ABSTRACT
Allagoptera campestris is an acaulescent, rhizomatous palm tree that occurs in grassland and savanna areas (Cerrado). In the Santa Bárbara Ecological Station (Águas de Santa Bárbara, São Paulo, Brazil) the species is found growing in three distinct conditions: 1) in the understory of Pinus species plantations introduced in the 1970s in formerly open savanna, 2) in an area where Pinus species cultivated in the 1970s were later removed and the remaining material burned, and 3) in an open, undisturbed savanna area without the interference of pines. Anatomical studies carried out with A. campestris leaves collected in the same three areas indicated leaf plasticity in response to growth conditions. To verify whether there are differences in vessel element morphology in belowground organs, light, and scanning electron microscopy analyses were conducted on portions just below the crown, in the middle of the rhizome, and the median portions of three longer adventitious roots sampled from three plants in each area. The study reveals significant variations in vessel element characteristics of A. campestris, with roots consistently displaying longer and larger elements than rhizomes, and environmental conditions, especially in pine understory, influence vessel dimensions, and hydraulic conductivity in a negative manner.
Subject(s)
Microscopy, Electron, Scanning , Arecaceae/growth & development , Arecaceae/anatomy & histology , Arecaceae/physiology , Plant Leaves/anatomy & histology , Plant Leaves/growth & development , Brazil , Plant Roots/anatomy & histology , Plant Roots/growth & development , Plant Roots/physiologyABSTRACT
Hymenaea stigonocarpa Mart. ex Hayne has leaves with adaxial and abaxial epidermis covered by a very thick cuticle, in addition to anatomical structures involved in reducing the amount of herbicide absorbed by plants. Thus, we tested the hypothesis that H. stigonocarpa is potentially resistant to the herbicide glyphosate, exposing the plants to different doses (0, 96, 240, 480, and 960 g a.e ha-1). We carried out assessments of the symptoms, anatomy, growth and physiology of the plants and found that exposure to glyphosate negatively affected the height and number of leaves of the plants. Leaf fall resulted in a reduction in the photosynthetic capacity of plants, which responded by investing in stem diameter. Despite this, no visual symptoms of glyphosate toxicity were observed at the concentrations evaluated and histochemical tests did not detect signs of oxidative stress in the leaves, nor starch accumulation, indicating that carbohydrate translocation was not impaired. These results confirm our hypothesis of tolerance of H. stigonocarpa to glyphosate. Furthermore, plants exposed to the lowest doses of glyphosate (96 and 240 g ha-1) showed good growth, photosynthesis, transpiration and photochemical potential responses, indicating a hormetic effect in this application range.
Subject(s)
Glycine , Glyphosate , Herbicides , Photosynthesis , Glycine/analogs & derivatives , Glycine/toxicity , Photosynthesis/drug effects , Plant Leaves/drug effects , Plant Leaves/chemistry , Herbicide ResistanceABSTRACT
Green lettuce (Lactuca sativa L.) is a popular leafy vegetable grown and consumed worldwide for its crisp texture and nutritional value. This study investigates the impact of different inorganic fertilizers on the growth and productivity of green lettuce, with the aim of determining the most effective fertilizers for producing vibrant green lettuce. The research was carried out at the Jaya Wijaya Research Centre, Faculty of Agriculture, Slamet Riyadi University, employing a randomized design with a single factor: the type of inorganic fertilizer. The experimental treatments included Nutrimax, NPK 25.7.7, and a control group, each replicated four times. Lettuce plants treated with Nutrimax exhibited superior performance across various metrics, including plant height (32.63 cm), leaf color intensity (3.25), leaf count (13.5 leaves), fresh weight (94.75 grams), and dry weight (5.33 grams). Statistical analysis using Analysis of Variance, followed by the Least Significant Difference test at a significance level of 5%, revealed a significant influence of fertilizer treatment on the growth and yield of green lettuce plants. The type of fertilizer applied significantly affected the growth and yield of green lettuce cultivated using a floating hydroponic system. The number of leaves on the plant directly impacted the fresh weight of the leafy vegetables. These findings can serve as a valuable guide for optimizing green lettuce cultivation practices to achieve maximum yields.
