How To Control Black Sigatoka

Transcription

1 ACTION PLAN for BLACK SIGATOKA Mycosphaerella fijiensis (Morelet) DECEMBER 2006 IICA OFFICE IN SAINT LUCIA

2 WHAT IS IICA The Inter-American Institute for Cooperation on Agriculture (IICA) is a specialized agency of the Inter-American System, and its purposes are to encourage and support the efforts of its Member States to foster agricultural development and rural well-being in their territories. With more than six decades of institutional life, the Institute is responding to new mandates issued by the Heads of State and Government of the Americas, the General Assembly of the Organization of American States (OAS) and the ministers of agriculture of the Americas, to reposition itself so that it can meet both the new challenges facing agriculture and the requests for support it receives from its member countries. As it pursues its vision and mission, the Institute has competitive advantages it can draw on to carry out its new role. It has accumulated a wealth of knowledge regarding agriculture and the rural sector, the diversity of peoples and cultures, and the agro-ecological diversity of the hemisphere, all of which are important for crafting creative solutions to a wide variety of problems and challenges. Its presence in all of the Member States gives the Institute the flexibility it needs to move resources between countries and regions, in order to design and adapt cooperation initiatives intended to address national and regional priorities, facilitate the flow of information and improve the dissemination of best practices. The Institute has its Headquarters in Costa Rica, and Offices in 34 countries of the Americas, as well as an Office for Europe located in Madrid, Spain. The Directorate for Strategic Partnerships works out of the IICA Office in Washington, D.C.

3 ISSN CaRC/LC ACTION PLAN for BLACK SIGATOKA Mycosphaerella fijiensis (Morelet) SAINT LUCIA DECEMBER 2006

4 MISCELLANEOUS PUBLICATIONS ISSN CaRC/LC December 2006 Castries, Saint Lucia The views expressed in articles are those of the authors and do not necessarily reflect those of the Inter-American Institute for Cooperation on Agriculture (IICA). Mention of a proprietary product or commercial firm does not necessarily imply endorsement by the Inter-American Institute for Cooperation on Agriculture (IICA) or the authors of any paper.

5 TABLE OF CONTENTS Acronyms.. Acknowledgement i ii 1.0 GENERAL INFORMATION Preface Background Disease Assessment Disease Dissemination Life Cycle SURVEY PROCEDURES Detection Survey Method Monitoring/Evaluation Survey Delimiting Survey Orientation of Survey Personnel Survey Records REGULATORY PROCEDURES Instructions to Officers Regulated Articles Quarantine Actions Regulated Establishment Inspection Use of Authorized Pesticides Approved Regulatory Treatments Principle Activities Orientation of Regulatory Personnel Regulatory Records ERADICATION AND MANAGEMENT PROCEDURES Recommended Pesticides Approved Treatments Eradication Management Orientation of Eradication/Control Personnel Eradication and Management Records Fungicide Tolerance Monitoring PUBLIC AWARENESS AND SENSITIZATION REFERENCES.. 15 APPENDICES 17 Appendix I 18 Appendix II.. 19 Appendix III. 20 Appendix IV. 22

6 LIST OF ACRONYMS BPDTC Banana Pests and Disease Technical Committee CARICOM Caribbean Community CSME EAPDC EAP EPTF GIS GPS WINBAN YLS CARICOM Single Market Economy Emergency Agricultural Pest and Disease Committee Emergency Action Plan Emergency Pest and Disease Task Force Geographical Information System Global Positioning System Windward Islands Banana Growers Association Youngest Leaf Spotted i

