Zinc (Zn) is taken up by plants as the zinc ion (Zn2+ ) & is essential constituent of several important enzyme systems in plants. It controls the synthesis of indoleacetic acids, an important plant growth regulator. Terminal growth areas are affected first when zinc is deficient. Deficiency is most common on soils with neutral or alkaline pH that are sandy or have low organic matter content (including cut areas) & are very high in available phosphorus.
Symptoms of Zn Deficiency
Decrease in stem length.
rosetteing of terminal leaves.
Reduced fruit bud formation.
Mottled young leaves (interveinal Chlorosis).
Dieback of twigs after first year.
Sulphur(S)
Sulphur (S)
Sulphur(S) is utilised in the form of sulphate ions(SO42-). Sulphur may also be absorbed as sulphur dioxide (SO2) From the air through leaves in areas where the atmosphere has been enriched with sulphur compounds. It is not readily available from wettable sulphur which is in the form of elemental sulphur. Sulphur is a constituent of three amino acids (cystine, methionine & cysteine) & is therefore necessary for protein synthesis. It is essential for nodule formation on legume roots. Sulphur is present in oil compounds responsible for the characteristic odors of plants such as garlic and onion.
Symptoms of S Deficiency
Retarded growth rate & delayed marurity.Young leaves light green to yellowish colour. In some plants, older tissue may be affected also Small & spindly plants.
Potassium (K)
Potassium (K)
Potassium (K) Potassium (K) is taken up by plants in the form of potassium ions(K+). It remains in ionic form within cells & tissues. Potassium is essential for translocation of sugars & for formation of Starch. It is required in the opening & closing of Stomata by guard sells. Potassium promotes root growth; produces larger, more uniformly distributed xylem vessels through the root system; & increases plant resistance to disease. Potassium increases size & quality of fruits, nuts & vegetables & improves winter hardiness of perennials. Plantsthat produce large amounts of carbohydrates have a high potassium requirements.
Symptoms of K Deficiency
Slow growth.
Tip & marginal chlorosis..
Weak stems & Stalks.
Remedy
Apply potassium Fertilizer.
Phosphorous(P)
Phosphorous (P)
Phosphorous(P) Phosphorous(P) is taken up by plants as ortho-phosphate PO42- .Phosphorous is present in all living cells. It is utilized by the plant to form nucleic acids (DNA & RNA). Through energy-rich linkages (ATP & ADP), it is involved in the storage & transfer of chemical energy used for growth & reproduction. Phosphorous stimulates seedling development & root formation. It hastens matuarity& promotes seed production.
Phosphorous supplementation is required most by plants under the following circumstances
Cold water
Limited root growth period & rapid vegetative growth.
Symptoms of P Deficiency
Slow growth; stunted plants.
Purplish coloration on foliage of some plants (Older leaves first).
Dark green coloration.
Delayed maturity.
Poor fruit or seed development.
Nitrogen(N)
Nitrogen (N)
Nitrogen(N) Nitrogen(N) is taken up by plants nitrate (NO3-) or ammonium (NH4+) ions. It is utilized by plants to synthesize amino acids, the building blocks of proteins. The protoplasm of all living cells contains protein. Nitrogen is also required by plants for other vital compounds, such as chlorophyll, nucleic acids & enzymes. Chlorosis is usually more pronounced in older tissue. Since nitrogen is mobile within plants, it tends to move from older to younger tissue when in short supply.
Symptoms of N Deficiency
Slow growth; stunted plants.
Yellow-Green colour (Chlorosis).
Death(necrosis) of tips & margins of leaves, beginning with more mature leaves.
Remedy
Apply Nitrogenous Fertiliser
Molybdenum
Molybdenum (Mo)
Molybdenum (Mo) Molybdenum (Mo) is taken up by plants as the molybdateion(MoO42-). It is required by plants for the utilization of nitrogen. Nitrate nitrogen is converted to amino acids by the nitrate reductase enzyme; this enzyme requires molybdenum. In addition, molybdenum is required for the symbiotic fixation of Nitrogen by legumes.
Symptoms of Mo Deficiency
Stunting & lack of vigor.
This is similar to nitrogen deficiency, because of the key role of molybdenum in nitrogen utilization.
Poor pigmentation.
Marginal scorching & cupping or rolling of leaves.
“Whiptail” of Cauliflower.
