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The overuse of chemical fertilizers can harm soil decomposition organisms, decrease mycorrhizal colonization, and suppress nitrogen fixation through excessive nitrogen application. It is also expensive and contributes to environmental degradation, ecosystem instability, and the accumulation of heavy metals in soils and crops. Therefore, it is important to the resurgence to apply organic fertilization and nano fertilizers to lessen the reliance on the utilization of chemical fertilizers, produce healthy products, improve fruit quality, maintain soil fertility and microbial biomass, and consequently improve soil fertility and fruit productivity. In the current study, organic compost was added to the soil at 0, 2, and 3 kg/tree singly and in combination with the spraying of nanoparticles from boron and zinc at 50, 100, and 150 mg/L and nano potassium (K) at 100, 200, and 300 mg/L. The results showed that the addition of 3 kg compost to the soil combined with 150 mg/L ZnO + 150 mg/L B2O3 + 300 mg/L K2O (T12), or 100 mg/L ZnO + 100 mg/L B2O3 + 200 mg/L K2O (T11), and the addition of 2 kg soil combined with 150 mg/L ZnO + 150 mg/L B2O3 + 300 mg/L K2O (T8) and with 100 mg/L ZnO + 100 mg/L B2O3 + 200 mg/L K2O (T7) greatly improved the vegetative growth, yield, fruit quality, soil fertility, and nutritional status of the trees compared to the other applied treatments, and the addition of 3 kg compost to the soil combined with 150 mg/L ZnO + 150 mg/L B2O3 + 300 mg/L K2O (T12) was the superior formula in the two seasons. [ABSTRACT FROM AUTHOR]

One of the environmental problems that affects negatively orange productivity is drought because it greatly minimizes the growth attributes, photosynthetic process, water uptake, percentage of fruit set, and productivity; meanwhile, it raises the rates of respiration and transpiration, as well as the premature and preharvest fruit drop percentages. In addition, drought creates osmotic stress, affects the relationship between plants and water, reduces the amount of water in shoots, and prevents plant cell development and expansion. It is very important to search for a solution to minimize the effect of drought stress; therefore, the present study has investigated the effect of the application of humic acid (HA) at 0, 1 and 2 kg per tree and spraying of seaweed extract (SWE) at 0.2, 0.3 and 4% in combination with moringa leaf extract (MLE) at 2, 4 and 6%, respectively, on the productivity, fruit quality and nutritional status of navel orange cv. Washington during the 2022 and 2023 seasons. The results proved that the application of the biostimulants individually or in combination significantly positively changed the vegetative growth, productivity, fruit quality parameters and leaf mineral content of macro- and micronutrients of the treated trees compared to untreated trees. The superior treatments which gave the best results were 2 kg HA + 0.4% SWE + 6% MLE followed by 2 kg HA + 0.3% SWE + 4% MLE over the rest of the applied treatments. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate how the combined presence of the synthetic fungicide azoxystrobin (AZ) and the biosurfactant-producing Bacillus sp. Kol B3 influences the growth of the phytopathogenic fungus Fusarium sambucinum IM 6525. The results showed a noticeable increase in antifungal effectiveness when biotic and abiotic agents were combined. This effect manifested across diverse parameters, including fungal growth inhibition, changes in hyphae morphology, fungal membrane permeability and levels of intracellular reactive oxygen species (ROS). In response to the presence of Fusarium and AZ in the culture, the bacteria changed the proportions of biosurfactants (surfactin and iturin) produced. The presence of both AZ and/or Fusarium resulted in an increase in iturin biosynthesis. Only in 72 h old bacterial–fungal co-culture a 20% removal of AZ was noted. In the fungal cultures (with and without the addition of the bacteria), the presence of an AZ metabolite named azoxystrobin free acid was detected in the 48th and 72nd hours of the process. The possible involvement of increased iturin and ROS content in antifungal activity of Bacillus sp. and AZ when used together are also discussed. Biosurfactants were analyzed by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Microscopy techniques and biochemical assays were also used. [ABSTRACT FROM AUTHOR]

Salinity is a major social, economic, and environmental menace in climates with low rainfall and high evapotranspiration, and it influences plant growth and causes restriction to crop production in the world. Additionally, under salinity stress, numerous physiological processes such as photosynthesis, biomass accumulation, and photosynthate transfer are also harshly lessened, and it also limits the absorption of adequate water by plants and leads to a dimension in plant water status. Therefore, the current study was conducted to investigate the soil application of humic acid (HA) at 0, 0.5, 1 and 2 kg/tree alone or in combination with the foliar spraying of 0 mg ZnO2 + 0 mg TiO2, 200 mg ZnO2 + 60 mg TiO2 and/or 300 mg ZnO2 + 80 mg TiO2 through the two successive seasons 2022 and 2023. The results demonstrated that the use of HA alone or in combination with the spraying of TiO2 and ZnO2 greatly improved the leaf chlorophyll, flower number, fruit set percentages, fruit yields in kg or in ton per hectare, fruit weight, fruit size, and fruit firmness. Additionally, the same used treatments greatly improved the fruit content from TSS and oil percentages and also the leaf mineral content from N, P and K, while they minimized the fruit drop percentage and fruit moisture content as compared to control. The most positive influence was observed with the soil implementation of 2 kg HA combined with 300 mg ZnO2 + 80 mg TiO2 in the two experimental seasons. [ABSTRACT FROM AUTHOR]

