Shoot Dry Weight Research Articles

Jasmonic Acid and Salicylic Acid improved resistance against Spodoptera frugiperda Infestation in maize by modulating growth and regulating redox homeostasis

Exploring host plant resistance and elevating plant defense mechanisms through the application of exogenous elicitors stands as a promising strategy for integrated pest management. The fall armyworm, a pernicious menace to grain crops in tropical and subtropical regions, stands as a formidable threat due to its capacity for devastation and a wide-ranging spectrum of host plants. There is no literature regarding artificially induced resistance in maize against fall armyworm (Spodoptera frugiperda) by exogenous application of phytohormones. The present investigation was performed to evaluate the role of jasmonic acid (JA) and salicylic acid (SA) on two maize hybrids namely FH-1046 and YH-1898 against fall armyworm. Results showed that plant height, biomass and lengths, fresh and dry weight of root shoot which decreased with armyworm infestation improved with phytohormonal application. JA treatment resulted in a higher increase in all attributes as compared to SA treatment. Improvement in relative water contents, photosynthetic pigments and pronounced levels of phenol and proline accumulation were observed in infested plants after JA treatment. Infested plants recovered from oxidative stress as JA application activated and increased the antioxidant enzyme activity of superoxide dismutase, peroxidase and polyphenol oxidase activity in both FH-1046 and YH-1898 . The oxidative stress reduction in infested plants after JA treatment was also evident from a fair decrease in MDA and H2O2 in both varieties. The SA and JA mediated genes expression was studied and it was found that in FH1046 maize cultivar, JA dependent genes, particularly marker genes PR1 and Lox5 were highly expressed along with TPS10 and BBT12. Whereas SPI, WRKY28, ICS and PAL were shown to be activated upon SA application. Evidently, both JA and SA elicited a robust defensive response within the maize plants against the voracious S. frugiperda, which in consequence exerted a discernible influence over the pest's developmental trajectory and physiological dynamics. A decrease in detoxification enzyme activity of the insects was observed after feeding on treated plants. Moreover, it was recorded that the survival and weight gain of FAW feeding on phytohormone treated maize plants also decelerated. In conclusion, FH-1046 was found to be more tolerant than YH-1898 against fall armyworm infestation and 1 mM JA was more effective than 1 mM SA for alleviation of fall armyworm stress. Therefore, it was inferred that phytohormones regulated redox homeostasis to circumvent oxidative damage and mediate essential metabolic events in maize under stress. To our current understanding, this study is the very first presentation of induced resistance in maize against S. frugiperda with the phytohormonal application (JA and SA).

Isolation and characterization of chromium-resistant bacteria and their effects on germination, growth, and Cr accumulation in Capsicum annum (L.) under Cr stress

Chromium (Cr) is a well-known environmental pollutant while less information is available on the role of Cr-resistant bacteria in the alleviation of Cr-stress in chili (Capsicum annum L.) plants. Effect of Cr-resistant bacterial strains on growth and Cr uptake by chili plants was investigated. The results revealed that Cr-stress showed a negative effect on germination, photosynthesis, and relative water content but the inoculation ameliorated the plant stress. Chromium-resistant bacterial strains enhanced the shoot and root growth (33% SL, 19.7% RL), shoot and root dry weight (35%, 32.9%), relative water content (32.25%), membrane stability index (46.52%) SPAD value (50.76%), Cr concentration in shoots and roots (19.87 and 18.52 mg kg−1), bioaccumulation and translocation factor (0.396 mgkg−1), and seedling vigor index (40.8%) of plants. Chromium-resistant bacterial strains enhanced the NPK uptake while reduced Cr uptake by plants. The morphological and biochemical examination of rhizobacterial strains (and NM28) resistant to Cr-stress revealed smooth, off-white colonies of bacteria composed of rod-shaped cells which are Gram positive in reaction while negative in catalase activity. High quantities of malic acid were produced by bacterial strains under study i.e. NM8 (926.12 μgmL−2) and NM28 (992.25 μgmL−2). These strains were identified as Bacillus cereus strain NM8 and Bacillus subtilis strain NM28 through 16S rRNA sequencing. Results showed that B. cereus strain NM28 is more effective than B. cereus strain NM8 in promoting the growth of Cr-stressed Chili that might be suitable to develop biofertilizer for sustainable production of vegetables under metal stress.