7 ACKNOWLEDGEMENTS This Action Plan was developed at the request of the Banana Pests and Diseases Technical Committee (BPDTC). The members provided much support and input in its production. The members are as follows: Ministry of Agriculture, Forestry and Fisheries Mrs Joan John Norville Mr Rufus Leandre Mrs Nymphia Edwards-James Agricultural Consultancy and Technical Services Ltd Mrs Luvette Thomas-Louisy Mr Thomas St Hill Caribbean Agricultural Research and Development Institute Mr Ronald Pilgrim Windward Islands Banana Development and Exporting Company Mr Davidson Lloyd Banana Emergency Recovery Unit Mr Hilary La Force Mr Lucius Alexander Pest Services Management Limited Mr John Mederick FDL Pest Control Solutions Mr Christopher Lubin Special thanks to Ms Una May Gordon, IICA Representative in the Eastern Caribbean States, for her encouragement and for reviewing the document. Thanks also to Mrs Deborah Biscombe for putting the document in this format. Everton Ambrose December 2006 ii

8 1.0 GENERAL INFORMATION 1.1 Preface The information contained in this document is intended for use when black Sigatoka infection is imminent or known to be present. This Action Plan is to be used as guidance in implementing preventative or eradication procedures, or in managing the disease. It provides technical and general information needed to implement any phase of a black Sigatoka prevention, eradication and management programme. Specific programme actions are based on information available at that time. This plan is to be used in conjunction with the general Emergency Action Plan for Agricultural Pests and Diseases (EAP) in Saint Lucia. The EAP makes provisions for an Emergency Agricultural Pest and Disease Committee (EAPDC) chaired by the Minister for Agriculture or the Permanent Secretary. The EAPDC is responsible for the administration of the EAP. The EAPDC establishes an Emergency Pest and Disease Task Force (EPTF) with the Director of Agricultural Services as the Task Force Coordinator. The EPTF is the technical operations committee and is responsible for all technical activities to be undertaken. It consists of the Field Component, Public Education and Information Services Component, Security Component, Quarantine Component and Diagnostic Component. 1.2 Background Black Sigatoka (Mycosphaerella fijiensis Morelet) also known as black leaf streak, is a much more virulent relative of the common yellow leafspot disease (Mycosphaerella musicola Leach). The black Sigatoka fungus is known to develop much more rapidly and the time from infection of the leaf tissue to the appearance of spotting may be about 8-10 days earlier compared to yellow Sigatoka (Young and Conie 2001). Also, the organism produces spores earlier and more abundant formation of ascospores than yellow Sigatoka. Thus, black Sigatoka has a much greater infection potential and control must be geared to cope with the short interval between infection of the leaf and production of spores capable of infecting new leaves. Black Sigatoka is known to be present in West Africa, the Pacific and the Far East. In the Western Hemisphere, it has been reported in Mexico, Guatemala, Belize, El Salvador, Honduras, 1

9 Nicaragua, Costa Rica, Ecuador, Panama, Brazil, Colombia, Venezuela, Bahamas, South Florida, Cuba, Dominican Republic, Haiti, Jamaica and Trinidad. Besides banana, black Sigatoka is known to attack plantain. The available method of control is through the use of fungicides and or fungistats in conjunction with cultural control and other agronomic practices. These include optimum crop nutrition, control of root and corm pests, adequate plant density, weed management, proper drainage and reduction of fungal inoculum (detrashing and removal of infected leaves). Since black Sigatoka is more virulent and aggressive than yellow Sigatoka more frequent fungicide applications are required. Intervals between applications vary from 7-21 days but in areas of higher disease potential, spraying every 7-10 days in the year may be necessary. In Jamaica, the 29 fungicide applications initially used were decreased to in various locations according to rainfall and evaporation levels when climatic and biological disease forecasting strategies were utilized (Conie 2001a). Frequent applications of straight-oil as a carrier of the fungicides would cause considerable phytotoxic damage, therefore, oil-water emulsion (with emulsifier) has to be employed as additional carrier for fungicides to minimize phytotoxic injury. Cost to the farmer for black Sigatoka chemical control reported for Jamaica ranged from US$ /ha/year for estates to US$ /ha/year for small farms, 17-18% of the total production cost. Centrally managed control cost for small farms is US$ /ha/year, 8.4% of total production cost (Conie 2001a). The fungicides currently in use are propiconazole, benomyl, azoxystrobin and tridemorph. The extensive use of these fungicides at short intervals could undoubtedly lead to the development of tolerant fungal strains. To reduce this risk, applications of different fungicides are alternated. 1.3 Disease Assessment Disease Assessment monitors the level of the disease in a given area using a method which measures the disease incidence at any given time. The information is useful in providing a basis for an efficient control programme. Cronshaw (1982) suggested dividing the banana lands into 2

