2. 1. National Research Centre on Integrated Farming at East Champaran
District, Bihar.
2. ICAR- Indian Institute of Farming Systems Research at Modipuram, U. P.
In India, there are two institutes working on cropping system:
3. • It is defined as the order in which the crops are cultivated on a piece of land over a fixed
period, say a year
• In cropping systems, sometimes a number of crops are grown together or they are grown
separately at short intervals in the same field
• Historically, cropping systems have been designed to maximize yield, but modern agriculture
is increasingly concerned with promoting environmental sustainability in cropping systems
Cropping System
4. The objective of any cropping system is efficient utilization of available resources
viz. land, water and solar radiation
The objective of traditional agriculture was to increase the production by two
means:
a. by increasing area under cultivation
b. by increasing the productivity per unit area of the crop
However, two more dimensions have been added to modern agriculture:
a. to increase the production per unit time.
b. to increase the production per unit space.
5. Basic principles of cropping systems
Choose crops that
• complement each other
• utilizes available resources efficiently
• maintain and enhance soil fertility
• have a diversity of growth cycle
• keep the soil covered
• Strategically plan and modify the cropping system as needed
6. Classification of Cropping System
Depending on the resources and technology available, different types of cropping systems
are adopted on farms, which are as below
Single Cropping:
A single crop is grown on a piece of a land e.g. linseed. It is also known as solid planting.
Predominant single/mono crops in drylands - Sorghum and finger millet
7. Poly-cropping:
Growing two or more crops on the same field in a year.
Annual and perennial plants can be organized in fields together
It includes inter-cropping, mixed cropping and sequence cropping
8. Inter-cropping:
Growing two or more crops simultaneously on the same field during year.
It is further sub-divided as:
(a) Mixed intercropping
(b) Strip intercropping
(c) Row intercropping
(d) Relay intercropping
9. Mixed intercropping:
Growing two or more crops simultaneously with no distinct row arrangement.
Also referred to as mixed cropping. Ex: Sorghum, pearl millet and cowpea are mixed and
broadcasted in rainfed conditions.
Strip intercropping:
Growing two or more crops simultaneously in
strips wide enough to permit independent
cultivation but narrow enough for the crops to
interact agronomically. e.g. Maize + cowpea
(2:4) strip.
10. Row intercropping:
Growing two or more crops simultaneously where one or
more crops are planted in rows. Often simply referred to as
intercropping. e.g, Maize + blackgram
Relay intercropping:
A second crop is sown after the first crop has reached its reproductive stage of growth, but, before it
is ready for harvest. Often simply referred to as relay cropping.
Famous by local names as
*Paira cropping: UP, Bihar *Utera cropping: MP
*Lathyrus and lentil are generally sown as relay crops
11. Sequential cropping
Growing two or more crops in sequence on the same field in a farming year
The succeeding crop is planted after the preceding crop has been harvested
There is no intercrop competition
Double cropping: Growing of two crops in a year in sequence
Triple cropping: Growing of three crops in a year in sequence
Quadruple cropping: Growing of four crops in a year in sequence
12. The plant characteristics that influence cropping systems are: Plant height,
crop canopy, nutrient & water requirements, root structure and plant products
Farm sustainability depends on the efficient use of natural resources (soil,
water, energy, and plant diversity) depending on the requirements of the
farmers
A sustainable system aims to optimize the production rather than
maximizing it
13. Cropping System Approach in
Integrated Pest Management (IPM)
• Green revolution made India from a grain deficient nation to a food security for most of
the people
• In spite of the wide spread use of synthetic pesticides and other control measures, the
losses due to insect and pests increased in post-green revolution era than in pre-green
revolution era
• Overall, the losses increased from 7.2 per cent in early 1960s to 23.3% in early 2000s.
