GOOD AGRICULTURAL PRACTICES (IPM) TRAINING WORKSHOP. 7 May 2014

Transcription

1 GOOD AGRICULTURAL PRACTICES (IPM) TRAINING WORKSHOP 7 May 2014

2 Diseases - General The study of diseases consists of: how the pathogen affects the plant the reaction of the plant to the disease the spread of the disease effect of the environment on the development of the disease how to manage the disease to reduce its impact

3 Diseases - General 120 diseases reported on sugar cane but most of them are of minor importance Note: a disease can be a minor one but later become a major one or it can be minor in one country but major in another There are some however which are important Major sugarcane diseases in Mauritius Bacteria Fungus Gumming, Leaf scald Yellow Spot, Rust, Smut

4 Diseases - General Disease epidemics in noble canes have threatened cane industries in the past e.g. - gumming in Mauritius -mosaic in US - root rot in Hawaii Major progress achieved with the development of hybrid issuing from crosses with wild canes adding to resistance to diseases.

5 Diseases - General Factors favouring epidemics 1. introduction of new disease in a region 2. Occurrence of new disease strains 3. Increase of inoculum due to the planting of susceptible varieties on a large scale 4. Exceptional weather conditions favouring infection and spread of the disease and vectors

6 Transmission of diseases Incidence, severity and distribution of a disease depend on the mode of transmission and spread pathogens are transmitted by different means presence of susceptible hosts and the stage of development of the cane are essential (e.g. rust will develop on young canes)

7 Transmission Insect vectors Wind Sources of diseases Infected cuttings Crop residues left in situ Secondary host plants Inoculum in soil Infected fields Vectors Cultural operations Water Agents of dissemination MAN

8 INSECTS and AGRICULTURE 1/4 of world harvest destroyed every year by insects in the fields or in stores!! 2/3 of plants on earth would not have existed without insects!! some insects are pests More than species are considered as pests worldwide fortunately this wide array of pests also has a wide range of natural enemies! insects can be beneficial, e.g. pollinators, entomophagous.

9 Insect pests are those which: 1. Destroy or damage all kinds of crops and other valuable plants directly or indirectly 2. Annoy or injure man and other animals 3. Vector of diseases 4. Damage stored products

10 Insects can Feed on leaves, flowers, flower buds, fruits,seeds

11 Insects can Bore into roots, stems, leaves, fruits

12 Insects can Suck sap

13 Insects can Chew roots and stalks

14 Insects can Cause malformation

15 Insects can Secrete toxic substances Spread pathogens

16 Extent of damage depends on: Insect population (in space and time) Crop and varieties Part of plant which is injured Stage of the crop Plant vigour

17 How do pest populations arise? 1. Effects of monoculture Reduction in natural enemy and competitor populations Easier host location Microclimate change 2. Pesticides/ toxic chemicals 3. Introduction of new species of plants and animals 4. Plant breeding

18 Distribution and origins of sugar cane pests 1300 species recorded Varies from one region to the other, except for some species, e.g the pink mealybug Saccharicoccus sacchari Insect pest problems in sugar cane are more of a regional nature Dual origin: local species adapted to sugar cane versus exotic species How new species enter a country? Why should we know the origins of a pest?

19 Integrated Pest Management Promoted during 1960s after problems with insecticides (in cotton production) IPM philosophy Integrating options to limit economic crop damage, non-target effects, environmental damage & adverse effects on consumers Less emphasis on insecticides & more on suitable alternatives Complex to implement & requires knowledge of population processes & environmental factors that regulate pest populations

20 Basic of IPM CORRECT PROBLEM DIAGNOSIS Why? 1. Knowledge of biology and behaviour of pest 2. To know the effect of the insect/pathogens 3. For a new introduction to know if natural enemies exist

21 Integrated pest management Levels of IPM variable Preliminary = monitoring pest levels & timing insecticide sprays Advanced = conserving long-term health & productivity of ecosystems; organic farming

22 Approaches to IPM Prevention Action taken to prevent anticipated pest problem Pre-planting insecticide applications; destroying future sources of infestation; conserving natural enemies etc Suppression Action taken to suppress detected pest problem Reduce pest densities to below threshold levels Chemical methods are often used (quick action) Eradication Action taken to totally eliminate detected pest problem Widespread actions to eliminate new pests before they become established & widespread Chemical control is main tool