10 geographical areas with similar conditions viz. climate, accessibility of spraying, drainage etc, and within each of these areas, a number of representative fields chosen as reference points. The reference points can be assessed by two methods, the youngest leaf spotted and the Cronshaw Methods. In the youngest leaf spotted (YLS), twenty-five (25) mature unshot plants per acre are assessed every 14 days. The youngest fully opened leaf with ten (10) or more spots is recorded. This method only takes into account the advanced stages of the disease (spot stage), which are easily visible. However, with this method, the disease has already caused leaf damage. The format for recording is given in Appendix I. The Cronshaw method assesses the early stage of the disease and hence preventative measures can be taken. In this method ten (10) young plants/followers are assessed per acre weekly and the most advanced stage of the disease with 10 or more spots on the first five (5) leaves of each selected plant is recorded. The format for recording is given in Appendix II. In addition to the use of biological data, assessment can be made utilizing climatic data. The use of evaporation data, which indicates moisture/humidity conditions of the atmosphere has been shown to be useful in helping to decide when conducive for leafspot development and therefore to make predictions on the time for spraying. Details on the use of the method are given in Appendix III. 1.4 Disease Dissemination Fungal spores can move very short distances on their own power and thus move from one host to another one very close to it. The hyphae can grow between tissues in contact. However, both of these modes of dissemination are very limited. Almost all dissemination of fungal pathogens responsible for disease outbreaks and even disease occurrences of minor importance are carried out passively by agents such as air, water, insects and other animals and human beings. 3

11 Air Air currents carry fungal spores as inert particles to various distances. Spores are picked up from the structure on which they are borne or while they are being forcibly expelled or are falling at maturity and, depending on the air turbulence and speed, may carry the spores upward or horizontal in a way similar to that of particles contained in smoke. While air borne, some of the spores may touch wet surfaces and get trapped, and when air movement stops or when it rains the rest of the spores land or are brought down by the raindrops. Most of the spores though, land on anything but a susceptible host plant and are therefore wasted. The spores of many fungi are actually too delicate to survive a long trip through the air and are successfully disseminated for only a few hundred or thousand meters. Wind also helps in dissemination of spores by blowing away rain splash droplets containing these and wind carries away insects that may contain or are smeared with spores. Water Spores may be washed downwards or splashed in all directions by rain or overhead irrigation water. Raindrops or drops from overhead irrigation pick up the fungal spores present in the air and wash the downwards where some may land on susceptible plants. Insects, mites, birds and other vectors Each one of these vectors can transmit spores in a plantation or between plantations during feeding and movement from plant to plant. Depending on the kind of vector and the prevailing weather conditions, the spores may be transmitted over short or long distances. Almost all animals that move among plants and touch the plants along the way, can disseminate the spores. The spores adhere to the body of the animals or are carried in the contaminated mouthparts. Human beings Human beings disseminate spores over short and long distances in a number of ways. Within a field, through successive handling of diseased and healthy plants. Human beings also disseminate spores on infected planting materials through a field from field to field or from country to country. Spores may also be transported from country to country by human beings 4