Biomass-derived carbon dots enhanced maize (Zea mays L.) drought tolerance by regulating phyllosphere microorganisms and ion fluxes

Enhancing crop drought tolerance is beneficial for increasing crop yield and ensuring food security. This study demonstrates that foliar application of biomass-derived carbon dots (Soy-CDs, 10 mg·L−1) can enhance the drought tolerance of maize, leading to an increase in fresh weight of maize shoots and roots (50.5 % and 54.9 %) and dry weight of maize shoots and roots (40.0 % and 37.7 %), respectively. Meanwhile, Soy-CDs altered the abundance of phyllosphere microorganisms (e.g. Proteobacteria, Deinococcus-Thermus, Verrucomicrobia, and Actinobacteria) of maize under drought stress, which enhanced the nitrogen fixation and stress resistance in maize leaves. Besides, Soy-CDs also promote Ca2+ influx and Na+ efflux in maize mesophyll cells under drought stress, facilitating the regulation of ion osmotic balance and contributing to the improvement of maize drought tolerance. Furthermore, Soy-CDs enhanced photosynthesis (55.3 %) of maize under drought stress, and the full life cycle study showed that Soy-CDs can promote the metabolism of maize kernels, ultimately improve the yield (40.5 %) and nutritional quality of maize. Therefore, this work discovers the enormous potential of biomass-derived carbon dots in improving drought resistance and quality of crop, which contributes to ensure food security.

Screening Cover Crops for Utilization in Irrigated Vineyards: A Greenhouse Study on Species' Nitrogen Uptake and Carbon Sequestration Potential.

This study examines the potential of 23 plant species, comprising 10 legumes, 9 grasses, and 4 forbs, as cover crops to enhance carbon (C) sequestration and soil nitrogen (N) in vineyards. After a 120-day evaluation period, cover crop biomass was incorporated into the soil, and grapevine seedlings were planted in its place. Among the established cover crops, the C input potential ranged from 0.267 to 1.69 Mg ha-1, and the N input potential ranged from 12.3 to 114 kg ha-1. Legume species exhibited up to threefold greater shoot dry weight (SDW) compared to grass species. Ladino white clover, Dutch white clover, and Clover blend were superior in SDW, total dry weight (TDW), total C content, and total N content. Legumes exhibited slightly higher root dry weight (RDW) than grasses, with the exception of Fall rye leading at 15 g pot-1, followed by Ladino white clover and Dutch white clover at an average of 12 g pot-1. Legumes, particularly clover blend and Alsike clover, displayed high shoot N concentration at an average of 2.95%. Root N concentration in Legumes (Fabaceae) were significantly higher at 1.82% compared to other plant families at 0.89%, while their root C/N ratio was lower at 18.3, contrasting with others at 27.7, resulting in a faster turnover. Biomass production exhibited a negative relationship (R2 = 0.51) with soil residual NO3-. Fall rye, Winfred brassica, and buckwheat had the highest N utilization efficiency (NUtE) values (ava. 121 g g-1). Alsike clover, Ladino white clover, and clover blend showed the highest N uptake efficiency (NUpE) values (ava. 75%). The Readily Available N (RAN) Reliance Index (RANRI) is introduced as a novel indicator for quantifying the extent to which a plant relies on RAN for its total N requirement. The RANRI value represents the percentage of the plant's total N sourced from RAN, ranging from 11% for legumes to 86% for grasses. This implies a substantial influx of nitrogen through a pathway independent of RAN in legumes. Grape shoot N concentration positively correlated with soil NO3- (R2 = 0.31) and cover crop C/N ratio (R2 = 0.17) but negatively correlated with cover crop TDW (R2 = 0.31). This study highlights legume plants as more effective in C and N assimilation during establishment but cautions about potential soil mineral N depletion before reaching their full biological N fixation capacity.

