Transcript 5. manajemen penyakit tanaman

MANAJEMEN PENYAKIT
TANAMAN
Prinsip Utama Pengendalian
Penyakit Tanaman dalam Praktek
Tujuan
Pengetahuan/Konsep
Diagnosis
Pengenalan gejala, tanda
Biologi Patogen
Prognosis
Siklus Penyakit
Prinsip-prinsip
Pengendalian
Strategi dan taktik
pengendalian
Aplikasi
Manajemen pertanaman
Prinsip Utama Pengendalian
Sebelum patogen muncul
• Eksklusi = usaha mencegah introduksi atau
menetapnya patogen
Sesudah patogen muncul
• Terapi = prosedur – prosedur yang dilakukan
setelah patogen muncul
Eksklusi Patogen
1. Karantina (Quarantine) = program atau
kebijakan untuk mencegah introduksi
patogen
2. Bahan tanam bebas patogen atau penyakit
a. Certification of seed and other planting
material
b. Treatment of propagation material
“Regulatory Plant Pathology”
(Pengendalian dengan Peraturan / UU)
Penghidaran dari Patogen
Menghidari penyakit tanaman dengan
menanam:
1. Saat inokulum inaktif atau level inokulum
rendah
2. Pada daerah atau area yang tidak endemis
penyakit atau bebas inokulum atau yang
lingkungannya mendukung.
• Memproduksi benih komersial di area yang
jauh dari daerah endemis penyakit
Eradikasi Patogen
• Mengurangi, mengambil, membuang atau
memusnahkan inokulum pada sumbernya baik
pada area atau dari individu tanaman yang telah
terserang
• Rotasi dengan tanaman yang dapat memutus
perkembangan biakan patogen
• Perlakuan dengan bahan kimia, panas dll = soil
sterilization for potting mix, fumigation
• Fungisida eradikan
• Pengendalian Hayati patogen tanaman
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
Ketahanan Tanaman terhadap Patogen
• Mengurangi efektivitas inokulum, dengan
mengurangi keberadaan patogen
Terapi/perlakuan pada tanaman sakit
• Mengobati atau meminimalisasi kehilangan
oleh tanaman sakit dengan bahan kimia atau
mengubah keparahan dengan memanipulasi
lingkungan untuk mengurangi intensitas
penyakit
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
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.
• Knowing how particular pathogens go
through their disease cycle is important in
developing management strategies.
• 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.
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.
• 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.
Examples of Monocyclic Diseases
• Blackleg of potato (Erwinia caratovora)
• Verticilliumwilt
• Cereal Cyst Nematode
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.
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
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.
Examples of Polyetic Diseases:
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Some diseases of trees
Dutch elm disease
Pear decline
Citrus tristeza
Fungal vascular wilts
Mycoplasmal yellows
Viral infections
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
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.