Shoot Weight Research Articles

Photosynthetic efficiency and water retention in okra (Abelmoschus esculentus) contribute to tolerance to single and combined effects of drought and heat stress.

The co-occurrence of drought and heat significantly hampers plant productivity. Although their impacts are well studied, these studies have been based on the effects of individual stressors rather than their combined influence. Okra is crucial for food and nutritional security and livelihoods in many regions, yet it remains under-researched and unimproved. Okra has been proven to be sensitive to both drought and heat stress. This study employed a cost-effective phenotyping method to assess key traits characterising the diversity of okra morphophysiological responses to independent and interactive heat-drought stresses. This study aimed to understand okra responses to stress, identify stress-resilient traits, and characterise okra genotypes. We also addressed the need to examine interactive stress effects, which mirror real-world scenarios more accurately than single-stress studies. Sixty-three okra genotypes were subjected to heat, drought, or concurrent heat-drought stress at the seedling stage in improvised climate-controlled chambers. The germplasm exhibited significant variations in response to the various stresses. The broad-sense heritability was high (> 0.60) for traits such as chlorophyll content, plant biomass, performance indices, electrolyte leakage, and total leaf area. Drought stress alone had a more pronounced effect than heat stress alone, and the adverse impact was worsened under combined heat and drought stress. The interactive impact of drought and heat was more likely additive than antagonistic or synergistic. A positive and strong relationship was observed between photosynthetic efficiency parameters such as the Fv/Fm ratio, chlorophyll content, relative water index, and biomass parameters such as dry shoot weight. The 63 okra genotypes were classified into three distinct clusters, suggesting potential for future breeding efforts. Okra genotype considered to be tolerant or climate resilient (such as GH170, V1060831, GH174, V1060874, and GH106) to drought and heat, maintained enhanced photosynthetic efficiency and high internal water potential, possibly reducing osmotic and oxidative damage. This study revealed some mechanisms underlying the adaptation of okra genotypes to independent and combined heat and drought stress. The results provide a basis for breeding efforts to develop climate-resilient okra varieties.

Induced Phytomanagement of Multi-Metal Polluted Soil with Conocarpus erectus Supported by Biochar, Lignin, and Citric Acid

Induced heavy metals (HMs) phytoextraction from heavily contaminated soils is challenging, as high HM bioavailability causes phytotoxicity and leaching. This study introduces a novel approach for HM immobilization with biochar (BC) and lignin (LN), and later their controlled mobilization with citric acid (CA) in soil. Conocarpus erectus was grown for 120 days in shooting-range soil (SS) polluted with Pb, Cr, Cd, Ni, and Cu. HM concentrations in parts of the plants, their percentage removal, and leaching from SS were measured. Moreover, plant biochemical parameters such as the contents of chlorophyll a (Chl-a), chlorophyll b (Chl-b), protein, ascorbic acid (AsA), amino acids, and total phenolics, along with biophysical parameters such as relative water content (RWC) and water uptake capacity (WUC), were also inspected. Adding BC, LN, and BC+LN to SS improved biomass, as well as the biophysical and biochemical parameters of plants, while efficiently reducing HM concentrations in plant parts, DTPA extract, and leachates compared to the control (CK). However, the greatest amplifications in plant height (82%), dry weight of root (RDW) (109%), and dry weight of shoot (SDW) (87%), plant health, and soil enzymes were noted with the BC+LN+CA treatment, compared with the CK. Moreover, this treatment resulted in Pb, Cr, Cd, Ni, and Cu removal by 68, 30, 69, 59, and 76% from the SS compared to the CK. Surprisingly, each HM concentration in the leachates with BC+LN+CA was below the critical limits for safer water reuse and agricultural purposes. Initial HM immobilization in HM-polluted soils, followed by their secured mobilization during enhanced phytoextraction, can enhance HM removal and reduce their leaching without compromising plant and soil health.