Amino acid‐based biostimulants and microbial biostimulants promote the growth, yield and resilience of strawberries in soilless glasshouse cultivation

AbstractIntroductionThe increasing demand for strawberries in the United Kingdom, valued for their flavour, nutrition and economic significance, presents challenges in maintaining consistent production, especially under various biotic and abiotic stress conditions. Traditional reliance on conventional agrochemicals to meet these demands is tempered by concerns about their health and environmental impacts, paving the way for eco‐friendly alternatives, such as biostimulants. However, their efficiency in commercial table‐top systems for June‐bearing and ever‐bearing strawberries under glasshouse conditions remains underexplored.Materials and methodsThis study investigated the efficiency of two commercial biostimulants in enhancing the growth, productivity and resilience of two strawberry varieties: ‘Malling Centenary’ (June‐bearer) and ‘Malling Ace’ (ever‐bearer) strawberry cultivars in a soilless hydroponic system within an unheated glasshouse. ‘Vitalnova Prime’ (VP), an amino acid and peptide‐based biostimulant derived from yeast, was applied every 2 weeks as a foliar spray (1 mL/L), whereas ‘Vitalnova Triboost’ (VT), a microbial inoculant with live cultures, was incorporated into the medium post‐transplanting (500 g/m3).ResultsVP significantly enhanced vegetative growth in both cultivars, resulting in substantial increases in number of leaves, crowns, crown diameter and shoot biomass accumulation compared to the control. VT also effectively improved multiple growth parameters compared to the control. Both biostimulants similarly improved crown formation and shoot dry weight in ‘Malling Centenary’. In terms of yield, both VP and VT increased yield in ‘Malling Ace’; notably, VP significantly enhanced the number of marketable fruits by 55% and average fruit weight by 56% compared to the control. Additionally, both biostimulants significantly reduced the occurrence of diseased fruits in both cultivars.ConclusionThis study demonstrates that biostimulants significantly enhance the growth, yield, and resilience of strawberries in soilless cultivation systems within unheated glasshouses. These findings suggest that biostimulants offer a sustainable and promising approach to addressing the increasing global demand for high‐quality strawberries.

Understanding the role of magnetic (Fe3O4) nanoparticle to mitigate cadmium stress in radish (Raphanus sativus L.)

Heavy metals stress particularly cadmium contamination is hotspot among researchers and considered highly destructive for both plants and human health. Iron is examined as most crucial element for plant development, but it is available in inadequate amount because they are present in insoluble Fe3+ form in soil. Fe3O4 have been recently found as growth promoting factor in plants. To understand, a sand pot experiment was conducted in completely randomized design (control, cadmium, 20 mg/L Fe3O4 nanoparticles,40 mg/L Fe3O4 nanoparticles, 20 mg/L Fe3O4 nanoparticles + cadmium, 40 mg/L Fe3O4 nanoparticles + cadmium) to study the mitigating role of Fe3O4 nanoparticles on cadmium stress in three Raphanus sativus cultivars namely i.e., MOL SANO, MOL HOL PARI, MOL DAQ WAL. The plant growth, physiological and biochemical parameters i.e.,shoot length, shoot fresh weight, shoot dry weight, root length, root fresh and dry weight, MDA content, soluble protein contents, APX, CAT, POD activities and ion concentrations, membrane permeability, chlorophyll a, chlorophyll b and anthocyanin content, respectively were studied. The results displayed that cadmium stress remarkably reduces all growth, physiological and biochemical parameters for allcultivars under investigation. However, Fe3O4 nanoparticles mitigated the adverse effect of cadmium by improving growth, biochemical and physiological attributes in all radish cultivars. While, 20 mg/L Fe3O4 nanoparticles have been proved to be more useful against cadmium stress. The outcome of present investigation displayed that Fe3O4 nanoparticles can be utilized for mitigating heavy metal stress.

Unveiling the efficacy of Bacillus faecalis and composted biochar in alleviating arsenic toxicity in maize

Arsenic (As) contamination is a major environmental pollutant that adversely affects plant physiological processes and can hinder nutrients and water availability. Such conditions ultimately resulted in stunted growth, low yield, and poor plant health. Using rhizobacteria and composted biochar (ECB) can effectively overcome this problem. Rhizobacteria have the potential to enhance plant growth by promoting nutrient uptake, producing growth hormones, and suppressing diseases. Composted biochar can enhance plant growth by improving aeration, water retention, and nutrient cycling. Its porous structure supports beneficial microorganisms, increasing nutrient uptake and resilience to stressors, ultimately boosting yields while sequestering carbon. Therefore, the current study was conducted to investigate the combined effect of previously isolated Bacillus faecalis (B. faecalis) and ECB as amendments on maize cultivated under different As levels (0, 300, 600 mg As/kg soil). Four treatments (control, 0.5% composted biochar (0.5ECB), B. faecalis, and 0.5ECB + B. faecalis) were applied in four replications following a completely randomized design. Results showed that the 0.5ECB + B. faecalis treatment led to a significant rise in maize plant height (~ 99%), shoot length (~ 55%), root length (~ 82%), shoot fresh (~ 87%), and shoot dry weight (~ 96%), root fresh (~ 97%), and dry weight (~ 91%) over the control under 600As stress. There was a notable increase in maize chlorophyll a (~ 99%), chlorophyll b (~ 81%), total chlorophyll (~ 94%), and shoot N, P, and K concentration compared to control under As stress, also showing the potential of 0.5ECB + B. faecalis treatment. Consequently, the findings suggest that applying 0.5ECB + B. faecalis is a strategy for alleviating As stress in maize plants.

