INTERNATIONAL BIOHERBICIDE GROUP

IBG NEWS December 2014 ________________________________________________________________ TABLE OF CONTENTS Contact Addresses ........................................................................1 Chairman's Comments ..................................................................2 XII IBG Workshop ..........................................................................5 IBG Website and Mailing List.........................................................5 People & Places ............................................................................5 Bioherbicide Research...................................................................6 Upcoming Meetings of Interest ....................................................16 Recent Publications & Presentations...........................................16 Editor's Corner .............................................................................18 CHAIR Karen Bailey Agriculture & Agri-Food Canada, 107 Science Place, Saskatoon, Saskatchewan, S7N 0X2, CANADA Phone: +306.9567260; Fax: +306.9567247; e-mail: Karen.Bailey@agr.gc.ca VICE CHAIR Graeme Bourdôt AgResearch Lincoln, Cnr Springs Road & Gerald Street, PB 4749, Christchurch 8140, NEW ZEALAND Phone: +64.3.9833973; Fax : +64.3.9833946; e-mail: graeme.bourdot@agresearch.co.nz NEWSLETTER EDITOR Maurizio Vurro Institute of Sciences of Food Production - C.N.R. – Via Amendola 122/O - 70125 - Bari - ITALY Phone: +39.0805929331; Fax: +39.0805929374; e-mail: maurizio.vurro@ispa.cnr.it

CHAIRMAN’S COMMENTS Another year has gone by quickly since the last IBG Workshop. It is time for us to catch up on what is new in the bioherbicide field. Our Most Recent IBG Meeting, August 2013 Certainly the XI th IBG Workshop was a great success. It was held for two days in Nanjing, China on August 22-24, 2013, just prior to the International Congress of Plant Pathology in Beijing. Dr. Qiang Sheng from the Nanjing Agricultural University graciously hosted a total of 121 participants from the United States, Canada, Australia, New Zealand, Turkey, Costa Rica and China. Under the background of global environmental change and the continued input of agrochemicals, the meeting explored the development of bioherbicides that will provide an alternative agro-product supporting sustainable agriculture. The specific topics included in this workshop were: 1) Progress and prospects of bioherbicides, 2) Screening and biological study of bioherbicides, and 3) Commercialization and registration of bioherbicides. More than 32 papers and abstracts, 17 oral presentations and eight posters were enthusiastically contributed. The participants also visited Weed Research Laboratory, Nanjing Agricultural University (NAU) and Bioherbicide Field Demonstration trials (Jiangpu Farm). This was our largest IBG meeting to date and it reflected our traditions of maintaining a high academic standard with a convivial, scientific atmosphere. On behalf of all IBG members, I congratulate Dr Sheng and his team members, Dr. Xiaoling Song, Dr. Weimin Dai, and Ms. Jing Kuan, on hosting a successful meeting.

Group photograph of the XI IBG, Nanjing, China

Dr. Qiang Sheng addressing the meeting participants

Field trip

Banquet entertainment

Our Next IBG Meeting, June 2016 During the past year, I have made contact with the organizers of the IWSS and identified an opportunity for IBG to meet with that group in Prague in June 2016. IBG will be incorporated as an event within the larger meeting which will help to boost our attendance. Maurizio Vurro has agreed to be the IBG Local Contact for the meeting organization. I submitted an article about IBG to the IWSS newsletter so that their members become aware of our interests. We need help to raise sponsorship for this meeting, develop ideas for sessions and speakers, and plan a social event. If anyone would like to volunteer to help with the organization of the next meeting, please step forward and contact Maurizio or myself. Passing the IBG Torch It has come time for me to step down as Chairperson of IBG. I retired from Agriculture & Agri-Food Canada in June, 2014. Although I am still around to the end of next year to finish my projects and write papers, my interests are diversifying as I transition away from full time research. IBG needs a chairperson who is able to remain current in this field. The job is not hard, nor is it time consuming. You write a short note to the newsletter once or twice in a year, determine a place to hold a meeting once every two years and a local person who can co-ordinate the logistics. That is it; Easy peasy! To apply for the job, just send me an email expressing interest or to apply on behalf of someone else who you think would make a good Chairperson send me their name, so I may talk to them. Conveying Gratitude Once again, I want to express appreciation on behalf of IBG members to Maurizio for his efforts and energy in maintaining our website and producing the newsletter. We are a small volunteer organization and are heavily dependent on the good will and spirit of our membership in order to continue. Thanks to all who have contributed to IBG this year. Karen Bailey, Chairperson of IBG - Karen.Bailey@agr.gc.ca

XII IBG Workshop - Prague, Czech Republic 2016

IBG WEBSITE AND MAILING LIST In the next few weeks the IBG Website (http://ibg.ba.cnr.it) will be completely reorganized, updated and renewed by myself using WORDPRESS, an open source system to manage websites. You will be informed when it will be ready, in order to have your comments and suggestions. I will try to add some attractive and useful tools (blog, links to social networks, forms for enquiries, visitor counters, etc.). Currently, the IBG mailing list contains 296 addresses. I believe that several of them are addresses no more valid, or even e-mail addresses owned by people not more interested in the subject. In order to have a clearer picture of the situation, in the near future I will send a personal e-mail to each of the addresses to test its validity. Maurizio Vurro [maurizio.vurro@ispa.cnr.it]

PEOPLE & PLACES Saskatoon Research Centre, Agriculture & Agri-Food Canada Drs. Karen Bailey, Susan Boyetchko, Michelle Hubbard, Russell Hynes New Funding Russ Hynes and Karen Bailey received a two year grant from the Western Grains Research Foundation to collect data for an agricultural regulatory submission to use Phoma macrostoma to control dandelion, Canada thistle, wild mustard, and other broadleaved weeds on wheat, barley, kamut, and other grains as well as flax, and alfalfa. They will collect data on crop tolerance, weed efficacy and dose, and determine the environmental factors that promote or limit efficacy under field conditions. Dr. Sue Boyetchko - Grass Weed Bioherbicide:

IBG is partnering with the

7th International Weed Science Congress

at the Clarion Hotel in Prague, June 19-25, 2016

http://www.iwss.info/iwsc.php

1) The full genomic sequencing data for Pseudomonas fluorescens BRG100 has been determined and it has been accepted by GenBank. This information is being used to generate DNA strain-specific markers for environmental fate testing. This work was conducted in collaboration with Dr. Tim Dumonceaux (AAFC, Saskatoon).

