Download - Kuliah Fitopat Disease Progress
-
8/12/2019 Kuliah Fitopat Disease Progress
1/111
-
8/12/2019 Kuliah Fitopat Disease Progress
2/111
Disease Progress
Disease on plants usually starts
out at a low level, a small number
of plants affected and a smallamount of plant tissue affected,
and it becomes of concern to us
only when its incidence andseverity increases with time.
-
8/12/2019 Kuliah Fitopat Disease Progress
3/111
Disease Progress
When we look at some examples ofplant disease epidemics from thepublished literature, we not only
notice that the incidence or severitystarts near zero and then increasesdramatically, but we alsocan discernsome distinct patterns of
development with time.
-
8/12/2019 Kuliah Fitopat Disease Progress
4/111
Disease Progress
For example, in Phytophthora blight of
pepper seedlings (Phytophthora
capsici) and Fusarium kernel rot(Fusarium moniliforme) of maize,
disease progress is roughly linear
(allowing for some minor deviationsthat we can consider random error)
-
8/12/2019 Kuliah Fitopat Disease Progress
5/111
Phytophthora blight of pepper seedlings
-
8/12/2019 Kuliah Fitopat Disease Progress
6/111
Fusarium kernel rot of maize
-
8/12/2019 Kuliah Fitopat Disease Progress
7/111
Disease Progress
On the other hand, in bean rust (Uromyces
phaseoli) and grey leaf spot of corn
(Cercospora zeae-maydis), there is a
definite upward curve; that is, diseaseincreases at an increasing rate, a curve we
could call exponential.
-
8/12/2019 Kuliah Fitopat Disease Progress
8/111
Bean rust
-
8/12/2019 Kuliah Fitopat Disease Progress
9/111
Grey leafspot of
maize
-
8/12/2019 Kuliah Fitopat Disease Progress
10/111
Disease Progress
Obviously plant disease cannot continue toincrease forever, and as the level of diseaseapproaches 100%, the disease progress
curve gradually flattens out. For example, inepidemicssuch as the infection of beans bySclerotium rolfsiior the infection of tobaccoby Phytophthora parasiticavar. nicotianae,
disease progress starts out looking linearbut slows down as it approaches amaximum.
-
8/12/2019 Kuliah Fitopat Disease Progress
11/111
Sclerot ium rol fs i ion beans
-
8/12/2019 Kuliah Fitopat Disease Progress
12/111
Black shank on tobacco
-
8/12/2019 Kuliah Fitopat Disease Progress
13/111
Disease Progress
Likewise, the disease progress curves of
Puccinia graminissubsp. graminicolaon
ryegrass and Pyrenophora teresf. sp. teres
on barley appear exponential at first, but astime goes on and the incidence and severity
of disease approach 100%, the rate of
disease progress gradually slows to zero,giving both curves a somewhat sigmoid
shape ("S" shape).
-
8/12/2019 Kuliah Fitopat Disease Progress
14/111
Black stem rust on ryegrass
-
8/12/2019 Kuliah Fitopat Disease Progress
15/111
Net blotch on barley
-
8/12/2019 Kuliah Fitopat Disease Progress
16/111
To be sure, not all examples of
disease progress can be as neatly
categorized as these, but in general
plant disease epidemics tend to be
either roughly linear or exponential in
the early stages, and they tend to
level off as they approach some limit.
-
8/12/2019 Kuliah Fitopat Disease Progress
17/111
The impact of plant disease and the
losses that it causes are a function of
disease progress. To reduce this
impact, we need not eliminate the
disease, we merely need to keep
disease development below anacceptable level.That means that the
progress of disease and the factors that
influence disease progress must beunderstood in quantitative terms.
-
8/12/2019 Kuliah Fitopat Disease Progress
18/111
1.what kinds of diseases lead to linear disease
progressand what factors affect the slope of the line
(the rate of disease progress).
2. what kinds of diseases tend to produce
exponential disease progresscurves and how we
can reduce both the starting level of disease andthe
rate of epidemic development.
3. why epidemics sometimes level off and what
imposes limits to their development.
We have to know :
-
8/12/2019 Kuliah Fitopat Disease Progress
19/111
The Cyclical Nature of Plant
Disease
-
8/12/2019 Kuliah Fitopat Disease Progress
20/111
The inoculum,
which might
consist of
gains entry into and establishment
within the host tissues through the
process of infection.
http://images.google.co.id/imgres?imgurl=http://www.apsnet.org/Education/IllustratedGlossary/PhotosS-V/stoma.jpg&imgrefurl=http://www.apsnet.org/Education/IllustratedGlossary/PhotosS-V/stoma.htm&h=275&w=400&sz=31&hl=id&start=16&tbnid=gxzjSmri90v-_M:&tbnh=85&tbnw=124&prev=/images%3Fq%3Dstomatal%2Bopening%26svnum%3D10%26hl%3Did%26lr%3D -
8/12/2019 Kuliah Fitopat Disease Progress
21/111
The pathogen develops within the
host and eventually begins to
produce new inoculum, which, in
turn, can be dispersed to new
susceptible sites to initiate new
infections.
-
8/12/2019 Kuliah Fitopat Disease Progress
22/111
Pathogens that produce only one
cycle of development (one infection
cycle) per crop cycle are called
monocyclic, while pathogens thatproduce more than one infection
cycle per crop cycle are called
polycyclic.
-
8/12/2019 Kuliah Fitopat Disease Progress
23/111
Generally in temperate climatesthere isonly one crop cycle per year, so the terms
"monocyclic" and "polycyclic" are basedon the number of cycles per year. Intropical or subtropical climates, however,there can be more than one crop cycle
per year, and it is important to rememberthat "monocyclic" and "polycyclic" arebased on a single crop cycle. These sameterms are used to describe the epidemics
as well as the pathogens, so we oftenspeak of a "monocyclic epidemic"or a"polycyclic epidemic".
-
8/12/2019 Kuliah Fitopat Disease Progress
24/111
-
8/12/2019 Kuliah Fitopat Disease Progress
25/111
Change : often increase -- a dynamic process
Disease : dealing with diseases, not just the
pathogen (or plant/crop)
Host : Organism infected (or potentially
infected) by another organism
Population : a population phenomenon
Time and space : two physical dimensions
of interest.
-
8/12/2019 Kuliah Fitopat Disease Progress
26/111
Epidemiology:
Study of epidemics.
Science of disease in populations. Ecology of disease.
Study of the spread of diseases, in space andtime,
with the objective to trace factors that areresponsible for, or contribute to, epidemic
occurrence.
The science of populations of pathogens inpopulations of host plants, and the diseases
resulting therefrom under the influence of
the environment and human interferences.
-
8/12/2019 Kuliah Fitopat Disease Progress
27/111
-
8/12/2019 Kuliah Fitopat Disease Progress
28/111
All plant diseases result from a three-way
interaction between the host, the pathogen
andthe environment.
An epidemic develops if all three of these
factors are favourable to diseasedevelopment.
Therefore, disease can be controlled by
manipulating one or more of these factorsso
that conditions are unsuitable for replication,
survival or infection by the pathogen.
-
8/12/2019 Kuliah Fitopat Disease Progress
29/111
Since the beginning of agriculture, generations
of farmers have been evolving practices for
combating the various plagues suffered by our
crops. Following our discovery of the causes ofplant diseases in the early nineteenth century,
our growing understanding of the interactions of
pathogen and host has enabled us to develop a
wide array of measures for the control of specific
plant diseases.
-
8/12/2019 Kuliah Fitopat Disease Progress
30/111
From this accumulated knowledge
base, we can distill some general
principles of plant disease controlthat can help us address the
management of new problems onwhatever crop in any environment.
O h t f i i l fi t
-
8/12/2019 Kuliah Fitopat Disease Progress
31/111
One such set of principles, first
articulated by H. H. Whetzel in 1929
and modified somewhat by variousauthors over the years, has been
widely adopted and taught to
generations of plant pathologystudents around the world. These
"traditional principles", as they have
come to be known, were outlined by acommittee of the US National
Academy of Sciences, 1968.
-
8/12/2019 Kuliah Fitopat Disease Progress
32/111
Avoidanceprevent disease by selecting a time of the year or
a site where there is no inoculum or where the environment isnot favorable for infection.
Exclusionprevent the introduction of inoculum.
Eradicationeliminate, destroy, or inactivate the inoculum.
Protectionprevent infection by means of a toxicant or some
other barrier to infection.
Resistanceutilize cultivars that are resistant to or tolerant of
infection.
Therapy
cure plants that are already infected.
Traditional Principles of Plant Disease Control
-
8/12/2019 Kuliah Fitopat Disease Progress
33/111
While these principles are as valid today asthey were in 1929, in the context of modern
concepts of plant disease management, theyhave some critical shortcomings.
First of all,these principles are stated inabsolute terms (e.g., "exclude", "prevent", and
"eliminate") that imply a goal of zero disease.Plant disease "control" in this sense is notpractical, and in most cases is not evenpossible. Indeed, we need not eliminate a
disease; we merely need to reduce its progressand keep disease development below anacceptable level. Instead of plant diseasecontrol, we need to think in terms of plant
disease management.
-
8/12/2019 Kuliah Fitopat Disease Progress
34/111
-
8/12/2019 Kuliah Fitopat Disease Progress
35/111
Furthermore, considering that different
diseases differ in their dynamics, they donot indicate the relative effectiveness of
the various tactics for the controlof a
particular disease. They also fail to show
how the different disease control
measures interact in their effects on
disease dynamics. We need some means
of assessing quantitatively the effects ofvarious control measures, singly and in
combination, on the progress of disease.
-
8/12/2019 Kuliah Fitopat Disease Progress
36/111
Finally, the traditional principles of
plant disease control tend to
emphasize tactics without fitting
them into an adequate overall
strategy.
Does this mean that we should
abandon the traditional principles? Of
course not! We merely have to fit theminto an appropriate overall strategy
based on epidemiological principles.
The Epidemiological Basis of Disease
-
8/12/2019 Kuliah Fitopat Disease Progress
37/111
The Epidemiological Basis of Disease
ManagementPlant disease epidemics can be classified into two basic types,
monocyclic and polycyclic, depending on the number ofinfection cycles per crop cycle. (See: The Cyclical Nature of
Plant Disease.)
-
8/12/2019 Kuliah Fitopat Disease Progress
38/111
The early stages of a monocyclic epidemic can be
described quite well by a linear model, while the early
stages of a polycyclic epidemic can be described with an
exponential model. Since we are concerned with keeping
disease levels well below 100%, there is no need to
adjust the models for approaching the upper limit, and
we can use the simple linear and exponential models toplan strategies:
Examining these models we can see that in both there are
-
8/12/2019 Kuliah Fitopat Disease Progress
39/111
1. Reduce the initial inoculum (Qin the
monocyclic model and xoin the polycyclic
model). (Actually xois the initial incidence of
disease, which is proportional to the initialinoculum.)
2. Reduce the rate of infection (Rin the
monocyclic model and rin the polycyclicmodel)
3. Reduce the duration of the epidemic (the time,
t, at the end of the epidemic)
Examining these models, we can see that in both there are
three ways in which we can reduce xat any point in the
epidemic:
-
8/12/2019 Kuliah Fitopat Disease Progress
40/111
These can be used as three major
strategiesfor managing plant diseaseepidemics, and we can organize our
plant disease control tacticsunder one
or more of these overall strategies.
Furthermore, by means of the model we
can assess the quantitative impact of
each strategy, not only by itself, but in
its interaction with others.
-
8/12/2019 Kuliah Fitopat Disease Progress
41/111
It is clear from the above model of a monocyclic
epidemic that Q, R, and t have equal weight intheir effect on x. A reduction in the initial
inoculum or the rate of infection will result in a
reduction in the level of disease by the sameproportion at any time, t, throughout the epidemic.
If tcan be reduced (for example, by shortening the
season), disease will be reduced proportionately.
The monocyclic
model
The polycyclic
-
8/12/2019 Kuliah Fitopat Disease Progress
42/111
The polycyclic
model If ris very high, the apparent
effect of reducing xois to delaythe epidemic.
If ris very high, xomust be reduced to very
low levels to have a significant effect on theepidemic.
Reducing rhas a relatively greater effect onthe epidemic than reducing x
o.
Reducing xomakes good strategic sense onlyif ris low or if ris also being reduced.
-
8/12/2019 Kuliah Fitopat Disease Progress
43/111
The Traditional Principles Revisited
To make the conceptual leap from disease
control to disease management, the
traditional principles can be modified by
fitting them as tactics within each of the
three major disease management strategies
and by slightly changing the wording toreflect the quantitative impact of the action
rather than an absolute effect:
-
8/12/2019 Kuliah Fitopat Disease Progress
44/111
PRINSIP PENGELOLAAN PENYAKIT
TUMBUHAN
Pada prinsipnya, untuk mengelola penyakit tumbuhanada strategidan ada taktikyang dapat digunakan.
Taktik dipakai untuk mencapai tujuan berdasar strategiyang dicanangkan.
Secara umum, ada tiga strategi yang dapat dilakukanuntuk pengendalian penyakit tumbuhan yaitu :
(1) strategi untuk mengurangi inokulum awal,
(2) strategi untuk mengurangi laju infeksi, dan
(3) strategi untuk mengurangi lamanya epidemi.
Sedangkan taktik pada prinsipnya ada enam, yaituavoidan, ekslusi, eradikasi, proteksi, resistensi, danterapi.
-
8/12/2019 Kuliah Fitopat Disease Progress
45/111
Tactics for the Reduction of Initial Inoculum
Avoidancereduce the level of disease by selecting aseason or a site where the amount of inoculum is loworwhere the environment is unfavorable for infection
Exclusionreduce the amount of initial inoculum introducedfrom outside sources
Eradicationreduce the production of initial inoculum bydestroying or inactivating the sources of initial inoculum(sanitation, removal of reservoirs of inoculum, removal ofalternate hosts, etc.)
Protectionreduce the level of initial infection by means ofa toxicant or other barrier to infection
Resistanceuse cultivars that are resistant to infection,particularly the initial infection
Therapyuse thermotherapy, chemotherapy and/ormeristem culture to produce certified seed or vegetativeplanting stock
Tactics for the Reduction of the Infection
-
8/12/2019 Kuliah Fitopat Disease Progress
46/111
Tactics for the Reduction of the Infection
Rate
Avoidancereduce the rate of production of inoculum, therate of infection, or the rate of development of the pathogenby selecting a season or a site where the environment isnot favorable
Exclusionreduce the introduction of inoculum fromexternal sources during the course of the epidemic
Eradicationreduce the rate of inoculum production duringthe course of the epidemic by destroying or inactivating thesources of inoculum (roguing)
Protectionreduce the rate of infection by means of atoxicant or some other barrier to infection
Resistanceplant cultivars that can reduce the rate ofinoculum production, the rate of infection, or the rate ofpathogen development
Therapycure the plants that are already infected orreduce their production of inoculum
T ti f th R d ti f th
-
8/12/2019 Kuliah Fitopat Disease Progress
47/111
Tactics for the Reduction of the
Duration of the Epidemic
Avoidanceplant early maturing cultivars
or plant at a time that favors rapid
maturation of the crop
Exclusiondelay the introduction of
inoculum from external sources by means
of plant quarantine
PENGENDALIAN PENYAKIT TUMBUHAN
-
8/12/2019 Kuliah Fitopat Disease Progress
48/111
MENGURANGI LAJU INFEKSI
MENGURANGI LAMANYA EPIDEMI
MENGURANGI INOKULUM AWAL
EKSLUSI
AVOIDAN
STRATEGI
Waktu tanam, lahan, lingkungan yg tak cocok untukpatogen
Mengurangi jumlah inokulum awal yang berasal dariluar lahan
Sanitasi, buang sumber inokulum, musnahkan inangantara, dsb.
Aplikasi fungisida, atau buat penghalang infeksi pdtanaman
Kultivar yang tahan terhadap infeksi inokulum awal
Terapi panas, kimia, benih / bag. tan. vegetativ bebaspenyakit
EKSLUSI
TERAPI
ERADIKASI
RESISTEN
PROTEKSI
TAKTIK
AVOIDAN
Laju dikurangi dg waktu tanam, lahan, lingkungan ygtak cocok
Kurangi masuknya inokulum selama terjadinyaepidemi
Tebang, pangkas, musnahkan inokulum saatterjadinya epidemi
Kurangi laju infeksi dengan fungisida ataupenghalang lain
Kultivar yang mengurangi laju in-feksi/perkemb.patogen/inokulum
Sembuhkan tanaman yang telah terinfeksi
EKSLUSI
TERAPI
ERADIKASI
RESISTEN
PROTEKSI
AVOIDAN
Tanaman cepat dewasa agar terhindar dari infeksi
Hambat introduksi inokulum dari luar dengankarantina
-
8/12/2019 Kuliah Fitopat Disease Progress
49/111
-
8/12/2019 Kuliah Fitopat Disease Progress
50/111
Cara pendekatan pendekatan terhadap tanaman
pendekatan yang ditujukan terhadappenyebab penyakit tertentu
Terintegrasi ke dalamMETODA PENGENDALIAN
-
8/12/2019 Kuliah Fitopat Disease Progress
51/111
Penghindaran patogen
Pemilihan daerah pertanian.
Pemilihan waktu tanam.
Penggunaan benih yang bebas penyakit.
-
8/12/2019 Kuliah Fitopat Disease Progress
52/111
Eksklusi patogen
Perawatan bahan tanaman.
Karantina tumbuhan.
Pembasmian serangga vektor.
-
8/12/2019 Kuliah Fitopat Disease Progress
53/111
Erad ikasi patogen
Pergiliran tanam.
Membuang atau menghancurkan tanaman
atau bagian tanaman yang terserang.
Perlakuan tanah.
-
8/12/2019 Kuliah Fitopat Disease Progress
54/111
Perl indungan tanaman
Pengendalian serangga pembawa
patogen.
Mengubah keadaan lingkungan.
Mengubah keadaan zat hara.
M b k t
-
8/12/2019 Kuliah Fitopat Disease Progress
55/111
Mengembangkan tanaman yang
resisten
Resistensi fisiologis
Resistensi mekanis
Resistensi fungsional
Resistensi oleh Khemoterapi
a. Resistensi fisiologis yang biasanya
-
8/12/2019 Kuliah Fitopat Disease Progress
56/111
g y g y
didasarkan kepada adanya zat di dalam
protoplasma yang menghambat infeksi
patogen dan perkembangannya lebihlanjut di dalam tanaman.
b. Resistensi mekanis yang berhubungan
dengan struktur atau morfologi dari bagian-bagian tanaman tertentu meliputi sifat
karakteristik yang dipunyai oleh tanaman
yang menyulitkan patogen mengadakan
kontak secara langsung dengan bagian
yang akan diinfeksinya seperti adanya
lapisan kutikula atau lapisan gabus yang
tebal.
R i i f i l
-
8/12/2019 Kuliah Fitopat Disease Progress
57/111
c. Resistensi fungsionalyang
berhubungan dengan waktu penutupan
stomata.d. Resistensi oleh Khemoterapidimana
terdapat kemungkinan mengubah
ketahanan terhadap patogen yangterdapat dalam protoplasma dengan
pemberian senyawa kimiapada
tanaman. Pada umumnya cara tersebutmemperlambat atau mengurangi
timbulnya penyakit.
T i d ib ik k d
-
8/12/2019 Kuliah Fitopat Disease Progress
58/111
Terapi yang d iberikan kepada
tanaman saki t
Khemoterapi.
Perlakuan panas. Menghilangkan bagian tanaman yang
kena infeksi.
-
8/12/2019 Kuliah Fitopat Disease Progress
59/111
Metoda pengendalian
1. Regulatory
2. Cultural
3. Biological
4. Physical
5. Chemical
-
8/12/2019 Kuliah Fitopat Disease Progress
60/111
Regulatory control
Menangkal suatu patogen dari
suatu inang atau dari suatu areageografis tertentu
-
8/12/2019 Kuliah Fitopat Disease Progress
61/111
Regulatory Control
-
8/12/2019 Kuliah Fitopat Disease Progress
62/111
Cultural control
Mengusahakan tanaman terhindar dari
kontak dengan patogen, mengusahakan
kondisi lingkungan tidak menguntungkanbagi patogen dan melenyapkan atau
mengurangi jumlah patogen pada suatu
tanaman, lahan atau wilayah
-
8/12/2019 Kuliah Fitopat Disease Progress
63/111
Biological control
Meningkatkan resistensi inang atau
menciptakan kondisi yang menguntungkan
bagi mikroorganisma antagonistik bagi
patogen
-
8/12/2019 Kuliah Fitopat Disease Progress
64/111
Physical and chemical control
Melindungi tanaman dari inokulum patogen
yang sudah ada atau akan ada, atau
mengobati suatu infeksi yang sudah/sedang
berlangsung
-
8/12/2019 Kuliah Fitopat Disease Progress
65/111
MENGURANGI LAJU
INFEKSI
MENGURANGI LAMANYA
EPIDEMI
MENGURANGI
INOKULUM AWAL
PENGENDALIAN PENYAKIT TUMBUHAN
EKSLUSI
AVOIDAN
STRATEGI
EKSLUSI
TERAPI
ERADIKASI
RESISTEN
PROTEKSI
TAKTIK
AVOIDAN
EKSLUSI
TERAPI
ERADIKASI
RESISTEN
PROTEKSI
AVOIDAN
-
8/12/2019 Kuliah Fitopat Disease Progress
66/111
PENGENDALIAN PENYAKIT
TUMBUHAN SECARA KIMIAWI
pestisida
PERATURAN PEMERINTAH NO
-
8/12/2019 Kuliah Fitopat Disease Progress
67/111
PERATURAN PEMERINTAH NO.
7 TAHUN 1973
Untuk melindungi keselamatan manusia
dan sumber-sumber kekayaan alam
khususnya kekayaan alam hayati, dansupaya pestisida dapat digunakan efektif,
maka peredaran, penyimpanan dan
penggunaan pestisida diatur dengan
Peraturan Pemerintah No. 7 Tahun 1973.
Dalam peraturan tersebut antara lain
ditentukan bahwa:
tiap pestisida harus didaftarkan kepada Menteri
-
8/12/2019 Kuliah Fitopat Disease Progress
68/111
p p pPertanian melalui Komisi Pestisida untuk dimintakanizin penggunaannya
hanya pestisida yang penggunaannya terdaftar dan
atau diizinkan oleh Menteri Pertanian boleh disimpan,diedarkan dan digunakan
pestisida yang penggunaannya terdaftar dan ataudiizinkan oleh Menteri Pertanian hanya boleh
disimpan, diedarkan dan digunakan menurutketentuan-ketentuan yang ditetapkan dalam izinpestisida itu
tiap pestisida harus diberi label dalam bahasaIndonesia yang berisi keterangan-keterangan yang
dimaksud dalam surat Keputusan Menteri PertanianNo. 429/ Kpts/Mm/1/1973 dan sesuai denganketentuan-ketentuan yang ditetapkan dalampendaftaran dan izin masing-masing pestisida.
Wh t i f i id ?
-
8/12/2019 Kuliah Fitopat Disease Progress
69/111
What is a fungicide?
Fungicides are pesticides that specifically killfungi or inhibit fungal development
About 40 different classes of fungicides used for
plant protection
Classes are based on target site andbiochemical mode of action
-
8/12/2019 Kuliah Fitopat Disease Progress
70/111
M 14 3 11 1 12 19 2 7 4 33multisite aromatic
hydrocarbons
sterol
biosynthesis
inhibitors
QoIs benzimidazoles phenylpyrroles polyoxins dicarboximides carboximides phenylamides phosphonates
protein-proteinbonds
lipidperoxidation
sterol integrationin cell
membranes
mitochondrialrespiration in
complex III
(cyt b)
beta-tubulinassembly in cell
division
os-1histidinekinase in
osmotic
regulationpathways
chitin(cell wall)
synthesis
os-2histidinekinase in
osmotic
regulationpathways
mitochondrialrespiration in
complex II
(succinatedehydrogenase)
RNA polymerase unknown
Mzmancozeb
PcPCNB
Fefenarimol
Azazoxystrobin
Tmthiophanate-
methyl
Flfludioxonil
Pdpolyoxin-D
Ipiprodione
Ftflutolanil
Mfmefenoxam
Fafosetyl-Al
Chchlorothalonil
Mymyclobutanil
Flfluoxastrobin
Vivinclozlin
Boboscalid
Cucopper
hydroxide
Prpropiconazole
Pypyraclostrobin
Tdtriadimefon
Tftrifloxystrobin
Trtriticonazole
CCllaassssiiffiiccaattiioonnTTaabblleeooffTTuurrffggrraassssFFuunnggiicciiddeess
bbaasseeddoonnmmooddeeooffaaccttiioonnmmoorreeiinnffooaattwwwwww..ffrraacc..iinnffoo
aanndd
wwwwww..ttuurrffppaatthhoollooggyy..uuccrr..eedduu
Multi-site Site-specific
Systemicity
-
8/12/2019 Kuliah Fitopat Disease Progress
71/111
Systemicity
Do not penetrate into plant
Redistribute on plant
surfaces Multi-site inhibitors
Kills spores/inhibitsgermination
Protectant only
Broad spectrum
Penetrate into plant
Redistribute on & within
plants Single-site inhibitors
Inhibits spore germinationand or mycelial growth
Protectant and curative
Selective
Non-systemic Systemic
Non systemics
-
8/12/2019 Kuliah Fitopat Disease Progress
72/111
Non-systemics
Mimimal redistribution fromthe point of deposition
Works by contact with the
fungus
Adequate coverage isessential
On the cuticle
Redistributed washed off by
water EBDCs, Chlorothalanil, etc.
-
8/12/2019 Kuliah Fitopat Disease Progress
73/111
Systemics
Local Systemic
Local redistribution
from the point of
deposition On the cuticle
Through the leaf
(translaminar)
Extent is variable
-
8/12/2019 Kuliah Fitopat Disease Progress
74/111
Systemics
Limited systemic
(acropetal penetrant)
Good movement from
the point of application Through tissues
Inside the vasculature
Bulk movement
DMIs, Phenylamides
-
8/12/2019 Kuliah Fitopat Disease Progress
75/111
Systemics
True Systemics(Basipetal penetrant)
Only one fungcide
Fosetyl-Al Moves through plant
Down into roots
Good against soil-
borne oomycetes
Single Site v Multi-site
-
8/12/2019 Kuliah Fitopat Disease Progress
76/111
Single Site v. Multi site
Systemic v. non-Systemic
Protectant only
Can wash off
Shorter application
intervals
Broad spectrum
Low Risk of Resistance
Protectant and curative
Less prone to washing off
Longer application
intervals
Selective
High Risk of Resistance
Non-systemic/Multi-Site Systemic/Single Site
Pola Laku Kimiawi pada
-
8/12/2019 Kuliah Fitopat Disease Progress
77/111
Biological mode of action
Aksi Fungisida dapat diekspresikan melalui
salah satu dari dua cara ekspresi fisik
Penghambatan perkecambahan
spora.
Penghambatan pertmbuhan jamur.
Pola Laku Kimiawi pada
Pengendalian Penyakit Tanaman
-
8/12/2019 Kuliah Fitopat Disease Progress
78/111
Physiological mode of action
Apa yang terjadi pada tingkatan
seluler shg dapat menyebabkanpengaruh visibel pada
perkecambahan spora dan
pertumbuhan jamur?
-
8/12/2019 Kuliah Fitopat Disease Progress
79/111
Mengapa perlu mengenali pola laku
fungisida secara fisiologis?
For resistance management and preservation of fungicide
effectiveness.
Untreated
Treated
-
8/12/2019 Kuliah Fitopat Disease Progress
80/111
The physiological mode of
action Fungicides are metabolic inhibitors andtheir modes of action can be classified into
four broad groups.
Inhibitors of electron transport chain. Inhibitors of enzymes.
Inhibitors of nucleic acid metabolism and
protein synthesis.
Inhibitors of sterol synthesis.
A typical cell and cell components
-
8/12/2019 Kuliah Fitopat Disease Progress
81/111
A typical cell and cell components
Electron transport chain
Enzymes
Nucleic acid metabolism
and protein synthesis
Sterol synthesis
-
8/12/2019 Kuliah Fitopat Disease Progress
82/111
Inhibition of electron transport chain
(Respiration in mitochondria) Sulfur
Disrupts electron transport along the
cytochromes
Strobilurins (azoxystrobin, kresoxim-methyl,pyraclostrobin, trifloxystrobin)
Inhibit mitochondrial respiration, blocking the
cytochrome bc1 complex.
-
8/12/2019 Kuliah Fitopat Disease Progress
83/111
Synthesis from Natural Products
-
8/12/2019 Kuliah Fitopat Disease Progress
84/111
Oudemansin A
O
OO
O
Strobilurin A
OO
O
Enol ether stilbene
OO
O
Enol Ether Group
CN
O O
N N
OO
O
Oxime Ether Group
O
OON
O
Synthesis from Natural Products
Inhibition of enzymes
-
8/12/2019 Kuliah Fitopat Disease Progress
85/111
Inhibition of enzymes
Copper
Nonspecific denaturation of proteins andenzymes.
Dithiocarbamates(maneb, manzate, dithane, etc)
Inactivate SH groups in amino acids, proteins
and enzymes.
Substituted aromatics(chlorothalonil, PCNB)
Inactivate amino acids, proteins and enzymes
by combining with amino and thiol groups.
Organophosphonate(fosetyl-Al)
Disrupts amino acid metabolism.
-
8/12/2019 Kuliah Fitopat Disease Progress
86/111
Inhibition of nucleic acid metabolism
and protein synthesis
Benzimidazoles(thiophanate-methyl)
Inhibit DNA synthesis (nuclear division).
Phenylamides(mefenoxam) Inhibits RNA synthesis.
Dicarboximides(iprodione, vinclozolin)
Inhibits DNA and RNA synthesis, cell divisionand cellular metabolism.
-
8/12/2019 Kuliah Fitopat Disease Progress
87/111
Inhibition of sterol synthesis
(Inhibit demethylation of ergosterol)
Ergosterol is the major sterol in most fungi.
It is essential for membrane structure and function.
-
8/12/2019 Kuliah Fitopat Disease Progress
88/111
Sterol inhibiting fungicides
Imidazoles(imazalil)
Triazoles(propiconazole, myclobutanil,
tebuconazole, triflumazole) Morpholines(dimethomorph)
Inhibits sterol production at different site than
imidazoles and triazoles. Affects cell wall
production.
-
8/12/2019 Kuliah Fitopat Disease Progress
89/111
Biological control of plant
pathogensChristine Roath
O i
-
8/12/2019 Kuliah Fitopat Disease Progress
90/111
Overview
What is biological control, what are thebenefits to its use
Mechanism of biological control
Requirements of successful biocontrol
Working example of biocontrol
What is biological control?
-
8/12/2019 Kuliah Fitopat Disease Progress
91/111
What is biological control?
First coined by Harry Smith in relation tothe biological control of insects
Suppression of insect populations by native or
introduced enemies Generic terms
A population-leveling process in which the
population of one species lowers the numberof another
-
8/12/2019 Kuliah Fitopat Disease Progress
92/111
Why use biological control?
-
8/12/2019 Kuliah Fitopat Disease Progress
93/111
Why use biological control?
WILL: Chemical pesticides
Implicated in ecological, environmental, and human healthproblems
Require yearly treatments
Broad spectrum Toxic to both beneficial and pathogenic species
BUT:
Biological control agents Non-toxic to human
Not a water contaminant concern Once colonized may last for years
Host specific Only effect one or few species
-
8/12/2019 Kuliah Fitopat Disease Progress
94/111
-
8/12/2019 Kuliah Fitopat Disease Progress
95/111
Mechanisms of biological control of
-
8/12/2019 Kuliah Fitopat Disease Progress
96/111
g
plant pathogens
Destructive mycoparasitismtheparasitism of one fungus by another
Direct contact
Cell wall degrading enzymes Some produce antibiotics
Example
Trichoderma harzianum, BioTrek, used as seedtreatment against pathogenic fungus
Requirements of successful
-
8/12/2019 Kuliah Fitopat Disease Progress
97/111
q
biocontrol
1. Highly effective biocontrol strain must beobtained or produced
a. Be able to compete and persist
b. Be able to colonize and proliferatec. Be non-pathogenic to host plant and
environment
Requirements of successful
-
8/12/2019 Kuliah Fitopat Disease Progress
98/111
q
biocontrol
2. Inexpensive production and formulationof agent must be developed
a. Production must result in biomass with
excellent shelf liveb. To be successful as agricultural agent must
be
i. Inexpensive
ii. Able to produce in large quantities
iii. Maintain viability
Requirements of successful
-
8/12/2019 Kuliah Fitopat Disease Progress
99/111
biocontrol
3. Delivery and application must permit fullexpression of the agent
a. Must ensure agents will grow and achieve
their purpose
Coiling of Trichodermaaround a pathogen.(Plant Biocontrol by Trichoderma spp. IlanChet, Ada Viterbo and Yariv Brotman)
-
8/12/2019 Kuliah Fitopat Disease Progress
100/111
Plant pathogen control by
-
8/12/2019 Kuliah Fitopat Disease Progress
101/111
Trichoderma spp.
How is it applied?
Favored by presence of high levels of plant roots
Some are highly rhizosphere competent
Capable of colonizing the expanding root surface
Can be used as soil or seed treatment
http://www.nysaes.cornell.edu/ent/biocontrol/pathogens/images/trichoderma3.jpg
Plant pathogen control by
-
8/12/2019 Kuliah Fitopat Disease Progress
102/111
Trichoderma spp.
Action against pathogenic fungi
1. Attachment to the host
hyphae by coiling
a. Lectin-carbohydrate
interaction
(Hubbard et al., 1983. Phytopathology 73:655-659).
Plant pathogen control by
-
8/12/2019 Kuliah Fitopat Disease Progress
103/111
Trichoderma spp.
Action against pathogenic fungi
2. Penetrate the host cell walls by
secreting lytic enzymes
a. Chitinases
b. Proteases
c. Glucanases
(Ilan Chet, Hebrew University of Jerusalem).
Plant pathogen control by
-
8/12/2019 Kuliah Fitopat Disease Progress
104/111
Trichoderma spp.
Some strains colonize the root withmycoparasitic properties
Penetrate the root tissue
Induce metabolic changes which induceresistance
Accumulation of antimicrobial compounds
Plant pathogen control by
-
8/12/2019 Kuliah Fitopat Disease Progress
105/111
Trichoderma spp. Commercial availability
T-22 Seed coating, seed pieces, transplant starter
Protects roots from diseases caused by Pythium,Rhizoctoniaand Fusarium
Interacts with the Rhizosphere, near the root hairs
and increases the available form of nutrients
needed by plants.
-
8/12/2019 Kuliah Fitopat Disease Progress
106/111
-
8/12/2019 Kuliah Fitopat Disease Progress
107/111
SUSTAINABLE MANAGEMENT OF
SOIL-BORNE PLANT DISEASES
a reduc t ion of
-
8/12/2019 Kuliah Fitopat Disease Progress
108/111
a reduc t ion of
biod ivers i ty of
so i l organisms
Soi l-borne
diseases
Resto r ing beneficial
organism s that attack,
repel, or o therwise
antagonize disease-causing pathogens w i l l
render a soil disease-
suppressive
Plants grow ing in
disease-sup pressive soi l
resist diseases much
bet ter than in so i ls low inbio log ical divers i ty.
Benef ic ial organisms can be
added d irect ly, or the soi lenv i ronment can be made mo re
favorable for them throug h us e
of compost and other organic
amendments.
Compost qual itydetermines its
effectiv eness at
suppress ing
soi l-borne plant
diseases.
Why Disease?
-
8/12/2019 Kuliah Fitopat Disease Progress
109/111
yPlant diseases result when a susceptible host
and a disease-causing pathogen meet in a
favorable environment
If any one of these threeconditions were not met,
there would be no
disease.
-
8/12/2019 Kuliah Fitopat Disease Progress
110/111
Many intervention practices (fungicides,methyl bromide fumigants, etc.) focus on
taking out the pathogen after its effects
become apparent.
How to emphasizes on making the
environment less disease-favorable and thehost plant less susceptible.
-
8/12/2019 Kuliah Fitopat Disease Progress
111/111