23 Approaches to IPM Control measures can classified in various ways: Cultural Resistant varieties Biological control Chemical control Interference methods Legislative measures Other methods

24 Cultural control Tactics to pest populations Early harvesting (prefer older cane) Cutting plants at ground level (no stalks for caterpillars) Burning crop residues so re-growing plants are not reinfested Applying reduced levels of nitrogen Habitat management ( push-pull system) Attractant plants (papyrus, giant water grass) Repellent plants (silver-leaf desmodium, vetiver)

25 Cultural control Several cultivation techniques used to control insect & other pests (crop rotation, intercropping etc) Additional techniques used against insects: Physical removal Hand picking or spraying with water Only for small scale operations Adhesive barriers Sticky bands applied to base of trees (citrus & fruit orchards) Tangle walking insects (e.g. ants) Non-toxic traps Capture flying insects (attraction-annihilation) Yellow sticky traps; pheromone & UV traps used with electrocuter grids Effective in tunnel situations

26 Cultural control Artificially produced sound Disrupt flying insects that use sound communication Attract insects into traps or repel them Used in intensive greenhouse systems Regulating moisture levels High moisture levels (e.g. overhead sprinklers) Stored products need to be kept very dry (below insect s critical RH) Regulating temperatures Stored products treated with lethal temperatures (high or low) Heat & smoke treatment to protect stored grain

27 Cultural control Application of non-toxic dusts Wood ash/ fine dust mixed with stored grain Dusts destroys waterproofing properties of insect cuticle & ruptures inter-segmetal membranes Insects die from water loss Habitat management ( push-pull system) Planting of attractant & repellent plants in croplands Attractants are preferred hosts which pull insects & natural enemies into croplands & off crops Repellents produce volatile chemicals which push insects away from crops

28 Plant Resistance - Susceptible: varieties which show average of more than average damage by a pest - Highly susceptible: varieties which are readily infested and suffer above average damage

29 Mechanism of Plant Resistance Tolerance crop is capable of supporting population of pest without loss of vigour Antibiosis crops have adverse effects on the pest (nitrogen poisoning) Preference and non-preference crop influences the behaviour of the pest forcing it onto another plant (odours and trichomes)

30 Plant Resistance Making a crop resistant to a pest must not make it susceptible to another. Development of multiple resistance, high yield potential and consumer acceptance is the ultimate aim.

31 Components of HPR programme 1. Personnel -- Multidisciplinary team 2. Pest biology -- Influence of biotic and abiotic factors, Behaviour, oviposition, movement, fecundity, growth, feeding habits, effect of environment on population 3. Pest population -- Availability of a constant and uniform insect population 4. Genetic sources -- Search for adapted cultivars, Plant introductions/ exotic germplasm, Near relatives of cultivars, Identifying sources and assay techniques 5. Levels -- How small an increment is usable in the development of HPR? Primary consideration given to: The effort necessary to bring the source to commercial cultivation Interaction within a total pest management programme

32 Plant factors Effect(s) on insect Thickening of cell walls; increased toughness of tissues Interference with feeding and oviposition mechanisms Trichomes Accumulation of surface waxes Incorporation of silica Effect on feeding, oviposition, locomotion and attractiveness; toxic and disruptive effects of allelochemicals in glandular trichomes Effect on colonization and oviposition Abrasion of cuticle; feeding inhibition

33 Biological Control Use of parasitoid, predator, pathogen, antagonist, or competitor populations to reduce the populations of a pest Principal biological control methods Conservation Conservation to make an environment more attractive to natural enemies Augmentation In cases where the populations of natural enemies are too low or late to build up, their numbers can be increased. Introduction of new natural enemies into the environment The most frequent way of applying "biological control". Objective: permanent decrease in the pest population by the establishment in the environment of a new factor adverse to the pest.

