Citrus presentation

citrus and its classification

1. CITRUS SUBMITTED TO- Dr. Dilip Singh Kachwaya SUBMITTED BY- Vaishali Gautam 195131 M.Sc. Fruit Science

2. INTRODUCTION BOTANICAL NAME Citrus spp . FAMILY Rutaceae CHROMOSOME NUMBER 2n=18 TYPE OF FRUIT Hesperidium EDIBLE PART Juicy placental hair TYPE OF POLLINATION Self pollination RATE OF RESPIRATION Non climacteric TYPE OF BEARING HABIT Mix bearing

3. KINGDOM Plantae DIVISION Tracheophyta CLASS Magnoliopsida ORDER Sapindales FAMILY Rutaceae GENUS Citrus SPECIES aurantifolia, limon, nobilis etc. TAXONOMY:

4. ORIGIN CITRUS SPECIES China Sweet orange, Mandarin India Kagzi lime South east Pummelo, Lemon ORIGIN:-

5. AREA AND DISTRIBUTION: - India ranks sixth in the production of citrus fruit in the world. Other major citrus producing countries are Spain, USA, Israel, Morocco, South Africa , Japan, Brazil, Turkey and Cuba. It occupies third position after mango and banana in the production of fruits in India . In India citrus is cultivated over an area of near about 923.2 thousand hectares with an estimated production of 8607.7 thousand metric tones. In Punjab citrus occupies 39.198 hectares with annual production of 734699 MT. Kinnow occupies 54.9% of the area under citrus . Citrus is cultivated in states like Andhra Pradesh, Maharashtra, Punjab, Madhya Pradesh, Gujarat, Rajasthan, Karnataka, Orissa, Bihar, Assam.

6. Largest producer in the world in citrus species COUNTRY FRUIT CROP CHINA Mandarin INDIA Acid lime ITALY Lemon BRAZIL Sweet orange USA Grape fruit , Pummelo

7. IMPORTANCE Citrus fruits not only do they contain large amounts of vitamin C but are also rich sources of antioxidants, vitamin A and potassium. Citrus peels are rich in pectin, valuable in making jellies, marmalades, candies, jams and pharmaceutical preparations. LEMONS : Lemon is one of the super foods that come with a myriad health and cosmetic benefits. Lemon juice adds flavor to tea or even freshen breath. It makes your tea healthier as tea is rich in a class of antioxidants called flavonoids. Lemon juice is also used to remove stains and odors from clothes and cutting boards. Lemon being a citrus fruit fights against various infections. Some of the health benefits from lemon are: Lemon juice is said to give a amazing glow to the skin. Lemon lowers blood pressure and increases the levels of HDL (good cholesterol).

8. ORANGES: They are rich sources in vitamins A and C, flavonoids, antioxidants, calcium, magnesium, potassium, dietary fiber etc. They are known to have anti-inflammatory, anti-tumor and anti-oxidant properties. Some of the health benefits include, Relieve constipation as they are good source of dietary fiber, Regulates high blood pressure as magnesium helps to maintain blood pressure . The high amount of vitamin C and flavonoids protects against heart diseases, Iron and vitamin B6 in oranges help in purify the blood. Calcium in oranges help in keeping the bones and teeth strong, Beta-carotene, a powerful antioxidant protects the cells from being damage etc .

9. CONTENT Orange Grapefruit Tangerine Weight (g) 131 236 84 Energy (kcal) 62 78 37 Fibre content (g) 3.1 2.5 1.7 Ascorbic acid (mg) 70 79 26 Folate (mcg) 40 24 17 Potassium (mg) 237 350 132 . NUTRITIONAL VALUE

10. CLIMATE REQUIREMENTS Citrus plants grow well in tropical and subtropical climates and can stand light frosts occasionally. The average temperature for good growth is about 16 to 20° C . It grows well in drier areas having rainfall upto 500mm to hilly areas having 2500 mm of rainfall . Mandarins prefer more humid and tropical summer climate with warm winter and high rainfall. Limes and lemons require warm and moderately moist conditions for its growth.