Yellow spotting of Citrus.
Manganese (Mn)
Manganese (Mn)
Manganese (Mn) Manganese (Mn) uptake is in the form of the ion Mn+2. Manganese serves as an activator for enzymes in plant growth processes. It assists iron in chlorophyll formation. High concentrations of manganese in plants may induce iron deficiency. Manganese is generally required with Zinc in foliar spraying of Commercial citrus. Other tree crops may show deficiencies.
Symptoms of Mn Deficiency
Interveinalchlorosis of young leaves. Gradation of pale-green leaf coloration, with darker color next to veins. No sharp colour distinction between veins & inter veinal areas as with iron deficiency.
Magnesium
Magnesium (Mg)
Magnesium Plant uptake of Magnesium is in the form of the magnesium ion (Mg2+). The chlorophyll molecule, which is essential for photosynthesis, contains magnesium. Magnesium serves as an activator of many plant enzymes required in growth processes. Magnesium is mobile within plants & can be readily translocate from older to younger tissue when it is deficient. Plants need magnesium to balance the generally high use of potassium from fertiliser & manure.
Symptoms of Mg Deficiency
InterveinalChlorosis in older leaves. Curling of leaves upword along margins. Marginal yellowing, with green “ Christmas Tree” area along mid-rib of leaf.
Iron (Fe)
Symptoms
Iron (Fe) Iron (Fe) is taken up by plants as ferrus ions (Fe2+) & is required for the formation of chlorophyll in plant cells. It serves as an activator for biochemical processes, such as respiration, photosynthesis & symbiotic nitrogen fixation. Iron deficiency can be induced by high levels of manganese or high lime content in soils. Deficiencies are common in high pH soils, in situations with poor aeration, or when high levels of Zinc or Managanese are present.
Symptoms of Fe Deficiency
Interveinalchlorosis of young leaves. Veins remain green except in severe cases. Twig dieback. In severe cases, death of entire limbs or Plants.
Copper
Symptoms
Calsium (Ca) Calsium (Ca) is taken up by plants as the calcium ion (Ca++). A structural nutrient, it is an essential part in cell walls & membranes & is required for the formation of new cells. For this reason, early season availability of supplemental Calcium has a distinct effect on fruit set. Once deposited in plant tissues, Calcium is not remobilized. Therefore, young tissue is affected first under conditions of deficiency. Since Calcium is not mobile, the requirements of a crop for Ca++ after early fruit set are commonly supplied in the form of nutritional sprays.
Symptoms of K Deficiency
“Tip burn” of young leaves-celery, lettuce, Cabbge.
Death of growing points (Terminal buds). Root tips also affected.
Abnormal dark green appearance of foliage.
Premature shedding of blossoms & buds.
Weakened stems.
Water-soaked, discoloured areas on fruit-blossom-end rot of tomatoes, peppers & melons; bitter pit or cork spot of apples & pears..
Symptoms of Cu Deficiency
Stunted growth. Dieback of terminal shoots in trees. Poor pigmentation.
Dieback of terminal shoots in trees.
Poor pigmentation.
Wilting & eventual death of leaf tips.
Abnormal dark green appearance of foliage.
Premature shedding of blossoms & buds.
Calsium (Ca)
Symptoms
Calsium (Ca) Calsium (Ca) is taken up by plants as the calcium ion (Ca++). A structural nutrient, it is an essential part in cell walls & membranes & is required for the formation of new cells. For this reason, early season availability of supplemental Calcium has a distinct effect on fruit set. Once deposited in plant tissues, Calcium is not remobilized. Therefore, young tissue is affected first under conditions of deficiency. Since Calcium is not mobile, the requirements of a crop for Ca++ after early fruit set are commonly supplied in the form of nutritional sprays.
Symptoms of K Deficiency
“Tip burn” of young leaves-celery, lettuce, Cabbge.
Death of growing points (Terminal buds). Root tips also affected.
Abnormal dark green appearance of foliage.
Premature shedding of blossoms & buds.
Weakened stems.
Water-soaked, discoloured areas on fruit-blossom-end rot of tomatoes, peppers & melons; bitter pit or cork spot of apples & pears..
