Summer ploughing improves soil structure due to alternate drying and
cooling. Soil permeability is increased by breaking the compacted layers.
Tillage improves soil aeration which helps in multiplication of micro
organisms. Organic matter decomposition is hastened resulting in higher
nutrient availability.
Increased aeration also helps in degradation of herbicide and pesticide
residues and harmful allelopathic chemicals exuded by roots of previous
crop or weed. It also helps in reducing the soil dwelling insect pests.
In view of several benefits summer ploughing could be taken up at optimum
moisture level.
Frequent harrowing has to be avoided as it results in destruction
of soil structure. Tillage at improper moisture level is to be discouraged
as it also damages soil structure and leads to development of hard pans.
Shallow Ploughing
It is generally followed by the most of the farmers repeatedly at
the same depth (12-15 Cm). As a result of this hard pans are created,
which inhibits the penetration of roots in deep rooted crops.
Eg: Cotton roots grow to a depth of 2 Mts. in deep alluvial soils
without any pans, when hard pans are present they grow only upto hard
pan (5 - 20 cm). But shallow ploughing is practiced to open the soil
crust to increase the receptivity of rainfall.
Puddling
" Making soil impermeable by manipulating and compacting it in standing
water, which reduces its apparent specific volume, thus facilitates
transplanting." As a result of puddling, an impervious layer is formed
below the surface which reduces deep percolation losses of water.
Levelling
Levelling is the tillage operation in which the soil is moved to a
establish a desired soil elevation stage. Due to levelling the use of
water and fertilizer efficiency increases effectively.
Harrowing
Harrowing is a secondary tillage operation which pulverizes, smoothens
and packs the soil in seed-bed preparation and control weeds.
Conservation Tillage
The main objective is to conserve soil and moisture .Conservation
tillage is an operation that is designed to maintain roughness of a
field surface and leave most of the previous crop residues on the surface
while providing a suitable seed-bed and weed control for the next crop.
This roughness reduces water run off and soil erosion.
Ridges and Furrows
A long, row ridge of earth with gently sloping sides and a shallow
channel along the upper side, to control erosion by diverting surface
run-off across the slope instead of permitting it to flow uninterrupted
down to slope.
EG: Sugarcane, Sunflower, Vegetable crops.
Bunding
It is the process of forming an artificial earthern embankment made
across slopping agricultural land to cut short lengthy soil slopes and
reduces run-off and erosion.
These bunds are also formed along the contours across the slope of
land in the low rainfall regions to conserve soil moisture.
Seeds are spread uniformly over well prepared land and is covered
by ploughing or planking. It is most primitive method of sowing crops.
The broadcasting has severaldisadvantages.
Seeds fall at different depths when broadcasted resulting in uneven
stand.
It requires more seed rate.
Seeds fallen deep in the soil may not germinate.
Due to broadcasting excess competition at certain areas and no competition
at all in other areas takes place in the field. So, yield returns will
be decreased.
Water use efficiency and fertilizer efficiency will be decreased.
There is no possibility of controlling weeds by inter cultivation.
Drilling
To overcome the problems of broadcasting drilling the seeds in lines
has come into practice. Weeds can be controlled economically by inter
cultivation in line sown crops. In addition, drilling or line sowing
facilitates uniform depth of sowing resulting in uniform crop stand.
Seed rate can be considerably reduced drilling.
Planting
When individual seeds or seed material is placed in the soil by manual
labour, it is called planting.
Generally crops with bigger sized seeds and those needing wider spacing
are sown by this method. Eg : Cotton, Maize, Potato, Sugarcane, etc.
Transplanting
It is the process of planting seedlings in prepared main field. Small
seeded crops like Tobacco, Chillies, Tomato, etc. are to be sown shallow
and frequently irrigated for proper germination. Taking care of the
germinating seed or seedlings which are spread over large area is a
problem with regard to application of water, weed control, pest control
etc. Therefore, seeds are sown in a small area called nursery and all
the care is taken to raise the seedlings.
The advantages of transplanting saving in irrigation water, good
stand establishment and increase in intensity of cropping. In respect
to paddy the nursery is raised in small puddled plots and later transplanted
in the main field at required spacing.
Seed Rate
The quality of seed required for sowing in a unit area of land. It
is usually expressed in kg/ ha.
Spacing
The distance between crop row ( inter-row spacing) and between plants
within the row (intra - row spacing) is referred as spacing. It is expressed
in Cms.
Plant Population
Number of plants maintained in an unit area of land is known as plant
population/ density. Establishment of optimum plant population is essential
to get maximum yield. When sown densely competition among plants is
more for growth factors resulting in reduction of yield.
Yield per plant decreases gradually as plant population per unit
area is increased. The plant population density vary with the type of
soil and crop. Optimum plant population density has to be maintained
for securing maximum yield.
Nursery Raising
When more than one crop is to be grown in an year on the same piece
of land, the time occupied by each crop has to be reduced.
