Cultivation Practice of Avocado in Nepal.pptx
- 2. Introduction • Nepali Name: Ghiu fal (butter fruit) • S.N: - Persea americana • Family - Lauraceae • Avocado is a perennial plant • It is a hardy plant.
- 3. • Avocado is medium to large ever green plant • Known as a 'poor man’s butter’ to the King of Fruits • Most varieties of avocado are oval or round shaped with thick, rough green skin. • The avocado is native to Mexico and Central America • Avocado or alligator pear also refers to the fruit, botanically a large berry that contains a single seed.
- 4. Uses of Avocado • Health benefits – lower cholesterol levels – seeds, leaves, and bark are used for dysentery and diarrhea. – promote hair growth – relieve toothache. – Use for skin care • It contains Omega 3 fatty acid • Use as food item • Beverages
- 8. Climatic Condition • Grown only in subtropical or tropical climates as well as warm-temperate climate • Altitude: 400m-1300m • Optimum Temperatures: 14-280C • Minimum survival temperature is about - 4 °C • Hot, dry conditions could result in low yields because of fruit and flower drop • A high humidity is desirable, because it decreases stress conditions • Annual Rainfall: 1800 mm is desirable
- 9. Soil Condition • Need well-aerated and loose soil • Deep, fertile loamy soil with good drainage is best Avocado trees tolerate both acidic and alkaline soils • pH range should be 4- 7 • Compacted soils will affect root spread • Refers slightly dry condition
- 10. Morphology • Trees to 30m tall • Leaves – Narrowly to broadly elliptic – Leaf blades 10-30cm long – 3-19cm width • Flowers – 3-6mm long – Yellowish green color – Determinate and indeterminate type
- 14. • Root system – Shallow root system • Fruit – pear-shaped, – often more or less necked – oval or nearly round – yellow-green, deep-green or very dark-green, reddish-purple, or so dark a purple as to appear almost black, and is sometimes speckled with tiny yellow dots, – lossy or leathery skin
- 16. Major Varieties grown in Nepal  Hass  Fuerte  Reed  Topatopa  Ettinger
- 17. Reed Topatopa
- 18. Hass Ettinger
- 19. Pollock Simmods
- 22. GROWTH STAGES
- 23. Bud Development
- 24. Flowering • Avocado flowers carry both male and female reproductive organs. • Each flower opens twice over a two-day period. • The first day as a female and the second day as a male. • Air temperature regulates the opening and closing of flowers
- 25. Flower Opening and Pollination •Type of Flowers: Avocado trees have a unique flowering behavior known as "dichogamy," which involves two types of flowers: Type A and Type B. • Type A: Opens as female in the morning, closes, and reopens as male in the afternoon of the following day. • Type B: Opens as female in the afternoon, closes, and reopens as male the following morning. •Pollination: Cross-pollination between Type A and Type B flowers, often assisted by bees and other insects, increases fruit set.
- 26. Flowering and pollination • A mature avocado tree may produce in excess of a million flowers during the flowering period, most of which fall without producing fruit. • The purpose behind the mass flowering is to encourage visits by pollen vectors. • The avocado has a ‘complete’ flower, but with an unusual behaviour known as ‘Protogynous dichogamy’. • The avocado flower has both functional male and female organs in the one flower, but opens and closes twice over a two-day period — the first day as functionally female and the next as functionally male • Each opening stage only lasts about half a day.
- 27. Figure 1:Hass avocado flower during the functionally female stage, the first opening stage
- 28. Figure 2: Hass avocado flower during functionally male stage, after dehiscence, the second opening stage
- 29. • In general, on a single tree all the open flowers will be synchronised. • That means they will be all functionally male or all functionally female. • The avocado pollen of one tree is compatible with itself and quite capable of pollinating its own flowers — known as self-pollination. • The unusual flowering behaviour is to reduce the likelihood of this occurring — by minimising the amount of own- pollen about when female stages are receptive. • To further maximise the likelihood of cross-pollination some trees will open first in the morning as functionally female, close and then reopen the next afternoon as functionally male (type A flowering sequence).