Effect of Media Formulation on Survival and Growth Performance of Star Jasmine (Jasminum multiflorum Burm. f. Andrews) Propagation by Stem Cuttings

Present study investigated “Effect of media formulation on survival and growth performance of star jasmine (Jasminum multiflorum Burm. f. Andrews) propagation by stem cuttings”. during 2023-2024 using a Randomized Block Design (RBD) with eight treatments and three replications with eight treatments i.e., T5: soil + vermicompost + cocopeat (1:1:1). The treatments comprised various combinations of soil, farmyard manure (FYM), cocopeat, sand, rice husk, and vermicompost. The results indicated that the propagation media significantly affected the growth parameters. Notably, Treatment T5 i.e. soil + vermicompost + cocopeat (1:1:1) demonstrated superior performance, with the shortest sprouting time (9.67 days), highest survival rate (78.67%) and overall enhanced growth attributes, including sprout number, sprout length, plant height, leaf area, and root and shoot weights. The findings suggest that soil + vermicompost + cocopeat (1:1:1) is an optimal medium for propagating of star Jasmine, warranting further studies to confirm its efficacy across different locations and seasons.

Characterization of the species of Pythium associated with corn seedlings in Delaware.

Corn (Zea mays L.) is the top grain crop by hectares grown in Delaware (DE). Increased pre- and post-emergence damping-off in corn caused by Pythium species have been observed in recent seasons. To date, no characterization studies have been performed to understand Pythium species diversity in DE. Symptomatic corn seedlings were collected from 33 fields across DE in 2019 and 2020. Isolates were obtained from infected root tissues and identified by molecular sequencing. In total, 14 species were recovered: P. aristosporum, P. arrhenomanes, P. attrantheridium, P. catenulatum, P. dissotocum, P. graminicola, P. inflatum, P. irregulare, P. oligandrum, P. periplocum, P.spinosum, P. sylvaticum, P. tardicrescens, and P. torulosum. The dominant species recovered was P. graminicola, accounting for 66% of the isolates. Five species were screened for fungicide sensitivity to calculate the EC50 of mefenoxam, ethaboxam, and picarbutrazox which are the most commonly used active ingredients to manage species of Pythium in corn seed treatment packages. All species tested were sensitive to mefenoxam and picarbutrazox. For ethaboxam, P. torulosum was the only species with an EC50 value > 10 µg ml 1. Ten species were screened for fungicide sensitivity to mefenoxam, ethaboxam, or picarbutrazox at 18, 21, and 25ºC. As temperatures increased, percent inhibition was reduced in 40, 70, and 80% of the species screened for sensitivity to ethaboxam, picarbutrazox, and mefenoxam, respectively. Nine of these species were screened for isolate aggressiveness in greenhouse panels to examine impact on emergence, shoot height, shoot weight, and root weight. While all species were recovered from inoculated roots, P. arrhenomanes, P. attrantheridium, P. spinosum, and P. sylvaticum had the greatest root weight reduction.

Effect of Different Zn Concentrations on Crop Growth and Root Nodulation in Yard-Long Bean (Vigna unguiculata L.)

An experiment was conducted to study the effect of Zinc (Zn) as a micronutrient on growth and nodulation in Vigna unguiculata L. The experiment was carried out as a pot experiment in the Crop Farm, Faculty of Agriculture, Palachcholai, Eastern University, Sri Lanka from August to November 2023. The experiment was laid out in Complete Randomized Design with six treatments and four replicates. The treatments are T1 (Control), T2 (50 mg ZnSO4/kg soil), T3 (100 mg ZnSO4/kg soil), T4 (150 mg ZnSO4/kg soil), T5 (200 mg ZnSO4/kg soil) & T6 (250 mg ZnSO4/kg soil). The experiment used source of Zinc in the form of Zinc Sulphate (ZnSO4,5H2O) which yard-long bean plants can grow. The experiment results showed that, T2 treatment, the soil treated with 50 mg ZnSO4/kg soil significantly increase the Plant height, Chlorophyll content, Leaf area, Fresh weight of shoot & root, Dry weight of shoot & root, Number of nodules, Effective nodule percentage, as well as Soil respiration compared to the other treatments. However, beyond the level of 200 mg ZnSO4/kg soil, reduces the growth & nodulation of Vigna unguiculata L. and this shows that the level 200 mg ZnSO4/kg soil and beyond that level were the toxic level to the Vigna unguiculata L. Accordingly, the treatment T2 (50 mg ZnSO4/kg soil) was at the micronutrient level of Zn concentration which involved in many key cellular functions and show the best positive effect on growth and nodulation in Vigna unguiculata L. The results clearly indicate that, Zn can be use as a micronutrient up to a trace level in inducing plant growth and nodulation. However, at higher levels of Zn may act as heavy metal and cause phyto-toxicity in plants.