The seedling growth in the early stages is very slow. Seedlings need
extra care for establishing in the field because of their tenderness.
Small seeded crops are to be sown shallow and frequently irrigated for
proper germination.
Taking care of the germinating seed or seedlings which are spread
over large area is a problem with regard to application of water, weed
control, pest control etc. Therefore, seeds are sown in a small area
called nursery and all the care is taken to raise the seedlings.
Transplanting
Method
Transplanting is usually done manually. In case of rice it is also
done mechanically with transplantor provided the nursery is raised through
dapog method.
Time
For achieving good results from transplanting, the seedlings are to
be transplanted at optimum age and at proper depth. The age of seedlings
for transplanting depends on crop and seasonal conditions.
Equipment
For Sowing
Country plough (Akkadi), Seed drill, Ferti-cum-seed drill, Mechanical
seed drill are generally used.
It is an operation of soil cultivation performed in standing crop.
It is also called as inter culturing. It facilitates good aeration,
and better development of root system.
Weeding
Weeding is the process of eliminating competition of unwanted plants
to the regular crop in respect to nutrition and moisture. So that crops
can be grown profitably. It also facilitates other operations like irrigation
and fertilizer application. The advantages of weeding are
Conservation of soil moisture.
Reduced competition for nutrients and water.
Purity of seed can be maintained.
Earthing Up
It is the process of putting the earth or soil just near the base
for certain crops like Sugar cane, Cassava, Papaya, Potato, etc. to
give support to the plants.
Sugarcane, Papaya, Banana - To avoid lodging
Cassava, Potato - To provide more soil volume for the growth of tubers.
Vegetables - To facilitate irrigation.
Ridges and Furrows
It is also included in inter cultivation and generally done at the
base of the crop to provide extra support against lodging and also provide
soil volume for better growth. It also facilitates uniform spread of
moisture during operation of irrigation.
Other Operations
Certain other operations like gap filling, thinning and propping are
required as part of inter cultivation operations. In crops like Cotton,
Paddy, the gap filling is done in missing areas of the planted main
field to maintain optimum population .
Like wise thinning is also practiced in direct sown crops like Jowar,
Chillies, to avoid over crowding and to maintain uniform plant stand.
In crops like Sugarcane,betelwine, Grapes propping is necessary to support
the main crop establishment.
It is an operation of cutting, picking, plucking, digging or combination
of these for removing the useful part or economic end product, part
from the plant.
Time
Crops can be harvested at physiological maturity or at harvest maturity.
Crop is considered to be at physiological maturity when the translocation
of photosynthates are stopped to economic part. If the crop is harvested
early, the produce contain high moisture and more immature grains.
The yields will be low due to unfilled grains. Late harvesting results
in shattering of grains, germination even before harvesting during rainy
season and breakage during processing. Hence, harvesting at correct
time is essential to get good quality of grains and higher yields.
Methods
Harvesting is done by either manually or by mechanical.
Manually
Manual harvesting is practiced by cutting crop with sickle or knife.
In some crops like Sugarcane, Millets, Paddy the crop is cut with sickles
and knives.
In some crops like Groundnut, tuber crops the plants are pulled and
economic parts are separated. In other crops like Cotton, Chillies,
and fruits the picking is practices to remove the economic parts like
kappas, pods and fruits etc.
Mechanically
The combines are used to perform several operations such as cutting
the crop, separating the grain from straw, cleaning the grain from chaff
and transporting grains to the storage tank. Now a days the harvesting
is exclusively for harvesting crops like Paddy and threshing paddy are
used. Machines are now available for separating pods from the plants
and also for shelling pods (decorticators) in respect to Groundnut crop.
Likewise machines are available for threshing sunflower heads, shelling
of castor capsules and sowing of grain.
Drying and Processing
Drying is a process by which moisture content from grain is reduced
to safe limit. Drying is done either by using solar energy or by artificial
heating.
Processing is the conversion of the produce into a more finished
condition before it is offered for sale.
Cleaning
The removal of foreign and dissimilar material by washing, screening,
hand-picking, aspiration or any other mechanical means is known as cleaning.
It is required to maintain the quality of the produce.
Equipment
Harvesting:Sickle, knife, combines, harvesters
Threshing : Bullocks, Tractors, Decorticators etc.
After harvest of the crop, the remnants of the plant viz. Straw, stubbles,
leaves, etc. are ploughed into soil to decompose, there by providing
source of organic matter for the next season crop.
In some places the flock of sheep are housed (penning) during night
time. So that the excreta is collected on the field which is also a
good source of organic nutrients.
The left over stubbles, plant residues in crops like Cotton, Chillies,
Maize, Sunflower etc. may be burnt as part of soil sterilization as
to reduce population of harmful microbes and soil dwelling insect pests.
In crops like Paddy the stubbles may be removed by ploughing after
harvest to eliminate hibernating stem borer population. Field bunds
may be trimmed to avoid hibernating grass hopper egg masses.
