Interaction of 2-Hydroxyquinoxaline (2-HQ) on Soil Enzymes and Its Degradation: A Review

Venkata Subba Reddy Gangireddygari,Rajasekhar Reddy Bontha,Ju-Yeon Yoon 인간식물환경학회 2020 인간식물환경학회지 Vol.23 No.4

The United Nations project the world population to reach 10 billion by the year 2057. To increase the food of the ever-increasing world population, agrochemicals are indispensable tools to the boon in agriculture production. These agrochemicals are a serious threat to the health of humans, plants, and animals. Agrochemicals are ultimately reached to the main reservoir/sink such as soil and contaminating the groundwater, disturb the soil health and in turn a serious threat to biogeochemical cycling and the entire biosphere. Among agrochemicals, quinalphosis one of the most repeatedly and widely used insecticides in the control of a wide range of pests that attack various crops. Quinalphos is shown to be primarily toxic in organisms by acetylcholinesterase enzyme action. Hydrolysis of quinalphos produces amajor metabolite 2-hydroxyquinoxaline (2-HQ), which has shown secondary toxicity in organisms. 2-HQ is reported to be mutagenic, carcinogenic, growth inhibition and induce oxidative stress in organisms. Quinoline is a heterocyclic compound and structural resemblance of 2-HQ with minor changes, but its degradation studies are enormous compared to the 2-HQ compound. Biotic factors in fate and behavior of 2-HQ in the environment are least studied. 2-HQ interactions with soil enzymes are vary from soil to soil. Based on the toxicity of 2-HQ in our stockpile we need to isolate a handful of microorganisms to treat this persistent metabolite and also other metabolites/compounds.This brief review will be significant from the point of biological and environmental safety.

Inhibitory Effect of Chitosan and Phosphate Cross-linked Chitosan against Cucumber Mosaic Virus and Pepper Mild Mottle Virus

Venkata Subba Reddy Gangireddygari,Bong Nam Chung,In-Sook Cho,Ju-Yeon Yoon 한국식물병리학회 2021 Plant Pathology Journal Vol.37 No.6

Cucumber mosaic virus (CMV) and Pepper mild mot- tle virus (PMMoV) causes severe economic loss in crop productivity of both agriculture and horticulture crops in Korea. The previous surveys showed that naturally available biopolymer material – chitosan (CS), which is from shrimp cells, reduced CMV accumulation on pepper. To improve the antiviral activity of CS, it was synthesized to form phosphate cross-linked chitosan (PCS) and compared with the original CS. Initially, the activity of CS and PCS (0.01%, 0.05%, and 0.1% con- centration) compound against PMMoV infection and replication was tested using a half-leaf assay on Nico- tiana glutinosa leaves. The total number of local lesions represented on a leaf of N. glutinosa were counted and analyzed with phosphate buffer treated leaves as a neg- ative control. The leaves treated with a 0.1% concentra- tion of CS or PCS compounds exhibited an inhibition effect by 40-75% compared with the control leaves. The same treatment significantly reduced about 40% CMV accumulation measured by double antibody sandwich enzyme-linked immunosorbent assay and increased the relative expression levels of the NPR1, PR-1, cysteine protease inhibitor gene, LOX, PAL, SRC2, CRF3 and ERF4 genes analyzed by quantitative reverse transcrip- tase-polymerase chain reaction, in chili pepper plants.

Inhibitory Activity of Pseudomonas putida and Bacillus licheniformis Supernatants on PMMoV in Chili Pepper

Venkata Subba Reddy Gangireddygari,조인숙,최세나,윤주연 인간식물환경학회 2023 인간식물환경학회지 Vol.26 No.1

Background and objective: Plant viruses are major obstacles to enhancing crop productivity in both agriculture and horticulture throughout the world, resulting in losses of several billion dollars every year. Controlling viruses is arduous, so agrochemicals are widespread. To minimize the usage of those, this study's objective was to assess bacterial cultures supernatants on pepper mild mottle virus (PMMoV) in chili pepper plants and identify its secondary metabolites. Methods: This 48-h grown Pseudomonas putida (PP) and Bacillus licheniformis (BL) cultures supernatants were foliar sprayed separately in chili pepper plants 24-h before PMMoV inoculation (T1), and 24-h before and after PMMoV inoculation (T2), 2wpi (week's post inoculation), the virus titer was determined by using a double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), and the supernatants were extracted with ethyl acetate and concentrated by rota-evaporation before being analyzed in gas chromatography mass spectrometry (GC-MS). Results: The culture supernatants of PP and BL inhibit PMMoV by 43-47% in both the treatments (T1 & T2) compared to the control. The GC-MS chromatogram of two cultures of supernatants identified the molecules of cyclo (Pro-Val), cyclo (Pro-Leu), and cyclo (Phe-Pro). Commercial forms of these three molecules at three concentrations showed a hypersensitive response, ranging from 45-65% for PMMoV in Nicotiana glutinosa. Conclusion: The results revealed that supernatants of PP and BL-containing compounds have biological control of PMMoV in chili pepper plants.

Inhibitory Effects of Pepper Mild Mottle Virus Infection by Supernatants of Five Bacterial Cultures in Capsicum annuum L.

