Potato Crop Health
Management through IPM Approach
Outline
i. Introduction:
Crop Diseases, their Losses and control with special reference
to potato pests and diseases.
ii. Traditional
Pest and Disease Control Approaches and their drawback.
iii. Pesticide
use and its impact with special reference to Pakistan.
iv. Integrated
Pest Management (IPM).
v. Brief
History of IPM.
vi. Components
of IPM.
vii.
IPM implementation through TOF-FFS approach
viii.
IPM
Model in Pakistan and its Progress.
ix. Benefits
of IPM.
x. IPM
in Potato through FFS approach in Northern Areas.
1. Introduction.
Potato ranks third among food
crops after wheat and rice and fifth in total production in
Pakistan. It produces high energy and nutritional value per
unit area than wheat, rice and maize. Although potato
production in Pakistan has increased many folds but it’s per
acre yield is far less than in other parts of the world (Malik,
1995). Among the various factors responsible for its low per
acre production, potato diseases are considered to be the most
important. More than 18 potato diseases are reported in the
country, of which 13 are of common occurrence. Their
importance, however, varies considerably in different potato
growing areas (Ahmad et al., 1991). Most commonly
occurring potato diseases in Pakistan are early blight,
powdery and common scab, black scurf, stem rot, soft rot,
brown rot, wilts, potato cyst nematode and root knot nematode
(Ahmad, 1998). Diseases with mycoplasma pathogens and soil
borne disease of potato caused serious problems in major
potato growing areas of Punjab.
The
Potato crop in Pakistanis affected by many pests and diseases,
and of theses potato viruses, powdery scab, potato cyst
nematode, aphids and white grub are the most damaging ones.
Surveys done by Pakistani workers have revealed that viruses,
powdery scab and aphids are wide spread, white grub are
serious problems in the northern hilly areas (Table 1-4).
Table
1: Diseases caused by fungi
Diseases |
Fungi (Pathogen) |
Black Scurf |
Rhizoctonia solani |
Earlry Blight |
Alternaria solani |
Fusarium dry rot |
Fusarium sp |
Fusarium rot |
Fusarium spp |
Late
blight |
Phytophthora infestans |
Powdery scab |
Spongospora subterranean |
Wilt/Verticillium wilt |
V. albo-atrum & V.
dahliae |
Recommended Control Measures for Fungal Diseases
-
Wet poorly drained areas should
be avoided for potato cultivation.
-
Use disease free seed combined
with seed treatment with benomyl.
-
Seed should be planted on raised
beds and in well-drained soil to encourage fast growth of
the seedlings.
-
Harvest the crop as soon as the
tubers are mature, which can reduce the number of sclerotia
on tubers.
-
Apply boric acid before storage.
-
Destroy and burn the plant
debris before sowing.
-
Harvest carefully to avoid
bruises and injuries to potato tubers.
Table 2: Diseases caused by Bacteria
Diseases |
Bacteria (Pathogen) |
Bacterial wilt |
Ralstonia (Pseudomonas) solanacearum |
Black leg and soft rot |
Erwinia carotovora spp. carotovora and carotovora spp.
atroseptica |
Common scab |
Streptomyces scabies |
Recommended Control Measures for Bacterial Diseases
Preventative Measures
-
Use of healthy seed tubers.
-
Cultivation in un-infested
fields.
-
Destruction of diseased plant
debris.
-
Cultural practices to stop
spread.
-
Long rotation.
-
Destruction of host plants etc.
Curative measures
-
Disinfection of seed tubers.
-
Spray.
Table 3: Diseases Caused by Viruses
Diseases |
Potato leaf roll virus |
Potato mop top virus |
Potato virus A |
Potato virus M |
Potato virus S |
Potato virus X |
Potato virus Y |
Phytoplasma |
Recommended Control Measures for Viral Diseases
-
Use virus free, certified seed
potato.
-
Control the aphid vector.
-
Use resistant varieties.
-
Roguing.
-
Heat treatment of tubers.
-
Modification of cropping
procedure.
-
Chemical control of vector
(Insects, nematodes and fungi)
-
Non-chemical control of vectors
(barriers and reflective mulches, oil sprays, biological
control by predators).
-
Plant resistant to
-
Assess the health of tuber
stocks by serological tests through ELISA, after harvest
Table 4: Diseases Caused by Nematodes
Diseases |
Potato cyst nematode |
Root
knot nematode (Meloidogyne spp.) |
Recommended Control Measures for Nematodes
-
Nematodes cyst on root can be
observed at flowering stage.
-
Soil analysis for extraction of
cyst also provides an excellent mean of diagnosis.
-
Use of resistant and tolerant
varieties (Saif et al., 2000).
2. Traditional Pest and
Disease Control Approaches and their Drawback
Traditional
Approach
2.1
Chemical control.
Traditionally,
chemical control was thought to be the easiest method because
farmers could observe the immediate effect of chemicals on
pathogens and crop. However, it should be realized that
chemicals can not eliminate a pathogen but can only suppress
it only upto a certain extent and the remaining pathogens are
again in a position to build-up the required fungal population
to cause losses.
