Cutworms
- Damages seedlings in the newly planted crop.
- Stems are chewed near the soil level during night.
- Some cutworms climb the host and feed on unopened buds.
- Many cutworms prefer wilted plant material and sever the plants sometime prior to feeding.
Control measures:
- Use of well-decomposed manure helps in reducing the incidence.
- Collection and destruction of larvae after flooding of fields/ beds.
- Soil drenching with chlorpyriphos (0.04%) or spraying of cypermethrin (0.0075%) on foliage and soil surface reduces the incidence.
- The colonies of the aphid are seen on leaves, bud and inflorescence.
- Damage is caused by nymphs and adults who suck cell sap from plant parts.
- Due to sucking of the sap curling of leaves takes place.
Control measures:
- During September/October when cole crops are transplanted, a month or so after transplanting a spray of malathion (0.05%) may be given.
- The activity of this pest remains low due to low temperature during winter, however, during February, when the temperature rises again a spray of the same insecticide may be given and it is repeated after 15 days if the attack persists.
Caterpillars
- Cabbage caterpillars and cabbage semi loopers cause serious damage to plants by devouring the foliage from mid-February onwards.
- Damage is caused by caterpillars of Pieris brassicae which feed in groups in the earlier stage and scrap the leaf surface but later on they eat up the entire leaves leaving only the harder mid rib.
- Besides, larvae of some other lepidopteran pests also cause damage.
Control measures:
- The yellow egg masses of the cabbage butterfly can be collected and killed by crushing.
- Spray of neem seed kernel extract (4%) and application of malathion (0.05%) also help in reducing the population of caterpillars.
Painted bug
- In seed crop, nymphs and adults suck sap from the foliage and pods thus resulting in shriveled seeds and poor yield.
Control measures:
- The pest can be controlled by spraying the crop with oxy-demeton methyl (0.025%) or dimethoate (0.03%) as and when the attack is noticed.
- Repeat spray if required.
- After spray observe 10-12 days waiting period.
Red ant
- The crop is attacked by red ants in many places.
- The insect feeds on the bark and root hairs of newly transplanted seedlings.
- The attacked plants dry up and die subsequently.
Control measures:
- Mix malathion dust (5 %) or follidol M dust (2 %) @ 20-25 kg per hectare in the basins of plants at the time of transplanting.
- In seed crop, rogue out undesirable heads before spray.
- During bloom, spray endosulfan (0.05%) in the evening to avoid poisoning to the pollinators and advise local pollinators to close down bee hives for the following day.
- Observe a waiting period of two weeks in the head crop.
Diamond back moth
- Damage is caused by the larvae which in earlier stage attack the leaves and later on feed on the exposed leaves making holes of variable size.
Control measures:
- Sprinkler irrigation after every third day in evening hours is effective.
- Spray application of endosulfan (0.05%) is also effective.
- Same insecticide should not be applied repeatedly.
Snails and slugs
- Damage the growing tips of plant and also the surface of curd in cauliflowers.
- They are problematic when crop is irrigated with sewerage water.
Control measures:
- Baiting with metaldehyde and bran (1: 25 in 12 L of water).
- Alum may be sprayed as a repellant @ 2% solution.
- Manifest in different types of disease syndromes.
- Some physiological disorders depend mainly on hereditary factor, whereas, other are fluctuation occurring in temperature, air, water, humidity, organic and inorganic nutrition.
Riceyness
- It manifests in the elongation of peduncle bearing flower buds rendering curds, granular, loose and somewhat velvety.
- A premature initiation of floral buds is characterised by riceyness in cauliflower and is considered to be of poor quality for marketing.
- Riceyness mainly develops during the warm weather.
- Hereditary factors have also been reported for riceyness.
- Heavy dose of nitrogen and high relative humidity also contributes to riceyness.
Control Measures:
- It can be controlled by cultivation of genetically pure seed and appropriate varieties with recommended cultural practices.
- Harvest while the curd is still firm, compact, white and fairly smooth; if it gets too mature, it will become grainy or ricey.
- Proper management of soil moisture and fertility during the development of head or curd.
Fuzziness
- It appears as the flower pedicels of velvety curds elongate.
- The anomaly is both hereditary and non-hereditary.
- Cultivation of cauliflowers, out of their normal season encourages fuzziness.
- Sowing good quality seed in right season under proper cultural practices minimizes fuzziness.
Leafiness
- This disorder is commonly seen by formation of small thin leaves from the curds which reduce quality of curd.
- Prevalence of high temperature during curding phase aggravates leafiness.
Control measures:
- It can be controlled by selection of varieties according to their adaptability and seasons.
Buttoning
- Development of small curds with inadequate foliage in cauliflower is known as buttoning.
- It is also referred to as premature heading.
- The leaves are so small that cannot cover the formed head.
Causes of buttoning
- Transplanting of more than 6weeks old (over aged) seedlings.
- Planting of early variety late and vice versa lead to buttoning.
- Hot and dry weather is unfavorable for vegetative growth of plants.
- When soil moisture becomes limiting factors, it checks the growth of the plants, which in turn, causes early formation of curds without maintaining their further enlargement.
- Transplanting of seedlings, obtained from poorly managed nursery bed.
- Slow plant growth in the nursery, overcrowding, and insufficient water, lack of weeding, bad condition of the soil, excessive salt concentration, low lying area or field with shallow and poor top soil may also cause buttoning.
Control measures:
- Nursery should be properly looked after to avoid any check in the plant growth.
- An adequate amount of nitrogen and water should be applied.
- Do not delay transplanting.
- Cultural practices should be carried out well in time and water logging and overcrowding should be avoided.
Blindness
- It means the plant without terminal buds or when the growing point collapse at an early stage and the terminal buds fail to develop and plant becomes blind.
- It occurs in over wintered plants and any cultural practice interfering in growth of the terminal bud may lead to blindness.
- It is characterised by the leaves that develops which are large, dark green, thick and lathery owing to the accumulation of carbohydrates.
Control measures:
- It can be controlled by avoiding young plants from low temperature exposures and avoid damage to seedlings from insect-pests/rodents.
Bracting
- The bracts are underneath the prefloral meristem, which corresponds to axillary buds.
- These bracts or leaves come out of the curd resulting in poor quality of curds for marketing as they turn green or purple in colour on receiving the direct sunlight at the surface of the curd.
- Temperature higher than the optimum during curding causes this disorder.
Control measures: Control of temperature during curding
Purple colouring
- Sometimes various pigmentations are occurred on the curd due to fluctuation in temperature.
Possible reasons:
- Fluctuation in temperature
Chlorosis
- In cauliflower, magnesium deficiency causes chlorosis when grown on highly acidic soils.
- Chlorosis shows on intervenial and yellow mottling of lower leaves.
- The affected leaves turn bronze in colour and become stiff.
Control measures:
- Use of fertilizers containing soluble magnesium keeps the disorder under control.
Premature seeding/bolting
- It means premature formation of seed stalks i.e. before the formation of heads or failure of leaves to form a solid head.
- The possible causes of bolting include early sowing of seeds, warm winter, extreme change in temperature, poor growth of seedlings and varietal characters.
Control measures:
- Use resistant cultivars, avoid planting/transplanting/setting plants too early into the field and prevent the stimulation of early plant growth.
Browning (Brown Rot or Red Rot)
- It is caused by boron deficiency which is influenced by soil pH.
- The availability of boron decreases at neutral soil reaction.
- It is characterized by sign on the young leaves that becomes dark green and brittle.
- Sometimes, the downward curling of older leaves followed by development of blister occurs when boron deficiency is severe.
- Curds may also show irregular water soaked spots, which later change to a rusty brown colour.
- In later stages, the stem become hollow with water soaked tissues surrounding the walls of the cavity.
- In more advanced stages, a pinkish or rusty brown area develops on the surface of the curd and hence is known as red or brown rot.
Control measures:
- This may be controlled by application of borax or sodium borate or sodium tetra borate at the rate of 20 kg/ha as soil application.
Whiptail
- Deficiency of molybdenum causes “whiptail syndrome” especially, in high acidic soils.
- The young cauliflower plants become chlorotic and may turn white, particularly along the leaf margins.
- The leaves also become cupped and wither and eventually the leaf dies and the growing point also collapses.
- In older plants, the lamina of the newly formed leaves is irregular in shape, frequently consisting of only a large bare midrib and hence the common name “Whip tail”.
Control measures:
- It can be corrected by application of lime or dolomite limestone to raise the soil pH up to 6.5.
- Apply 1.0 kg of sodium or ammonium molybdate per hectare.
Black Speck
- A physiological disorder in cauliflower common with the popular snowball cultivar.
- Black speck could be due to nutrient imbalance.
- Tip burn and internal browning in cabbage and Chinese cabbage is due to the inadequate transport of calcium to rapidly growing tissues.
Control measures:
- Foliar spray, with calcium nitrate may control the problem or alternatively by a reduction in nitrogen fertilizer
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