Timely land preparation can ensure planting at an optimal time.
Mobility and tillage depth depend largely on water management.
If the soil is kept wet and soft, then all
equipment – especially larger equipment - will tend to sink, create
problems of mobility and tillage depth.
When tillage layers are too deep then subsequent operations such as
walking, movement of power tiller or combine harvester can have problems.
Tillage can reduce weed burdens e.g., till on moist soil and re-till
after two weeks just prior to planting to kill germinating weeds.
Soil does not have to be saturated for residue to break down. Residue
decomposition is best at soil moisture levels of a moist but well drained
field (i.e., less than field capacity) or the
soil should be just wet.
Typical comparison of tillage systems and time required.
System
Hrs/ha
Animal
120-135
Hand tractor
40- 60
4 Wheel tractor
5 – 10
Two major systems of rice cultivation namely
Dry or upland system and
Wet system
are existing in all rice growing areas.
In upland system the crop is grown under rain fed conditions on dry
ground as in case of other cereals.
In wetland system the land is flooded and puddle where the crop is
grown in standing water from planting until near harvesting.
More specifically rice is cultivated in four systems like
Upland
Irrigated
Rain fed lowland and
Deepwater.
The land preparation varies with the system under which rice is cultivated.
a) Soils Suitable For Raising The Crop
Rice has been found to grow successfully under acidic as well as alkaline
soil reaction ranging between 3 pH in Kerala to as high as 10.5 pH in
northern parts of the country.
However, it has been observed that a soil having pH between 5 to 8.5,
soil conductivity below 4 m mhos/cm and exchangable sodium percentage
lesser than 15 may suit the crop to grow and produce well.
In India, rice is grown in a variety of soils like Alluvial soils,
Calcareous alluvial soils, Coastal and Deltaic Alluvials, Red soils,
Red and Yellow soils, Lateritic soils, Black soils, Red and Black soils,
Brown hill soils, Desert soils, Tarai soils, Saline-alkali soils, Peaty
and saline soils.
b) Summer Ploughing
In case of rice cultivation summer ploughing is resorted in the dry
and semi-dry system ( up land rice culture).
This system is mostly confined to the tracts which depends on rains
and with inadequate irrigation facilities .
In the semi dry system the rainwater is allowed to get accumulated
in the field when the crop is 5-6 weeks old.
In this system, a field is provided with deep summer ploughing at
40-45 days prior to the onset of monsoons.
Farm yard manure is evenly spread at 25-30 tons/ha and mixed well
into the soil. This system is prevalent in upland area of different
districts of Andhra Pradesh covering about 2 Lakh ha.
c) Preparatory Cultivation For The
Nursery
The next widely adopted system is irrigated system or otherwise known
as wet system.
In this system seedlings are raised in the nursery bed and later
transplanted in puddled mainfield.
The main object of raising seedlings is to obtain healthy planting
material, utilize the mainfield till the seedlings become ready,minimize
the cost by using less seed material etc.
Three methods are in vogue for raising seedlings and they are
Wet
Dry and
Dapog methods.
Of these the wet method is mostly adopted by rice growers throughout
the country.
Nursery bed preparation
The seed bed area is ploughed twice, either under dry & wet conditions,
and then puddled by giving two or three more ploughings.
Care is taken to see that a thinfilm of water is maintained in the
field, so that it does not dry up.
After ten days, the field is again ploughed twice and levelled. Usually,
well decomposed cattle manure or compost at the rate of eight to ten
tones per acre is applied at the time of the last ploughing.
If green leaf is available it is applied at the rate of 10,000 lb
per acre just after the second ploughing and buried in the soil.
Leaves decompose in about three weeks time, the field is repeatedly
ploughed to bring the soil into a soft puddle.
Under Indian conditions, heavy fertilization of the seed-bed is not
necessary, as this practice does not affect the yield of the crop.
However, where the seedlings are required quickly for planting, such
a fertilization of the seed-bed may be resorted.