Subject(s)
Fertilizers , Lactuca , Lactuca/growth & development , Plant Leaves/growth & development , Nitrogen/analysisABSTRACT
Nanotechnology is a fast-growing field with large number of applications. Therefore, the current study, was designed to prepare Zinc Oxide nanoparticles (ZnO NPs) from A. modesta leaves extract through a cost-effective method. The prepared NPs were characterized through UV-Vis Spectroscopy (UV-Vis), Dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), scanning electron microscope (SEM), and energy dispersive X-ray (EDX). The XRD and DLS analysis revealed the hexagonal nanocrystalline nature of ZnO NPs. The FTIR results displayed multiple fictional groups and UV results confirmed its optical properties. The average size of the NPs was 68.3 nm with a band gap of 2.71 eV. The SEM images divulge a clover leaf shape of ZnO NPs. The EDX spectrum revealed the presence of zinc and oxygen. The prepared NPs showed excellent biomedical application. The highest antileishmanial activity was 68%, anti-inflammatory activity was 78%, total antioxidant capacity (TAC) was 79.1%, antibacterial potential (ZOI) 22.1 mm, and highest growth inhibition of 85 ± 2.1% against A. rabiei. The adsorption efficiency of 85.3% within 120 min was obtained. Conclusively ZnO NPs have shown potential biomedical and environmental applications and ought to be the more investigated to enhance their practical use.
Subject(s)
Anti-Infective Agents , Phytochemicals , Zinc Oxide , Zinc Oxide/pharmacology , Zinc Oxide/chemistry , Phytochemicals/pharmacology , Phytochemicals/chemistry , Spectroscopy, Fourier Transform Infrared , Anti-Infective Agents/pharmacology , Plant Extracts/pharmacology , Plant Extracts/chemistry , X-Ray Diffraction , Metal Nanoparticles/chemistry , Microbial Sensitivity Tests , Microscopy, Electron, Scanning , Antioxidants/pharmacology , Antioxidants/chemistry , Plant Leaves/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Nanoparticles/chemistry , Green Chemistry Technology/methodsABSTRACT
The application of non-imaging hyperspectral sensors has significantly enhanced the study of leaf optical properties across different plant species. In this study, chlorophyll fluorescence (ChlF) and hyperspectral non-imaging sensors using ultraviolet-visible-near-infrared shortwave infrared (UV-VIS-NIR-SWIR) bands were used to evaluate leaf biophysical parameters. For analyses, principal component analysis (PCA) and partial least squares regression (PLSR) were used to predict eight structural and ultrastructural (biophysical) traits in green and purple Tradescantia leaves. The main results demonstrate that specific hyperspectral vegetation indices (HVIs) markedly improve the precision of partial least squares regression (PLSR) models, enabling reliable and nondestructive evaluations of plant biophysical attributes. PCA revealed unique spectral signatures, with the first principal component accounting for more than 90% of the variation in sensor data. High predictive accuracy was achieved for variables such as the thickness of the adaxial and abaxial hypodermis layers (R2 = 0.94) and total leaf thickness, although challenges remain in predicting parameters such as the thickness of the parenchyma and granum layers within the thylakoid membrane. The effectiveness of integrating ChlF and hyperspectral technologies, along with spectroradiometers and fluorescence sensors, in advancing plant physiological research and improving optical spectroscopy for environmental monitoring and assessment. These methods offer a good strategy for promoting sustainability in future agricultural practices across a broad range of plant species, supporting cell biology and material analyses.
