Nitrogen Balance Index Research Articles

Alteration of Metabolites Accumulation in Maize Inbreds Leaf Tissue under Long-Term Water Deficit.

Simple SummaryAs sessile organisms, plants are constantly exposed to diverse environmental stresses of which water deficit is the most significant because it limits plant growth, development, and productivity. In this work, we showed the influence of non-irrigation treatment on changes in maize leaf metabolite content. We argued that the different susceptibility of maize inbred lines to long-term water deficit will result in different patterns of change in metabolite accumulation. We emphasized the need for the careful interpretation of the level and type of accumulated metabolites in order to assess the drought tolerance status of maize inbred lines in terms of improved grain yield exhibited under severe water deficit conditions. Leaf metabolites that have contributed to higher grain yield under the condition of long-term water deficit could be considered as biochemical markers useful in breeding drought-tolerant maize.Plants reconfigure their metabolic pathways to cope with water deficit. The aim of this study was to determine the status of the physiological parameters and the content of phenolic acids in the upper most ear leaf of maize inbred lines contrasting in drought tolerance in terms of improved plant productivity e.g., increased grain yield. The experiment was conducted under irrigation and rain-fed conditions. In drought-tolerant lines, the effect of water deficit was reflected through a chlorophyll and nitrogen balance index increase followed by a flavonols index decrease. The opposite trend was noticed in drought susceptible inbreds, with the exception of the anthocyanins index. Moreover, in comparison to irrigation treatment, opposite trends in the correlations between grain yield and physiological parameters found under water deficit conditions indicated the activation of different metabolic pathways in defense against water deficit stress. Concerning phenolic acid content, water deficit caused the reduction of protocatechuic, caffeic, and sinapic acid in all inbreds evaluated. However, the highly pronounced increase of ferulic and especially cinnamic acid content under water deficit conditions indicated possible crucial role of these secondary metabolites in preventing the harmful effects of water deficit stress, which, in turn, might be useful in maize breeding selection for drought tolerance.

English

An investigation was carried out at the Department of Horticulture, University of Agricultural Sciences, Bangalore during summer-2017 to study the effect ofvaried levels of nitrogen and phosphorus fertigation on cherry tomato under open field and polyhouse conditions. There were 12 treatment combinations comprising of two growing conditions (open field and polyhouse), three levels of nitrogen (120, 150 and 180 kg N ha-1) and two levels of phosphorus (100 and 120 kg P2O5 ha-1) supplied trough fertigation with recommended potassium (150 kg h-1) as constant which were laid out in Factorial Randomized Complete Block Design with three replications. Result revealed that plant height (384.39 cm), fresh weight per plant (3.00 kg),nitrogen balance index (48.56), total leaf area per plant (6293 cm2), mean fruit weight (15.84 g), TSS content (6.30 ºB) and shelf life (15.66 days) were significantly higher under polyhouse condition with fertigation level of 180:120 kg N:P2O5 ha-1. However, significantly higher yield per hectare (78.16 t), Shelf life (15.66 days) and higher cost benefit ratio (4.81) were observed under open field condition with fertigation level of 150:120 kg N: P2O5 ha-1. Further, it can be concluded from the study that application of 150:120 kg N: P2O5 ha-1 through fertigation under open field condition is profitable during summer season in the Eastern Dry Zone of Karnataka.

Effects of Trichoderma harzianum on Photosynthetic Characteristics and Fruit Quality of Tomato Plants.

The beneficial role of fungi from the Trichoderma genus and its secondary metabolites in promoting plant growth, uptake and use efficiency of macronutrients and oligo/micro-nutrients, activation of plant secondary metabolism and plant protection from diseases makes it interesting for application in environmentally friendly agriculture. However, the literature data on the effect of Trichoderma inoculation on tomato fruit quality is scarce. Commercially used tomato cultivars were chosen in combination with indigenous Trichodrema species previously characterized on molecular and biochemical level, to investigate the effect of Trichoderma on photosynthetic characteristics and fruit quality of plants grown in organic system of production. Examined cultivars differed in the majority of examined parameters. Response of cultivar Gružanski zlatni to Trichoderma application was more significant. As a consequence of increased epidermal flavonols and decreased chlorophyll, the nitrogen balance index in leaves has decreased, indicating a shift from primary to secondary metabolism. The quality of its fruit was altered in the sense of increased total flavonoids content, decreased starch, increased Bioaccumulation Index (BI) for Fe and Cr, and decreased BI for heavy metals Ni and Pb. Higher expression of swolenin gene in tomato roots of more responsive tomato cultivar indicates better root colonization, which correlates with observed positive effects of Trichodrema.

