Higher Root Research Articles

Optimizing callus induction and indirect organogenesis in non-dormant corm explants of Gloriosa superba (L.) via media priming

IntroductionGloriosa superba L. is an endangered ornamental plant of significant medicinal, commercial, and cultural value. This study establishes an efficient protocol for rapid in vitro propagation of this plant species through callus-mediated organogenesis using non-dormant corm explants.MethodsPlant tissue culture techniques were employed to facilitate the in vitro regeneration process of Gloriosa superba L. This encompassed various stages, including the acquisition of plant material, surface sterilization, formulation of growth media, and the execution of callogenesis, shooting, rooting, and acclimatization experiments.Results and DiscussionInvestigation into the impact of plant growth regulators on callogenesis unveiled diverse callus morphologies, dependent on regulator type and concentration, with the NAA and KN combination emerging as the most effective for callus induction. Specifically, the callus induction medium supplemented with 1.5 mg L−1 NAA, 0.5 mg L−1 KN, and 10 mg L−1 casein hydrolysate (CH) achieved remarkable results, boasting an 81.25% callus induction rate and a substantial callus biomass fresh weight of 333 mg. Furthermore, the combination of BAP and NAA facilitated optimal shoot primordia induction and shooting in callus derived from non-dormant corm explants. The shoot induction medium, enriched with 2.0 mg L−1 BAP, 0.5 mg L−1 NAA, 5 mg L−1 CH, and 20% (v/v) coconut water (CW), resulted in an impressive 83.33% shoot primordia formation rate and an average of 6.86 shoot primordia per callus. For root induction, the medium supplemented with 1.0 mg L−1 IBA displayed a high root induction rate of 81.25% and robust rooting (+++). Successful acclimatization of in vitro plantlets in controlled environments and shade net houses culminated in thriving growth, and upon transplantation into a garden soil blend (garden soil : sand : vermiculite, 2:1:1, v/v), with direct sunlight exposure, the plantlets demonstrated commendable development and form, boasting a 69% survival rate at the seven-week mark. These findings offer a robust foundation for scalable and sustainable propagation strategies, ensuring the conservation and utilization of this valuable species.

Alternative products for controlling Sclerotinia sclerotiorum in vivo AND in vitro in canola crops

Products that activate plant defense mechanisms, such as white mold, may increase the disease control spectrum in canola crops as an alternative to chemical control for disease management, aiming at lower environmental impacts and selection pressure on pathogens. This study evaluated Sclerotinia sclerotiorum control and resistance induction in canola crops with alternative products. In vitro and detached leaf experiments were conducted in a laboratory, and in vivo experiments occurred in a greenhouse. High Roots®; V6®; Maxi Flor®; Wert Plus®; potassium, manganese, and copper phosphites; manganese; procymidone fungicide; and Ascophyllum nodosum, Bacillus subtilis, and Bacillus thuringiensis extracts assessed S. sclerotiorum mycelial growth in vitro in detached leaves, white mold severity in a greenhouse, and enzymatic analysis in leaf tissues. The last two experiments also received the acibenzolar-S-methyl and Trichoderma asperellum treatments. S. sclerotiorum mycelial growth showed 100% inhibition under B. subtilis and Wert Plus® at 1000 ppm and procymidone at 100 and 1000 ppm in vitro. The procymidone and B. subtilis treatments in detached leaves inhibited 100% of fungus growth. The greenhouse experiments with lower severity were procymidone, copper phosphite, B. thuringiensis, B. subtilis, manganese phosphite, potassium phosphite, High Roots®, and V6®. Higher peroxidase enzyme activity occurred in plants treated with acibenzolar-S-methyl, copper phosphite, and fungicide 48 hours after pathogen inoculation. The polyphenol oxidase enzyme did not show activity. Alternative products were responsive and may aid the chemical control of white mold in canola crops.