12 adhered to their clothes after visiting an infected field, or in an article which is contaminated with the spores. This disease is transmitted primarily by wind. However, given the present distribution of black Sigatoka, the risk of wind dissemination of the fungus from the infected areas appears to be low. Airborne dispersal from Central or South America, Jamaica, Haiti, Cuba, Dominican Republic, South Florida and Trinidad to Saint Lucia, seems unlikely since the prevailing winds in the Caribbean Basin are easterly. However, there are occasions when the weather pattern alters and the wind direction changes from west to east around the Caribbean Sea, thus increasing the risk of transmission from infected areas around the Caribbean Sea. Black Sigatoka also occurs in parts of West Africa and this raises the question as to whether spores could be carried to the Caribbean in the easterly transatlantic trade winds. However, there is doubt as to whether these thin-walled, hyaline spores would survive the low temperatures, desiccation and ultra violet radiation to which they would be subjected at altitudes of feet during the long period (12-13 days) required to cross the Atlantic (Lawrence 1987). Parnell et al (1998) studied the influence of exposure to ultra violet radiation in simulated sunlight on ascospores causing black Sigatoka disease and concluded that wind dispersal of viable spores over distances greater than a few hundred kilometres is unlikely. These conclusions are reinforced by an examination of historical reports of the arrival of the disease in previously uninfected areas of the Americas and Africa. However, the possibility should not be entirely discounted. Dissemination by human beings, therefore seems the most likely means by which the disease can be transmitted to the country. The disease is presently in Trinidad, and, with rapid modern air transport and increased trade with the CARICOM Single Market and Economy (CSME) imminent, could be introduced by travellers on aircraft following a visit to black Sigatoka infected banana fields in Trinidad, Jamaica or elsewhere, since spores on clothing can survive the journey. Additionally, there is the uncontrolled yacht trade, where infected Musa leaf material and plants could be carried by these travellers. Other plant species and non-plant materials collected from black Sigatoka infected areas may also passively bear viable spores. 5

13 15 Life Cycle The same conditions required for optimum plant growth are also conducive for development of black Sigatoka. The disease does not develop well under cool conditions or areas of high elevations. Shading can reduce symptoms expression. Visual field symptoms may suggest differences between yellow and black Sigatoka but are not sufficiently distinctive to separate the two diseases (Appendix IV). The stages of development of the disease Conie (2001b) are as follows: Stage 1: A small yellow speck visible only on the underside of the leaf Stage 2: Brown streak visible on the underside of the leaf. Later appears on the upper surface as a yellow streak, which progressively turns brown Stage 3: Streak gets longer, wider and very dark brown in colour. In certain conditions (weak inocula and unfavourable climatic conditions) can reach 2-3 cm Stage 4: Appears on the underside as a brown spot and on the upper side as black spot. The elliptical spot is black on the upper side of the leaf and is surrounded by a yellow halo with the centre beginning to flatten out Stage 5: The centre of the spot dries out, turns grey and is surrounded by a well-defined black ring which is in turn surrounded by a bright yellow halo 2.0 SURVEY PROCEDURES In order to determine the status of the disease in an area, a survey must be conducted. The survey provides information on the presence or absence of the disease and the level of infection if it is present in an area. The information obtained will guide decision-making on whether any action should be taken, the type of action, and extent of the action to be taken. 2.1 Detection Survey Detection survey is done to determine whether the disease is present in an area and the levels at which it is present. Management strategies can be selected based on the disease level. Continuous surveys using the Cronshaw method should be undertaken at the normal yellow Sigatoka reference points. In addition, if black Sigatoka disease is found in an area, weekly 6

14 surveys should be undertaken in areas up to 10 miles (4 Km) from the epicentre. All detections must be confirmed in the laboratory. A visual survey of 10 acres (4 ha) of bananas will be continued in the area for at least two months after the last find. In addition, the Task Force Coordinator should request farmers, extension officers, other field personnel and members of the public to look out for the disease in the course of their regular work particularly in the 10 miles (4 Km) of the infected area, especially after storms or other atmospheric disturbances. A hotline facility must be set up for reports of unusual leaf symptoms by the public. All suspected findings must be investigated and preliminary results confirmed by a recognized laboratory. Since the disease is not present then the whole country should be surveyed as a precautionary measure to determine presence or absence. All unusual findings should be guided by laboratory confirmation. Plantains may be used as indicator plants but constant monitoring of the plants is necessary Method Using the site of detection as the focal point (epicentre), locate suitable plants in at least each 25 square miles or ten square kilometres, (Km 2 ) of the core area. Up to twenty-five (25) acres (10 ha) of host if available, are to be surveyed in the core area using the Cronshaw method of assessment. This will include 5 miles in each 25 square miles or Km 2 around the epicentre where the finding was made or other nearest suitable plants followed by monitoring/evaluation surveys carried at weekly intervals. 2.2 Monitoring/Evaluation Survey Monitoring/evaluation surveys are conducted in the area where control/eradication treatments are applied to assess the level of disease infection at the particular period and to determine the time of application of a treatment. The Cronshaw and YLS methods are utilized in these areas. 2.3 Delimiting Survey Delimiting survey is used to determine the distribution of the disease in an area. The delimiting survey relies mainly on the visual inspection for symptoms of the disease. The disease can be seen through all the stages of development. However, the delimiting survey 7

