Crop rotation refers to growing different crops in succession on the same piece of land. It helps maintain soil fertility through legumes that fix nitrogen. Crop rotation provides various benefits like increased yields, reduced costs from weeds and pests, and regular income. Principles of effective crop rotation include adapting to soil and climate, maintaining soil organic matter, and rotating between deep and shallow root crops. Other cropping systems discussed are intercropping, mixed cropping, relay cropping, and monocropping.
2. Crop Rotation
• It refers to recurrent succession of crops on the
same piece of land either in a year or over a
longer period of time.
• It is a process of growing different crops in
succession on a piece of land in a specific
period of time, with an objective to get
maximum profit from least investment without
impairing the soil fertility.
1
3. • In the rotation of crops, leguminous crops like pulses,
beans, peas, groundnut and Bengal gram are sown in-
between the seasons of cereal crops like wheat, maize and
pearl millet.
• The leguminous plants are grown alternately with non-
leguminous plants to restore the fertility of the soil. When
the cereal crops like rice, wheat, maize are grown in the
soil, it uses up a lot of nitrogenous salts from the soil. If
another crop of cereal is grown in the same soil, the soil
becomes nitrogen deficient. So by rotation a leguminous
crop is grown. There plants have the ability to fix
atmospheric nitrogen to form nitrogen compounds
through the help of certain bacteria present in their root.
These nitrogen compounds go into the soil and make it
more fertile.
5. 1) It should be adaptable to the existing soil, climatic and
economic factors.
2) The sequence of cropping adopted for any specific area
should be based on proper land utilization. that can be
maintained yields and reduced soil erosion.
3) The rotation should contain a sufficient acreage of soil
improving crops to maintain and also build up the OM
content of the soil.
4) In areas where legumes can be successfully grown, the
rotation should provide for a sufficient acreage of legumes
to maintain the N supply of the soil.
Characteristics of Crop rotation
or Principles of Crop rotation:
4
6. 5) The rotation should provide roughage and pasturage
for the live stock kept on farm.
6) It should be so arranged as to help in the control of
weeds, plant disease & insect-pests.
7) The rotation should be arranged as to make for
economy in production & labour
utilization exhaustive (potato, sugarcane) followed by
less exhaustive crops (oilseeds & pulses)
8) The crops with tap roots should be followed by those
which have fibrous root system. This helps in proper &
uniform use of nutrients from the soil & roots do not
compete with each other for uptake of nutrients.
7. 9) The selection of crops should be problem and need/demand
base.
i) According to need of people of the area & family.
ii) On slop lands alternate cropping of erosion promoting and
erosion resisting crops should be adopted.
iii) Under Dryland or limited irrigation, drought tolerant crops
(Jowar, Bajra), in low lying & flood prone areas, water
stagnation tolerant crops (Paddy, Jute) should be adopted.
iv) Crops should suit to the farmer’s financial conditions, soil
& climatic conditions.
10) The crops of the same family should not be grown in
succession because they act like alternate hosts for insect
pests & disease pathogens and weeds associated with crops.
8. Advantages of Crop Rotation
1. There is an overall increase in the yield of crops due
to maintenance of proper physical condition of the
soil and its OM content.
2. Rotation of crops helps in saving on nitrogenous
fertilizers, because leguminous plants grown during
the rotation of crops can fix atmospheric nitrogen in
the soil with the help of nitrogen fixing bacteria.
5
9. 3. Rotation of crops help in weed control and pest
control. This is because weeds and pests are very
choosy about the host crop plant, which they attack.
When the crop is changed the cycle is broken.
Hence, pesticide cost is reduced.
4. There is regular flow of income over the year.
5. Proper choice of crops in rotation helps to prevent
soil erosion.
6. It supplies various needs of farmer & his cattle.
7. Crop rotation adds diversity to an operation.
‘The supervisory work also becomes easier.”.
11. Type Rotations
One-year rotation
1. Maize mustard
2. Rice-wheat
Two-year rotation
1. maize-mustard-sugarcane-fenugreek (methi)
2. Maize-potato-sugarcane-peas
Three-year rotation
1. rice-wheat-mung-mustard-sugarcane-berseem
2. Cotton-oat-sugarcane-peas-maize-wheat
Selection of crops for rotation
Vegetables and flowers are grown in areas close to the cities for
higher income.
12. Mixed Cropping or Crop Mixtures
It is the process of growing two or
more crops together in the same
piece of land simultaneously. The
cereals are usually mixed with
legumes viz.
Jowar or Bajara mixed with Tur,
udid, Green gram, Black gram, Gran.
Wheat is mixed with peas, gram
or mustard.
Cotton is grown mixed with Tur or
sunflower.
