% and 27.6% in the TC2, respectively. Besides, treatments with BIA1 and PIA2 in the TC1 increased the dry weight of shoots by 46.6% and 30.2% and that of roots by 73.3% and 68.7%, respectively. For the TC2, BIA1 and PIA2 isolates increased the dry weight of roots by 54.9% and 34.4% and that of roots by 68.1% and 48.9%, respectively. The results generally showed that BIA1 and PIA2 could be used to foster plant growth. Further study under field the conditions of BIA1 and PIA2 are highly recommended.

Bacillus cabrialesii subsp. cabrialesii Strain TE5: A Promising Biological Control Bacterium Against the Causal Agent of Spot Blotch in Wheat.

Strain TE5 was isolated from a wheat (Triticum turgidum L. subsp. durum) rhizosphere grown in a commercial field of wheat in the Yaqui Valley in Mexico. In this work, we present strain TE5 as a promising biological control agent against Bipolaris sorokiniana. First, after its genome sequencing through Illumina NovaSeq, this strain showed a genome size of 4,262,927 bp, with a 43.74% G + C content, an N50 value of 397,059 bp, an L50 value of 4 bp, and 41 contigs (>500 bp). Taxonomical affiliation was carried out by using overall genome relatedness indexes (OGRIs) and the construction of a phylogenomic tree based on the whole genome. The results indicated that strain TE5 identifies with Bacillus cabrialesii subsp. cabrialesii. Genomic annotation using Rapid Annotation Using Subsystems Technology (RAST) and Rapid Prokaryotic Genome Annotation (Prokka) indicated the presence of 4615 coding DNA sequences (CDSs) distributed across 330 subsystems, which included gene families associated with biocontrol, stress response, and iron competition. Furthermore, when the antiSMASH 7.1 platform was used for genome mining, the results indicated the presence of seven putative biosynthetic gene clusters related to the production of biocontrol metabolites, namely subtilosin A, bacillibactin, fengycin, bacillaene, bacilysin, surfactin, and rhizocticin A. Moreover, the antifungal activity of strain TE5 and its cell-free extract (CFE) was evaluated against Bipolaris sorokiniana, an emergent wheat pathogen. The results of in vitro dual confrontation showed fungal growth inhibition of 67% by strain TE5. Additionally, its CFE almost completely inhibited (93%) the growth of the studied phytopathogenic fungus on liquid media. Further observations of the impact of these bacterial metabolites on fungal spore germination exhibited inhibition of fungal spores through degrading the germinative hypha, avoiding mycelium development. Finally, the protective effect of strain TE5 against Bipolaris sorokiniana was evaluated for wheat seedlings. The results showed a significant decrease (83%) in disease severity in comparison with the plant infection without inoculation of the biological control agent. Thus, this work proposes Bacillus cabrialesii subsp. cabrialesii strain TE5 as a promising biological control agent against the wheat pathogen Bipolaris sorokiniana while suggesting lipopeptides as the potential mode of action, together with plant growth and defense stimulation.

Whole-genome sequencing and secondary metabolite exploration of the novel Bacillus velezensis BN with broad-spectrum antagonistic activity against fungal plant pathogens.

The utilization of chemical pesticides recovers 30%-40% of food losses. However, their application has also triggered a series of problems, including food safety, environmental pollution, pesticide resistance, and incidents of poisoning. Consequently, green pesticides are increasingly seen as viable alternatives to their chemical counterparts. Among these, Plant Growth-Promoting Rhizobacteria (PGPR), which are found within plant rhizosphere, stand out for their capacity to stimulate plant growth. Recently, we isolated a strain, BN, with broad-spectrum antimicrobial activity from the rhizosphere of Lilium brownii. Identification revealed that this strain belongs to the species Bacillus velezensis and exhibits significant inhibitory effects against various fungal plant pathogens. The complete genome sequence of B. velezensis BN consists of a circular chromosome with a length of 3,929,791 bp, includes 3,747 protein-coding genes, 81 small RNAs, 27 rRNAs, and 86 tRNAs. Genomic analysis revealed that 29% of the genes are directly involved in plant growth, while 70% of the genes are indirectly involved. In addition, 12 putative biosynthetic gene clusters were identified, responsible for the synthesis of secondary metabolites, such as non-ribosomal peptides, lanthipeptides, polyketides, siderophores, and terpenes. These findings provide a scientific basis for the development of efficient antimicrobial agents and the construction of biopesticide production platforms in chassis cells.