Nitrogen and phosphorus availability alters tree‐grass competition intensity in savannas

Abstract Plant essential macronutrients like nitrogen (N) and phosphorus (P) can limit savanna tree growth and are important determinants of savanna vegetation dynamics, along with rainfall, fire and herbivory. How nitrogen and phosphorus shape tree‐grass competition and their coexistence remain unclear, hindering our ability to predict how savannas may respond to altered nutrient cycling. Here, we evaluate (1) if trees and grasses respond differently to N versus P availability, or (2) if grasses are more competitive in low nutrient environments while trees are more competitive in high nutrient environments. To do this, we grew saplings of 6 tree and 1 grass species from the Kruger National Park, South Africa, for 16 weeks under fully factorial nutrient and competition treatments (with/without competitors, low/high rate of N supply and low/high rate of P supply) under a watering regime designed to mimic wet season rainfall in a mesic savanna. Trees and grasses foraged most aggressively for nitrogen and allocated biomass differently depending on nitrogen availability. Overall, tree growth decreased in competition with grass, even in high nutrient environments where they grew faster. Grasses were always better below‐ground competitors, utilising aggressive nutrient foraging strategies, including high root phosphatase activity in response to nitrogen and large root biomass allocation. Synthesis. In low nutrient environments (e.g. on nutrient‐poor sandy soils), nutrients may limit tree growth. Nutrient rich environments enable tree growth, but grasses continue to compete effectively with trees. Understanding what this means for ecosystem responses to nutrient availability is not trivial, especially in the context of fire and herbivory. However, it is clear that soil nutrients likely affect tree and grass growth and competition in savannas, which suggests that future changes in nutrient cycling, such as N deposition, may have important effects on savanna vegetation.

Effects of Long-Term High Temperatures in the Root Zone on the Physiological Characteristics of Grapevine Leaves and Roots: Implications for Viticulture Practices

Ridging cultivation and root restriction cultivation are beneficial due to their improvement of the soil permeability in the root zone of grapevine, and they are widely used in southern China, Japan, and other countries. However, with the intensification of global warming, when using ridging or root restriction cultivation, the soil temperature in the root zone can often reach 30 °C or even more than 35 °C during the summer, which is not conducive to the growth of grapevines. The aim of this study was to explore the effects of high root zone temperatures on the photosynthetic fluorescence characteristics of grapevine leaves, root respiration, and degree of lignification of roots and shoots, as well as to provide a theoretical foundation for the management of grapevine production and cultivation. One-year-old potted ‘Kyoho’ was used as the study material. Three root temperature treatments were implemented for 15 days (9:00–16:00): 25 °C (CK), 30 °C (T1), and 35 °C (T2). The results showed that the malondialdehyde and H2O2 levels in leaves increased, while the chlorophyll content decreased. The oxygen-evolving complex was inactivated, and PSII donor and acceptor sides were blocked, thus reducing the photosynthetic gas exchange capacity at high root zone temperatures. The grapevine root activity and root/shoot ratio decreased. Simultaneously, the lignin content in the roots and shoots increased. In addition, there was a significant increase in the expression of key genes (PAL, C4H, 4CL, F5H, COMT, CCR, and CAD) in the root lignin synthesis pathway. Heightened root zone temperatures increased cyanide-resistant respiration in roots and heat release in the PPP pathway to alleviate stress damage. Therefore, it is recommended to use grass, mulching, and other cultivation management methods to maintain root zone temperatures below 30 °C in order to ensure the normal growth of grapevines and promote a high and stable yield.

