Search

Cultural association is widely practiced in rural areas by cashew nut producers. These producers typically cultivate annual plants between the rows of young cashew trees. However, there are interactions between these associated crops, which can either result in complementarity or competition among the plants for environmental resources such as water and nutrients. Consequently, young cashew seedlings newly planted were associated with groundnuts during their first two years. The aim of this study was to investigate the compatibility of the cashew/groundnut system. The results showed that there is competition between groundnuts and young cashew trees in the first year, leading to poor cashew growth in association. Nevertheless, from the second year onwards, cashew trees cultivated in association exhibited similar growth to those cultivated in monoculture. Therefore, it would be advisable to plant groundnut seeds sufficiently far from cashew tree seedlings to avoid potential competition in the first year of cultivation. [ABSTRACT FROM AUTHOR]

An individual's access to mates (i.e., its "mating potential") can constrain its reproduction but may also influence its fitness through effects on offspring survival. For instance, mate proximity may correspond with relatedness and lead to inbreeding depression in offspring. While offspring production and survival might respond differently to mating potential, previous studies have not considered the simultaneous effects of mating potential on these fitness components. We investigated the relationship of mating potential with both production and survival of offspring in populations of a long-lived herbaceous perennial, Echinacea angustifolia. Across 7 years and 14 sites, we quantified the mating potential of maternal plants in 1,278 mating bouts and followed the offspring from these bouts over 8 years. We used aster models to evaluate the relationship of mating potential with the number of offspring that emerged and that were alive after 8 years. Seedling emergence increased with mating potential. Despite this, the number of offspring surviving after 8 years showed no relationship to mating potential. Our results support the broader conclusion that the effect of mating potential on fitness erodes over time because of demographic stochasticity at the maternal level. [ABSTRACT FROM AUTHOR]

Seedling rot in sugar beet was observed at Snyder Farms, Wyoming, USA, in April 2022. The diseased seedlings exhibited water-soaked brown to blackish lesions in hypocotyls with poor root systems. Four fungal isolates were retrieved from the diseased samples, and their morphological features were found to be identical to those of previously reported Fusarium species. Artificial inoculation with isolates developed similar symptoms to those observed in the field samples. Based on morphological characteristics, pathogenicity assays, sequence homologies of the internal transcribed spacer, translation elongation factor (tef1α), largest subunit of RNA polymerase II (rpb2), β-tubulin (β-tub), and multilocus phylogenic analyses with tef1α and rpb2, the causal agent was identified as Fusarium clavum (F. incarnatum-equiseti species complex 5). This is the first worldwide report of sugar beet seedling rot caused by F. clavum, detected in Wyoming, USA. This finding will help to formulate effective management practices to manage the pathogen and prevent its widespread occurrence. [ABSTRACT FROM AUTHOR]

Monitoring the sanitary status of a large population of vegetative propagation materials is a challenge because it requires expensive and time-consuming testing. Here we report a group testing strategy to identify individual plants carrying viruses and/or a viroid in Pyrus betulifolia seedlings and virus-tested pear mother plants. First, the effect of pool size on RT-PCR detection of apple stem grooving virus (ASGV), apple stem pitting virus (ASPV), apple chlorotic leaf spot virus (ACLSV) and apple scar skin viroid (ASSVd) was evaluated; all of them could be sensitively detected in a bulk (pool) of eight samples. The virological condition of 2770 P. betulifolia seedlings and 110 virus-tested pear mother plants were then investigated by RT-PCR using a grouping strategy with 5 samples. We identified 20, 35 and 3 P. betulifolia seedlings as positive for ASGV, ASPV, and ASSVd, respectively, and 4 pear mother plants were identified as carrying ASGV. Our data indicated that RT-PCR testing on samples pooled before RNA extraction is a reliable and resource-efficient strategy to monitor the sanitary status of large numbers of pear vegetative propagation materials. The results presented here also highlight the possibility of pear seedling rootstocks being a source of viral infection. [ABSTRACT FROM AUTHOR]

Improvement of selenium (Se) uptake in fruit tree can improve the source of food Se for humans. In this study, the effect of various abscisic acid (ABA) concentrations on the Se uptake in Cyphomandra betacea Sendt. (Solanum betaceum Cav.) seedlings was studied under Se stress. Only the concentration of 20 μmol/L ABA promoted the growth of C. betacea seedlings by increasing the biomass and regulating the resistance physiology under Se stress. ABA also increased the Se content in C. betacea seedlings under Se stress. The concentration of ABA at 20 μmol/L got the maximum root Se and shoot Se contents, which increased by 76.64% and 55.83%, respectively, compared with the control. Correlation and grey relational analyses showed that the peroxidase activity and proline content had the first two closest relationship with the shoot Se content. This study shows that ABA can promote the Se uptake in C. betacea under Se stress, and the concentration of 20 μmol/L ABA is the optimum for Se uptake and growth of C. betacea. Under selenium (Se) stress, abscisic acid (ABA) promotes the Se uptake in Cyphomandra betacea Sendt. (Solanum betaceum Cav.) seedlings, but only the concentration of 20 μmol/L ABA promotes the growth of C. betacea seedlings. The shoot Se content is most closely correlated with the peroxidase activity and proline content. This study shows that ABA can promote the Se uptake in C. betacea under Se stress [ABSTRACT FROM AUTHOR]

Background: As the greenhouse effect intensifies, global temperatures are steadily increasing, posing a challenge to bread wheat (Triticum aestivum L.) production. It is imperative to comprehend the mechanism of high temperature tolerance in wheat and implement breeding programs to identify and develop heat-tolerant wheat germplasm and cultivars. Results: To identify quantitative trait loci (QTL) related to heat stress tolerance (HST) at seedling stage in wheat, a panel of 253 wheat accessions which were re-sequenced used to conduct genome-wide association studies (GWAS) using the factored spectrally transformed linear mixed models (FaST-LMM). For most accessions, the growth of seedlings was found to be inhibited under heat stress. Analysis of the phenotypic data revealed that under heat stress conditions, the main root length, total root length, and shoot length of seedlings decreased by 47.46%, 49.29%, and 15.19%, respectively, compared to those in normal conditions. However, 17 varieties were identified as heat stress tolerant germplasm. Through GWAS analysis, a total of 115 QTLs were detected under both heat stress and normal conditions. Furthermore, 15 stable QTL-clusters associated with heat response were identified. By combining gene expression, haplotype analysis, and gene annotation information within the physical intervals of the 15 QTL-clusters, two novel candidate genes, TraesCS4B03G0152700/TaWRKY74-B and TraesCS4B03G0501400/TaSnRK3.15-B, were responsive to temperature and identified as potential regulators of HST in wheat at the seedling stage. Conclusions: This study conducted a detailed genetic analysis and successfully identified two genes potentially associated with HST in wheat at the seedling stage, laying a foundation to further dissect the regulatory mechanism underlying HST in wheat under high temperature conditions. Our finding could serve as genomic landmarks for wheat breeding aimed at improving adaptation to heat stress in the face of climate change. [ABSTRACT FROM AUTHOR]

A fundamental challenge in the field of ecology involves understanding the adaptive traits and life history stages regulating the population dynamics of species across diverse habitats. Seed traits and early seedling vigor are thought to be key functional traits in plants, with important consequences for recruitment, establishment, and population persistence. However, little is known about how diverse seed traits interact with seed and microsite availability to impact plant populations. Here, we performed a factorial experiment involving seed addition and surface soil disturbance to explore the combined effects of seed and site availability using genotypes characterized by varying seed mass and dormancy traits. Additionally, we included hybrids that exhibited recombined seed trait relationships compared with natural genotypes, allowing us to assess the impact of specific seed traits on establishment across different sites. We detected a significant three-way interaction between seed addition, site conditions, and soil surface disturbance, influencing both seedling establishment and adult recruitment in Panicum hallii , a perennial grass found in coastal mesic (lowland) and inland xeric (upland) habitats. This establishment/recruitment pattern suggests that mesic and xeric establishment at foreign sites is constrained by the interplay of seed and site limitations. Notably, soil surface disturbance facilitated establishment and recruitment of the xeric genotype while limiting the mesic genotype across all sites. Our results highlight the importance of seed size and dormancy as key factors impacting seedling establishment and adult recruitment, suggesting a potential interactive relationship between these traits. [ABSTRACT FROM AUTHOR]