15 should be undertaken for Stages 1 and 2. The visual inspection should be guided by a laboratory confirmation. 2.4 Orientation of Survey Personnel New personnel should be trained on the job in all aspects of disease identification, survey and management. It will be necessary to have at least one week (5 working days) to teach personnel the many facets of the black Sigatoka disease. 2.5 Survey Records Records noting the areas surveyed, dates, location, Musa plant types, age in which detections were made should be maintained and be centrally managed by the Task Force Coordinator. 3.0 REGULATORY PROCEDURES 3.1 Instructions to Officers Regulatory actions are required until the disease is eradicated or no longer of quarantine importance. Any material including those of plant or Musa spp to be removed from infected fields must be treated. Only authorized treatment procedures should be used. 3.2 Regulated Articles Any above ground pest of the Musa species or any plant, product, article or means of conveyance of any character determined by an inspector to represent a hazard of spread of black Sigatoka must be confiscated and destroyed, or detained, treated and released. Persons who have visited infected fields either in Saint Lucia if the disease is present or outside of Saint Lucia also present a risk of dissemination of the disease. All persons entering Saint Lucia must present a signed Customs Declaration Form to the Customs Officer on duty. This form will indicate whether the person is carrying regulated articles or has visited an infected farm within 24 hours. A protocol to facilitate trade with infected countries must be developed for each country. 8

16 3.3 Quarantine Actions When detections have been made, the following steps should be implemented in sequence. With the detection site considered the epicentre, all growers and establishments that grow, handle, move or process regulated articles within a minimum of three (3) miles (1 Km) will be issued emergency action notifications requiring treatment or other approved handling procedures. Emergency Action Notification and/or comparable notifications should be issued by field personnel to property owners or managers of all establishments who grow, handle, move, or process articles capable of spreading black Sigatoka. A notification is issued pending authoritative confirmation and/or further instructions from the Task Force Coordinator. If necessary, the Task Force Coordinator would issue a letter directing the appropriate Emergency Action Plan Component(s) to initiate specific emergency action under the Plant Protection Act until regulations announcing emergency action can be published. The Plant Protection Act provides authority for emergency regulatory action. The Task Force Coordinator through the Information and Field Components will notify the public of the actions taken and actions contemplated. A narrative description of the regulated area with support documents will be developed by the Task Force Coordinator and co-operators and provided to the Quarantine Field Component. The regulated area will also be defined by Geographical Information System/Global Positioning System (GIS/GPS) for use by the Task Force Coordinator and the National Emergency Pest and Disease Committee. 3.4 Regulated Establishments Inspection Efforts to detect the disease within the regulated area should be made at all establishments where regulated articles are grown, handled, moved or processed. Establishments that might be involved are: airports, seaports, landfill sites, processing plants, farmers markets, produce markets, nurseries, farms, laboratory facilities, hotels, restaurants and other establishments that handle regulated articles. At these premises, a visual examination of host material and containers will be necessary together with samples for laboratory examination to detect and/or confirm the presence of damage and spores. 9