Photoperiodic Effect on Growth, Photosynthesis, Mineral Elements, and Metabolome of Tomato Seedlings in a Plant Factory

The duration of light exposure is a crucial environmental factor that regulates various physiological processes in plants, with optimal timing differing between species and varieties. To assess the effect of photoperiods on the growth and metabolites of a specific truss tomato cultivar, three photoperiods (12 h, 16 h, and 20 h) were tested in a plant factory. Growth parameters, including plant height, stem diameter, fresh and dry weights of shoots and roots, photosynthetic characteristics, mineral content, and metabolome profiles, were analyzed under these conditions. The results indicated that prolonged light exposure enhanced plant growth, with the highest photosynthesis and chlorophyll content observed under a 20 h photoperiod. However, no significant correlation was observed between the photoperiod and the mineral element content, particularly for macro minerals. Metabolome analysis revealed that different photoperiods influenced the accumulation of metabolites, particularly in the lipid metabolism, amino acid metabolism, and membrane transport pathways. Long periods of light would enhance photosynthesis and metabolism, improving the rapid growth of tomato seedlings. Overall, this study provides a theoretical basis for understanding the responses of truss tomato cultivars to varying photoperiods in plant factories and proposes an optimizable method for accelerating the progress of tomato seedling cultivation.

Comparative Analysis of Two Soybean Cultivars Revealed Tolerance Mechanisms Underlying Soybean Adaptation to Flooding

Flooding stress poses a significant challenge to soybean cultivation, impacting plant growth, development, and ultimately yield. In this study, we investigated the responses of two distinct soybean cultivars: flooding-tolerant Nanxiadou 38 (ND38) and flooding-sensitive Nanxiadou 45 (ND45). To achieve this, healthy seedlings were cultivated with the water surface consistently maintained at 5 cm above the soil surface. Our objective was to elucidate the physiological and molecular adaptations of the two cultivars. Under flooding stress, seedlings of both cultivars exhibited significant dwarfing and a notable decrease in root length. While there were no significant differences in the dry weight of aboveground shoots, the dry weight of underground shoots in ND38 was strikingly decreased following flooding. Additionally, total chlorophyll content decreased significantly following flooding stress, indicating impaired photosynthetic performance of the cultivars. Moreover, malondialdehyde (MDA) levels increased significantly after flooding, particularly in the ND45 cultivar, suggesting heightened oxidative stress. Expression analysis of methylation and demethylation genes indicated that MET1 and DME play crucial roles in response to flooding stress in soybeans. Meanwhile, analysis of the hemoglobin family (GLBs), aquaporin family (AQPs), glycolytic pathway-related genes, and NAC transcription factor-related genes identified GLB1-1 and GLB1-2, GLB2-2, PIP2-6, PIP2-7, TIP2-2, TIP4-1, TIP5-1, Gm02G222400 (fructose-bisphosphate aldolase), Gm19G017200 (glucose-6-phosphate isomerase), and Gm04G213900 (alcohol dehydrogenase 1) as key contributors to flooding tolerance in both soybean cultivars. These findings provide crucial insights into the physiological and molecular mechanisms underlying flooding tolerance in soybeans, which could guide future molecular breeding strategies for the development of flooding-tolerant soybean cultivars.

The simultaneous application of fulvic acid and protein hydrolysate biostimulants enhances cucumber responses to Fe deficiency

Iron (Fe) is widely recognized as a critical factor in limiting crop production; however, eco-friendly strategies to address its deficiency are still required. The use of biostimulants has displayed promising results in mitigating Fe deficiency. Our hypothesis was that the combined application of two biostimulants with distinct molecular structures - fulvic acid (FA) and protein hydrolysate (PH) - could be more effective than the use of a single compound. The simultaneous presence of FA and PH (MIX) in a Fe-free nutrient solution led to a redistribution of endogenous Fe, resulting in a higher leaf SPAD index. Furthermore, the addition of FeCl3 as a Fe source (resupply) in MIX-treated plants enhanced the biostimulant effect, as evidenced by increased dry root and shoot weight and a more developed root system. In addition, the expression of Strategy-I-related genes, CsFRO1 and CsIRT1, remained elevated. These effects can be attributed to improved interaction between the roots and biostimulants through the formation of the FA-PH complex, as demonstrated by circular dichroism and isothermal titration calorimetry analyses.