2) A paper on the economics of the Pseudomonas fluroescens BRG100 as a bioherbicide for grass weed control was published in the journal Bioresource Technology, titled " Technoeconomic analysis of large scale production of pre-emergent Pseudomonas fluorscens microbial bioherbice in Canada". This paper outlines the economics of commercializing BRG100 as a stand-alone product and the capital investment involved. Authors: Edmund Mupondwa, Xue Li, Susan Boyetchko, Russ Hynes, and Jon Geissler

3) We are continuing our formulation research with BRG100 through a collaboration with a company who will be testing and developing novel granular formulation for application into bioherbicides. This company has expertise in inoculants and microbial biopesticides in Canada and Europe and is continuing its investment in biological R&D.

4) We have been testing a number of our bacterial strains for control against wooly cupgrass, a highly invasive grass weed in eastern Canada (in collaboration with Marie Josée Simard. AAFC, St. Jean sur Richelieu). We selected bacterial strains with broad spectrum activity against several grass weeds and early indications are that some of our bacteria can cause significant reductions in germination and/or root growth of the weed.

Dr. Russ Hynes spent the month of October at Nanjing Agricultural University, Nanjing China collaborating with Dr. Sheng Qiang, staff and students of the Weed Research Laboratory on formulation development and strategic application techniques for bioherbicide Curvularia eragrostidis. Russell Hynes [Russell.Hynes@AGR.GC.CA]

BIOHERBICIDE RESEARCH A Historic First: Registration of a Bioherbicide Containing a Plant Virus as the Active Ingredient A Report and Commentary by R. Charudattan, Emeritus Professor, Plant Pathology Department, University of Florida-Institute of Food and Agricultural Sciences, Gainesville; rcharu@ufl.edu On December 12, 2014 the U.S. Environmental Protection Agency granted FIFRA Section 3 registration for SolviNix® LC, a bioherbicide containing Tobacco mild green mosaic virus strain U2 (TMGMV U2) as the active ingredient. The registration permits the bioherbicide to be sold and used as a post-emergent foliar herbicide to control Solanum viarum (common name: tropical soda apple) in the United States. It is the first time a plant virus has been registered as an herbicide active ingredient anywhere in the world. The registration brings to fruition a highly interesting and unique bioherbicide project that started in 2000 in Dr. Charudattan’s biological control of weeds program at the University of Florida-Institute of Food and Agricultural Sciences. The project was subsequently moved forward and industrially developed by BioProdex, Inc., a company founded by Dr. Charudattan. The University of Florida Research Foundation, which holds two patents on the use of Tobacco mild green mosaic virus-mediated lethal hypersensitive response as a

novel method of weed control (Charudattan et al., 2004, 2009), licensed BioProdex to develop and commercialize this technology. For its part, BioProdex, through R&D and testing funded by USDA-National Institute of Food and Agriculture-Small Business Innovation Research grants, developed an industrial process to mass produce the virus, formulated a commercial product, assembled a registration data package, and, with the help of the IR-4 Biopesticide and Organic Support Program, Princeton, NJ, successfully registered the product, SolviNix® LC.

Tobacco mild green mosaic virus (TMGMV) has been known for nearly 70 years as a pathogen of tobaccos (Nicotiana spp.), peppers (Capsicum spp.), and about 20 other species mostly in the Solanaceae (Brunt et al., 1996; Wetter, 1989). It was first described as a mild strain of Tobacco mosaic virus (TMV) and has been named variously as Green tomato atypical mosaic virus, Para-tobacco mosaic virus, Tobacco mosaic virus-South Carolina mild mottling strain, Tomato atypical mosaic green mottling strain, Tobacco mosaic virus strain U2, and Tobacco mosaic virus strain U5. It is now classified as a distinct Tobamovirus species, Tobacco mild green mosaic tobamovirus, with two naturally occurring strains, U2 and U5 (ICTVdB, 2006). An isolate of the U2 strain is used as the active ingredient in SolviNix® LC (Hiebert et al., 2007). TMGMV probably occurs worldwide in tropical and subtropical regions where Nicotiana glauca (tree tobacco), a natural host to this virus, is distributed (Brunt et al., 1996; Wetter, 1989). Normally it is found at low frequencies in N. glauca and some cultivars of tobacco and pepper but is not known to cause serious economic losses. For instance, both U2 and U5 strains of TMGMV are prevalent in California where several susceptible solanaceous

hosts are cropped, grown as ornamentals, or distributed naturally without suffering significant economic or environmental losses from the virus. Nonetheless, lately there have been a few reports of TMGMV incidence in clonally propagated plants and transplants raised in plant nurseries. In this case, the source of primary inoculum is most likely virus-containing tobacco products (cigarettes, chewing tobacco) used by nursery workers while the secondary inoculum is probably spread by the repeated handling of the planting material and the use of contaminated pruning and cutting tools. When such unnatural infections do occur in field-grown or greenhouse-grown crops, the source of the TMGMV infection can be identified and remedial actions taken to eradicate the virus. Typically, TMGMV causes a mild, green, mosaic symptom in susceptible hosts but in tropical soda apple it elicits a lethal hypersensitive response manifested as systemic necrosis and plant death (Charudattan and Hiebert, 2007). Application of TMGMV U2 to tropical soda apple plants by certain application methods such as high-pressure foliar spray produces > 85% control (weed kill) in about 6 weeks post-application. Just one application of the virus to a few physiologically active leaves on a plant is sufficient to infect and kill the entire plant. The wilted plant does not recover, and the entire plant, including the root system, is killed. Looking back over time, plant viruses have received only limited attention as possible weed biocontrol agents (e.g., Charudattan, 1979; Elliott, et al., 2009; Epstein and Hill, 1999; Izhevsky, 1979; Randles, 1986). The limited interest is perhaps explained by the prevailing, justified notion that viruses generally have a broad host range and high genetic variability and are difficult to contain because most are spread by insect or other mobile vectors that are hard to confine. It is therefore understandable that despite the well-known fact that viruses can reduce plant growth and reproduction and thereby lessen the competitive ability of plant (weed) populations, Kazinczi et al., (2006), who have studied virus-weed interactions at great depth, have declared that “viruses cannot be used for biological weed control.” We, on the contrary, were prompted by certain unique and interesting aspects of the tropical soda apple-TMGMV U2 system that suggested safety as well as the probability of success. First and foremost, TMGMV U2 is capable of KILLING the tropical soda apple plant fairly quickly and consistently, which is a rare feature among plant viruses. The virus is mechanically transmitted and has no known, confirmed vector capable of spreading it. Therefore, it could be used in target-directed applications without the risk of secondary spread. Moreover, despite its worldwide occurrence, TMGMV U2 is genetically stable, as evidenced by the low frequency of emergence of new strains in nature (Fraile et al., 1996, 1997). Finally, based on published literature it was clear that we could mass produce the virus to serve the market needs. So, in retrospect, we are glad we saw an opportunity in this host-virus system rather than being constrained by notions of possible risks in using a virus. So what comes next? The bioherbicide target, tropical soda apple, is a South American plant that has become invasive in the southeastern USA, Australia, Brazil, and several other countries. It is designated a Noxious Weed in the United States and a Class 2 Regionally Prohibited Weed across New South Wales, Australia. While it is a weed mainly in pastures and natural areas, it is also known to affect crops in some countries. BioProdex intends to explore the possibility of registering SolviNix in other countries and to continue testing to discover additional weed targets for this bioherbicide. For more information about SolviNix® LC please visit www.bioprodex.com. Literature Cited Brunt, A.A., Crabtree, K., Dallwitz, M.J., Gibbs, A.J., Watson, L., and Zurcher, E.J. (Eds.). 1996. Plant

Viruses Online. Descriptions and Lists from the VIDE Database. Tobacco mild green mosaic tobamovirus. Online: http://pvo.bio-mirror.cn/descr801.htm. Accessed Jan. 3, 2015.

Charudattan, R. 1979. Composition and process for controlling milkweed vine. U.S. Patent No. 4,162,912. July 31, 1979.

Charudattan, R. and Hiebert, E. 2007. A plant virus as a bioherbicide for tropical soda apple, Solanum viarum. Outlooks on Pest Management 18:167-171.

Charudattan, R., Pettersen, M.S., and Hiebert, E. 2004. Use of Tobacco mild green mosaic virus (TMGMV)-mediated lethal hypersensitive response (HR) as a novel method of weed control. U.S. Patent No. 6,689,718 B2. February 10, 2004.

Charudattan, R., Pettersen, M.S., and Hiebert, E. 2009. Use of Tobacco mild green mosaic virus (TMGMV)-mediated lethal hypersensitive response (HR) as a novel method of weed control. U.S. Patent No. 7,494,955 B2. February 24, 2009.

Elliott, M.S., Massey, B., Cui, X., Hiebert, Charudattan, R., E., Waipara, N., and Hayes, L. 2009. Supplemental host range of Araujia mosaic virus, a potential biological control agent of moth plant in New Zealand. Australasian Plant Pathology 38:603–607.

Epstein, A. H. and J. H. Hill. 1999. Status of rose rosette disease as a biological control for multiflora rose. Plant Disease 83:92-101.

Fraile, A., Escriu, F., Aranda, M.A., Malpica, J.M., Gibbs, A.J., and Garcia-Arenal, F. 1997. A century of tobamovirus evolution in an Australian population of Nicotiana glauca. Journal of Virology 71:8316-8320.

Fraile, A., Malpica, M., Aranda, M.A., Rodriguez-Cerezo, E., and Garcia-Arenal, F. 1996. Genetic diversity in Tobacco mild green mosaic tobamovirus infecting the wild plant Nicotiana glauca. Virology 223:148-155.

Hiebert, E., Charudattan, R., Horrell, J., Maia, G.S., and Elliott, M.S. 2007. Characterization of a tobacco mild green mosaic tobamovirus isolated from a gesneriad in the USA. GenBank accession # EF469769.

ICTVdB Management. 2006. 00.071.0.01.011. Tobacco mild green mosaic virus. In: ICTVdB - The Universal Virus Database, version 4. Büchen-Osmond, C. (Ed), Columbia Univ., New York. Available online: http://ictvdb.bio-mirror.cn/ICTVdB/00.071.0.01.011.htm. Accessed Jan. 3, 2015.

Izhevsky, S.S. 1979. The application of pathogenic microorganisms for control of weeds in the U.S.S.R. Page 35, in: J.R. Coulson, Ed., Proceedings of the Joint American-Soviet Conference on Use of Beneficial Organisms in the Control of Crop Pests. Aug. 13-14, 1979, Washington, DC. Published by the Entomological Society of America, College Park, MD, USA. ISBN 0-938522-08-6.

Kazinczi, G., Horváth, J., and Takács, A.P. 2006. On the biological decline of weeds due to virus infections. Acta Phytopathologica et Entomologica Hungarica 41: 213-221.

Randles, J.W. 1986. Susceptibility of Echium plantagineum L. to tobacco mosaic, alfalfa mosaic, tobacco ringspot, and tobacco necrosis viruses. Australasian Plant Pathology 15:74-77.

Wetter, C. 1989. Tobacco mild green mosaic virus. In: AAB Description of Plant Viruses No. 351. Online: http://www.dpvweb.net/dpv/showadpv.php?dpvno=351. Accessed Jan. 3, 2015.

Alternaria alternata and its metabolite isolated from Croftonweed (Ageratina adenophora) as a potential agent for weed control Alternaria alternata was firstly identified as a natural enemy of Croftonweed (Ageratina adenophora, syn: Eupatorium adenophorum), one of the most troublesome invasive alien weeds worldwide. The potential of both conidia and mycelia of this fungus for biological control have been systematically evaluated. Mycelia fragments blended with culture media could kill the weed quickly. AAC-toxin isolated form A. alternata mainly contributed this effectiveness. Furthermore, our studies have mainly focused on active ingredients of the metabolites from this fungus and their action target and mechanism. The main active ingredient of AAC-toxin was identified as Tenuazonic acid (TeA), which was poorly

understood for its herbicidal activity. TeA demonstrates broad spectrum, killing the most of grass, broadleaf and sedge weeds tested. It causes weed damage through inhibiting of weed photosynthesis. Its action target and mechanism on inhibition of weed photosynthesis were thoroughly studied. Our studies suggest that the most key and important action site of TeA is that it interrupts electron transport beyond QA on the acceptor side of PSII by competing with QB for the QB-binding site. TeA causes an increase of heat sink centers (non QA reducing centers) and inactivation of the Fd-NADP+reductase (FNR) system and the reduction of nicotinamide adenine dinucleotide phosphate (oxidized form, NADP+), which is different from those known classic PSII herbicides (e.g. atrazine and diuron). The molecular interaction model, based on evidence from the competition experiments with [14C]atrazine and D1-mutants of Chlamydomonas reinhardtii, shows that TeA does not share the same binding environment with atrazine and diuron despite their common action target: the QB-site. It is the No. 256 not 264 amino acid plays a key role in TeA binding to the QB-niche. Obviously, TeA is a member of a novel class of PSII inhibitors. Meanwhile, to further clarify the mechanism of TeA binding to QBniche, a series of TeA analogues were synthesized using natural amino acid as former body, which differ only in side chain at the 5-position (Fig. 7). The herbicidal activity of TeA analogues positively related to number of carbons at the alkyl side chain. Hence, it is inferred that most of tetramic acid group may be potential PSII inhibitors. When leaves are exposed to TeA under light, with that PSII electron transport beyond QA and the reduction of end acceptors on the PSI acceptor side and chloroplast ATPase activity are inhibited, followed occurrence of charge recombination, electron leakage to O2 and thylakoid overenergization, resulting in the chloroplast-derived Reactive Oxygen Species (ROS) eruption in plant cells. These ROS include not only singlet oxygen (1O2) but also superoxide anion (O2

.-), hydrogen peroxide (H2O2) and hydroxy radical (.OH). In particular, TeA-induced singlet oxygen (1O2) activated a signaling pathway that depends on the two EXECUTER (EX) proteins EX1 and EX2 and triggered a programmed cell death response. In arabidopsis seedlings treated with TeA at half-inhibition concentration 1O2-mediated and EX-dependent signaling is activated as indicated by the rapid and transient up-regulation of 1O2-responsive genes in wild type and its suppression in ex1/ex2 mutants. An excess of ROS attacks directly pigments, lipids, proteins and DNA, and then causes chlorophyll breakdown, electrolyte leakage, lipid peroxidation, cell membrane disruption, nucleus damage and, subsequently, leads to cell destruction and leaf tissue necrosis and ultimately kills the plants. This is important to further understand the mechanism of interaction between phytotoxin TeA and host plants. The research is also helpful to promote the commercial process of TeA as a novel bioherbicide. It can be concluded that TeA has broad-spectrum, rapid, low residual and high herbicidal activity similar to that of paraquat and may have the potential to be developed into a microbe-based herbicide. Further research works is focusing on TeA biosynthesis pathway and related genes within the fungus.

Related publications 1. Qiang Sheng and Summerell Brett A. Pathogenicity of Alternaria alternata on crofton weed (Eupatorium

adenophorum). 1999. The Proc. of 17th Asian-Pasific Weed Science Society Conference, pp345-347. Thailand Plant Protection Society

2. Qiang S., Summerell B.A. and Li Y.H. Evaluation of mycelium virulence of Alternaria alternata to Eupatorium adenophorum, The Proceedings of Asian-pacific Weed Sci. Soc. Conf. 2001, 2, Beijing:The Standard Press: 105-112

3. WAN Zuoxi, ZHU Jing jing , QIANG Sheng. The pathogenic mechanism of toxin of Alternaria alternata ( Fr. ) Keissler to Eupatorium adenophorum. Journal of Plant Resources and Environment, 2001, 10(3):47-50.

4. Wan Zuoxi, Qiang Sheng,Wu Yongyao. Separation and Activity Determination of Alternaria alternata Toxin. JOURNAL OF BEIHUA UNIVERSITY(Natural Science), 2001.2(5):428-430

5. WAN Zuoxi, ZHOU Guanglai, QIANG Sheng. Screening of toxin-producing isolates and culture medium of Alternaria alternata. Journal of Hubei Institute for Nationalities (Nat. Sci.) 2001, 19,(3): 7-10

6. WAN Zuoxi, QIANG Sheng, XU Shangcheng, SHEN Zhenguo, DONG Yunfa. Culture conditions for production of phytotoxin by Alternaria alternata and plant range of toxicity. Chinese Journal of Biological Control, 2001, 17 (1), 10-15

7. QIANG Sheng, CHANG Ying, WAN Zuoxi , LI Yanghan. Comparison on pathogenicity and other characteristics of five isolates of Alternaria alternata from Eupatorium adenophorum. Journal of Nanjing Agricultural University, 2002 , 25 (4): 23-27

8. CHANG Ying,WANG Xuedong,QIANG Sheng.Effect of Alternaria alternata toxin on ultrastructure ofleaf tissue of Eupatorium adenophorum Sprengel. Journal of Chinese Electron Microscopy Society, 2004, 23 (5): 566-570.

9. DAI Xin-bin, CHENG Shi-guo, QIANG Sheng,AN Chuan-fu, ZHANG Rong-xian. Effect of Toxin from Alternaria alternata (Fr.) Keissler on leaf photosynthesis of Eupatorium adenophorum Spreng. 2004. 34 (1): 55-60

10. FU Jian-Guo, QIANG Sheng, ZHU Yun-Zhi. Protoplast preparation and mutation for pathogenicity of Alternaria alternata (fr.) Keissler by restriction enzyme mediated integration (REMI). Mycosystema, 2005, 24(3): 407-413.

11. CHANG Ying, WANG Yiquan, QIANG Sheng. Pathogenicity and genetic diversity of Alternaria alternata strains. Chin J Appl Environ Biol., 2005, 11 (4): 486-489

12. Chen Shiguo, Dai Xinbing, Qiang Sheng. Effect of Toxin from Alternaria alternata (Fr.) Keissler on electron transfer activity of chloroplast in Eupatorium adenophorum Spreng. Plant Pathology (SCI), 2005, 54(5): 671-677

13. Qiang S, Zhu YZ, Summerell B A, Li Y H. Mycelium of Alternaria alternata as a potential biological control agent for Eupatorium adenophorum. Biocontrol Science & Technology (SCI), 2006, 16(7): 653-668.

14. ZHOU Bing & QIANG Sheng.Effect of Tenuazonic Acid Produced by Alternaria alternata on Micronucleus and Karyokinesis of Vicia faba Root Tip Cells. Chin J Appl Environ Biol, 2007, 13 (6) : 803-806

15. ZHOU Bing , AN Chuan2 fu , DONG Yun2 fa , QIANG Sheng. Isolation of Alternaria alternata toxin using macroporous resins. Journal of Zhejiang Forestry College, 2007, 24 (2): 198-202

16. ZHOU Bing, QIANG Sheng. Degradation of Tenuazonic Acid from Alternaria alternata in Soil. Journal of Agro-Environment Science, 2007, 26(2): 572- 576

17. Chen SG, Dai XB, Xu XM, Yang CL, Qiang S. Identification of tenuazonic acid as a novel type of natural photosystem II inhibitor binding in QB-site of Chlamydomonas reinhardtii. BBA Bioenergetics (SCI), 2007, 1767: 306-318, doi:10.1016/j.bbabio.on line (IF3.84)

18. Zhou B, Qiang S. Environmental, genetic and cellular toxicity of tenuazonic acid isolated from Alternaira alternata. African Journal of Biotechnology (SCI), 2008, 7 (8):1151-1156

19. WEI Ran, WANG Ling, QIANG Sheng. High-performance liquid chromatography Improvement of detection technique of tenuazonic acid in Alternaria alternata cultures through High-performance liquid chromatography. Jiangsu Agriculture Science, 2009, (6):413-414

20. ZHOU Bing, YAN Xiaohong, GUO Nianmei, JI ANG Ping, ZHONG Juan, QIANG Sheng. Physiological effects of tenuazonic acid from Alternaria alternata on Alternanthera philoxeroides Leaves. Jiangsu J. of Agr. Sci., 2010 , 26( 3 ): 503- 507

21. Chen SG, Yan CY, Qiang S, Zhou FY, Dai XB. Chloroplastic oxidative burst induced by tenuazonic acid, a natural inhibitor, triggers cell necrosis in Eupatorium adenophorum Spreng. Biochemica et Biophysica Acta, Bioenergetics (SCI), 2010,1797:391-405 (IF5.13)

22. Chen Shiguo, Dai Xinbin, Qiang Sheng, Xu Xiaoming Action of tenuazonic acid, a natural phytotoxin, on photosystem II of spinach. Environmental and Experimental Botany (SCI), 2008, 62: 679-689. doi:10.1016/j.envexpbot (IF2.3)

23. Zhao Yong Zhu, Qing Ming Shi, Bao Feng Han, Xian Feng Wang, Sheng Qiang, Chun Long Yang*. Synthesis, Characterization and Biological Activities of Novel (E)-3-(1-(Alkyloxyamino)ethylidene)-1-alkylpyrrolidine-2,4-dione Derivatives[J]. Bull. Korean Chem. Soc. 2010, 31(9): 2467-2472.

24. Zhao-Yong Zhu, Xian-Feng Wang, Fan-Gui Meng, Qing-Bin Li, Xiao-Qian Zheng, Sheng Qiang, Chunlong Yang*. Synthesis, Characterization and Biological Activities of Novel (Z)-3-((E)-1-(alkyloxyimino)ethyl)-5-arylidene-4-hydroxypyrroline-2-one Derivatives[J]. J. Heterocyclic Chem. 2010, 47: 1328-1334.

25. Xian-Feng Wang, Teng-Fei Si, Qing-Bin Li, Zhao-Yong Zhu, Xian-Jie Zhu, Sheng Qiang, and Chun-Long Yang*. Synthesis, characterization and biological activity of novel (5-RS,6-S)-5-sec-butyl-3-(1-substituted-amino)ethylidene-1H-pyrrolidine-2,4-diones[J]. ARKIVOC(SCI), 2010, (ii): 31-48.

26. Xiao-Qian Zheng, Bao-Feng Han,Xian-Feng Wang,Sheng Qiang, Chun-Long Yang*. Synthesis and bioactivity of novel (Z,E)-1-(substituted phenyl)-3- [α-(alkyloxyimino)benzylidene] pyrrolidine-2,4-dione derivatives[J]. Heterocycl. Commun. 2011, 17(1-2): 73-78.

27. Sheng Qiang, Ling Wang, Ran Wei, Bing Zhou, Shiguo Chen, Yunzhi Zhu, Yunfa Dong, and Chuanfu An. Bioassay of the herbicidal activity of AAC-Toxin produced by Alternaria alternata isolated from Ageratina adenophora. Weed Technology(SCI) 2010 24:197–201 DOI: 10.1614/WT-D-09-00016.1 (IF 0.93)

28. Chen Shiguo, Zhou Fengyan, Strasser Reto Jörg, Yang Chunlong, Qiang Sheng. Application of fast chlorophyll a fluorescence kinetics to probe action target of 3-acetyl-5-isopropyltetramic acid. Environmental & Experimental Botany(SCI), (2011), 71: 269-279. doi:10.1016/j.envexpbot.2010.12.013 (IF 2.7)

29. Chen Shiguo, Yin Chunyan, Strasser Reto Jörg, Govindjee, Yang Chunlong, Qiang Sheng. Reactive oxygen species from chloroplasts contribute to 3-acetyl-5-isopropyltetramic acid-induced leaf necrosis of Arabidopsis thaliana. Plant Physiology and Biochemistry, 2012, 52:38-51 (IF 2.40)

30. Kang Ye, Feng-yan Zhou, Shi-guo Chen, Sheng Qiang. A key role of MAPK pathway in the pathogenic mechanism of Alternaria alternata (Fr.) Keissler. Proceedings of the 11th IBG Workshop, Nanjing, China. 2013, P25.

31. Zhou Fengyan, Chen Fanghui, Qiang Sheng. Identification of genes related to TeA toxin synthesis of Alternaria alternata by suppression subtractive hybridization(SSH). Proceedings of the 11th IBG Workshop, Nanjing, China. 2013, P42.

32. Shiguo Chen, Reto Jörg Strasser, Sheng Qiang. In vivo Assessment of Effect of Phytotoxin Tenuazonic Acid on PSII Reaction Centers. Plant Physiology and Biochemistry. 2014 on line

33. Chen SG et al., Blocking the QB-binding site of photosystem II by tenuazonic acid, a non-host-specific toxin of Alternaria alternata, activates singlet oxygen-mediated and EXECUTER-dependent signaling in Arabidopsis. Plant Cell and Environment 2014, doi: 10.1111/pce.12462

34. Shiguo Chen, Ye Kang, Differential sensitivity to the potential bioherbicide tenuazonic acid probed by the JIP-test based on fast chlorophyll fluorescence kinetics. Environmental and Experimental Botany (Impact Factor: 3). 04/2015; 112.

Patents 1. Qiang Sheng, et al., 2003. A technique of metabolite of Alternaria alternata for biological control of weeds.

Patent number:ZL001125605(China) 2. Qiang Sheng et al. 2005. A technique for mass production of bioherbicide. Patent

number：ZL03132322.7(China)

3. Qiang Sheng et al. 2005. A technique using metabolites of Alternaria alternata isolated from Eupatorium adenophorum to biocontrol weeds. ZL200510038263.2; PCT/CN2005/002367(2005); International patent number: WO2006079275; 4982384(Japan,2013)

4.Qiang Sheng, Chen Shiguo, Yang Chunlong, Dai Xinbing, Dong Yunfa. 2006. Structural modifiers from a biobased substance and its application to control weeds. Application number: PCT/CN2006/001315(2006); WO2007033544, USA Patent No.: 8921274 (2014).

5. Qiang Sheng, Lu Yannan, Zhu Yunzhi, Gao Tongjun, Xu Chunfeng. Production method of the mixture of bioherbicide. ZL201010199842.6 (China)

Sheng Qiang, Weed Research Laboratory, Nanjing Agricultural University, China - [wrl@njau.edu.cn]

Activities on bioherbicides and classical biocontrol of weeds at the Universidade Federal de Viçosa (Brazil) Bioherbicides Numerous fungi have been preliminarily evaluated as potential bioherbicides against important agricultural weeds in Brazil in our lab, several of which appearing, at first, to

have great potential. In order to avoid the problems experienced by many of the pioneering projects, we have chosen targets of high economical importance and for which management with chemical herbicides is widely considered as complicated either because of plant habit or because of existing herbicide resistance. Among these are: Cyperus rotundus (purple nutsedge), Euphorbia heterophylla (wild poinsettia), Conyza spp. (horse weed) and Commelina benghalensis (wandering Jew). Several students in our Plant Pathology post-grad programme have undertaken research work on fungi found on these target weeds as part of the preparation of their thesis. The studies on wild poinsettia resulted in the finding and description of a novel fungal species, Lewia chlamidosporiformans. Research on the biocontrol potential of this fungus led to a bioherbicide patent being filed by the Universidade Federal de Viçosa. This is the first patent request on a bioherbicide in Brazil and, perhaps because of the novelty of the issue, this is still under evaluation by the government after nearly ten years. Progress towards the final development of a product in that case and others have been hampered by the lack of involvement by the industry. Unfortunately, in our views, the bioherbicide approach depends heavily on a big commercial success story in order to raise the interest of the industry. Ironically we are presently assisting in Brazil, as well as in other countries, a change of attitude of the industry in favour to biopesticides. Strangely, bioherbicides are still being left out. There are certainly problems in mass production and formulation that need to be addressed in order to change the state of things in bioherbicides and it is not sufficient just to chose the right target weeds. Recently we established a cooperation with Agriculture Canada and one of our students will spend part of 2015 in the labs at Saskatoon under the supervison of our colleague Susan Boyetchko working on the fermentation technology and formulation of one of our high potential bioherbicide candidates. Classical biological control Our group has worked in cooperation with organizations abroad on classical biocontrol of weeds native from Brazil that became invasives in introduced situations for over twenty years. Target weeds have been Miconia calvescens (Melastomataceae), Lantana camara (Verbenaceae), Schinus terebinthifolius (Anacardiaceae) and Tradescantia fluminensis (Commelinaceae). Surveys of the pathogenic fungi associated to each of these weeds were performed and resulted in lists including some pathogens having clear potential for use as biological control agents. • Miconia- Colletotrichum gloeosporioides f. sp. miconiae has been introduced into

Hawaii and French Polynesia around 15 years ago and although established in both archipelagos and providing some degree of control in French Polynesia, it is clearly insufficient for adequate levels of control of infestations to be reached. Insects are being investigated by colleagues in Hawaii in quarantine and another fungus Coccodiella miconiae – a fungus causing a rust-like disease (yellow pustule) – had important aspects of its biology resolved and a protocol for the production of viable and infective inoculum was finally developed, paving the way for its possible use against miconia. Additionally, a newly described species of nematode Ditylenchus gallaeformans that is capable both to attack M. calvescens and C. hirta, is showing great potential for use against invasive Melastomataceae. Funding was obtained by Maui Invasive Species Committee and in the near future the research on this nematode will restart.

• Lantana- The rust Prospodium tuberculatum has been introduced into Australia over 10 years ago and its establishment was challenged by long years of draught. At one stage the rust was thought to be lost. More recently, with more favourable weather the rust reappeared, inclusive in areas far distant from the release sites. Unfortunately the

strain appears to be too host-specific and only infects some of the populations of lantana. There has been no recent activities in our lab on the biocontrol of this weed recently.

• Brazilian pepper tree – A long list of fungi was obtained during the surveys on S. terebinthifolius and, after several years of survey, the list is still increasing. At present, two fungi are being evaluated under quarantine by colleagues in the USDA: Septoria sp. and Corynespora cassiicola f. sp. schini.

• Wandering Jew – A white smut-like disease causing fungus – Kordyana sp. was selected among the numerous fungi collected on T. fluminensis and is now being evaluated in a quarantine lab at CSIRO for later introduction in Australia and New Zealand. Its high host-specificity has been confirmed and an official request for release is under preparation.

Surveys on numerous other weeds of world relevance that are native from Brazil have been performed along the years by our team and numerous fungal pathogens with clear potential for use in classical biocontrol were collected. Unfortunately, we have assisted a progressive decrease in funding for classical biocontrol worldwide and the influx of new projects with funding from external sources have diminished dramatically. • Rubber vine - One novelty for Brazil is the effort that is now being made by our team

together with CABI and colleagues at the Universidade Estadual do Ceará to start what will be the first example in Brazilian history of a project on classical biocontrol of a weed in Brazil. This will be against rubber vine (Cryptostegia madagascariensis) – in Brazil known as Devil’s claws. This vine is capable of smothering vast areas of intact forest forming impenetrable masses that can kill trees and prevent animal and human movement. It produces a large seed bank and abundant toxic latex rendering its control through standard methods extremely difficult, as well as hazardous. In Brazil, it is infesting vast areas of native semi-arid vegetation and is a particular threat to the carnauba palm and riverine vegetation associated with this palm. Carnauba is often referred to as the “tree of life” and is the symbolic tree of two Northeast states (Ceará and Rio Grande do Norte), being included in the coat of arms of these two states. It is the sole source of a very valuable natural wax which has been sustainably harvested for over a century by local communities in the northeast. Rubber vine climbs the carnauba trunks and upon reaching the canopy entangles established leaves and stops shoot expansion. Eventually, the dense mass of vines smothers the slow-growing and heliophilous carnauba, leading to its death. Extensive areas of traditional harvesting of carnauba wax have already been abandoned and there is no clear obstacle to the expansion of this invasive alien plant. If no action is taken, both a valuable resource and a unique ecosystem will be lost to Brazil and to the world. There is no conflict of interest over this species as it has no uses other than as a minor gardening plant. It is closely related to C. grandiflora, a well studied species sharing many similarities with C. madagascariensis including its propensity to become a pernicious weed in tropical, semi-arid regions.Given its similarity to C. grandiflora, biological control with a rust fungus is likely to be a highly feasible management option for Brazil. A rust fungus from Madagascar which was researched by CABI - Maravalia cryptostegiae - has been released in Australia to control the weed over a 40,000 km2 invaded area. Its release resulted in excellent and fast control of rubber vine. Rust impact on rubber vine allowed native species and entire ecosystems to recover, as well halting further spread, and it is now heralded as a highly successful example of classical biological control of an exotic weed. The fact that a related species has been so successfully controlled elsewhere, and that much of the relevant research has already been carried out, is a great advantage for an initiative against C. madagascariensis in Brazil, piggybacking on the successful Australian experience. Again, the major challenge has been that of

obtaining the necessary funds under a scenario of financial crisis to move ahead with this project.

Robert Barreto [rbarreto@ufv.br]

UPCOMING MEETINGS OF INTEREST

17th European Weed Research Society Symposium Weed management in changing environments Montpellier, France June 23-26, 2015 http://ewrs2015.org/ 13th World Congress on Parasitic Plants Parasitic plants: the good, the bad, and the mysterious Kunming, China July 5-10, 2015 http://wcpp13.csp.escience.cn/dct/page/1

RECENT PUBLICATIONS & PRESENTATIONS A World Catalogue of Agents and Their Target Weeds The fifth edition of A World Catalogue of Agents and Their Target Weeds is finally available! The hard copy version of the catalogue is being printed now and will be available in January 2015. I will again be in touch at that time to help facilitate its distribution. The online version, current through 2014, is available now at http://www.ibiocontrol.org/catalog/. The structure of the online version was created by the University of Georgia and includes querying capabilities to allow for sorting by key pieces of information. Clicking on individual releases will bring you to the full information available, along with supporting references. A pdf of the printed version (current through 2012) is also available on the website. Please feel free to share the link or this email with anyone that might be interested. Funding for both the print and online versions of the catalogue was provided by the United States Forest Service (Forest Health Technology Enterprise Team). Work was conducted by MIA Consulting, the University of Georgia, the Queensland Department of Agriculture, Fisheries & Forestry, the University of Idaho, and the Centre for Agricultural Bioscience International. The future of the online database is uncertain. If you have any changes or updates to information included therein, please send them to me (Rachel Winston, rachel@getmia.net<mailto:rachel@getmia.net>). Though changes will not be immediately incorporated in the dataset, I will compile all edits until the best course of action for the database is determined.

Thank you all very much for your assistance and patience in this endeavor. It is only with your input that this thorough update was possible. We hope the database proves useful to the field of weed biological control. With very best wishes to you all for the new year, The Catalogue Update Team Rachel Winston [rachel@getmia.net]

Impact of macrocidins, produced by Phoma macrostoma, on carotenoid profiles of plants M. Hubbard, R.K. Hynes, K.L. Bailey Highlights

• Macrocidins induce changes in carotenoid profiles of susceptible, but not resistant, plants.

• Symptoms and carotenoid content of macrocidin- and diflufenican-treated plants differ.

• Macrocidins likely act on more than one step of carotenoid biosynthesis.

• First proof that macrocidins impact carotenoid biosynthesis.

Abstract Phoma macrostoma (Montagne) is a bioherbicide that controls broadleaf weeds such as Canada thistle (Cirsium arvense L. (Scop.)) and dandelion (Taraxacum officinale Weber ex F.H. Wigg.), while leaving crop plants, such as wheat (Triticum aestivum L.) and pumpkin (Cucurbita L. spp), unharmed. The bioherbicidal activity of P. macrostoma is largely due to the production of phytotoxic secondary metabolites, known as macrocidins. While macrocidins produce photobleaching symptoms in susceptible plants, the mechanism(s) by which this occurs are not known. The hypothesis that macrocidins inhibit carotenoid biosynthesis was tested by comparing the carotenoid profiles and other physiological parameters of macrocidin-treated Canada thistle, dandelion, pumpkin and wheat with untreated control plants and plants treated with the known carotenoid biosynthesis inhibitor, diflufenican. Only in susceptible plants, macrocidins induced photobleaching symptoms, lowered total chlorophyll content and reduced photosynthetic gas exchange while increasing the percentage of the carotenoid biosynthesis intermediate phytoene. In addition, macrocidin treatment led to a decrease in the β-carotene to lutein ratio in thistles. While diflufenican also led to chlorosis in dandelion and thistles, its impacts differed from those of macrocidins in that diflufenican-treated dandelion, thistle and pumpkin had increased total carotenoid content compared to the control. Diflufenican-treated dandelion and thistle contained 83 ± 2% and 91 ± 2% phytoene, respectively. In contrast, macrocidins-treated dandelion and thistle (at the higher dose) contained 45 ± 10% and 64 ± 5% phytoene, respectively. The β-carotene to lutein ratio in diflufenican-treated thistles did not differ from that of the control. This paper is the first proof that macrocidins impact the carotenoid biosynthesis by inhibiting the carotenoid biosynthetic enzyme phytoene desaturase (PDS) and at one or more other steps in carotenoid biogenesis. References Hubbard, M, Hynes, R.K, Erlandson, M., and Bailey, K.L. 2015. The biochemistry behind biopesticide

efficacy. Sustainable Chemical Processes, 2:18, DOI: 10.1186/s40508-014-0018-x. Open Access online provisional posted December 2014.URL http://www.sustainablechemicalprocesses.com/content/2/1/18

Bailey, K.L. 2014. The bioherbicide approach to weed control using plant pathogens. Pages 245-266 In Integrated Pest Management: Current Concepts and Ecological Perspective, D.P. Abrol (Ed.). Elsevier, San Diego, CA.

Michael Cripps, Karen, Bailey, Charles Merfield, Sarah Jackman, and Graeme Bourdot. 2014. The search for “white tip” of Californian thistle in New Zealand. Poster presentation at NZ plant Pathology meeting. 19th Australasian Plant Pathology Society, Nov 25-28, Auckland, NZ.

Hubbard, M, Derby, J, Hupka, D, Hynes, RK and Bailey, K. 2014. Exploring the mode(s) of action of macrocidins, the phytotoxins produced by the bioherbicidal fungus Phoma macrostoma. Invited oral presentation at the 2014 Canadian Forum for Biological Control Symposium. Saskatoon, SK September 28 – October 1, 2014.

Hubbard, M, Hupka, D, Bailey, K, and Hynes, R. 2014. The bioherbicidal metabolites of the fungus Phoma macrostoma inhibits lycopene β-cyclase in the carotenoid biosynthetic pathway in susceptible hosts. Oral presentation at the 2014 International Union of Microbial Societies Congresses. Montreal, QC July 27 – August 1, 2014.

Hynes, R.K. Michelle Hubbard, M., Bailey, K.L. Bioherbicide Phoma macrostoma for field crops. International Union of Microbiological Societies, Montreal, P.Q. July 27-August 1.

Mupondwa, E.K., Li, X., Boyetchko, S., Hynes, R. K., Geissler, J. 2015. Technoeconomic analysis of large scale production of pre-emergent microbial bioherbicide in Canada. Bioresource Technology 175: 517-528.

Boyetchko, S.M., Hynes, R.K. and de la Bastide, P.Y. 2013. Setaria viridis (L.) Beauvois, Green Foxtail (Poaceae). Ed. P.G. Mason and D.R. Gillspie. CMI Biological Control Programs in Canada, 2001 to 2012. pp. 370-377.

McClay, A.S., Peng, G., Bailey, K.L., Hynes, R.K., Hinz, H.L. 2013. Tripleuropermum inodorum (L.) Sch. Bip., Scentless Chamomile (Asteraceae). Ed. P.G. Mason and D.R. Gillspie. CMI Biological Control Programs in Canada, 2001 to 2012. pp. 391-401.

EDITOR'S CORNER Dear All, Thanks for the contribution received for the preparation of this issue of the bulletin. After several unsuccessful attempts, this time we were able to produce an interesting issue of the International Bioherbicide Group Newsletter. I hope this trend will continue in the future, as a renewed interest for weed biocontrol seems to appear on the horizon. In particular, please let me thank (in alphabetical order):

- Karen Bailey

- Robert Barreto

- Susan Boyetchko

- Raghavan Charudattan

- Michelle Hubbard

- Russell Hynes

- Sheng Qiang

- Rachel Winston Please remember that this bulletin is prepared on a voluntary basis and it contains only the information sent by the newsletter subscribers, under their responsibility. Only some editorial changes could be done to the material received.

The newsletter is not an official journal and cannot be considered exhaustive. Please also remember that the mailing list can be used as a moderated list for distributing information related to weed biocontrol at any time during the year. Please feel free to deliver the newsletter to any person that could be interested in it, or invite him/her to subscribe the mailing list. To subscribe please go to the following web address: http://nautilus.area.ba.cnr.it/mailman/listinfo/ibg-news and follow the instructions Thanks. Regards