Drought presents a critical challenge to global crop production, exacerbated by the effects of global warming. This study explores the role of rhizospheric bacteria (Bacillus, Pantoea, and Pseudomonas) in enhancing the drought resistance and nutrient absorption of strawberry plants. The experimental approach involved inoculating plant roots with various strains of rhizobacteria and assessing their impact under different water potential conditions in two substrates: optimal moisture and water deficit. The results showed significant changes in the nutrient content of strawberry plants, influenced by the type of bacterial strain and moisture conditions. Phosphorus and potassium content in the leaves varied considerably, with the highest levels observed in plants inoculated with specific bacterial strains under both optimal and water-deficit conditions. Similarly, calcium and magnesium content in the leaves also changed notably, depending on the bacterial strain and moisture level. The water deficit cluster, featuring the PJ1.1, DKB63, and DKB65 strains, showed PGPR's role in maintaining nutrient availability and plant resilience. The study demonstrates that inoculation with PGPR can markedly influence the nutrient profile of strawberry plants. These findings underscore the potential of using rhizobacteria to enhance crop resilience and nutritional status, especially in the context of increasing drought conditions due to climate change. [ABSTRACT FROM AUTHOR]

We aimed to investigate the contribution of co-translational protein aggregation to the chemotherapy resistance of tumor cells. Increased co-translational protein aggregation reflects altered translation regulation that may have the potential to buffer transcription under genotoxic stress. As an indicator for such an event, we followed the cytoplasmic aggregation of RPB1, the aggregation-prone largest subunit of RNA polymerase II, in biopsy samples taken from patients with invasive carcinoma of no special type. RPB1 frequently aggregates co-translationally in the absence of proper HSP90 chaperone function or in ribosome mutant cells as revealed formerly in yeast. We found that cytoplasmic foci of RPB1 occur in larger sizes in tumors that showed no regression after therapy. Based on these results, we propose that monitoring the cytoplasmic aggregation of RPB1 may be suitable for determining—from biopsy samples taken before treatment—the effectiveness of neoadjuvant chemotherapy. [ABSTRACT FROM AUTHOR]

Aspergillus parasiticus and Aspergillus ochraceus are important pathogenic fungi that pose a serious threat because of their ability to produce mycotoxins, including ochratoxin A (OTA) and aflatoxins (AFs). The main method of reducing these pathogens is the use of chemical fungicides, though recently there has been a focus on finding biological control agents. The obtained results from this study indicate the great potential of two wild yeast strains, Aureobasidium pullulans PP3 and Saitozyma podzolicus D10, in the biological control of A. parasiticus and A. ochraceus and reductions in the amount of OTA and AFs they produce. In vitro, the growth of the mycelium of pathogens was reduced by 41.21% to 53.64%, and spore germination was inhibited by 58.39% to 71.22%. Both yeast strains produced the enzymes chitinase, β-1,3-glucanase, and amylase, and A. pullulans PP3 additionally produced protease and cellulase. This yeast strain also had the ability to grow over a wide range of temperature (4–30 °C), salinity (0–12%) and pH (4–11) conditions. No growth of the yeast was observed at 37 °C, nor any biogenic amines or hydrogen sulfide production. Adding the tested yeast inoculum to the dough reduced OTA (within 14.55–21.80%) and AFs (within 18.10–25.02%) in the model bread. [ABSTRACT FROM AUTHOR]

Although chemical fertilization has been excessively used for a high yield of fruit trees, it causes many problems such as nitrate accumulation, soil deterioration, and food safety and quality decline; therefore, the dependency on the usage of biostimulants has become paramount when aiming to reduce the usage of chemical fertilizers, improve the fruit quality, and increase the shelf life of the fruits. The present experiment was conducted during the 2021–2022 seasons to study the effect of the foliar of yeast extract (YE), fulvic acid (FA), moringa leaf extract (MLE), seaweed extract (SWE), and nano-potassium (K NPs) alone or after combining each one of them individually with K NPs on the yield and fruit physical and chemical characteristics of date palm cv. Samani. The results show that the application of 0.2% YE + 0.02% K NPs led to the highest results in yield, bunch weight, fruit weight, flesh weight, fruit content from soluble solids, total and reduced sugars, VC, total chlorophyll, and carotene. Additionally, the results also demonstrate that the application of 0.4% SWE + 0.02% K NPs, 0.4% FA + 0.02% K NPs, and 6% MLE positively affected the previously mentioned measurements compared with the control or the other sprayed treatments. [ABSTRACT FROM AUTHOR]

Drought conditions pose significant challenges to sustainable agriculture and food security. Identifying microbial strains that can mitigate drought effects is crucial to enhance crop resilience and productivity. This study presents a comprehensive comparison of several machine learning models, including Random Forest, Decision Tree, XGBoost, Support Vector Machine (SVM), and Artificial Neural Network (ANN), to predict optimal microbial strains for this purpose. Models were assessed on multiple metrics, such as accuracy, standard deviation of results, gains, total computation time, and training time per 1000 rows of data. Notably, the Gradient Boosted Trees model outperformed others in accuracy but required extensive computational resources. This underscores the balance between accuracy and computational efficiency in machine learning applications. Leveraging machine learning for selecting microbial strains signifies a leap beyond traditional methods, offering improved efficiency and efficacy. These insights hold profound implications for agriculture, especially concerning drought mitigation, thus furthering the cause of sustainable agriculture and ensuring food security. [ABSTRACT FROM AUTHOR]