Interactive Impacts of Temperature and Elevated CO2 on Basil (Ocimum basilicum L.) Root and Shoot Morphology and Growth

Recent evidence suggests that the effects of temperature significantly affect the growth and development of basil plants with detrimental impacts on yield. The current research investigated the interactive effects of varying temperature and CO2 levels on the shoot and root morphology and growth of early and late-season basil plants. Basil plants were subjected to control (30/22 °C), low (20/12 °C), and high (38/30 °C) temperature under ambient (420 μL L−1) and elevated (720 μL L−1) CO2 concentrations. Decreasing the temperature to 20/12 °C caused more adverse effects on the morphological traits of the early-season basil. Relative to the control treatments, low- and high-temperature stresses decreased 71 and 14% in marketable fresh mass, respectively. Basil exhibited an increase in plant height, node and branch numbers, specific leaf area, anthocyanin and nitrogen balance index, root tips, and root crossings when subjected to high-temperature stress. Furthermore, elevated CO2 affected many morphological features compared to ambient CO2 concentrations. The findings of this study suggest that varying the growth temperature of basil plants would more significantly impact the shoot and root morphologies and growth rates of basil than increasing the CO2 concentrations, which ameliorated the adverse impacts of temperature stress.

Influence of water shortage on apple seedling growth under different radiation composition

Abiotic stresses strongly impair plant development and might impose detrimental effects particularly on seedlings. Irradiance and water deficit are relevant factors, which affect performance of young plants under controlled conditions. In our study, we investigated the influence of water shortage combined with different radiation sources - light emitting diodes (LED) and compact fluorescence lamps (CFL) - on physiological and biochemical parameters of young apple plants. Stress responses were assessed by fluorescence-based indices, while relative water, chlorophyll (Chl), and proline content served as reference parameters. The watering regime had a higher impact on biochemical indicators than the radiation sources. Lower Chl content was determined in plants grown under LED both in control and in water deficit plants. Nitrogen balance index and nitrogen balance index with red radiation excitation showed similar patterns regarding leaf Chl results in relation to the radiation source, being higher under CFL. In contrast, the flavonol index was higher in plants cultivated under LED. Stomatal conductance and maximal photochemical efficiency emphasised a radiation quality effect with higher values for CFL. In conclusion, fluorescence indices related to nitrogen status and flavonol content are promising parameters to sense physiological impairments under the given conditions. However, discrepancies compared to previous studies might be related to the different plant species, the nature of dehydration, and the measuring conditions.

Synergy of Sentinel-2A and Near-proximal sensor data for deriving biochemical parameters of paddy at different growth stages

The biochemical parameters (i.e. chlorophyll and nitrogen content) of crops are essential to evaluate the health status and to monitor crop growth. The incorporation of near-proximal sensor data with satellite data has offered a new angle for rapid, detailed, and reliable assessment of crop biochemical parameters. This study aimed to utilize the higher spatial and spectral resolution of Sentinel-2A multi-spectral instrument (MSI) satellite data in conjunction with near-proximal sensor data to derive the chlorophyll (Chl) content and nitrogen balance index (NBI) of paddy at different growth stages during the monsoon season (2017) in Ranchi district, Jharkhand. The key findings revealed that the satellite-derived Chl content and NBI of paddy were overestimated as compared to the field-based measurements. The correlations between satellite-derived and empirical model-based Chl content and NBI of paddy revealed a R2 of 0.92–0.99 (p < 0.001) at different growth stages. The Chl content was found higher (20–40 µg/cm2) during the peak growing stage of paddy and subsequently, it decreased (< 20 µg/cm2) by the start of the ripening stage. The root-mean-square error between the empirical model and satellite-based Chl content was from 7.7 to 8.5 µg/cm2. Thereby, it can be concluded that the MSI sensor with three red-edge bands along with visible and near-infrared has a virtuous capability to quantify the crop biochemical parameters. However, it needs a bias correction to derive Chl content/NBI accurately. The adopted methods of retrieving biochemical parameters at different growth stages would be beneficial for decision-makers in agriculture monitoring and can be incorporated in crop growth modelling and yield predictions.