When the field is brought to a fine soft puddle, it is divided into
small raised beds with 50cm. channel all around to facilitate drainage
and for even sowing of seed.
1) Wet Nursery
The area intended for nursery raising should have
An assured water supply and an efficient drainage system.
Should be dry ploughed for 2 times and later, it should be irrigated
and allowed to be wet for another two days.
Afterwards it should be puddled twice and the puddling may be repeated
after a gap of one week.
This process of puddling contributes in obtaining good tilth, removal
of weeds and also facilitates water retention.
Well decomposed farm yard manure at 5-8 tons per ha has to be applied
prior to dry ploughing.
To plant one acre, 4 cents of nursery is required.
Recommended inorganic fertilizers are to be applied after first phase
of puddling.
After levelling and final puddling, beds of convenient length with
width of 1.5m are to be made, leaving 50 cms channels in between two
beds.
2) Dry Nursery
In this method
The field is ploughed 5-6 times.
Beds of 1.5 m width and convenient length are to be prepared.
Channels are to be provided for irrigating and draining of the beds.
After preparing the beds they are to be wetted.
For 10 cents of nursery beds 500 kg of well rotten FYM, 1.25 Kg of
P205 and 1 kg of Potash need to be applied and
incorporated with spades.
3) Dapog Nursery ( Mat Nursery)
Features
Seed preparation
Soak the seeds for one day
Incubate the seeds for one day
Apply a seed rate of 50 kg/ha
Mat Preparation
Choose the suitable site for mat nursery
raising (preferably within or nearer to the main field) and puddle the
selected site.
Raise the puddled soil bed to a level of about 5 cm and level it properly.
To lay more than two rows of mats, select each bed width as 1.2m.
To cover one hectare of land selected plot should be of size of about
20 x 7.5m with provision of channels of width of 0.5m (See the figure
of mat layout).
Spread the plastic sheet evenly on the levelled and raised beds.
Mix the soil with FYM and water to prepare slurry.
Keep the DRR designed mat frame (having dimensions of 19 x 50 x2 cm
of each block) on the plastic sheet and spread the slurry mixture in
each block of the frame.
After proper settling, lift the frame to leave the mats behind. Each
time, five mats can be prepared this way.
Take 100-110 g of sprouted seed and spread it evenly on the prepared
mats and press them gently. One hectare of main field needs 500 – 600
mats.
The procedure is repeated to prepare all the mats. Spread either grass
or plastic sheet on the mats overnight and take it out in the morning.
Do not uncover if there is rain during the first week of mat raising.
Sprinkle with rose can on all the mats everyday to keep the mats moist.
After a week when the nursery looks green, provide water through channels
to the level just below the mats.
Apply fertilizer @ 30 g of DAP/ litre of water and sprinkle on the
mats with hand sprayer after 7-10 days of the nursery.
The nursery will be suitable for transplanting after 15-20 days when
the plant reaches height of 12-15 cm.
Seedlings raised by this method are very useful when mechanical transplanters
are used.
Preparatory Cultivation Of Main Field
The main field is to be dry ploughed for 2 times three weeks before
planting time.
Later field may be ploughed with 5 – 10 cms of standing water and
for 2-3 times and this process is known as puddling.
Dry ploughing may be carried over with tractor or power tiller.
If country plough is used, the ploughing has to be resorted for more
number of times. This preparatory ploughing facilitates the formation
of an impermeable layer at 15 cms depth of the soil which prevent percolation
of water to the deeper layers.
It also helps in removal of weeds and incorporation of green manure’s
if applied.
The application of 10 tons of farm yard manure or green manure and
its incorporation by puddling is recommended. This operation facilitates
better decomposition of the manure and/or the green manures.
The fertilizers recommended for basal application has to be applied
before the last puddling and incorporated.
Later proper levelling has to be made before
transplanting the seedlings.