Background: The goal of this research is to enhance the quality of cucumber seedlings grown in greenhouses by experimenting with various soilless culture mediums (CMs) and the application of pistachio wood vinegar (WV). The experimental setup was designed as a factorial experiment within a randomized complete block design (RCBD), in greenhouse conditions featuring three replications to assess the effects of different culture media (CMs) and concentrations of pistachio wood vinegar (WV) on cucumber seedling growth. Cucumber seeds were planted in three CMs: coco peat-peat moss, coco peat-vermicompost, and date palm compost-vermicompost mixed in a 75:25 volume-to-volume ratio. These were then treated with pistachio WV at concentrations of 0, 0.5, and 1%, applied four times during irrigation following the emergence of the third leaf. Results: The study revealed that treating seedlings with 0.5% WV in the date palm compost-vermicompost CM significantly enhanced various growth parameters. Specifically, it resulted in a 90% increase in shoot fresh mass, a 59% increase in shoot dry mass, an 11% increase in root fresh mass, a 36% increase in root dry mass, a 65% increase in shoot length, a 62% increase in leaf area, a 25% increase in stem diameter, a 41% increase in relative water content (RWC), and a 6% improvement in membrane stability index (MSI), all in comparison to untreated seedlings grown in coco peat-peat moss CM. Furthermore, chlorophyll a, b, total chlorophyll, and carotenoid levels were 2.3, 2.7, 2.6, and 2.7 times higher, respectively, in seedlings treated with 0.5% WV and grown in the date palm compost-vermicompost CM, compared to those treated with the same concentration of WV but grown in coco peat-peat moss CM. Additionally, the Fv/Fm ratio saw a 52% increase. When plant nutrition was enhanced with the date palm compost-vermicompost CM and 1% WV, auxin content rose by 130% compared to seedlings grown in coco peat-peat moss CM and treated with 0.5% WV. Conclusions: The study demonstrates that using 0.5% WV in conjunction with date palm compost-vermicompost CM significantly betters the quality of cucumber seedlings, outperforming other treatment combinations. [ABSTRACT FROM AUTHOR]

Soybean is grown worldwide for its high protein and oil content. Weeds compete fiercely for resources, which affects soybean yields. Because of the progressive enhancement of weed resistance to herbicides and the quickly increasing cost of manual weeding, mechanical weed control is becoming the preferred method of weed control. Mechanical weed control finds it difficult to remove intra-row weeds due to the lack of rapid and precise weed/soybean detection and location technology. Rhodamine B (Rh-B) is a systemic crop compound that can be absorbed by soybeans which fluoresces under a specific excitation light. The purpose of this study is to combine systemic crop compounds and computer vision technology for the identification and localization of soybeans in the field. The fluorescence distribution properties of systemic crop compounds in soybeans and their effects on plant growth were explored. The fluorescence was mainly concentrated in soybean cotyledons treated with Rh-B. After a comparison of soybean seedlings treated with nine groups of rhodamine B solutions at different concentrations ranging from 0 to 1440 ppm, the soybeans treated with 180 ppm Rh-B for 24 h received the recommended dosage, resulting in significant fluorescence that did not affect crop growth. Increasing the Rh-B solutions reduced crop biomass, while prolonged treatment times reduced seed germination. The fluorescence produced lasted for 20 days, ensuring a stable signal in the early stages of growth. Additionally, a precise inter-row soybean plant location system based on a fluorescence imaging system with a 96.7% identification accuracy, determined on 300 datasets, was proposed. This article further confirms the potential of crop signaling technology to assist machines in achieving crop identification and localization in the field. [ABSTRACT FROM AUTHOR]

Background: In the context of early sowing of maize as a promising adaptation strategy that could significantly reduce the negative effects of climate change, an in-depth understanding of mechanisms underlying plant response to low-temperature stress is demanded. Although microRNAs (miRNAs) have been recognized as key regulators of plant stress response, research on their role in chilling tolerance of maize during early seedling stages is scarce. Therefore, it is of great significance to explore chilling-responsive miRNAs, reveal their expression patterns and associated target genes, as well as to examine the possible functions of the conserved and novel miRNAs. In this study, the role of miRNAs was examined in 5d-old maize seedlings of one tolerant and one sensitive inbred line exposed to chilling (10/8 °C) stress for 6 h and 24 h, by applying high throughput sequencing. Results: A total of 145 annotated known miRNAs belonging to 30 families and 876 potentially novel miRNAs were identified. Differential expression (DE) analysis between control and stress conditions identified 98 common miRNAs for both genotypes at one time point and eight miRNAs at both time points. Target prediction and enrichment analysis showed that the DE zma-miR396, zma-miR156, zma-miR319, and zma-miR159 miRNAs modulate growth and development. Furthermore, it was found that several other DE miRNAs were involved in abiotic stress response: antioxidative mechanisms (zma-miR398), signal transduction (zma-miR156, zma-miR167, zma-miR169) and regulation of water content (zma-miR164, zma-miR394, zma-miR396). The results underline the zma-miRNAs involvement in the modulation of their target genes expression as an important aspect of the plant's survival strategy and acclimation to chilling stress conditions. Conclusions: To our understanding, this is the first study on miRNAs in 5-d old seedlings' response to chilling stress, providing data on the role of known and novel miRNAs post-transcriptional regulation of expressed genes and contributing a possible platform for further network and functional analysis. [ABSTRACT FROM AUTHOR]

The use of mycorrhiza and seaweed are becoming significant and complementary applications in different production systems because organisms increased quality of seedlings and crop yield. This study has been conducted under growth chamber conditions to determine some of the seedling growth parameters (length (cm), stem diameter (mm), fresh weight (g plant −1), dry weight (g plant −1), root fresh weight (g plant −1), root dry weight (g plant −1), leaf area (cm2 plant−1), SPAD, photosynthesis rate (%) and color parameters). As a plant material, Cuma F1 and Mert F1 genotype seeds were sown. Endo Roots Soluble (Mycorrhiza (ERS)) and MC-Extra (Seaweed) were applied in different doses (0, 250 and 500 mg kg−1) to seedling growing vessels at a rate of 10 ml per plant. Treatment effects in tomato were found statistically significant (p ≤.01**) on stem diameter, fresh weight, dry weight. Seedling length, leaf area and SPAD results were also statistically significant (p ≤.01**), and the results of these parameters were higher in ERS. ERS increases the leaf area and SPAD measurements in tomato seedlings. The results of pepper measurements were found to be statistically significant at p ≤.05* on root fresh weight, SPAD and photosynthesis rate. The highest values of root fresh weight, SPAD were obtained from 250 mg kg−1 doses of ERS; the highest value of photosynthesis rate was measured from 500 mg kg−1 doses of ERS on pepper. The effect of 500 mg kg−1 ERS on seedling growth was found statistically significant in pepper. [ABSTRACT FROM AUTHOR]

Response of growth and morphology of Dracaena cambodiana seedlings, a rare and endangered plant, was studied by observing its response to five artificially controlled water supply levels. The results indicated that different levels of water supply significantly affected morphological indices and biomass. Except for specific leaf area, the ratio of leaf length to width and plant height, other indicators reached significant levels (P<0. 05). The allocation of biomass is mainly related to root traits, and there is no significant difference in chlorophyll and carotenoid content among different treatments in seedlings. According to the analysis, the seedlings could make full use of water to achieve rapid growth in the short and concentrated rainy season, and allocating more biomass to the root was good for the severe drought season after the rainy season. In summary, the seedlings of Dracaena cambodiana had strong ecological adaptability to the survival strategy of water response. [ABSTRACT FROM AUTHOR]

Water stress can adversely affect seed germination and plant growth. Seed osmopriming is a pre-sowing treatment in which seeds are soaked in osmotic solutions to undergo the first stage of germination prior to radicle protrusion. Seed osmopriming enhances germination performance under stressful environmental conditions, making it an effective method to improve plant resistance and yield. This study analyzed the effect of seed osmopriming with polyethylene glycol (PEG) on seed germination and physiological parameters of Coronilla varia L. Priming treatments using 10% to 30% PEG enhanced germination percentage, germination vigor, germination index, vitality index, and seedling mass and reduced the time to reach 50% germination (T50). The PEG concentration that led to better results was 10%. The content of soluble proteins (SP), proline (Pro), soluble sugars (SS), and malondialdehyde (MDA) in Coronilla varia L. seedlings increased with the severity of water stress. In addition, under water stress, electrolyte leakage rose, and peroxidase (POD) and superoxide dismutase (SOD) activities intensified, while catalase (CAT) activity increased at mild-to-moderate water stress but declined with more severe deficiency. The 10% PEG priming significantly improved germination percentage, germination vigor, germination index, vitality index, and time to 50% germination (T50) under water stress. Across the water stress gradient here tested (8 to 12% PEG), seed priming enhanced SP content, Pro content, and SOD activity in Coronilla varia L. seedlings compared to the unprimed treatments. Under 10% PEG-induced water stress, primed seedlings displayed a significantly lower MDA content and electrolyte leakage than their unprimed counterparts and exhibited significantly higher CAT and POD activities. However, under 12% PEG-induced water stress, differences in electrolyte leakage, CAT activity, and POD activity between primed and unprimed treatments were not significant. These findings suggest that PEG priming enhances the osmotic regulation and antioxidant capacity of Coronilla varia seedlings, facilitating seed germination and seedling growth and alleviating drought stress damage, albeit with reduced efficacy under severe water deficiency. [ABSTRACT FROM AUTHOR]