The maximum increase in loss occurred in cotton (18.0 to 50.0%), followed by other
crops like sorghum and millets (3.5 to 30.0), maize (5.0 to 25.0) and oilseeds (5.0 to 25.0)
(Dhaliwal et al., 2007)
14. • In Vision-2050 of IARI and ICAR both, emphasis has been given on crop diversification,
polyculture and cropping system as pest management strategies
• Among these, cropping system found to be promising
• Multiple cropping - Intercropping, Mixed cropping, Sequence cropping, Relay, Multi-
story/tier are encouraged
15. • Crop diversification hypothesis
1. Trap crop hypothesis suggests that pests will be attracted to associated plants and
hence are less likely to leave the trap crop and wander into the principal crop
(Vandermeer, 1989)
2. Natural enemy hypothesis proposes that a lower number of phytophagous insects are
found in complex environments because predators and parasitoids are more diverse
and abundant in those environments compared to simple environments (Root, 1973;
Russell, 1989)
16. 3. Barrier crop (physical obstruction) hypothesis bases its effectiveness on the use of taller
non-host plants to obstruct the movement of the pest insect within the cropping system
(Perrin and Phillips, 1978)
4. Visual camouflage “apparency” hypothesis also known as the “apparency hypothesis”
incorporates the visual stimuli that induce herbivores to land on plants based on colour
and plant height. Herbivores tend to land on tall green plants, so that using non crop
plants to make the crop “less apparent” by adding greener or taller plants is a useful
mechanism to camouflage the crop (Finch and Collier, 2000)
17. Cropping system helps in pest management by the following two latest approaches:
a) Top-down approach: This will act on pest by attracting, supporting and conserving
natural enemies of pest. This is an indirect way of reducing pest population.
b) Bottom-up approach: This will help in managing pest directly.
A. Top-down approach includes
• Banker Plants
• Insectary Plants
B. Bottom-up approach includes
• Indicator
• Barrier
• Repellent
• Trap
18. Top-down approaches:
Banker plants
Banker plants consist of a non-crop host plant harboring a natural enemy
The goal of banker plants is to sustain a reproducing population of natural enemies that
will provide long-term pest suppression within a crop system
Parasitoids reproduce in hosts that live on the banker plant, which guarantees ongoing
release of natural enemies, enabling long-term pest suppression
Banker plant systems have been used mainly to target aphids, but they are also used
against spider mites and thrips
19. Parasitic Wasps
An example of a commercially available banker plant system includes a parasitoid and aphid
prey for controlling the green peach aphid, Myzus persicae (Figure 1) and cotton melon
aphids, Aphis gossypii (Figure 2). These are two of the most commonly encountered pest
aphids in greenhouse production systems
(Figure 1) (Figure 2)
Types of banker plant systems
20. The system targeting these pests consists of bird cherry-oat aphids, Rhopalosiphum padi
(Figure 3) reared on winter wheat or barley, serving as alternative prey for the beneficial
parasitoid, Aphidius colemani (Figure 4)
(Figure 3) (Figure 4)
21. The parasitic wasp (fig. 4) seeks out and attacks individual aphids, parasitizing them by
laying an egg within their bodies. Upon hatching, the wasp larva consumes its aphid host
from within and eventually completes its development. When the larva pupates, the aphid
swells in size, hardens and turns brown, resulting in what is called a “mummy” (Figure 5).
The adult wasp eventually emerges from the mummy through a smooth, round exit hole
(Figure 5)
Banker plant colonies in screen cages
consisting of bird cherry oat aphid on
immature winter wheat
22. Steps to implement the A. colemani/R. padi system:
1. Purchase winter wheat seed and R. padi, as well as two separate enclosures. Butterfly cages are ideal
2. Sow wheat seed in several 6- to 10-inch pots (two to three pots per 1,000 square feet of growing space)
3. Once the wheat is sprouted, infest the plants with purchased bird cherry-oat aphids
4. Keep the plants moderately moist and cool
5. After few days, place half the R. padi-infested plants into a separate cage (heavily infested)
6. Make sure the plants have adequate moisture
7. Add A. colemani mummies to one cage by sprinkling the mummies onto wheat plants
8. Aphidius colemani adults will emerge from the purchased mummies in 24 to 48 hours and parasitize the R.
padi aphids on wheat
9. Seven to 10 days after placing the mummies, new mummies will be formed on the plant. These are your
banker plants. (Leave at least one plant in the cage for future colonies.)
10.Place banker plants among the crop in the greenhouse. Begin with one to two banker plants per 2,000 to
5,000 square feet.