Seed Osmo-priming in Chickpea Enhances Seed Quality and Crop Performance under Normal and Water Deficit Conditions

Background: The average productivity of chickpea is quite low (939 kg/ha) because of several factors including its cultivation in rain fed/low moisture and marginal lands, low seed replacement rate (25.4%), use of old and low-quality seed by the majority of farmers. This in turn gives poor germination, delayed emergence and sick seedlings that lead to poor yield. Osmo priming of seed with different in-organic salts has been reported to improve the germination, speed of emergence, seedling vigour, growth and yield of different vegetable and field crops but information’s on response of seed priming with in-organic salts on enhancement of seed quality parameters and crop performance of naturally aged seeds of chickpea is lacking over a wide range of environmental conditions including normal and water deficit conditions.Methods: An experiment was conducted under laboratory as well as in plastic pots with 05 seed osmo- priming level, two varieties of chickpea (Ujjawal and JG-14) and two moisture level (Normal at field capacity and water deficit at half of the field capacity) during rabi season 2017-18 and 2018-19.at the Research farm of ICAR- IIPR Kanpur (U.P.) to study the influence of seed osmo-priming with in- organic salts on seed quality parameters and crop performance under normal and water deficit conditions. The observations were recorded on seed quality, growth and crop efficiency parameters at their appropriate time.Result: Osmo-priming of one-year-old chickpea seeds with KNO3, MgSO4, Ca(NO3)2 at 0.2% solution and tap water for 06 hours significantly enhanced the seed quality parameters in both the varieties evaluated under normal as well as under water deficit conditions over their respective control. Amongst, the priming agents used, KNO3 performed better than MgSO4, Ca(NO3)2 and tap water in respect of most of the seed quality parameters studied. Variety Ujjawal responded better the priming treatments than JG-14 under both normal and water deficit conditions. Osmo-priming treatments also showed the positive response in the enhancement of Nitrogen balance index (NBI), chlorophyll, Flavonols, Stomatal conductance, photosynthetic rate and transpiration rate in both the varieties evaluated under normal as well as water deficit condition.

THE GROWTH, PHOTOSYNTHETIC PARAMETERS AND NITROGEN STATUS OF BASIL, CORIANDER AND OREGANO GROWN UNDER DIFFERENT LED LIGHT SPECTRA

Growth, morphological parameters, photosynthetic performance and nitrogen status were investigated in leafy herbs grown in light-limited time in a greenhouse under different light spectra emitted by LEDs. Fluorescence-based sensors that detect crop N status and maximum photochemical efficiency of photosystem II were used in this study. Four light treatments with the ratio of Red, Blue and White LEDs including 1) R40 + B50 + W10, 2) R70 + B20 + W10, 3) R70 + B20 + W10 + Far-Red and 4) White LEDs as control were used in this study. Dominant red light and/or white LED lights at 200 µmol m–2 s–1 at plant level and a 12 h photoperiod provided the most favourable conditions for plant growth and development compared to a high proportion of blue light (R40 + B50 + W10). However, plants grown under a high proportion of blue light had a higher chlorophyll index and nitrogen balance index (NBI) than under dominant red light treatments. Our study indicates the significant potential of fluorescence-based sensors in photobiology research as well as in the production of leafy herbs under LED lights.

Effects of potassium-solubilizing bacteria promoting the growth of Lycium barbarum seedlings under salt stress.

We investigated the effects of potassium-releasing bacteria on physiological and bioche-mical characteristics of Lycium barbarum (Cultivar Ningqi 1) under salt stress, with an experiment with treatments following randomized block design. The treatments included control (CK), 100 mmol·L-1 NaCl stress (NaCl), 100 mmol·L-1NaCl stress+KSBGY01 bacteria (NaCl-M1), 100 mmol·L-1NaCl stress+KSBGY02 bacteria (NaCl-M2), and 100 mmol·L-1NaCl stress+KSBGY01+KSBGY02 (NaCl-M3). We measued chlorophyll content, polyphenol content, superoxide anion (O2-·) content, hydrogen peroxide (H2O2) content, soluble sugar content, antioxidant enzyme activity and sucrose metabolic enzyme activity of Lycium barbarum seedlings. Results showed that the presence of potassium bacteria increased the values of flavonoids (FLAV), fluorescence excitation than anthocyanins relative index (FERARI), anthocyanins (ANTH-RB), nitrogen balance index (NBI-G), decreased the contents of O2-· and H2O2, and improved soluble sugar content, catalase (CAT) activity, sucrose phosphate synthase (SPS) activity, sucrose synthase (SS) activity and invertase (INV) activity of leaves in Lycium barbarum seedlings under salt stress. Among all the treatments, the highest values of ANTH-RB and NBI-G, soluble sugar content, and activities of CAT, SPS, SS, and INV presented in NaCl-M2 treatment, the highest values of SPAD, FLAV, and FERARI presented in NaCl-M3 treatment, the highest activity of superoxide dismutase (SOD) presented in NaCl-M1 treatment, the highest activity of glutathione peroxidase (GSH-Px) presented in NaCl treatment, and the highest peroxisome (POD) activity presented in CK. The 14 significant physiological and biochemical indicators in the leaves of L. barbarum seedling were analyzed by grey system correlation degree method. Our results suggested that the weighted correlation degree of phy-siological and biochemical indices of L. barbarum inoculated potassium-solubilizing bacteria was higher than that under CK and NaCl treatments. The highest weighted correlation was observed in NaCl-M2 treatment. Therefore, adding KSBGY02 potassium-solubilizing bacteria could alleviate the salt stress for L. barbarum seedlings.

Association of spectroscopically determined leaf nutrition related traits and breeding selection in Sassafras tzumu

BackgroundPlant traits related to nutrition have an influential role in tree growth, tree production and nutrient cycling. Therefore, the breeding program should consider the genetics of the traits. However, the measurement methods could seriously affect the progress of breeding selection program. In this study, we tested the ability of spectroscopy to quantify the specific leaf nutrition traits including anthocyanins (ANTH), flavonoids (FLAV) and nitrogen balance index (NBI), and estimated the genetic variation of these leaf traits based on the spectroscopic predicted data. Fresh leaves of Sassafras tzumu were selected for spectral collection and ANTH, FLAV and NBI concentrations measurement by standard analytical methods. Partial least squares regression (PLSR), five spectra pre-processing methods, and four variable selection algorisms were conducted for the optimal model selection. Each trait model was simulated 200 times for error estimation.ResultsThe standard normal variate (SNV) to the ANTH model and 1st derivatives to the FLAV and NBI models, combined with significant Multivariate Correlation (sMC) algorithm variable selection are finally regarded as the best performance models. The ANTH model produced the highest accuracy of prediction with a mean R2 of 0.72 and mean RMSE of 0.10%, followed by FLAV and NBI model (mean R2 of 0.58, mean RMSE of 0.11% and mean R2 of 0.44, mean RMSE of 0.04%). High heritability was found for ANTH, FLAV and NBI with h2 of 0.78, 0.58 and 0.61 respectively. It shows that it is beneficial and possible for breeding selection to the improvement of leaf nutrition traits.ConclusionsSpectroscopy can successfully characterize the leaf nutrition traits in living tree leaves and the ability to simultaneous multiple plant traits provides a promising and high-throughput tool for the quick analysis of large size samples and serves for genetic breeding program.

Effects of Combined Biochar and Vermicompost Solution on Leachate Characterization and Nitrogen Balance from a Greenhouse Tomato (Solanum Lycopersicum) Cultivation Soil

ABSTRACT Both biochar (B) and vermicompost (V) can provide the soil with soluble organic matter. We evaluated the effect of B in reducing nitrate and dissolved organic carbon (DOC) losses from soil via leaching together with the effect of B combined with V solution (vermiwash) in increasing the efficiency of plant nitrogen. Tomato plants (Solanum lycopersicum L.) were cultivated in a greenhouse with soil under three different amendments (B, V and a mix BV). B was applied at a rate of 2% w/w corresponding to 34 t ha−1. V was applied at 25 mg per plant through fertigation. Leachate and soil were monitored in terms of nitrates and DOC throughout the trial (120 days), and plants and fruits were monitored in terms of nitrogen balance index (NBI) and dry matter biomass. B and BV significantly decreased NO3 –_N content in the leachate in all recovered times by 66.8% and 71.3%, respectively. In contrast, the absence of biochar in the V treatment led to a 38.1% increase in NO3 –_N concentration. Similar results were found for DOC content. The dry biomass of plants increased in B and BV treatments by 19.5 and 28.7%, respectively. The dry biomass of tomato fruits was enhanced by 18.5, 12.1, and 37% in V, B and BV treatments, respectively. Synergisms were found between the char material and complex organic compounds derived from the vermicompost process in terms of safeguarding the quality of the soil, the underground water, and the sustainability of crops.

Exogenous ethylene increases methane emissions from canola by adversely affecting plant growth and physiological processes

It is well known that ethylene affects plants; however, its regulatory role in plant-derived methane (CH4) has not been addressed. In this study, we determined the effects of exogenous ethylene on canola (Brassica napus L.) growth and physiological traits, endogenous ethylene, and aerobic methane emission. Plants were grown under experimental conditions (22/18 °C, 16 h light : 8 dark; 500 µmol photons·m−2·s−1) for 21 d and were exposed to exogenous ethylene for different durations (0, 1, or 2 h·d−1). Methane and ethylene emissions were measured after 7, 14, and 21 d, whereas growth and physiological traits were measured after 21 d. Overall, methane emissions decreased, but endogenous ethylene increased over time with exogenous ethylene. Plants treated with exogenous ethylene had decreased growth, biomass, gas exchange, chlorophyll fluorescence, photosynthetic pigments, and nitrogen balance index, but increased flavonoids. Both methane and ethylene were negatively correlated with most growth and physiological traits. In conclusion, this study revealed that exogenous ethylene significantly increased both endogenous ethylene and methane emissions. Plants exposed to exogenous ethylene were likely stressed and emitted methane, which increased with exposure time.

The effect of fullerene on the physiological and biochemical parameters of barley plants in hydroponic culture

The differences in the response to the action of fullerene of barley plants (Hordeum vulgare L., cultivar Yakub) grown in water culture (in distillated water or Knop’s nutrient solution) with the addition of fullerene C 60 (10 or 50 mg/l) were studied. The content of chlorophyll, flavonols, and nitrogen balance index (NBI) were evaluated in the 1st leaf during the growing. At the end of the experiment, the relative rate of water loss (RWL) by the leaves was determined, as well as the dry mass of the roots and shoots. The effect of fullerene on the physiological and biochemical parameters of barley plants depended on the concentration of these nanoparticles and the presence of nutrients in the cultivation medium. Under the action of 10 mg/l of fullerene, all investigated parameters were mainly maintained at the level of control values. At the same time, exposure to 50 mg/l of fullerene stimulated a decrease in the content of chlorophyll and flavonols in the first leaf, increased the relative loss of water by the leaves, and slowed down the growth of barley plants grown in water. When 50 mg/l of fullerene was added to the Knop solution, the chlorophyll content in the first leaf increased, the accumulation of flavonols practically did not change, and the NBI increase was more prolonged. In this case, the dry mass of shoots increased, and no significant changes in the relative loss of water by the leaves and root growth were noted. It is assumed that differences in the sensitivity of plants to fullerene during their growth in water and Knop’s nutrient solution are associated, on the one hand, with their anatomical, morphological, and physiological and biochemical characteristics, including the activity of detoxification mechanisms, and, on the other, with possible changes in physicochemical properties nanoparticles in a solution of salts, activation of the delivery of nutrients with the help of fullerene and the influence on the processes that cause the aging of the first leaf to slow down.

Biomagnetic Priming-Possible Strategy to Revitalize Old Mustard Seeds.

Different priming methods were developed to improve seed germination and the early growth of seedlings. This study aimed to examine the combined effect of bacterial inoculation and static magnetic field on white mustard (Sinapis alba L.) germination. A plant growth-promoting bacterial strain Bacillus amyloliquefaciens D5 ARV was used for biopriming. The static magnetic field of 90 mT was applied for 5 and 15 min. Analyses of abscisic acid, chlorophyll, anthocyanins, flavonoids content, nitrogen balance index, and bacterial indole-3-acetic acid were used to explain observed effects. Bacterial inoculation improved seed germination, whereas exposure to 90 mT for 15 min suppressed germination. Such an unfavorable effect was neutralized when the treatment with the static magnetic field was combined with bacterial inoculation. The highest germination percentage was a result of synergistic action of B. amyloliquefaciens D5 ARV and 15 min long exposure to 90 mT, which induced an increase of 53.20% in the number of germinated seeds. The static magnetic field induced the increase of bacterial indole-3-acetic acid production threefold times. Biomagnetic priming caused a metabolic shift from primary to secondary metabolism in the white mustard seedlings. An adequate combination of biological priming and static magnetic field treatment can be successfully used in old seed revitalization and germination improvements. © 2021 Bioelectromagnetics Society.

Application of a Combined Transmittance/Fluorescence Leaf Clip Sensor for the Nondestructive Determination of Nitrogen Status in White Cabbage Plants.

The correct fertilization of vegetable crops is commonly determined on the basis of soil and plant costly destructive analyses, demanding more sustainable non-invasive optical detection. Here, we tested the ability of the combined transmittance/fluorescence leaf clip Dualex device for determining the nitrogen (N) status of cabbage plants. Fully developed leaves from plants grown under different N rates of 0; 100; 200; 300 kg N ha−1 in 2018 and 2019 were measured in the field by the Dualex sensor twice a year in July and October. The chlorophyll (Chl) and nitrogen (nitrogen balance index, NBI) indices and the flavonols (Flav) index of the sensor were positively and negatively correlated to leaf nitrogen, respectively. Merging the two-years data, the NBI versus leaf N correlation was less point dispersed in October than July (R2 = 0.76 and 0.64, respectively). NBI was also correlated to cabbage yield, better in July than October. Our results showed that the multiparametric Dualex device can be used as precision agriculture tool for the early prediction of plant N and cabbage yield with economic advantage for the growers and reduced environmental contamination due to nitrate leaching.

Exploring the Potential of Meyerozyma guilliermondii on Physiological Performances and Defense Response against Fusarium Crown Rot on Durum Wheat.

Coating seeds with bio-control agents is a potentially effective approach to reduce the usage of pesticides and fertilizers applied and protect the natural environment. This study evaluated the effect of seed coating with Meyerozyma guilliermondii, strain INAT (MT731365), on seed germination, plant growth and photosynthesis, and plant resistance against Fusarium culmorum, in durum wheat under controlled conditions. Compared to control plants, seed coating with M. guilliermondii promoted the wheat growth (shoot and roots length and biomass), and photosynthesis and transpiration traits (chlorophyll, ɸPSII, rates of photosynthesis and transpiration, etc.) together with higher nitrogen balance index (NBI) and lower flavonols and anthocyanins. At 21 days post infection with Fusarium, M. guilliermondii was found to reduce the disease incidence and the severity, with reduction rates reaching up to 31.2% and 30.4%, respectively, as well as to alleviate the disease damaging impact on photosynthesis and plant growth. This was associated with lower ABA, flavonols and anthocyanins, compared to infected control. A pivotal function of M. guilliermondii as an antagonist of F. culmorum and a growth promoter is discussed.

МОРФОЛОГИЧЕСКИЙ И ФИЗИОЛОГО‑БИОХИМИЧЕСКИЙ ОТВЕТ РАСТЕНИЙ НА ОБРАБОТКУ УГЛЕВОДОРОДОКИСЛЯЮЩИМИ БАКТЕРИЯМИ НА ФОНЕ НЕФТЯНОГО ЗАГРЯЗНЕНИЯ

In the field experiment, the effect of hydrocarbon-oxidizing auxin-producing bacteria Enterobacter sp. UOM 3 and Pseudomonas hunanensis IB C7 on some morphological and biochemical indicators of stress in barley plants was studied. Stress is caused by oil entering the soil. Throughout the experiment, the pollutant had an inhibitory effect on the length and weight of roots and shoots of barley plants, as well as on the size of leaves. Under such conditions, bacterialization by each of the strains caused an elongation of shoots, an increase in the wet weight of roots and shoots, and an increase in the leaf surface index compared to untreated plants in contaminated soil. In addition, the P. hunanensis IB C7 strain had a positive effect on root length. In the presence of oil, an increase in the ABA content in plants was found, to a greater extent in the roots than in the shoots. The use of bacteria reduced the amount of the hormone to values comparable to that in plants in clean soil. The level of chlorophyll in plants growing in the presence of oil was lower than in the control variant, but inoculation with microorganisms contributed to its increase. The minimum amount of flavonoids was found in control plants. In the presence of oil, the amount of flavonoids increased and was higher in the treated plants. Thus, it was found that bacterization reduces the negative consequences for barley plants caused by the ingress of oil into the soil. This was manifested in the improvement of some morphological characteristics of inoculated plants and was accompanied by a change in a number of their physiological and biochemical characteristics. Key words: oil pollution, barley plants, bacterization, Enterobacter sp., Pseudomonas hunanensis, abscisic acid, chlorophyll, flavonoids, nitrogen balance index.

Diversity Analysis of Chlorophyll, Flavonoid, Anthocyanin, and Nitrogen Balance Index of Tea Based on Dualex

The chemical compositions of tea (Camellia sinensis) are affected by numerous factors, such as cultivar, climate, leaf position, and cultivation pattern. However, under the same conditions, the chemical compositions are mainly determined by varieties. Therefore, we investigated the genetic diversity of chemical compositions of tea tree resources in China to screen excellent germplasm resources. Three chemical compositions index (including chlorophyll index, flavonoid index, and anthocyanin index) and the nitrogen balance index of tea leaves were measured in 102 tea germplasms planted in Chinese Tea Plants Improved Variety Germplasm Resources Nursery (CTPIVGRN) by Dualex on April 15 2019. Results showed that the chlorophyll, flavonoid, and anthocyanin contents and the nitrogen balance index significantly differed between the 102 tea germplasms. The genetic diversity index values were 2.005, 2.246, 1.599, and 1.838, and the average genetic diversity was 1.922. The 102 tea germplasms can be divided into four categories by cluster analysis under the genetic distance threshold of 11. These results suggest that the genetic diversity of tea germplasm resources in China is rich. This study’s results can serve as a basis for the diversified development and utilization of tea plant.

Individual and interactive effects of temperature and light intensity on canola growth, physiological characteristics and methane emissions

Earlier studies have shown that plants produce methane (CH4) under aerobic conditions, and that this emission is not microbial in nature. However, the precursors of aerobic CH4 remain under debate, and the combined effects of environmental factors on plant-derived CH4 requires further attention. The objective of this study was to determine the interactive effects of temperature and light intensity on CH4 and other relevant plant parameters in canola (Brassica napus L.). Plants were grown under two temperature regimes (22/18 °C and 28/24 °C, 16 h light/8 h dark) and two light intensities (300 and 600 μmol photons m−2 s−1) for 21 days after one week of growth under 22/18 °C (16 h light/8 h dark). In this study, higher temperature had little effects on CH4 emissions from plants, indicating the mitigating effects of higher light intensity. Higher light intensity, however, significantly decreased CH4, which was inversely related to plant dry mass. Higher light intensity decreased stem height, leaf area ratio, chlorophyll, nitrogen balance index, leaf moisture, methionine (Met) and ethylene (C2H4), but increased specific leaf mass, photochemical quenching, flavonoids, epicuticular wax, lysine and tyrosine. The results revealed that increased CH4 emissions from plants could be related to changes in plant physiological activities, which portrayed themselves in increased C2H4 evolution, and methylated amino acids, such as Met. We conclude that higher light intensity reduces Met and, in turn, CH4 and C2H4 emissions, but lower light intensity enhances CH4 formation through cleavage of methyl group of amino acids by reactive oxygen species, as previously suggested.

Chitosan Hydrochloride Decreases Fusarium graminearum Growth and Virulence and Boosts Growth, Development and Systemic Acquired Resistance in Two Durum Wheat Genotypes.

Fusarium head blight (FHB) is a devastating disease for cereals. FHB is managed by fungicides at anthesis, but their efficacy is variable. Conventional fungicides accumulate in the soil and are dangerous for animal and human health. This study assayed the antifungal ability of chitosan hydrochloride against Fusarium graminearum. Chitosan reduced F. graminearum growth and downregulated the transcript of the major genes involved in the cell growth, respiration, virulence, and trichothecenes biosynthesis. Chitosan promoted the germination rate, the root and coleoptile development, and the nitrogen balance index in two durum wheat genotypes, Marco Aurelio (FHB-susceptible) and DBC480 (FHB-resistant). Chitosan reduced FHB severity when applied on spikes or on the flag leaves. FHB severity in DBC480 was of 6% at 21 dpi after chitosan treatments compared to F. graminearum inoculated control (20%). The elicitor-like property of chitosan was confirmed by the up-regulation of TaPAL, TaPR1 and TaPR2 (around 3-fold). Chitosan decreased the fungal spread and mycotoxins accumulation. This study demonstrated that the non-toxic chitosan is a powerful molecule with the potential to replace the conventional fungicides. The combination of a moderately resistant genotype (DBC480) with a sustainable compound (chitosan) will open new frontiers for the reduction of conventional compounds in agriculture.