Shoot Growth Research Articles

The effect of growth regulator on growth rate of amorphopallus titanum

The Amorphophallus flower is one of the Endangered species, so there needs to be an effort to preserve breeding with a fast time, namely artificial vegetative. In addition, the a need for a growth hormone to accelerate the growth process so that the number is not extinct, namely growth regulators (ZPT). The purpose of this study was to breed A. titanum vegetatively supported with growth regulators (ZPT) to improve quality and growth rates. The method used is a completely randomized design (CRD), which is divided into 4 treatments namely A (coconut water), B (shallots), C (bamboo shoots), and D (control) with a total of 4 replications so that in this study there were 16 plants (polybags). The results showed that the natural growth regulator treatment of shallot extract gave the best results in the parameter of the number of shoots, while coconut water extract gave the best results in the parameters of shoot length and growth time. Based on the results, it can be concluded that the use of natural growth regulators from coconut water, shallots, and bamboo shoots affects the growth rate of Amorphophallus titanum.

Evaluation of Substrate Effects on the Acclimatization of Two Endangered Curcuma Species

Propagation is necessary for the conservation of threatened species. Curcuma aruna Maknoi & Saensouk and C. pitukii Maknoi, Saensouk, Rakarcha & Thammar. have been successfully propagated using tissue culture methods but two main obstacles to transplantation from in vitro to ex vitro are its low survival rate and its poor adaptability to the ex vitro environment. Therefore, this study examined the effects of different substrate composites on the acclimatization of C. aruna and C. pitukii plantlets from greenhouse conditions. The three treatments of sand, peat moss, and sand, black rice husk, and coconut coir (1:1:1 w/w) were used for acclimatization. Acclimatization of C. aruna and C. pitukii was successful when transplanted into peat moss with a 100% survival rate and higher shoot and leaf growth in comparison to other substrates. The high rates of growth and survival indicate that our work is contributing to the conservation of both Curcuma species and can be used as a model for the transplanting of other Curcuma species.

Use of water containing calcium sulfate and in the production of Caryocar brasiliense seedlings

There is a growing demand for seedlings of the pequi tree (Caryocar brasiliense Cambess.), a fruit tree native to the Cerrado biome, for establishing commercial orchards and restoring degraded areas. However, the high calcium (Ca) content commonly found in irrigation water used in nurseries can alter the substrate’s chemical properties and affect plant growth. This study aimed to evaluate the effects of different concentrations of calcium sulfate (CaSO4) in irrigation water and the use of bicarbonate calcium-rich (Ca(HCO3)2) well water on the growth and mineral nutrition of C. brasiliense seedlings. The experiment was installed in a randomized block design, with five treatments, plants cultivated in a greenhouse and irrigated with distilled water solutions containing 0, 144, 288, and 433 mg L−1 of CaSO4, along with an additional treatment using well water. Morphological and nutritional characteristics of the plants, as well as substrate fertility attributes, were assessed 180 days after the initiation of treatments. The results indicated that increasing CaSO4 concentrations and use well water enhanced shoot growth, improved substrate fertility and increased the concentrations and contents of phosphorus (P), calcium, and sulfur (S) in leaf and hypocotyl tissues. However, CaSO4 negatively impacted root and hypocotyl dry weight and well water a lower dry weight ratio. Based on the Dickson Quality Index (DQI), high-quality C. brasiliense seedlings were best produced with irrigation water containing no added CaSO4 (0 mg L−1). These findings underscore the importance of optimizing calcium levels in irrigation water to balance nutrient availability and seedling development.

PENINGKATAN KUALITAS BENIH KENTANG DI SUMATERA BARAT: INVESTIGASI TERMOTERAPI UNTUK ELIMINASI VIRUS PADA TUNAS KENTANG CINGKARIANG

Cingkariang potato is a superior local variety from West Sumatra, yet its productivity is often hindered by poor seed quality due to viral infections. This study evaluated the effectiveness of thermotherapy in eliminating viruses from Cingkariang potato shoots. The research design used factorial RAL with two factors, namely thermotherapy temperature (30°C and 35°C) and duration (5, 10, 15, and 20 days). Results showed that temperature significantly affected the number and height of shoots, while duration influenced shoot emergence. In virus infection tests, 30°C successfully eliminated PVX but not PVY, whereas 35°C eliminated both viruses, as indicated by the absence of morphological symptoms in indicator plants. Duration had no significant effect on virus elimination efficacy. This study recommends 35°C as the optimal thermotherapy protocol to improve Cingkariang potato seed quality.

