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Organic fertilizers may contribute substantially to improving yield, soil quality, and reducing the environmental impacts of conventional farming. This study investigates the effects of organic fertilizers, like green manure composed of hairy vetch (HV), livestock compost (LC), or a combination of the two (LC + HV), has on red pepper growth, yield, fruit quality, and soil microbial populations as compared to more commonly used chemical fertilizers. This study investigates the effects of different fertilizer treatments on red pepper growth, yield, quality, and soil microbial populations. The experimental plot treatments were no fertilizer (CON), chemical fertilizer, HV, LC and LC + HV. In these treatments, 70-day-old red pepper plants were grown for an additional 140 days under treatment conditions. Plant dry weight, macro- and micro-nutrient contents were analyzed. Post-harvest soil properties and cultivable soil microbial population were determined. HV and LC + HV treatments had significantly high leaf and stem dry weight. All the treatments increased T–N, P and Mg contents in plants and the highest uptake was recorded for plants fertilized with HV. After harvest, soil fertilized with LC + HV had higher soil organic matter and available P, K and Ca as compared to chemical fertilizers. In addition, soil fertilized with organic fertilizers had significantly more cultivable microbial populations than chemical fertilizers. Overall, these results suggest that organic fertilizers could be used to reduce the application of synthetic fertilizers and aiding sustainable agriculture.

Arbuscular mycorrhizal fungi (AMF) are well-known for their ability to improve plant growth and help plants withstand abiotic stress conditions. Unlike other fungi and bacteria, AMF cannot be stored, as they are obligate biotrophs. Long-term preservation of AMF spores is challenging and may lead to the loss of viability and efficiency. This study aimed to understand the effect of prolonged subculture of AMF species on the growth and glomalin-related soil protein (GRSP) from red pepper (Capsicum annuum L.). AMF spores were mass-produced using different techniques and subcultured in pots with sorghum sudangrass as the host plant for 3 years. Experimental soil samples were collected from natural grassland. Five different AMF inocula were used in triplicate as treatments. After 70 days of growth, red pepper plants were harvested and plant dry weight, plant nutrient content, mycorrhizal colonization, AMF spore count, and soil glomalin content were determined. AMF-treated plants displayed higher dry weight than controls, with only fruit dry weight being significantly different. Similarly, significant differences in phosphorous and potassium contents of the above-ground plant parts were observed between mycorrhizal and control treatments. In addition, soil GRSP content was significantly higher in plants inoculated with Rhizophagus sp. and Gigaspora margarita. The increased plant growth and GRSP content suggest that AMF can be maintained for 3 years without losing their efficiency if subcultured regularly with different symbiotic host plants.

BACKGROUND: The use of green manure and compost as organic fertilizer may increase crop yield and soil fertility due to improved soil nutrient availability and soil organic matter content (SOM). This study aimed to investigate the effects of hairy vetch (Vicia villosa L.) and compost application on red pepper growth, yield, fruit quality and soil health. METHODS AND RESULTS: The treatments were no fertilizer (CON), chemical fertilizer (CF), hairy vetch (HV), and livestock compost+HV (LC+HV). Red pepper seedlings (70 days old) were transplanted and maintained in experimental plots for 140 days. Plant dry weight, microand macronutrient contents of plants and soil chemical properties were determined. All fertilizer treatments significantly increased plant dry weight. Fruit yield was significantly highest with HV treatment. As for nutrient content, plants in HV and LC+HV treatments have significantly higher K and Ca contents than the other treatments. Regarding soil properties, HV and LC+HV application significantly altered the soil chemical properties. Significantly higher SOM was observed in HV and LC+HV treated soils. CONCLUSION: The results of this study suggest that short-term application of hairy vetch and compost is an effective alternative to the conventional chemical fertilizer to increase fruit yield red pepper and improve soil health.

The fruits of Citrus unshiu are one of the most popular and most enjoyed fruits in Korea. As we continue to seek for bioactive metabolites from Korean natural resources, our study on the chemical constituents of the fruits of C. unshiu resulted in the isolation of a new flavonoid glycoside, limocitrunshin 1, along with seven other flavonoids 2-8 and a limonoid 9. All structures were identified by spectroscopic methods, namely 1D and 2D NMR, including HSQC, HMBC, and (1)H-(1)H COSY experiments, HRMS, and other chemical methods. Compounds 3, 5, and 9 are reported to be isolated from this fruit for the first time. The isolated compounds were applied to activity tests to verify their inhibitory effects on inflammation and nephrotoxicity. Compounds 6 and 9 showed the most potent inhibitory activity on renal cell damage and nitric oxide production, respectively. Thus, the fruits of C. unshiu could serve as a valuable natural source of bioactive components with health benefits for potential application in functional foods.