Arid and semi-arid soils are low in organic matter and have poor fertility, making them a serious threat to crop production. Most organic amendments, such as crop residues and farmyard manure, are short lived because of rapid decomposition. Incubation and pot studies were conducted to assess the impact of wheat straw biochar (produced at 350 °C) on temporal changes in soil microbial biomass and fertility status and to evaluate the efficacy of biochar for maize production in the top layer of Typic calciargid. The incubation study compared four levels of biochar (control, 0.5, 1.0 and 2.0% on a w/w basis of soil) and two fertilizer rates, i.e., unfertilized (no NPK fertilizer) and fertilized (nitrogen, P2O5 and K2O with rates of 125, 80 and 52.5 mg kg−1 soil, respectively). After incubation, the 2.0% biochar significantly improved the soil cation exchange capacity, organic carbon and microbial biomass carbon by up to 35, 59 and 26%, respectively, while decreasing the soil pH by up to 1.5% compared to that of the control treatment. When fertilized, the 2.0% biochar improved the soil's available phosphorous, extractable potassium and total nitrogen by up to 59, 39 and 28%, respectively, compared to those of the control. The results from the pot experiment showed that using the 1% biochar with fertilizer significantly increased the maize dry biomass and grain yield by up to 57 and 72%, respectively, compared to those of the control. Additionally, the nitrogen and phosphorus recoveries from the mineral fertilizers improved significantly (up to 26 and 38%, respectively) when using the 1.0% biochar compared to those of the control. Conclusively, the addition of 1.0% biochar significantly improved maize growth and yield by enhancing nutrient recovery from mineral fertilizer and improving soil properties. [ABSTRACT FROM AUTHOR]

A study conducted over three consecutive years examined the effects of using biochar, organic fertilizer and microorganisms on soil pH and the concentrations of macro and microelements in the soil. A tendency to increase soil pH was seen where biochar was used. The highest concentration of phosphorus was found in the soil after the application of organic fertilizer with the addition of microorganisms. The most potassium was found in the soil treated with biochar together with organic fertilizer, while the most magnesium was in the soil fertilized with organic fertilizer alone and organic fertilizer together with microorganisms. All the fertilization combinations resulted in an increase in boron and copper levels in the soil. The accumulation of iron in the soil was promoted by organic fertilization alone and organic fertilization together with microorganisms. The highest amount of manganese in the soil was found after fertilization with biochar together with organic fertilizer. In the combination where organic fertilizer was applied, the soil contained the most sodium, while the highest zinc content was found in the soil fertilized with biochar and organic fertilizer. The greatest increase in the carbon content in the soil occurred after the use of biochar together with microorganisms and biochar with organic fertilizer. The same treatments also resulted in the highest amount of organic matter. The study shows that the use of biochar, organic fertilization and the combined use of biochar and organic fertilization improved the quality of the soil. [ABSTRACT FROM AUTHOR]

The old Zn-Pb-contaminated (calamine) tailings in southern Poland are spontaneously colonized by metal-tolerant Anthyllis vulneraria L. (Fabaceae), which can form simultaneously symbiotic association with nitrogen-fixing rhizobia and phosphorus-acquiring arbuscular mycorrhizal fungi (AMF). So far, fungal colonization and the AMF diversity of calamine-inhabiting legumes have been poorly studied. Thus, we determined AMF spore density in the substratum and the mycorrhizal status of nodulated A. vulneraria plants occurring on calamine tailings (M) and on a reference non-metallicolous (NM) site. The results indicate the presence of the Arum-type of arbuscular mycorrhiza in the roots of both Anthyllis ecotypes. Despite the presence of AM fungi in M plant roots, the dark septate endophyte (DSE) fungi (hyphae and microsclerotia) were occasionally also detected. Metal ions were accumulated mainly in the nodules and intraradical fungal structures rather than thick plant cell walls. Mycorrhization parameters (frequency of mycorrhization and intensity of root cortex colonization) for M plants were markedly higher and differed in a statistically significant manner from the parameters for NM plants. Heavy metal excess had no negative effect on the number of AMF spores, the amounts of glomalin-related soil proteins and AMF species composition. Molecular identification of AMF using PCR-DGGE analysis based on the 18S rDNA ribosomal gene by nested-PCR with primers AM1/NS31 and NS31-GC/Glo1 revealed similar genera/species of AMF in the roots of both Anthyllis ecotypes: Rhizophagus sp., R. fasciculatus, and R. iranicus. The results of this work indicate the presence of unique fungal symbionts, which may enhance A. vulneraria tolerance to heavy metal stress and plant adaptation to extreme conditions on calamine tailings. [ABSTRACT FROM AUTHOR]

