MANAJEMEN PENYAKIT TANAMAN

1. MANAJEMEN PENYAKIT TANAMAN PrinsipUtamaPengendalian

2. Penyakit Tanaman dalam Praktek

3. Prinsip Utama Pengendalian Sebelum patogen muncul • Eksklusi = usaha mencegah introduksi atau menetapnya patogen Sesudah patogen muncul • Terapi = prosedur – prosedur yang dilakukan setelah patogen muncul

4. Eksklusi Patogen 1. Karantina (Quarantine) = program ataukebijakanuntukmencegahintroduksipatogen 2. Bahantanambebaspatogenataupenyakit a. Certification of seed and other planting material b. Treatment of propagation material “Regulatory Plant Pathology” (PengendaliandenganPeraturan / UU)

5. Penghidaran dari Patogen Menghidaripenyakittanamandenganmenanam: 1. Saatinokuluminaktifatau level inokulumrendah 2. Padadaerahatau area yang tidakendemispenyakitataubebasinokulumatau yang lingkungannyamendukung. • Memproduksibenihkomersialdi area yang jauhdaridaerahendemispenyakit

6. Eradikasi Patogen • Mengurangi, mengambil, membuangataumemusnahkaninokulumpadasumbernyabaikpada area ataudariindividutanaman yang telahterserang • Rotasidengantanaman yang dapatmemutusperkembanganbiakanpatogen • Perlakuandenganbahankimia, panasdll= soil sterilization for potting mix, fumigation • Fungisidaeradikan • PengendalianHayatipatogentanaman

7. Melindungi Tanaman • Mengurangi atau menghilangkan efektivitas inokulum pada daerah infeksi dengan memberi penghalang antara tanaman dan patogen • Penyemprotan bahan kimian atau dusting daun • Perlakuan benih • Fungisida protektan

8. KetahananTanamanterhadapPatogen • Mengurangiefektivitasinokulum, denganmengurangikeberadaanpatogen Terapi/perlakuanpadatanamansakit • Mengobatiataumeminimalisasikehilanganolehtanamansakitdenganbahankimiaataumengubahkeparahandenganmemanipulasilingkunganuntukmengurangiintensitaspenyakit

10. Vanderplank’s Equivalence Theorem “Effects of host, pathogen and environment can be translated into terms of the rate parameter of an epidemic” Changes in any component has an equivalent effect on disease • More-less susceptible host All affect • More-less favorable environment amount of • More-less aggressive pathogen disease

11. Therefore, disease management principles and practices are often centered around the concept of the Disease Triangle so that management tactics often seek to manipulate one or more of the components of the disease triangle.

12. Knowing how particular pathogens go through their disease cycle is important in developing management strategies.

13. Understanding how disease cycles relate to disease severity is assisted by the discipline of Epidemiology • Epidemiology is “the study of factors affecting the outbreak and spread of infectious diseases” Or: • the study of disease in populations, how diseases increase over space, in severity, or over time.

14. A central concept to epidemiology is that different pathogen populations have different disease cycles. I. Monocyclic = single cycle (simple interest) • Pathogens that complete one or even part of one disease cycle/year are called monocyclic • In monocyclic pathogens the primary inoculum is the only inoculum available for the entire season. There is no secondary inoculum and no secondary infection. • The amount of inoculum produced at the end of the season, however, is greater than at the start of the season so the amount of inoculum may increase steadily from year to year.

15. This representation of plant disease over time is referred to as a “Disease Progress Curve” • Graphically, disease caused by monocyclic pathogens looks like a saturation curve.

17. Examples of Monocyclic Diseases • Blackleg of potato (Erwinia caratovora) • Verticilliumwilt • Cereal Cyst Nematode

18. II. Polycyclic = multiple cycles/year (compound interest) • Most pathogens go through more than one (2-30) disease cycle in a growing season and are referred to as polycyclic. • Only a small number of sexual spores or other hardy structures survive as primary inoculum that cause initial infections. • Once infection takes place, large numbers of asexual spores are produced as secondary inoculum at each infection site. • These spores can produce new (secondary) infections that produce more asexual spores and so on. • With each cycle the amount of inoculum is multiplied many fold.

20. Many of these pathogens are disseminated primarily by air Or air-borne vectors and are responsible for most of the explosive epidemicsin most crops Examples of Polcyclic Diseases • Downy mildews • Powdery mildews • Late blight of potato • Leaf spots • Blights • Grain rusts • Aphid borne viruses • Root-knot nematodes

21. III. Polyetic (multi-year) cycles • Some pathogens take several years before inoculum they produce can be disseminated and initiate new infections. • May not cause many new infections over a given area in a year, amount of inoculum does not increase greatly within a year. • However, because they survive in perennial hosts they have almost as much inoculum as they had at the end of the previous year. • Inoculum may increase steadily(exponentially) from year to year and can cause severe outbreaks when considered over several years.

22. Examples of Polyetic Diseases: • Some diseases of trees • Dutch elm disease • Pear decline • Citrus tristeza • Fungal vascular wilts • Mycoplasmal yellows • Viral infections

23. Implications for Disease Management Strategies Monocyclic Diseases • Reduce the amount of primary inoculum, or affect the efficiency of invasion by the primary inoculum. Polycyclic Diseases • Reducing the amount of primary inoculum has less impact. • Reducing the rate of increase of the pathogen more beneficial

24. Principles of epidemiology indicates that control measures can do this in only two ways. 1. They may reduce (or delay) disease at the beginning of the season (Xo) or 2. They may decrease the rateof disease development (r) during the growing period.