Estimulantes de crescimento no tratamento de sementes e adubação foliar em melancia

ABSTRACT Plant growth stimulants are a promising technology for agriculture to improve plant growth. These stimulants are often derived from a blend of plant regulators, minerals, amino acids, and other substances tested on various plants. The objective of this study was to evaluate the effects of a growth stimulant (micronutrients and amino acids) for seed treatment and foliar application on the initial growth of watermelon (Citrullus lanatus; cultivar Crimson Sweet). A randomized block experimental design with four replications was used, in a 6×2 factorial arrangement consisted of six growth stimulant rates (0, 1, 2, 3, 4, and 5 mL kg-1) for seed treatment, combined or not with foliar application of the same growth stimulant at 300 mL ha-1 26 days after sowing. The plant characteristics evaluated were: number of leaves per plant; shoot, root, and total plant lengths (cm); and shoot, root, and total dry weights. The use of the growth stimulant rate of 4 mL kg-1 for treating watermelon seeds, combined with foliar application of the growth stimulant (300 mL ha-1 26 days after sowing), provided the best growth conditions to the plants, which was shown by their higher number of leaves, shoot length, and shoot and total dry weights.

Preparation of lignosulphonate nanoparticles and their applications in dye removal and as plant growth stimulators

Preparation of lignosulphonate nanoparticles and their applications in dye removal and as plant growth stimulators

Impact of organomineral fertilizers-ameliorants based on natural aluminosilicates and biologically active substances on a corn growth. Part 1

This paper studies the impact of expanded vermiculite, humic substances and organomineral ameliorant fertilizers obtained by immobilizing humic substances on expanded vermiculite on the growth of corn plants. Immobilization of humic substances on natural aluminosilicates, such as expanded vermiculite allows achieving a synergistic effect combining the ameliorative properties of expanded vermiculite, which improves soil structure and water-holding capacity with the fertilizing properties of humic substances, stimulating plant growth and increasing their resistance to stress. In addition, the use of this organomineral ameliorant-fertilizer of prolonged action helps maintain soil fertility for a long time due to the gradual release of nutrients and improvement of the agrochemical characteristics of the soil. Indicators of total biomass, root and aboveground part mass, number and mass of green leaves, as well as morphometric parameters such as plant height and stem thickness were considered in laboratory experiments. The obtained results demonstrate a significant improvement in plant growth when using the developed ameliorant fertilizers under conditions of moisture deficiency and highly depleted soils. According to the results of the experiment, the total biomass with roots increased by 57.3 % when using expanded vermiculite and by 80.7% when adding humic substances. The use of the ameliorant fertilizer "GumiVer" (soil : GumiVer/9 : 1) increased the biomass by 127.6 % compared to the control, which confirms the synergistic effect between the components of the ameliorant fertilizer. The increase in the mass of the aboveground part and the mass of roots when using the ameliorant fertilizer "GumiVer" was 135.8 and 107.3 %, respectively.

ВЛИЯНИЕ ФОСФОРИСТОЙ КИСЛОТЫ НА ФУНГИЦИДНУЮ АКТИВНОСТЬ КАРБЕНДАЗИМА И ТЕБУКОНАЗОЛА

Fungicidal compositions have been developed for dressing of seeds and protecting crops of cultivated plants from phytopathogenic fungi. Fungicidal compositions as active ingredients contain methyl ester of 2 benzimidazolylcarbamic acid (BMC, carbendazim) and phosphorous acid in a mass ratio of 3 : (1-1.5), respectively, and tebuconazole with phosphorous acid in a mass ratio of 1 : (1-5). The formulation is in the form of a flowable suspension paste. The fungicidal activity of the fungicides on wheat seedlings was studied and field tests were carried out. The proposed fungicidal compositions have a synergistic effect, which reduces the consumption rates of active substances, reduces the fungicidal load on the environment, stimulates plant growth, and increases the yield of grain crops.