23. Predatory Mites
• These can be reared on pollen plants in banker plant systems designed to control pest
mites, thrips and other pests. Banker plants used in these systems include castor bean,
corn and ornamental peppers.
• As mites cannot fly, banker plant foliage must overlap or touch crop foliage to facilitate
their movement among infested crop plants. Colonies of predatory mites can be
maintained by the grower, and banker plants should be populated with mites a few days
before or at the start of the crop cycle. This mean infesting banker plants with mites weeks
or months before moving the plants into the greenhouse alongside crop plants (Miller et al.
2017).
24. Types of banker plant systems
Type Name Alternative Prey Alternative Plant Pests Attacked
Parasitic Wasps
Aphidius colemani bird cherry-oat aphid
winter wheat, barley,
millet
cotton melon aphid,
tobacco aphid
Aphelius abdominalis
bird cherry-oat aphid,
English grain aphid
oat
potato aphid, green
peach aphid
Predatory Mites
Ambyseius andersoni pollen
castor bean, corn,
ornamental pepper
spider mites and other
mites
Ambyseius californicus pollen corn
two-spotted spider
mite, carmine mite
Ambyseius degenerans pollen castor bean thrips
(Miller et al. 2017)
25. Insectary plants
• Insectary plants are introduced into agricultural or horticultural systems to increase the
amounts of nectar and pollen resources required by some natural enemies of pests
• They attract beneficial insects, such as parasitoid wasps and predatory flies, with
extrafloral nectaries or flowers with readily accessible pollen and nectar which are not
otherwise available in a monoculture
• In a research study, the insectary plants like sweet alyssum (Lobularia maritima) and
licorice mint (Agastache foeniculum) increased the lifespan of key parasitoid wasps which
relied on a regular supply of carbohydrates from the plants (Osborne et al., 2005)
26. Bottom-up Approaches:
• Indicator plants
• In the context of integrated pest management (IPM), Lamb (2006) describes indicator plants as
species or varieties that are more prone to an insect or disease than the crop
• They attract the pests and make it easier to detect the presence of pests and pathogens
• Examples of typical indicator plants are tomatoes or eggplants which can be used to indicate
whitefly infestation in poinsettia crop. Tomatoes may draw whitefly out of poinsettias, thus
enhancing their detection and also intercepting them
• French bean plants Phaseolus vulgaris, have been found to be indicator plants for the carmine
spider mite (Tetranychus cinnabarinus) attacks on greenhouse tomatoes. The pest becomes
established 5 weeks beforehand on beans, then on tomatoes, thus providing enough time to
order and distribute natural enemies for spider mite control on tomatoes
27. Barrier plants
• These are used within or bordering a primary crop for the purpose of disease suppression
and/or interception of pests and/or pathogens
• Sometimes, a non-susceptible crop can be grown as barrier with the crop to be protected, so
that the later ones can provides camouflage, decreases the movement and spreading. It may
also act as a source of natural enemies
• Examples of barrier plants are sorghum and pearl-millet are used to protect sunflower,
safflower etc.