Some times irrigation water is received late in the season due to
delay of monsoon rains or in sufficient rain fall, in such occasion
the field has to be ploughed cross wise with the receipt of first monsoon
rains.
Later the field has to be flooded and puddled twice at least 3 days
before transplanting with the application of recommended basal dose
of fertilizer in the last puddle and incorporated.
Transplanting
Manual
The puddled land has to be levelled uniformly before transplanting.
Levelling can be done by using an implement known as Wooden plank.
In case of heavy soils planting has to be resorted one or two days
after levelling when the puddled soil is settled.
In case of light and sandy soils planting has to be done immediately
after levelling.
During planting a thin film of water (2 cm) has to be maintained in
the mainfield.
Transplanting of 20-25 days old seedlings (4-5 leaf stage) at 2-3
seedlings/hill is recommended.
It has been observed that the delay in transplanting of seedlings
by one day beyond 30 days of nursery age, reduces 50-100 kg/ha in grain
yield.
Planting at shallow depth of 3-4 cm is advisable, as shallow planting
facilitates quick establishment of seedlings, more tillering and subsequently
better crop growth and yield.
In the planted areas the following spacing is recommended for planting.
Season
Variety
Spacing
1st crop
Medium duration, Short duration
20
cm x 15 cm 15 cm x 10 cm
2nd crop
Medium duration, Short duration
20 cm x 10 cm 15 cm x 10 cm
3rd crop
Medium duration, Short duration
20 cm x 10 cm 15 cm x 10 cm
In random planting areas, sufficient care is necessary
to maintain 33 hill/m2 in kharif crop and 44 hills/m2
in Rabi crop.
When over aged seedlings are used 5-6 seedlings
may be planted per hill and ensure 25 % extra plant population
by planting at a closer spacing
Clipping the leaf tips prior to planting
is recommended to eliminate rice stem borer egg masses if any
to the main field.
Planting by leaving alleys (pathways) of 20cms width for every 2mts
in sun-rise and sun-set direction helps in better transmission of sunlight,
better air movement in rice field, minimize the activity of insect pests
like BPH and thus a higher grain yield can be obtained.
Alleys also facilitates free movement in
the field for undertaking operations like weeding, fertilizer application
and spraying of pesticides etc,.
25 labours are required to plant one hectare of paddy field in a day
of 6 hours.
Early planting in the beginning of July for kharif, and beginning
of December for Rabi gives better yields.
Gap filling may be done twice at 10 days and 15 days after planting
if required.
Mechanical Planting
Manual transplanting is a labour-intensive operation
comprising nursery raising, uprooting of the seedlings, transporting
and transplanting the uprooted seedlings in the main field, with a total
labour requirement of about 280-350 man-hrs/ha
High labour demand during the peak periods adversely
affects the timeliness of operation, thereby reducing the crop yield.
The steady drift of agricultural labor to industrial
sector is adding more to the woes of the rice farmer.
Because of drudgery and notion that the farm operations
are below the dignity.
Labour availability, in general, has decreased
considerably in farm operations.
To offset these problems, mechanical transplanting is
the solution.
Many transplanters were developed in the past involving
the use of traditionally grown paddy nursery for mechanical transplanting.
However, several on-farm attempts made with different
models of transplanters using the traditional root washed nursery were
not successful because of the machine-related problems to use the nursery.
This called for the necessity of raising the nursery
in a special way, called mat nursery technique.
Among the existing commercially available designs
suiting mat nursery, Chinese model of paddy transplanter is found to
have great promise.
Transplanter Operation
For efficient operation of transplanter the land
preparation and knowledge of the mechanical provisions incorporated
with the transplanter are essential to be known.
Land Preparation
Puddle the land, level it and remove the water after 24 hours (for
clayey) or 12 hours (for sandy/loamy soil) before the transplanting.
In black or clayey soils the settlement is critical as the loosened
soil can burry the seedlings planted.