Boron(B)
Symptoms
Boron(B) is predominately in solution as boric acid, H3BO3, and is taken up by plants in this form.It functions in the differentiation of meristematic of meristematic cells. Boron is also involved in regulating metabolism of carbohydrates in plants. Nearly all fruiting crops have a high demand for boron in the early fruiting stage. Foliar applications are an effective way to meet this demand at this critical growth state. Recent research has shown that boron is effective in increasing pollen viability, thus controlling to increased fruit set. When boron is deficient, cells may continue to divide, but structural components are not differentiated.
Symptoms of B Deficiency
Death of terminal growth, causing lateral buds to develop, producing a “witch’s broom” effect.
The fungus survives on crop residues. They are most damaging, when the moisture is available more than 5 hrs.
Symptoms
Fungus that produces leaf spot on the base of cabbage head, cauliflower initial base leaf. In cauliflower, affects the curds and shows brown rot. The spots are initially small begin on older leaves, which shows spots surrounded by yellow discoloration. During the high disease pressure, the spots coalesce and forms a blight appearance and defoliation occurs
Control Measures
Spray Kavach / M-45 / Score @ 2g/lt of water.
Downy Mildew
Symptoms
Portions of the under surfaces of infected leaves become covered with a white to grey fluffy “down” comprised of the fungus spores. The upper surfaces of the leaves have purple, yellow or brown regions that correspond to the sporutating areas on the under surfaces of the leaves. Infected young plants may die. An early leaf infection may enter a plant’s vascular system turning it black. Cauliflower curd & cabbage heads may all become unmarketable if infected.
Control
Ridomil (1.5g/ltr. Water)
Powdery Mildew
Symptoms
First appear on older leaves as white powdery residue primarily on the upper leaf surface. Circular patches or spots appear on the lower surface of the leaves. These gradually merge & leaf surface appears to be dusted with white powder. Infection on cabbage or cauliflower can cause reduced head or Curd size. Fruits of the affected plants do not develop fully & remain small. Leaf yellowing & finally leaves dropping occurs.
Dark brown spots with concentric rings on leaves, fruits; stem gives board effect. Fruit Becomes infected, generally through the calyx or stem attachment during green or ripe stage. Fruit lesions attain considerable size, occasionally involving the entire fruit; usually have concentric ringing; mostly drop.
Infection Factors
High humidity, with frequent rain; a temperature (24-29 ° C) favors the disease development.
Lesions on fruit – large, black & canker like, become corky & resemble small scabs with irregular margins. Leaf Spots- Numerous small, angular to irregular, water soaked spots & have a yellow halo, centers dry out frequently tear.
Soil borne disease. High temperature & wet soil favours the disease development. More prevalent during high soil moisture with 19-250
Symptoms
Plant shows partial wilting, which becomes permanent & progressive, affecting more vines. Leaf shows yellowing, loose turgidity & drooping, eventually the plant dies. Roots are not affected. In older plants, leaves wilt suddenly & internally vascular bundles in the collar region become yellow or brown.
Control
Soil drenching with Topsin- M (Thiophanate methyl)-(2g/ ltr. Water) Bavistin (Carbendazim)/Companion(Carbendazim+Mancozeb)-(2g/ ltr. Water) at 5-6 days interval.
Bacterial Wilt
Symptoms
Wilting of lower leaves followed by sudden & permanent wilt of the entire plant without yellowing. Vascular browning occurs, bacterial streaming from vascular elements occurs when cross sections of the lower stem are suspended in water.
Source of infection
Infected potato tubers. Soil, perpetuates in soil for 2 years. Solanaceous crops are susceptible.
Control
Soil drenching with Streptocycline (6gm/10 ltr. Water) Blitox (Copper ony chloride)- (2-3gm/ ltr. Water)
Seed borne bacterial disease & also lives in soil and crop debris. High humidity and warm climate, needs moisture during the night / morning
Symptoms
Yellow-orange v-shaped lesions that occur along the cotyledon and leaf margins. The yellow tissue turns to yellow-brown and the lesion progresses to a V-shaped area with the base of the V toward the leaf centre. Once the symptom advanced, entire plant shows dried leaf, under higher moisture plant rots. In cabbage, heads are smaller and lower leaves may fall off.
Yellow coloured veins in leaves. Leaf turns completely yellow. In extreme cases leaf become totally light yellow or cream coloured & there is no trace of green colour.
Leaf size is reduced & plants remain stunded. Twisting of main stem & lateral branches. Bending of plants appears to be creeping on the soil surface. Twisting of leaf petiole is conspicuous. Leaves become thick & leathery in structure. Severe cases new leaves also exhibit bold enactions, thickening & curling. Fruits are few with pale yellow colour deformed, small & tough in texture.
Dark coloured dry rot on the end of the fruit where the flower was. The problem is caused by a lack of calcium in the developing fruit.
Control
Calcium Nitrate / Calcium Chloride.
Fruit Rot
Symptoms
Symptom starts when the fruit starts ripening. Water soaked sunken lesions & rapidly expand. Fully expanded lesion are sunken & range from dark red to light tan coloured. Later the fruit starts rotting.
Spread
The diseases is severe when the ripening coincides with rains / during rainy season with over head irrigation. The pathogen survives in the soil & crop details.
Control
Good water management.
Spray M-45 /Kavach @ 2g/ ltr water.
Fuzziness
Symptoms
Appearance of hairy structure on the curd is characterized by fuzziness which results from any temperature higher or lower than the optimum required for a particular cultivar or too large a temperature fluctuation during the curd development.
Pinking
Pinking
The purple colour is due to formation of anthocyanins also found in red cabbage.
Bracting
Bracting
High temperatures shortly after the start of the curd formation may cause appearance of small leaves in the curd.
Riceyness
Riceyness
Curds to become uneven & Fuzzy. Low temperature just after planting, warm temperatures during curd development. Late supply of nitrogen to plants. Premature initiation of floral buds results from any temperature higher or lower than the optimum required or too large temperature fluctuation by irrigation during the curd development.
Buttoning
Buttoning
Any check in the vegetative growth of the seedling may induce buttoning. Transformation from vegetative to curding of cauliflower is dependent on temperature. Late planting of tropical early varieties causes buttoning.
Peanut Bud Necrosis Virus (TOSPO/PBNV)-Thrips
Symptoms
Bronze colour marking on upper leaf. Downward curling. Necrotic spots. Stiffening & upward rolling of leaves. Shoots necroses. Wilt & Die. Fruits- yellow spots with concentric bronze colour, red 7 yellow bands on ripened fruits.
Root Knot Nematode Very active in sandy soil & having very wide host range. Survive in the soil for long period in the form of egg masses. Affected plant results in stunted growth. Wilting of the plant during hat & water stress. Form root knots & result in failure of overall plant growth.
Control
Deep ploughing during the hot summer.
Application of Neem Cake.
Soil Fumigation.
Mites
Nature of Damage
These are found in large numbers in the ventral side of the leaves under the protective cover of the web. Both nymphs suck the sap & devitalize the plants causing murda complex. In severe cases infested fruits become brownish & hard skin.
Colonies of mites are found feeding on the ventral surface of leaves under fine silken web protective cover. The affected leaves turn yellow & curl & gradually crumpled. During severe infestation the fruits & entire plant affected. Warm temperature favors higher multiplication.
Attack on leaf upper surface & photosynthesis get affected & hence the yield.
Control
Vertimac @ 2ml/ ltr. Water..
Aphids
Nature of Damage
The nymphs & adults suck the sap from the leaves & from the tender young growing fruit tips. The affected leaves would have honey, which attract sooty molds
Control
Confidor / Actara/ Acephate/ Pride @ 1ml/ ltr. Water
Thrips
Nature of Damage
Both adult & nymphs lacerates the tissue & feed on the young leaves,becomeupword curled & brittle. Fruits would show scars. Transmit Tospovirus.
On hatching, young larvae feed by scraping epidermal leaf tissue producing white membranous patches. Advance stage larvae bite the leaves & makes small holes. In severe condition, leaf completely damages with holes.
Control
Spray success @ 0.5ml/ ltr or Avaunt @ 1ml/ ltr.
Pod Borer
Nature of Damage
Larvae feed on the leaves making holes in the lamina. Caterpillars also feed on the seeds by making irregular holes in the pods. These are nocturnal in habit & remain hidden in the soil or in the leaf canopy in the day.
The insect lay the egg singly on fruits, flowers & shoots. The newly emerged larvae tender fruits & shoots. Affected shoots wither & droops drown. With the formation of flower & fruits, the larvae bores in to the tender plant parts & damages the internal fruits & affects the fruit quality.