Morpho-physiological traits and stress indices reveal divergence in early-stage salt stress response in elite soybean germplasm

This study assessed the salt stress response of seventy soybean genotypes by exposing seedlings to sodium chloride (NaCl) concentrations of 0, 75, 100, and 125 mM. Salinity stress significantly reduced root length, shoot length, fresh and dry root/shoot weight, and root/shoot ratio. A total of 62 genotypes germinated at 125 mM, showing significant phenotypic variation in traits such as root length, shoot length, fresh shoot weight, and dry shoot weight. Pearson’s correlation analysis revealed a strong positive correlation between most morpho-physiological traits, suggesting their interdependence. Eight salinity tolerance indices i.e., Fresh Weight Stress Tolerance Index (FWSI), Dry Weight Stress Tolerance Index (DWSI), Root Length Salinity Index (RLSI), Shoot Length Salinity Index (SLSI), Salinity Tolerance Index (STI), Salinity Susceptibility Index (SSI), Tolerance Index (TI), and Percent Reduction (PR) were calculated to assess genotypes response. Na+ concentration and antioxidant activities significantly increased under salt stress compared to the control. The activities of antioxidant enzymes, as well as the levels of reactive oxygen species (ROS) such as H2O2 and O2−, were markedly higher under salt stress compared to the control. Hierarchical cluster analysis grouped genotypes into six clusters, with clusters V and VI comprising genotypes exhibiting higher salt tolerance based on high FWSI, DWSI, and STI values, and low PR, SSI, and TI values. Eight salinity tolerance indices, including Fresh Weight Stress Tolerance Index (FWSI), Dry Weight Stress Tolerance Index (DWSI), Root Length Salinity Index (RLSI), and Salinity Tolerance Index (STI), were used to evaluate the genotypes’ responses. The study revealed that the average FWSI value for all genotypes under treatments was 54.20 ± 12.93. The highest FWSI was recorded for the genotype Black (92.52), followed by NIBGE-224 (84.70) and NIBGE-183 (81.05). In contrast, Malakand-96 had the lowest FWSI (28.49), followed by SPS-10 (32.74) and SPS-08 (34.55). PGRA-91 had the highest STI (0.83), followed by SPS-9 (0.75) and NIBGE-115 (0.72), while NIBGE-335, SPS-24, and Malakand-96 had the lowest STI values. Positive correlations were observed between root length and shoot length (0.69**), shoot length and fresh shoot weight (0.63**), and other related traits. Overall, this study identified promising soybean genotypes with varying degrees of salt tolerance. These findings can be utilized in breeding programs to develop salt-tolerant soybean varieties for salinity-affected agricultural lands.

Plant growth promoting Rhizobacteria for sustainable tomato production

Numerous phosphate solubilizing bacteria (PSB) are found in the rhizosphere, benefiting the host plant in different mechanisms and promoting sustainable agriculture. They improve soil fertility with minimum cost requirements using an eco-friendly approach, which is an essential attribute for small-scale farm production. Thus, isolation, characterization, and evaluation of symbiotic effectiveness are hierarchical procedures to develop bioinoculants. Using a dual (plate and liquid medium) screening technique and a greenhouse trial, four potential PSB strains (Mk-1–25, Mk-13–16, Mk-20–7, and Mk-20–20) were selected from tomato rhizosphere soil. All isolates exhibited the following traits: produced colony clear-zone, lowered liquid medium pH, gram-positive, produced urease and IAA, dissolved substantial P from various substrates, symbiotically effective, and improved tomato growth and yield. Taxonomically, they belong to Bacillus and Priestia species (i.e., Mk-1–25 Bacillus halotolerance, Mk-13–16 Bacillus amyloliquefaciens, Mk-20–7 Bacillus megaterium, and Mk-20–20 Priestia megaterium). Among the current strains, Bacillus halotolerance recorded higher SI (3.11), was able to grow in extreme conditions (10% salt, up to 45 °C), produced HCN and siderophore, and improved tomatoes’ shoot length and weight, in contrast, Mk-20–20 produced HCN, siderophore, was able to fix nitrogen, improved tomato germination, shoot dry weight, and fruit weight. Various P-supplements (Ca3(PO4)2, bonemeal, FePO4, AlPO4, compost, and DAP fertilizer) were added to induce tomato-strain symbiotic interaction; hence, compost substantially promoted the interaction and resulted in higher symbiotic effectiveness. Ca3(PO4)2 was a good media composite preferred by most PSB strains; consequently, a higher concentration (219 µg/ml) of dissolved P was recorded from the liquid medium after 10 days of incubation than other substrates. Based on the data obtained from laboratory and greenhouse trials, the current strains were found to be potential candidate. Future work should confirm their efficacy at the field level using model host crops at different sites to recommend them as farm inputs and biofertilizer.