Just before the operation of transplanter, a thin film of water is
necessary to ensure the free movement of transplanter and avoid adhering
of soil to the moving parts of the transplanter.
Performance
There will be a net saving of 40 per cent over
the manual transplanting.
It can transplant about one hectare in a day of 8 hour
run.
The transplanter performs with missing hills of 2-3 per
cent.
The machine cost is about Rs. 1,05,000 and is marketed
by VST Agro Inputs, Mahadevpura, Whitefield Road, Banglore – 560 048.
Maintenance: Check and tighten bolts, grease high friction parts about
every 8 hours of operation.
Operation speed: For tractors, operate at around ¾ full throttle.
Many operations can be performed around 7-8 Km/hr. If rpm drop by more
than 200 upon engagement of equipment, then use a lower gear.
Primary Tillage
Ploughs (Mould board, Disc,Tine,Offset)
Objectives
To obtain required tilth of 10-15 cm. depth.
To open soil for drying
To uproot stubbles and weeds
To burry trash under soil
To kill weeds
Disc Plough
Key points
Power requirements are in the order of 14-26 k W/m at 7.2 km/hr
Stabilizer chains should be relatively loose (but not so loose that
implement hits tires)
Plough should be level in two planes (front to back, side to side)
If the tractor is "Pulling" to one side, then the plough
is not properly adjusted.
Depth of cut should be uniform – results if plough is level.
Field should be as level as possible after ploughing (no ridges)
Mould board plough
The initial opening of wet soils can be done with
minimum water in the field with a mould board plough fitted with
disc or a plough.
The disc coulter helps to minimise the clogging
of the mould board plough with weeds, stubble and the soil.
It takes nearly five days to complete the initial ploughing
operation of one hectare.
Water is to be let in after the initial opening and
left for a period of about one week for decomposition of the weeds and
for complete soaking of the soil lumps.
Secondary Tillage
Disc Harrow & Offset Disc
Rotavator
Puddler
Land plane
Disc harrow and Offset disc
The secondary tillage, consists of two operations
and disc harrow completes the puddling of one ha in 12 to 15 hours.
In well soaked soil disc harrow can be used for puddling without initial
opening and in such case 4 to 5 operations are generally required.
Disc harrow for puddling should be provided with scrapers for keeping
the disc clean from mud and weeds.
A light type of tandem disc harrow (weight 40 kg) with 8 discs spaced
at 13 cm each having a working width of 110cm in two gangs is very much
suitable for puddling operation.
The draft (97-122 kgs) of such a disc - harrow was less than that
of wooden plough (136-160 kgs).
The yield of paddy crop from the field puddled by disc harrow was
the highest in the field experiments, conducted on use of different
type of bullocks – drawn implements.
Tandem disk
Two sets of gangs front and rear in the shape of an "X".
Front disks face out ward (and throw soil outward) – back disks face
inward.
Offset disk
Single front gang with single rear gang. Concave face
of gang disks face opposite directions.
Objectives Under wet (saturated) conditions
To work soil 10-15 cm (4-6") deep.
To tear up roots.
To soften ground for subsequent puddler operation.
To chopping , incorporation of straw & to kill weeds.
Key points
Power requirements are in the order of 14-18k W/m at 7.2 km/hr
Stabilizer chains should be relatively loose (but not so loose that
implement hits tires)
Level in two planes (front to back, side to side)
Main adjustment is top hitch
As the angle of a harrow is increased, the depth of cut also increase.
Front angle of disks is generally about 20 degree, and the back disks
slightly more.
Front disk blades wear faster than following blades
Have bumper pads between center disks (to stop disks from knocking)
Cut to a maximum of ¼ of the disk diameter
Should leave a relatively flat surface – a depression or ridge in
the middle of a tandem disk harrow indicated that disk spacing, working
speed or top link of the three point hitch need adjustment
Don’ts
Disk cut should not overlap (i.e., back disks cut should be between
front disk cut)
Don’t cut deeper than ¼ of disk diameter
Rotavator
Objectives
Develop suitable tilth for seed germination/planting
Kill weeds
Uproots straw.
