Maximum Root Length Research Articles

Effect of Plant Density on Growth and Bioactive Compounds in Salvia miltiorrhiza

Danshen (Salvia miltiorrhiza) is an herbaceous plant widely used in the pharmaceutical industry. However, the majority of medicinal plants utilized in the US are imported, posing challenges such as fluctuations in bioactive compound concentrations and insufficient supply to meet demand. Determining the optimal plant density is a key management decision for danshen production. This study aimed to investigate the effects of different plant densities on the growth and bioactive compound content of danshen cultivated in Mississippi. A field experiment was conducted to investigate the effects of different plant densities on individual plant growth, photosynthesis, and the content of bioactive components in danshen in 2020 and 2021. Six plant densities were designed: 30 × 20 cm (between row spacing × within row spacing), 30 × 30 cm, 30 × 40 cm, 45 × 20 cm, 45 × 30 cm, or 45 × 40 cm. A plant density of 45 × 40 cm resulted in danshen plants exhibiting the highest Plant Growth Index (PGI), SPAD, root number, shoot number, shoot fresh and dry weight, maximum root diameter, maximum root length, net photosynthesis, intracellular CO2 concentration, tanshinone I, and cryptotanshinone, regardless of year. Plants spaced at 45 × 30 cm had similar root fresh weight, root dry weight, and tanshinone IIA and salvianolic acid B levels compared with plants grown at the 45 × 40 cm spacing, and both were significantly higher than other densities.

Vegetative propagation of Phytolacca acinosa Roxb. by rhizome cuttings: a step towards conservation and cultivation approach

IntroductionPhytolacca acinosa Roxb. is a highly valuable multipurpose herb native to the Himalayan region. Unsustainable harvesting of this species due to its diverse uses has resulted in a rapid decline in its population across natural habitats, thereby necessitating its propagation and conservation. To overcome this challenge, the potential of P. acinosa rhizomes for ex situ regeneration was evaluated.MethodsThe current study aims to develop a standard propagation protocol for P. acinosa. Rhizome cuttings derived by splitting whole rhizomes were used to study the effect of various hormones and soil compositions on their sprouting and growth performance.ResultsSoil compositions SC10 and SC5 consisting of soil, sand, pebbles, and vermicompost (1:1:1:1) and soil, sand, and vermicompost (1:1:1), respectively, were the most suitable compositions for the optimum growth of this species. The rhizome segments treated with GA3 (150ppm) induced the highest sprouting percentage (91.67%), with a minimum sprouting time of 23.25 days. The maximum root length (9.25 cm), shoot length (16.5 cm), and leaf number (11.25) were recorded for GA3 (150ppm) treated rhizome cuttings.ConclutionsOverall, the results of the present study helped in establishing a cost-effective, rapid, efficient, and simple mass propagation method for the target species. The results of this study will serve as a guide for the large-scale cultivation, effective conservation, and sustainable utilization of this economically valuable medicinal herb.

Characterization of Rhizobia Isolated from Tigray Soil and Assessment of Their Effect on Germination and Seedling Vigor of Wheat and Field Pea

Nowadays, the inoculation of plant growth-promoting rhizobia in leguminous and nonleguminous crops is given great emphasis as it improves germination and seedling vigor, resulting in increased yields. In this study, 32 rhizobia isolates were obtained from five different sampling sites in Tigray, Ethiopia. Based on morphological, biochemical, and confirmatory tests, including sugar fermentation, the isolates were identified as belonging to the rhizobia genera. In vitro assessment of plant growth-promoting properties revealed that all isolates produced indole-acetic-acid, ammonia, and solubilized phosphate, except TA8, which did not solubilize phosphate. Only 3 isolates (TA1, TA2, and TA8) produced hydrogen cyanide, so they can be used as biocontrol agents. Nineteen isolates showed a growth reduction activity against Fusarium oxysporum, with a percent inhibition range of 34.2%–65.8%. All isolates tolerated a pH range of 4.0–9.0. The isolates showed growth variations in various temperatures and salt concentrations. A few isolates were tolerant up to 45°C temperature and 6% (w/v) CaCl2 and NaCl concentrations. Inoculation of the isolates to wheat seeds increased seed germination, seedling shoot/root length, and seedling vigor index compared to the positive and negative controls. Isolates KO3, KO4, ME3, and TA5 increased seed germination by 4%. KO1 (11.60 cm) and TA7 (11.70 cm) showed a significantly enhanced shoot length, and ME3 showed a maximum root length (13.90 cm). SH1, KO2, and the positive control showed a significant (P≤0.05) increase in pea seed germination (by 20%) compared to the negative control. The positive control had the longest field pea shoot (5.70 cm), and isolate TA9 had the longest field pea root (5.32 cm) compared to the negative control. Generally, the wheat and field pea seedlings responded differently to the inoculation of different isolates. This study shows that Tigray soils harbor a variety of rhizobia species, which can be used as plant growth-promoting and biocontrol agents.