Owing to the effect of symbiotic gut bacteria on the proliferation of infectious disease-transferring insects and their potential as paratransgenic tools, their identification or securing their use in controlling insect vectors is urgently needed. Bradysia agrestis is one of the major plant epidemic vectors in East Asia; however, its normal microbiota remains unstudied. This research was primarily designed to secure promising candidates for use in a paratransgenic approach to phytopathogen control, as well as to provide a picture of the gut microbiota of wild-caught B. agrestis from a blight field. A total of 180 larvae from three different regions in South Korea were analyzed for their gut microfloral composition. Diverse bacterial strains were purely isolated based on morphological differences in microbiological media. We found a total of 64 bacterial strains in the B. agrestis midgut and analyzed their 16S rRNA gene sequences for molecular identification and phylogenetic characterization. Furthermore, the microbial diversity of each normal microbiota group was analyzed with various diversity indices. Bacterial biota including species diversity, richness or species distribution, species constituents, and dominance varied by each regional vector group. The most widely distributed species was Bacillus aryabhattai, and the most common genera were Bacillus and Microbacterium. These saprophytic bacteria were isolated from all regional groups and their potential as paratransgenic candidates for controlling B. agrestis-mediated plant disease is discussed.

This study was carried out to determine the effect of mixing with paraffin oil on rainfastness of mancozeb on citrus fruits and assay the improvement of control effect of mancozeb against citrus melanose by mixing with paraffin oil. In artificial rainfall condition (7.2 mm/hr), the attached contents of mancozeb on detached fruits were the most in treatment of mancozeb 0.2% + paraffin oil 0.1% as the contents was 7.43 μg/cm2 after treatment of rainfall for 10 hr. In open field condition, the contents of attached mancozeb on fruits were significantly more in treatment of mancozeb 0.2% + paraffin oil 0.1% or 0.25% than the other treatments 1, 15 and 25 days after treatment 2009 and 2010 seasons. The disease incidence was significantly lower in treatment of mancozeb 0.2% + paraffin oil 0.1% or 0.25% than treatment of mancozeb 0.2% only 2009, 2010 and 2011 seasons. Based on this study, it was suggested that the control effect of mancozeb against citrus melanose can be improved by mixing with paraffin oil.

The percent of diseased fruit by Diaporthe citri was the most 16.8% in 2010 and the least 3.8% in 2005, and the average was 8.8% from 2003 to 2012. The degrees of disease incidence were relatively high, 17.0, 22.6, 19.2 and 18.9%, in 2003, 2004, 2007 and 2010, respectively. The percent of diseased fruit by Elsinoe fawcettii was the most 0.72% in 2004, and then gradually decreased to 0.08% in 2008, and the average was from 0.28% from 2004 to 2011. In case of canker by Xanthomonas citri subsp. citri, the percent of diseased fruit was the most 2.19% in 2004, and gradually decreased to 0.08 and 0.10% in 2009 and 2010, respectively. The average was 0.81% from 2004 to 2012. The melanose by D. citri was most in south-east area of Jeju Island, and east and west in case of canker. The melanose symptoms were initially appeared from mid June, mainly peaked late of July to late August. The canker symptoms were initially produced on leaves of natsudaidai and grapefruit cultivated in open field middle of June in 2010 and 2011 and late of May in 2012. The scab disease was firstly appeared approx. early or mid May and then rapidly increased late of May to middle of June. The inoculum was mainly produced from dead twigs late June to early of August.

Scirtothrips Dorsalis (Thysanoptera: Thripidae) recently has been recognized as a major source of the pest damage in the citrus fruit orchards. So its arrival has been predicted periodically but it is difficult to identify adults of the pest with the naked eyes because of their size smaller than the 0.8mm. In this paper, we propose a method to detect candidate areas for automatic identification of Scirtothrips Dorsalis on forecasting traps. The proposed method uses a histogram-based template matching where the composite image synthesized with the gray-scale image and the gradient image is used. In our experiments, images are acquired by the optical microscopy with 50 magnifications. To show the usefulness of the proposed method, it is compared with the method we previously suggested. Also, the performances when the proposed method is applied to noise-reduced images and gradient images are examined. The experimental results show that the proposed method is approximately 14.42% better than our previous method, 41.63% higher than the case that the noise-reduced image is used, and 21.17% higher than the case that the gradient image is used.