Background: Cadmium (Cd) pollution has declined crop yields and quality. Selenium (Se) is a beneficial mineral element that protects plants from oxidative damage, thereby improving crop tolerance to heavy metals. The molecular mechanism of Se-induced Cd tolerance in rice (Oryza sativa) is not yet understood. This study aimed to elucidate the beneficial mechanism of Se (1 mg/kg) in alleviating Cd toxicity in rice seedlings. Results: Exogenous selenium addition significantly improved the toxic effect of cadmium stress on rice seedlings, increasing plant height and fresh weight by 20.53% and 34.48%, respectively, and increasing chlorophyll and carotenoid content by 16.68% and 15.26%, respectively. Moreover, the MDA, ·OH, and protein carbonyl levels induced by cadmium stress were reduced by 47.65%, 67.57%, and 56.43%, respectively. Cell wall metabolism, energy cycling, and enzymatic and non-enzymatic antioxidant systems in rice seedlings were significantly enhanced. Transcriptome analysis showed that the expressions of key functional genes psbQ, psbO, psaG, psaD, atpG, and PetH were significantly up-regulated under low-concentration Se treatment, which enhanced the energy metabolism process of photosystem I and photosystem II in rice seedlings. At the same time, the up-regulation of LHCA, LHCB family, and C4H1, PRX, and atp6 functional genes improved the ability of photon capture and heavy metal ion binding in plants. Combined with proteome analysis, the expression of functional proteins OsGSTF1, OsGSTU11, OsG6PDH4, OsDHAB1, CP29, and CabE was significantly up-regulated under Se, which enhanced photosynthesis and anti-oxidative stress mechanism in rice seedlings. At the same time, it regulates the plant hormone signal transduction pathway. It up-regulates the expression response process of IAA, ABA, and JAZ to activate the synergistic effect between each cell rapidly and jointly maintain the homeostasis balance. Conclusion: Our results revealed the regulation process of Se-mediated critical metabolic pathways, functional genes, and proteins in rice under cadmium stress. They provided insights into the expression rules and dynamic response process of the Se-mediated plant resistance mechanism. This study provided the theoretical basis and technical support for crop safety in cropland ecosystems and cadmium-contaminated areas. Highlights: Se could improve the growth inhibition of rice under Cd stress. Se mediated the increase of photosynthetic pigment content. Se up-regulates functional genes and proteins involved in the photosynthetic system. Se-mediated decreased the content of MDA, ·OH, and protein carbonyl. Se-mediated plant hormone signal transduction plays a vital role in Cd detoxification. [ABSTRACT FROM AUTHOR]

Climate change, which causes periods with relatively high temperatures in winter in Poland, can lead to a shortening or interruption of the cold hardening of crops. Previous research indicates that cold acclimation is of key importance in the process of acquiring cereal tolerance to stress factors. The objective of this work was to verify the hypothesis that both natural temperature fluctuations and the plant genotype influence the content of metabolites as well as proteins, including antioxidant enzymes and photosystem proteins. The research material involved four winter triticale genotypes, differing in their tolerance to stress under controlled conditions. The values of chlorophyll a fluorescence parameters and antioxidant activity were measured in their seedlings. Subsequently, the contribution of selected proteins was verified using specific antibodies. In parallel, the profiling of the contents of chlorophylls, carotenoids, phenolic compounds, and proteins was carried out by Raman spectroscopy. The obtained results indicate that a better PSII performance along with a higher photosystem II proteins content and thioredoxin reductase abundance were accompanied by a higher antioxidant activity in the field-grown triticale seedlings. The Raman studies showed that the cold hardening led to a variation in photosynthetic dyes and an increase in the phenolic to carotenoids ratio in all DH lines. [ABSTRACT FROM AUTHOR]

This study conducted an activation experiment on tap water using a self‐designed dielectric barrier discharge plasma field. Aged pepper seeds and seedlings were chosen as the investigation's subjects to assess plasma‐activated water (PAW's) effects on aged seed germination, seedling growth, and their respective qualities. PAW cultivation led to notable improvements in pepper seeds' germination potential and rate, with increases of 18.0% and 28.3%, respectively. Moreover, the vitality index exhibited a remarkable rise of 250.0%. Concurrently, seedlings treated with PAW exhibited significant growth enhancements, with root length, root number, stem length, and leaf area increasing by 138.6%, 69.2%, 47.9%, and 28.4 cm², respectively. Additionally, PAW treatment induces changes in endogenous substances and enzyme activities in seeds and seedlings. [ABSTRACT FROM AUTHOR]

Management of alien invasive species is an essential action necessary to help reverse biodiversity loss. Here, we measure the effectiveness of brush piles constructed from invasive alien plant material to suppress the growth of invasive plant seedlings. We found invasive seedling recruitment was fully suppressed in brush pile plots compared to control plots due to suboptimal growth light and temperature conditions created by the piles. Further, brush piles supported 2‐fold to +7‐fold more animals than control plots. This method offers a promising solution for restoration practitioners' need for accessible, low‐cost management intervention for the on‐site disposal of removed plant biomass, which we demonstrated can also enhance native wildlife abundance. [ABSTRACT FROM AUTHOR]

We analyzed the biochemical compounds by GCMS and did bioassay of leaf extracts of five tree species viz., Aegle marmellos (L.) Correa, Annona squamosa L., Mangifera indica L., Morinda tinctoria Roxb and Moringa oleifera Lam. on germination and associated characteristics of kodomillet (Paspalum scrobiculatum L) and prosomillet (Panicum miliaceum L.). Response Index was used for comparison, and by GCMS, the compounds found in the leaves were determined and studied their effects on germination and seedling growth. The 5 % Moringa oleifera leaf extract, followed by extracts from A. squamosa and Mangifera indica, improved millets' seed germination. Perhaps because the extracts contained the dominant compounds 2- Piperidinone and 2-Pyrrolidinone. Tree leaf extracts from the above-donor species had a synergistic effects in prosomillet, stimulating germination by 14-18 %, than kodomillet. However, Morinda tinctoria and Aegle marmellos leaf extracts inhibited the germination of both millets than control. [ABSTRACT FROM AUTHOR]

In February 2021, damping off and collar and root rot on coriander (Coriandrum sativum L.) became widespread in the municipality of Vitória da Conquista, Bahia, Brazil. An oomycete was isolated from root and collar segments of affected seedlings and caused the same symptoms in inoculated seedlings. Based on morphological features and DNA sequences from the ITS and cox2 region, the pathogen was identified as Pythium aphanidermatum. To the best of our knowledge, this is the first report of the occurrence of P. aphanidermatum on coriander plants in Brazil. [ABSTRACT FROM AUTHOR]

This study characterizes seedling exudates of peas, tomatoes, and cucumbers at the level of chemical composition and functionality. A plant experiment confirmed that Rhizobium leguminosarum bv. viciae 3841 enhanced growth of pea shoots, while Azospirillum brasilense Sp7 supported growth of pea, tomato, and cucumber roots. Chemical analysis of exudates after 1 day of seedling incubation in water yielded differences between the exudates of the three plants. Most remarkably, cucumber seedling exudate did not contain detectable sugars. All exudates contained amino acids, nucleobases/nucleosides, and organic acids, among other compounds. Cucumber seedling exudate contained reduced glutathione. Migration on semi solid agar plates containing individual exudate compounds as putative chemoattractants revealed that R. leguminosarum bv. viciae was more selective than A. brasilense, which migrated towards any of the compounds tested. Migration on semi solid agar plates containing 1:1 dilutions of seedling exudate was observed for each of the combinations of bacteria and exudates tested. Likewise, R. leguminosarum bv. viciae and A. brasilense grew on each of the three seedling exudates, though at varying growth rates. We conclude that the seedling exudates of peas, tomatoes, and cucumbers contain everything that is needed for their symbiotic bacteria to migrate and grow on. [ABSTRACT FROM AUTHOR]