ПОЛУЧЕНИЯ ПЕРСПЕКТИВНЫХ ШТАММОВ ИЗ ДИКОРАСТУЩИХ РАСТЕНИЙ ДЛЯ ПРИМЕНЕНИЯ В СЕЛЬСКОМ ХОЗЯЙСТВЕ

The studies were conducted to create new consortia of microorganisms obtained from wild plant species (hypericum, oregano, plantain and reed) and to test their ability to be maintained in the soil and rhizosphere. The properties of 216 bacterial isolates that are important for protecting and stimulating plant growth, both in laboratory and field conditions, were determined, namely, enzymatic activity, including phytase, protease, lipase, nitrogenase, cellulase and amylase. In addition, the antagonistic activity of the isolates to the phytopathogenic fungus Fusarium oxysporum was tested. Then isolates were identified by comparing the 16S rRNA gene sequences. Pathogenic bacteria were then screened out and the most promising bacterial isolates were selected based on their enzymatic activities, from which a consortium was assembled to test the possibility of its maintenance in the soil and rhizosphere of Universiade wheat plants. For this purpose, the seeds were treated with the consortium at a dose of ×107 CFU/ml in a 1% carboxymethylcellulose solution and the soil and roots of the control and test plants were washed after 14 days. The presence or absence of the strains under study was determined by polymerase chain reaction fingerprinting. The consortium of microorganisms was better preserved in the soil than on the roots of plants. Its use increased the shoot length of experimental plants, relative to the control, by 38.6% (from 10.6 cm to 14.7 cm), the length of the root system by 22.1% (from 12.2 cm to 14.9 cm) and seed germination by 3.0% (from 87% to 90%). The obtained data can be used for further experiments and practical application in agriculture.

Growth-Promoting Effects of Grass Root-Derived Fungi Cadophora fastigiata, Paraphoma fimeti and Plectosphaerella cucumerina on Spring Barley (Hordeum vulgare) and Italian Ryegrass (Lolium multiflorum).

Many endophytic fungi are approved as plant growth stimulants, and several commercial biostimulants have already been introduced in agricultural practice. However, there are still many species of fungi whose plant growth-promoting properties have been understudied or not studied at all. We examined the growth-promoting effect in spring barley (Hordeum vulgare) and Italian ryegrass (Lolium multiflorum) induced by three endophytic fungi previously obtained from the roots of Festuca/Lolium grasses. Surface-sterilized seeds were inoculated with a spore suspension of Cadophora fastigiata (isolate BSG003), Paraphoma fimeti (BSG010), Plectosphaerella cucumerina (BSG006), and their spore mixture. Before harvesting, the inoculated plants were grown in a greenhouse, with the barley being in multi-cavity trays for 30 days and ryegrass being placed in an original cylindric element system for 63 days. All three newly tested fungi had a positive effect on the growth of the barley and ryegrass plants, with the most pronounced impact observed in their root size. The fungal inoculations increased the dry shoot biomass between 11% and 26% in Italian ryegrass, but no such impact was observed in barley. The highest root increment was observed in barley. Herein, P. cucumerina and C. fastigiata inoculations were superior to other treatments, showing an increase in root dry weight of 50% compared to 20%, respectively. All fungal inoculations significantly promoted root growth in Italian ryegrass, resulting in a 20-30% increase in dry weight compared to non-inoculated plants. Moreover, a strong stimulatory effect of the fungi-emitted VOCs on the root development was observed in plate-in-plate arrays. In the presence of C. fastigiata and P. cucumerina cultures, the number of roots and root hairs in barley seedlings doubled compared to control plants. Thus, in our study, we demonstrated the potential of the grass root-derived endophytes C. fastigiata, P. fimeti, and P. cucumerina as growth promoters for spring barley and Italian ryegrass. These studies can be extended to other major crops and grasses by evaluating different fungal isolates.