Lotus tenuis in Association with Arbuscular Mycorrhizal Fungi Is More Tolerant to Partial Submergence than to High-Intensity Defoliation

This study aimed to investigate the effect of the association of Lotus tenuis with arbuscular mycorrhizal fungi (AMF) on its development under high defoliation intensity or partial submergence in a P-deficient soil of the Salado River Basin in a pot experiment. L. tenuis mycorrhizal plants showed higher tolerance to partial submergence (91%) than to high defoliation intensity (57%). Shoot biomass was the highest in mycorrhizal non-stressed and submerged plants (11.71 g and 12.06 g, respectively), and decreased by 38% in defoliated plants. Both stress conditions caused a negative effect on root growth of plants with or without AMF. High-intensity defoliation can be considered the most stressful scenario for mycorrhizal L. tenuis plants and AMF play a more marked role in P nutrition. Under submergence, AMF caused a net effect on L. tenuis growth, improving carbon and P resource distribution to sustain shoot growth and elongation. Root AMF colonization and nodulation decreased under submergence. High arbuscular colonization percentages were reached under both stress conditions, indicating that the symbiosis may be functional. L. tenuis roots can act as a reservoir of the fungal community under severe stress conditions, allowing the preservation of the AMF inoculum.

Unveiling nitrogen preferences in indica rice: a classification study of cultivars in South China.

Do indica rice cultivars prefer ammonium or nitrate? Understanding this preference is key to optimizing nitrogen use efficiency in rice production. Ammonium and nitrate are crucial for plant nitrogen nutrition, as rice cultivars exhibit varying preferences. However, few studies have classified ammonium and nitrate preferences within indica cultivars. For the first time, this study classifies indica rice cultivars based on their ammonium and nitrate preferences, revealing significant differences in biomass production under various nitrogen treatments. This study investigated the effects of ammonium-only nutrition (100:0), ammonium-nitrate mixed nutrition (75:25), and nitrate-only nutrition (0:100) on the maximum root length, shoot length, SPAD value, and biomass of 24 widely cultivated indica cultivars in South China. Compared to ammonium-only nutrition, a mixed ammonium-nitrate treatment significantly boosted root and shoot growth, while nitrate-only nutrition led to a decline in chlorophyll content. Compared with the 100:0 treatment, the maximum root length, shoot length, root dry weight, shoot dry weight, and total dry weight in the 75:25 treatment significantly increased by 29.85%, 4.11%, 7.65%, 1.71% and 3.03% (p < 0.01), respectively; and the SPAD value in the 0:100 treatment significantly decreased by 4.22% (p < 0.01). These results demonstrate distinct responses of rice cultivars to different nitrogen treatments. Through correlation, principal component, and cluster analyses, the rice cultivars were categorized into three types: ammonium-preferring type (APT), ammonium- and nitrate-preferring type (ANPT), and nitrate-preferring type (NPT). The APT, ANPT, and NPT showed the highest biomass in the 100:0, 75:25, and 0:100 treatments, respectively, with the biomass in the ANPT significantly exceeding that of the APT (p < 0.01). These insights provide a foundation for breeding high-yield indica rice, optimizing nitrogen fertilizer strategies, and improving nitrogen use efficiency in sustainable agriculture.

Biostimulant potential of three Chlorophyta and their consortium: application on tomato seeds