Drought has a direct impact on rice growth performance at various stages. Nevertheless, the impact of nanoparticles on the rice seedlings under drought stress remained limited. Thus, a laboratory experiment was conducted to investigate the effects of different concentrations (300, 600, and 900 mg/L) of silica nanoparticles (SiNPs) on morpho-histological and biochemical features of two rice varieties (UMT-R and MR219) under drought stress (15 % PEG). The findings indicated a substantial reduction due to drought stress in the growth, protein, and antioxidant enzymes, while increasing the proline, malondialdehyde (MDA), and hydrogen peroxide (H 2 O 2) content, and negatively affecting the root histology. Results showed that SiNPs at 600 mg/L were managed to improve plant growth, root vigour, and enzymatic antioxidant levels. Under SiNPs treated plants, among UMT-R and MR219, the proline (1.947 and 1.748 in leaves, 2.010 and 1.890 U/mg protein in roots), peroxidase (POD) (2.850 and 3.512 in leaves, 2.521 and 2.952 U/mg protein in roots), superoxide dismutase (SOD) (3.958 and 4.558 in leaves, 4.296 and 4.606 U/mg protein in roots), and catalase (CAT) (2.171 and 2.289 in leaves, 1.897 and 2.050 U/mg protein in roots) were higher than the drought stress conditions. Meanwhile, the nonenzymatic antioxidant, MDA (0.974 and 0.812 in leaves, 0.842 and 0.778 U/mg Protein in roots), and H 2 O 2 (1.378 and 1.229 in leaves, 1.280 and 1.054 U/mg Protein in roots) showed an opposite trend. SiNPs application noticeably enhanced the histological features of roots under drought conditions. The current findings suggested that SiNPs at 600 mg/L can mitigate the adverse impacts of drought stress and enhance the plant's resistance. Further study should be carried out on the reproductive stage and post-harvest performance of drought-stress rice treated with SiNPs. [Display omitted] • SiNPs treatment significantly increased plant growth under drought conditions. • SiNPs have a significant effect on the root histological traits. • SiNPs significantly enhance protein, proline, SOD, POD, and CAT content. • UMT-R was more sensitive to drought stress as compared to MR219. [ABSTRACT FROM AUTHOR]

In light of the environmental pollution resulting from the excessive use of chemical fertilizers, several methods, including the analysis of morphological and cultural characteristics as well as ITS rDNA sequencing, were utilized to identify the strain and evaluate its phosphate solubilizing capacity. A controlled greenhouse pot experiment was then conducted to assess the effects of the phosphate solubilizing bacteria strain Y-5 on crop growth and soil fertility. The identification results revealed that the phosphate solubilizing strain, Y-5, belongs to Pseudomonas donghuensis. Under liquid culture for 5 days, the ratio of the phosphate solubilizing ring's diameter to the colony's diameter (D/d) was 3.51. Notably, strain Y-5 exhibited exceptional phosphate solubilization efficiency, with a maximum phosphate solubilizing amount of calcium phosphate reaching 432.25 mg/L. Furthermore, the highest phosphate soluble content of lecithin was 116.37 mg/L, highlighting its robust phosphate solubilizing capacity. The pot experiment results revealed that the modified biochar of strain Y-5 effectively enhances the content of available phosphate and organic matter in soil. Additionally, the modified biochar of the Y-5 strain exerted a significant growth-promoting effect on corn seedlings. Based on the indices of maize seedling growth and soil property changes, it was determined that the optimal application ratio of Pseudomonas donghuensis modified biochar was approximately 10 g/kg. This research result significantly reduced the cost of popularizing and applying phosphate solubilizing bacteria modified biochar and served as a new agricultural material with good prospects for popularization and application, potentially contributing to the green and sustainable development of agriculture in the future. [ABSTRACT FROM AUTHOR]

Salt stress causes deleterious impacts on the germination, growth, and productivity of various crop plants. Screening new cultivars regarding salt stress tolerance could enhance the growth and productivity of sorghum. In this regard, an experiment was conducted at the laboratory of the Department of Agronomy, Hajee Mohamad Danesh Science and Technology University (HSTU), Bangladesh, in October 2018 to find out salt tolerance based on seed germination and seedling growth traits. The experiment consisted of seven sorghum varieties, viz. Adan Gab, Karmici, Debuday, ESP/S01, Green Jambuplus, Jambo, and Elmi Jama, and three levels of salt stress, viz. 0, 100, and 200 mM NaClinduced salt stress, laid out completely randomized design (CRD) with three replications. The seeds of the seven sorghum varieties were placed in plastic trays (20 cm x 10 cm) on a sand bed irrigated with tap water (control) and NaCl (100 and 200 mM salinity levels) solutions. Data were collected on germination character and seedling growth at parameters. The collected data were analyzed statistically and means were adjudged by DMRT at 1 and 5% level of probability. The results of the experiment revealed that salinity stress significantly reduced the germination percentage (GP) and germination rate (GR) of sorghum in all sorghum varieties, and the variety Debuday showed the highest values of GP and GR, while Karmici showed the lowest values under 100 and 200 NaCl stress. Moreover, the root and shoot lengths, fresh weights, and dry weights gradually decreased with salinity levels, and the minimum reduction was recorded in Debuday, whereas the maximum reduction was in the Karmici variety. Higher Na and lower K accumulation of the Debuday genotype can be treated as salt tolerant. Contrary, the salt tolerance index (STI) based on the root and shoot dry weight in the Debuday variety exhibited the highest values, and the Karmici variety exhibited the minimum values under salt stresses. The inhibition of GP and GR, and lengths and biomass weight of root and shoot, were at the minimum level, while, on the contrary, the values declined superficially in the Karmici variety. Therefore, it can be concluded that the variety Debuday is indorsed as a salt-tolerant sorghum variety, and Karmici is a more susceptible one, based on the seed germination and seedling growth properties. [ABSTRACT FROM AUTHOR]

The aim of the present study was to assess the selectivity of herbicides applied in the pre and post-planting of pre-sprouted seedlings (PSS). The experiment was conducted in a greenhouse, using a completely randomized design, with nine treatments and four repetitions. The IACSP95-5000 cultivar was used. The treatments consisted of herbicides applied in five doses as follows: in pre-planting: sulfentrazone, diclosulam, imazapic, and imazapyr, in post-planting: ethoxysulfuron, halosulfuron, 2,4-D and MSMA, and a control treatment without herbicide. Injury symptoms were assessed at 7, 15, 30, 45, 60, 75, and 90 days after application (DAA), height, diameter, number of tillers, chlorophyll A, B, and total chlorophyll at 30, 60, and 90 DAA, leaf area, shoot and root dry mass at 90 DAA. The post-emergent herbicides were considered selective. Pre-planting herbicides reduced the variables assessed at 90 DAA, observed by linear regression for diclosulam and imazapic, and exponential regression for imazapyr. Treatments with sulfentrazone caused few injury symptoms, with subsequent recovery. In addition, all the variables analyzed were equal to control, with the sulfentrazone considered selective for the IACSP95-5000 cultivar. [ABSTRACT FROM AUTHOR]

Our experiments explored the effects of far-red (FR) light on cucumber (Cucumis sativus L. 'Zhongnong No. 26') seedling growth. Our results indicated that FR light significantly promoted the growth of cucumber seedlings. Specifically, it promoted the accumulation of shoot biomass and the elongation of internodes and leaves (except the first leaf at the bottom). Further analysis showed that FR light had no effect on the accumulation contents of abscisic acid (ABA) and auxin (IAA) in seedling leaves. Still, it significantly caused the increase of the gibberellin (GA3, GA4, and GA7) contents and the decrease of GA1 content, which suggested that the leaf expansion progress under FR light may be primarily related to GA. Therefore, the cucumber seedling leaf expansion response to GA was evaluated under different light sources. The exogenous spraying of different GA4/7 contents significantly promoted the leaf expansion of cucumber seedlings under white light, while the GA biosynthesis inhibitor paclobutrazol (PAC) significantly promoted the expression of GA hydrolytic genes (GA2ox2 and GA2ox4) and decreased the content of endogenous active GA, which inhibited the leaf expansion induced by FR light. As expected, the combination of exogenous GA4/7 and PAC restored the growth promotion effect of FR light on cucumber seedling leaves. It increased the contents of endogenous active GA (GA1, GA3, GA4, and GA7), and the expression trend in GA synthetic/hydrolytic-related genes was the opposite of that of PAC was applied alone. All of the above results indicated that FR light regulates leaf expansion progress in cucumber seedlings through GA. [ABSTRACT FROM AUTHOR]