11. SOIL REQUIREMENTS Citrus trees grow in almost any soil that is well-drained, sufficiently aerated and allows tap root to penetrate to the desired depth . Citrus can be grown in a wide range of soil types provided they are well drained. Fertile, well-aerated soils with a pH of between 6 and 6.5 are ideal. The growth, development and production of a plant depend on the physical characteristics of the soil such as drainage, density, texture, water-holding capacity, structure, soil depth, the homogeneity of the profile and the degree to which water can infiltration in the soil.

12. BOTANY Plant: They are small, spiny shrubs or trees with alternate, usually evergreen, leaves, which are shiny and leathery and dotted with oil glands. The stems are mostly winged and jointed with the leaves and there is usually a spine on the twigs at the attachment of each stem. Flower: Flowers smell sweet and they have five petals that are white and some kinds have purple staining in the outer surfaces. Fruit: The fruits are spherical or egg-shaped and have 8-14 juicy sections containing large, white or greenish seed leaves (cotyledons ).

13. VARIETIES GROWN IN VARIOUS STATES

14. FRUIT SCIENTIFIC NAME Sweet orange Citrus sinensis Mandarin Citrus reticulata Grapefruit Citrus paradisi Lemon Citrus limon Lime Citrus aurantifolium The five commercially important citrus fruit crops: MINOR CULTIVARS Pummelo Citrus maxima Citron Citrus medica Tahiti lime Citrus latifolia

15. 1 . Citrus reticulate (Sangtra or Mandarin) - Upright growing tree can grow up to height of 5 meters . - Trees are less spreading . - Leaves lanceolate in shape with narrowly-winged petioles . - Flowers are of medium sized. - Fruits globose in shape with loose peel - Seeds are small with greenish cotyledons.

16. VARIETY CHARACTERS COLOUR &SEEDS TSS ( %) YIELD/PLANT PAU KINNOW-1 (2016) Mid season variety, matures in January, low seeded, sweet flavour Orange colour and 0-9 seeds per fruit 10.5 45 kg DAISY (2013) Cross between FORTUNE and FREMONT mandarin, early maturing, matures in November, weight is 210 g Dark orange in color & 10-15 seeds per fruit 11.5 57 kg W.MURCOTT (2013) Tree is moderate in size, fruit is usually flattened with a thin, smooth, mid season variety, matures in January, weight is 201 g Orange rind easy to peel and contains 10 seeds/fruit 9.6 57 kg KINNOW (1968) Fruit medium globose to oblate, matures in January Golden orange in colour and contains 12-25 seeds/fruit - 125-150 kg LOCAL (19680 Fruit small to medium in size, oblate to sub globose, slightly acidic, matures in December - January Skin cardmium yellow, seeds 3-7 - - MANDARIN VARIETIES

17. W.MURCOTT DAISY

18. 2. Citrus paradisi (Grape Fruit) - Trees are large spreading with bigger-sized foliage.( height 30-50 feet) - It has a round, thick head of foliage. Its leaves are large, egg-shaped (ovate) and blunt pointed. - Petioles are broadly winged. - Flower size is also bigger than sweet oranges - Fruit is yellow coloured with thick rind. - Seeds are large in size few to many per fruit, juice usually acidic.

19. VARIETY CHARACTERS FRUIT COLOUR SEEDS/ FRUIT YIELD( kg) STAR RUBY (2009) Trees medium in size, fruit size small to medium, shape oblate-roundish, peel smooth, early variety Glossy yellow having distinctly bright red blush seedless 53 RED BLUSH (1995) Fruits small to medium, oblate, peel smooth, mildly acidic , matures in last week of November Deep yellow having crimson colour 0-8 76.5 MARSH SEEDLESS(1968) Fruit medium to large, oblate, roundish Light yellow 0-6 92.8 DUNCAN (1968) Fruits large, oblate, ripens in January Pale light yellow or creamy 40-50 84 FOSTER (19680 Fruit medium to large, oblate, ripens in November - December Pale yellowish 40-50 51.4 GRAPE FRUIT VARIETIES

20. 3. Citrus aurantifolia ( Lime) - Tree is medium sized with sharp and stiff numerous spines. - Small leave with narrowly winged petiole - Flowers are small, white in colour. - Fruits greenish yellow , thin- skinned, seeds small and highly polyembryonic having greenish cotyledons . The juice vesicles are also greenish in tinge. - The fruit is used in much the same way as Lemon