Biostimulants are a sustainable tool for enhancing crop productivity while reducing dependency on fertilizers. This study aims to investigate the biostimulant effect of algal cell extracts and spent growth media (supernatants post biomass separation) on tomato (Solanum lycopersicum L.) seeds. Both extracts and media were obtained from three chlorophytes (Tetradesmus obliquus, Chlamydomonas reinhardtii and Auxenochlorella protothecoides) and their microalgal consortium which were grown in replete standard medium. Additionally, the consortium was cultured in diluted digestate. Three concentrations of algal extract (0.05, 0.1, and 0.2 mg mL−1) and spent medium (10%, 50%, and 100%) were applied by seed priming. Results revealed concentration-dependent biostimulant effects, with the algal species contributing moderately to the observed variability. Seeds treated with 0.1 mg mL−1 algal extract or 50% spent medium achieved up to 100% germination compared to 86% when treated with water. Additionally, they exhibited significantly greater root and shoot growth, up to 40% longer than controls, despite a delay in germination. When treatments utilized T. obliquus extract or spent medium, the overall yields were the highest. Conversely, treatments utilizing extract or spent medium from the digestate grown-consortium resulted in the lowest yields, even below control levels. This highlights the critical role growth medium plays in determining the composition of algal biomass, which in turn affects the efficacy of biostimulants. The study underscores the potential of algal-derived biostimulants in enhancing seed germination and seedling development. It also emphasizes the critical role of selecting and optimizing growth media to fully harness the benefits of algae as biostimulants.

RD29A-IPT expression enhances drought tolerance in transgenic perennial ryegrass

Abstract Genetic improvement and the identification of drought-tolerant cultivars are crucial in perennial ryegrass (Lolium perenne L.) turfgrass to enhance germplasm reserves for molecular breeding and the development of sustainable landscapes in arid and semi-arid green spaces. Cytokinins (CKs) are plant hormones that regulate various physiological processes, including cell division, shoot growth, and leaf senescence, and also are known to regulate plant responses to drought stress. This study aimed to enhance drought tolerance in perennial ryegrass cultivars by utilizing the drought-inducible RD29A promoter to drive the expression of the IPT gene, which boosts cytokinin levels. The research also compared the performance of these transgenic plants with wild-type (WT) plants and local perennial ryegrass accessions under varying irrigation conditions. Results showed that certain transgenic plants and local accessions displayed higher drought tolerance based on turf quality, physiological, and biochemical characteristics. The expression of the IPT gene was confirmed in transgenic plants exposed to drought stress. Transgenic lines including GM24, GM12, GC8, GC6, NC12, NC14, NS14, and GC3 exhibited increased drought tolerance, maintaining higher levels of cytokinins in the leaves, improving water content, photosynthetic rate, and antioxidant activity while reducing damage indicators. Catalase and superoxide dismutase activities were more influential than peroxidase in drought adaptation and recovery. The efficiency of the RD29A promoter and the use of the UBQ10 intron in the IPT gene construct affected gene expression. Moreover, the significant genotypic variation among local accessions indicates opportunities for improving drought tolerance through targeted breeding in sensitive and moderately tolerant genotypes. Further research is recommended to investigate hormonal balance and osmoregulation in transgenic and wild-type plants under multiple stresses. Additionally, identifying candidate genes involved in drought tolerance, particularly in local ryegrass accessions, should be a focus for future studies.

Natural Variation in Potassium Deficiency Responses Among Arabidopsis thaliana Accessions.

Potassium (K) is a key nutrient essential for plant growth, and its deficiency induces various adaptative responses in plants; however, the mechanisms underlying these responses remain unclear. In the present study, we explored the natural variation in K deficiency responses among 100 naturally occurring accessions of Arabidopsis thaliana and then performed a genome-wide association study (GWAS) to identify the genetic loci associated with these responses. All 100 Arabidopsis accessions showed significant differences in several traits under K deficiency, including shoot and root growth, photosynthetic activity, and inorganic ion contents. The results indicated that the reduction in K+ content due to K deficiency was correlated more significantly with decreases in the number and total length of lateral roots than with decreases in primary root length and shoot growth. Furthermore, GWAS and subsequent analyses of relevant mutants and transgenic plants suggested that several genes, which have not yet been shown to play a role in the K deficiency response, are associated with the number and/or total length of lateral roots under K deficiency. The identified genes are ROH1, NF-YA3, MAA3, and AtDTX28, which encode an exocyst subunit EXO70A1 interacting protein, an NF-Y type transcription factor, a female gametophyte development-related protein, and a MATE efflux family protein, respectively. These findings provide new insights into the mechanisms underlying K deficiency responses.

A maize landrace introgression library reveals a negative effect of root-to-shoot ratio on water-use efficiency.