Among the several factors limiting sugarcane production, the occurrence and severity of diseases such as orange rust is one of the reason for replacing cultivars and the use of silicon (Si) can reduce the intensity of diseases caused by pathogens. This study was carried out to evaluate the effect of a preventive application of Si to suppress the intensity of orange rust caused by Puccinia kuehnii on sugarcane seedlings. Three experiments under house conditions have been conducted using a Randomized Block Design with two in a 2x5 factorial scheme (soil with and without Si application x five foliar treatments), with variety RB92-579 and SP81-3250, and a third study with 13 treatments (soil and foliar treatments) with variety SP-015503. RB92-579 showed higher dry mass without Si application in the soil whereas higher levels of Si content in plants and soil with soil treated with Si was verified. Foliar treatments showed higher values of height, dry mass, and Si uptake. The severity level of orange rust on SP81-3250 with soil treated with Si was lower than on untreated soil. SP-015503 showed a dry mass and Si uptake increase with foliar treatments, especially with silicic acid. K silicate and silicic acid showed lower severity of orange rust than the control and fungicide. Si was able to reduce the severity of orange rust and improve plant development even though it does not have effectiveness as a preventive treatment to control orange rust in one of the studied varieties. [ABSTRACT FROM AUTHOR]

Ascochyta blight and Fusarium root rot are the most serious fungal diseases of pea, caused by D. pinodes and F. avenaceum, respectively. Due to the lack of fully resistant cultivars, we proposed the use of biologically synthesized silver nanoparticles (bio-AgNPs) as a novel protecting agent. In this study, we evaluated the antifungal properties and effectiveness of bio-AgNPs, in in vitro (poisoned food technique; resazurin assay) and in vivo (seedlings infection) experiments, against D. pinodes and F. avenaceum. Moreover, the effects of diseases on changes in the seedlings' metabolic profiles were analyzed. The MIC for spores of both fungi was 125 mg/L, and bio-AgNPs at 200 mg/L most effectively inhibited the mycelium growth of D. pinodes and F. avenaceum (by 45 and 26%, respectively, measured on the 14th day of incubation). The treatment of seedlings with bio-AgNPs or fungicides before inoculation prevented the development of infection. Bio-AgNPs at concentrations of 200 mg/L for D. pinodes and 100 mg/L for F. avenaceum effectively inhibited infections' spread. The comparison of changes in polar metabolites' profiles revealed disturbances in carbon and nitrogen metabolism in pea seedlings by both pathogenic fungi. The involvement of bio-AgNPs in the mobilization of plant metabolism in response to fungal infection is also discussed. [ABSTRACT FROM AUTHOR]

Allelopathy is the chemical interactions between plants that might lead to either stimulation or inhibition of growth, community structure, and plant invasions. Lantana camara L. is a noxious invasive weed that negatively affects seed germination, seedling growth, and increases the mortality of the crop plant. The objective of this work was to assess allelopathic effect of L. camara leaf aqueous extract on germination and seedling growth of Capsicum annuum (pepper) and Daucus carota (carrot). The aqueous extract of Lantana leaf samples was used as a source of allelopathic effects. Data were collected for germination and seedling growth parameters. The result indicated that the highest concentration of the allelopathic extract (20 mg/L) has demonstrated significantly the highest germination inhibition rate GIR (60.00%), germination speed V (2.54 U/day) for D. carota as GIR (70.00%), mean germination time MGT (0.36 days), and GI (0.67%) for C. annuum seeds. The highest concentration of the allelopathic extract (20 mg/L) has recorded the highest plumule inhibition rate PIR (59.63%) and radical inhibition rate RIR (48.95%) for D. carota seeds, as well as PIR (27.47%) and RLR (79.49%) for C. annuum. The largest negative allelopathic index (−60.00% or allelopathic intensity of 60.00%) was recorded for D. carota seeds, whilst (−63.43% or allelopathic intensity of 63.43%) was recorded for C. annuum seed germination. For D. carota seed germination, the first principal component (PC1) has got high positive loads from GI (0.36), RLR (0.31), GR (0.34), allelopathic index AI (0.34), relative length of plumule RLP (0.24), and V (0.30). By contrast, PC1 for D. carota seed germination has got the highest negative component loads recorded by GIR (−0.34), PIR (−0.24), MGT (−0.35), and RIR (−0.31). In allelopathic effect on C. annum seed germination, the first principal component (PC1) has got high positive scores from relative length of radical RLR (0.31), RLP (0.33), germination rate GR (0.33), V (0.33), and AI (0.33). Likewise, the high negative component loads were recorded by GIR (−0.33), PIR (−0.33), RIR (−0.31), and MGT (−0.32). The result of the present study demonstrated that GIR, PIR, and RIR were directly related to negative allelopathic activity. [ABSTRACT FROM AUTHOR]

Using Cinnamomum saxatile as the material, a four-factor and four-level orthogonal design was adopted to explore the effects of proportional fertilization of N, P, K, Ca on the growth of one-year-old C. saxatile seedlings. The purpose of the study was to provide scientific basis for fertilization of C. saxatile. The results showed that the diameter and height of C. saxatile increased in general when the application time of N, P, K and Ca fertilizers was 30-150 d. The average value was 1. 11-1. 61 times and 1. 23-2. 17 times than the first fertilization. The effects of different fertilization treatments on the diameter and height of C. saxatile seedlings were significantly different. The best performance of growth was the combination of T8(N1P3K2Ca1 ). The effect of N fertilizer on the diameter and height of C. saxatile seedlings was significant, but the effect of P and K fertilizer was not. The effect of Ca fertilizer on height was significant, but not on diameter. The diameter growth reached the maximum at N1(100 mg / plant N) level. In conclusion, N1P3K2Ca1(100 mg / plant N+80 mg / plant P+40 mg / plant K)was the most suitable fertilizer combination to promote the growth of C. saxatile seedlings under the study conditions. [ABSTRACT FROM AUTHOR]

Seed germination is an important development process in plant growth. The phytohormone abscisic acid (ABA) plays a critical role during seed germination. However, the mechanism of rapeseed in response to ABA is still elusive. In order to understand changes of rapeseed under exogenous ABA treatment, we explored differentially expressed metabolites (DEMs) and the differentially expressed genes (DEGs) between mock- and ABA-treated seedlings. A widely targeted LC-MS/MS based metabolomics were used to identify and quantify metabolic changes in response to ABA during seed germination, and a total of 186 significantly DEMs were identified. There are many compounds which are involved in ABA stimuli, especially some specific ABA transportation-related metabolites such as starches and lipids were screened out. Meanwhile, a total of 4440 significantly DEGs were identified by transcriptomic analyses. There was a significant enrichment of DEGs related to phenylpropanoid and cell wall organization. It suggests that exogenous ABA mainly affects seed germination by regulating cell wall loosening. Finally, the correlation analysis of the key DEMs and DEGs indicates that many DEGs play a direct or indirect regulatory role in DEMs metabolism. The integrative analysis between DEGs and DEMs suggests that the starch and sucrose pathways were the key pathway in ABA responses. The two metabolites from starch and sucrose pathways, levan and cellobiose, both were found significantly down-regulated in ABA-treated seedlings. These comprehensive metabolic and transcript analyses provide useful information for the subsequent post-transcriptional modification and post germination growth of rapeseed in response to ABA signals and stresses. [ABSTRACT FROM AUTHOR]

This study was carried out to develop a protocol for the biomass production and cultivation of Ulva ohnoi using germling clusters. The zygote germination was evaluated under different density conditions (10, 20, 30, and 40 × 104 gametes mL−1), nutrients (4, 8, and 16 mL L−1 of von Stosch standard solution), and irradiance (100, 200, and 300 μmol photons m−2 s−1). Afterwards, the formed germling clusters were cultivated in two pulse-fed treatments, one with nutrients offered once and the other on a daily basis, to establish a growth curve and evaluate the limiting factors. Once the optimal conditions for the cultivation were established, they will be evaluated for mature fronds based on the growth rate and productivity. Irradiance was the main factor that affected germling development. Moreover, the nutrient concentration did not present differences in their development. Germling clusters, at low densities had a significantly higher growth rate. Nutrient treatments with 8 mL L−1 was sufficient for the growth of germling clusters. The maximum cultivation period under the conditions tested was four days and thereafter the nutrients and density become limiting, and the renewal of the culture medium, harvest, and return to the initial density is recommended. Germling clusters are preferable over adult fronds, as they showed more significantly stable growth rates and yields, while adult fronds started to reproduce causing reduced growth and productivity. [ABSTRACT FROM AUTHOR]