If possible use of Rotavators should be limited, because:
Energy requirements are more than other land preparation
equipment.
Involve a lot of moving parts so maintenance costs are
higher. Often used for nursery seedbed.
Key Points
Power requirements are in the order of 20-35k W/m at 7.2 km/hr
PTO shaft turns at 540rpm
PTO shaft should overlap by 10-15 cm.
PTO shaft should be horizontal to the ground when the rotovator is
lowered and in use.
Blade depth - the maximum cut should be
approximately 1/3 of diameter
Don’t:
In dry fields, you should NOT turn in the field with
rotavator down .
Puddler
Objectives:
Decrease weeds
Decrease percolation as a result of soil dispersion.
Level the soil for better planting conditions and/or for snail control
(where a problem)
Key Points
Power requirements are in the order of 7k W/n at 7.2 km/hr
Puddlers should be used only when necessary for snail and water management.
Note: Rotopuddlers (e.g., those used at IRRI) can be used
with a "Laser" guided System.
Comb Harrow
The comb harrow commonly used in the
Philippines and recently introduced in India, is simple efficient one
for puddling of wet field, after initial opening has been made by the
plough.
The tines of harrow penetrate about 15 cm deep in the wet ploughed
soil and effect puddling by stirring and combing action.
The weed stubbles and mud accumulated in front of the harrow are easily
removed by tilting the handle forward and allowing the accumulated material
to escape below the tines in course of operation.
The draft of the implement varies from 114 kg to 112kg which is with
in the pulling power of a pair of average sized bullocks.
Two or three operations of the harrow are adequate to complete the
puddling of wet soil after one initial ploughings by mould board plough.
Bullock drawn puddler
Puddler is used for preparation of paddy fields with standing water
after initial ploughing.
It breaks up the clods and churns the soil.
The main purpose of puddling is to reduce percolation of water, to
kill weeds by decomposing and to facilitate the transplanting of paddy
seedlings by making the soil softer.
Puddling is done in a standing water of 5 to 10 cm depth.
A common puddler used in this country has three puddling units, each
having 4 paddles mounted on an axle.
The axle with the puddling units is freely mounted on two bearings,
fitted on a frame, made of metal or wood.
The weight of the puddler including its beam is with in a range of
30 to 40 kg only.
The puddler consists of
Frame
Paddles
Metal cross
Axle
Beam
Handle.
Frame: The frame consists of front piece, the rare and side pieces
made of steel angle section or wood.
Paddles: Paddles are made of mild steel sheets having a thickness
of about 3.15mm. The size of the paddle is about 225 x 125 mm . The
paddles are riveted to metal cross.
Metal cross: Metal cross holds the paddles in position. It’s made
of mild steel flat.
Axle: Axle is made of mild steel bar of about 25 mm in diameter or
of mild steel pipe.
Beam: Beam is made of wood and is suitably fixed to the frame with
the help of braces and the other end to the yoke for hitching to animals.
Handle: Wooden handle is attached as handle supports for guiding the
movement of the puddler.
Power tiller with a Rotavator
A 10 H.P power tiller with rotavator is very efficient in puddling
of wet lands. Because of the wide difference between the linear speed
of the tiller and the rotary speed of the rotavator, it is possible
to get land throughly puddled to an observed depth .
Puddling and levelling or trampling of green manure crop can be done
in one operation by other tiller keeping the rotavator on high speed
(505) Rpm and tiller on low speed (24 to 39m/min).
Tractor with cage wheels
A tractor with cage wheels and paddy disc harrow was
studied for puddling operation. A minimum of three operations are required
for a satisfactory puddle for transplanting.
It takes nearly seven to eight hours to prepare one hectare
of land at an approximate cost varying from Rs.80 to 100, which is more
or less comparable to the use of wooden plough in regard to cost.