28. Trap plants
• Trap plants are plant stands that are deployed to attract, divert, intercept, and/or retain
targeted insects or the pathogens in order to reduce damage to the main crop. Eggplants
can act as trap plants for whitefly
• The ‘‘push–pull strategy’’ warrants special mention here. Pests are repelled from the crop
(‘‘push’’) and attracted into trap plants (‘‘pull’’). The push– pull strategy can provide a
consistently positive effect on crop yield
• An example is one implying lepidopteran pests on maize and other cereals in Africa. With
the aid of molasses grass (Melinis minutiflora, Poaceae) (push) and the trap Napier grass
(Pennisetum purpureum, Poaceae) (pull), stem borers (Chilo partellus, Crambidae) were
reduced and significant higher yields were produced per unit area. As a side benefit, the
repellent and trap plants were valuable forage for farm animals (Khan et al., 2006)
29. Repellent plants
• A repellent plant is an intercropping culture which repels pests and/or pathogens because
of the chemicals emitted by these plants
• The repellent plant hypothesis proposes that a mixed plant stand can contain some
unpalatable or repellent plant species that hinder the ability of the herbivore to utilize its
normal food
• Many plants contain natural substances in their roots, flowers, stems, or leaves, which can
either repel or attract insects. A wide range of natural chemicals (e.g. alkaloids, terpenoids,
flavonoids, quinones) synthesized by plants for instance lemon grass (Cymbopogon
citratus) has been shown to be effective in controlling many crop insect pests and
diseases
30. Aziz et al. 2011 conducted an experiment at Bogor, Indonesia to study the effect of
repellent plants on organic vegetable soybean production. The organic experiment was
arranged in a split plot design using four species of companion plants as repellent plants,
i.e. Tagetes erecta (Mexican marigold), Cymbopogon nardus (Citronella), Ocimum
gratissimum (Basil) and Tephrosia vogelii (Fish poison bean) and without repellent plants
as the main plot, and seed treatments i.e. galangal oil, Pseudomonas fluorescens, and
without seed treatments as sub plot using 3 replications and conventional system (using
pesticides) as control
31. Table 1. Percentage insect infested plants and disease prevalence as affected by repellent
plants and seed treatments
Treatments Percentage of insect infested plants
(%)
Disease prevalence (%)
6 WAP 7 WAP 8 WAP 6 WAP 7 WAP 8 WAP
Organic system
Repellent plants
Tagetes erecta 27.56 35.11 37.67b 17.78 22.33 31.56
Cymbopogon nardus 32.67 37.44 40.33b 19.44 24.78 35.89
Ocimum gratissimum 26.67 32.78 35.67b 19.22 29.56 36.22
Tephrosia vogelii 28.78 35.11 38.11b 23.67 30.89 36.11
Without repellent plants 30.22 41.00 50.56a 22.11 27.00 38.67
Seed treatments
Galangal oil 29.33 35.60 40.27 19.07 25.00 35.47b
P. fluoresecens 30.53 37.73 41.07 21.07 28.93 33.87b
Without seed treatments 27.67 35.53 40.07 21.20 26.80 37.73a
Conventional system 19.17 22.92 32.50 9.17 11.42 14.42
Note: Numbers followed by the same letter in the same columns are not significantly different based on DMRT at level α = 5%; WAP = Week After Planting
J. Agron. Indonesia 39 (1) : 13 – 18
Aziz et al. 2011
Bogor, Indonesia
32. Table 2. Effect of repellent plants and seed treatments on percentage of insect infested
plants at 6 WAP (%)
Treatments Galangal Oil P. fluorescens Without seed treatments
Repellent plants
Tagetes erecta 28.67ab 33.33a 20.67bc
Cymbopogon nardus 30.67ab 34.33a 33.00a
Ocimum gratissimum 28.33ab 28.67ab 23.00bc
Tephrosia vogelii 27.33ab 29.67ab 29.33ab
Without repellent plants 31.67a 26.67ab 32.33a
Conventional system 19.17
Bogor, Indonesia
J. Agron. Indonesia 39 (1) : 13 – 18
Aziz et al. 2011
Note: Numbers followed by the same letter in the same columns are not significantly different based on DMRT at level α = 5%; WAP = Week After Planting
33. Organic plots yields (4.81-5.79 kg plot-1); plot size (5.0 x 2.5m) were lower than those
in the conventional plots (6.70 kg plot-1); this might be related to the lower nutrient
availability on the organic plots from manure and green manure applied to the organic
plots. In addition, decomposition of these organic materials might still occur during the
experiment and further reduced the nutrients availability for the soybean plants. The
low CEC on the organic matter because of the incomplete decomposition process
also caused the lower nutrient availability
34. In another study, Iamba and Homband 2020 performed an experiment at University of Natural
Resources and Environment campus in East New Britain, Papua New Guinea to study the effect of
intercropping of Pak choi (Brassica rapa chinensis) with Marigold flower (Tagetes erecta L.) and Onion
(Allium cepa L.) to control foliar pests. In this study, two (2) repellent plants, Marigold flower (Tagetes
erecta L.) and Onion (Allium cepa L.) were intercropped with Pak choi (Brassica rapa chinensis) in an
attempt to lower pest abundance. The marigold intercrop was found effective in lowering the population
of two common cabbage pests, Plutella xylostella and Psylliodes chrysocephala. Onion intercrop and
control treatment (sole Pak choi) did not show any significant differences in relation to pest suppression.