Novel sources of genetic variability for water-use efficiency (WUE) are needed in order to breed varieties more suitable to sustainable cropping systems. Here, a maize (Zea mays L.) introgression library of the landrace Gaspé Flint into the reference line B73 was characterized in high-throughput phenotyping platforms, both in well-watered and moderate water-deficit conditions, for water use, WUE, and root and shoot growth. Traits heritability ranged from 0.77 to 0.93. The introgression of Gaspé Flint chromosome segments into the B73 genome significantly altered several traits. Some introgression lines exhibited a faster shoot biomass accumulation than B73, resulting in higher WUE at the expense of root growth. Quantitative trait loci (QTL)mapping identified seven major QTL clusters affecting shoot growth and WUE, two of which overlapped, with opposite effects, with QTLs for root biomass known to include root developmental genes. These results support the non-intuitive hypothesis that reduced root-to-shoot ratio positively affects maize WUE.

Imbalance between boron and phosphorus supply influences boron deficiency symptoms in Brassica napus L.

The occurrence of boron (B) deficiency in Brassicaceae crops has increased in recent years. Inappropriate application of B with other nutrients often exacerbates symptoms of B deficiency. The aim of this study was to explore the interactive effects of B and phosphorus (P) on the B deficiency symptoms of rapeseed (Brassica napus L.). Two rapeseed cultivars ('W10' and 'ZS11') were treated with two B application rates (low and high B) and three P application rates (low, medium, and high P), and the growth parameters (root morphology, B absorption and distribution, and the P/B ratio) were examined in pot and hydroponic experiments. Under low B conditions, plants showed severely reduced root and shoot growth but it was greatly improved when supplemented with medium P supply. Further analysis revealed that high P combined with low B decreased the B concentration of newly initiated leaves and seeds, and increased the P/B ratio in plants compared with the medium P and low B combination, resulting in the aggravation of B deficiency of rapeseed. In comparison with the B-inefficient cultivar 'W10', the B-efficient cultivar 'ZS11' had superior growth and seed yield under low B conditions. Furthermore, 'W10' and 'ZS11' displayed significant differences in the response of the interaction between B and P to plant P/B ratio and root morphological parameters, which may reflect distinct genotype characteristics. The findings emphasize the importance of interactions between B and P in the growth and yield formation of rapeseed in B-deficient soils, as imbalanced B and P supply can exacerbate B deficiency symptoms in rapeseed. © 2025 Society of Chemical Industry.

Assembly and application of a synthetic bacterial community for enhancing barley tolerance to drought

Under climate change scenarios for temperate regions in Europe, prolonged droughts pose a major threat to barley production, but few studies have been conducted on stress mitigation strategies using plant-beneficial rhizobacteria. With this in mind, we isolated and screened a culture collection of drought-tolerant bacteria from the barley rhizosphere. From this collection, we assembled a 16-member consortium based on their relative abundances in the rhizosphere after drought and in vitro osmotic stress tolerance (Drought Tolerant Synthetic microbial Community/”DT-SynCom”). Members of the DT-SynCom range from Proteobacteria to Firmicutes and Actinobacteria. We used Oxford Nanopore and Illumina technologies to assemble complete genomes. Whole genome annotation revealed the presence of a number of genes associated with plant growth promoting traits such as IAA biosynthesis, ACC deaminase activity and siderophore production. In vitro assays confirmed auxin production, ACC deaminase activity, siderophore production, inorganic P solubilization, and cellulase and chitinase activities by the selected bacterial strains. The consortium members were not antagonistic to each other, and were either neutral or beneficial to barley shoot and root growth of barley when applied individually in vitro. To clarify the effect of the designed DT-SynCom on barley drought tolerance, a pot experiment was conducted under drought stress conditions. The DT-SynCom reduced the number of wilting leaves and had a positive effect on barley growth under drought. The results of the research suggest that the members of the barley DT-SynCom have beneficial plant growth promoting traits that result in improved plant growth under drought stress.