The content of macro and microelements in the leaves of peach trees treated with biochar, organic fertilization and microorganisms in the field experiment was tested. The experiment was carried out in accordance with the integrated fruit production methods at the NIHR Experimental Orchard in Dąbrowice, from 2015 to 2017. The trees were grafted on P. persica Mandżurska rootstock and planted in the spring of 2013. In 2014, the following products were applied around the trees and mixed into the topsoil: biochar at a dose of 1.6 kg/tree (2000 kg/ha); biochar at a dose of 1.6 kg/tree used together with microorganisms—bacteria Pseudomonas fluorescens, Pantoea and arbuscular mycorrhizal fungi—Glomus caledonium, Glomus intraradices and Glomus coronatum; biochar at a dose of 1.6 kg/tree applied together with Florovit NPK organic fertilizer at a dose of 0.2 kg/tree; Florovit NPK; microorganisms—bacteria Pseudomonas fluorescens, Pantoea and arbuscular mycorrhizal fungi—Glomus caledonium, Glomus intraradices and Glomus coronatum; Florovit NPK organic fertilizer with the same microorganisms; and an untreated control. The average results showed that, compared to the control, the biochar increased the nitrogen content in the leaves by 6%. All experimental combinations increased the content of P and K in the leaves. The most effective at increasing the content of phosphorus in leaves—by 48%—was Florovit. The greatest increase in potassium was after the use of biochar with Florovit—by 38%. The magnesium content ranged from 0.49 to 0.59 g/100 g DW. The highest content of Mg was found in the leaves after the application of biochar with Florovit, and the lowest after the use of biochar alone. The leaves of the trees fertilized with the Florovit organic fertilizer had the lowest calcium content, while the highest calcium content was found in combination with trees treated with biochar only. The use of biochar alone did not increase the content of boron in the leaves compared to the control. In all other combinations, a higher amount of boron was found. The highest—18% more than the control of this microelement had leaves where biochar and Florovit were used. Trees treated with biochar and microorganisms accumulated the least copper in the leaves, while the highest content of this element was found in the combination where biochar fertilization was applied together with Florovit. Lower iron concentrations in peach leaves were found as a result of applying microorganisms, microorganisms with the organic fertilizer and biochar, relative to organic fertilization and the control combination. Trees where only microorganisms were applied to the soil had the least manganese and zinc in the leaves. The accumulation of manganese in the leaves was most favored by fertilization with biochar together with microorganisms, and the zinc content was the highest after the use of biochar alone. In general, studies have shown that a small dose of biochar alone or biochar together with organic fertilizer is a very effective method of feeding peach trees. More research is needed on the use of microorganisms and methods of their application with various products used in orchard fertilization. [ABSTRACT FROM AUTHOR]

The excessive use of chemical fertilizers in fruit orchards has led to numerous problems for the environment, produce quality, and food safety. It also negatively affects soil health, beneficial microorganisms, and ground water quality, hence the resurgence of the application of biostimulants as ecofriendly ways to improve the growth, yield, and fruit quality of tree fruits. The current study was performed during 2021 and 2022 to investigate the influence of foliar spraying of 500, 1000, and 2000 mg/L humic acid (HA); 0.5, 1, and 2 mg/L brassinosteroids (Brs); and 1000, 2000, and 3000 mg/L seaweed extract (SWE) compared with a control (untreated trees) in terms of the performance of an apricot (Prunus armeniaca) cv. Canino. The obtained results show that the spraying of HA, Brs, and SWE positively increased the shoot length, leaf area, leaf chlorophyll content, fruit set, fruit yields, and fruit physical and chemical characteristics, as well as leaf macro- or micronutrients contents compared with those untreated trees during both study years. Moreover, the increase in parameter values was parallel to the increase in the used concentrations of HA, Brs, or SWE, where 2000 mg/L HA, 2 mg/L Brs, and 3000 mg/L SWE were superior to 1000 mg/L HA, 1 mg/L Brs, and 2000 mg/L SWE, which were better than 500 mg/L HA, 0.5 mg/L Brs, and 1000 mg/L SWE. [ABSTRACT FROM AUTHOR]

Effective management is crucial to achieve the high yield potential of quinoa (Chenopodium quinoa Willd.), renowned for its resilience in harsh environments, to meet the rising global demand. The present study examines how varying levels of water and nitrogen affect the agronomic and yield traits of quinoa (cv. Q-36) during the two growing seasons of 2020/2021 and 2021/2022. The experiment was a 3 × 4 factorial laid out in a randomized complete block design with three replications per treatment during the two seasons of the study, as water regimes were considered the main factor, including 100%, 80%, and 60% ETc, whereas nitrogen levels were considered the sub-plot factor, comprising four levels (75, 150, 225, and 300 kgN ha−1). The analysis of variance indicated that nitrogen level, irrigation regime, and irrigation regime × nitrogen level had highly significant effects (p < 0.001) on all studied traits, including plant height, panicle length, dry weight, seed weight, seed yield, and total yield in the two growing seasons under study. For all traits of study, the combined application of 100% ETc with 300 kgN, followed by 80% ETc with 225 kgN, resulted in the highest value of plant height, panicle length, dry weight, seed weight, seed yield, and total yield, whereas the combination of 60% ETc and 75 kgN applications resulted in the lowest value for all of the aforementioned traits. Furthermore, the water regime impacted water productivity at all nitrogen levels as the highest productivity level was recorded under the 80% ETc (0.58 kg/m3), followed by the 100% ETc (0.54 kg/m3), and the 60% ETc (0.52 kg/m3). The highest water productivity rate was observed at 300 kg/ha of the nitrogen levels for 60% and 80% ETc regimes, where water productivity levels were 0.73 and 0.71 (kg/m3), respectively. The results also indicate that the water productivity of quinoa plants is noticeably affected by both water regime and nitrogen level; as the water regimes decrease from 100% to 60% ETc, water productivity increases for all nitrogen levels. The information obtained from these results can be applied to optimize the methods for cultivating quinoa under conditions of water scarcity and minimal nitrogen availability, thus gaining an insight into the impact of these conditions on quinoa growth and yield. [ABSTRACT FROM AUTHOR]