The 35 HP MF tractor with a rotavator when used for puddling
soil with 5 to 10 cm depth of standing water on the surface, required
less man hours and has higher turn over as compared with disc harrow.
The depth of puddle and distribution of soil aggregate
obtained with rotavator are not in any way inferior to that obtained
with paddy-disc harrow.
It has been also observed that practically little
levelling is required after the puddling operation.
The land levelling is carried out with the following equipment.
Land Plane
Objectives
Smoothen the land surface(not level)
Key points
A land plane will typically require 28 KW/m.
Should run at about ½ full (in practice, it may run empty 10-15% of
the time)
The soil aggregate size should be less than the height of the cut
The cut will often be about 1 inch.
Other land levelling equipment
A ladder or a wooden beam is used for levelling, the
leveller consists of a single plank held at an inclination to horizontal
surface between two hinged side plates curved upward.
The inclined edge is provided with an angle iron while
working in dry condition the weight of the implement and operation is
confined to the sharp edge and thus make it more effective in breaking
the clods as compared to ladder type where the weight is distributed
over the entire surface area of the two plants.
Under wet conditions the side plants permit accumulation
of water in front of the leveller making it float on the water and there
by reducing its weight and the draft by 40% due to buoyancy, the implement
of 2.5 m width has a comparable (even less in case of working under
wet condition) draft to that of a 2 m ladder type leveller.
Mechanical paddy transplanter
Features of the machine
Available with its own source of power of 3-HP diesel engine.
Covers eight rows at a time with a row to row spacing of 23 cm.
Provision to vary the plant to plant spacing – 10 and 12 cm.
Provision for cage wheel for field use and rubber wheel for transport.
Operation of the transplanter
Check oil level in gear box, fuel tank and grease the specified parts.
While operating observe for any missing hills in any particular row
and diagnose the problem immediately.
The missing hills can be due to presence of stones/foreign matter
that would have obstructed the fingers that pick the seedlings from
the tray.
Choose the right speed of operation for a plant hill to hill distance
of 10 or 12 cm.
Observe the number of plants per hill and adjust to the requirement
using the lever operating the finger movement.
Observe the depth of planting and adjust the lever accordingly.
For efficient operation of transplanter the land preparation and knowledge
of the mechanical provisions incorporated with the transplanter are
essential to be known.
Land preparation
Puddle the land, level it and remove the
water after 24 hours (for clayey) or 12 hours (for sandy/loamy soil)
before the transplanting.
In black or clayey soils the settlement is critical as the loosened
soil can bury the seedlings planted.
Just before the operation of transplanter, a thin film of water is
necessary to ensure the free movement of transplanter and avoid adhering
of soil to the moving parts of the transplanter.
Performance
There will be a net saving of 40 per cent
over the manual transplanting.
It can transplant about one hectare in a day of 8 hour
run.
The transplanter performs with missing hills of
2-3 per cent.
Available Transplanters
Now a days mechanical transplanting of paddy is also
recommended and practiced in some places.
M/s Godavari farm equipment’s, Jagityala, Kharimnagar
district developed a machine with modification of the original machine
fabricated by international rice research institute.
There are two types in this machine namely
V.G.T-6 and
V.G.T-8
which are manually operated.
With V.G.T-6 machine 6 rows could be planted at a time
with spacing of 20 cm while V.G.T-8 type 8 rows could be planted at
a time with spacing of 15 cms.
With V.G.T-6 eight cents of area could be planted per
hour while with V.G.T-8 ten cents could be planted/hr
M/s Escort & co. had developed a power operated machine
for transplanting paddy seedlings.
For using this machine nursery has to be raised in plastic trays using
16 kg of seed in 80 plastic trays to cover an acre.
With this machine one acre could be planted
in about 90 minutes.
Though machines are available for transplanting, most of the rice
growers are resorted to manual transplanting as on-to-day
Land Preparation
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