21. LIME VARITIRES Kagzi : fruit small, round and thin skinned, pulp greenish white, juice strongly acidic.

22. 4. Citrus sinensis (Sweet orange ) -Trees are of medium size with rounded tops.( 25-40 ft) - Leave medium in size bigger than reticulate. - Petioles are narrowly winged. - Flowers are small in size. The skin of fruit is tight with lines. - Fruits sub-globose or flattened globose. Seed few too many usually bold in size (polyembryonic)

23. VARIETY FRUIT FRUIT COLOUR RIPENING PERIOD YIELD/ TREE NO. OF SEEDS/fruit VALENCIA (1968) Medium , slightly oval, juice abundant, rich in taste Skin deep golden yellow Feb- march 38.9 kg 2-7 MUSAMBI (1962) Small to medium, sub globose, juice has low acidity, apex marked with circular ring Flesh pale yellowish or whitish November 41.3 kg 20-25 JAFFA (1962) Medium to large, round to oblate , acidity and sweetness well blended, flavour rich, Skin orange - red December 54 kg 8-10 BLOOD RED (1962) Medium to large, roundish to slightly oblong, rind thin, rich flavour in sweetness and acidity well blended Deep orange December – January 42.3 kg 8-10 VARIETIES OF SWEET ORANGE

24. 5. Citrus limon ( Lemon) This is a small, widely branched tree that grows 10 to 20 feet high. It is thorny and evergreen and its leaves are narrow and ovate and light green. The flower buds are in pairs or single. They are tinted purple. The petals are white inside and purple on the outer surface. The fruit is usually pointed at both ends and light yellow. Its flesh is light and its juice sacks are thin. The seeds are ovoid and smooth. The Lemon is grown for its acid juice, which is used in flavoring and in making various drinks. Lemon peel is candied. EUREKA

25. LEMON VARIETIES PUNJAB BARAMASI LEMON (2008) : tree spreading and vigorous, fruit medium to large, spherical in shape, peel smooth, fruit very juicy with low seed content and matures in the first week of July. YIELD- 84 kg / tree PUNJAB GALGL (1994) : Trees are vigorous, fruit medium in size, oval in shape, peel is smooth, glossy, medium thick and yellow at maturity , juice has 5.2 % acidity and 5-8 seeds per fruit. It matures in last week of November . YIELD- 80-100 kg / tree EUREKA (1968) : Fruit medium oblong, skin lemon yellow, smooth, juice abundant, strongly acidic with e xcellent flavour, seeds rarely present ripens in august – September.

26. PUMMELO- This large tree has a round top with fuzzy twigs when young. Its huge leaves are ovate. The white flowers are borne singly or in bunches. The fruit is the largest of all Citrus. It is globose, oblate or moderately pear-shaped with 11-14 sections. The pulp is light colored or pink and coarse with large, spindle-shaped juice sacks that separate easily from one another. It is closely related to the Grapefruit, but much less cold resistant

27. Citrus limetioides (Sweet Lime ) - Tree is of medium size with spreading and somewhat dropping habit . - Leaves light green in colour, with serrated margins. - Big thorns present in axils of leaves. Flowers scented. Fruits medium in size globose remain green at ripening also VARIETY LOCAL(1968) – Fruit medium, globose to ellipsoid, rind smooth with distinct aroma, juice abundant, lacking in acidity, seeds 5-6 ripens in the beginning of September.

28. ROOT STOCKS :- 1 . Citrus jambhiri lush : Rough lemon (Jatti khatti )- It is the most widely used rootstock in North India. It needs less water, suits arid conditions. Tree is medium in size, with sharpened strong spines. Fruit round in shape with irregular peel . Seeds bold and many upto 32, higtily polyembryonic may have 4-6 embryos. 2 . Citrus Khama Khatta (Khatta ):Tree is of medium size spreading than jatti khatti. Leaves are bigger than jatti khatti but are green in colour. Flowers coloured. Fruit medium-sized become orange coloured at ripening . Seeds 30-34 rarely polyembryonic. There may be 2 or 3 embryos in few seeds. 3. Citrus reshni tanaka (Cleopatra ):Attractive tree with symmetrical growth. Thorns are absent. Leaves small but dark green in colour. Flowers are smaller than jatti khatti and Khama Khatta . Fruits small, orange, loose skinned. Average number of seed per fruit 14. Seeds are highly polyembryonic. Very good rootstock for commercial citrus cultivars particularly Kinnow and sweet oranges . 4 . Rangpur lime ( C. limonia): This root stock has proved very successful for raising some sweet orange and mandarin orange varieties This root stock is resistant to Tristeza virus but highly susceptible to exocortis.