Subject(s)
Chlorophyll , Plant Leaves , Principal Component Analysis , Tradescantia , Plant Leaves/chemistry , Chlorophyll/analysis , Least-Squares Analysis , Fluorescence , Spectrometry, Fluorescence/methodsABSTRACT
In this research, we aimed to determine the antioxidant activity of an atomized extract of Cnidoscolus diacanthus (Pax & K. Hoffm.) J.F. Macbr., known in Peru as "huanarpo hembra", and its effect on sex hormone levels. Its phytochemical profile was determined using liquid chromatography-mass spectrometry (LC-MS), while its total phenol content (TPC) and total flavonoids (TFs) were determined using the Folin-Ciocalteu method and the aluminum chloride method. Its antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), the radical 2,2-azino-bis-3-ethylbenzthiazolin-6 sulfonic acid (ABTS), and ferric-reducing antioxidant power (FRAP). The biological activity of C. diacanthus and its effect on sexual hormones were determined in Holtzman rats of both sexes. Phytochemical analysis revealed the presence of flavonoids and phenolic compounds in its leaves and stems, mainly rutin, quercetin, chlorogenic acid, and genistein. However, the stem extract contained higher total phenol (464.38 ± 4.40 GAE/g) and flavonoid (369.17 ± 3.16 mg QE/g of extract) contents than the leaf extract (212.38 ± 3.19 mg GAE/g and 121.49 ± 2.69 mg QE/g). For DPPH, ABTS, and FRAP, the Trolox-equivalent antioxidant capacity (TEAC) was 597.20 ± 5.40 µmol/g, 452.67 ± 5.76 µmol/g, and 535.91 ± 1.56 µmol/g, respectively, for the stems, while for the leaves, it was 462.39 ± 3.99 µmol/g, 202.32 ± 5.20 µmol/g, and 198.13 ± 1.44 µmol/g, respectively. In terms of the values for hormonal levels, at a dose of 100 mg/kg of the extract, testosterone levels of 1.430 ng/mL (with the leaf extract) and 1.433 ng/mL (with the stem extract), respectively, were found in the male rats. Regarding estradiol levels, in the female rats, these were 10.425 ng/mL (leaf extract) and 8.775 ng/mL (stem extract), while their levels of luteinizing hormone were 0.320 mIU/mL (leaf extract) and 0.273 mIU/mL (stem extract). For the follicle-stimulating hormone, levels of 0.858 mIU/mL (leaf extract) and 0.840 mIU/mL (stem extract) were found in the female rats, and levels of 0.220 mIU/mL (leaf extract) and 0.200 mIU/mL (stem extract) were found in the male rats. It is concluded that the C. diacanthus stem extract had a greater antioxidant capacity than the leaf extract, while both extracts had a superior effect on the sex hormone levels in the female rats compared to the male rats.
Subject(s)
Antioxidants , Plant Extracts , Plant Leaves , Plant Stems , Animals , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Leaves/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Rats , Male , Plant Stems/chemistry , Flavonoids/analysis , Flavonoids/chemistry , Flavonoids/pharmacology , Female , Peru , Gonadal Steroid Hormones/metabolism , Phenols/chemistry , Phenols/analysis , Phenols/pharmacology , Euphorbiaceae/chemistry , Phytochemicals/pharmacology , Phytochemicals/chemistry , Phytochemicals/analysisABSTRACT
Traditional pastures in temperate regions face limitations such as reduced growth and nutritional quality during the summer season. Plantain (P. lanceolata L.) offers advantages like increased yield and decreased nitrogen losses from grazing ruminants. Effective grazing management is essential for pasture health, and defoliation frequency and intensity play a pivotal role. This study aimed to evaluate plantain's regrowth, yield, and morpho-physiological and chemical responses under different defoliation frequencies and intensities, with the goal of enhancing its management in pastures. The study was conducted in pots within a controlled-environment growth chamber, examining the impact of three defoliation frequencies (based on extended leaf length: 15, 25 and 35 cm) and two defoliation intensities (5 and 8 cm of residual heights) with four replicates (24 pots as experimental units). The variables of interest were morphological characteristics, dry matter (DM) accumulation, herbage chemical composition, growth rate traits, and photosynthetic parameters. Defoliation frequency affected plantain's growth and nutritional composition. More frequent cuts (15 cm) resulted in lower DM yield per cut and lower stem content, while less frequent cuts (35 cm) produced higher values. Defoliation intensity influenced the proportion of leaves and stems in the total DM, with 5 cm cuts favoring leaves. Nutrient content was also affected by defoliation frequency, with less frequent cuts (35 cm) showing lower crude protein concentration and metabolizable energy content but higher neutral detergent fiber and water-soluble carbohydrate concentration. Plantain's growth rate variables were mainly influenced by defoliation frequency, with less frequent cuts promoting faster leaf appearance and growth of new leaves. The basal fluorescence variables and chlorophyll content were affected by cutting frequency, being highest when cut less frequently (35 cm), while no differences were found in the actual quantum efficiency among different defoliation frequencies and intensities. The fraction of light dedicated to non-photochemical quenching was highest when cut less frequently and more intensively. Overall, defoliation at 25 cm of extended leaf length balanced plantain forage quality and regrowth capacity.
Subject(s)
Plant Leaves , Plantago , Plantago/growth & development , Plantago/physiology , Plantago/metabolism , Plant Leaves/growth & development , Plant Leaves/anatomy & histology , Plant Leaves/metabolism , Photosynthesis , SeasonsABSTRACT
More catechins are found in green tea than in any other type of tea, with its predominant production taking place in Asian nations. Consumption of green tea has been strongly correlated with a reduced risk of many diseases. This study introduces a new, efficient, and reliable method for extracting total catechins using ultra-high-performance liquid chromatography coupled with an ID-X-Orbitrap Mass spectrometer (UHPLC-IDX-Orbitrap-MS). The method was then applied to quantify the catechin content in green tea, yielding results comparable to previously published studies. Among the various sources of green tea analyzed, the lowest average catechin content was observed in Vietnam, Japan (2: Matcha), and Morocco, ranging between 346 and 322 mg/L. Conversely, the highest average catechin content (between 424 and 422 mg/L) was found in Sri Lanka and Japan (1: Sencha). For the remaining green tea extracts, the catechin levels ranged from 367 to 410 mg/L, exhibiting similar values. These findings demonstrate the high reproducibility of the proposed extraction procedure, with a relative standard deviation (RSD) error of less than 15% for the catechin standard. Additionally, the limit of detection for catechins was determined to be 1 ng mL-1. This study serves as a pilot investigation for extracting catechins from various green tea sources. Future research will focus on identifying all active compounds present. Furthermore, it is worth noting that this study aligns with the goals set forth in Saudi Vision 2030, which aims to diversify the country's economy and promote scientific advancements in various fields, including healthcare and agriculture.
Subject(s)
Catechin , Mass Spectrometry , Plant Leaves , Tea , Catechin/analysis , Catechin/isolation & purification , Chromatography, High Pressure Liquid/methods , Tea/chemistry , Mass Spectrometry/methods , Reproducibility of Results , Plant Leaves/chemistry , Plant Extracts/chemistry , Plant Extracts/analysisABSTRACT
The herbicide mixture diclosulam + halauxifen appears to be an alternative for the control of Conyza spp.; however, the spray volume may result in different spray deposition effects on the target and, therefore, on the control. Therefore, the objective of this study was to evaluate the impact of different spray volumes of diclosulam + halauxifen on the control of and damage to the leaf surface of Conyza spp. The experiment was conducted in the field in a randomized block design with four replications. Diclosulam + halauxifen (23.52 g ai ha-1 + 6.32 g ae ha-1) was applied to Conyza spp. at average heights greater than 10 cm, followed by sequential application of glufosinate ammonium (500 g ai ha-1) after 14 days. Different spray volumes (200, 150, 100, 80 and 50 L ha-1) were used. The percentage of droplet coverage was evaluated using hydrosensitive paper and analyzed using DropScan software. After 24 hours of initial application, the leaves were collected for scanning electron microscopy (SEM). Although the different spray volumes did not affect the control, faster necrosis effects were observed at 150 and 200 L ha-1. Moreover, the trichome and stomatal density decreased at a spray volume of 200 L ha-1, indicating greater initial damage at this spray volume. Thus, increased spray spray volumes result in increased spray spray deposition, damage to leaf structures and consequently increased control speed.
Subject(s)
Conyza , Glycine max , Herbicides , Microscopy, Electron, Scanning , Plant Leaves , Conyza/drug effects , Time FactorsABSTRACT
In this work we reported injuries caused by the spider mite Oligonychus yothersi on Vitis vinifera leaves and we also investigate the sex ratio of this species under laboratory conditions. To access the aspects regarding reproduction, females were placed individually in arenas made of V. vinifera leaves to oviposit and all progeny were mounted on slides when they reached adulthood to confirm the offspring sex. Our study showed that O. yothersi reproduces by thelytokous /arrhenotokous parthenogenesis, generating low number of males. Additionally, we found vine plants with leaf browning, particularly on the adaxial surface, where mites were usually found.
Subject(s)
Reproduction , Sex Ratio , Tetranychidae , Animals , Tetranychidae/physiology , Tetranychidae/classification , Female , Male , Reproduction/physiology , Vitis/parasitology , Parthenogenesis/physiology , Plant Leaves/parasitologyABSTRACT
Olive trees not only produce olives but also generate a substantial amount of waste and by-products, including leaves, pomace (the solid remains after pressing olives for oil), and wastewater from the olive oil-making process. The waste products, particularly the leaves, contain bioactive compounds, especially phenolic compounds, known for their health benefits, such as high antioxidant potential and the ability to reduce inflammation. These compounds have shown promise in preventing and treating cancer. This review, based on in vitro evidence, provides a detailed description and discussion of the mechanisms through which these compounds from olive leaves can prevent development, the ways they might act against cancer cells, and their potential to increase the sensitivity of tumor cells to conventional anticancer therapy. The possible synergistic effects of these compounds suggest that olive leaf extracts may offer a promising approach for cancer treatment, compared with isolated compounds, thus providing novel possibilities for cancer therapy.
Subject(s)
Olea , Plant Extracts , Plant Leaves , Olea/chemistry , Plant Leaves/chemistry , Humans , Plant Extracts/pharmacology , Plant Extracts/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Neoplasms/drug therapy , Neoplasms/metabolism , Phenols/pharmacology , Phenols/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , AnimalsABSTRACT
Tea (Camellia sinensis), a perennial evergreen shrub, is one of the most important cash crops in China. Tea leaves with symptoms of wilt disease was observed in Fengqing County, Lincang City, Yunnan Province, China. Large irregular jujube-red necrotic spots appeared on the leaves of tea plants, and the lesions with grayish white edge were accompanied by a certain degree of shrinkage. In the tea garden planting base, the natural disease incidence reached 40%-50 %, which significantly affects the yield of tea. One putative pathogen was isolated from three symptomatic tea plant leaves and was identified as Discosia brasiliensis using morphology and molecular phylogeny of multi-loci (ITS, LSU, tub, rpb2) sequence data. Using D. brasiliensis strains for artificial inoculation assay on the tea plant leaves, leaf atrophy symptom in leaves which is similar to those observed in the tea planting base, and the putative pathogen was re-isolated to fulfill Koch's postulates. This is the first report of wilt disease caused by Discosia brasiliensis in China.
Subject(s)
Camellia sinensis , Phylogeny , Plant Diseases , Plant Leaves , Plant Diseases/microbiology , China , Plant Leaves/microbiology , Camellia sinensis/microbiology , Ascomycota/genetics , Ascomycota/isolation & purification , Ascomycota/classification , Ascomycota/pathogenicity , Sequence Analysis, DNA , DNA, Fungal/geneticsABSTRACT
Predicting how plants respond to drought requires an understanding of how physiological mechanisms and drought response strategies occur, as these strategies underlie rates of gas exchange and productivity. We assessed the response of 11 plant traits to repeated experimental droughts in four co-occurring species of central Australia. The main goals of this study were to: (i) compare the response to drought between species; (ii) evaluate whether plants acclimated to repeated drought; and (iii) examine the degree of recovery in leaf gas exchange after cessation of drought. Our four species of study were two tree species and two shrub species, which field studies have shown to occupy different ecohydrological niches. The two tree species (Eucalyptus camaldulensis Dehnh. and Corymbia opaca (D.J.Carr & S.G.M.Carr) K.D.Hill & L.A.S.Johnson) had large reductions in stomatal conductance (gs) values, declining by 90% in the second drought. By contrast, the shrub species (Acacia aptaneura Maslin & J.E.Reid and Hakea macrocarpa A.Cunn. ex R.Br.) had smaller reductions gs in the second drought of 52 and 65%, respectively. Only A. aptaneura showed a physiological acclimatation to drought due to small declines in gs versus á´ªpd (0.08 slope) during repeated droughts, meaning they maintained higher rates of gs compared with plants that only experienced one final drought (0.19 slope). All species in all treatments rapidly recovered leaf gas exchange and leaf mass per area following drought, displaying physiological plasticity to drought exposure. This research refines our understanding of plant physiological responses to recurrent water stress, which has implications for modelling of vegetation, carbon assimilation and water use in semi-arid environments under drought.
Subject(s)
Droughts , Plant Leaves , Trees , Plant Leaves/physiology , Trees/physiology , Australia , Plant Transpiration/physiology , Species Specificity , Acclimatization/physiologyABSTRACT
INTRODUCTION: Bisphenol A (BPA), an organic compound used to produce polycarbonate plastics and epoxy resins, has become a ubiquitous contaminant due to its high-volume production and constant release to the environment. Plant metabolomics can trace the stress effects induced by environmental contaminants to the variation of specific metabolites, making it an alternative way to study pollutants toxicity to plants. Nevertheless, there is an important knowledge gap in metabolomics applications in this area. OBJECTIVE: Evaluate the influence of BPA in French lettuce (Lactuca Sativa L. var capitata) leaves metabolic profile by gas chromatography coupled to mass spectrometry (GC-MS) using a hydroponic system. METHODS: Lettuces were cultivated in the laboratory to minimize biological variation and were analyzed 55 days after sowing (considered the plant's adult stage). Hexanoic and methanolic extracts with and without derivatization were prepared for each sample and analyzed by GC-MS. RESULTS: The highest number of metabolites was obtained from the hexanoic extract, followed by the derivatized methanolic extract. Although no physical differences were observed between control and contaminated lettuce leaves, the multivariate analysis determined a statistically significant difference between their metabolic profiles. Pathway analysis of the most affected metabolites showed that galactose metabolism, starch and fructose metabolism and steroid biosynthesis were significantly affected by BPA exposure. CONCLUSIONS: The preparation of different extracts from the same sample permitted the determination of metabolites with different physicochemical properties. BPA alters the leaves energy and membrane metabolism, plant growth could be affected at higher concentrations and exposition times.
Subject(s)
Benzhydryl Compounds , Gas Chromatography-Mass Spectrometry , Hydroponics , Lactuca , Metabolomics , Phenols , Plant Leaves , Benzhydryl Compounds/analysis , Lactuca/metabolism , Lactuca/drug effects , Lactuca/growth & development , Lactuca/chemistry , Gas Chromatography-Mass Spectrometry/methods , Plant Leaves/metabolism , Plant Leaves/drug effects , Phenols/metabolism , Phenols/analysis , Metabolomics/methods , Hydroponics/methods , Metabolome/drug effectsABSTRACT
The cajuzinho do cerrado (Anacardium humile-Anacardiaceae), a shrub species native to Brazil, is harvested for multiple uses in food and medicine. Members of a harvesting community, near the municipality of Bonito de Minas, Minas Gerais state, Brazil reported characteristic symptoms of shoot blight and dieback reducing pseudofruit and seed production by this plant. This study aimed to identify the etiological agent of this disease. Two fungal isolates were obtained from symptomatic leaf samples and morphologically and molecularly characterized. The fungus was identified, based on morphological analyses, as a probable new species of Pseudoplagiostoma. Phylogenetic analyses based on a combination of DNA sequence data (nuc rDNA ITS1-5.8S-ITS2 region, tef1-α and tub2), confirmed this hypothesis. The isolates obtained were allocated to a distinct, well-supported clade (IB = 0.99, ML = 100%), placed as a unique lineage here proposed as a new species named Pseudoplagiostoma humilis. The pathogenicity test confirmed that this new species was the causal agent of shoot blight and dieback on A. humile. This is the fourteenth Pseudoplagiostoma species reported in the world and the third in Brazil.
Subject(s)
Anacardium , DNA, Fungal , Phylogeny , Plant Diseases , Brazil , Plant Diseases/microbiology , Anacardium/microbiology , DNA, Fungal/genetics , Ascomycota/genetics , Ascomycota/classification , Ascomycota/isolation & purification , Ascomycota/physiology , Sequence Analysis, DNA , Plant Leaves/microbiology , DNA, Ribosomal Spacer/genetics , DNA, Ribosomal/geneticsABSTRACT
The aim of the present research was to evaluate the efficiency of different vegetation indices (VI) obtained from satellites with varying spatial resolutions in discriminating the phenological stages of soybean crops. The experiment was carried out in a soybean cultivation area irrigated by central pivot, in Balsas, MA, Brazil, where weekly assessments of phenology and leaf area index were carried out. Throughout the crop cycle, spectral data from the study area were collected from sensors, onboard the Sentinel-2 and Amazônia-1 satellites. The images obtained were processed to obtain the VI based on NIR (NDVI, NDWI and SAVI) and RGB (VARI, IV GREEN and GLI), for the different phenological stages of the crop. The efficiency in identifying phenological stages by VI was determined through discriminant analysis and the Algorithm Neural Network-ANN, where the best classifications presented an Apparent Error Rate (APER) equal to zero. The APER for the discriminant analysis varied between 53.4% and 70.4% while, for the ANN, it was between 47.4% and 73.9%, making it not possible to identify which of the two analysis techniques is more appropriate. The study results demonstrated that the difference in sensors spatial resolution is not a determining factor in the correct identification of soybean phenological stages. Although no VI, obtained from the Amazônia-1 and Sentinel-2 sensor systems, was 100% effective in identifying all phenological stages, specific indices can be used to identify some key phenological stages of soybean crops, such as: flowering (R1 and R2); pod development (R4); grain development (R5.1); and plant physiological maturity (R8). Therefore, VI obtained from orbital sensors are effective in identifying soybean phenological stages quickly and cheaply.
Subject(s)
Glycine max , Glycine max/growth & development , Neural Networks, Computer , Brazil , Crops, Agricultural/growth & development , Plant Leaves/growth & development , Algorithms , Discriminant AnalysisABSTRACT
Bacteriophages have been proposed as biological controllers to protect plants against different bacterial pathogens. In this scenario, one of the main challenges is the low viability of phages in plants and under adverse environmental conditions. This work explores the use of 12 compounds and 14 different formulations to increase the viability of a phage mixture that demonstrated biocontrol capacity against Pseudomonas syringae pv. actinidiae (Psa) in kiwi plants. The results showed that the viability of the phage mixture decreases at 44 °C, at a pH lower than 4, and under UV radiation. However, using excipients such as skim milk, casein, and glutamic acid can prevent the viability loss of the phages under these conditions. Likewise, it was demonstrated that the use of these compounds prolongs the presence of phages in kiwi plants from 48 h to at least 96 h. In addition, it was observed that phages remained stable for seven weeks when stored in powder with skim milk, casein, or sucrose after lyophilization and at 4 °C. Finally, the phages with glutamic acid, sucrose, or skim milk maintained their antimicrobial activity against Psa on kiwi leaves and persisted within kiwi plants when added through roots. This study contributes to overcoming the challenges associated with the use of phages as biological controllers in agriculture.
Subject(s)
Plant Diseases , Pseudomonas syringae , Pseudomonas syringae/virology , Pseudomonas syringae/drug effects , Plant Diseases/virology , Plant Diseases/prevention & control , Plant Diseases/microbiology , Agriculture/methods , Actinidia/chemistry , Bacteriophages/physiology , Microbial Viability/drug effects , Hydrogen-Ion Concentration , Biological Control Agents/pharmacology , Excipients/chemistry , Excipients/pharmacology , Plant Leaves/virology , Plant Leaves/chemistryABSTRACT
This study evaluated the foliar antioxidant activity in nine Hevea brasiliensis genotypes from the ECC-1 (Élite Caquetá Colombia) selection and IAN 873 cultivar (control) in trees in the growth stage in two large-scale clonal trials in response to different climatic (semi-humid warm and humid warm sites) and seasonal (dry and rainy periods) conditions in the Colombian Amazon. The results indicated that Reactive Oxygen Species (ROS) production increased under conditions of lower water availability (dry period), leading to lipid peroxidation, high defense of photosynthetic pigments, and development of better osmotic adjustment capacity in the ECC 64, IAN 873, ECC 90, and ECC 35 genotypes due to high concentrations of carotenoids (0.40 mg g-1), reducing sugars (65.83 µg mg-1), and malondialdehyde (MDA) (2.44 nmol ml-1). In contrast, during the rainy period, a post-stress action was observed due to high contents of proline and total sugars (39.43 µg g-1 and 173.03 µg g-1, respectively). At the site level, with high Photosynthetically Active Radiation (PAR) values (1143 moles photons m-2 s-1), temperature (32.11°C), and lower precipitation (135 mm), higher antioxidant activity (chlorophylls a, b and total, carotenoids, and proline) was recorded at the humid warm site, demonstrating that the ECC 90, ECC 64, and ECC 66 genotypes are tolerant to water deficit compared to IAN 873. The ECC 64 genotype, independent of seasonal changes and site conditions, presented the highest contents in Chl a, total Chl, reducing sugars, total sugars, and MDA, showing a tendency to adapt to fluctuating conditions. This study showed that water fluctuations do not cause the same metabolic responses, these vary within the same species, depending on their developmental stage and the climatic and seasonal variations characteristic of the Colombian Amazon.