2.2
Cultural control.
Efforts to
reduce reliance on synthetic chemicals have built on a number
of traditional approaches-including cultural controls (such as
altering planting dates or pattern), use of pest-resistant
crop varieties and simple forms of biological control (such as
addition of an organism to suppress the growth of pathogens).
Cultural control, the most widespread of these approaches, try
to “outsmart” pathogens by manipulating the physical
environment. For example, flooding helps to reduce disease
incidence of panama disease of banana caused by Fusarium
oxysporum f. sp. cubense (Mehrotra, 1980). Intercropping is a
popular cultural technique showing much future promise for
reducing diseases damage, particularly in most traditional
farming systems. Sometimes, one crop is used to attract
pathogenic disease away from other more important or more
susceptible crop. In Eritrea, for example, subsistence farmers
got good yield which attracts some and protection against
foliar diseases in sowing of wheat and barley together. It is
due to the fact that a wheat rust pathogen does not infact
barley and barley pathogens do not cause diseases on wheat (Yahyaoui,
2000). Intercropping can also make it harder for pests to
locate their host plants and fosters proliferation of natural
enemies (Risch, 1981). Intercropping may thus have a role to
decrease the need for insecticides.
2.3 Use of
resistant varieties
Developing
resistant varieties is perhaps the most widely used
traditional means of pest control. Use of resistant varieties
is probably cheaper, safest and environmentally sound method
of disease control. It is continuos process to breed resistant
varieties because of adaptability to break the resistant
barrier of plant.
2.4
Drawback of Traditional Approaches in Isolation
Since long
time, man has learned by experience to use many cultural
practices to control the pest losses. These practices are
proper tillage, crop rotation, removal of affected plants and
crop resistance, burning or burying crop residue and
eliminating plants harboring pests. These measures could not
produce desired results in isolation on large scale commercial
cultivation of crops. In addition to this, “grow more”
pressure rendered the traditional methods in sufficient to
control the ever increasing pest problems. Scientific
development in manufacturing of chemicals and their use by
machinery on large scale, opened a new era of chemical control
of pest. When the use of chemicals increased dramatically
after 2nd world war, scientists and the public saw
them as wonder chemicals that would rid the world of insect
pests, weeds and insect transmitted diseases. Over the last
two decades, however, their numerous drawbacks have become
more and more apparent. The major drawbacks of pesticide fall
into three categories.
n
Environment contamination.
n
Human health effects.
n
Pest resistance.
Synthetic
chemicals contaminate the environment in many ways. Widespread
application of chemicals on mono-culture by airplane leads to
drifting and contamination of land and waterways adjacent to
target fields. Chemicals in the soil may eventually also
contaminate ground water, which is considered a severe problem
in many farming areas. Environmental contamination is the
widespread killing of non-target organisms, including
wildlife, cattle, birds, fish, bees and pest’s natural
enemies.
Host
resistance and crop selection has been considered key element
in the evolution of modern agriculture. Use of resistant
cultivars is considered most popular and economical approach
as it may not require as many treatments or as high rates of
chemicals application to achieve adequate pest control.
Although, genetically resistant cultivar is known to be a
reliable means of maintaining healthy plants and reducing crop
losses but traditional local cultivars (Germplasm) have less
yield. On the other hand, developing of resistant variety is a
continuous phenomenon as the organism has the ability to
develop new races to overcome the resistance of the variety.
It is also fact that complete resistant variety can not be
developed against all biotic and biotic factors.
It is
concluded from the above discussion that although, cultural
practices, application of chemicals and use of resistant
varieties provide control against pest but these techniques
could not produce impact on pest control in their individual
application. In the 20th century, agricultural
experts developed strategies of integrated management approach
to adopt the balance and appropriate use of these practices.
This modern approach is called integrated pest management (IPM).
3.
Pesticide use and its impact with special reference to
Pakistan.
3.1 History
and Use of Pesticides in Pakistan.
Pesticides
have played an important in enhancing crop yields through
insect pest control. However, their improper and excessive use
has been the cause of serious health hazards Pesticide use
began in Pakistan in the 1950s for locust control. In 1954,
the government imported formulated pesticides amounting to 254
tones (Habib, 1996). This was the beginning of the pesticide
business in the country. Until 1980, the Plant Protection
Department was responsible for pesticide imports and their
distribution in the country through the national agricultural
extension network. Most of the pesticide imports were used for
aerial spraying to control locust, pests of sugarcane, cotton,
rice, tobacco and fruit crops. The cost of pesticides was
subsidized and aerial spraying was free of charge.
Pesticides
were privatized in 1980 and since then there has been a steady
increase in pesticides import and consumption. As a result,
consumption of pesticides in Pakistan has increased from 665
tones in 1980 to 14,773 tunes in 1990 and 61,229 tones in 2000
worth about 7.7 billion rupees (Ahmad et al, 2002, fig
1). Highest pesticide use is in Punjab, followed by Sindh,
NWFP and Baluchistan (fig 2). Crop wise, largest use is in
cotton followed by rice and vegetables that includes potato
(fig 3). Unfortunately, the widespread use of pesticides has
resulted in complicating pests’ problems. Excessive and
inappropriate pesticide use has disturbed the agro-ecosystem
and killed non-target and environment-friendly organisms,
including environment-friendly organisms, including birds.