Foliar application of copper restores early pod yield without improvements in nitrogen nutrition and vegetative growth of soybean under low-copper stress

Although foliar copper (Cu) spray is widely adopted to correct nutrient deficiency, detailed evaluation of the effectiveness of fertilizer sources for this goal remains crucial. The interactive effect between root Cu supply and foliar application, as soluble sulfate (CuS) or sparingly soluble microparticulate oxide (CuO), on nodulation traits, plant nutritional status and dry mass of vegetative and reproductive organs was assessed. Plants were fertigated until full pod phase with Cu deficiency (0.01 µmol L−1 Cu, CuDef) or sufficiency (1.0 µmol L−1 Cu, CuSuf). These conditions were combined with nutrient spray (0.5 g L−1 Cu) at V4 phase as CuS or CuO in addition to a control with deionized water. Cu deficiency reduced dry mass and number of nodules, which was reflected in decreased leaf N concentration. While CuDef markedly reduced dry mass (−88%) and number of pods (−86%), the effect size on shoot biomass was 4.0-fold less pronounced. Cu concentration in sprayed leaves increased similarly with both fertilizer sources, while the response in the unsprayed organs was higher with CuS. Cu spray was able to reverse the negative effects of Cu deficiency on pod yield. However, nodulation traits, plant N nutrition and vegetative growth were not improved. The sensitivity of soybean yield formation to low Cu mostly relates to impairments on pod set rather on plant growth and N acquisition. Implications for grain yield of CuDef-plants, related to the lack of synchrony between improved pod set with the recovery of shoot growth and N nutrition under Cu spray, warrants elucidation.

Laboratory assessment of Lantana camara L. extracts for selective inhibition of rice weeds: phytotoxicity, crop response, and phenolic composition

Weeds significantly reduce rice (Oryza sativa L.) yield and grain quality, highlighting the need for sustainable weed management strategies. This study evaluated the bioherbicidal potential of methanolic extracts from Lantana camara L. (LC) against dominant rice field weeds Echinochloa crus-galli (BY), Leptochloa chinensis (RS), and Fimbristylis miliacea (GF), and examined the recovery responses of rice varieties OM18 and OM5451. At 0.48 g/mL, LC extract markedly suppressed shoot and root growth in RS, and GF, with root inhibition reaching 95.14–100%. BY was less sensitive, especially in shoot growth (24.21% inhibition). Interestingly, low concentrations (0.01–0.06 g/mL) promoted early rice growth, suggesting hormetic stimulation. IC90 values confirmed differential sensitivity: GF was most susceptible (0.129 g/mL), while BY was highly resistant (2.658 g/mL). OM5451 showed greater recovery after 168 h. HPLC analysis identified major phenolic compounds as veratric acid (5.605 µg/mL), p-coumaric acid (1.533 µg/mL), vanillic, salicylic, and gallic acids likely contributing to LC’s phytotoxicity. While the findings underscore that LC may be potent as a selective natural herbicide, this laboratory-based study remains exploratory. Field-scale validation, ecological impact assessments, and formulation refinement are essential next steps. Nevertheless, this work highlights LC’s dual role, as both an invasive species and a possible bioresource for eco-friendly weed control.

Induction of Organogenesis and Regeneration Species Tagetes erecta In Vitro

Marigold (Tagetes erecta) from the Asteraceae family is well-known for its various uses as cut flowers, potted plants, ornamental plants, medicines, dyes, and biopesticides. Micropropagation and optimization of in vitro regeneration of T.erecta species provide opportunities for plant propagation and utilization of biotechnology in plant breeding. This study evaluated the regeneration efficiency of in vitro plantlet leaf explants with different combinations of IAA and BAP concentrations in organogenesis induction media. IAA concentration affects the growth of adventitious shoots on explants. Decreasing IAA concentration affects the percentage of shoot growth, roots, and average number of roots in organogenesis induction media. Meanwhile, adding cytokinins to the induction media will modulate auxin movement during organogenesis and plant cell regeneration. Leaf explants on Murashige and Skoog (MS) media supplemented with 2.8 µM IAA + 31.0 µM BAP showed shoot growth reaching 58%, with root growth reaching 32%. Meanwhile, using lower BAP 2.8 µM IAA + 13.3 µM BAP resulted in 63% of explants forming shoots with a lower percentage of root growth. Increasing the concentration of IAA (5.7 µM + 13.3 µM BAP) showed a root formation response reaching 61% with a smaller number of shoots (48%). The explant response began with the explant part differentiating to form a callus with a growing point that would form yellowish-green shoots (RHS / Fan3-N144-C) at 28 days of induction

Impact of a horticultural mineral oil on bermudagrass performance under salinity stress