INTERACTIVE IMPACT OF THE SPECTRAL COMPOSITION OF ADDITIONAL LIGHTING AND ROOT ZONE TEMPERATURE ON THE PRODUCTIVITY OF HYDROPONIC LETTUCE

Hydroponic lettuce production in greenhouses is becoming increasingly popular in Ukraine. However, there is a lack of research evaluating the impact of light spectra, root zone temperature, production systems, and lettuce varieties on yield. This study aims to determine the interactive effects of nighttime supplemental lighting, nutrient solution temperature, and production system on the growth and productivity of various lettuce varieties under suboptimal air temperatures typical for winter greenhouses. The study used three lighting regimes: no lighting (control), violet LEDs (spectrum R90:G0:B10), and warm white LEDs (spectrum R35:G42:B23). Two nutrient solution temperatures—12.6 °C (no heating) and 18.8 °C (with heating)—as well as two production systems—Nutrient Film Technique (NFT) and Constant Flood Table (CFT)—were applied for lettuce cultivation. Red and green lettuce varieties of four types were studied: leafy, heading, oakleaf, and romaine. The results showed that the absence of supplemental lighting and heating significantly reduced yield, while their combination positively influenced the dry mass of shoots. The highest productivity was achieved with the CFT system, especially when combined with violet LEDs, which had a higher red light component that stimulates plant growth. It was found that violet lighting significantly outperformed white LEDs, particularly when the nutrient solution was heated. The most sensitive lettuce varieties to root zone conditions and lighting were Adriana, Cedar, Red Sails, and Salvia. In particular, under violet LEDs, these varieties showed the highest productivity when the CFT system was used. This research suggests effective strategies for optimizing hydroponic lettuce cultivation in winter greenhouse conditions in Ukraine. The findings can be useful for farmers aiming to increase yield and product quality, as well as for optimizing costs under conditions of limited resources.

Synthesis and Degradation of the Phytohormone Indole-3-Acetic Acid by the Versatile Bacterium Paraburkholderia xenovorans LB400 and Its Growth Promotion of Nicotiana tabacum Plant.

Plant growth-promoting bacteria (PGPB) play a role in stimulating plant growth through mechanisms such as the synthesis of the phytohormone indole-3-acetic acid (IAA). The aims of this study were the characterization of IAA synthesis and degradation by the model aromatic-degrading bacterium Paraburkholderia xenovorans LB400, and its growth promotion of the Nicotiana tabacum plant. Strain LB400 was able to synthesize IAA (measured by HPLC) during growth in the presence of tryptophan and at least one additional carbon source; synthesis of anthranilic acid was also observed. RT-PCR analysis indicates that under these conditions, strain LB400 expressed the ipdC gene, which encodes indole-3-pyruvate decarboxylase, suggesting that IAA biosynthesis proceeds through the indole-3-pyruvate pathway. In addition, strain LB400 degraded IAA and grew on IAA as a sole carbon and energy source. Strain LB400 expressed the iacC and catA genes, which encode the α subunit of the aromatic-ring-hydroxylating dioxygenase in the IAA catabolic pathway and the catechol 1,2-dioxygenase, respectively, which may suggest a peripheral IAA pathway leading to the central catechol pathway. Notably, P. xenovorans LB400 promoted the growth of tobacco seedlings, increasing the number and the length of the roots. In conclusion, this study indicates that the versatile bacterium P. xenovorans LB400 is a PGPB.