Besides this, the excessive inappropriate use has induced pest
resistance and resurgence. Studies show that the populations
of natural enemies in cotton growing areas have declined as
much as 90 percent during the last decade (Husnain, 1999).
3.2
Pesticide Residues in Food and the Environment
Although monitoring of residues in
domestically consumed food products is rather irregular the
few available analyses provide a cause for concern.In
one recent study (Ahad et al, 2001) samples were taken of four
different vegetables: okra (Hibiscus esculentus),
brinjal (Solanum melongena), gourd (Citrullus
vulgaris) and bitter gourd (Momordica charantia)
(table 5). Not surprisingly, pesticide residues were found in
all vegetable samples. In 60% of the samples contamination
exceeded the respective maximum residue limits (MRL).
Table 5:
Pesticide Residues in Food Chain
Type of
Sample |
% of
samples contaminated |
% of
samples >MRL |
Vegetables (Brinjal, okra,
bitter gourd, gourd) |
100 |
60 |
Fruits
(apples) |
100 |
60 |
Cotton
seed oil |
100 |
65 |
Cotton
seed cake |
100 |
65 |
Shallow
ground water |
100 |
30 |
Source: Ahad
et al, 2001
3.3 Health Hazards of Pesticides
Pesticides enter the human body
through three routes: the skin, lungs and the digestive
system. Poisoning can be acute or chronic depending on the
intensity and duration of exposure. The effects of chronic
exposure include various forms of cancer, adverse reproductive
outcomes, impaired immune functions neuropathies,
neurobehavioral disorders and allergic sensitisation
reactions, particularly of the skin (Repetto and Baliga,
1996). Chronic pesticide poisoning can be measured either by
Cholinesterase levels in the blood or pesticide residues in
blood, fatty tissues and mother’s milk. A recent study done on
behalf of Government of Pakistan by UNDP and FAO in cotton
growing areas shows how seriously the pesticide use is
affecting the health of farm workers and laborers (table 6).
About
63% of farm workers get sick every year with workdays lost per
crop season per person range from 2-90 with treatment cost
ranging from Rs. 100-3000 per year.
The
gender implications of health hazards associated with
pesticide use are far from neutral.
Woman farm workers are the largest group affected at the farm
level. It is estimated that 87% of pickers experience sickness
every year. Though labourers working in pesticide industry
also share these hazards but the number is lower than farm
workers.
It is therefore high time that the use of pesticides be
rationalized and alternative approaches promoted.
Table 6: Quantitative Evidence of Pesticide Health Hazards
Exposure during application at farm level
1) |
-
Households affected per season
-
Work days lost per crop season
-
Health treatment costs (Rs/year)
-
Number of deaths |
63%
2-90
100-3000
1/8000
households |
Exposure during cotton harvest
2) |
-
Pickers experienced sickness
-
Average work days lost per crop season
-
Treatment costs (Mill.Rs.)
-
Value of Work lost (Mill.Rs.) |
87%
5
105
660
|
Exposure at local pesticide refilling
facilities 3) |
-
Labourers experiencing sickness
-
Work days lost (per year)
-
Treatment cost (Mill.Rs.)
-
Value of Work lost (Mill.Rs.) |
50%
6
0.46
0.09 |
1) Estimated for 217 million households of 9
major cotton districts in Punjab.
2) Estimated for 5127 thousand tons of cotton
picked by 2.6 million women
3) Estimated for 1000 labourers working at 25
plants in Multan City
Source: UNDP
2001
4.
Integrated Pest Management (IPM).
A wide range of methods is available to manage agriculture
pests that can be grouped into, i. regulatory. ii. Physical.
iii. cultural. Iv. chemical. and v. biological. All of these
have been used individually or in combination. The approach
that addresses the overall health of crop by using all
available methods has become to be known as Integrated Pest
Management (IPM).
Many definitions have been coined to describe integrated pest
management.
According to FAO, IPM could be defined as “pest
management system that, in the context of the associated
environment and the pollution dynamics of the pest species,
utilizes all suitable techniques and methods in as compatible
manner as possible and maintains the pest population at levels
below those causing economic injury (FAO, 1967).
According to more recent definition “Integrated Pest
Management (IPM)
means the careful
consideration of all available pest control techniques and
subsequent integration of appropriate measures that discourage
the development of pest populations and keep pesticides and
other interventions to levels that are economically justified
and reduce or minimize risks to human health and the
environment”. IPM emphasizes the growth of a healthy crop with
the least possible disruption to agro-ecosystems and
encourages natural pest control mechanisms.
5. History of the Concept of IPM
The IPM
concept was developed by a group of entomologists in the late
1950's at the University of California at Riverside led by V.