29. PROPAGATION Mandarin orange is invariably propagated by seed . Sweet orange, grape fruit and mandarin orange are invariably propagated by shield budding in spring . Other citrus fruits like lemon, lime and citron are usually propagated by air layering or sometimes by hard wood cuttings, although air layering is preferred for commercial plantation. Layers are prepared in rainy season, and they are planted in late rain or in next monsoon season. .

30. ESTABLISHMENT OF COMMERCIAL ORCHARD AND AFTERCARE: Preparation of the Soil After selecting the suitable location and site for establishing the orchard, some preliminary operations pertaining to the preparation of the soil have to be done lik e ploughing, leveling, manuring, formation of roads, irrigation channels, drainage and fencing. Planting Material It is very important to select healthy and disease-free planting stock in case of citrus. Further , vegetative propagation provides fruit of uniform size and quality. . Rangapur lime is resistant to the Tristeza virus, besides being salt and drought tolerant. In case of acid lime and lemons, research shows that the Gajanimma rootstock has been proved highly suitable for higher fruit quality and productivity.

31. Layout of citrus orchard : The square system of layout is commonly followed for planting the citrus crop. -Citrus trees should be planted in straight rows . Preparing the pits : Pits of ½m x ½ m x ½m size may be dug at required distances 3-4 weeks prior to planting. Dusting of 10% BHC or Aldrex on the inner sides of the pit and also mixing 100g of Aldrex or BHC dust in the soil prevents white ant (termite) infestation . Each pit should be filled with only topsoil mixed with 50 kg of well-decomposed cattle manure and 1-2 kg of super-phosphate. The pit should be watered after filling so that the soil mixture settles down.

32. Planting: In low or scarce rainfall regions, planting should be done at the beginning of the monsoon season (June/July ) so that the humid weather helps the young plants to get established fast. In areas of high rainfall, (1000 mm and above) planting should be done at the end of the south-west monsoon season (October-December .) Care Of Young Plants The newly planted young plants must be protected during the initial 3 to 4 years form excessive heat, moisture and cold. Such stems may be protected by white washing the stems rather than by wrapping them with paper or such other material. For protecting the young plants from low temperatures and at times from frost, their trunks may be wrapped with gunny cloth or any other durable material.

33. PLANTING SEASON AND SPACING SEASON OF PLANTING : The ideal time for planting the grafts is during June - July just after the first monsoon showers SPACING : Spacing adopted for planting citrus varies depending on variety and agro climatic conditions. However in general the following spacing are adopted : Sweet orange (Mosambi ) 6 x 6 m Orange (Coorg and Nagpur mandarin ) 6 x 6 m Lime and Lemon 5 x 5 m

34. PLANTING DENSITY Mandarin (Citrus reticulata ) Normal spacing – 6 m x 6 m Plant population – 277 / ha Sweet orange (Citrus sinensis) Normal spacing - 5 m x 5 m, 5.5 x 5.5 m Plant population – 400/330 per ha Limes/lemons (Citrus aurantifolia & Citrus limon ) Normal spacing – 6 x 6 m / 5 x 5 m Plant population – 277/400 per ha In light soils, spacing will be 4.5 x 4.5 m or 5 x 5 m

35. IRRIGATION The critical period for irrigating citrus trees is during summer when frequent light irrigation helps to lower soil temperature and to raise humidity . In fact , irrigation should be so scheduled that the plants are watered few days before the onset of flowering and it is repeated again after the fruit-set . Application of irrigation is equally important at the time of fruit maturity so as to avoid shrinkage of fruits and drying of pulp . Shortage of water during these two stages may result in the shedding of flowers and newly-set fruits. Watering at 5 to 6 days interval during summer and every 10 to 12 days during winter is quite effective .

36. NUTRIENT MANAGEMENT In Kinnow annual application of FYM – 100 kg/ tree Nitrogen - 400-800 g/ tree Phosphorus - 200 g/ tree Foliar application of ZnSO4 0.3 % in A pril, June and September are recommended.