BC204, a citrus‐based plant extract, stimulates plant growth in Arabidopsis thaliana and Solanum lycopersicum through regulation and signaling

AbstractBC204 is a citrus‐based plant extract applied as a plant biostimulant on a variety of plant species in South Africa, China, and Australia. Although there are reports that it elicits physiological responses such as an increase in crop yield, abiotic and biotic stress tolerance, and fruit quality, no molecular data are available to explain the specific mechanisms underlying these effects. In this study, an RNA sequencing approach was adopted to elucidate the effects of BC204 at the molecular level in Arabidopsis thaliana and Solanum lycopersicum. BC204, applied via either a 0.01% (v/v) soil drench to A. thaliana or a 0.05% (v/v) foliar spray to S. lycopersicum, stimulated above‐ground biomass production whilst eliciting a large change in gene expression levels across several primary and secondary biochemical pathways in shoot tissues. Of the entire transcriptomic profile examined, 8.212% of genes were significantly differentially expressed between the treated and control groups in A. thaliana and 18.059% of genes for S. lycopersicum. Most notably, genes involved in photosynthesis, several aspects of cell wall biogenesis, remodeling and restructuring, carbohydrate metabolism, signaling, stress, and secondary metabolism were upregulated, which could explain the observed increase in plant growth. Little correlation in types of gene and pathway induction was observed between the two model organisms. Genes related to transcription and RNA regulation were both strongly up‐ and downregulated, which suggests that BC204 plays a role in inducing and suppressing several pathways. This novel study provides valuable information to be used as a starting point for targeted future research and identifying new targets for enhanced plant growth and vigor.

Isolation and characterization of plant growth stimulating bacteria Serratia marcescens from the microbial community of Huanglongbing (HLB) escape citrus trees in Punjab, Pakistan

Beneficial bacteria play a crucial role in combating Huanglongbing (HLB) disease, a global concern for the citrus industry around the globe. To explore the role of beneficial bacteria and enhance the productivity and sustainability of citrus against HLB disease, the bacteria associated with citrus were investigated. Samples were collected from HLB diseased, symptomatic, and asymptomatic citrus trees from Sargodha, a citrus growing region of Pakistan. Plant growth-stimulating bacteria isolated and characterized from the rhizosphere of citrus were identified as Serratia marcescens KRED strain, based on their phenotypic features, biochemical nature, and 16S rRNA sequence analysis. Out of twenty samples, KRED was identified in four samples of HLB asymptomatic trees while no strain of KRED was identified in symptomatic trees. Bacterial isolates possessing plant-beneficial properties were dominant species among the isolated PGPBs. The isolated bacteria were studied for their plant growth-promoting traits like IAA production, nitrogen fixation ability, siderophore production and ­lactose fermentation. Serratia marcescens exhibits plant growth promotion ability, but its specific interaction with HLB disease is not explored. In this context, the findings of this study underscore the importance of beneficial bacteria from the citrus rhizosphere and innovative approaches in the fight against HLB in citrus plants.

COMPOST PRODUCTION FROM MALAPARI SEED CAKE (Pongamia pinnata L.)

Biodiesel production from malapari (Pongamia pinnata L.) seed oil produces waste in the form of cake after extracting the oil from the seeds. Malapari seed cake needs to be processed to get added value. One form of processed malapari meal is in the form of composted organic fertilizer. Malapari cake can be used as compost because it contains minerals including potassium, sodium, calcium, zinc, iron, copper, manganese, phosphorus and sulfur which play a role in stimulating plant growth. Meanwhile, the nutrients contained in oil cake are nitrogen (3.2-3.7%), phosphorus (0.22-0.23%), and potassium (0.65-0.68%). This research aims to analyze the quality of compost from malapari seed cake produced according to SNI 19-7030-2004. This research was carried out in October-December 2023. The research location was at the Plant Physiology Laboratory, FMIPA and Soil Biology Laboratory, Faculty of Agriculture, Udayana University. Making compost consists of 4 treatments. The quantitative compost data obtained is presented in tabular form and compared with the requirements for compost from organic waste SNl 19-7030-2004. The results of the compost research showed that the compost from malapari seed cake had met the compost quality specifications according to SNI 19-7030-2004 for the parameters of water content, potassium and phosphorus, meanwhile, the parameters of pH, nitrogen, organic C, DHL (electrical conductivity), color and the smell does not meet the requirements.