Морфофизиологический тестинг Linum ussitatissimum L. в условиях различного уровня хлоридного засоления

The selection of resistant varieties under conditions of abiotic stress is an urgent direction in the adaptive selection of flax. The presented work reflects the assessment of the phenotypic variability of 12 hybrid combinations of flax-longshanks according to the morphophysiological parameters of seedlings under the action of chloride salinization of two levels (E1, E2). The genotypes of flax of the fourth (F4) – fifth (F5) generations were used as objects of research. Significant differences (p>0.05, p>0.01, p>0.001) between hybrid populations and media were revealed for most of the studied indicators. Genotypic features (G) caused the formation of flax combinations of dry shoot mass, chlorophyll content in cotyledon leaves (16.2 -37.7%), medium – raw shoot mass and chlorophyll content (30.6 – 50.0%), interaction of genotype and medium – root length, germination index (26.8 – 45.5%). The negative effect of two environmental conditions on seed germination and further development of flax seedlings has been established. By root length Gen1, Gen5, Gen9, Gen10, Gen11; shoot length – Gen1, Gen2, Gen3, Gen7, Gen12; raw root weight – Gen1, Gen4, Gen5, Gen10; dry root weight – Gen1, Gen4, Gen5; the crude mass of the shoot is Gen1, Gen5; the dry mass of the shoot is Gen1, Gen4, Gen5, Gen7; the chlorophyll content is Gen2, Gen8. Resistance to salt stress in two environmental conditions was characterized by 41.6% of combinations in shoot length, 33.3% in raw root weight, dry shoot weight, 25.0% in dry root weight, 16.6% in raw shoot weight, chlorophyll content, which can be recommended for further breeding work when developing an adaptive strategy for creating new flax varieties -dolgunts in the soil and climatic conditions of the Tyumen region. Keywords: FLAX, HYBRIDIZATION, STABILITY INDEX, SPAD-502 PLUS, SELECTION

Bacterial endophyte Pseudomonas mosselii PR5 improves growth, nutrient accumulation, and yield of rice (Oryza sativa L.) through various application methods

BackgroundPseudomonas spp. have drawn considerable attention due to their rhizospheric abundance and exceptional plant growth-promoting attributes. However, more research is needed on the optimal application methods of Pseudomonas mosselii for rice growth, nutrient accumulation, and yield improvement. This research explored the application of the endophytic bacterium P. mosselii PR5 on rice cultivar BRRI dhan29 with four treatments: control, seedling priming, root drenching, and bacterial cell-free culture (CFC) foliar application.ResultsPR5 led to better rice growth, improved nutrient acquisition, and higher yields compared to the control, regardless of the application method used. The highest results in fresh weight of root (146.93 g/pot), shoot (758.98 g/pot), and flag leaf (7.88 g/pot), dry weight of root (42.16 g/pot), shoot (97.32 g/pot), and flag leaf (2.69 g/pot), and grains/panicle (224.67), were obtained from seedling priming treatment, whereas root drenching resulted in maximum plant height (105.67 cm), root length (49.0 cm), tillers/pot (23.7), and panicles/pot (17.67). In all three application methods, rice grain yield per pot was higher in PR5 inoculated treatments, compared to the control. The amount of P, Mg and Zn in the shoot and N, P, Ca, Mg and Si content in the flag leaf was significantly increased along with effective suppression of naturally occurring blast disease in bacterial CFC foliar application, validated by multivariate analysis.ConclusionOur results indicated that rice seedlings priming with PR5 improved rice growth, yield and nutrient uptake, whereas CFC foliar application significantly increased the concentration of most nutrients in the rice plant and suppressed the naturally occurring rice blast disease. This research highlights the significant potential of P. mosselii PR5 in enhancing rice growth, yield, and nutrient uptake, particularly through seedling priming and CFC foliar application methods.