37. INTERCROPPING:- In citrus intercropping can be done through out the juvenile period. Indiscriminate growing of intercrops like potato should be avoided. Leguminous crops like, peas, moong, mash, grams should be grown leaving the plant basins. If wheat is to be sown, separate irrigation system should be prepared for the plants to provide irrigation during March-April when wheat doesn’t require irrigation . Chilies, Barseem and Jowar/Maize should not be grown in citrus orchards.

38. WEED MANAGEMENT:- Both dicot and monocot weeds infest the citrus orchards. Deep ploughing injures the feeder root system which ultimately heads for the tree decline. Hoeing should be done only once in a year to remove the weeds.. Use of Weedicides: It is a cheap method of weed control in citrus orchards. Pre-emergence application of Diuron (5 kg/ha) or terbacil (4.5 kg/ha) or Atrazine (5-6 kg/ha) keep the weeds under control. Annual weeds can be controlled by spraying at their flowering stage with Gramaxone 24 WSC (paraquat) @ 6-7 ml/L of water. Similarly baru grass and woody weeds may be killed with the spray of round up Glycel 41 SL (Glyphosate) @ 10 ml/L of water.

39. MULCHING Mulching in basins of sweet orange trees with paddy husk or dry leaf to a depth of 8 cm not only reduces the weed growth and number of irrigations and provides organic manure after decomposition but also improves the yields and fruit quality .

40. REGULATION OF FLOWERING Bahar Treatment - Due to the absence of low temperatures in Central India, The natural flowering of citrus trees is of very less intensity. Therefore the flowering is usually forced by withholding irrigation water . For forcing the trees to flower during February-March (ambebahar), the water supply to the trees is withheld for 40 to 60 days, i.e., from 15th November to end of December until the leaves show symptoms of temporary wilting . For Mrig bahar (July flowering), about 40 to 50 days water stress (25% leaf drop) during May-June is sufficient to force the trees to flower.

41. TRAINING AND PRUNNING In Citrus pruning is done to develop a strong framework in the beginning. Most citrus trees benefit from being pruned every two to 5 years. Pruning is best done in the early spring or in the early fall. Branches growing upto 45 cm from the ground are removed leaving a clear straight stem. 4 or 5 well-spaced branches are retained forming a thick bushy crown, which protects the stems and branches from the effects of sunshine. The bearing trees require support, as due to heavy bearing the branches tend to break. Usually the support is given by erecting a bamboo frame around the plant at a height of 2 - 2.5 m and the branches are tied with the help of rope to the structure

42. NUTRITIONAL DISORDERS

43. 1. RIND SPLITTING CAUSE- due to sudden rain after long dry spell SYMPTOM- Splitting may be radial or transverse - more severe in thin rind mandarins CONTROL - Use potassium fertilizers

44. 2. LEAF MOTTLING OR FRENCHING CAUSE - Zinc deficiency or also known as foliocellosis SYMOTOMS - Initial stage parts adjoining mid rib and veins remain green. Severity-chlorotic, small, narrow, pointed leaves. CONTROL - Foliar spray of zinc sulphte@ 0.5%

45. 3. EXANTHEMA OR DIE BACK CAUSE- Copper deficiency SYMPTOM – Wilting of terminal shoots followed by death of leaves - dieback starts from twigs - gum pockets develop on fruit CONTROL - Bordeaux mixture can be used.

46. 4. ALBEDO BREAKDOWN OR CREASING CAUSE- multinutrients SYMPTOMS - Irregular grooves and furrows in rind more on shaded side of fruit -seen in naval oranges CONTROL – Pre harvest spray of calcium

47. 5. GRANULATION Granulation is a condition in which the juice sacs shrivel because of gel formation. It occurs more in large fruit, on young trees, in humid climates and on trees growing on sandy soils

48. 6. OLEOCELLOSIS It is caused by rind oil release when oil cells get ruptured during harvesting or during handling from the field to the pack house. It is more common in crop taken in 'Mrig' bahar and harvested during February-March. Careful harvesting and handling reduces incidence of oleocellosis. Rind oil from ruptured cells discolours the skin making the fruit unmarketable. Control : Best way to reduce its incidence is to cure the fruit overnight at a temperature of 18-20 C for 12-24 hrs., before the fruit is moved from the field to the pack house.