Like all life forms, plants suffer from high levels of mercury (Hg), known as one of the most harmful heavy metals in soil. The present study was performed to explore the effects of exogenous nitric oxide (NO) on Hg toxicity in maize (Zea mays L., cv. Arifiye-2) seedlings. Plants were grown in a hydroponic system containing 1/2 diluted Hoagland at 16 h day length, 25/20 °C (day/night) and 60% relative humidity. Eight day-old maize seedlings were first treated with NO (as 0.1 µM sodium nitroprusside) and then they were exposed to Hg toxicity (as 100 µM HgCl2) after 24 h. The toxic Hg decreased seedling growth, chlorophyll content, proline content, calcium and manganese contents, nonenzymatic antioxidant contents, cell membrane viscosity, and antioxidant enzyme activities (superoxide dismutase, catalase, peroxidases, and glutathione reductase) while it increased the generation of reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) and super oxide anion (O2.-), and lipid peroxidation (as malondialdehyde, MDA) content and the amount of sodium ion (Na+) in the seedlings. However, NO treatment markedly enhanced the growth parameters (dry and fresh weight, and plant height) and manganese and potassium contents as well as contents of antioxidants and chlorophyll thus alleviating the negative effects caused by the Hg stress. Also, it decreased the generation of ROS and lipid peroxidation level by activating the antioxidant enzymes. These results show that NO in maize seedlings under Hg toxicity may improve stress response and mitigate oxidative stress by stimulating the antioxidant system and modulating ion homeostasis. [ABSTRACT FROM AUTHOR]

Investigating the effects of priming methods on seedling physiology under osmotic stress conditions is important to understand how priming enhances osmotic stress tolerance in safflower. The mechanisms by which priming achieves this at the physiological level, such as changes in osmoprotectants, antioxidants, and membrane damage, are not well understood. This research aims to fill these knowledge gaps and provide insights that can be used to optimize priming treatments and improve safflower productivity in drought-prone areas.. Seeds were treated with priming including distilled water, folic acid, glutathione, epibrassinolide and chitosan and then subjected to osmotic stresses including no osmotic stress, mild osmotic stress (4 bar) and severe osmotic stress (8 bar) for germination and seedling growth. Severe osmotic stress increased soluble leaf proteins, this increase was observed in all priming treatments except distilled water. Severe osmotic stress increased soluble leaf proteins by an average of 35% in folic acid, chitosan, and epibrassinolide treatments. Chitosan treatment exhibited 172% and 188% more proline under mild and severe stress, respectively, compared to the control. Folic acid treatment showed a 207% increase in catalase under severe stress. Epibrassinolide and glutathione treatments had 201% more superoxide dismutase (SOD) under non-stress conditions. Distilled water treatment had 48.6% more soluble sugars under non-stress, while glutathione and epibrassinolide treatments had 14.5% more under mild stress. Control treatment had the highest malondialdehyde (MDA) amounts under mild and severe stress. Chitosan treatment exhibited a 25% increase in seedling length under severe stress compared to the control. Under non-stress conditions, chitosan treatment had slightly lower seedling length compared to control, while glutathione and epibrassinolide treatments showed the highest lengths. Under mild stress, folic acid, chitosan, and epibrassinolide treatments were superior to control. Under severe stress, distilled water showed a 20% increase, while chitosan treatment showed a 25% increase in seedling length compared to control. Chitosan treatment improved safflower seedling growth under severe osmotic stress through mechanisms including increased osmoprotectant levels, enhanced antioxidant activity, and improved membrane integrity. [ABSTRACT FROM AUTHOR]

The effects of plant-derived smoke on seed germination and plant growth, depending on concentration and time, are widely known. However, there are very few studies demonstrating that it provides tolerance to abiotic stresses. This study comprehensively compares the effects of SW and KAR1 on seed germination and morphological, biochemical, and molecular changes observable in the examined seeds. Moreover, the study shows that it regulates the expression of some genes encoding antioxidant enzymes in apricot seedlings (Prunus armeniaca L.) exposed to salinity stress (100 mM NaCl). The highest germination rate was 1:1000 DS with 60% and 1 μM KAR1 with 72%. In terms of shoot development, root and stem length, 1:100 concentration in the DS group and 1 μM concentration in the KAR1 group gave the best results. The shoot development rates were 95.83% and 87.50% in the DS and KAR1 groups, respectively. While the root length was 137.68 and 141.92 mm in the DS and KAR1 groups, respectively, the stem length was 103.78 and 102.67 mm, respectively. The data revealed that SW (1:1000 v/v) and KAR1 (1μM) increased the expression levels of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPX) genes in the samples taken from the apricot seedlings treated with salt at hours 3, 6 and 9. This increase varies in SW and KAR1 depending on time. When the biochemical results were examined, it was seen that the application of SW and KAR1 to the seedlings under salinity stress led to a significant decrease in the thiobarbituric acid reactive substances (TBARS) content. We can assert that SW is more effective than KAR1 on TBARS content. Morphological, molecular, and biochemical results revealed enhanced germination, growth, gene expression, and TBARS content in apricot seeds and seedlings exposed to SW and KAR1. This data may be applicable to more comprehensive trials. [ABSTRACT FROM AUTHOR]

Pinus sylvestris L. is a widely used tree in landscaping, and therefore, its high-quality planting material is most relevant in Kazakhstan. The recent study evaluated the effects of the various biological preparations on the physiological growth of the P. sylvestris L. seedlings in the ordinary chernozem of Northern Kazakhstan. The study used several methods for evaluation, i.e., sowing and planting, measurements, data compilation, formulation, and analysis, and recommended computer software. In 2022, sowing 20 kg seeds of P. sylvestris ensued on a 0.4 ha area. For the agrochemical assessment of the experimental site, soil samples collected underwent a chemical composition analysis. The morphological parameters of the upper and lower parts of the seedlings also reached identification. Concerning the indicators of agrochemical assessment of the soil after using biological preparations, i.e., Agrarka (1.5%) and Agro-MIX (10%), the sum of macronutrients and exchangeable calcium and magnesium was high. The results also showed that the average number of seedlings incurred enhancements using the Agro-MIX (10%). Therefore, Agrarka and Agro-MIX can be helpful in forest nurseries as effective growth stimulators in growing planting material for tree and shrub species. [ABSTRACT FROM AUTHOR]

Straw returning to the field has an inhibitory effect on seed germination and the early stage of seedling growth. Nanoparticles may contribute to good seed germination and seedling growth under stress. However, the effects of nanoparticles on seed germination and seedling growth of rice under straw returning remain unknown. Two popular aromatic rice varieties, Xiangyaxiangzhan and Meixiangzhan 2, were used as experimental materials. Three doses of iron oxide nanoparticles (Fe2O3 NPs) (i.e., 0 mg L−1, 25 mg L−1, and 50 mg L−1) were used for seed coating, and the nanoparticle-coated seeds were grown at three concentrations of straw extract (i.e., 0 g L−1, 10 g L−1, and 20 g L−1). The seed germination, seedling growth, antioxidant response, and nitrogen metabolism of aromatic rice were studied. The results showed that the aromatic rice varieties responded differently to straw concentration. Straw extract at 10 mg L−1 promoted the germination of Xiangyaxiangzhan but inhibited the germination of Meixiangzhan 2. With increasing straw extract concentration, the antioxidant response of Xiangyaxiangzhan increased. Fe2O3 NPs significantly increased seed germination under straw stress by 5–44%. The growth response of aromatic rice to iron oxide nanoparticle coating treatments varied among the different aromatic rice varieties and straw extract treatments. Therefore, iron oxide nanoparticle coating improved seed germination and regulated early growth and physiological parameters in aromatic rice. [ABSTRACT FROM AUTHOR]