Boosting Capsicum annuum Growth Through Non-native Endophytic Bacterial Consortium

Abstract Organic and natural sources of bio-stimulant have a great expectancy to boost green agriculture practices for sustainable, safe, and smart cultivation of crops. In that regard, beneficial endophytic bacteria have great potential. They have unique features in promoting plant growth by colonizing and establishing well in plant roots. In this study, endophytes isolated from the roots of moringa, neem, sesbania, and chilli were screened for crop’s growth-enhancing activities, such as phosphorus (P) solubilization, 1-aminocyclopropane-1-carboxylic-acid deaminase (ACC deaminase) production, and indole-acetic acid (IAA) production. The phosphorus solubilization, indole-acetic acid production, and ACC deaminase production values fall in the range of 55–88 ppm, 20–164 ppm, and 0.317–0.375 mM, respectively. Chilli seeds’ three highest vigor index (VI) values were attained by MR10 (12,457 VI), MR3 (9450 VI), and MR13 (8730 VI). MR13 showed the highest seed germination energy (221%), followed by MR1 (178%) and MR3 (156%). The promising endophytes were tested on chilli seedlings as single and mixed inoculum treatments to study the efficiency of root colonization. Mixed cultures containing CKR8 and MR13 exhibited the highest seedling height (17.0 cm), followed by MR13, MR10, and MR13 (16.8 cm) compared to the control (12.6 cm). A single culture of MR10 (109.0 g and 13.53 cm2) and a mixed culture of MR10 and MR13 (100.0 g and 13.09 cm2) showed the maximum root length and surface area, respectively. The highest relative chlorophyll content was recorded by MR10 and MR13 (40.3 SPAD value), followed by MR13, MR3, and CKR8 (36.8 SPAD value). The non-native endophytic bacteria, MR13, Streptomyces panaciradicis (GenBank accession no. OM001090), and MR3, Bacillus subtilis (GenBank accession no. OM714810), could colonize the roots and improve the growth of chilli at the seedling growth stage. Graphical Abstract

Effect of Bio-Priming with Isolates of Fungal Bio Agents on Morphological Attributes and Growth Parameters of Chickpea

Chickpea (Cicer arietinum L.) is one of the most important pulse crops of India. Chickpea is one of the major and abundant sources of protein among pulses; production of chickpea is very low all over the worldwide due to several biotic and abiotic stresses. Biotic stress diseases are the major problems. Chickpea wilt caused by Fusarium oxysporum f. sp. ciceri has been considered as devastating one to cause up to 10 per cent loss in yield every year. For eco-friendly and sustainable management of the disease, six isolates of two fungal bioagents Trichoderma harzianum and Trichoderma viride were evaluated for their antagonistic efficacy on colony growth by dual culture plate method. The results showed that the bio-agents suppressed the colony growth ofpathogen which ranged between 70.80-59.29%. Isolates of T1 [Trichoderma harzianum (KN)] 70.80% was found very effective antagonistic effect compare to all treatments and control followed by T2 [Trichoderma harzianum (VN) which inhibited 68.80%, T3 [Trichoderma harzianum (UNN) 66.45% and T4 [T. viride (FBD)] 63.58% mycelia growth of pathogen and so on. The result of seed treatment in vivo condition showed that T1 found highest germination percent among all the treatments with a value of 85.71%. In all the treatment, substantially boosting the morphology of chickpea against control, the maximum number of branches was recorded in T1, with value of 12 and maximum root length was 13.33 cm with increase 81.85% over the control. In the yield parameter, the highest number of pods was found in T1 with 41 pods, followed by T2 and T3 with 37 and 36 pods, respectively. Result of the study show that bio-agents significantly reduced the wilt incidence, treated plants subsequently significantly increased germination percentage, morphological parameters and yield parameters over the non-treated plants. .