Abstract Rising salinity levels in both water and soil pose a pressing challenge for golf course managers throughout the United States. To address this issue, turfgrass managers seek effective products to improve plant health and reduce the impacts of salinity stress. The objective of this study was to evaluate the effects of a mineral oil product on salinity stress in bermudagrass [(Cynodon dactylon (L.) Pers. × Cynodon transvaalensis Burtt Davy), cv. Tifway]. The experiment was conducted in a controlled environment in Stillwater, OK, where bermudagrass was established from sprigs and grown in lysimeters filled with sand. The experimental design was a split‐plot, with irrigation salinity treatment as the main plot factor and the rate of horticultural mineral oil (Civitas Turf Defense Pre‐M1xed; Intelligro) as the sub‐plot factor. Irrigation salinity treatments included three electrical conductivity levels: 1.5, 15, and 30 dS m−1, and Civitas was applied every 2 weeks at rates of 0, 1.43, and 2.71 mL m−2. Over 8 weeks, Tifway bermudagrass was evaluated weekly in terms of turf quality, normalized difference vegetation index, vertical shoot growth, and percent green cover. At the end of the study, salt uptake was assessed by measuring the tissue sodium (Na+) concentration and Na+ excretion rate from leaf salt glands. Additionally, root biomass was measured. Results showed a decline in turfgrass performance and an increase in tissue Na⁺ concentration as salinity levels increased. Tifway maintained good quality at 15 dS m−1 for 8 weeks in sand, both without Civitas and with an application rate of 1.43 mL m−2. However, increasing the application to 2.71 mL m−2 consistently compromised turfgrass performance under 30 dS m−1 salinity stress, highlighting its adverse effects in highly saline conditions.

Effect of BAP and Picloram on Shoot Induction (&lt;i&gt;Musa acuminata&lt;/i&gt; Colla var. Mulu Bebek)

Musa acuminata Colla var. Mulu Bebek is a high-quality banana from Ternate, North Maluku. Its conventional cultivation faces challenges due to Fusarium wilt, reducing productivity. In vitro culture offers a solution for rapid, disease-free seedling production. This study aims to examine the effect of BAP and picloram on shoot induction using a CRFD at various concentrations (0–3 ppm) and evaluate the percentage of live explants, emergence time, and number and length of shoots and roots. Results show that 1 ppm picloram accelerates root emergence, while 0 ppm promotes the fastest shoot emergence, the longest shoot and root lengths. 1 ppm BAP increases shoot numbers. The interaction of picloram and BAP has a significant effect on the parameters of the fastest root emergence time, namely 1 ppm picloram + 0 ppm BAP, 1 ppm and 3 ppm, the fastest shoot emergence time, namely without the addition of PGR, and the longest shoot length, 0 ppm picloram + 2 ppm BAP. The combination of 0 ppm picloram + 1 ppm BAP is the optimal condition for a percentage of 100% live explants, the fastest time for root emergence, the highest number of shoots and roots, the longest shoot and root length and the optimal condition for the fastest time for shoot emergence is 0 picloram + 0 ppm BAP. This study provides insight into the role of BAP and picloram in inducing banana shoots that has not been reported before. The micropropagation media formula obtained in this study is an effort to improve the quality of healthy banana seedlings in the future.

Effect of Different Growing Media on Propagation of Croton variegatum Semi Hardwood Cuttings at Jhapa, Nepal

Codiaeum variegatum, commonly known as garden croton or variegated croton, is a member of the Euphorbiaceae family and is popular for its colorful ornamental foliage. An experiment was carried out at Gauradaha Agriculture Campus, Gauradaha, Jhapa, in 2024 to study the effect of different growing media on propagation of croton under partially shaded condition. Propagation through semi-hardwood cuttings is a common method, but success rates are often low due to inappropriate or suboptimal growing media. The aim of this study was to determine the effect of different media on root and shoot growth of croton. The experiment was laid out in Complete Randomized Design (CRD) with seven treatments and three replications. The treatments were soil (control), sand, sand and peatmoss (3:1), soil and perlite (1:1), mixture of sand, soil and perlite (1:1:1) and sand, soil and peatmoss (1:1:1). Different observations, root number and length, shoot number and shoot length, success percentage were recorded. Statistically superior result in root length (4.62 ± 0.15a), shoot number (4.80 ± 0.05a), shoot length (4.80 ± 0.05a) was observed in combination of soil + sand + peatmoss. However, root numbers were observed maximum in the treatment sand + peatmoss (10.40 ± 0.22a) at 35DAP, while soil and FYM showed lowest growth in terms of all factor through the period recorded. The combination of sand + soil + peatmoss (1:1:1) and soil + peatmoss (3:1) showed the highest success rate, which was 100%. Therefore, this research showed that combination of sand + soil + peatmoss was found to be best for the overall performance of croton plant propagated through semi hardwood cuttings in comparison to other media used in this research and is recommended in the tropic climatic condition of Jhapa.