Refinement of the in vitro propagation process of Petunia (Petunia hybrida) plant

Petunia (Petunia hybrida) is currently one of the most favored ornamental potted flowers. Tissue culture-based propagation has proven to be effective in terms of multiplication rates and consistent seedling quality, meeting the demand for Purple Petunia varieties. In this study, Sodium hypochlorite (NaOCl) with various culture media [Murashige and Skoog (MS), ½ MS, and Knudson C] and growth regulators [6-benzyladenine (BA), Indole 3-butyric acid (IBA), and Naphthaleneacetic acid (NAA)] were utilized to determine the appropriate concentrations and durations for sample sterilization, shoot multiplication, and root induction processes of Purple Petunia. Evaluation criteria for in vitro Purple Petunia included parameters, such as survival rate, contamination rate, dead samples, number of shoots, shoot height, number of roots, and root length. The results indicated that stem sample sterilization at a 5% NaOCl concentration for 10 min yielded the highest survival rate (70.7%) at 14 days post-culture initiation. Purple Petunia stem samples, when cultured in MS medium supplemented with 0.5 mg/L BA combined with 0.1 mg/L IBA, demonstrated the most efficient shoot multiplication with a multiplication rate of 26.9, a shoot weight of 3.6 g, a leaf/shoot ratio of 4.6, and a shoot height of 3.0 cm. The MS medium supplemented with 0.1 mg/L NAA was found to be optimal for root induction, resulting in the highest number of roots at 32.1 roots/plant and a root length of 7.0 cm. Briefly, this research provided fundamental insights into the in vitro propagation process of disease-free Purple Petunia multiplication.

SYNERGISTIC EFFECT OF BACILLUS MUCILAGINOSUS AND PSEUDOMONAS FLUORESCENS ON THE AVAILABILITY OF SOIL POTASSIUM, GROWTH AND YIELD OF CUCURBITA PEPO L.

A field experiment was carried out at the field of Agricultural Research and Experiments Station during the season 2021-2022 in order to study the synergestic effect and compatible between Bacillus mucilaginosus and Pseudomonas fluorescens when they added as combination on potassium availability in the soil and on some plant growth characteristics and yield of Cucurbita pepo L. The experiment included four treatments B0, control , B1 addition of Bacillus mucilaginosus inoculum, B2 addition Pseudomonas fluorescens inoculum and B1 B2 addition of acombination of B1 and B2 inoculum . The experiment was conducted by using randomised complete blocks design in three replicates . The results showed that the co- inoculation with Bacillus mucilaginous and Pseudomonas fluorescens significant effect on quantity of soluble,exchangeable potassium as well as the plant height, dry weight of shoots, percentage of potassium in the shoot and in the fruits and total yield as compared with individual inoculation for any bacteria B1 or B2 which refers to positive synergestic effect. B1B2 treatment achieved the highest mean of soluble, exchangeable potassium which amounted to(0.163,0.856) cmol kg-1 soil respectively with an increase of (21.642 %, 15.676%) and (33.606%, 22.636%) of what was achieved by treatment (B1, B2) for the mean of soluble, exchangeable potassium respectively . B1B2 treatment achieved the lowest mean of( non-exchangeable and mineral) potassium which amounted to (35.280) cmol kg-1 soil.

Key Soil Abiotic Factors Driving Soil Sickness in Lycium barbarum L. Under Long-Term Monocropping

Sustainable cultivation of Lycium barbarum L. (L. barbarum) in northwest China faces challenges due to soil sickness. While previous studies have explored variations in L. barbarum’s root-associated microbiota, the impact of soil properties on its growth performance and plant–soil feedback remains unclear. This study investigated changes in soil properties across topsoil (0–20 cm) and subsoil (20–40 cm) in primary L. barbarum cultivation regions of northwest China, evaluating seedling growth and plant–soil feedback through pot experiments. Results revealed significantly higher fresh shoot weights in seedlings cultivated in topsoil compared to subsoil, with plant–soil feedback showing an inverse trend. Redundancy analysis indicated positive correlations between both fresh weight and plant–soil feedback with electrical conductivity and dissolved nitrogen content, while negative correlations were observed with soil pH at both depths. Notably, dissolved organic carbon content negatively correlated with fresh weight and plant–soil feedback in topsoil, suggesting a potential relationship between continuous single-species plant litter input and soil sickness under monocropping conditions. These findings indicate that long-term input of a single plant litter type, rather than chemical fertilization, may primarily contribute to L. barbarum soil sickness in northwest China, providing valuable insights for developing sustainable cultivation practices for growing L. barbarum.