Stern. The used the term Integrated Control to address the
IPM concept that emphasized the selective use of chemicals so
that natural enemies were conserved in the ecosystem. Later,
the word “control” was replaced with “management” that
includes avoiding the problem and does not aim at eradication
but at maintaining pest populations at acceptable levels. As
it has evolved, IPM is more or less synonym with Integrated
Crop Management that includes all activities aimed at growing
a healthy crop (e.g. soil preparation, irrigation,
fertilization, etc.).
Modern concept
of integrated pest management (IPM) has passed through many
stages. Initially, experts of IPM concentrated on the
development and introduction of spray thresholds but later on
non-chemical control methods were integrated with minimum and
selective use of pesticides. At this stage, packages of IPM
were developed by the scientists at their research
institutions and then disseminated to the farmers through
extension workers. This system could not work well mainly due
to the large variation at farmer field conditions.
Consequently, this system could not maintain the involvement
of farmers. In 1980, new concept was given to IPM that farmers
should be educated on spot about the ecosystem of their own
field. Now more than 50,000 farming communities have started
implementation of IPM programme in a large number of countries
in Asia, Africa and Latin America through the innovative
approach called Farmer Field Schools (Kenmore, 1997).
6. Farmer Led IPM
The Farmer led
IPM approach from earlier one in the sense that it is
participatory. This approach has been developed by the Food
and Agricultural Organization of the United Nations (FAO) and
validated based on
non-formal education methods that could not
assist the farmers to understand the ecosystem of their fields
and to take crop management decisions based on their fields
and to take crop management decisions based on their own
insights but also assisted a group of Asian countries to
establish large scale National IPM programmes based on this
concept. It has a strong bottom up character and became known
as participatory or community IPM. The corner stone of this
approach is:
-
Training of
facilitators (ToF)
-
Season-long
Farmer Fields Schools (FFS)
Use of
Training of Trainers/Facilitators (ToT/F) and Farmer Field
Schools (FFS) has been demonstrated as an effective means of
IPM dissemination. Under the TOT/FFS, 25 participants (mostly
agricultural extension agents, but also representatives from
research, NGOs, or others) are trained over a cropping season.
The schedule is such a participatory one that all participants
of the ToF work in the field with farmers. For first two days
each week, the ToF participants observe a selected field and
do the agro-ecosystem analysis (AESA) and then discuss what
they observed in the field including the soil, the crop
health, need for water, insect pests and their natural
enemies, etc. This is done throughout the season of the crop.
For next two days the ToF participants break into groups of
five each to run 10 FFS and interact with two groups of 25
farmers each in 10 FFS (with 250 farmers). There too, the
farmers do the same AESA, where they collect the insects,
etc., draw their figures and present results, on the basis of
which, further cultural practice and action is decided
collectively. This way, the farmers become more organized,
vigilant and realistic and if something is not clear, some
short & very simple experiments are set up by them to resolve
some unclear issues. Thus, the farmers become better
organized, learn to work in community, make their own day to
day decisions and become experts so that they do not depend on
the chemical companies or extension staff for day to day crop
production advice and become able to resolve conflicts by
themselves.
The world
experience over the years has shown that the best way for the
translation of knowledge is through training of facilitators (TOF)
and Farmer Field School (FFS) activities. One of the main
reasons for the success of this approach is that the decisions
are not preplanned and are not dictated from a central command
but are based on the analysis of agro-ecosystem and site
situation and are made by the farmers with the help of
facilitators.
Through learning framers become experts who are aware of the
principles of the pest management and capable of making
well-informed and independent decision suited to local
conditions. Participatory IPM integrate local farmers’
indigenous knowledge with experience gained in other IPM
programmes and research based IPM recommendations. Thus the
participatory IPM rests itself on four basic principles:
6.1 Principles of Farmer Led IPM
1.
Grow a healthy crop
2.
Understand and conserve defenders
3.
Visit fields regularly
4.
Farmers become experts in crop management
6.1.1 Grow a healthy crop
Growing a healthy crop is a key step in farming. Healthy
plants are stronger and thus better equipped to withstand
attacks by pests and diseases. Many crop management practices
have an effect on the health of the crop and can thus be used
to manage pest problems. For example: good variety, healthy
seeds and seedlings, land preparation, correct spacing,
fertilizer management, water management, crop rotation etc.
6.1.2 Understand and conserve defenders
Biological control agents (parasites, predators, antagonists)
are the defenders of the crop because they are
natural
enemies of the pests. IPM farmers know defenders
and understand their role through regular observations of the
agro-ecosystem. They will try to conserve them by avoiding
pesticides and they will create field conditions that favor
their development.
6.1.3 Visit fields regularly
Regular field visits by the farmer will keep him/her
up-to-date on the condition of the crop. By knowing what is
going on in the field, the farmer can take the correct
decisions and take swift action when needed.
6.1.4 Farmers become experts in crop management
IPM farmers are experts in their own fields. They understand
the agro-ecosystem and are capable of analyzing the field
situation. They continue to improve their crop management by
experimenting in their own field and share their knowledge
with other farmers.