17 3.5 Use of Authorized Pesticides This Action Plan contains chemicals authorized by the Pesticides and Toxic Chemicals Control Board, methods and rates of application, and any specific application instructions. 3.6 Approved Regulatory Treatments a) Washing: Use running water to hose down vehicles and other suitable articles before leaving infected farms or premises. Attention must be given to the proper disposal of wastewater. b) Clothing Disposal: Personnel working and visiting infected farms and premises are required to wear disposable paper coveralls and plastic shoe covers. Any clothing worn should be place securely in plastic bag before leaving the farm or premises and disposed of, by burning, in a landfill or washed as soon as possible. c) Planting Material: Planting material should be treated with the appropriate pesticides. d) Sanitation: Removal and destruction of leaves, fruits and other host material found during operations from premises, farm establishments, and vehicles handling regulated articles e) Processing Waste: Proper disposal of waste material from processing plants in plastic bags or other suitable containers to approved landfills or treatment by approved measures 3.7 Principal Activities The following identifies the principal activities necessary for implementing a regulatory programme to prevent the entry and spread of black Sigatoka: Advising the Quarantine Division of the quarantine measures at the ports of entry confiscation, treatment procedures Supervising, monitoring and certifying treatments Risk assessment country, passenger, materials and equipment Record keeping results of surveys, results of risk assessments Awareness, sensitisation, and surveillance of the following potential sources of dissemination: 10

18 Security, airline and shipping personnel, customs, port authority and related personnel Farmers, packers, processing plant operators and related personnel Supermarkets and other distributors Cruise ships, aircrafts, hotels, restaurants, shipping agents, cargo ships, yachts, fishing boats Commercial haulers of regulated articles Public transportation General public, importers, other countries, exporters, quarantine personnel, Customs Monitoring the movement of waste material to and from landfills to ensure adequate disposal of regulated articles and refuse Monitoring the movement of host material along major high ways and across quarantine boundaries 3.8 Orientation of Regulatory Personnel Only personnel that are trained or experienced in plant quarantine and black Sigatoka disease management should be used initially. Replacement personnel should be trained by the individuals being replaced. A training period of at least five working days is necessary for the orderly transfer of these functions. 3.9 Regulatory Records Records should be maintained, as necessary, to carry out an effective programme. 4. ERADICATION AND MANAGEMENT PROCEDURES Eradication of black Sigatoka infection is the desired goal. Thus early detection and rapid action is critical. The earlier the detection the more likely are the chances of eradication, otherwise the next best option remains management of the disease. Risk assessments will have to be undertaken periodically. 11

19 4.1 Recommended Pesticides Protectant or contact fungicides (dithiocarbamates and chlorothalonil) have multi-site action in controlling the fungus. These can only be applied in water or in emulsions. Dithiocarbamates are applied at g/ha and chlorothalonil is applied at g/ha. Dithiocarbamates: Chlorothalnil: Mancozeb 1.5 lb/ac Chlorothalnil l/ac. Systemic fungicides are absorbed by the plant and can kill the fungus within the leaf after infection. They have specific modes of action. Benzimidazoles: benomyl 4 oz/ac Morpholines: tridemorph 200 ml/ac fenpropimorph Triazoles or Demethylation Inhibitors (DMI) Strobilurins: propiconazole 160 ml/ac flusilazole fenbuconazole bitertanol tebuconazole cyproconazole epoxyconazole azoxystrobin 160 ml/ac tefloxystrobin Triton x 45 (emulsifier) 50 ml/ac. Mineral oil: 1-2 gal/ac 12

