Carrot Physiological Disorders

Carrotb Physiological

DisordersToT to FFS Staff By Mr. Allah Dad

KhanProvincial

Coordinator IPM KPK MINFAL

Identification

Carrot (Daucus carota). The large taproots of this European herb are one of the most popular vegetables in North America. Like other biennial herbs, carrots store up food reserves in the main taproot during the first summer of growth, and then flower and die the following year. Carrots are typically harvested by the end of their first growing season. Wild flowering carrots are called Queen Anne's Lace, supposedly named after Queen Anne of England (1665-1714). Queen Anne apparently won an embroidery contest to see who could produce lace as beautiful as the intricate clusters of tiny white flowers of the wild carrot. Carrot roots are rich in the tetraterpene beta-carotene (C40H56), the precursor of the anti-oxidant vitamin A (C20H30O). During digestion, each beta-carotene molecule is broken down into two molecules of vitamin A. Vitamin A is also called retinol because it is almost identical to the retinol present in the rod cells of the retina of human eyes. Rod cells are sensitive to light and enable one to see at dusk and in dimly illuminated areas

Carrot

NitrogenDeficiency SymptomsThe Number and size of leaves were reduced and pale green colour of leaves change to yellow roots because thin, stiff and fibrous.

Correction MeasureFoliar spray of urea @1%

Symptoms

Growth dwarfed and thin; leaves pale green and older leaves yellow and red tints and die off early

Carrot Plants Nitrogen deficiency

Symptoms

Growth dwarfed and thin; older leaves strong purple tints and die off early

Carrot Plants Phosphorus deficiency

PotassiumDeficiency SymptomsLeaf colour change to pale yellow and brown scorches appear at laber stages. Violet streaks appear on roots. Growth in retarded.

Correction MeasureFoliar spray of KCl@1%

PhosphorusDeficiency SymptomsPlants were shorter, smaller leaves, distorted in shape and pink tinge appear along margin and veins. Formation of shortage root delayed.

Correction MeasureSoil application of recommended dose of Phosphorous fertilizer

CalciumDeficiency SymptomsSymptoms are marked on younger plant parts. Leaves become chlorotic fever and roots are smaller.

Correction MeasureFoliar spray of CaCl2@0.5-1.0%

Symptoms

Petioles collapse and leaves wither

Carrot Plants Calcium deficiency

Symptoms

Older leaves strongly chlorotic.

Carrot Plants Magnesium deficiency

MagnesiumDeficiency SymptomsChlorotic on nature leaves. Which later abscise and fall off. The roots are smaller in size, stiff and pale in colour.

Correction MeasureFoliar spray of MgSO4@0.5-1.0%

Symptoms

Growth squat and leaves curl backward; leaflets of older leaves develop marginal scorch, followed by general browning and collapse

Carrot Plants Potassium deficiency

Symptoms

Growth of young leaves restricted giving a rosette effect, older leaves orange tints; growing point may die.

BoronDeficiency SymptomsCrinkling of leaves; carrot size become smallerCorrection MeasureFoliar spray of borax@0.5%

Carrot Plants Boron deficiency

BoronDeficiency SymptomsCrinkling of leaves; carrot size become smaller

Correction MeasureFoliar spray of borax@0.5%

IronDeficiency SymptomsChlorosis on younger leaves. Storage roots were reduced in size and become pale in colour.

Correction MeasureFoliar spray of FeSO4@0.5%

ZincDeficiency SymptomsYoyng leaves become smaller i.e. little leaf symptoms. and become yellow in color

Correction MeasureFoliar spray of ZnSO4@0.5%

SulphurDeficiency SymptomsChlorosis occur in young leaves

Correction MeasureFoliar spray of CaSO4@05.%

Name of disorder:       Root splittingCrop:                           CarrotSplitting or cracking of carrot roots is a major problem in many carrot growing areas.  It is reported that this tendency towards is controlled by genetic factors but a number of other factors are also involved.

As clear by its name, roots get splitted making it unfit for market. Earlier cultivars split more readily than late ones (Moravec, 1961). In soils with high content of N, splitting of roots is increased. High soil

concentrations of ammonium compounds caused more serious splitting than by other forms of nitrogen.  Heavy side-dressings with NH4NO3 when the roots were 6.5 cm in diameter increased splitting, especially when nitrogen applied to widely spaced roots.

Wider the spacing, the greater chance of splitting If roots are large, there are chances of splitting as compared to small ones. Control/ Management

Follow proper management practices like right spacing and optimum amount of N application.

Prefer other forms of N fertilizer source than ammonium compounds.

Name of disorder:       Cavity spotCrop:                           CarrotSymptoms:This disorder appears as a cavity in the cortex, in most cases the subtending epidermis collapses to from a pitted lesion. Reasons:The cavity spot disorder is induced by deficiency of Ca. 

This is associated with an increased accumulation of K which leads to a decreased accumulation of Ca. 

Maynard et.al., 1963 reported that the cavity spot disorder of carrot roots is a manifestation of Ca deficiency, which may be induced by excess K uptake during the ontogeny of carrot plants. 

Control:Increase in Ca level in the growing medium leads to significant reduction in the incidence of cavity spot.

Jakobsen and Jorgensen (1986) suggested that application of fertilizer should be kept minimum and only be done in spring or early summer when the crop requires it the most .This would avoid a build up of K in the plant.