Dynamic physiological response of tef to contrasting water availabilities.

Global climate change is leading to increased frequency of extreme climatic events, higher temperatures and water scarcity. Tef (Eragrostis tef (Zucc.) Trotter) is an underutilized C4 cereal crop that harbors a rich gene pool for stress resilience and nutritional quality. Despite gaining increasing attention as an "opportunity" crop, physiological responses and adaptive mechanisms of tef to drought stress have not been sufficiently investigated. This study was aimed to characterize the dynamic physiological responses of tef to drought. Six selected tef genotypes were subjected to high-throughput whole-plant functional phenotyping to assess multiple physiological responses to contrasting water regimes. Drought stress led to a substantial reduction in total, shoot and root dry weights, by 59%, 62% and 44%, respectively (averaged across genotypes), and an increase of 50% in the root-to-shoot ratio, relative to control treatment. Drought treatment induced also significant reductions in stomatal conductance, transpiration, osmotic potential and water-use efficiency, increased chlorophyll content and delayed heading. Tef genotypes exhibited diverse water-use strategies under drought: water-conserving (isohydric) or non-conserving (anisohydric), or an intermediate strategy, as well as variation in drought-recovery rate. Genotype RTC-290b exhibited outstanding multifaceted drought-adaptive performance, including high water-use efficiency coupled with high productivity under drought and control treatments, high chlorophyll and transpiration under drought, and faster drought recovery rate. This study provides a first insight into the dynamic functional physiological responses of tef to water deficiency and the variation between genotypes in drought-adaptive strategies. These results may serve as a baseline for further studies and for the development of drought-resistant tef varieties.

Wheat growth, yield, nutrient concentration and soil chemical properties influenced by liming in an acid soil

Soil acidity has negative effects on both plants and soil. Furthermore, liming is the most common and effective management practice used to neutralize the acid produced in the soil and the problems associated with soil acidification. The study evaluated whether liming impacts wheat growth, yield, nutritional status basis exchangeable, and their related soil acidity indices. A greenhouse experiment was performed under a completely randomized arrangement, with four lime application rates equivalent to (0, 4.0, 8.0, and 12.0 Mg ha−1). The results showed that all yield components significantly increased with increasing lime addition rate. The grain yield, shoot and root dry weight, and plant and spike height improved quadratically (R 2 = 0.909, 0.950, 0.976, 0.902, and 0.891, respectively). Additionally, the lime rate influenced P and Mg concentrations in the shoot, and the concentrations of Cu and Zn. With increasing lime rate, the soil exchangeable Ca and Mg concentrations increased quadratically (R 2 = 0.969 and 0.984), while the soil exchangeable K and Al concentrations decreased significantly. The pH of the soil solution increased linearly (R 2 = 0.994) with the lime addition rate. Liming significantly reduced the exchangeable Al3+ and Al + H in the soil. Finally, liming improves wheat yield in acid soil by reducing the negative effects of Al and H by increasing soil pH, Ca2+, and Mg2+ concentration, consequently improving root growth and resulting in wheat yield. Liming increased the grain yield by 188.7, 198.2, and 322.8% following the increase of lime rate, if compared to the control. Furthermore, lime enhances plant resilience by raising pH and improving soil nutrient availability and the root system.