20 4.2 Approved Treatments Eradication If the very first few plants that are infected are detected before the formation of spore producing spots, the chance of eradication though slim is likely. The infected field should be cordoned off and all movement of unauthorized personnel in or out of the area prohibited or controlled. The leaves of infected plants should be destroyed completely and as quickly as possible using such means as drenching them with diesel oil and burning. The rest of the field should then be cut down, including all followers (suckers) and leaves. Depending upon the locality, all neighbouring fields especially those downwind will also have to be cut back and all leaf material destroyed. Unfortunately, by the time the presence of the disease is suspected and confirmed, spots probably would already have been formed and spores liberated in the air to be dispersed over long distances by the wind. If the disease arrives by natural means (wind) numerous infections are likely to occur scattered over a wide area, too difficult to deal with in the manner suggested above. In such a situation considering the location of the farm, the best option would be to put in a programme for managing the disease Management a) Application of Fungicide Application of fungicide based on disease forecasting system. The choice is one which is based upon regular assessment of evaporation and early infection stages of disease. b) Additional Materials and Equipment Adequate stocks of materials and equipment (fungicides, oil emulsifier, fuel, mist blower and accessories) required should be available immediately following first identification of the disease. Since the quantity of material routinely required for spraying operations would be greatly increased, it would be necessary to re-compute quantities to ensure regular supply of these materials so that adequate stock would be constantly maintained. Contacts/list of/sources/suppliers of black Sigatoka control inputs should be available as well as protocols for immediate requisition of materials. 13

21 c) Supplemental Methods i) Crop hygiene cultural practices (pruning of unwanted suckers, weed control, adequate drainage and detrashing) must be carried out vigorously and strictly enforced. Severe tip spotting and leaves with 50% or more of their area affected should be cut off weekly. Fruiting plants with less than five healthy leaves and with several weeks remaining before harvest should be cut down. ii) Removal of land from banana production. Any area which cannot be effectively sprayed should be removed from production. Plants from all abandoned fields must be cut down. Persons not in commercial production should be encouraged to plant black Sigatoka resistant varieties. 4.3 Orientation of Eradication/Management Personnel Only personnel trained and experienced in disease identification and management should be utilized initially. Replacement personnel should be trained by the individual being replaced. A period of at least 5 working days is necessary for the orderly transfer of these functions. 4.4 Eradication and Management Records Records noting the locations of detection, dates, number and type of activities and materials used should be maintained for all treated areas and centrally managed by the Task Force Coordinator. 4.5 Fungicide Tolerance Monitoring An effective monitoring programme should be maintained to aid in the evaluation of control programme efforts and environmental impact. The application and use of fungicides and other controlled substances should be assessed throughout using the appropriate monitoring programme criteria. The evaluation must effectively address agency, co-operator and public concerns. The monitoring programme should include at least: 14

22 i) Determine efficacy of the fungicide used Fungicide sensitivity Disease levels in the treated areas Environmental impact of chemicals used 5. PUBLIC AWARENESS AND SENSITIZATION The success of the plan would depend on the voluntary support, cooperation and understanding of the various stakeholders: General public Farmers Extension officers Students News media Commercial interest Technicians Public awareness and sensitisation activities should be initiated immediately. 6. REFERENCES Conie, J (2001a), Overview of Black Sigatoka Disease in Jamaica Caribbean. IICA (2001) Report on Caribbean Black Sigatoka Management Workshop, Kingston, L Thomas- Louisy, Edit 116 pp. Conie, J (2001b), The Effects and Symptoms of Black and Yellow Sigatoka Disease on Banana and Plantain. IICA (2001) Report on Caribbean Black Sigatoka Management Workshop, Kingston, L Thomas-Louisy, Edit 116 pp. Cronshaw, D.K. (1982) Management of Banana Leafspot (Sigatoka) Disease in the Windward Islands Tropical Pest Management, Vol. 28, No Lawrence, J.S (1987) Black Sigatoka Disease of Bananas; Contingency Plans for its Control in the Windward Islands and Implications for the Regional Banana Industry, WINBAN. 18 pp. Ministry of Agriculture, Forestry and Fisheries (2004) Emergency Action Plan for Agricultural Pests and Diseases in Saint Lucia 24 pp. 15

23 Parnell, M, Burt, P.J.A. and Wilson, K. (1998) The Influence of Exposure to Ultraviolet Radiation in Simulated Sunlight on Ascospores causing Black Sigatoka Disease of Bananas and Plantain (Abstract). hb USDA/APHIS/PPQ (1983) Action Plan Format Young, M. and Conie, J. (2001) Life Cycle of (Mycosphaerella fijiensis) and Epidemiology of Black Sigatoka Diseases in IICA (2001) Report on Caribbean Black Sigatoka Management Workshop, Kingston, L Thomas-Louisy, Edit, 116 pp. 16