One of the main causes of climate change is the emission of GHGs, and one of the sources for the generation of such gasses is agriculture via plant production. Considering the foregoing, a study was conducted to assess PGPRs in strawberry cultivation which were able to limit GHG emissions. The first experimental factor was the inoculation of plant roots with the Bacillus sp. strains DLGB3, DKB26, DKB58, and DKB 84; the Pantoea sp. strains DKB63, DKB64, DKB65, and DKB68; Azotobacter sp. AJ 1.2; and Pseudomonas sp. PJ 1.1. The second experimental factor constituted the different moisture levels of the growth substrate. In the experiment, emissions of NH3, CO2, N2O, and CH4 were measured. In light of the conducted research, five strains were selected (Azotobacter sp. AJ 1.2; Pantoea sp. DKB64, DKB63, and DKB68; and Pseudomonas sp. strain PJ 1.1) that showed the greatest potential for reducing GHG emissions depending on the prevailing environmental conditions. The application of the tested bacterial strains under different moisture conditions in the substrate either reduced or did not affect GWP. This research on PGPR, which was conducted to select strains of rhizosphere bacteria that would be able to reduce GHG emissions, may form the basis for creating an inoculum and can be employed as an effective strategy for mitigating certain abiotic stresses. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of fish farm wastewater from the production of hybrid sturgeon (Acipenser gueldenstaedtii Brandt × Acipenser baeri Brandt) on the growth and quality parameters of romaine lettuce (Lactuca sativa var. longifolium cv. "Elizium"). The tested combinations were fish farm wastewater, fish farm wastewater enriched with one of the three microbiological consortia, and fish farm wastewater supplemented with minerals. The best growth parameters of romaine lettuce plants were obtained in the combination of wastewater from fish farming supplemented with mineral nutrients. The application of fish farm wastewater and beneficial microbiological consortia positively influenced the fresh weight of lettuce leaves and the number of leaves per plant. However, plants fed with wastewater supplemented with minerals were characterized by the strongest symptoms of leaf tip-burn and the lowest commercial value. By comparison, plants fed only with fish farm wastewater or wastewater with microorganisms were characterized by a high, similar commercial value. After the application of increased doses of minerals, there was evidence of greater activity of microorganisms involved in nutrient cycling in aquaponic lettuce cultivation. The application of the microbiological consortia and minerals significantly increased the numbers and activity of the bacteria in the culture liquids 7, 14, and 21 days after inoculation. [ABSTRACT FROM AUTHOR]

Saskatoon berry has become as important as a commercial fruit crop. One main goal is to release new plant cultivars well adapted to different climatic and soil conditions. Dormant seeds obtained from breeding are serious problems delaying the program. The seeds were directly extracted from fruits after harvest (unstored) or after storage at −18 °C for 6 months (stored) and subjected to modified stratification (3 °C) with KNO3, H2O2, NO, smoke-water (SW) or scarification using sandpaper or H2SO4 for 10, 20, 30, 40 min or treatments with pulsed radio frequency (PRF) or red light. The seeds were also subjected to warm–cool stratification (20/3 °C). Unstored seeds germinated in a higher percentage and with better uniformity (T75–T25) than stored seeds. Stored seeds positively affected the onset of seed germination (T1) and mean germination time (MGT). Dormancy breakage was promoted by stratification with KNO3, SW or scarification with sandpaper, H2SO4 or treatments with PRF. The recommended method for the breeding program of breaking seeds dormancy is when unstored seeds are subjected to stratification in KNO3 (0.2%) or SW (1:100). Depending on the applied methods, the percentage of seeds' germination increased to 87% compared to untreated (64%) control seeds. The positive effects of the selected methods persisted during seedling development by stimulating their growth and enhancing the chlorophyll content index (SPAD) and effective quantum yield of PSII of chlorophyll in leaves (ΦPSII). [ABSTRACT FROM AUTHOR]

Although the application of chemical fertilizers to crops promotes plant growth and yield, their continuous use affects soil heath and creates environmental pollution. On the other hand, plant biostimulants improve nutrients absorption, plant growth, yield and produce quality and are environment-friendly. Therefore, an experiment was conducted during 2021-22 to evaluate the effect of some biostimulants on the performance of the apple cv. Anna, planted in a sandy loam soil at Marsa Matruh governorate, Egypt. Ninety trees were randomly selected and sprayed with 4 or 6% moringa leaf extract (MLE), 0.3 or 0.4% seaweed extract (SWE), 0.1% or 0.2% Fulvic acid (FA), 4% MLE + 0.3% SWE + 0.1% FA (combination 1), or 6% MLE + 0.4% SWE + 0.2% FA (combination 2) before flowering, during full bloom and one month later and compared with a control (untreated trees). The results demonstrated that spraying MLE, SWE or FA or their combinations positively improved the vegetative growth, fruit set %, fruit yield and fruit physical and chemical characteristics as well as leaf nutritional status. The positive effect of MLE, SWE and FA was increased in parallel to an increase in the used concentration of each one of them. The highest increments in the measured parameters were accompanied by the application of combination 2 over the other treatments. [ABSTRACT FROM AUTHOR]

A 2020–2021 study was performed on five-year-old guava trees to examine the influence of the foliar application of three amino acids, glycine, arginine, and glutamic acid, at a concentration of 500 or 1000 ppm. Additionally, two combinations of the three mentioned amino acids were also applied: 500 glycine + 500 arginine + 500 glutamic acid (combination 1) and 1000 glycine + 1000 arginine + 1000 glutamic acid (combination 2), and compared with a control (untreated trees). The results indicated that the application of the three amino acids, solely or in combination, was effective at increasing the shoot length, shoot diameter, and leaf chlorophyll. Additionally, the applied treatments also improved markedly the fruit set percentage, fruit yield, fruit firmness, fruit content of total soluble solids (TSS %), vitamin C (VC), and total sugars as well as the leaf mineral content (nitrogen, potassium, and phosphorus) compared with untreated trees in 2020 and 2021. Moreover, the results indicated that the combinations were more effective than individual applications and that glycine had a greater influence than arginine or glutamic acid, particularly when it was applied at 1000 ppm. [ABSTRACT FROM AUTHOR]

