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About 80% of the wheat area in Bhutan is wheat grown after
rice. All varieties grown in the rice-wheat system are introduced
spring wheats grown during winter.
VARIETIES
Sonalika
• Early maturing variety with wide adaptation.
• 80-85 cm tall and matures in 135-145 days at medium
altitudes.
• Yields 2 t/ha under moderate management. However,
it is responsive to fertilizers particularly nitrogen, and
yields over 3 t/ha can be obtained.
• Highly susceptible to yellow and brown rusts.
Bajoka-1 (HD 2380)
• Recommended for medium and low altitudes.
• Matures 155-160 days after sowing.
• Grows to a height of 80-85 cm.
• Attractive bold amber grains.
• Yields 2.5-3.0 t/ha under moderate management.
• Highly responsive to inorganic fertilizer.
• Moderately resistant to yellow (stripe) and brown
(leaf) rusts.
Bajoka-2 (BL 1093)
• For medium and low altitude areas.
• Matures 150-160 days after sowing.
• It is more than 100 cm tall.
• Attractive bold whitish grains.
• Yields 2.5-3.0 t/ha under moderate management.
• It can highly resist yellow (stripe) and brown (leaf)
rusts.
FIELD PREPARATION
Where bullocks are the source of power, one deep ploughing
followed by a second ploughing or harrowing using a local
plough.
Where tractor/power tiller is available, one deep ploughing
followed by 2-3 harrowings is required. Planking should be
given to prepare a well pulverized seed bed.
Irrigate 7-10 days before sowing to ensure good germination.
SEED AND SOWING
Selection of seeds: Use healthy seeds of a recommended variety.
Treat the seeds with Vitavax at the rate of 2.5 g/kg seed
to control loose smut.
Seed rate: 100-130 kg/ha.
Sowing time: November. An early sown crop is more likely
to escape rust infection, and early sowing also ensures enough
residual soil moisture for germination.
Method of sowing: After the final land preparation and application
of manure and fertilizer, the seeds should be uniformly broadcast
and then covered by harrowing.
MANURE AND FERTILIZERS
Apply 5 t/ha of well-decayed FYM at the time of land preparation
and work well into the soil.
For higher yields supplement the manure with chemical fertilizers
at the rate of 50:30:20 NPK kg/ha. Half the nitrogen and all
the phosphorus and potassium should be applied basally. The
remaining nitrogen should be topdressed at first irrigation.
IRRIGATION
The crown root initiation (CRI) stage and heading stage are
critical stages when the wheat plant suffers most from moisture
stress. If the water supply is limited the following schedule
of irrigation should be adopted.
First irrigation: At CRI, 25-30 days after sowing.
Second irrigation: At booting stage, 70-75 days after sowing.
Third irrigation: At milk stage, 90-100 days after sowing.
DRAINAGE
Wheat irrigation is complicated by the formation of a plough
pan during puddling for rice. Waterlogging occurs after irrigation
because of the slow vertical movement of water. Wheat is particularly
sensitive to waterlogging at the early seedling stage. If
severe waterlogging is observed, drain the excess water by
constructing small channels across the field.
PLANT PROTECTION
Yellow/stripe rust
• Use resistant varieties
• Avoid late sowing
• Do not use excess nitrogenous fertilizers.
• Spraying 0.2% Dithane-45 may minimise rust development.
Loose smut
• Use clean, disease-free and healthy seeds.
• Treat seeds with Vitavax at a rate of 2.5 g/kg seed
before sowing.
HARVESTING AND THRESHING
Harvest when the leaves and stems turn yellow and become
fairly dry. Timely harvest ensures optimum grain quality and
consumer acceptance.
Harvesting is done manually using serrate edged sickles.
After harvesting, dry the crop for 3-4 days, then stack and
thresh. Threshing can be done either manually or using a power
thresher.
For safe storage, cleaned the grain and dry well for a few
days to reduce moisture content to 10-12%. Occasional sun
drying should be done to avoid losses during storage.
For further information contact
Mahesh Ghimiray, Field Crops Sector, RNR-RC, Bajo
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