49. 7. FRUIT DROP The causes attributed to fruit drop in citrus are lack of fertilization, mechanical shock, insects, disease, high temperature, rainfall, and defective irrational practices. The most pronounced stages of fruit drop occurs when the fruits are at marble stage. It lasts for a month after full bloom . On the onset of hot summer weather during May-June the second wave of intense fruit drop occurs while pre-harvest drop occurs during ripening period, which lasts from August-January. Control : The method of control depends upon the causes of the drop and the variety of the fruit. In order to reduce the pre-harvest drop, NAA (10 ppm) is sprayed from August till October at monthly interval.

50. PESTS AND THEIR MANAGEMENT

51. 1.CITRUS LEAF MINOR ( Phyllocnistic citrella ) SYMPTOM OF DAMAGE: -Making silvery appearance presence on the lower surface of leaves. -Leaves – distorted and crinkled. -Severe infestation causes defoliation. CONTROL MEASURE: Spraying of monocrotophos [Nuvacron] 1.5ml, fenvalerate 0.2ml or dimethoate [Rogor] 2ml mixed in a liter of water at weekly intervals at the time of emergence of new flush . Citrus leaf miner

52. 2. CITRUS PSYLLA ( Diaphorina citri ) SYMPTOMS OF DAMAGE -Both nymph and adult suck cell sap from buds, leaves and young shoots as a consequence the leaves get curled and shoots start drying. -It act as a vector of greening disease. CONTROL MEASURES Spray 1250 ml Rogor 30EC or 6.25 l MAK HMO in 500 l of water per acre during March and again in first week of September. INSECT CURLED LEAVES

53. 3. CITRUS WHITEFLY ( Dialeurodes citri ) SYMPTOMS OF DAMAGE - Both nymph and adult suck the cell sap from tender leaves and shoots and reduce the vigour. - infested foliage turns yellowish green, becomes curled and finally shed. - sooty mould developed on honey dew, gives black appearance to foliage. CONTROL MEASURES Spray 1000 ml Fosmite 50 EC or triazophos 40 EC in 500 l of water per acre during April-May and again during September-October.

54. 4. APHIDS ( Toxoptera aurantii, Aphis gossypii) SYMPTOMS OF DAMAGE Severe curling and deformation of young leaves resulting into stunted growth. CONTROL MEASURES Spray 1250 ml Rogor 30EC or 6.25 l MAK HMO in 500 l of water per acre during March and again in first week of September.

55. 5. CITRUS THRIPS ( Scirtothrips citri) SYMPTOMS OF DAMAGE - Nymphs and adults lacerate the leaf tissue and suck the sap from fruits - Leaf curling - Ring like appearance on the fruit - Irregular mottled patches on rind CONTROL MEASURE -Collect and destroy the damaged plant parts. - Spray malathion 0.05% or monocrotophos 0.036% or carbaryl 0.1 % -Encourage the activities natural enemies such as Syrphids and Chrysopid.

56. 6. MEALY BUG ( Planococcus citri ) SYMPTOM OF DAMAGE - cause damage to leaves, shoots, twigs, branches and fruits. - Both nymphs and adults suck the sap from the cells of tender branches and fruits turn pale colour - In severe infestation the flowers do not form fruit - drying up of tender shoots CONTROL MEASURE - Debark branches and apply methyl parathion paste. - Use sticky trap (5cm length) on fruit bearing shoots - Spray dichlorvas 0.2% in combination with fish oil rosin soap 25g/lit. - Field release of Australian lady bird beetle Cryptoleamus montrouizeri 10 per tree.

57. 7. FRUIT FLIES ( Bactrocera dorsalis ) SYMPTOM OF DAMAGE Fruit fly flies punctures the fruit at color break stage and deposits its eggs below the epicarp . The punctured fruit portion start rotting and fruit fall down. CONTROL MEASURE Fix fly traps @16 traps/acre in the second week of august.

58. 8. FRUIT SUCKING MOTH (Otheris maternal ) SYMPTOM OF DAMAGE - Adult pierce the fruit and suck the juice Rottening at the feeding site. - Fruit dropping CONTROL MEASURE - Apply smoke to prevent adult moth - Trap crop – growing tomato crop in orchards to attract the adult moth - Dilute suspension of fermented molasses and malathion 0.05% ( 50 EC at 1ml/lit) - Use light trap or food lure to attract moths.

