The document discusses knol khol (kohlrabi), a vegetable from the Brassica family, detailing its origin, morphology, climatic and soil requirements, varieties, land preparation, nursery management, transplanting, aftercare, pest and disease control, harvesting, and storage. It highlights the vegetable's edibility, health benefits, and suitable agricultural practices for optimal growth. Knol khol is noted for its high vitamin content and potential cancer-fighting properties.

1. KNOL KHOL
PRESENTED BY :- N.U.M.PERERA
UWU/EAG/11/0041
V.P.A.DILRUKSHI
UWU/EAG/11/0040
(Brassica caulorapa)

2. INTRODUCTION
 Family:- Cruciferaceae
 Origin: Northern Europe
 Also known as Kohlrabi, Kohlrabi greens, Navalkol, Gunth
Gobhi, Ganth gobhi
 The Whole plant is edible however, it is mostly used for its
bulged swollen stem
 It is excellent vegetable if used at its early stage before it
becomes tough and fibrous
 Major growing areas : up country of SL

3. MORPHOLOGY
• formation of knob (tuber) which arises from a thickening of the
stem tissue above the cotyledons
• The fleshy edible proration is an enlargement of the stem, which
develops entirely above ground and is used as a vegetable
• The edible portion is globular to a slightly flattened stem

4. Climatic Requirement
 cool season crop
Temperature
 It can withstand extreme cold and frost better
than other cool season crop
 Germination - 15 0C to 300C
 Tuber production- 100C to 200C
 The low temperature - develops anthocyanin
pigments on knobs or plant parts
 Continuous hot weather is detrimental which
induce knob development

5.  soil
 successfully grown on all types of soil
 But the sandy loam and clay loam soils are best
suitable
 pH 5.5-6.8
 A soil rich in manures and fertilizers produces
excellent knobs
 does not grow well in highly acidic soil

6. VARIETIES
• White Vienna
• Purple Vienna
• Grand Duke
• Gigante Purple Danube
• White Danube

7. WHITE VIENNA :
• variety this is an early variety with globular, light green, smooth,
tender, medium-sized knobs having creamy-white tender flesh
with delicate flavor
• plants are dwarf, leaves and stems are medium green
• yield potential of 150–200q/ha
• It matures 55–65 days after transplanting
• takes 50–60 days for knob formation

8. PURPLE VIENNA
• Medium size
• one week later than White Vienna
• Knobs are purplish-blue with greenish-white flesh
• It has purple leaves
• . It requires 55–65 days for knob formation with slightly better
yield potential than White Vienna

9. KING OF NORTH
• plant height of 20–30cm foliage is dark green, knob flattish-
round, leaf sheath large and well-spread over the knob
• It matures 60–65 days after transplanting
• . Early varieties mature 30–45 days after planting & characterized
by the horizontal position of the lower leaves
• The late varieties mature 70–100 days after planting

10. LAND PREPARATION
• The land should be well prepared and of good tilth for
sowing of Knol- Knol, 5- 6 ploughing should be given to
prepare a good tilth
• planking is essential to make soil pulverized and leveled
• The beds and channels are prepared to facilitate irrigation
• weeds and stubbles of previous crop should be removed
before the transplanting of this crop

11. NURSERY MANAGEMENT
• usually propagated by seed
• can also be propagated by cuttings such as tip cutting and
leaf cutting
• 60cm wide and 2.5m long nursery beds are prepared
• For minimizing the seedling damage, the nursery beds
should be treated with formalin (40% formaldehyde diluted
in 5–6 parts of water or captan )
• Then covering nursery beds for 2 days

12. • Soil is aerated well for at least 4 days before sowing
• Seeds are sown in rows at a distance of 5–6cm for ease in
manual hoeing, weeding and thinning
• A depth of 1.5–2cm is optimum since deeper sowing
delays the germination
• Time of Sowing:
Variety Time of sowing seed in
Nursery
Time of transplanting in
the main field
Early August September
Main September October
Late October November

13. • Then nursery bed is covered with grass to conserve
moisture for uniform germination
• Watering according to whether condition
• mulch is removed just before the seed germination to control
damping off

14. TRANSPLANTING
• 3 to 4 week old seedlings become ready for transplanting
• Ridges and furrow type beds used
• spacing 25cm × 25cm, 25cm × 30cm, 25cm × 40cm or
30cm × 45cm depending on climatic condition
• seedlings should be watered and protection may be given
from sun rays for 4 – 5 days

15. MANURING AND FERTILIZATION
• Knol-khol responds well to manuring, as it is a heavy feeder
• At the time of transplanting add N - 75 kg/ha , P - 50 kg/ ha
• second dose of 50 kg N should be given 1 ½ months after
transplanting

16. AFTER CARE
• Weeds are removed from field by hand weeding
• generally 2-3 weeding are done in the initial stage of growth
• the field must be kept free from weeds
• plant should be earthen up after 25 – 30 days of
transplantation

17. • The knobs may become elongated - in close spacing due to
lack of light as in knobs growing in the shade
• The production of elongated knobs may also be induced by
high temperature and excess of N

18. IRRIGATION
• Knol-khol requires a continuous supply of moisture for
uniform growth and development of knobs
• after transplanting, should be watered for 4 to 5 days(as
stated the seedlings, after transplanting, should be watered
for four to five days)
• should be given an interval of 6 to 7 days
• thereafter irrigation is done when needed, depending on soil
and weather conditions

19. PEST & DISEASES
Pests
• Aphids
• Thrips
• Mustard saw fly
• Semi looper
• Nematods
• Caterpillars & beetles

20. Thrips
Aphids
Mustard saw fly
Semi looper

21. DISEASES
• Damping off
• Leaf spot & blight
• Club root
• Black rot
• Root fly

22. PEST & DISEASES CONTROL
• Pruning of the old leaves
• Weed control & clean of field
• Use chemical & organic pesticides (foliar spray of garlic
extract at 3% concentration, Spray Trichoderma at 2-3 %
against root fly & black rot)

23. HARVESTING
• knobs are harvested by cutting the stem just below it by a
sharp knife or sickle before they are fully grown
• should be harvested when swollen stem reach a diameter of
5 to 7 cm and before it becomes tough and woody
• The plants are pulled out from the land
• generally marketed after removing both leaves and roots

24. Storage
• It can be stored in 3 – 4 days under ordinary conditions
• Cold storage can be stored for more number of days wrapped
knobs store well with better quality comparatively unwrapped
knobs

25. HEALTH BENEFITS OF KOHLRABI (KNOL-KHOL)
• rich in the antioxidant , so helps fight cancer
• contains high amounts of vitamins C, E and carotene
• considered good sources of dietary fiber
• contains sulphoraphanes and other isothiocyanates, which
are believed to stimulate the production of protective
enzymes in the body
• have antidiabetic activity