GROWTH AND YIELD RESPONSES OF RED AMARANTH TO LOCALLY SOURCED LIQUID MANURE

The experiment was conducted at Horticultural farm, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh during the period of September to November 2023. The experiment was laid out with single factor experiment using a completely randomized design with three replications to study the Growth and Yield responses of Red Amaranth (Amaranthus cruentus L) to liquid manure. The treatments under this study were; T1: Control (Only Water), T2: Vermi Tea; T3: SAU- MLM, T4: SAU-NLM, T5: SAU-PLM. Significant variation of growth and yield parameters were found among the treatments. Among the treatments. The tallest plant (44.3 cm), maximum root length was (13.3cm), maximum leaf area (38.2 sq. cm), maximum leaf number (14.0), maximum fresh weight per plant (22.1g), highest weight of plants per 506.25 sq. cm (274.9 g) and highest yield per ha (54.3 ton) was found in T5 while shortest plant (25.1 cm, minimum root length (4.8cm), minimum leaf area (16.4 sq. cm), minimum leaf number (8.6), minimum weight of plants/506.25 sq.cm. (77.5 g) and the lowest yield per ha (15.6 t) was found in T1 at final harvest (30 days after showing). Considering the overall analysis, it becomes evident that T5 consistently exhibits superior outcomes when compared to the other treatments. The superior performance of T5 suggests that it could be the optimal choice for maximizing agricultural productivity while maintaining a focus on human well-being and environmental sustainability. This treatment option not only results in higher yields, indicating potential economic benefits, but it also contributes to the overall safety and health considerations for individuals involved in the agricultural processes.

Bending performance changes during prolonged canine eruption in saber-toothed carnivores: A case study of Smilodon fatalis.

The canine of saber-toothed predators represents one of the most specialized dental structures known. Hypotheses about the function of hypertrophied canines range from display and conspecific interaction, soft food processing, to active prey acquisition. Recent research on the ontogenetic timing of skull traits indicates the adult canine can take years to fully erupt, but the consequences of prolonged eruption on inferences of canine functional morphology are missing from current discourse and have not been quantified. Here I evaluate hypotheses about adult canine bending strength and stiffness, respectively, during eruption in the felid Smilodon fatalis. Simulated eruption sequences of three adult canines were generated from specimen models to assess shifting cross-sectional geometry properties, and bending strength and stiffness under laterally directed loads were estimated using finite element analysis. Consistent with beam theory expectations, S. fatalis canine cross-sectional geometry is optimized for increased bending strength with increased erupted height. However, canine cross-sectional geometry changes through eruption exaggerate rather than minimize lateral deflection. Spatial constraint for maximum root length from adjacent sensory structures in the maxilla and the recently identified universal power law are hypothesized to limit the growth capacity of canine anteroposterior length and, consequently, maintenance of bending stiffness through eruption. Instead, the joint presence of the deciduous and adult canines for >50% of the adult canine eruption period effectively increases canine mediolateral width and brings bending strength and stiffness estimates closer to theoretical optima. Similarly prolonged retention of deciduous canines in other sabertooths suggests dual-canine buttressing is a convergently evolved strategy to maximize bending strength and stiffness.

