These recommendations are made for the medium altitude areas
(upto 1500 m) particularly in Wangdue-Punakha valley and Trashigang-Monggar.
FIRST CROP
VARIETIES
No. 11
• Cold tolerant, high yielding, early maturing, Japonica
rice.
• It has good seedling cold tolerance, however symptoms
like yellowing of leaves and stunting may occur under very
low temperature.
• It is about 90 cm in height and matures in 160 days
from sowing.
• It has yield potential of over 3 t/acre under good
management but it is difficult to thresh.
Barket
• Cold tolerant, high yielding, early maturing, japonica
rice.
• It has good seedling cold tolerance and produces vigorous
seedlings under polytunnel nursery.
• It is 90-95 cm in height and matures in about 155
days.
• It is very easy to thresh unlike No.11.
• It has a yield potential of over 2.5 t/acre under
good management.
CROP ESTABLISHMENT
• First crop can be established either by transplanting
or direct seeding.
Transplanting
• First week of Feb. is the recommended time to sow
nursery.
• Use a seed rate of 25-30 kg/acre.
• Raise seedlings using a polytunnel nursery bed.
• Raising of seedlings in polytunnel nursery (see leaflet
on rice seedling production)
Time of transplanting
• The ideal transplanting time is the second week of
March.
• The method of transplanting, either in line or at
random, should be decided depending upon the weed control
method to be adopted and labour availability.
Direct Seeding
Direct seeding greatly reduces labour cost in establishing
a crop of rice. A direct seeded crop of rice also matures
about a week earlier than transplanted. However, the general
requirements for successful direct seeding are good rice variety,
good land preparation, good weed control, and good water supply
and management. Direct seeding can be done in 2 ways:
Dry Furrow Seeding
• Land preparation should be done in dry soil to get
a well pulverized seed bed as in a dry bed nursery.
• Open up furrows 2-3 cm deep and 20-30 cm apart
• Drop unsoaked seeds evenly or place 4-8 seeds at a
distance of 10-15 cm along the furrow.
• After sowing cover the seeds lightly with fine soil.
• Irrigate the field lightly after sowing. Do not keep
standing water in the field as excess water deprives the seeds
of oxygen and they eventually die. Keep the field moist until
the seeds germinate.
• Keep the field saturated till seedlings attain a height
of about 10 cm. Increase the water level gradually.
• Use a seed rate of 40-50 kg/acre.
• Optimum sowing time is the first half (1-15) of March.
Wet Broadcast Seeding
• Prepare the land as for any transplanted rice crop.
However, field should be properly levelled for efficient drainage.
• After final land preparation, allow the mud to settle
overnight to avoid sinking of seed. Keep water level to the
minimum.
• Broadcast pre-germinated seeds (soaked for 24 hours
and incubated for 36-48 hours) evenly. Walk backwards while
seeding and avoid making too many mud depressions that collect
water and rot the seed.
• Keep the water level as minimum as possible till the
seeds secure roots and emerge (2-5 days but may take longer
if temperature is low). Then, increase the water level gradually
as seedlings grow in height.
• Use a seeding rate of 70-90 kg/ha.
• First half of March is the optimum seeding time.
• Weed control is the biggest challenge of this method.
Butachlor is not suitable as it suppresses emergence and arrests
seedling growth at early stages. However, Sanbird and NC 311
can be successfully applied 5-7 days after seeding without
affecting rice growth.
Other activities like field preparation, manures and fertilizers,
weed control etc are similar to a normal crop of rice.
SECOND CROP
VARIETY
IR 20913
• It is an advanced selection from the cross between
Bhutanese white rice and an IRRI line.
• It is about 100 cm tall and mature in about 130-140
days from sowing.
• It has an yield potential of over 3 t/acre under average
to good management conditions.
• It has moderate cold tolerance at seedling and flowering
stages and is also good for late planting of the normal season
crop.
CROP ESTABLISHMENT
Nursery sowing : June 15 - June 30
Seed rate : 20-25 kg/acre
Nursery raising : Seed selection as for the first crop. Seedlings
could be raised either by wetbed or semi-drybed methods.
TRANSPLANTING
Time of transplanting : July 15 - July 30
Transplant 20-30 days old seedlings using 2-3 seedling/hill.
Maintain closer spacing as recommended for the first crop.
Other practices are similar as for a normal rice crop.
For further information contact
Mahesh Ghimiray, Field Crops Sector, RNR-RC, Bajo
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