Synergistic application of Bradyrhizobium yuanmingense and Trichoderma species improves tolerance of cowpea to aluminum stress by enhancing the antioxidant defense system

The positive effects of Trichoderma on the antioxidant responses of nodulated cowpea plants under aluminum (Al) stress are not well documented. This study aims to evaluate the effects of different microbial consortia of Bradyrhizobium yuanmingense (bradyrhizobia) and Trichoderma species (T. asperelloides T02, T. asperellum T77, or T. harzianum T78) on the growth and antioxidant responses of cowpea under Al stress. Coinoculation with Bradyrhizobia and Trichoderma resulted in greater growth (plant height and root length) and biomass (dry weight of shoots and roots) compared to single inoculations. The dual application of bradyrhizobia and T. asperellum T77 to Al-treated plants increased chlorophyll-a (36 %), chlorophyll-b (210 %), and carotenoid (92 %) contents. Under Al stress, plants inoculated with bradyrhizobia exhibited a 53 % increase in anthocyanin content compared to the unstressed control. The highest levels of reduced ascorbate and ascorbate redox state were observed in plants coinoculated with bradyrhizobia and Trichoderma, whereas oxidized ascorbate accumulated more in plants with single inoculations (bradyrhizobia or Trichoderma). Lipid peroxidation and hydrogen peroxide levels were 50 % lower in plants coinoculated with bradyrhizobia and Trichoderma. Additionally, these plants showed increased activities of superoxide dismutase, catalase, ascorbate peroxidase, and peroxidases under Al stress, particularly in those coinoculated with bradyrhizobia and T. asperelloides T02 and T. harzianum T78. Our results confirm that the presence of bradyrhizobia and Trichoderma in the cowpea rhizosphere mitigates oxidative damage caused by reactive oxygen species under Al stress and positively influences cowpea growth and development under stressful conditions.

Efek Konsentrasi Eko-Enzim dan Pupuk NPK Terhadap Pertumbuhan Bibit Kopi Liberika (Coffea Liberica W Bull Ex Hiern) Tungkal Jambi

This study aims to investigate the influence of various concentrations of Eco-Enzyme and NPK fertilizer on the growth of Liberika Tungkal Jambi coffee seedlings and to determine the optimal concentrations of Eco-Enzyme and NPK fertilizer for the growth of Liberika Tungkal Jambi coffee seedlings. The study utilized a Randomized Block Design (RAK) consisting of 6 treatment levels, as follows: P0 = No Eco-Enzyme (100% Inorganic Fertilizer), P1 = Eco-Enzyme Concentration 50 mL. + 50% Inorganic Fertilizer, P2 = Eco-Enzyme Concentration 100 + 50% Inorganic Fertilizer, P3 = Eco-Enzyme Concentration 150 mL. + 50% Inorganic Fertilizer, P4 = Eco-Enzyme Concentration 200 mL. + 50% Inorganic Fertilizer, and P5 = Eco-Enzyme Concentration 250 mL.+ 50% Inorganic Fertilizer. The observed variables included plant height, number of leaves, stem diameter, total leaf area, shoot dry weight, root dry weight, and root shoot ratio.The research findings indicate that the application of Eco-Enzyme and NPK fertilizer had an impact on the growth of 6-month-old Liberika Tungkal Jambi coffee seedlings, particularly in terms of the number of leaves and total leaf area. The concentration of Eco-Enzyme at 50 mL.+ 50% Inorganic Fertilizer yielded the best growth results for the coffee plants.

Interactive effects of mycorrhizal, Azospirillum and nitrogen+phosphorus with limited irrigation on yield and morpho-physiological traits of evening primrose (Oenothera biennis L.) in arid and semi-arid regions

Evening primrose (Oenothera biennis L.) is a valuable medicinal plant known for its oil, which is rich in gamma-linolenic acid. However, the productivity and quality of evening primrose can be significantly affected by drought stress, a common challenge in arid and semi-arid regions. Water deficit stress not only limits plant growth and development but also affects physiological and biochemical processes. To mitigate the adverse effects of drought, the use of chemical and biological fertilizers has been explored. Mycorrhizal fungi and Azospirillum are known for their ability to enhance plant resilience to abiotic stresses, including drought, by improving nutrient uptake and promoting plant growth. Nitrogen and phosphorus (N+P) are essential nutrients that play crucial roles in plant metabolism and stress tolerance. This study aimed to assess the impact of mycorrhizal fungi, Azospirillum, and N+P on evening primrose under drought conditions. One experiment was conducted in two locations, Tehran (semi-arid) and Varamin (arid) in 2014 and 2015, using a greenhouse for growing plants and through field transplantation. Using a split factorial design within a randomized complete block layout, three irrigation regimes (50 %, 40 %, and 30 % of field capacity) constituted the main plots, while the subplots included three chemical fertilizer treatments (none, 50 %, and 100 % of N+P) and four biological fertilizer treatments (non-inoculated and inoculated with mycorrhizal fungi and Azospirillum) in factorial combinations. The study revealed that drought, both moderate and severe, resulted in reduced plant height, shoot dry weight, leaf area index, seed yield, harvest index, phosphorus content, relative water content, and oil yield. Notably, the highest water use efficiency occurred under moderate water deficit stress. Severe water deficit stress, however, led to the highest root dry weight, root ratio to shoot dry weight, and catalase activity. The application of chemical and biological fertilizers alleviated the negative effects of water deficit stress on plant growth and yield. Evening primrose water use efficiency increased under moderate water deficit stress, particularly when coupled with the application of chemical (N+P) and biological (mycorrhizal fungi and Azospirillum) fertilizers. The study emphasized the positive impact of mycorrhizal and Azospirillum inoculation on enhancing evening primrose growth under water deficit stress.