In vitro regeneration of exotic fruit dragon (Hylocereus undatus) from stem fraction

Hylocereus undatus, commonly known as dragon fruit, is one of the most popular exotic fruits due to its high quality and market value. This fruit is facing different constraints, such as loss of seed viability and various diseases that affect production because the seed and cutting methods are followed to create a new generation. In vitro plant regeneration is a promising technique to overcome these barriers with explants. An efficiency of this protocol was established in dragon fruit using MS + 2.0 mg/L BA + 2.0 mg/L Kin. with explants, stem fraction. Eighty percent explants were responded for shoot initiation treated with 2.0 mg/L BAP in combination with 2 mg/L Kin. The highest number of shoots and the maximum shoot lengths were observed in this medium inoculation after 90 days. Shoots were transferred to media containing ½ strength of MS with root induced PGRs. Ninety percent of the in vitro raised shoots were responded for rooting treated with 2.5 mg/L IBA inoculation after 30 days. The highest number of roots and the maximum root lengths were recorded at 2.5 mg/L IBA. The response of inoculated explants or in vitro raised shoots were positively correlated with the number of shoots and roots respectively. The average shoot and root lengths were negatively correlated with each other resulting in root lengths increasing by decrease of shoot lengths. The healthy shoots with well rooted plantlets were transferred to natural condition where about 80% plantlets were found to be acclimatized.

Seed germination and vegetative and in vitro propagation of Hieracium lucidum subsp. lucidum (Asteraceae), a critically endangered endemic taxon of the Sicilian flora.

Hieracium lucidum subsp. lucidum is a critically endangered endemic taxa of the Sicilian flora. It is a relict of the Tertiary period surviving on the cliffs of Monte Gallo (NW-Sicily). This research focused on finding the best protocols for seed germination and vegetative and in vitro propagation to contribute to ex situ conservation. Seed germination tests were carried out using constant temperatures of 15 °C, 20 °C and 25 °C in continuous darkness and an alternating temperature of 30/15 °C (16 h/8 h, light/dark). The seeds had no dormancy, and a high germination capacity (70-95%) was obtained at all tested thermoperiods. The possibility of vegetative propagation of the taxon was evaluated through the rooting capacity of stem cuttings treated or not treated with indole-3-butyric acid (IBA). All cuttings were treated with IBA rooted within 2 months, while only 50% of the untreated cuttings were rooted within a longer time. An efficient protocol for rapid in vitro propagation from leaf portions was developed. The response of explants was tested on hormone-free Murashige and Skoog (MS) basal medium and MS enriched with different types of cytokinins: 6-Benzylaminopurine (BAP) and meta-Topolin (mT) in combination with naphthaleneacetic acid (NAA) and 2,4-Dichlorophenoxyacetic acid (2,4-D) at the same concentration. The combination of mT (2 mg L-1) and 2,4-D (1 mg L-1) in the medium was the most effective and showed the highest percentage of callus induction and the mean number of regenerated shoots. The maximum rate of root regeneration and the maximum number and length of roots were obtained on hormone-free MS and MS enriched with IBA at concentrations of 1 mg L-1. From the results obtained, it can be concluded that H. lucidum subsp. lucidum can be successfully propagated using one of the tested techniques, subject to the availability of the material for reproduction.

Effects of bio consortium for the management of collar rot (Sclerotium rolfsii) disease of chickpea in vivo condition

A experiment was conducted in 2019-20 Rabi cropping season to obtain information on the incidence of chickpea diseases. The investigation was entitled effects of bio consortium for the management of collar rot (sclerotiumrolfsii) disease of chickpea in vivo condition was conducted, Department of Plant pathology JNKVV. The experiment was laid out in Completely Randomized Design (CRD) concept comprising nine treatment combinations with three replications in net house condition.Effect of bio consortium against collar rot (Sclerotiumrolfsii) disease incidence on variety JG-12: Among the treatments minimum germination per cent 76.67 per cent was observed in T8. Maximum pre-emergence mortality 23.33 per cent was recorded in T8, Maximum disease incidence of 24.48 and 22.77 per cent was observed in T8 and minimum mortality 17.37% was recorded in T6. Effect of bio consortium on collar rot (Sclerotiumrolfsii) disease and phenotypic parameters on variety JG-12: Among the treatments minimum germination per cent 78.60 per cent was observed in T8, Maximum shoot height 24.33, 22.07, 20.07, 19.27, 16.37, 15.67, 14.23 and 13.30 cm were recorded in T6, Maximum root height 10.37 was recorded in T6, Maximum vigour index per cent of 3,274.21 was recorded in T6. Effect of bio consortium on collar rot (Sclerotiumrolfsii) disease incidence on variety JG-14: Among the treatments minimum germination per cent 77.78 per cent was observed in T8, Maximum pre-emergence mortality 22.22 per cent was recorded in T8, Maximum disease incidence of 24.27 per cent was observed in T8, minimum mortality 16.24 per cent was recorded in T6 (T. viride + T. harzianum + P. fluorescens).Effect of bio consortium on collar rot (Sclerotiumrolfsii) disease and phenotypic parameters on variety JG-14. Among the treatments minimum germination percent 80.68 per cent was observed in T8, Maximum shoot height 26.37 was recorded in T6, Maximum root length 11.53,was recorded in T6, Maximum vigour index percent of 3,658.07 was recorded in T6.