7. Status of
IPM in Pakistan
In Pakistan,
research and development on IPM was initiated in 1971 by
PARC-IIBC station, Rawalpindi (now CABI Bioscience Regional
Centre-Pakistan). A seven-year project on cotton bollworms, a
three-year project on cotton whitefly, and an institutional
three-year support project on IPM, funded by Asian Development
Bank, were the first IPM projects. Similarly, other IPM
activities like introduction of natural enemies of sugarcane
Pyrilla in Sindh and NWFP, cultural control of
Gurdaspur borer in sugarcane, pheromones (methyl eugenol) to
control fruit fly and effective & environment friendly use of
pesticides against cotton pests, were successfully carried out
on large scale by various researchers. Coccinallids sp
was used to control mango hopper and apple scales. Biological
control based IPM technologies for cotton, sugarcane, maize,
fruits and vegetables have also been developed recently. A
project on “Cotton IPM Implementation through Training of
Trainers (TOT) and Farmers Field Schools (FFS) was also
undertaken in Punjab by CABI Bioscience Centre (Poswal &
Williamson1998). At present the centre is running IPM projects
on fruits and vegetables in Balochistan and NWFP provinces.
A number of plant protection
related institutes in the National Agricultural Research
System (NARS) are involved in developing IPM technologies for
major crops. IPM technology comprising of cultural practices,
resistant varieties, use of bio-control agents and selective
use of pesticides has been developed for managing rice pests
in Pakistan. The technology is being disseminated on farmers’
fields and pesticide application has considerably been reduced
in IPM fields.
Many
progressive farmers and Sugar Industries are successfully
rearing and augmenting Trichogramma sp. and
Chrysoperla sp. to control pests of cotton and sugarcane.
Chrysoperla sp. has played an important role in the
control of whitefly during the last two cotton seasons in the
Punjab where chemical control measures had failed. Control of
Helicoverpa sp. has been demonstrated on small scale
with Trichogramma sp. on chickpea, sunflower and
cotton. Pesticides of plant origin like “Triaimol”, “Nimboli”
and “Nimbokil” have been locally developed and are being used
to control important pests.
8. National IPM Programme
Although, work on research and
development, and IPM practice was initiated a long time ago in
Pakistan and has gained momentum in the last decade through
both national and international cooperation projects, IPM was
not institutionalized as in other countries. It needed to be
placed as a coherent programme including all components at the
federal and provincial level. There is awareness and
commitment at the highest level in the Government to
rationalize the use of pesticides and to adopt the alternative
approaches and strategies based on IPM rationale. To achieve
this, it was necessary to translate the Governments strategy
into action plan whereby the IPM moves from project approach
to a viable and sustainable national programme.
IPM was identified as a key element
of sustainable agricultural development in the Policy and
Strategy for Agriculture developed by Government of Pakistan
as part of its response to increasing misuse/overuse of
pesticides and their negative impacts on the society in the
Country. A consultative process among potential stakeholders
was begun, which culminated in the launching of the National
Integrated Pest Management Programme (Nat-IPM) in December
2000.
The National
IPM Programme (Nat-IPM) is led by the National Focal Point for
IPM as the overall Coordinator and assisted by five component
coordinators, one each for policy analysis, education,
information dissemination & public awareness, research &
development and field implementation. The Nat-IPM works under
the guidance of IPM Inter-Ministerial Advisory Committee (IPM-IMC)
and is technically supported by the National Expert Committee
(NIPMEC). It keeps close liaison with NIPMEC members, relevant
federal and provincial research and extension departments,
committees and IPM units. It encourages interaction between
various institutions.
The overall
goals of the Programme are established in the light of the
policy statement given in the policy and strategy document,
“Agricultural Strategies for the First Decade of New
Millennium” issued in June 2000. The agreed IPM programme is
being implemented by partner organizations and coordinated by
Nat-IPM. The Programme operates from National Agricultural
Research Centre Islamabad under the auspices of Pakistan
Agricultural Research Council – an apex body of the Ministry
of Food, Agriculture and Livestock. Various federal and
provincial public sector research and development
organizations, NGOs and international organizations are
participating actively in the Nat-IPM activities. The National
IPM Programme has following vision and objectives:
i.
Vision Statement:
Achieve
environmentally sound and sustainable agricultural production
ensuring food security, social equity, self-reliance and
economic welfare of the producer.
ii.
Goal:
Large scale
and sustainable implementation of IPM in Pakistan,
rationalizing the use of pesticide while maintaining
production levels and increasing farmers’ profit.
iii.
Objectives
The overall
objective is to ensure better coordination and adoption of
effective IPM approaches that are more responsive to the needs
of practitioners and clients
iv.
Specific Objectives
a.
Enhance communication and coordination and
strengthen collaboration among IPM stakeholders.
b.
Promote the adoption of holistic, ecologically
sound and issue oriented IPM approaches.
c.
Facilitate the formulation and execution of
projects, ensuring optimum use of available resources and
maximum impact of IPM efforts on productivity of cropping
systems.
d.
Communicate the results of these efforts, the
benefits of IPM and relevant policy decisions to the public
widely.
e.
Establish International Linkages.
The National
IPM Programme is pursuing its goal and objectives through
establishment of following components:
i.
Policy analysis
ii.
Education
iii.
Information dissemination and public awareness
iv.
Research and development
v.
Field implementation (IPM Practice)
The Programme
is undertaking following strategic steps and actions to ensure
progress of IPM at the National level within the framework of
above components:
i.
Facilitate review of plant protection and IPM policies.
ii.
Introduce/ promote IPM philosophy in educational institutions
by pursuing respective departments for inclusion of IPM
policies and syllabi in schools, colleges and universities.
iii.
Enhance public awareness and establish IPM information network
(IPMIN) to provide updated science based information to the
stakeholders.
iv.
Promote and coordinate research and development in IPM
including study of various agro-ecosystems and indigenous
knowledge.
v.
Facilitate and coordinate IPM implementation by provincial
extension departments and promote cooperation and
collaboration between institutions and provinces.
8.1 Key
Issues and Challenges to the National IPM Programme
The National
IPM Programme in Pakistan faces following challenges:
i.
Make participatory IPM training available to a larger number
of farmers. With in these training programmes special
attention needs to be paid to enabling and encouraging farmer
initiative to continue experimenting after their Farmer Field
Schools (FFS’s) and spread IPM through their communities.
ii.
Develop special programmes to ensure involvement of women in
IPM activities at the grass root level.
iii.
Improve the policy environment for IPM through reform of
policies and practices that directly or indirectly provide
irrational support to chemical pest control.
iv.
Reform crop protection research and extension to be responsive
to support farmer initiatives in IPM.
v.
Enhance coordination and cooperation among government, NGO’s,
donors and international organizations to achieve a high
degree of coherence among different projects and initiative to
optimize the benefits.
vi.
Integrate participatory IPM into policies on sustainable
agriculture and link the FFS approach to other development
fields such as natural resource conservation, and community
development etc.
The Nat-IPM is
developing task forces, led by individual research and
development organizations, to organize a coherent response to
key issues and challenges affecting IPM research and
implementation in the country. Under the umbrella of National
IPM, currently initiatives are being executed with
international support in an integrated strategy to forge a
unified sustainable IPM Programme:
9. Benefits of IPM
IPM emphasizes preventative pest
control methods that provide economical, long term solutions
to pest problems. The three main strategies in IPM program are
chemical, biological and cultural practices. An IPM program
places emphasis on monitoring crops, encouraging natural
biological control and only using chemical control when it is
necessary to prevent imminent crop loss or damage.
IPM is a flexible, dynamic
strategy, which needs updating periodically as information is
received from management practice results.
The use of all three strategies
(chemical, biological, cultural practices) in an integrated
approach has a number of benefits including:
-
Reduction in the use of
chemicals and thus lower production costs.
-
Prevention of excessive residue
levels on produce.
-
Less risk of pests developing
resistance to chemicals.
-
Better survival and
effectiveness of natural enemies.
-
Minimizing the possibility of
pest resurgence
·
Avoiding the development of minor pests into
major pests. Fits well with regular
maintenance and sanitation routines.
9.1
Important Considerations of IPM
Some
considerations with the use of IPM are:
- IPM
requires a greater level of pest life cycle knowledge and
may be more labour intensive and requires commitment from
growers.
- Biological
and cultural controls may not offer an immediate high level
of control as chemical control.
- Pests
previously under control in a managed spray system using
broad insecticide chemicals may become damaging.
- Some
temporary damage may occur in the change from chemical spray
system to integrated system.
9.2
Key Features of IPM
There are a
number of essential ingredients to achieve an effective IPM
program.
·
Accurate monitoring
of pests.
·
This requires
correct insect identification and sampling techniques
·
Use of action level.
·
Requires application
of a control treatment when economic damage is imminent and
must take into consideration abundance of natural enemies
·
Choice of
appropriate control measures
·
Correctly timed and
applied control measures
10. Potato IPM
Integrated Pest Management (IPM) is a systematic approach to
pest management that considers all factors affecting crop
health, including plant nutrition, horticultural practices,
and all suitable means of pest suppression. IPM programs are
based on information obtained by sampling and monitoring, and
this information is used to make management decisions. Pest
management tactics may include biological, chemical,
mechanical, and cultural methods.
IPM
Guidelines can be used in a number of ways:
·
As a checklist for
farmers to evaluate their on-farm pest management programs and
identify areas where management can be improved
·
To verify and
document that IPM is practiced on the farm
·
As an educational
tool which describes the scope and complexity of IPM to
farmers, government officials, community groups and the
general public.
Soil Nutrient Management and
Cultural Practices
Cultural practices are of value in
management of nutrients, weeds, diseases, or insects. The goal
is to supply adequate nutrients with optimum timing for
maximum economical crop yield, while avoiding excesses that
can degrade water quality or adversely affect crop or soil
quality.
Crop rotation is practiced as
follows:
·
Potato field
rotation for two years.
·
Potato field
rotation for one year.
·
Evaluation of filed
for appropriate soil test, nutrient status and pH.
·
Testing of organic
matter status of field.
·
Application of
fertilizer according to soil test results of filed.
·
Use of nitrogen
fertilizer by split application. Some apply through the
planter at planting, and some at cultivation or as a side
dress.
·
If the cover crop in
field was legume or legume/grass mix, its nitrogen
contribution can be calculated and also possible to adjust the
fertilizer for present year crop appropriately.
Pesticides
Application and Records
Only approved
and registered pesticides should be used. Records of pesticide
applications including date, field identification, targeted
pest, pesticide name, formulation, rate and number of acres
treated should be maintained. Pesticide drift is minimized.
Re-entry and pre-harvest intervals are adhered to.
·
Calibration of
pesticide equipment should be calibrated at the start of the
season.
·
It is must to check
the calibration at least once during the season and equipment
can be recalibrated as needed.
·
Records of pesticide
applications should be maintained and organized.
·
Records of planting
dates and stage of crop of treated fields should be
maintained.
·
It is possible to
use the water-sensitive spray cards for the test and coverage
of leaf surfaces of potato crop.
Disease Management
·
Certified virus-free
seed should be planted.
·
Sanitation is
practiced by properly disposing of cull piles (burial or
composting) and by removing volunteer potato plants.
·
Fungicide
application intervals for early blight and late blight are
based on potential for disease severity due to weather
conditions and crop physiological age, e.g. by using BLITECAST
forecasting system. Fields are monitored for diseases
including late blight.
Insect Management
It is possible to monitor the
potato beetle densities weekly by scouting 25 to 50 plants per
field.
Insecticide resistance managements
are practiced as fallow:-
-
Don’t apply the same synthetic
insecticide more than once per season.
-
Don’t apply the same synthetic
insecticide to the same generation of
the potato beetle.
-
Potato beetle egg masses can be
flagged at the beginning of each potato beetle generation to
determine egg hatch and proper timing of microbial
insecticides.
-
Foliar application (Provado) is
limited to one generation potato beetle
(overwintered or summer adults) per season. Foliar
application is not
made where systemic application is make.
-
Soil application is made as a
perimeter treatment to outer six rows or
20" in non-rotated fields or adjacent to fields previously
planted to potato.
-
If soil perimeter application is
used, foliar application is not made in
the same year.
-
Apply microbial insecticides at
least once per generation for control of potato beetle.
-
Non-chemical potato beetle
control methods can be employed, such as
propane flaming, delayed planting, or disruption of movement
from
over wintering sites.
-
Monitor the aphid densities
weekly by examining 50 leaves per week. Aphid
species can be identified and insecticides application will
be best control of the
species present.
-
Potato leafhopper densities are
monitored by examining 50 leaves per week.
Weed Management
Weed management includes one or
more of the following points:
-
Herbicide use is supplemented by
at least one cultivation or hand weeding.
-
Herbicide rates are reduced
through banding of herbicides & cultivation.
-
No herbicides are applied and
weeds are controlled through cultivation. Herbicide rates
are reduced by delaying application until, or after,
crop emergence.
-
Weeds in fields, alleys and
roadways are prevented from going to seed.
-
Scouting of fields in midseason
for weeds. Location and species of uncontrolled
weeds are mapped and the information is used in planning for
next year.
-
Outbreaks of new or problem weed
species are controlled, using chemical or
non-chemical means, to prevent spreading or seed production.
-
Trial plot is maintained to test
a different weed management technique.
-
Plan for healthy crop of potato
Check List of
Control Measures
In order to manage a potato crop in a state of
optimal health, it is necessary to understand that constitute
a healthy potato plant. The potato is a member of the plant
family Solanaceous, which also include tomato, egg plant and
tobacco as well as weed such as nightshade, groundcherry and
buffalo bur. Unlike these other crop, however, potatoes are
not produced from true seeds but rather are grown vegetatively
from tubers “ seed pieces (Fig 4). It is convenient to divide
the growth and development of the potato plant into five
distinct life stages.
Fig 4: A potato plant
developing from a seed piece cut from a tuber. Tubers develop
from the enlarge tips of stolons (underground stem). Tubers
have eyes (dormant buds), which can develop into shoots and
lenticels (pores), through which air penetrate to interior
tissues.
The Year Prior
to Growing Potatoes
·
Select cultivars appropriate for intended
markets and production conditions. Identify reputable seed
potato growers and visit forms to examine seed lots and
certification records. Arrange for delivery of high quality
certified seed potatoes.
·
Establish an appropriate long-term crop
rotation, with potatoes grown no more often than every third
year. Use rotation that suppresses diseases and insects and
nematodes pests, and implement rotation-wide weed control
strategies. Destroy volunteer potatoes and weed that may
harbor diseases or insect pests.
·
Analyze the soil hardness, irrigation, diseases
and weeds of potato. Fumigate the soil and spray some
pesticides. Add some nutrients for the balance of soil pH and
add some nutrients in soil.