6
7
13. Objectives
1) To get handy installments of cash returns especially in
irrigated crops,
2) To achieve better distribution of labour throughout
the year,
3) To utilize available space & nutrients to maximum
extent possible,
4) To safe guard against hazards of weather, diseases &
pests,
5) To secure daily requirements like pulses, oilseeds,
fibers, etc.
6) To get balanced cattle feed.
14. In order to obtain the maximum benefit from
the subsidiary crop mixed with the main crop, it
should have the following characteristics:
i) Not abstract the growth of the main crop,
ii) Mature earlier or later than of the main crop,
iii) Preferably be a legume,
iv)Have diffifferent growth habits & nutrient
requirements,
v) Have different rooting depths & ramification
vi) Not be very exacting in climatic requirements.
15. Companion Crops: Different crops are sown in different
rows. E.g.: 6 to 8 rows of cotton + 2 to 3 lines of Tur, 4 – 6
rows of Jowar + 1 – 2 lines of Tur, Jowar + Mung/Urd,
Jowar + Safflower.
i) Guard crops: Growing hardy or thorny crops
(Mesta/Safflower) around the main crop (Jowar/Wheat)
ii) Augmenting crops: Growing sub-groups
(augmenting) to maintain the yield of main crop.
Jowar/Bajara + Cowpea
8
16. Intercropping:
• Growing of two or more crops simultaneously on
the same piece of land (field). There is a crop
intensification in both time and space
dimensions. There is intercrop competition
during all or part of crop growth.
9
17. Advantages of Intercropping
• Better use of growth resources including light, nutrients
and water.
• Suppression of weeds
• Reduced plant and disease incidence
• Yield stability
• Ecological stability i.e. improvement of soil health and
agro-ecosystem
• Other e.g. Physical support of one crop to another and
home gardening leading to a more puriform food supply
is a good example of realization of intercropping
advantages.
18. • Labour intensive
• Control of pests and diseases or chemical
weed control may be difficult
• Mechanisation is difficult to realize
• Disadvantages caused by adverse competitive
effects or by allelopathy
Disadvantages of intercropping
19. Difference between –
Inter Cropping & Mixed Cropping
Sr. No Inter Cropping Mixed Cropping
1
The main object is to utilize the
space left between two rows of
main crop
To get at least one crop under
favourable conditions
2
More emphasis is given to the
main crop
All crops are cared equally
3
There is no competition between
both crops
There is competition between all
crops growing
4
Inter crops are of short duration
& are harvested much earlier
than main
The crops are almost of the same
duration
5
Sowing time may be same or
different
It is same for all crops
6
Crops are sown in different rows
without affecting the population
of main crop when sown as sole
crop
Either sown in rows or mixed without
considering the population
20. It refers to planting of succeeding crop before harvesting the
preceding crop like a relay race where a crop hands over the land
to next crop in quick succession.
Relay Cropping:
10
21. • Advantages:
• 1. Getting one time more production, suitable for mono
cropped zones( like Sundarban regions ).
• 2. No plowing required. Save a lot of money.
• 3. Less amount of water is needed, environment friendly
farming technique.
• 4. Increase soil fertility through nitrosomonas bacteria.
• Disadvantages:
1. Required 20% more seeds than usual.
2. As the plants grow zigzag, sometimes need more labour.
3. In some areas of sundarban it failed as there was no scope
for irrigation and there was no rain from Sept-march.
22. Ratoon cropping or rattooning
• It refers to revising a crop
with regrowth coming out
of roots or stalks after
harvest of the crop.
E.g.: Sugarcane or Jowar
rattooning.
11
23. Alley cropping
• is the cultivation of food, forage or specialty crops between rows
of trees. It is a larger version of intercropping or companion
planting conducted over a longer time scale. Alley cropping can
provide profitable opportunities for row crop farmers, hardwood
timber growers and nut growers
24. Monocropping or monoculture,
It refers to the presence of a single crop in a
field. This term is often used to refer to
growing the same crop year after year in the
same field; this practice is better described as
continuous cropping, or continuous
monocropping.
25. • Two or more crops are grown on the same
field in one year. Intensification of cropping is
in temporal and spatial dimension.
Multiple cropping:
Sequential cropping:
Growing two or more crops in sequence on the same
field in a year. The succeeding crop is sown /planted
after the preceding crop has been harvested. Crop
intensification is only in time dimension and there is no
intercrop competition.
26. Some variations of sequential cropping are
• Double cropping (sequential cropping ):
Growing two crops per year in sequence. is the practice of
planting a second crop immediately following the harvest of a
first crop, thus harvesting two crops from the same field in
one year. This is a case of multiple cropping, which requires a
season long enough and crops that mature quickly enough to
allow two harvests in one year
• Triple cropping:
Growing three crops per year in sequence.
• Quadruple cropping:
Growing four crops per year in sequence.
• Relay cropping:
A significant part of the life cycle of the, second crop overlaps
with the cropping cycle of the first crop.