Subject(s)
Antioxidants , Genotype , Hevea , Plant Leaves , Water , Antioxidants/metabolism , Colombia , Plant Leaves/genetics , Plant Leaves/metabolism , Water/metabolism , Hevea/genetics , Hevea/metabolism , Photosynthesis/genetics , Plant Breeding/methods , Carotenoids/metabolism , Reactive Oxygen Species/metabolism , Malondialdehyde/metabolism , Lipid Peroxidation , SeasonsABSTRACT
Soybean is an economically important crop for animal and human nutrition. Currently, there is a lack of information on the effects of Trichoderma harzianum and Purpureocillum lilacinum on INTACTA RR PRO transgenic soybean plants. The present study evaluated the application of T. harzianum and P. lilacinum under field conditions. The results revealed a significant increase in soybean yield at 423 kg ha-1 in response to the application of P. lilacinum compared with the control treatment. In addition, the application of P. lilacinum promoted a significant increase in phosphorus levels in the plant leaves, and there were significant correlations between the increase in taxon abundance for the genus Erwinia and productivity and the average phosphorus and nitrogen content for the plant leaves, for the taxon Bacillus and nitrogen content and productivity, and for the taxon Sphingomonas and nitrogen content. The Bradyrhizobium taxon was identified in the P. lilacinum treatment as a taxon linking two different networks of taxa and is an important taxon in the microbiota. The results show that the application of the fungus P. lilacinum can increase the productivity of soybean INTACTA RR PRO and that this increase in productivity may be a function of the modulation of the microbiota composition of the plant leaves by the P. lilacinum effect.
Subject(s)
Glycine max , Hypocreales , Microbiota , Nitrogen , Phosphorus , Glycine max/microbiology , Glycine max/growth & development , Glycine max/metabolism , Hypocreales/genetics , Hypocreales/growth & development , Hypocreales/metabolism , Nitrogen/metabolism , Phosphorus/metabolism , Plant Leaves/microbiology , Plants, Genetically ModifiedABSTRACT
The water relation strategy is a key issue in climate change. Given the difficulty of determining water relations strategy, there is a need for simple traits with a solid theoretical basis to estimate it. Traits associated with resource allocation patterns along a 'fast-slow' plant economics spectrum are particularly compelling, reflecting trade-offs between growth rate and carbon allocation. Avocado (Persea americana ), fig tree (Ficus carica ), mandarin (Citrus reticulata ), olive (Olea europaea ), pomegranate (Punica granatum ), and grapevine (Vitis vinifera ) were characterised in terms of iso-anisohydric strategy through stomatal behaviour, water potential at the turgor loss point (TLP), and hydroscape area. Additionally, the association of these metrics with leaf mass per area (LMA) and wood density (WDen) was explored. We observed high coordination between LMA and WDen, and both traits were related to metrics of water relation strategy. More anisohydric species tended to invest more carbon per unit leaf area or unit stem volume, which has implications for hydraulic efficiency and water stress tolerance. WDen and TLP were the most powerful traits in estimating the water relation strategy for six fruit species. These traits are easy to measure, time-cost efficient, and appear central to coordinating multiple traits and behaviours along the water relations strategies.