34 Groups of natural enemies: Predators Parasitoids Pathogens Bacteria Fungi Viruses Protozoa Nematodes

35 Procedure for undertaking a biological control programme 1. Evaluation - Extent of the problem, Nature and amount of damage, Value of loss incurred, Cost to the nation/ farmer, Social and political factors 2. Preliminary studies - Identify pest, Literature, Origin of pest, Pest biology, Natural enemies 3. Project proposal - Seek funding 4. Surveys and exploration - In areas where the pest is a problem, In area of origin of pest 5. Biological studies and agent selection - Agent should be host specific 6. Screening - Agents should not pose a risk to agriculture and/or the environment 7. Quarantine 8. Shipping - Stage, No organic matter in packing, Moisture/ food, Shipping route as short as possible 9. Production and release 10.Evaluation 11.Documentation

36 Problems related to abuse of insecticides Development of insecticide resistance Pest resurgence Secondary pest outbreaks Solution: Use less toxic chemicals e.g botanical pesticides Biological control

37 Insecticidal Control Quick remedy to insect attack on a crop. Grower himself can apply Drawbacks: (a) never offers a permanent or a lasting solution to a pest problem. (b) may become less effective in time because of the development of resistant strains of the pest. (c) Costs may be considerable and are recurrent. (d) Destruction of beneficial insects (e) Crop produce is liable to contamination by residues. (f) There may be hazards to those applying insecticides. (g) Organisms other than insects may be affected (run off into streams may kill fish, birds may die from eating poisoned insects or insecticide-treated seeds).

38 Maxims to remember concerning insecticides are: (a) Never apply insecticides unnecessarily. (b) Never apply insecticides liberally: do not exceed recommended doses or disregard recommended application intervals. In other words, apply the principle of minimum insecticides usage, and (c) Never regard insecticides as the most desirable method of pest control.

39 5 Legislative Measures Legislation concerning pests and diseases enables the enforcement of measures to: (a) Reduce the chances of new pests and diseases entering a country (b) Control pests and diseases already present in a country

40 Components of Biosecurity Plan Reducing the risk posed by exotic organisms to the sugar industry through exclusion, eradication and control. PRE-BORDER identifying exotic pest threats. managing quarantine risks offshore. undertaking offshore research and development where pests are endemic. BORDER implementing effective quarantine for people, machinery, plants, and goods. establishing trapping and surveillance networks for pests that may bypass checkpoints. POST-BORDER minimising risk of regional and property entry and establishment. preparing for timely detection, minimised spread and rapid response to emergency pests. Achieved through effective partnerships between industry, government and the community

41 LEGISLATION AND QUARANTINE OF SUGAR CANE LEGISLATION In Mauritius: PLANT PROTECTION ACT 2006 Requirement of an import permit Importation from authorised countries Conditions attached to the importation to be respected; Area free from the disease Inspection during active growth Hot water treatment Chemical treatment Phytosanitary certificate Quarantine on arrival for crops like sugar cane To control a disease which already exist in the country: Legislation can be used in the case of eradication of a variety owing to high susceptibility to a disease

42 Natural pathways of entry: Vectors such as fungi, insects, mites, slugs, birds, rodents and other animals Propagules transported passively by storms, air currents, wind, by ocean currents or land surface drainage Splashing (rain-generated ) Self locomotion of spores and cells Natural dispersal of infected seed

43 Man-made pathways Mail containing articles that can harbour pathogens Baggage containing fruits and vegetables Agricultural & Non agricultural cargo Cargo containers, aircraft Crates, pallets, used bagging or packing materials, Garbage Smuggling

44 USES OF PHEROMONES IN INSECT PEST MANAGEMENT 1. For determining economic thresholds 2. For simple detection and quarantine 3. Study of population movements 4. Mass trapping 5. Mating disruption

45 Physical Methods Must be based on detailed understanding of the pest s biology, behaviour and physiological requirements. Adoption depends on level of effectiveness, convenience, ease of use and economic considerations Bands Insect traps: Coloured traps, Plant materials, Fermentation traps Barriers e.g. screens, Row covers, Trenches, Particle barriers, Inert dusts, Bags, Shields, Packaging Physical disturbances e.g. shaking, jarring, mechanical disturbances, hand-destruction, Sanitation Extraction e.g. digging, vacuuming, Irrigation, Mulches e.g. cover crops, floating row crops Light traps e.g. electrocuting traps, suction light traps. Irradiation, Temperature heat / cold, Sound Controlled atmospheres e.g. CO 2,N 2

46 End of session 1