24 17

25 APPENDIX I FORMAT FOR RECORDING YOUNGEST LEAF SPOTTED (YLS) FARM: DATE:. TECHNICIAN: Plant No TOTAL Average YLS LEAF NO Leaves Spotted 18

26 APPENDIX II FORMAT FOR RECORDING THE CRONSHAW METHOD OF ASSESSMENT (CRONSHAW 1982) Summary Leaf Number Multiplication Factor x most advanced spot stage of 3 3 which there are more than present 5 1 TOTAL Data Sheet used to monitor early infection stage of Leaf spot Plant Leaf Number No I II III IV V Totals X = 19

27 APPENDIX III ASSESSMENT BASED ON EVAPORATION Evaporation is measured using a Piche evaporimeter tube fitted with 3 cm diameter filter paper disc and hung in wooden shelter below. Fig 1: Diagram of simplified Piche shelter (Cronshaw 1982) The total evaporation per week is recorded and an average calculated from the previous week s total. If: E 1 is the evaporation total of the first week after an application E 2 is the evaporation total of the second week after an application E n is the evaporation total of the nth week after an application Then the weighted average for the second week is: EW 2 = E 1 + E 2 2 and the weighted average for the nth week is: EW n = E n + EW (n-1) 2 20

28 The tube should never be allowed to run dry. In order to have a forecasting system it is necessary to know how the EW values relate to time intervals between spray applicators. By comparing the data readings from the three open valleys and eight locations in undulating terrain with what experience has shown to be the necessary spray cycles over a period of up to three years as determined by Stover and Dickson (1970) and in Cronshaw (1982) foliar disease assessments, it was possible to arrive at two relationships between EW and spray intervals. Flat open valleys d = EW/6 and for undulating terrain d = EW/4 where d = the time interval in weeks between applicators of oil and systemic fungicide. The locations of the instruments covered most of the main growing areas from which the two relationships were derived. 21

29 APPENDIX IV SYMPTOMS (VISUAL) DIFFERENCES BETWEEN YELLOW SIGATOKA AND BLACK SIGATOKA Yellow Sigatoka often has a pattern of line spotting caused by conidia and tip spotting caused by ascospores. This is not observed with black Sigatoka where spotting is distributed all over the leaf surface. Black Sigatoka forms mass lesions closer to the mid rib than yellow Sigatoka particularly in sprayed bananas. The initial observable symptom is a pale yellow speck on the upper surface with yellow Sigatoka. The yellow speck lengthens into a yellow streak and then gradually widens, lengthens and turns a mottled rusty-brown colour. With black Sigatoka, the initial symptom is a reddish-brown speck on the lower surface of the leaf. The reddish-brown speck lengthens into a reddish-brown streak and then goes to dark brown or black and is now visible on the upper surface. Later spot stages are similar but mass black Sigatoka spotting tends to have a darker appearance and is more widespread on the leaf closer to the mid vein. 22

30 Spores usually germinate within 2-3 hours of deposition on the moist leaf surface of the host. The germ tube penetrates through the stomata after hours at temperatures above 20oC. All leaves are equally susceptible, however, most infections occur on new leaves between emergence and unfurling. Under ideal conditions the time between infection and appearance of the first speck symptoms on the leaf is days. Black Sigatoka on upper surface of leaf Black Sigatoka on upper surface of leaf Advanced symptoms of Yellow Sigatoka Black Sigatoka typical symptoms Yellow Sigatoka Black Sigatoka lower surface of leaf 23

31 INTER-AMERICAN INSTITUTE FOR COOPERATION ON AGRICUTLURE OFFICE IN SAINT LUCIA 4 TH Floor, Sir Stanislaus Anthony James Building, Waterfront, Castries Saint Lucia, P O Box 1223 Tel: 1 (758) /61 Fax: 1 (758) iica.lc@iica.int Website: