B.N.- Brassica oleracea .L. var. botrytis Family: Cruciferrae
Nutritive Value- The Cole crops are rich source of vitamin C and A.
Particular Cauliflower Cabbage Broccoli
Carbohydrates (g) 4.0 4.6 5.5
Protein (g) 2.6 1.8 3.3
Fat (g) 0.4 0.1 0.2
Vitamin A (IU) 51 2000 9000
Vitamin C (mg) 56 124 137
Calcium(mg) 33 39 1.29
Variety-
Early- Silver cup 60, White glass, Rami, Milkway, white flash, Sweta
Late- Kathmandu local, Dolpa snowball, Kiojaint, Sarlahi Deepali, Jyapu, N.S. 90, Snowdome, N.S. 84 etc.
Climatic requirement and soil- Indian varieties of cauliflower can tolerate to high temperature while snowball group is very sensitive to high temperature. Curd formation in cauliflower is sensitive to high as well as low temperature. Different varieties of cauliflower require very specific temperature for their curd formation and its quality. Indian varieties of cauliflower can tolerate the temperature as high as 40oC. The optimum temperature for most of the cole crops for seed germination and growth is 12-18oC except early cauliflower. High temperature in cauliflower caused riceyness, fuzziness, buttoning, yellowing and loosening of curds. The low temperature injury in cauliflower causes blindness.
Fertile, medium to heavy well drained loam soils are best suited to grow cole crops. Cole crops can be grown in slightly acidic to saline soils. However, the optimum pH range is 6.0-7.0 because there is incidence of club rot disease. Molybdenum deficiency occurs more frequently in acidic soil below pH 5.5 which causes whiptail disorder in cauliflower. Therefore, liming of soil should be done to raise the soil pH above 5.5. One deep ploughing and 2-3 light ploughing followed by planking is essential to obtain the fine tilth.
Nursery raising- The sandy loam and loam soils rich in organic matter are suitable for the nursery. In soil with good tilth 15 cm raised nursery beds of 3m length and 1 m width are prepared. About 20-30 beds are sufficient for on hectare area. 15 kg FYM and 50g of N:P:K (19:19:19) complex fertilizer, 200g powered neem cake along with 10g carbofuran per bed is incorporated. The beds are drenched with captan or any systemic fungicide @ 2-3 g/liter of water. Seeds are sown thinly in rows 6 cm apart and 1 cm deep. The beds are covered thinly with straw or grass layer and irrigate with rose-cane. On germination (8-10 days) the beds are again drenched. After the appearance of first true leaf seedlings are thinned out. On the 20th day Monocrotophos or any systemic insecticide (1.5-2 ml) and on 25th day mancozeb are sprayed. During the last week of nursery, the seedlings may be hardened by slightly withholding water for better establishment of seedlings. The seedlings with 5-6 true leaves are transplanted after 30 days.
Seed Rate- For Early crops 600 to 750g of seed are required and for late crops 375 to 400 g seed are required per hectare.
Sowing time- The seed is sown in raised nursery beds which should be sterilized by formaldehyde or some fungicidal treatment. The seed for early sowing should be treated with some mercurial fungicide to save the young seedlings for damping off. According to season early sowing is done from the middle of Jestha to the end of Asar. The late crop is sown from the middle of Bhadra to the end of Ashwin. According to altitude the Magh to Baisakh is suitable time for high hills while shrawan to falgun for mid hills and asar to shrawan in terai depending upon varieties.
Transplanting- The seedlings are transplanted when four to six weeks old, depending upon the season in a well prepared field. The planting distance depends upon the fertility of soil, season, variety and market demand. In some markets small to medium sized curds are preferred to large- sized ones. Closer spacing is given for supplying cauliflowers to such markets. Generally, a spacing of 45cm away is kept for the early varieties and 45 cm from plant to plant and 60 cm from roe to row for late varieties.
Manures and fertilizers-The cauliflower requires very heavy manuring as it removes large quantities of major nutrients from the soil. The fertilizer practices differ in different regions. For best results, 20 to 30 tons of farm yard manure or compost should be applied per hectare three to four weeks before transplanting. 200 kg of nitrogen, about 120 kg of phosphate and 200 kg of potash per hectare should be applied before transplanting. A placement of 5 to 7 cm deep on both sides of rows are advisable. A cauliflower crop often shows boron and molybdenum deficiency symptoms when grown either on an alkaline or highly acidic soil. In such cases 10 to 15 kg of borax per hectare may be applied to the soil or two sprays with 0.3 percent borax on the seedlings may correct the boron deficiency symptoms. Molybdenum deficiency symptoms occur in highly acidic soils and can be corrected by liming or application of about 1 to 1.5 kg per hectare of sodium molybdate.
Interculture and Irrigation- Frequent shallow cultivation should be given to the soil to kill weeds and provide soil mulch. Cauliflower being a shallow-rooted crop, most of its roots is within 45 to 60 cm of the top soil.
Deep cultivation should, therefore, be avoided. The plants should be earthed up about 4 to 5 weeks after transplanting. Water must be supplied to ensure continuous growth. An early crop after transplanting may need irrigation twice a week and late crop once a week.
Blanching-A perfect head of cauliflower pure white, it is necessary to execute sunlight to obtain this. White head is protected by the inner leaves but later the curds are exposed. The common practice is to bring the outer leaves up over the head and tie them with a twine or rubber band,it is easy at the time of harvest to select those tied earliest.
Harvesting, Grading, Packing and Storing-Cauliflower is harvested when the curds attain a proper size and before they begin to discolour. It is separated into three grades, depending upon the size colour, quality and variety. The usual method of packing and transport of cauliflower is in big nets and trucks. Tight packing is essential to prevent shifting and bruising. In some countries cauliflower is packed in crates and wire-bound boxes. Cellophane and transparent films are also used to pack cauliflowers which are hydro-cooled to remove field heat. Cauliflower with leaves attached can be stored for 30 days at 00C with 85 to 90 percent relative humidity.
Yield- The yield of cauliflower may vary from 15 to 20 tons per hectare. The early crops give low yields and the mid-season crops give high yields.
Physiological Disorders
Browning (Brown rot or red rot): This is caused by boron deficiency. The trouble first appears as water-soaked areas in the stems and on the surface of the curd. Later, these areas change into a rusty-brown colour. Browning is associated with hollow stems. Other symptoms are changes in colour of foliage, thickening, brittleness and downward curling of order leaves. Application of borax @ of 10 to 15 kg per hectare on acid soils controls browning, though the amount depends upon the character of soil, soil reaction and the extent of deficiency. On neutral and alkaline soils, a larger quantity should be used.
Whiptail: The results from the deficiency of molybdenum becomes unavailable in very acid soils. Liming may correct the deficiency symptoms in such cases. There is varietal sensitiveness to molybdenum. The leaf-blades do not develop properly. In the severe cases only the midrib develops, and whiptail can be prevented by bringing the soil pH to 6.5 by liming or by applying 1 kg of sodium or ammonium molybdate per hectare.
Buttoning: The term buttoning is applied to the development of small heads or buttons. The plants do not develop normally and the leaves remain small and do not cover the developing heads. Deficiency of nitrogen is the main cause of buttoning. Planting early varieties as late season may also cause buttoning. Apply recommended dose of N.
Blindness: Blind cauliflower plants are those without terminal buds. The leaves which develop, large, thick, leathery and dark green. Blindness is supposed to be due to low temperature when the plants are small or due to damage to the terminal bud during handling of the plant or injury by insects pests. Protect crop from the low temperature and control the insect-pest.
Riceyness- Pedicles bearing the individual flower elongated. The curd become granual and loose. Warm weather and poor quality seed is responsible for this disorder. To mange this disorder, sow the seed when temperature is favourable.
Fuzziness- Peduncle elongated to give a rise a full velvety appearance of curds formed. This is mainly caused due to unfavourable climatic condition. To control this disorder avoid sowing when temperature is high.
Hallow stem-This disorder affects all cole crops. Hollowness caused by boron deficiency is characterized by the appearance of water soaked areas and discolouration of tissues. When it is caused due to excess of N, The affected stem remain clear white with no sign of disintegration. To control this, spray borax @ 0.3-0.4%, reduce the dose of N and transplant the crop at closer spacing.
Diseases-
Soft rot: It occurs in the field usually after an attack of black rot, or after mechanical injury of nearly mature curds. The casual organism os another bacterium known as Erwinia carotovora.
Clubroot: The roots show large swellings presenting a clubbed appearance. It is caused by a fungus Plasmodiophora brassicae. The foliage wilts on sunny days and recovers towards the evening. The disease is prevalent in acid soils. Avoiding cole crops in affected plots, long rotations without any cruciferous crops and keeping the soil alkaline are the control measures.
Black leg (Phoma lingam): It affects all the parts of the plant. Infection often occurs on the stem of the young plants in the seed- bed or in the field, causing dark sunken areas. The wilting of the plants is characteristic of the advanced stages of this disease. Hot water treatment @ 50 oC for 25-30 minutes, is affective in destroying the fungus in the seed.
Downy Mildew: It is common in young plants and is characterized by the appearance of purplish- brown spots on the underside of the leaves. Downy growth usually appears on the under surface of the lesions. The upper surface of the leaf on the lesion is tan to yellow. The casual organism is Peronospora parasitica, an obligate parasite. The primary inoculums being present in the soil, sanitation, and crop rotation help in reducing the infection. The disease also affects cabbage.
Insect pests
Cabbage maggot: The maggots first attack the young rootlets and then burrow into the main root, causing the plant to wilt. Dusting or application as a water suspension of Calomel or application of Dieldrin also controls the insects.
Green cabbage worm and cabbage looper : These feed on the foliage of cauliflower and can be controlled by spraying DDT or malathion 2 to 3 weeks prior to harvest and application of Pyrethrum when the curds have formed.
Cabbage and Turnip Aphids: These insects are more injurious during the latter part for the growth or when the crop is left for seed production. The attack is controlled by spray of malathion or parathion but if the curd is ready for harvest, nicotine sulphate is usedwww.narc.gov.np
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