Biostimulant and Arbuscular Mycorrhizae Application on Four Major Biomass Crops as the Base of Phytomanagement Strategies in Metal-Contaminated Soils.

Using contaminated land to grow lignocellulosic crops can deliver biomass and, in the long term, improve soil quality. Biostimulants and microorganisms are nowadays an innovative approach to define appropriate phytomanagement strategies to promote plant growth and metal uptake. This study evaluated biostimulants and mycorrhizae application on biomass production and phytoextraction potential of four lignocellulosic crops grown under two metal-contaminated soils. Two greenhouse pot trials were setup to evaluate two annual species (sorghum, hemp) in Italy and two perennial ones (miscanthus, switchgrass) in China, under mycorrhizae (M), root (B2) and foliar (B1) biostimulants treatments, based on humic substances and protein hydrolysates, respectively, applied both alone and in combination (MB1, MB2). MB2 increased the shoot dry weight (DW) yield in hemp (1.9 times more), sorghum (3.6 times more) and miscanthus (tripled) with additional positive effects on sorghum and miscanthus Zn and Cd accumulation, respectively, but no effects on hemp metal accumulation. No treatment promoted switchgrass shoot DW, but M enhanced Cd and Cr shoot concentrations (+84%, 1.6 times more, respectively) and the phytoextraction efficiency. Root biostimulants and mycorrhizae were demonstrated to be more efficient inputs than foliar biostimulants to enhance plant development and productivity in order to design effective phytomanagement strategies in metal-contaminated soil.

Interactive effects of ammonium sulfate and lead on alfalfa in rare earth tailings: Physiological responses and toxicity thresholds

Ion-adsorption rare earth ore contains significant levels of leaching agents and heavy metals, leading to substantial co-contamination. This presents significant challenges for ecological rehabilitation, yet there is limited understanding of the toxicity thresholds associated with the co-contamination of ammonium sulfate (AS) and lead (Pb) on pioneer plants. Here, we investigated the toxicity thresholds of various aspects of alfalfa, including growth, ultrastructural changes, metabolism, antioxidant system response, and Pb accumulation. The results indicated that the co-contamination of AS-Pb decreased the dry weight of shoot and root by 26 %–77 % and 18 %–92 %, respectively, leading to irregular root cell morphology and nucleus disintegration. The high concentration and combined exposures to AS and Pb induced oxidative stress on alfalfa, which stimulated the defense of the antioxidative system and resulted in an increase in proline levels and a decrease in soluble sugars. Structural equation modeling analysis and integrated biomarker response elucidated that the soluble sugars, proline, and POD were the key physiological indicators of alfalfa under stresses and indicated that co-exposure induced more severe oxidative stress in alfalfa. The toxicity thresholds under single exposure were 496 (EC5), 566 (EC10), 719 (EC25), 940 (EC50) mg kg−1 for AS and 505 (EC5), 539 (EC10), 605 (EC25), 678 (EC50) mg kg−1 for Pb. This study showed that AS-Pb pollution notably influenced plant growth performance and had negative impacts on the growth processes, metabolite levels, and the antioxidant system in plants. Our findings contribute to a theoretical foundation and research necessity for evaluating ecological risks in mining areas and assessing the suitability of ecological restoration strategies.