Molecular, morphological, and biomolecular characterization of ethyl methanesulfonate-induced mutations in Aerides odoratum, an orchid

Aerides odoratum L. is a medicinal and ornamental orchid of the Eastern Himalayas, India. Its uses in pharmacology are nought because of its rare occurrence, longer life cycle, and lack of artificial methods for large-scale propagation. Protocorms (60 days old) were treated with various concentrations of ethyl methanesulfonate ranging from 0.025% to 0.5% for different durations (2, 5, 7, and 10 days) during M0 (treatment) in vitro generation. The survival of these protocorms and the generation of shoots and roots were noted. 10–20 plantlets of each treatment showing variation in the number and weight of shoots in M0 generation (treatment generation) were maintained for three subsequent generations. M3 (third generation) axenic plantlets were hardened in the orchidarium with a 75% survival frequency. Four mutant lines (M3V1–M3V4) were established based on RAPD analysis of the leaf DNA of 300-day-old plants. M3V-1 was noted as the best among all mutant lines based on morphological analysis, whereas M3V-2 was noted as the most superior in terms of having the highest quantity of osmolytes, pigments, stomata, and phenol. M3V-3 had maximum root length, leaf breadth, and carotenoids. M3V-4 showed the viridis chlorophyll spectrum as the most distinguishing factor. Hence, this standardized protocol can be used for the genetic improvement of A. odoratum.

Otimização da tecnologia de micropropagação clonal de variedades ornamentais de rosas ‘Dream Come True’ e ‘Full Sail’

Abstract The rose is the most important ornamental and floral crop, as well as a valuable aromatic and medicinal plant. For accelerated production of planting material, clonal micropropagation is used. There are problems in obtaining an aseptic culture and the peculiarities of plant cultivation at different stages, depending on the variety. It is necessary to develop and optimize the technological cycle of cultivation in in vitro culture. The results showed that the highest viability of rose explants obtained from lateral buds was noted by sterilization with 0.2% silver nitrate solution of and 5% Lysoformin 3000 with an exposure of 15 minutes (82%-95%); the highest viability of explants obtained from etiolated shoots was observed when sterilized with 0.2% silver nitrate solution with an exposure of 10 minutes and 5% Lysoformin 3000 with an exposure of 15 min (82%-100%). The maximum length of the micro-shoots was noted in the ‘Dream Come True’ variety on a QL (Quoirin and Lepoivre) nutrient medium (on average 21.2 cm), in the ‘Full Sail’ variety - on a ½ QL medium (on average 24.9 cm). An increase in the concentration of 6-BAP from 0.5 to 1.0 mg L-1 in the nutrient medium contributed to an increase in the number of micro-shoots (by 1.7-1.9 times). The maximum root length was noted on the nutrient medium ½ QL (on average 88.7-95.3 cm). An increase in the concentration of IAA from 0.5 to 1.0 mg L-1 in the nutrient medium contributed to an increase in root length by 1.4-1.8 times. The protocol developed in this study allows to propagate these two varieties in vitro and produce a large number of plants.

Comparative Evaluation of Modified Kvaal’s Formula and Coronal Pulp Cavity Index in the Pune Population – A Cone-beam Computed Tomography-based Retrospective Study

ABSTRACT Introduction: The uniqueness of the human dentition serves its wide acceptance in the identification of individual in forensic science. Aim and Objectives: To estimate the accuracy of age by using modified Kvaal’s formula and coronal pulp cavity index (CPCI) and compare the standard error and establish the technique among the Pune population. Materials and Methods: Four hundred cone-beam computed tomography (CBCT) scans were randomly selected with satisfying the established criteria. The second premolar was included in the study and the maximum length of tooth, root, and pulp was measured using modified Kvaal’s method and CPCI by using Planmeca CBCT machine with Romexis-three-dimensional imaging software. Results: The results were analyzed using the Chi-square test and ANOVA. Modified Kvaal’s formula was found to be the better followed by CPCI in the estimation of age among Indians with lesser error in prior. Conclusion: Modified Kvaal’s formula is precise, noninvasive, and most reliable biomarker for age estimation than tooth-coronal index.

Assessment of the growth of forest seedlings in new substrates from wood waste and sewage sludge

The morphological parameters of Scots pine (Pinus sylvestris L.) seedlings grown in experimental substrates made from sewage sludge and pine shavings (substrate 1), and pine bark (substrate 2) were studied. The production time of the substrate varied: substrate 1 – 2 months, substrate 2 – 1.5 years. Seedlings of 2-year-old pine were selected for research. To analyze the parameters of seedlings, average values and square deviations were calculated, reliability was determined by Fisher and Student tests. To analyze the length of the root system, one-way analysis of variance was used in MS Excel. For roots of the 2nd order and total root length, the observed values of Fisher’s criterion are: 15.42 and 11.27, which exceeds the critical value of 3.18 and indicates a significant difference between seedlings grown in the manufactured substrates. The diameter of the root collar of seedlings grown in peat exceeded that of seedlings grown on substrate 2 by 13%, and in substrate 2 by 4.4%. Maximum root length for seedlings from substrate 1. Substrates from wood waste and sewage sludge can replace fossil peat without losing the quality of growing seedlings and contribute to the emergence of improved quality characteristics of seedlings.

Impact of Seed Priming and Growing Media on Germination and Seedling Growth of Bitter Gourd

Aims: The aim of this study was to determine the suitable growing media and priming treatments for seed germination and seedling growth of bitter gourd (cv. BARI hybrid Korola 2).
 Study Design: The experiment was set up in a completely randomized design (CRD) with sixteen treatments, each containing fifteen seedlings.
 Place and Duration of the Study: The experiment was conducted on Horticulture farm at Sher-e-Bangla Agricultural University; Dhaka, Bangladesh from March to April 2021.
 Methodology: Four seed priming treatments were used in the experiments: T0: Seed soak in distilled water for 12 h (control), T1:Hot water treatment (450C for 5 min), T2: Poly ethylene glycol (PEG) 6000 (5%), T3: Sodium chloride solution (NaCl) (2%) soak for 12h and four growing media viz.,M0: soil + cow dung (1:1), M1: soil + cow dung + vermicompost (1:1:1), M2: soil + cow dung + sawdust (1:1:1), M3: soil + cow dung + cocopeat (1:1:1).
 Results: The maximum germination percentage (100%), highest shoot (21.00 cm) and root length (12.83 cm), seed vigor index (3383.3) was recorded in T2M3 treatment. However, the maximum photosynthetic pigment (30.31 mg/g), relative water content (96.99%) and shoot (3.53g) and root fresh weight (0.47 g) was found in T2M1 treatment.
 Conclusion: It can be concluded that soil + cow dung + cocopeat (1:1:1) with PEG 6000 (5%) is the best treatment for bitter gourd seed germination, while soil + cow dung + vermicompost (1:1:1) with PEG 6000 (5%) is better for vigor and healthy seedlings.

Root attributes governing drought stress adaptation and the associated molecular markers in chromosome segment substitution lines in rice (Oryza sativa L.)

The wild relatives of cultivated rice offer crucial resistance genes for combating stresses like drought. Developing rice varieties with drought tolerance is possible through chromosome segment substitution lines (CSSLs), which blend the genetic background of a high-yielding parent with specific chromosome segments from a donor parent. This study aimed to study the effect of drought stress on various root traits of chromosome segment substitution lines (CSSLs) and their relationship with specific molecular markers. Ninety-six genotypes, including 80 chromosome segment substitution lines (Curinga x O. rufipogon and Curinga x O. meridionalis), 9 New Rice for Africa (NERICAs) and 7 controls were grown in Basket and PVC pipe methods for phenotyping different root traits. Under drought stress (DS), MER16, MER20, RUF10, RUF16, RUF44, NERICA1, and NERICA3 showed superior performance for most of the root traits. These evaluations were supplemented with association analysis of 17 root trait-linked simple sequence repeat (SSR) markers with root phenotypic traits. The marker RM201 is strongly associated with multiple root traits, found to be independent of three growth conditions (well-watered “WW” under Basket, WW condition and DS conditions under PVC pipe). The marker RM316 is associated with root volume, and the marker RM7424 and RM1054 show maximum root length. In conclusion, these markers can be used in marker-assisted breeding programs, and the lines carrying them can be used as parental lines in variety-development programs for drought tolerance.

Biofortified Vermicompost Mediated Induced Resistance Response in Tomato against Fusarium oxysporum f. sp. lycopersici

Tomato (Solanum lycopersicum) is a widely cultivated and versatile fruit. Tomato production faces various constraints, both biotic and abiotic stresses. Fusarium wilt, caused by the soil-borne fungus Fusarium oxysporum f. sp. lycopersici, is a devastating disease that affects tomato plants worldwide, causing significant economic losses in tomato cultivation. Inthis study the potential use of biofortified vermicompost for wilt management was investigated. The biological control agents viz. Trichoderma harzianum, Pseudomonas fluorescens and Bacillus subtilis were used to fortified the vermicpompost. The study monitored various antioxidants, plant growth indicators, and disease rates across designated treatments at different intervals. The findings revealed substantial differences: tomato plants treated with biofortified vermicompost showed notable reductions in disease occurrence, improved growth, increased yields, and heightened antioxidant activity compared to the control. Among these treatments, the most remarkable outcomes were observed in plants treated with T. harzianum fortified vermicompost, exhibiting the highest recorded values across the parameters studied. Data revealed that the Tomato plants treated with vermicompost fortified with Trichoderma showed maximum root length (14.95 cm) after 15 days of sowing followed by T-2 (11.25 cm) and T-3 (9.85 cm). Maximum dry weight was observed in plants treated with vermicompost fortified with Trichoderma. Maximum PAL, PO and PPO activity was recorded in leaves from plant grown in vermicompost fortified with T. harzianum (T1) at 48 h followed by T2, T3 and T4. The findings revealed tomato plants treated with biofortified vermicompost showed notable reductions in disease occurrence, improved growth, increased yields, and higher accumulation of defense enzyme activity compared to the control.

A Type A Response Regulator Is Involved in Growth in Salix Matsudana Koidz

The cytokinin signaling pathway is important for plant growth and development. To understand the regulatory process, a type A response regulator, SmRR5, in Salix matsudana Koidz., was characterized and functionally analyzed. Gene expression tests showed that SmRR5 was distinctly higher in the leaves and roots of the fast-growing S. matsudana variety 9901 than in those of the slow-growing variety Yanjing (YJ). The transcript abundance was highest in the meristem zone (MEZ), followed by the elongation zone (EZ) and maturation zone (MAZ) in 9901 roots, but it was identically low in YJ roots. Overexpression of SmRR5 in tobacco plants significantly improved plant height, maximum root length (MRL), lateral root number (LRN), fresh weight (FW), dry weight (DW), and flowering time compared with wild-type plants. Transcript profiling revealed that multiple genes associated with flowering (SWEET1, FPF1, and COL12), plant growth (YUCCA8, PIN5, and ARF9a), and adventitious root (AR) formation (Hox3, MYC2, and AGL46) were highly expressed in the overexpression of leaves and roots. Thus, SmRR5 effectively facilitated plant growth and development.

An appropriate ammonium: nitrate ratio promotes the growth of centipedegrass: insight from physiological and micromorphological analyses.

Reasonable nitrogen fertilizer application is an important strategy to maintain optimal growth of grasslands, thereby enabling them to better fulfil their ecological functions while reducing environmental pollution caused by high nitrogen fertilizer production and application. Optimizing the ammonium (NH4 +):nitrate (NO3 -) ratio is a common approach for growth promotion in crops and vegetables, but research on this topic in grass plants has not received sufficient attention. Centipedegrass, which is widely used in landscaping and ecological protection, was used as the experimental material. Different NH4 +:NO3 - ratios (0: 100, 25:75, 50:50, 75:25, 100:0) were used as the experimental treatments under hydroponic conditions. By monitoring the physiological and morphological changes under each treatment, the appropriate NH4 +:NO3 - ratio for growth and its underlying mechanism were determined. As the proportion of ammonium increased, the growth showed a "bell-shaped" response, with the maximum biomass and total carbon and nitrogen accumulation achieved with the NH4 +:NO3 - ratio of 50:50 treatment. Compared with the situation where nitrate was supplied alone, increasing the ammonium proportion increased the whole plant biomass by 93.2%, 139.7%, 59.0%, and 30.5%, the whole plant nitrogen accumulation by 44.9%, 94.6%, 32.8%, and 54.8%, and the whole plant carbon accumulation by 90.4%, 139.9%, 58.7%, and 26.6% in order. As a gateway for nitrogen input, the roots treated with an NH4 +:NO3 - ratio of 50:50 exhibited the highest ammonium and nitrate uptake rate, which may be related to the maximum total root length, root surface area, average root diameter, root volume, and largest root xylem vessel. As a gateway for carbon input, leaves treated with an NH4 +:NO3 - ratio of 50:50 exhibited the highest stomatal aperture, stomatal conductance, photosynthetic rate, transpiration rate, and photosynthetic products. The NH4 +:NO3 - ratio of 50:50 treatment had the largest stem xylem vessel area. This structure and force caused by transpiration may synergistically facilitate root-to-shoot nutrient translocation. Notably, the change in stomatal opening occurred in the early stage (4 hours) of the NH4 +:NO3 - ratio treatments, indicating that stomates are structures that are involved in the response to changes in the root NH4 +:NO3 - ratio. In summary, we recommend 50:50 as the appropriate NH4 +:NO3 - ratio for the growth of centipedegrass, which not only improves the nitrogen use efficiency but also enhances the carbon sequestration capacity.

Response of a submerged macrophyte (Vallisneria natans) to water depth gradients and sediment nutrient concentrations

Submerged plants constitute a vital component of shallow lake ecosystems, where water depth and sediment nitrogen‑phosphorus content are two key factors influencing their growth. This study focuses on Vallisneria natans and investigates the morphological and physiological changes of V. natans under the interaction of three water depth gradients and two different sediment nutrient levels. It explores the mechanisms through which varying sediment nutrient conditions under different water depths affect the growth of V. natans. The results indicate that both independent and interactive effects of water depth and sediment nutrient status significantly impact the morphology, antioxidant enzyme activity, and photosynthetic pigment content of V. natans, with water depth having a greater influence. To adapt to increased water depth-induced light stress, V. natans responds morphologically by increasing leaf length, leaf width, and decreasing maximum root length. Physiologically, it enhances its antioxidant regulation capacity and photosynthetic efficiency by increasing antioxidant enzyme activity, root vitality, and photosynthetic pigment content to counter weak light stress. However, these adaptations are insufficient to cope with excessively deep waters (200 cm). Sediment nutrient levels primarily control the growth of V. natans by affecting its root system. When sediment nitrogen and phosphorus content is lower, V. natans exhibits greater total root volume and surface area to enhance nutrient absorption efficiency. Water depth not only directly influences the growth of submerged plants but may also impact the migration and transformation of phosphorus in sediments, further exacerbating its effects on the growth of these plants, thus accelerating the regime shift of shallow lakes. Therefore, this study reveals V. natans' response strategies to varying water depths and sediment nutrient levels, determining suitable water levels and sediment nutrient conditions for its growth. These research findings provide a scientific basis for water level management and ecological restoration of submerged aquatic plants in shallow lakes.