Quantitative structure-activity relationship model development for estimating the predicted No-effect concentration of petroleum hydrocarbon and derivatives in the ecological risk assessment

Quantitative structure-activity relationship (QSAR) is a cost-effective solution to directly and accurately estimating the environmental safety thresholds (ESTs) of pollutants in the ecological risk assessment due to the lack of toxicity data. In this study, QSAR models were developed for estimating the Predicted No-Effect Concentrations (PNECs) of petroleum hydrocarbons and their derivatives (PHDs) under dietary exposure, based on the quantified molecular descriptors and the obtained PNECs of 51 PHDs with given acute or chronic toxicity concentrations. Three high-reliable QSAR models were respectively developed for PHDs, aromatic hydrocarbons and their derivatives (AHDs), and alkanes, alkenes and their derivatives (ALKDs), with excellent fitting performance evidenced by high correlation coefficient (0.89–0.95) and low root mean square error (0.13–0.2 mg/kg), and high stability and predictive performance reflected by high internal and external verification coefficient (Q2LOO, 0.66–0.89; Q2F1, 0.62–0.78; Q2F2, 0.60–0.73). The investigated quantitative relationships between molecular structure and PNECs indicated that 18 autocorrelation descriptors, 3 information index descriptors, 4 barysz matrix descriptors, 6 burden modified eigenvalues descriptors, and 1 BCUT descriptor were important molecular descriptors affecting the PNECs of PHDs. The obtained results supported that PNECs of PHDs can be accurately estimated by the influencing molecular descriptors and the quantitative relationship from the developed QSAR models, that provided a new feasible solution for ESTs derivation in the ecological risk assessment.

Effects of Bio-inoculation on the Growth of Cabbage as Well as the Disease Progression of Alternaria Leaf Spot

Cabbage is one of the common Cole crop which is widely grown throughout India. It is affected various disease including, Alternaria leaf spot, black rot, club root, downy mildew and powdery mildew. Alternaria leaf spot, caused by Alternaria species such as A. brassicae and A. brassicicola, has been documented on every continent and is a prevalent disease affecting cabbage. Among the various diseases impacting cabbage, it stands out as a major contributor to yield loss, averaging between 32-57%. An experiment Effects of bio-inoculation on the growth of cabbage seedlings, as well as the disease progression of Alternaria leaf spot under challenge inoculation was conducted at Department of Plant Pathology, Rama University, Kanpur during 2023. Result of the study revealed that. application of Trichoderma as a seed treatment led to higher root and shoot dry biomass (0.080 and 0.021 mg/ seedling respectively), higher % increase in root and shoot dry weight (61.25and 82.78%) was found in T1 (Seed treatment with trichoderma harzianum) whereas highest root: shoot ratio (0.222) was reported in treatment T2.

Phytoremediation of copper-contaminated soils by rapeseed (Brassica napus L.) and underlying molecular mechanisms for copper absorption and sequestration

High levels of copper released in the soil, mainly from anthropogenic activity, can be hazardous to plants, animals, and humans. The present research aimed to estimate the suitability and effectiveness of rapeseed (Brassica napus L.) as a possible soil remediation option and to uncover underlying adaptive mechanisms A pot experiment was conducted to explore the effect of copper stress on agronomic and yield traits for 32 rapeseed genotypes. The copper-tolerant genotype H2009 and copper-sensitive genotype ZYZ16 were selected for further physiological, metabolomic, and transcriptomic analyses. The results exhibited a significant genotypic variation in copper stress tolerance in rapeseed. Specifically, the ratio of seed yield under copper stress to control ranged from 0.29 to 0.74. Furthermore, the proline content and antioxidant enzymatic activities in the roots were greater than those in the shoots. The accumulated copper in the roots accounted for about 50% of the total amount absorbed by plants; thus, the genotypes possessing high root volumes can be used for rhizofiltration to uptake and sequester copper. Additionally, the pectin and hemicellulose contents were significantly increased by 15.6% and 162%, respectively, under copper stress for the copper-tolerant genotype, allowing for greater sequestration of copper ions in the cell wall and lower oxidative stress. Comparative analysis of transcriptomes and metabolomes revealed that excessive copper enhanced the up-regulation of functional genes or metabolites related to cell wall binding, copper transportation, and chelation in the copper-tolerant genotype. Our results suggest that copper-tolerant rapeseed can thrive in heavily copper-polluted soils with a 5.85% remediation efficiency as well as produce seed and vegetable oil without exceeding food quality standards for the industry. This multi-omics comparison study provides insights into breeding copper-tolerant genotypes that can be used for the phytoremediation of heavy metal-polluted soils.