Different chemical attributes, measured via total soluble solids (TSS), acidity, vitamin C (VitC), total sugars (Tsugar), and reducing sugars (Rsugar), were determined for three groups of citrus fruits (i.e., orange, mandarin, and acid); each group contains two cultivars. Artificial neural network (ANN) and multiple linear regression (MLR) models were developed for TSS, acidity, VitC, Tsugar, and Rsugar from fresh citrus fruits by applying different independent variables, namely the dimensions of the fruits (length (FL) and diameter (FD)), fruit weight (FW), yield/tree, and soil electrical conductivity (EC). The results of ANN application showed that a feed-forward back-propagation network type with four input neurons (Yield/tree, FW, FL, and FD) and eight neurons in one hidden layer provided successful modeling efficiencies for TSS, acidity, VitC, Tsugar, and Rsugar. The effect of the EC variable was not significant. The hyperbolic tangent of both the hidden layer and the output layer of the developed ANN model was chosen as the activation function. Based on statistical criteria, the ANN developed in this study performed better than the MLR model in predicting the chemical attributes of fresh citrus fruits. The root mean square error of TSS, acidity, VitC, Tsugar, and Rsugar ranged from 0.064 to 0.453 and 0.068 to 0.634, respectively, for the ANN model, and 0.568 to 4.768 and 0.550 to 4.830, respectively, for the MLR model using training and testing datasets. In addition, the relative errors obtained through the ANN approach provided high model predictability and feasibility. In chemical attribute modeling, the FD and FL variables exhibited high contribution ratios, resulting in a reliable predictive model. The developed ANN model generally showed a good level of accuracy when estimating the chemical attributes of fresh citrus fruit. [ABSTRACT FROM AUTHOR]

Leaf rust is a devastating disease in wheat crop. The disease forecasting models can facilitate the economic and effective use of fungicides and assist in limiting crop yield losses. In this study, six wheat cultivars were screened against leaf rust at two locations, during three consecutive growing seasons. Subsequently, the stepwise regression analysis was employed to analyze the correlation of six epidemiological variables (minimum temperature, maximum temperature, minimum relative humidity, maximum relative humidity, rainfall and wind speed) with disease severity and yield loss (%). Disease predictive models were developed for each cultivar for final leaf rust severity and yield loss prediction. Principally, all epidemiological variables indicated a positive association with leaf rust severity and yield loss (%) except minimum relative humidity. The effectiveness of disease predictive models was estimated using coefficient of determination (R2) values for all models. Then, these predictive models were validated to forecast disease severity and yield loss at another location in Faisalabad. The R2 values of all disease predictive models for each of the tested cultivars were high, evincing that our regression models could be effectively employed to predict leaf rust disease severity and anticipated yield loss. The validation results explained 99% variability, suggesting a highly accurate prediction of the two variables (leaf rust severity and yield loss). The models developed in this research can be used by wheat farmers to forecast disease epidemics and to make disease management decisions accordingly. [ABSTRACT FROM AUTHOR]

Due to the observed climate warming, water deficiency in soil is currently one of the most important stressors limiting the size and quality of plant crops. Drought stress causes a number of morphological, physiological, and biochemical changes in plants, limiting their growth, development, and yield. Innovative methods of inducing resistance and protecting plants against stressors include the inoculation of crops with beneficial microorganisms isolated from the rhizosphere of the plant species to which they are to be applied. The aim of the present study was to evaluate 12 different strains of rhizosphere bacteria of the genera Pantoea, Bacillus, Azotobacter, and Pseudomonas by using them to inoculate strawberry plants and assessing their impact on mitigating the negative effects of drought stress. Bacterial populations were assessed by estimates of their size based on bacterial counts in the growth substrate and with bioassays for plant growth-promoting traits. The physiological condition of strawberry plants was determined based on the parameters of chlorophyll fluorescence. The usefulness of the test methods used to assess the influence of plant inoculation with rhizosphere bacteria on the response of plants growing under water deficit was also evaluated. A two-factor experiment was performed in a complete randomization design. The first experimental factor was the inoculation of plant roots with rhizosphere bacteria. The second experimental factor was the different moisture content of the growth substrate. The water potential was maintained at −10 to −15 kPa under control conditions, and at −40 to −45 kPa under the conditions of water deficit in the substrate. The tests on strawberry plants showed that the highest sensitivity to water deficiency, and thus the greatest usefulness for characterizing water stress, was demonstrated by the following indices of chlorophyll "a" fluorescence: FM, FV, FV/FM, PI, and Area. Based on the assessment of the condition of the photosynthetic apparatus and the analysis of chlorophyll "a" fluorescence indices, including hierarchical cluster analysis, the following strains of rhizosphere bacteria were found to have favorable effects on strawberry plants under water deficit: the Bacillus sp. strains DLGB2 and DKB26 and the Pantoea sp. strains DKB63, DKB70, DKB68, DKB64, and DKB65. In the tests, these strains of Bacillus sp. exhibited a common trait—the ability to produce siderophores, while those of Pantoea sp. were notable for phosphate mobilization and ACCD activity. [ABSTRACT FROM AUTHOR]