Variability of secondary metabolism and morphogenesis of Ligustrum vulgare L. under different growing conditions in an urban environment

Abstract Assessing the condition of plants in an urban landscaping is a necessary component of monitoring urban ecosystems. Studying how the sensitivity of plants to stressful conditions and the influence of many factors on their growth and development is important for determining the suitability of using plants for urban improvement. The purpose of this study was to identify the impact of stress factors on the growth and development of Ligustrum vulgare L. (commonly called privet). The research was conducted in the city of Kyiv, where the plants are affected by significant vehicle traffic, intense insolation or excessive shade, and mechanical traumatization of plants due to plant trimming. Shoots of Ligustrum vulgare L. of different ages and under different growing conditions were used for the analysis. The research used methods of morphometry, chromatographic profiling of secondary metabolites, and statistical data processing. To analyze the morphogenesis of annual shoots, the Gaussian model was used, which accurately (R2 > 0.90) describes their growth processes. The model coefficients were used for a comparative assessment of the growth dynamics of Ligustrum vulgare L. shoots depending on the growing conditions and plant care. Correlation analysis also allowed for the identification of potential connections between the growth model coefficients and certain phenolic synthesis products. It was found that the plant trimming leads to an increase in the length of the shoots and accelerated growth of the side shoots. The obtained results may indicate that phenolic compounds, in particular chlorogenic acid, directly or indirectly affect the regulation of growth and development of shoots of Ligustrum vulgare L. in response to stress factors, such as mechanical injury. The content of chlorogenic acid positively correlates with the increase in the length of internodes, which indicates its possible role in morphogenesis. It has been established that the profiles of phenolic substances allow identification of Ligustrum plants at the species level. Principal component analysis (PCA) and cluster analyses showed that the phenolic profiles of plants depend on their growing conditions and the urban environment. The study confirms the importance of plant trimming for stimulating plant growth. The significant adaptation potential of Ligustrum vulgare L. plants confirmed the suitability of their use in urban environments.

Impact of gibberellic acid GA3, quantum dot biochar, and rhizosphere bacteria on fenugreek plant growth and stress responses under lead stress

Lead (Pb) is a stress that can cause problems with several aspects of a plant’s metabolism, potentially impeding the plant’s ability to grow and develop. The use of gibberellic acid (GA3), quantum dot biochar (QDBC), and rhizobacteria (RB) can be effective methods to overcome this problem. Gibberellic acid is a crucial plant hormone that regulates plant growth, cell division, tissue differentiation, flowering, photosynthesis, and transpiration rate. It also significantly impacts crop resilience to stress, affecting plant morphology, enzymatic activity, and physiology. Biochar, a soil supplement, enhances plant development soil health, and reduces stress effects. Due to its large surface area and porosity, it increases soil water-holding capacity, nutrient retention, and microbial activity. Quantum dots, semiconductor nanoparticles, have been proposed as a potential method to alleviate plant stress by acting as antioxidants, reducing oxidative stress, and controlling nutrient and growth regulators. Rhizobacteria, soil bacteria in plant roots, stimulate plant growth, nutrient absorption, and harvesting capacity. They produce phytohormones, increase mineral and nitrogen accessibility, and can induce systemic resistance (ISR), affecting plant defense. This study investigates the effects of combining GA3, QDBC, and RB as amendments to fenugreek, both with 500 Pb stress and without Pb stress. Treatments (control, 0.25 GA3mg/L-QDBC, 0.5 GA3mg/L-QDBC, 0.25 GA3mg/L-QDBC + RB, and 0.5 GA3mg/L-QDBC + RB) were applied in six replications using a completely randomized design. Results demonstrate that the combination of 0.5 GA3mg/L-QDBC + RB with 500 Pb stress led to significant enhancements in fenugreek shoot fresh weight (15.62%), root fresh weight (73.53%), shoot dry weight (24.00%), and root dry weight (36.53%) compared to the control. Additionally, there were notable improvements in chlorophyll a (57.23%), chlorophyll b (19.21%), and total chlorophyll (36.23%) compared to the control under Pb stress, also showing the potential of 0.5 GA3mg/L-QDBC + RB with 500 Pb stress. The study suggests that combining 0.5 GA3mg/L-QDBC + RB with 500 Pb stress can effectively mitigate Pb stress in fenugreek.