Sweet potato yield and quality characteristics affected by different late-season irrigation levels.

Seasonal late-season water deficits negatively affect the yield and quality of sweet potatoes in northern China. However, the amount of late-season irrigation to achieve high yield and consistent quality storage root remains undetermined. We assessed the yield and some qualitative traits of sweet potatoes such as size, shape, skin/flesh colour and nutritional content, as influenced by five irrigation levels (T0: unirrigated control; T1: 33% ETc; T2: 75% ETc; T3: 100% ETc; and T4: 125% ETc). Late-season irrigation significantly increased yield and marketable yield. Yields for T2 and T3 were significantly higher than other treatments, whereas T2 had the highest Grade A rating in a 2-year test. The vertical length of storage roots gradually increased with an increase in irrigation level, whereas the maximum width remained unchanged. The proportion of long elliptic and elliptic storage roots also increased, whereas the proportion of ovate, obovate and round storage roots gradually decreased. The skin and flesh colours became more vivid as the level of irrigation increased, with the skin colour becoming redder and the flesh colour becoming more orange-yellow. The levels of carotenoids, vitamin C and soluble sugar were significantly higher in irrigated crops, with the highest vitamin C and soluble sugar levels in T2 and the highest carotenoid levels in T3 treatment. Taken together, these results demonstrate the potential of moderate irrigation in the late-season to improve both yield production and quality potential. The results are of great importance for improving the market value of sweet potatoes and increasing grower profits. © 2024 Society of Chemical Industry.

Influence of medium and gelling agents concentration on in vitro rooting of Polygonum tinctorium

Polygonum tinctorium has long been employed in the medical and dye industries in many nations, particularly in Korea and Japan, for traditional fabric staining as a source of blue color. The plant tissue culture method has proven to be a rapid and sustainable approach for the regeneration of various plant species, particularly those with medicinal or ornamental value. In this study, we explored the in vitro root regeneration and growth of P. tinctorium in response to different growth media and gelling agents. Among the tested media, Schenk and Hildebrandt medium (SH medium) demonstrated superior performance, resulting in the highest number and length of roots per explant. SH media produced about 53 and 18% higher root per explant and a 40% and 14% increase in root length compared to B5 and MS media, respectively. Half strength of SH medium proved to be the optimal condition for both root number (7.46 roots per explant) and root length (3.81 mm). Among the gelling agents, 2 g/L of Gelrite medium was most effective in promoting the highest and tallest roots. These findings have the potential to enhance rooting abilities in various crops, particularly in the case of medicinal and ornamental plants, and may offer valuable insights for future industrial-scale root production of P. tinctorium.

Evaluation of Sweet Potato (Ipomoea batatas) for Early Blast Disease (Alternaria solani)

Aims: Early blight disease (Alternaria solani) is one of the main biotic factors limiting sweet potato production in the tropics. A multi-locational research was carried out to screen and identified sweet potato accessions that are resistant to the disease.
 Methodology: 21 sweet potato accessions were collected from different agro-ecological zones of Nigeria and screen against Alternaria solani by artificial inoculation of the pathogen in three diverse agro-ecological conditions. The accessions were named against their place of condition. The research were laid out in a Randomized Complete Block Design (RCBD) with three replications. Data were collected on days to 50% flowering, fresh root weight per plant, number of root per plant, number of main branches per plant, and above ground fresh biomass yield per plant at 15 weeks after planting (WAP). Disease scoring was done using rating scale 0f 0-9 and analyzed with IRRI STAR software.
 Results: The result revealed that there are variations in the 21 accessions studied. Offa performed best across the three environments followed by Umudike while Ado-Ekiti had the least performance in term of root yield. The screening shows that none of the 21 accessions is highly resistant. Four of the accessions were resistant, six accessions were moderately resistant, four accessions were susceptible, and three accessions were moderately susceptible while 4 accessions were highly susceptible to the pathogen.
 Conclusion: The findings concluded that the resistant accessions that gave high number roots could be used as a gene pool for Alternaria solani resistance breeding for cultivar improvement. The use of the identified resistant accessions with high root yield by farmers is encouraged pending the time commercial Alternaria solani resistant cultivars will be readily available and accessible.