Flame Seedless grape is considered one of the most popular and favorite grapes for consumers, since it ripens early, and has good cluster quality. Flame seedless grape marketing value depends upon its desirable appearance, berry, cluster size, and shape. Therefore, it is imperative that the cluster yield and quality are enhanced to ensure profitability. In this study, the prediction of physical characteristics of clusters and berries' color attributes of Flame Seedless grape grown under different culture practices, in particular fertilization treatments, was carried out using nutritional status concentration (leaf mineral elements, total chlorophyll content, total carotenoids content) and multiple linear regression (MLR). The method was based on the development of two indices: the first is called index 1 (%) and was formulated by combing the mineral elements of N, P, K, Ca, and Mg concentrations; and the second is called index 2 (ppm) and was formulated by combing the elements of Fe, Cu, Mn, Zn, and B concentrations in leaf petioles. The results indicated that the established MLR models can obtain variation accuracy, based on values of coefficients of determination (R2) using the test set. The R2 values were in the range of 0.9286 to 0.9972 for cluster weight, cluster length, shoulder length, berries' color attributes (L*, a*, b*, chroma, hue, and color index for red grapes (CIRG)). This study highlighted that during a grown season, leaf mineral elements, total chlorophyll content, and total carotenoids coupled with a MLR model can be used successfully to evaluate the physical characteristics of the cluster and berries' color attributes of Flame seedless grape. This method is easy, fast and reliable as it retains the physical appearance of the fruits by adjusting the concentration of mineral elements, total chlorophyll content, and total carotenoids in leaves. Moreover, total chlorophyll had the greatest weight of all the predicted quality attributes. [ABSTRACT FROM AUTHOR]

A field trial was conducted to investigate the productivity of three bread wheat cultivars, namely Giza-168, Shandawel-1, and Misr-2, under different fertilization treatments, i.e., azotobacter inoculation, 25% nitrogen (N) + azotobacter, 50%N + azotobacter, 75%N + azotobacter, and 100%N of the recommended level (180 kg/ha). The treatments were laid in a split-plot design, and each was replicated three times. The findings showed that wheat cultivars examined in the two seasons exhibited significant variations (p ≤ 0.05) in plant height (PH, cm), number of tillers m−2 (NTM), number of spikelets per spike (NSS), 1000-grain weight (TGW, g), spike length (SL, cm), biological yield (BY, ton ha−1), grain yield (GY, ton ha−1), straw yield (SY, ton ha−1), harvest index (HI, %), protein content (PC, %), days to 50% heading (DTH), and chlorophyll content (CC, SPAD). As a result, Giza-168 had a higher GY (14%), HI (27%), and TGW (10%) than any of the other two cultivars in both growing seasons. Furthermore, Misr-2 exhibited the highest PH (16%), NTM (26%), NSS (28%), SL (10%), BY (30%), SY (46%), and CC (3%). The application of the two treatments of 100%N and N75% + azotobacter exhibited high and statistically similar performance, resulting in an increase in all studied traits by greater than 30–50% compared to the other three treatments. According to the findings of the current investigation, the application of N fertilizer combined with azotobacter increased wheat yield more than either solely azotobacter or N application. We concluded that the application of nitrogen combined with azotobacter reduced the quantity of applied nitrogen by 25%. [ABSTRACT FROM AUTHOR]

A two-year (2020-21) study was conducted to investigate the possibility of relying of ten-years old pear trees grown on sandy loam soil irrigated by drip on citric acid (CA), gibberellic acid (GA3) and humic acid (HA). The CA was applied at the concentrations of 500, 1000 and 1500 ppm, GA3 at 50, 100 and 150 ppm and HA at 3, 4 and 5%, whereas water spray was used as the control. The results of our study proved that CA, GA3 and HA improved the shoot length, shoot thickness, leaf area and leaf chlorophyll of pear as compared with the control. Moreover, they also positively increased the fruit set percentage and final yield of 'Le Conte' pear. The fruit weight, size and firmness were also improved under the influence of aforementioned treatments. The fruit soluble solids, total sugars, leaf nitrogen, leaf phosphorus and leaf potassium of pear were also enhanced as compared with the control. Additionally, spraying of GA3 at 150 ppm, as well as, HA at 5 and 4% were the superior treatments and showed the most significant impact on plant growth, yield, fruit quality and leaf mineral content of pear. This study provides a basis for the future elucidation of HA-, GA3- and CA-modulated molecular mechanisms in pear, which can make a significant contribution in the scientific community. [ABSTRACT FROM AUTHOR]

A two-year (2020–2021) field experiment was conducted to investigate the impact of particular nanoparticles and biofertilizers on the growth, yield, and biochemical attributes of peanuts (Cv. Giza 6). Before planting, the seeds were inoculated with two biofertilizers, mycorrhiza and phosphorine, and were considered the main plot. The subplot contained foliar sprays of nanoparticles, i.e., 200 ppm boron (B), 200 ppm calcium (Ca), their combination (Ca+B), and the control (no spray). The results revealed that mycorrhiza significantly increased 100-seed weight (70.45 g), seed yield (1.9 ton/ha), biological yield (7.5 ton/ha), crop growth rate (CGR) (2.9 g day−1 m−2), branching number (12.5), and protein content (22.96) compared with the control or phosphorine. Among the nanoparticles, Ca+B maximally improved plant height, CGR, 100-seed weight, shelling percentage, seed yield, oil content, and seed protein, while plants treated with B exhibited maximum seed nitrogen, pods per plant, and biological yield compared to other treatments. Overall, plants treated with Ca and B nanoparticles and mycorrhiza exhibited remarkable improvement in their growth, yield, and biochemical attributes, suggesting that nanotechnology and biofertilization are steps toward environmentally friendly, progressive farming. This study laid the basis for further elucidation of the molecular mechanism of plants in response to these nanoparticles and biofertilizers. [ABSTRACT FROM AUTHOR]