59. 9.MITES ( Tetranychus sexmaculatus ) SYMPTOM OF DAMAGE - mites feed on leaves, makes multiple grey spots, weaken the leaves and cause defoliation. CONTROL MEASURE For control of red spider mite and oriental red mite, insecticides like monocrotophos (0.05 percent) and Dicofol (0.05 percent) have been found to be effective.

60. DISEASES AND THEIR MANAGEMENT

61. 1. GUMMOSIS/FOOT ROT ( Phytopthora parasitica ) SYMPTOMS - this disease commonly occurs at the base of the tree trunk near ground level. -The main symptom is that the bark on the trunk of the affected tree exudes gum slowly and cracks into small chips. Later, the bark dries and falls off, exposing the wood below it . - However , root-rot destroys a major portion of the root system and ultimately the trunk and the roots start drying . -Mandarin orange, sweet orange, grapefruit and lemon are high susceptible . CONTROL MEASURES - Drenching of affected area with auro fungin (1g antibiotic in 10 ml soap solution or water) or spraying of 0.1 percent auro fungin gives effective control. -In this, the trunk should be painted every year with Bordeaux paste up to a height of 75 cm to 1 meter. - During rainy season, the trees should be regularly sprayed with copper fungicides like Bordeaux mixture (4:4:50 or 5:5:50), blitox-50 . 

62. 2. CITRUS CANKER ( Xanthomonas axonopodis pv citri ) SYMPTOMS - Spots first become evident on the lower surface, and as the disease advances, the surface of the spot becomes white or greenish and finally ruptures, exposing a light brown, spongy central mass, resulting in a crater-like formation. Old lesions become corky brown. - These spongy, rough eruptions may be scattered over the surface of the fruit . It spreads in a wet climate. CONTROL MEASURES - spray 4:4:50 Bordeaux mixture Spraying of plants with the antibiotic streptomycin sulphate (500-1000 ppm) or phytomycin (2500 ppm) in aqueous solution together with Glycerine (1%) at 15 days intervals effectively checks the disease. Mandarin orange is fairly tolerant to this disease.

63. 3. CITRUS SCAB ( Elsinoe fawcetti ) SYMPTOMS – It appear as a small, dark brown, rough, irregular, raised lesions mostly on the under side of the leaves. - In later stages leaves often become distorted, wrinkled, stunted and deformed On the fruit, lesions consist of corky projections, which often break into scabs. CONTROL MEASURES - The diseased leaves, twigs and fruits should be collected and destroyed. Spraying of Bordeaux mixture or Blitox (0.3 %) is quite effective.

64. 4. ANTHRACNOSE ( Collectotrhicum gloeosporioidies) SYMPTOMS - brown, pimple like cloudy spots occurs on the mature leaves . - The twigs shrivel and assume a silvery grey appearance. disease leads to defoliation and drying of the tips of twigs, it is called wither tip. The main symptoms of the disease are shedding of leaves and die back disease of twigs. CONTROL MEASURE - The affected branches should be pruned off, and the trees sprayed with Bordeaux mixture (3:3:50). Spraying with Fytolan or blitox at the rate of 0.3 percent (45 g in 15 l of water for one tree) can control this disease.

65. 5. CITRUS GREENING ( Candidatus liberibacter asiaticus) SYMPTOMS - is yellowing of midribs and lateral veins of leaves. - In the growing season, upright and weak shoots with bushy growth appear. - The leaves on such twigs show various degrees of discoloration, indicating a deficiency of zinc and iron. - The affected shoots may flower prematurely and the fruits show conspicuous sun blotching (yellow patch) on the side exposed to sun. CONTROL MEASURE – Use disease free varieties.

66. 6. TRISTEZA (Citrus tristeza virus ) SYMPTOMS - Tristeza literally means a sad appearance of the tree. - The tree looks chlorotic and sickly in early stages and dies suddenly. -Distinct vein clearing and stem pitting can be observed in this disease. CONT ROL MEASURE - Using resistant or tolerant root stocks such as rough lemons, Cleopatra mandarin, R angpur lime, etc. is the only measure to avoid infection. -Transmission can be checked by using suitable insecticides to control insect vectors

67. 7.RING SPOT ( Citrus ring spot virus ) SYMPTOMS – yellow rings on mature leaves. The rings may coalesce to form bigger patches by covering entire leaf. Plant shows die back and decline symptoms. CONTROL MEASURE – Use virus free plants for raising citrus orchard.