Variation of morpho-agronomical characteristics and genetic diversity of imported asparagus cultivars in Vietnam

Asparagus (Asparagus officinalis L.) is a perennial plant globally known for its unique texture, good flavor, and high nutritional value. This paper aims to provide information on the phenotypic traits, the situation of stem blight disease of the imported asparagus varieties and introduce suitable asparagus cultivars for Vietnam. The evaluation of morpho-agronomical characteristics variability of 13 imported asparagus cultivars in the first growing year was arranged in a Random Complete Block Design (RCBD) with 3 replicates in Hanoi, Vietnam. Genetic diversity was assessed using hierarchical clustering on principal component analysis of all measured traits. The results showed that 13 asparagus cultivars were classified into 4 main groups matched with geographical origins based on principal component analysis. Atlas achieved the highest harvested yield (11.4 quintals ha-1) in the first harvesting time, which is correlated with high root CHOs level, followed by UC157, WB231 and Grande varieties. Purple passion had the highest sugar and vitamin C content. However, all varieties were infected with stem blight disease. In general, Atlas could be recommended for asparagus cultivation in Vietnam with high yield and good quality

Performance study of an energy harvester with multiple piezoelectric disks in parallel connection for water pressure pulsation

Water hydraulic pump is a crucial component of the water hydraulic system, and it generates periodic pressure pulsation due to its inherent characteristics. To harvest the vibration energy from the pressure pulsation, an energy harvester with multiple piezoelectric disks in parallel connection is proposed. Two prototypes are fabricated to analyze the effect of the number of piezoelectric disks on the energy harvesting characteristics under different pressures and resistances. Parameter matching is also carried out to obtain high root mean square (RMS) voltage and average power. For both prototypes, the cyclical change of deformation is caused by the pressure pulsation, leading to transient variation of voltage. Moderate thickness of piezoelectric ceramic and small thickness of copper substrate are advantageous for generating higher electrical energy output. Pressure pulsation significantly affects the harvested voltage and power, with the main influencing factor being the pulsation amplitude rather than static pressure. Additionally, transient voltage and RMS voltage increase with increasing resistance, while average power first rises and then falls. Comparing the two prototypes, both voltage and optimal resistance decrease when the number of piezoelectric disks in parallel connection increases. The average power and power density with two piezoelectric disks can reach 447 μW and 4.56 mW cm−3 under 3 MPa and at a resistance of 20 KΩ. This research provides guidance for the design, optimization and application of piezoelectric energy harvesters in water hydraulic system.

PHYSIOLOGICAL AND ANATOMICAL RESPONSES OF COMMON BEAN (PHASEOLUS VULGARIS L.) TO NICKLE NANOPARTICLES FOLIAR SPRAY

Nickel is an essential nutrient for plant growth with low concentrations, its excessive amounts in soil above threshold values could be cause in toxicity. The main objectives of the present research were to determine the effects of nickel nanoparticles foliar spray with 20, 40 and 70 nm diameter on the physiological characters and anatomical aspects of Phaseolus vulgaris L. plants. Lowest reduction significantly (P < 0.01) in root and shoot biomass was recorded due to in 70 nm; the measurements 0.08 and 0.05 g per plant and highest root: shoot; 0.65 as compared with control treatment. As well as the lowest conserved water content; 40% was observed in size 70 nm. While in size 40 nm Nickle nanoparticles increased chlorophyll a, b, total and carotenoids pigment contents. When the nickel nanoparticles size increased, the shoot and root tissue Ni concentrations also increased. However, the rate of Ni in root was greater than that observed in the shoot. While the Mn, Fe, Cu and Zn levels decreased due to applying nickel nanoparticles. The size of nanoparticles effects on the anatomical characteristics or structures such as stem, and leaf, also effects on the size of stomata.