The main goal of this work was to study the structural transformation of humic acids (HAs) under the influence of selected strains of fungi (Aspergillus niger and Paecilomyces lilacinus) and bacteria (Bacillus sp., Paenibacillus polymyxa and Bacillus amyloliquefaciens) with/without the presence of NPK fertilizers. Two-year experiments were conducted on two different soils and HAs isolated from these soils were examined for structure, humification degree, and quantity using fluorescence and UV-Vis spectroscopy, elemental analysis, and extraction methods. Results showed that the applied additives contributed to the beneficial transformation of HAs, but effects differed for various soils. HAs from silty soil with higher organic carbon content showed simplification of their structure, and decreases in humification, molecular weight, and aromaticity under the influence of fungi and bacteria without NPK, and with NPK alone. With both fungi and NPK, increases in O/H and O/C atomic ratios indicated an increase in the number of O-containing functional groups. HAs from sandy soil did not show as many significant changes as did those from silty soil. Sandy soil exhibited a strong decline in HA content in the second year that was reduced/neutralized by the presence of fungi, bacteria, and NPK. Periodically observed fluorescence at ~300 nm/450 nm reflected formation of low-molecular HAs originating from the activity of microorganisms. [ABSTRACT FROM AUTHOR]

The application of plant beneficial microorganisms has been widely accepted as an efficient alternative to chemical fertilizers and pesticides. Isolation and selection of efficient microorganisms, their characterization and testing in soil-plant systems are well studied. However, the production stage and formulation of the final products are not in the focus of the research, which affects the achievement of stable and consistent results in the field. Recent analysis of the field of plant beneficial microorganisms suggests a more integrated view on soil inoculants with a special emphasis on the inoculant production process, including fermentation, formulation, processes, and additives. This mini-review describes the different groups of fermentation processes and their characteristics, bearing in mind different factors, both nutritional and operational, which affect the biomass/spores yield and microbial metabolite activity. The characteristics of the final products of fermentation process optimization strategies determine further steps of development of the microbial inoculants. Submerged liquid and solid-state fermentation processes, fed-batch operations, immobilized cell systems, and production of arbuscular mycorrhiza are presented and their advantages and disadvantages are discussed. Recommendations for further development of the fermentation strategies for biofertilizer production are also considered. [ABSTRACT FROM AUTHOR]

Regarding the unfavourable changes in agroecosystems resulting from the excessive application of mineral fertilizers, biopreparations containing live microorganisms are gaining increasing attention. We assumed that the application of phosphorus mineral fertilizer enriched with strains of beneficial microorganisms contribute to favourable changes in enzymatic activity and in the genetic and functional diversity of microbial populations inhabiting degraded soils. Therefore, in field experiments conditions, the effects of phosphorus fertilizer enriched with bacterial strains on the status of soil microbiome in two chemically degraded soil types (Brunic Arenosol—BA and Abruptic Luvisol—AL) were investigated. The field experiments included treatments with an optimal dose of phosphorus fertilizer (without microorganisms—FC), optimal dose of phosphorus fertilizer enriched with microorganisms including Paenibacillus polymyxa strain CHT114AB, Bacillus amyloliquefaciens strain AF75BB and Bacillus sp. strain CZP4/4 (FA100) and a dose of phosphorus fertilizer reduced by 40% and enriched with the above-mentioned bacteria (FA60). The analyzes performed included: the determination of the activity of the soil enzymes (protease, urease, acid phosphomonoesterase, β-glucosidase), the assessment of the functional diversity of microorganisms with the application of BIOLOGTM plates and the characterization of the genetic diversity of bacteria, archaea and fungi with multiplex terminal restriction fragment length polymorphism and next generation sequencing. The obtained results indicated that the application of phosphorus fertilizer enriched with microorganisms improved enzymatic activity, and the genetic and functional diversity of the soil microbial communities, however these effects were dependent on the soil type. [ABSTRACT FROM AUTHOR]

We tested agriculturally and chemically degraded Brunic Arenosol and Abruptic Luvisol of contrasting textures to establish the early response of soil quality to two different mineral fertilizers (Polifoska and urea) amended with microbes applied in optimal and reduced doses. The soil samples were collected from two fields under maize: one week (Ist sampling time) and six months (IInd sampling time) after fertilization. The laboratory experiment included determination of: catalase activity, dehydrogenase activity, microbial biomass, and basal respiration; pH and dissolved organic carbon (DOC) were also measured. The silty Luvisol was characterized by higher biological activity than the sandy Arenosol. Biofertilizer addition to degraded soils increased the biological activity, even in reduced doses of additives used; however the responses of the tested microbiological indicators were different. Soil texture affected the positive biomass response to biofertilizers which was observed in samples from Ist sampling time in silty soil, while from IInd sampling time in sandy soil. Based on our results, we propose that Polifoska with microorganisms (used in full dose) may be optimal for silty soil. Polifoska (in reduced dose) and urea (both in full and reduced dose) may be recommended for sandy soils. Increasing pH was a stronger driver of soil biological activity than DOC. Long-term field testing is suggested for validating our results. [ABSTRACT FROM AUTHOR]