Venkata Subba Reddy Gangireddygari(Venkata Subba Reddy Gangireddygari ),In-Sook Cho(In-Sook Cho),Sena Choi(Sena Choi),Ju-Yeon Yoon(Ju-Yeon Yoon) 한국식물병리학회 2022 Plant Pathology Journal Vol.38 No.6

Pepper mild mottle virus (PMMoV), one of the most prevalent viruses in chili pepper (Capsicum annuum L.) is a non-enveloped, rod-shaped, single-stranded positive-sense RNA virus classified in the genus Tobamovirus. The supernatants of five bacterial cultures (Pseudomonas putida [PP], Bacillus licheniformis [BLI], P. fluorescens [PF], Serratia marcescens [SER], and B. amyloliquifaciens [BA]) were analyzed to find novel antiviral agents to PMMoV in chili pepper. Foliar spraying with supernatants (1:1, v/v) obtained from Luria-Bertani broth cultures of PP, BLI, PF, SER, and BA inhibited PMMoV infection of chili pepper if applied before the PMMoV inoculation. Double-antibody sandwich enzyme-linked immunosorbent assay showed that treatments of five supernatants resulted in 51-66% reductions in PMMoV accumulation in the treated chili pepper. To identify key compounds in supernatants of PP, BLI, PF, SER, and BA, the supernatants were subjected to gas chromatography-mass spectrometry. The 24 different types of compounds were identified from the supernatants of PP, BLI, PF, SER, and BA. The compounds vary from supernatants of one bacterial culture to another which includes simple compounds— alkanes, ketones, alcohols, and an aromatic ring containing compounds. The compounds triggered the inhibitory effect on PMMoV propagation in chili pepper plants. In conclusion, the cultures could be used to further conduct tissue culture and field trial experiments as potential bio-control agents.

시설재배 국화에서 총채벌레의 종 동정 및 보독 바이러스 동시 검출을 위한 다중 진단법 적용

윤주연(Ju-Yeon Yoon),윤정범(Jung-Beom Yoon),서미혜(Mi-Hye Seo),최승국(Seung-Kook Choi),조인숙(In-Sook Cho),정봉남(Bong-Nam Chung),양창열(Chang Yeol Yang),Venkata Subba Reddy Gangireddygari 한국식물병리학회 2020 식물병연구 Vol.26 No.4

이번 연구는 국화에서 문제되는 총채벌레의 종 동정 및 보독 바이러스인 토마토반점위조바이러스(Tomato spotted wilt virus, TSWV)를 동시에 확인할 수 있는 진단방법을 개발하였다. 이는 총채벌레 1마리에서 추출한 핵산에 꽃노랑총채벌레및 대만총채벌레의 ITS2 부분에 특이적인 프라이머와 TSWV 외피단백질(N) 유전자 특이적인 프라이머를 동시에 넣어 reverse tran scription‒polymerase chain reaction을 수행하여 DNA를증폭시키는 방법으로 전기영동하여 각각 287, 367, 777 bp의DNA 단편의 크기를 비교함으로써 총채벌레의 종 동정 및 총채벌레의 TSWV 보독 여부를 동시에 확인할 수 있다. 충청남도 태안 및 경상남도 창원의 국화 시설하우스에서 총채벌레를 포집하여 총채벌레 우점종과 총채벌레의 TSWV 보독율을 조사한결과, 태안의 국화 시설하우스에서는 꽃노랑총채벌레가 83.7% 로 우점하고 있으며 채집된 총채벌레 중 72.9%가 TSWV를 보독하고 있었으며, 창원에서는 꽃노랑총채벌레가 92.2%를 차지하고 있으며 84.0%의 총채벌레에서 TSWV가 진단되었다. 이러한결과는 Frankliniella occidentalis가 우점종이며 온실의 국화 식물에서 TSWV의 전반에 중요한 역할을 한다는 것을 확인해준다. 이번 연구는 국화 시설하우스에서 총채벌레를 통한 TSWV 의 시설하우스내 유입시기 및 확산 경로 등 바이러스의 역학연구를 위한 간편진단법으로 활용 가능함을 예시해준다. We have developed a simultaneous diagnostic method that can identify both the species of thrips and tomato spotted wilt virus (TSWV) that are problematic in chrysanthemum plants. This is a method of amplifying DNA by performing reverse transcription-polymerase chain reaction by simultaneously adding primers specific to TSWV coat protein (N) gene and primers specific to the internal transcribed spacer 2 region of Frankliniella occidentalis and F. intonsa using total nucleic acid extracted from one thrips. The sizes of DNA fragments for TSWV, F. occidentalis, and F. intonsa were 777, 287, and 367 bp, respectively. These results showed species identification of thrips and whether thrips carrying TSWV can be simultaneously confirmed. Further usefulness of the simultaneous diagnostic method was made from greenhouse survey at chrysanthemum greenhouses in Taean (Chungcheongnam-do) and Changwon (Gyeongsangnam-do) to investigate the identification of thrips species and the rate of thrips carrying TSWV. Of thrips collected from the greenhouses, 83.7% thrips was F. occidentalis and 72.9% F. occidentalis carried TSWV in Taean. Similarly, the diagnostic method showed that 92.2% thrips was F. occidentalis and 84.0% F. occidentalis carried TSWV in Changwon. These results confirm that F. occidentalis is a dominant thrips species and the thrips species plays a crucial role in the transmission of TSWV in chrysanthemum plants in the greenhouses. Taken together, this study showed a simple diagnostic method for thrips identification and epidemiological studies of the timing and spread of TSWV through thrips in chrysanthemum greenhouses in South Korea.