Green manure provides growth benefits for soil mesofauna by promoting soil fertility in agroecosystems

The cultivation of leguminous green manure (LGM) crops in place of bare fallow in summer enhances soil fertility, which can positively impact soil life in the agroecosystem. An improvement in soil life, in turn, can promote soil fertility and agricultural sustainability. Based on an ongoing field trial in the Loess Plateau, China, we investigated the long-term effects of LGM crops and nitrogen (N) fertilization on soil mesofaunal community and analyzed the interrelationships among the various mesofaunal groups and soil fertility under dryland conditions. The results showed that the long-term growth of the LGM crops significantly increased the soil fertility and the abundance, richness, and diversity of the soil mesofaunal community compared to the fallow system. A total of 14 mesofaunal groups were identified only in the LGM system, mainly due to the high root biomass of the LGM crops. Among the three tested LGM crops, soybean and Huai bean performed better than mung bean in providing growth benefits and stable abiotic environments for the soil mesofaunal community. In addition, the long-term application of N fertilizer had an overall negative effect on the soil mesofaunal community under dryland conditions. Moreover, the abundance, richness, and diversity of the soil mesofaunal community were strongly correlated with soil fertility indicators. Hence, the analysis of the soil mesofaunal community can be used as a bioindicator of soil fertility in agroecosystems. The long-term growth of the LGM crops instead of bare fallow efficiently built a more sustainable and fertile soil in the agricultural ecosystem, thus providing a theoretical basis and guiding field management strategies for the development of sustainable agriculture in local and other similar dryland regions.

In Vitro Propagation of Commercially Used Krymsk 5® (Prunus fruticosa × Prunus lannesiana) Cherry Rootstock: Impact of Sugar Types and pH Levels

In the present study, the effects of different types of sugars and cultivation medium pH levels on the micropropagation of Krymsk 5® cherry rootstock were investigated. During the proliferation stage, the effects of four sugars (sucrose, fructose, glucose, and sorbitol) both separately and in two combinations were studied, along with the effects of pre-adjusted pH (4.5, 5.0, 5.2, 5.5, 5.8, 6.0, 6.2, or 6.5) on shoot proliferation parameters, growth medium’s post-autoclaving and post-cultivation pH, and their relations. Similarly, during the rooting stage, the effects of four sugars (sucrose, glucose, fructose, or sorbitol) at three concentrations (1% w/v, 2% w/v, or 3% w/v) without any auxin inclusion were studied as well as the effects of two sugars (sucrose or fructose) at six pre-adjusted pH levels (4.8, 5.2, 5.8, 6.2, or 6.5), also in the absence of auxin, on rooting parameters. Explants cultivated in fructose-supplemented growth mediums exhibited superior proliferation performance, characterized by the highest values of shoots per explant, shoot length, and nodes per explant. Generally, the medium’s pH decreased after autoclaving, and proliferation performance was favored by low pH values (either pre-adjusted or post-autoclaving). As far as rooting is concerned, fructose inclusion induced a higher rooting percentage (88%) compared to sucrose. The highest rooting was obtained in fructose-supplemented rooting mediums at concentrations of 2% or 3% w/v (95% rooting in both cases), in the absence of auxins. Post-autoclaving pH in fructose-supplemented rooting mediums was lower and buffered in low pH levels than in sucrose-supplemented ones, and the rooting of explants in all pH combinations with fructose exceeded 75%. In addition, rooting was negatively correlated with the post-autoclaving pH. These findings underscore the significance of both the sugar type and the post-autoclaving pH of the medium in both proliferation and rooting stages, highlighting their possible physiological, biochemical, or hormonal effects. Additionally, rooting without the use of auxin, but with the correct choice of sugar, emerges with both financial and environmental benefits, whereas fructose could be potentially used as a buffering agent.