Efficacy evaluation of biochar and activated carbon as carriers of bacterial inoculants in the remediation of multi-metal polluted soil

ABSTRACT Application of appropriate organic amendments as the carriers of bacterial consortium may improve the remediation efficiency of HMs-polluted soil. A greenhouse experiment was designed and carried out to investigate the capability of biochar, and activated carbon prepared from ostrich manure and almond husk as the carriers of bacterial inoculants in the phytoremediation of a calcareous soil polluted with Pb, Ni, Cd and Zn by maize. Results showed that the application of biochar and activated carbon prepared from ostrich manure increased root (78–129%) and shoot (72.3–272%) dry weight, as compared to the control. The values of metal accumulation in both maize root and shoot were in the order of Cd>Zn>Ni>Pb. While biochar and activated carbon prepared from ostrich manure significantly increased both root and shoot metals uptake, those prepared from almond husk drastically decreased the uptake of some metals. The foremost mechanism involved in the phytoremediation of Cd, Ni and Pb was phytostabilization while that of Zn was due to the phytoextraction. Results of the present study demonstrated the effectiveness of ostrich manure-derived biochar and activated carbon as an efficient treatment in the phytoremediation of multi-metal-polluted soils and the mitigation of HMs phytotoxicity.

Standardization of Propagation Techniques in Annual Moringa (Moringa oleifera Lam.) for Enhancing Crop Uniformity

An investigation on annual Moringa, Moringa oleifera Lam., var., (PKM 1 and PKM2) with the objective of standardizing the method of vegetative propagation was carried out at Horticultural College and Research Institute, Periyakulam. the treatment consisted of three factors viz., cultivars (Factor 1: Moringa variety PKM 1 and PKM2), propagation methods (Factor 2: hardwood cuttings, semi hardwood cuttings and air layering) and application of different concentration of growth regulator IBA (Factor 3:0, 1500, 2500 and 4000 ppm) and the trial was laid out with twenty four treatments using Factorial Randomized Block Design with three replications. The overall result revealed that the treatment combinations of PKM 1 air layering treated with IBA 4000 ppm registered the highest dry matter content of root (70.00%) and PKM 1 hardwood cuttings treated with IBA 4000 ppm recorded the highest dry shoot to root ratio (9.19). In PKM 2 semi hardwood cuttings treated with IBA 1500 ppm registered the highest root length (16.30cm) and dry matter content of shoot (61.99%). PKM 2 air layers treated with IBA 4000 ppm took minimum number of days to root (17.99 days), days to sprout (9.85 days) had the highest root fresh weight (2.70g), root dry weight (1.80g), shoot fresh weight (12.52g) and shoot dry weight (6.90g). This study concluded that air layering with 2500 to 4000 ppm IBA treatment is best pro pragation method for PKM1 and PKM 2 annual moringa.

Mesorhizobia strain and chickpea variety drive phenotypic plasticity of plant growth and nodulation

Chickpea (Cicer arietinum) establishes symbiotic relationships with several Mesorhizobium species and the three-way interaction between chickpea variety, Mesorhizobium strain, and environment, drives plant growth and nitrogen fixation. Here we quantified the phenotypic plasticity for shoot dry weight, nodule dry weight, nodules per plant, nodule colour, symbiotic effectiveness, and nitrogen cost in a factorial experiment combining five chickpea varieties, seven Mesorhizobium strains and three photothermal regimes. Plant growth and nitrogen fixation traits varied with variety, Mesorhizobium strain, photothermal environment and their interaction. Phenotypic plasticity was larger for nodules per plant (7.3-fold) than for shoot dry weight (2.7-fold), verifying a hierarchy of plasticities between these traits. Strain-driven plasticity of plant growth and nitrogen fixation traits was larger than variety-driven plasticity for our combination of varieties, strains, and photothermal environments, with strain-driven phenotypic plasticity being 2.7-fold vs 1.4-fold for shoot dry matter, 2.5-fold vs 1.7-fold for nodule dry weight, 7.3-fold vs 2.1-fold for nodules per plant, 3.7-fold vs 1.7-fold for nodule color, 2.9-fold vs 1.6-fold for symbiotic effectiveness, and 2.3-fold vs 1.6-fold for nitrogen cost. Our study provides insights on the phenotypic plasticity of the legume-rhizobia interaction by considering the plants as part of the rhizobia environment and vice-versa.