Effects of salt stress on the fruit and yield quality of some selected tomato (<i>Lycopersicum esculentum</i> L.) varieties.

The growth, production, and nutritional characteristics of crops are impacted by abiotic factors such as salinity stress. The study aimed to assess the impact of salt stress on the fruit and yield characteristics of three distinct tomato cultivars, namely Rio, Dan syria, and UTC. Salt solutions with varying concentrations of NaCl were created by dissolving NaCl in deionized water. Four treatments were established, consisting of solutions with salt concentrations of 0g/L (control, without salt), 0.5g/L, 1.0g/L, and 1.5g/L. Each treatment was reproduced three times. The NaCl solutions were administered with a frequency of 7 days. The data in the study underwent Analysis of Variance (ANOVA). Rio outperformed the other varieties in terms of fruit quantity, fresh fruit weight, and fruit pericarp thickness under high salt stress, closely followed by UTC variety. The study also found that Dan syria performed better than the other varieties in terms of fresh and dry weight of shoot, as well as fresh weight of root, under mild and extreme salinity stress. However, Rio performed better than the other varieties in terms of dry weight of root under both mild and extreme salinity stress. The salt tolerance index of the Rio, UTC, and Dan Syria varieties under extreme salinity stress are 46.79%, 20.64%, and 34.70% respectively. This indicated that the Rio variety is the most salt-tolerant of the three types, with Dan Syria variety coming close.

Association mapping unravels the genetic basis for drought related traits in different developmental stages of barley

Drought stress significantly reduces crop yields at all stages of plant development. Barley, known for its abiotic-stress adaptation among cereals was used to examine the genetic basis of drought tolerance. A population of 164 spring barley lines was subjected to polyethylene glycol (PEG) induced drought stress during germination and seedling development. Six traits were measured, including germination percentage and rate, seedling length and weight, and root-to-shoot ratios. Seedling area, volume, and root and shoot diameter was acquired with a flatbed scanner. This population was also subjected to short-term drought during the heading stage in the greenhouse. Root and shoot weight and grain yield data were collected from well watered and droughted plants. Significant variation within traits were observed and several of them exhibited strong correlations with each other. In this population, two genotypes had 100% germination under PEG-induced drought and drought tolerance throughout the heading stage of plant development. A genome-wide association scan (GWAS) revealed 64 significant marker-trait associations across all seven barley chromosomes. Candidate genes related to abiotic stress and germination were identified within a 0.5Mbp interval around these SNPs. In silico analysis indicated a high frequency of differential expression of the candidate genes in response to stress. This study enabled identification of barley lines useful for drought tolerance breeding and pinpointed candidate genes for enhancing drought resiliency in barley.

Bacillus endophytic strains control Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici in tomato cv. Perinha.

Fusarium wilt is one of main phytopathology attacking tomato (Solanum lycopersicum L.) plantations in Brazil. Plant rhizosphere and endophytic beneficial microorganism are well known as plant growth promoters and biocontrol agents. The present study aims to evaluate the potential of different Bacillus strains as biocontrol agent to Fusarium oxysporum f. sp. lycopersici Race 3 strains; and also as plant growth promoting bacteria on Solanum lycopersicum cv Perinha. Different in vitro and greenhouse experiments were carried out to evaluate the direct and indirect bacterial-fungus antagonism, and they inoculation effects on plant traits. In vitro direct, metabolites, and volatile antagonism analysis demonstrated that B. toyonensis BR 10491(FORT 02) presented a broad antagonism to all tested race 3 FOL strains while B. megaterium BR 10466 (FORT 12), B. aryabhattai BR 10494 (FORT 25), B. stratosphericus BR 10438 (FORT 29) and B. cereus BR 10493 (FORT 113.1) strains showed significant antagonistic activity for at least two applied methods. Greenhouse pot experiments demonstrated a significant BCA effect of FORT 113.1 and FORT 02 against FOL Race 3 Fus 1302 strain during different tomato development stages (seedling, vegetative, and reproductive). Bacillus cereus (FORT 113.1) showed significantly higher shoot and height fresh weight, Chlorophyll a and Chlorophyll b content, stomata conductance, water use efficiency, and also a lower xylem infection percentage during vegetative and reproductive stages. Antioxidant enzymatic components analysis demonstrated a synergic effect of Fusarium and Bacillus inoculation, leading to a higher superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) activity. In conclusion, the results suggest that strain FORT113.1 could be considered as a good candidate for production of new biofungicide with high potential to augment the existing biocontrol strategies.