Early generation clonal selection of sweetpotato (Ipomoea batatas (L.) Lam) using an accelerated breeding scheme

The breeding stages of a clonally propagated crop entails several steps and can take more than five years from hybridisation till cultivar release. The Accelerated Breeding Scheme (ABS) in sweetpotato relies on the use of multiple locations at the early breeding stages to reduce the years required for field evaluation. The aim of the study was to select the best progenies based on the ABS in sweetpotato towards the development of genotypes that combine high protein content with other important agronomic traits. Botanical seeds were generated from crosses between two diverse sets of parents, crossed using a North Carolina II design. F1-progenies (n = 363) were planted in a lattice design at three distinct locations during the 2017/18 planting season. Parameters recorded included pest and disease infestation, storage root traits and yield components, root protein content and nutrient related traits. Nutrient content was determined by near-infrared spectrometry. Analysis of variance and multiple t-distribution test and best test grouping were performed. There were significant differences (p < 0.001) among the genotypes for total number of roots, total root yield, marketable number of roots and marketable yield. The severity of Alternaria blight was significantly higher at Jozini. Forty progenies were selected (12.8% selection pressure) based on agronomic performance. Using the nutrient content results, four promising orange-fleshed clones (NC12-9, NC53-11, NC55-8, NC55-2) and one cream-fleshed clone (NC51-1) were identified with high storage root protein, iron and zinc contents. NC51-1 and NC55-2 produce promising storage root yields. The ABS approach is resource-demanding in the first phase but advances progenies rapidly to the subsequent breeding phases for cultivar release.

Transcriptome and biochemical analysis in hexaploid wheat with contrasting tolerance to iron deficiency pinpoints multi-layered molecular process

Iron (Fe) is an essential plant nutrient that is indispensable for many physiological activities. This study is an effort to identify the molecular and biochemical basis of wheat genotypes with contrasting tolerance towards Fe deficiency. Our physiological experiments performed at the early growth stage in cv. Kanchan (KAN) showed Fe deficiency tolerance, whereas cv. PBW343 (PBW) was susceptible. Under Fe deficient condition, KAN showed delayed chlorosis, high SPAD values, and low malondialdehyde content compared to PBW, indicative of Fe deficient condition. Comparative shoot transcriptomics revealed increased expression of photosynthetic pathway genes in PBW, further suggesting its sensitivity to Fe fluctuations. Under Fe deficiency, both the cultivars showed distinct molecular re-arrangements such as high expression of genes involved in Fe uptake (including membrane transporters) and its remobilization. Specifically, in KAN these changes lead to high root phytosiderophores (PS) biosynthesis and its release, resulting in enhanced Fe translocation index. Utilizing the non-transgenic TILLING (Targeting Induced Lesions in Genomes) technology, we identified TaZIFL4.2D as a putative PS efflux transporter. Characterization of the wheat TILLING lines indicated that TaZIFL4.2 functions in PS release and Fe acquisition, thereby imparting tolerance to Fe deficiency. Altogether, this work highlights the mechanistic insight into Fe deficiency tolerance of hexaploid wheat, thus enabling breeders to select suitable genotypes to utilize nutrients for maximum yields.