It has been known that streptomycin resistance in bacteria can occur as a results of chromosomal mutation or through gene acquisition or both. Chromosomal mutations for resistances are point mutations in the rpsL gene, which alter ribosomal protein S12. Acquired resistance has occurred when an SmR plasmid carrying transposon Tn5393 with tandem strA-strB gene is transferred by conjugation. A total of 686 isolates of Xanthomonas smithii subsp. citri causal agent of citrus canker disease were collected from 26 citrus orchards in Jeju Island in 2003 and 2004 seasons. Forty-nine of 111 isolates from streptomycin non-sprayed orchards in 2003 season were resistant to streptomycin. Of 107 isolates from orchards sprayed one time with streptomycin, 58 isolates were resistant, and 166 of 221 isolates from orchards sprayed two times with streptomycin were resistant. In 12 orchards sprayed three or more times with streptomycin, 219 of 247 isolates were resistant to streptomycin. Twenty-five isolates of X. smithii subsp. citri were surveyed to identify the mechanisms of streptomycin resistance in this study. Twenty-one of these 25 isolates were resistant to streptomycin, and it was proven by PCR assay that 18 of the 21 streptomycin resistant isolates have the strB gene. In sixteen of the 21 streptomycin resistant isolates, it was occurred a point mutation altered codon lysine (AAG)-41 of rpsL gene to arginine (AGG). The streptomycin-sensitive isolates easily acquired the resistance by mixed culture with resistant isolates. The strB gene was amplified from the isolates that acquired the resistance by mixed culture, and one isolate of them was also point-mutated in codon 41 of rpsL gene to be resistant. In this study, most of the streptomycin-resistant isolates of X. smithii sub sp. citri in Jeju island expressed the resistance by both chromosomal point mutation and gene acquisition, and the resistance was easily acquired through conjugation by culture mixed with streptomycin resistant and sensitive strains.

Silver-grey or dark brown scaring, or dark brown discolored damages caused by the yellow tea thrip, Hood (Thysanoptera: Thripidae) have occurred on citrus fruits cultivated in the open field in east-south area orchards of Jeju Island since 2007. The weekly population of yellow tea thrips adults caught with a yellow sticky trap increased gradually from early May and peaked in late August, 2009. In 2010 and 2011, the most population was in early October. The yellow tea thrips of some species usually dominated from July in open citrus fields, and seven generations, at least, had occurred from May to late October 2009 by a yellow sticky trap survey. In 2009, larva were observed from July and with peaks from late August to mid September and early October on citrus fruits. The damage symptoms appeared in the mid September. In 2011, the population peaks were in early July and late September, and the symptoms increased continually from mid July to late October. The symptoms were silver-scars or initial dark discolorations and then gradually changed to dark-brown discolorations or dark-brown scars. The percent of damaged fruits were 0.9%, 0.4%, 0.8% and 2.7% in 2008, 2009, 2010 and 2011, respectively, by survey in 64 typical orchards in Jeju Island. We are the first to report symptoms of the yellow tea thrip ( ) on citrus fruits.

Ethnopharmacological relevance Citrus unshiu (Rutaceae) is an easy-peeling citrus fruit, which has been used as a traditional Korean medicine for improving skin elasticity, relieving fatigue and cough, and preventing bronchitis, flu, and various cancers. However, its active components associated with anti-inflammation and underlying mechanisms remain unknown. In this study, we investigated the active constituents from the fruits of Citrus unshiu and evaluated the anti-inflammatory activity in order to support the traditional usage of Citrus unshiu. Material and methods Repeated column chromatography, together with a semi-preparative HPLC purification was used to separate the bioactive constituent from the EtOAc soluble fraction of the EtOH extract of Citrus unshiu fruits. Anti-inflammatory effects of the isolated compounds on lipopolysaccharide (LPS)-induced production of pro-inflammatory mediators were examined using RAW264.7 macrophage cells. Results A new cyclic peptide, citrusin XI (1), was isolated and identified from the fruits of Citrus unshiu. The structure of compound 1 was elucidated by spectroscopic analysis, including 1D and 2D nuclear magnetic resonance (NMR) (1H, 13C, COSY, HMQC and HMBC experiments), and high resolution (HR)-mass spectrometry, and its absolute configurations were further confirmed by the Marfey׳s method. Compound 1 decreased NO production in LPS-stimulated RAW264.7 cells in a dose-dependent manner with an IC50 value of 70 μM. Compound 1 suppressed NO production by decreasing iNOS expression but COX-2 expression was slightly associated with the reduction by compound 1 in LPS-induced RAW264.7 cells. Furthermore, compound 1 inhibited NF-κB activation by blocking IκBα degradation and NF-κB phosphorylation in LPS-stimulated RAW264.7 cells. Conclusions These results indicate that a new cyclic peptide, citrusin XI, from Citrus unshiu fruits has anti-inflammatory properties that inhibit the release of pro-inflammatory mediators. Compound 1 decreases NO production by decreasing iNOS expression and NF-κB activation associated with IκBα degradation and NF-κB phosphorylation in LPS-induced RAW264.7 cells. This is the first study to clarify the underlying mechanism of the anti-inflammatory effect exerted by a pure isolated compound from Citrus unshiu in LPS-stimulated RAW264.7 macrophage cells. The phytochemical, citrusin XI of Citrus unshiu may serve as lead compound in the design of new agents for preventing and treating inflammatory diseases.