Transcriptomic response of apple (Malus × domestica Borkh. cv. Húsvéti rozmaring) shoot explants to in vitro cultivation on media containing thidiazuron or 6-benzylaminopurine riboside

One of the most critical factors in maintaining healthy in vitro axillary apple shoot cultures is the cytokinin content of the medium. The effects of two cytokinins applied in the medium, thidiazuron and 6-benzylaminopurine riboside, each applied in a quantity of 4.5 µM, were studied on mRNA transcription of in vitro apple shoots. Transcriptomic response of in vitro apple shoots was investigated at two time points; at 48 h and 4 weeks (at the end of the subculture) after the cytokinin application by mRNA-seq, bioinformatics analysis, GO annotation and KEGG mapping. This study revealed that different expression intensities of DEGs were related to TF families (mainly WRKY, MYB, AP2/ERF, bHLH) associated with plant growth and development, in addition to enzymes involved in genetic and environmental information processing, cell motility, the zeatin biosynthesis, the tryptophan metabolism, the phenylpropanoid biosynthesis, and cutin, suberin, and wax biosynthesis. A putative roadmap based on changes in gene expression intensity that may be in association with various in vitro apple shoot development and growth disorders caused by different cytokinin supplies was conceived.

Role of Plant Growth Promoting Rhizobacteria for Advanced Sustainable Agricultural Practices: A Review

The role of PGPR in nutrient cycling, soil structure improvement, and soil pH modification. Traditional agriculture relies heavily on chemical inputs, which pose significant threats to the environment and deplete natural resources. The environmental challenges posed by chemical-based agriculture and emphasize the urgent need for sustainable alternatives in the face of climate change. Plant Growth-Promoting Rhizobacteria (PGPR) are beneficial soil microorganisms that enhance plant growth through various direct and indirect mechanisms, offering a sustainable approach to improving soil fertility and crop productivity. PGPR have emerged as a sustainable alternative, fostering plant development, and enhancing stress resilience. A comprehensive understanding of the underlying signalling pathways and stress management mechanisms is essential to maximizing their potential. Plant health has been demonstrated, nutrient uptake has improved, and environmental stress has been reduced with the help of PGPR. PGPR facilitate nitrogen fixation, phosphorus and potassium solubilization, and organic matter decomposition, enhancing nutrient availability and promoting plant growth. Their ability to produce exopolysaccharides contributes to soil aggregation, improving soil structure and water retention. Additionally, PGPR modifies rhizosphere pH, enhancing nutrient solubility and availability. PGPR also promote crop yield by enhancing root and shoot growth, improving seed germination, and increasing stress tolerance against drought, salinity, and heavy metal contamination. PGPR provides effective biocontrol against pathogens through antibiosis, competition, and induced systemic resistance (ISR), contributing to improved crop resilience. Despite their potential, several challenges hinder the widespread adoption of PGPR, including inconsistent field performance, limited shelf-life, compatibility issues with native soil microbiota, and regulatory barriers. Emerging approaches such as genetic engineering, multi-strain consortia, and nano-formulations are being developed to enhance PGPR efficacy and stability under diverse environmental conditions. Integrating PGPR with organic and chemical fertilizers presents a promising strategy for achieving higher yields while minimizing environmental impact. Research should focus on understanding PGPR-plant signalling pathways, optimizing formulation techniques, and developing policies to promote their commercial use. Collaborative efforts between researchers, industries, and policymakers are essential to enhance the application of PGPR in sustainable agriculture. Widespread adoption of PGPR-based technologies could significantly contribute to global food security, environmental sustainability, and the reduction of chemical inputs in agriculture. The potential of PGPR as a valuable tool for enhancing agricultural productivity through environmentally friendly practices. Future research should focus on developing efficient, cost-effective formulations and enhancing collaboration between researchers, policymakers, and industries to ensure global food security and environmental sustainability.