Background: Green gram (Vigna radiata), the third most important pulse crop, is grown in tank-fed, command areas after the harvest of paddy. In such areas, legume trees like Delonix regia and Peltophorum pterocarpum are commonly found and tree parts often fell in watercourses and were flown to crop fields along with irrigation water. Hence, it is necessary to study whether any allelopathic effect is present in these parts of trees which may affect the growth and development of green gram grown in farmland crops. Methods: Collected different tree parts viz., bark, leaf and fresh flower, a matured pod of Delonix regia and Peltophorum pterocarpum, cleaned and soaked distilled water at weight/volume ratio of 1:10 for 24 hrs. Aqueous extracts were filtered and tested for inhibition of green gram. Pot culture experiments were conducted with 10 treatments and four replications. Germination (%), shoot length (cm), root length (cm), fresh weight (mg), dry weight (mg), seedling vigour index-I and vigour index-II in green gram were recorded and the magnitude of inhibition versus simulation in bioassay was compared through response index. Result: Among the plant parts, Delonix regia flower and Peltophorum pterocarpum matured pods suppressed germination (45.00 and 60.00%), shoot length (13.87 and 13.39 cm), root length (4.27 and 10.49 cm), seedling vigour index-I (624.15 and 803.40) and seedling vigour index-II (960.75 and 948.00) respectively in green gram. This might due to presence of inhibitory chemicals in flowers of Delonix regia and matured pods of Peltophorum pterocarpum compared to other plant parts of trees. [ABSTRACT FROM AUTHOR]

Background: Aspergillus niger and A. flavus cause rotting, damping-off, loss in germination and toxification of oil seeds. Aspergillus is a common mold in tropical and Sub-tropical countries and causes aflatoxin contamination. A. flavus and A. niger were responsible for storage rot of groundnut. In addition to storage rot, aflatoxin contamination also leads to adverse effects on consumer health. Therefore, present study was conducted to estimate the impact of both A. niger and A. flavus on seed quality parameters of groundnut. Methods: Effect of major seed borne fungi A. niger and A. flavus on seed quality characters of thirteen different genotypes of groundnut was observed in the present study. All the seedling quality characters were measured as per ISTA guidelines. Result: On an average A. niger caused 25.14, 25.18, 43.99, 26.20 and 44.75 per cent reduction in seed germination, seedling length, seedling vigour index I, seedling dry weight and seedling vigour index II, respectively, over the control whereas A. flavus caused average per cent reduction of 22.38, 24.23, 41.18, 23.92 and 40.95 in seed germination, seedling length, seedling vigour index I, seedling dry weight and seedling vigour index II, respectively, over the control. [ABSTRACT FROM AUTHOR]

Summary: The dimensions and distribution pattern of bordered pits are critical to the xylem water transport function of trees. However, studies on the three-dimensional distribution pattern of pits across xylem growth rings are still limited. Here, Micro-Computed Tomography (Micro-CT) was used to acquire xylem images of two-year-old Platycladus orientalis seedlings. We analyzed the tracheid lumen diameter of 665 tracheids, pit volume, and pit diameter of 11 810 inter-tracheid pits from three radial profiles. The volume ratio of inter-tracheid pits was about 0.90–0.96%. The average pit diameter was 6.8 μm and the average pit volume was 58.9 μm3, and more than 80% of the pits had a diameter of 5–8 μm and a volume of 20–90 μm3. Both the pit diameter and the pit volume increased gradually in the radial direction from the second-year growth ring to the current-year growth ring, and the pit diameter and volume were significantly higher in earlywood than in latewood. The distribution pattern of the tracheid diameter was similar to that of the pit diameter, and the wider the tracheids, the larger the pits. The distribution of bordered pits in P. orientalis may be a critical trait explaining the xylem embolism spread pattern in this species. [ABSTRACT FROM AUTHOR]

The giant sequoia, a serotinous conifer naturally occurring in mixed‐conifer forests of the southern and central Sierra Nevada, California, USA, is the world's largest tree species. Giant sequoia reproduction has been severely lacking over the past century, due to fire exclusion, creating a significant conservation threat. Previous research on postfire sequoia reproduction in high‐severity fire areas, relative to low‐ and moderate‐severity areas, is limited. At 6 years postfire, we investigated giant sequoia reproduction in a high‐severity fire area, and nearby low‐/mixed‐severity fire areas, in the Nelder Grove, which burned in 2017 in the Railroad fire. Postfire giant sequoia reproduction was positively correlated with fire severity in terms of density, height (growth), and proportion (relative to other conifer species), and sequoia seedling/sapling density was positively correlated with percent shrub cover. There was no correlation between distance to live sequoia seed source and density of sequoia reproduction. More research is needed in other mixed‐severity fire areas, with larger high‐severity fire patches, to determine whether a similar postfire response occurs elsewhere. [ABSTRACT FROM AUTHOR]

Epiphytic orchids comprise 68% of vascular epiphytes globally; nevertheless, many are endangered. One such epiphytic orchid is Phalaenopsis japonica, which is widely used in the floricultural industry. This study aimed to identify the mycorrhizal fungi of adult P. japonica and their roles in seed germination and seedling development. Root samples were collected from 32 adults across 4 sites in southern Japan, and mycorrhizal fungi were identified using Sanger and high-throughput sequencing (HTS). The results show phylogenetically diverse mycobionts, mainly Ceratobasidiaceae (CE) and Tulasnellaceae (TU), with dominant OTUs designated CE6 and CE22. Sanger sequencing found 9 OTUs, 4 CE, and 5 TU; HTS detected 22 OTUs, 4 CE, 16 TU, and 2 Serendipitaceae. Seeds inoculated with CE6 improved germination and protocorm development compared with other strains. In addition, asymbiotic seedlings inoculated with CE6, CE22, and TU18 displayed varying effects in growth, with CE6 being the most notable. While TU18 did not promote seed germination, it effectively promoted leaf development in seedlings. Overall, Ceratobasidiaceae was predominantly associated with seed germination, seedling growth, and the adult stages, with CE6 and CE22 becoming the primary partners throughout the life history of P. japonica. Our findings illuminate mycorrhizal symbiosis in epiphytic habitats, offering conservation and commercial production insights. [ABSTRACT FROM AUTHOR]

Drought stress poses significant productivity challenges to wheat. Several studies suggest that lower malondialdehyde (MDA) content may be a promising trait to identify drought-tolerant wheat genotypes. However, the optimal polyethylene glycol (PEG-6000) concentration for screening seedlings for drought tolerance based on MDA quantification is not clear. The aim of this study was to verify whether a 10% (w/v) PEG-6000 concentration-induced water stress was reliable for discriminating between twenty-two drought-susceptible and drought-tolerant tetraploid wheat (Triticum turgidum spp. durum, turanicum, and carthlicum) accessions based on MDA quantification. To do so, its correlation with morpho-physiological traits, notoriously related to seedling drought tolerance, i.e., Seedling Vigour Index and Seedling Water Content, was evaluated. Results showed that MDA content was not a reliable biomarker for drought tolerance, as it did not correlate significantly with the aforementioned morpho-physiological traits, which showed, on the contrary, high positive correlation with each other. Combining our study with the cited literature, it clearly emerges that different wheat genotypes have different "water stress thresholds", highlighting that using a 10% PEG-6000 concentration for screening wheat seedlings for drought tolerance based on MDA quantification is not reliable. Given the conflicting results in the literature, this study provides important insights for selecting appropriate methods for evaluating wheat seedling drought tolerance. [ABSTRACT FROM AUTHOR]

Due to intense ash dieback, this research tested the bioactivity of Thymus vulgaris, Lavandula angustifolia, and Cupressus sempervirens essential oils (EO) against Hymenoscyphus fraxineus. In vitro testing showed that EOs had a pronounced fungitoxic effect on H. fraxineus. The most effective EO was extracted from T. vulgaris, while EOs obtained from L. angustifolia and C. sempervirens were less effective and showed the same effect. At a concentration of 1%, all tested EOs inhibited mycelial growth, while 0.01% and 0.1% concentrations of EO extracted from T. vulgaris also inhibited the growth of H. fraxineus. The in planta test of EO extracted from T. vulgaris conducted on three‐year‐old Fraxinus angustifolia seedlings showed a reduction in the size of necrotic lesions and a better crown condition compared to untreated seedlings. This research demonstrates, for the first time, the efficiency of EOs in suppressing ash dieback making a path for the development of new biological protection measures against H. fraxineus. [ABSTRACT FROM AUTHOR]