Enhancing Iron and Zinc Uptake in Spring Wheat Through Commercial Arbuscular Mycorrhizal Fungi Inoculation under Different Soil Phosphorus Addition Levels

Improving the concentrations and bioavailability of micronutrients, especially iron (Fe) and zinc (Zn), in crop grains is important to alleviate their deficiencies in humans. Inoculating crops with arbuscular mycorrhizal fungi (AMF) can potentially enhance soil nutrient supply and crop yield, but the effectiveness is influenced by soil factors, particularly soil phosphorus (P) availability. A greenhouse pot experiment was conducted to evaluate the effect of a commercial AMF product on spring wheat (Triticum aestivum L.) yield and grain concentrations of Zn and Fe under different soil P addition levels (0, 5 and 20 mg P kg-1 dry soil). Results showed that AMF inoculation significantly increased root colonization rate of wheat across all P addition levels. Wheat growth, as evidenced by dry weights of shoot and grain, was significantly enhanced by AMF and high P addition treatments. AMF inoculation did not affect grain Zn concentration, but significantly increased grain Fe concentration compared to the un-inoculated control. As expected, P addition resulted in a significant reduction in grain concentrations of Fe and Zn, primarily due to a growth dilution effect. An integrated analysis using the radar plot concludes that AMF inoculation is most effective in increasing crop yield and grain micronutrient concentrations when soil P levels are low. Importantly, while adequate P supply is crucial for maintaining crop productivity, it may decrease grain micronutrient availability without complementary strategies.

Daily Light Integral and Far-Red Radiation Influence Morphology and Quality of Liners and Subsequent Flowering and Development of Petunia in Controlled Greenhouses

Petunia stands as the top-selling bedding plant in the U.S., and improved lighting control in greenhouses holds the potential to reduce crop production time and optimize crop quality. This study investigated the impact of four distinct daily light integral (DLI) conditions with and without supplemental far-red (FR) radiation on the growth of petunia liners and subsequent development of finish plants. Two experiments were conducted in spring (9 April to 18 June 2021) and winter (28 October 2021 to 6 January 2022). Petunia cuttings were rooted in a common environment and then transferred to four greenhouse sections with different DLI treatments: 6, 9, 12, and 15 mol·m−2·d−1 for four weeks. Within each DLI condition, half of the plants were exposed to 28 μmol·m−2·s−1 supplemental FR radiation for 16 h daily (equivalent to 1.61 mol·m−2·d−1 light integral). The number of flower buds and open flowers were tracked daily. Representative liners were destructively harvested and evaluated after four weeks of lighting treatments. The remaining plants were transplanted and moved to a common DLI condition of 15 mol·m−2·d−1 for an additional three weeks before being destructively harvested and evaluated as finish plants. The primary finding reveals the promoting effect of DLI on flowering, branching, morphology, and biomass accumulation of petunia liners, with many effects persisting into the finish stage. A threshold DLI of 9 mol·m−2·d−1 was identified, as lower DLI (6 mol·m−2·d−1) resulted in extensive stem elongation, rendering the plants unmarketable. Higher DLI levels were found to be optimal in terms of flowering and morphology. Supplemental FR accelerated flowering by up to three days in the summer experiment and up to 12 days in the winter experiment. However, FR had limited impact on the number of flower buds and open flowers, branching, and shoot and root weight of the finish plants. Interactions between DLI and FR were observed on some parameters, whereby FR effects were more pronounced under lower DLI. Overall, both higher DLI and supplemental FR exhibited beneficial effects, but DLI had a more pronounced effect. Thus, DLI during petunia liner production appears more important than adding FR. This study well simulated the commercial propagation and production of petunia plants, providing practical insights for decision-making regarding lighting strategies.