68. 8. POWDERY MILDEW ( Oidium tingtaninum ) SYMPTOMS - Leaves and tender shoots are mostly affected by the fungus. - Profuse white powdery growth occurs on both the surfaces of leaves. - The affected leaves become badly distorted in shape and reduced in size. MANAGEMENT - Dusting with fine powdered sulphur during early morning for a better adhesion on the wet leaves, or spraying with thiovit (0.5 kg in 100 l of water) can effectively control this disease.

69. HARVESTING There are two main crops in mandarins and sweet oranges . One is called as Ambebahar (mango flowering ) the flowering of which occurs in the month of January (at the time of flowering of mango hence the name ambia) the fruits of which are available in the months of October-December The other crop is Mrig bahar ( Monsoon bloom ) the flowering of which occurs in the month of June-July and the fruits are harvested during February-April . Mandarins and sweet oranges normally take 240-280 days to arrive at maturity . Mature fruits at colour break stage are picked up in 2 - 3 intervals of 10-15 days . Limes and lemons take 150-160 days for maturity . There may be 2 or 3 crops in a year in limes and lemons.

70. Normally the bearing starts from 4 year onwards. However, the commercial yield can be obtained from 6 year onwards. The period of maturity is shortest in lime (5-6 months), longest in mandarins and sweet oranges (9-10 months) which is further influenced by heat and moisture. The maturity in sweet orange ( Citrus sinensis ) is indicated by the change of the skin colour from dark green to light yellow. The outer skin get shiny appearance and the oil glands are visible. The hard texture of the rind becomes softer on maturity. Mandarin orange( Citrus reticulata) is harvested when 75% of fruit surface colour changes from dark green to yellowish orange . Limes ( Citrus aurantifolia ) and lemons ( Citrus limon ) are harvested when the colour of the skin changes from dark green to yellowish green .

71. POST HARVEST HANDLING Grading: The fruit are inspected and unripe, immature, undersized, damaged or decayed fruits are discarded. For local markets, the citrus fruits are graded as per the size into small, medium and large grades. Packaging: Citrus fruits are packed in sacks, bags, bamboo baskets and wooden boxes for sending to local markets. For urban markets, citrus fruits are packed in telescopic cardboard boxes. Corrugated trays are equally effective as packaging material while transporting the fruits . Normally a box size of 49.5 x 29.5 x 17.5 cm having 10 kg capacity is recommended. The boxes must have 5% area punched as holes for ventilation. Storage : After the fruits are harvested, they should be treated with wax to reduce post harvest damage. Treatment of fruits with Bavistin (1000 ppm) can reduce post harvest losses and extend the shelf life to 25-26 days even at room temperature.

72. Transport: Citrus fruits are transported by rail or road as ordinary cargo and without refrigeration, which often leads to heavy loss due to decay and fungal infections. Cool Chain is essential during the transport of export quality commodity all the way from the farm to the customer. The various stages of the cool chain are : 1 . Cold store at the farm. 2 . Refrigerated truck from farm to the airport 3 . Cold store at the airport . 4 . Building up of the pallet in a cold store at the airport . 5 . Loading the aircrafts directly from the cold store in a short time 6 . Cargo aircraft maintains cold store temperature in hold . 7 . Off loading direct into a cold store in the receiving country . 8 . Refrigerated truck to the customers.

73. YIELD Mandarin : Commences from the 5th year with about 50 fruits per tree and stabilizes in the 8th year. Average production is about 700-800 fruits per tree after stabilization. Sweet Orange : Commences from 5th year with 40-50 fruits per tree& stabilizes around the 8th year. Average production is about 500-600 fruits per tree after stabilization. Lime/Lemon : Commences from the 3rd year with 50-60 fruits per tree & stabilizes in the 8th year. Average production is about 1000-1500 fruits per tree after stabilization. Economic life of plantation: 15 to 25 years

74. REFERENCES- PACKAGE OF PRACTICES FOR CULTIVATION OF FRUITS (PAU, LUDHIANA) http:// www.ikisan.com/ap-Citrus-disease-management.html SlideShare megapib.nic.in nhb.gov.in

75. THANKS