Intercropping soybean in tea plantations is a sustainable cultivation system that can improve the growing environment of tea plants compared to monoculture tea. However, the effects of this system on the photosynthesis activity of tea seedlings have yet to be reported. Therefore, we used tea cultivar 'Zhongcha108' as experimental materials to investigate the effects of intercropping soybean on the canopy spectral parameters and photosynthesis activity of tea seedlings. Canopy spectral reflectance data showed that soybean–tea intercropping (STS) improved the reflectance of 720, 750 and 840 nm bands in tea seedlings' canopy. The vegetation indexes (VIs) value related to photosynthetic pigments in STS was obviously higher than monoculture tea (T). In addition, the Fv/Fm and SPAD value in STS were also clearly higher. Transcriptome analysis data indicated that STS induced the expression of light-harvesting complex (LHC) genes, photosystem subunit (Psbs and Psas) genes and dark reaction biological process genes (FBP1, RPE, Calvin cycle protein CP12-1 and transketolase). These results indicate that STS enhanced the photosynthesis activity. The metabolome analysis showed that STS promoted the accumulation of carbohydrate metabolites, which further provided evidence for the enhancement of photosynthesis in the leaves of tea seedlings. This study enhanced our understanding of how intercropping soybeans in a young tea plantation improves the photosynthesis activity to promote tea seedlings' growth and development. [ABSTRACT FROM AUTHOR]

Salt stress exerts adverse effects on yield by inhibiting or delaying seed germination and impeding seedling growth. Additionally, different salt concentrations have adverse effects on plant wet and dry weight and stem and shoot development. Crotalaria juncea L., the fastest-growing species within the Crotalaria genus, demonstrates a high degree of adaptability to both tropical and subtropical climates. To assess the tolerance of sunn hemp to salinity during the germination and early seedling stages, several indicators were determined at different (0, 50, 100, 150, 200, 250, and 300 mM) salt concentrations. Germination was conspicuously absent at salt concentrations of 250 mM and 300 mM. Notably, seedling characteristics, such as shoot length, root length, root fresh weight, seedling fresh weight, retention capability of the shoot, and the relative water content, experienced adverse effects with escalating salt concentrations. Intriguingly, the apex of seedling and root dry weights manifested at the pinnacle of salt concentration at 200 mM. Despite the discernible influence of heightened salt concentrations during the nascent seedling stage, the tolerance index was quantified at 100 mM, 150 mM, and 200 mM. Analyzing the study results through the lens of macro-minerals revealed an augmentation in Na and Cl content concomitant with increasing salt concentrations. [ABSTRACT FROM AUTHOR]

To address the lack of effective monitoring, evaluation, and prediction methods for water stress in citrus seedlings, we conducted 10 sets of water stress gradient experiments. Based on the experimental dataset, we constructed, trained, and improved an MLP classification model for citrus seedling water stress. In addition, we developed a monitoring, evaluation, and prediction system based on this model. The experiments demonstrated that 7 days of slight water stress can induce changes in overall root wilting and growth stagnation, and the chlorophyll content in the leaves can decrease by up to 11.78%. Furthermore, the optimal VWC for seedlings was [45%, 50%], the boundary of drought was [20%, 25%], and the boundary of waterlogging was [50%, 55%]. We validated the effectiveness of the system in assessing the growth status of seedlings over the past 7 days and predicting it after 7 days through testing sets and experiments on slight water stress. We found that the system achieved non-destructive remote monitoring, evaluation, and prediction of slight water stress in citrus seedlings, thus enhancing seedling quality. These research findings provide valuable insights into water stress management in citrus seedlings and other crops. [ABSTRACT FROM AUTHOR]

Plant growth and physiology can be affected by environmental and chemical factors that have the potential to influence yields. Among the factors that influence plant growth, neonicotinoid seed treatments have shown significant effects on plant growth, particularly in cotton. The dual benefits seen from neonicotinoids on plant growth and insect control show promise in improving cotton yields but little is known about how different seed treatments affect seedling physiology. A greenhouse experiment was undertaken to investigate how three neonicotinoid seed treatments (clothianidin, thiamethoxam, and imidacloprid) affect the physiology and growth of cotton seedlings in controlled environmental conditions. A randomized complete block design was used to examine seed treatments and an untreated control. Cotton seeds were treated, grown, and evaluated for physiological changes until the fifth true leaf-stage and measurements were taken at each of these stages. Data were collected on plant height, shoot fresh weight, leaf area, root length, and root biomass. In addition, chlorophyll pigments and nutrient analysis were performed on cotton seedlings. The seedlings of imidacloprid treated seeds had greater height, shoot fresh mass, leaf area, and relative growth rate by the fifth true leaf stage compared to other treated plants; however, clothianidin showed comparative performance at earlier stages in plant development that equilibrated over time. While all neonicotinoid seed treatments showed positive effects, imidacloprid showed the most potential as a bioactivator on plant growth. [ABSTRACT FROM AUTHOR]

The tolerance of Moringa oleifera plants to excess K may be linked to nutritional mechanisms, but studies are lacking. The present study was conducted to analyze the tolerance of Moringa oleifera to nutritional imbalance and its importance in the growth of plants submitted to high doses of K in the absence and presence of N. The experiment was conducted in pots with 9 dm3 of Oxisol in a 4 × 2 factorial scheme, with potassium doses of 0, 110, 190, and 265 mg dm−3 combined with nitrogen doses of 0 and 100 mg dm−3. The increase in K uptake by moringa is enhanced by N supply but decreases the uptake of Ca and Mg. Notwithstanding, this was of little importance as the soil cultivated had adequate Ca and Mg contents and was sufficient for adequate plant nutrition without impairing plant growth. The moringa plant is tolerant to nutritional imbalances when grown in environments with high K content probably because N favors an increase in Mg use efficiency, avoiding biological disturbances. The results of this study contributed to our understanding of how moringa induces nutritional mechanisms of action to deal with excess K in crops. [ABSTRACT FROM AUTHOR]

The plant growth regulator gibberellic acid (GA) and the herbicide glyphosate were examined for their possible interactions with growth and phenolic metabolism in soybean [Glycine max (L.) Merr. Cv. Hill] seedlings. GA caused increases in phenylalanine ammonia-lyase activity (PAL) (per axis basis) above those of the control seedling levels 48 h after treatment in light-grown seedlings. This effect increased to two-fold greater than control levels by 72 and 96 h after treatment. In dark-grown plants, GA had no effect on PAL levels at 24 h, reduced levels at 48 and 72 h, and increased PAL at 96 h. Early studies in our lab reported that glyphosate increased PAL levels, and also reduced hydroxyphenolic compound accumulation in both light- and dark-grown soybean seedlings. Treatments of GA plus glyphosate caused additive increases in PAL activity in light-grown seedlings, but GA lowered glyphosate's increase in PAL levels at 48–96 h after treatment in dark-grown seedlings. GA had little effect on hydroxyphenolic compound levels in either light- or dark-grown seedlings. GA treatment alone did not significantly affect root elongation, but stimulated hypocotyl and epicotyl elongation and caused marginal reversal of glyphosate inhibition of elongation in roots, hypocotyls, and epicotyls in light-grown plants. These results show some differential effects of GA and glyphosate on growth and phenolic metabolism, and their interactions that are dependent on plants grown in light or darkness. [ABSTRACT FROM AUTHOR]

Zelkova schneideriana Hand.-Mazz is a valuable ornamental tree and timber source, whose seedling breeding and large-scale cultivation are restricted by low seed germination and seedling rates. The regulatory mechanisms underlying seed germination and seedling establishment in Z. schneideriana remain unknown. This study conducted metabolomic and transcriptomic analyses of seed germination and seedling establishment in Z. schneideriana. Regular expression of genes and metabolite levels has been observed in plant hormone signal transduction, starch and sucrose metabolism, linoleic acid metabolism, and phenylpropanoid biosynthesis. The reduction in abscisic acid during seed germination may lead to seed release from dormancy. After the seed is released from dormancy, the metabolic levels of auxin, cytokinins, brassinolide, and various sugars are elevated, and they are consumed in large quantities during the seedling establishment stage. Linoleic acid metabolism is gradually activated during seedling establishment. Transcriptome analysis showed that a large number of genes in different metabolic pathways are upregulated during plant establishment, and material metabolism may be accelerated during seedling establishment. Genes regulating carbohydrate metabolism are altered during seed germination and seedling establishment, which may have altered the efficiency of carbohydrate utilization. In addition, the syntheses of lignin monomers and cellulose have different characteristics at different stages. These results provide new insights into the complex mechanisms underlying seed germination and seedling establishment in Z. schneideriana and other woody plants. [ABSTRACT FROM AUTHOR]