Germination test, seedling growth, and physiochemical traits are used to screen okra varieties for salt tolerance

Excess soil salinity is a major stress factor that inhibits plant growth, development, and production. Among the growth stages, seed germination is particularly susceptible to salt stress. Okra, a nutraceutical vegetable, has a low germination percentage. Literature has revealed genetic diversity in okra, which can be studied to develop salt-tolerant varieties. This study examined the salt tolerance of 13 okra varieties using germination tests and then tested five varieties in pot experiments with different NaCl levels (75, 100, and 125 mM NaCl). Results showed that salt levels affected all varieties, with differential variations in stress response. Salt stress reduced agronomic, and physiochemical traits in the studied varieties. In variety “MALAV-27”, the highest salt concentration significantly reduced the shoot length (68.12 %), root length (65.11 %), shoot fresh weight (78.73 %), root fresh weight (68.32 %), shoot dry weight (75.60 %), and root dry weight (75.81 %), along with different physiochemical traits. Variety “NAYAB-F1” performed the best, and maintained the highest shoot length (57.12 %), root length (58.72 %), shoot fresh weight (68.26 %), and root fresh weight (58.34 %), shoot dry weight (69.23 %), root dry weight (62.50 %), and numerous physiochemical traits such as sugar (0.74 μg/g), proline (0.51 μmol/g), and chlorophyll ‘a’ (7.97 mg/g), chlorophyll ‘b’ (9.56 mg/g). The study recommended ‘NAYAB-F1′, ‘Arka anamika’, and ‘Shehzadi’ as salt-tolerant varieties suitable for selection in salt-tolerant okra breeding programs.

Zinc phytotoxicity and cationic micronutrients contents in quinoa as influenced by high Zn levels and soil amendments

Contamination of soils with heavy metals (HMs) is a serious concern due to the non-biodegradability and accumulation of these metals in living organism. The aim of this study was to evaluate the effectiveness of fish scale powder, chitin, and chitosan in reducing zinc (Zn) accumulation of quinoa grown on Zn-polluted soil. A 3*4 factorial greenhouse trial was conducted with three levels of Zn contamination (0, 100, and 200 mg kg−1) and four types of amendment (control, and 0.15% of each fish scale powder, chitin, and chitosan). The quinoa seeds were sown in soil treated with Zn contamination and amendments. Results showed that application of amendments especially chitosan increased shoot and root dry weight and greenness index of quinoa leaf. While high soil Zn levels decreased cationic micronutrients uptake in quinoa shoot, chitosan addition desirably enhanced cationic micronutrients uptake in quinoa shoot. Overall, amendment addition significantly decreased Zn concentration and uptake in plant; the highest decrease was observed following the application of chitosan. Although the application of high Zn levels significantly increased the values of phytoextraction efficiency, application of chitin and chitosan significantly decreased it. The value of translocation factor was lower than one, demonstrating that a large amount of Zn was stabilized in the root tissues, while a small amount of this metal was transferred to aboveground parts of quinoa. Results of this study revealed that fish scales derivatives were effective in preventing Zn toxicity and at the same time increasing cationic micronutrients contents of quinoa grown on HMs-polluted soil.

Morfologi Bawang Merah (Allium ascalonicum L.) Pada Cekaman Kekeringan Terhadap Aplikasi Asam Salisilat

Shallots are the vegetable crop with the highest production in Indonesia. However, the problem with cultivating shallots is that they are not resistant to environmental stress such as drought. The decrease in soil water content to 60% of available water has caused a drought stress effect on shallot plants. The strategy that can be used to limit the harmful effects of lack of water on shallots is the application of salicylic acid. Salicylic acid plays an important role that enhances plant growth and development under drought stress conditions by reducing cell membrane damage in water-stressed plant leaves by reducing cellular lipid peroxidation and H2O2 accumulation. This research aimed to study the growth, yield and physiological responses of shallots under drought stress conditions with the application of salicylic acid. This research was carried out in the greenhouse of the Faculty of Agriculture, University of North Sumatra, Medan from April to June 2024. This research used a factorial randomized block design with 2 treatment factors. The first factor of antioxidant spraying consisted of 4 levels, namely 0 mM (control), 0.5 mM, 1 mM and 1.5 mM. The second factor was the level of drought stress (percentage of soil water content) which consisted of 3 levels, namely 80%, 60% and 40% FC. The results showed that drought stress decreased plant height, number of leaves, number of tillers, shoot fresh weight, root fresh weight, shoot dry weight, root dry weight. Meanwhile, application of salicylic acid up to 1 mM could increas shoot fresh weight, root fresh weight, shoot dry weight, and root dry weight.