The study highlights that marigold (T. erecta) is an effective plant with active volatiles that attracts
natural enemies to lower pest population (Bhattacharyya 2017; Khan et al. 2016). It is an important plant
that maintains a high natural enemy biodiversity. Intercropping of marigold plants with Pak choi crop
provides an eco-friendly strategy to reduce pest population.
35. CONCLUSIONS
• Cropping system has so many advantages over other pest management strategies such
as resistant pest management, pest suppression, increase biodiversity, usually support
lower specialized herbivore loads than do monocultures
• A good cropping system needs proper understanding of nature of pest, crop to be rotate
should be non-host, intercropping (no competition for resources), understanding
interaction of crop-pest and secondary plant
• With increasing demand in global crop production and quality, while reducing negative
environmental effects, sustainable cropping systems needs to be exploited from the
viewpoint of integrated pest management
36. References
• Aziz S.A., Pardiyanto A.Y. and Sinaga M.S. 2011. Repellent Plants and Seed Treatments for
Organic Vegetable Soybean Production. J. Agron. Indonesia 39 (1) : 13 – 18. Dhaliwal, G. S.,
Dhawan, A. K. and Singh, R. (2007). Biodiversity and ecological agriculture: Issues and
perspectives. Indian Journal of Ecology, 34 (2): 100-108.
• Bhattacharyya M. (2017). The push-pull strategy: A new approach to the eco-friendly method of
pest management in agriculture. Journal of Entomology and Zoology Studies 5(3):604-607.
• Finch, S. and Collier, R.H. (2000). Host-plant selection by insects - a theory based on
‘appropriate/inappropriate landings’ by pest insects of cruciferous plants. Entomologia
Experimentalis et Applicata, 96 (2): 91-102.
• Iamba K and Homband V. (2020). Intercropping of Pak choi (Brassica rapa chinensis) with
Marigold flower (Tagetes erecta L.) and Onion (Allium cepa L.) to control foliar pests. Journal of
Entomology and Zoology Studies 8(6): 731-737.
37. • Khan, Z. R, Midega, C. A. O, Hutter, N. J.,Wilkins, R. M. and Wadhams, L. J. (2006).
Assessment of the potential of Napier grass (Pennisetum purpureum) varieties as trap
plants for management of Chilo partellus. Entomologia Experimentalis et Applicata,. 119:
15-22.
• Khan Z et al. (2016). Push-pull: chemical ecology-based integrated pest management
technology. Journal of chemical ecology 42(7):689-697.
• Lamb, E. M. 2006. Indicator plants, trap crops, and banker plants: tools for greenhouse
IPM ornamental crops. IPM E-Newsletter; [cited (2012) Mar 29] Available from: http://
www.nysipm.cornell.edu/nursery_ghouse/newsletters/ indicator_trap_banker.ppt.
• Miller T.C., Rebek E and Schnelle M. 2017. Banker Plants for Control of Greenhouse
Pests. Oklahoma Cooperative Extension Service. Oklahoma state university, USA EPP-
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control insects in greenhouse vegetables. Proceedings of the 118th Annual Meeting of the
Florida State Horticultural Society 118: 127-128.
• Perrin, R. M. and Phillips, M. L. (1978). Some effects of mixed cropping on the population
dynamics of insect pests. Entomologia Experimentalis et Applicata, 24(3): 585-593.
• Ridray, G., Bonato, O. (2008). Decision making in integrated pest management for tomato
protected crop. EWS3 – 3rd European Whitefly Symposium, Oct 20–24, 2008, Aguadulce,
Spain.
• Root, R. B. (1973). Organization of a plant-arthropod associations in simple and diverse
habitats: the fauna of collards (Brassica oleracea). Ecological Monographs, 43: 95- 118.
39. • Russell, E. (1989). Enemies hypothesis: a review of the effect of vegetational diversity on
predatory Insects and Parasitoids. Annals of the Entomology Society of America, 18 (4):
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• Vandermeer, J. (1989). The ecology of intercropping, Cambridge, UK, Cambridge
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