Prepalnt
·
Collect and analyze soil samples for fertility,
pH and other pertinent factors. Apply preplant fertilizers and
soil amendments as indicated by the results of soil analysis.
Establish permanent records of fertility, rotation, cultural
management and pesticide use for each field.
·
Perform tillage operations necessary to manage
weeds and crop residues, minimize erosion, and provide tilth
for planting. In irrigated production, establish sufficient
soil moisture in the root zone to provide adequate available
water until the potato plants are fully emergence.
·
Properly dispose of waste potatoes left from
previous crop- never in cull piles.
·
Clean and sanitize storage facilities and
seed-handling equipment prior to receiving seed potatoes.
·
Examine seed tubers for diseases and defects
upon delivery. Handle and store seed properly to maintain
tuber health. Do not hold seed in storage areas that have been
treated with a sprout inhibitors and may still be
contaminated.
Fig 5:
Potato development.
Planting
·
Manage seed-cutting and healing operations
carefully to ensure healthy, uniform, properly sized pieces.
Sanitize cutting equipment at least daily and before cutting
each seed lot. Apply a seed piece fungicide treatment as
needed. Provide conditions for cut seed to suberize properly,
or plant immediately after cutting, when soil conditions
permit.
·
Delay planting until soil temperatures are
above 50F. As much as possible, schedule planting operations
to coincide with favorable soil conditions and weather.
Operate the planter so that the seed pieces are planted at the
intended spacing at a depth that will ensure rapid emergence.
Apply fertilizers and pesticides as appropriate.
Growth Stage
1: Preemergence
·
Perform operation for preeemergence weed
control and any practice hat reduce soil crusting and promote
rapid emergence.
·
In irrigated production, do not water prior to
emergence unless the soil becomes excessively dry at the depth
of the seed pieces.
Growth Stage II: Vegetative Growth
·
In irrigated production, provide uniform soil
moisture and avoid especially wet of dry soil.
·
Apply post emergence herbicide as appropriate.
Complete hilling-cultivating operations well before row
closure, and avoid root pruning during tillage. Apply
fertilizer side-dressings prior to the last hilling.
·
Being insect scouting and disease monitoring.
Delay the first insecticide or fungicide application until the
action threshold for the target pest or diseases has been
reached (Fig 6).
Fig 6: Growth
stage of potato.
Growth Stage
III: Tuber Initiation
·
Avoid especially wet or dry soil, to minimize
the development of common scab and tuber disorders.
·
Begin petiole analysis for nutritional
management, if appropriate.
·
Continue insect scouting and disease
monitoring, and apply pesticides as needed.
Growth Stage
IV: Tuber Bulking
·
In irrigated production, maintain uniform
adequate soil moisture. Avoid overwinterinbg, to minimize
disease development and nitrate leaching. Apply nutrients
through sprinklers, if appropriate.
·
Continue insect scouting and disease
monitoring, and apply pesticides as needed.
·
If desired, apply sprout inhibitors to plants
when most tubers are at least 2 inches in diameter.
Growth Stage
V: Tuber Maturation
·
Reduce irrigation to promote tuber skin set,
minimize tuber disease, and manage late-season weed growth.
·
Cease application of nitrogen in irrigation
water 4-6 weeks before vine killing. Schedule vine-killing
operation to allow complete desiccation of the vines before
harvest. Continue foliar applications of fungicide and
insecticide, if appropriate, until the vines are completely
dead.
·
Inspect, repair, and sanitize storage
facilities and harvest equipment. Make necessary modification
to harvest equipment to minimize bruising.
Harvest
·
Train personnel for a safe. Low-bruise harvest.
Conduct all harvesting, transportation, and bin-loading
operations with bruise management as a primary goal. Ensure
that tubers are not dropped from height of more than 6 inches.
·
Begin harvesting after the vines are completely
dead, early enough in the season to avoid from damage.
Coordinate harvest operation with current and expected weather
conditions, so that tubers are dug when conditions are as
close as possible to optimal (60-65% of available soil water
and tuber pulp temperatures of 50-65F.)
·
Remove as much soil and debris as possible from
tubers during harvest.
·
Trap loads in the field to protect harvested
tubers from rain, direct sun, and adverse temperatures.
Isolate damaged or diseased lots in separate bins for
immediate grading and marketing.
Storage
·
Manage the curing period carefully to provide
appropriate conditions for wound healing (50-60F), relative
95-99%, and good air movement).
·
Monitor air movement, humidity, and temperature
throughout the pile, and maintain the environmental conditions
appropriate for each stage of the storage and on tubers.
Continually monitor the pile for any signs of decay, and take
appropriate action if decay develops.
·
If appropriate, have a chemical sprout
inhibitor applied by a custom application after the curing
process has been completed.
·
Before removing tubers for marketing, warm the
store age to raise pulp temperatures above 50F. Manage
bin-unloading operations to minimize bruising, following the
same principles applied at harvest.
·
Ensure that washed or flumed potatoes are well
dried before packing. Use ventilated bags.
·
Dispose of waste potatoes properly-never in
cull piles.
Integrated
Management of Potato Crop
11.
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