Uncovering the complex relationship between plant diversity, soil properties, and mycorrhizal inoculum potential in threatened Miombo woodlands

AbstractArbuscular mycorrhizal fungi (AMF) are key members of soil microbial communities and play a key role in regulating ecosystem processes. However, the mutual interdependence of plants and AMF in threatened Miombo woodlands has not yet been fully elucidated. In this study, we investigated the relationship between plant ecological indicators and soil mycorrhizal inoculum potential (MIP) in the Miombo forest fallow of Haut‐Katanga, Democratic Republic of Congo, and identified plant species that positively influence soil MIP. We conducted a floristic inventory on 32 plots and collected soil cores for physicochemical and AMF characterization. Trap cultures using Crotalaria juncea seedlings were performed to determine the soil MIP. We also tested the AMF colonization status of randomly collected living roots of mature woody and dominant herbaceous species to identify explanatory variables for MIP. Our results showed that MIP was twice as high in silty clay soils (63.13%) than in clay soils (30%). Furthermore, MIP increased accordingly with the relative abundance of a group of woody and herbaceous species (e.g., Albizia adianthifolia, Baphia bequaertii, and Setaria pumila) and decreased with others (e.g., Combretum collinum, Harungana madagascariensis and Hyparrhenia diplandra). Linear regressions showed that MIP increased significantly with the specific richness of woody species identified as indicators and with the amount of annual herbs. Woody legumes with high root colonization by AMF appeared to be refuge plants, and primary AMF dispersal vectors, increasing soil MIP. This study provides baseline data that can be used to formulate ecological restoration strategies, including soil and vegetation protection.

Enhancing food production in hot climates through radiative cooling mulch: A nexus approach

With a booming population, global food demand is increasing rapidly. Various methods have been proposed to alleviate heat stress and improve yields for agriculture in hot climates. However, the damage caused by high root temperatures cannot be avoided due to a lack of efficient regulation strategies. In this work, we investigate a new soil-cooling strategy based on the daytime radiative cooling film. This film has a high emissivity across the atmospheric window, along with a high reflectivity in the solar spectrum. With a soil temperature drop of 12.5°C, the germination rate of cherry radish is improved from 39.6% to 81.3% after using this mulch. In a field test during a hot summer, this mulch increased the fresh weight yield of Chinese cabbage by 127.4%, which was attributed to reduced root heat stress. Moreover, the applicability of this radiative cooling mulch in diverse geographical and climatic conditions was discussed based on a global-scale simulation. The limitations of this radiative cooling mulch and future development perspectives were discussed here. This passive cooling strategy paves a new way to tackle the water-food crisis without extra energy consumption.

Heavy Metal Co-Resistance with Antibiotics amongst Plant Growth Promoting Bacteria Isolates from Rhizosphere of Nypa Fruticans

Heavy metal co-resistance with antibiotics has the potential to amplify antimicrobial resistance genes in the environment, and this could have an impact on clinical settings. This study aimed to investigate the presence of heavy metal co-resistance with antibiotics among plant growth promoting bacterial isolates from the rhizosphere of Nypa fruticans. The heavy metals content of the water habouring the Nypa fruticans including copper(0.07mg/L), chromium (2.3 mg/L), lead (4.22 mg/L), iron (12.4 mg/L), cadmium (0.45 mg/L), nickel (3.12 mg/L), arsenic (0.47 mg/L) and zinc (5.37 mg/L) were above acceptable limits of WHO. A total of 10 bacteria including Bacillus subtilis, Bacillus cereus, Pseudomonas fluorescens, Klebsiella oxytoca, Serratia marcescens, Achromobacter denitrificans, Bulkholderia vietnamiensis and Azospirrilum brasilense, Azobacter vinelandii and Enterobacter aerogenes were isolated and identified to specie level using 16s RNA gene sequences, which showed above 95 % similarity with reference sequences from GenBank. The isolates showed high resistance to lead, chromium and zinc. Most of the isolates were resistant to streptomycin, ciprofloxacin and augmentin. Also, most of the isolates demonstrated positive growth promoting activities of indole acetic acid production, nitrogen fixation, siderophore production and phosphate solubilization. Pot trials on the effect of heavy metal and antibiotic tolerant bacteria on growth of beans (Phaseolus vulgaris l.) in heavy metal polluted soil revealed that beans treated with consortiumof all the isolates recorded high shoot and root length. Hence these isolates can be used for bioremediation of metal polluted site and as well act as plant growth promoting bacterial in agricultural system.