- 30. • Other trees open first in the afternoon as functionally female, close and then reopen the next morning as functionally male (type B flowering sequence). • The timing of these stages determines the classification of varieties into either type A or B flowering. • We can see the table given below to know the opening sequence of type A and B flowering varieties and how this sequence promotes cross-pollination. • This is an evolutionary development to increase genetic diversity. Flower type Day 1 Morning Day 1 afternoon Day 2 Morning Day 2 afternoon A Female Closed Closed Male B Closed Female Male Closed
- 31. Flowering classification of common Avocado varieties Flower A type Flower B Type Hass Ettinger Reed Fuertee Hazzard Lianos Hass Lamb Hass Nobel
- 32. Three requirements for a successful fruit set 1. An overlapping of the flowering stages 2. Significant insect activity, including bees 3. Temperature is somewhat low
- 33. • The avocado exhibits a type of flowering behavior known as "synchronous dichogamy". • An individual flower will be open for 2 days, however the timing of the male and female phases are distinct. • When the flower first opens it is in the female phase and the stigma is receptive to pollen. • At the end of the female phase, which lasts 2 to 4 hours, the flower will close. • On the second day the same flower re-opens in the male phase and sheds its pollen.
- 35. • The avocado is also unusual in that the timing of the male and female phases differs among varieties. • There are two flowering types, referred to as "A" and "B" flower types. • "A" varieties open as female on the morning of the first day. • The flower closes in late morning or early afternoon. • The flower will remain closed until the afternoon of the second day when it opens as male. • "B" varieties open as female on the afternoon of the first day, close in late afternoon and re-open in the male phase the following morning.
- 36. • "A" varieties open as female on the morning of the first day. • The flower closes in late morning or early afternoon. • The flower will remain closed until the afternoon of the second day when it opens as male. • "B" varieties open as female on the afternoon of the first day, close in late afternoon and re-open in the male phase the following morning. • Since there are hundreds of flowers on an avocado tree at any one time. • The arrows denote the movement of pollen between the complementary flower types.
- 39. Bee pollinating the flowers Flowering with new buds
- 40. PRODUCTION OF PLANTING MATERIAL • Nursery management – Poly bag nurseries are prominent – Need proper drainage – Seed should be treated with hot water for 30 min – Apply fungicides and gypsum
- 41. Propagation • Sexual • Asexual or vegetative
- 42. Vegetative propagation • Grafting is prominent • Stem or branch may not be thicker than 2 cm diameter • Remove the top and bottom part of the branch • Two types of rootstock can be used – the cultivar and the seedling rootstock • cultivar rootstock is produced by vegetative methods, Seedling rootstocks grow from seed
- 45. • Land preparation – Dig holes large enough to take the root system comfortably – Do not place fertilizers in the planting hole – Half fill the hole with soil and Fill the hole with water
- 46. • Planting • Spacing varies among varieties  Seedling tree: 8-10m×8-10m  Grafted tree: 4-5m×4-5m  Optimum spacing for grafted tree:3-6m×3-6m Time of planting:  Best during rainy season  If irrigation is available can also be grown in Feb- March
- 47. Management practices • Mulching – Mulch provides organic matter, a valuable source of tree nutrients and food for beneficial soil microorganisms
- 49. • Tree training and pruning – Little pruning is required – regulate tree canopy size – tree removal • When yield decline immediately follows the removal of productive trees
- 50. • Selective limb removal – Limbs that are low, overlapping or growing up the centre of the tree – exposed limbs with white plastic paint • Stag horning – pruning a tree above the graft
- 51. Fertilizer management  Depends on soil fertility status, type of soil etc.  Usually fertilizer is applied after harvesting during hoeing.  FYM:25-50 kg  NPK: 250:125:125 g/tree/year
- 52. • Irrigation management – 1800 mm per year rainfall – Avocados are very sensitive to moisture stress, especially during • flowering • fruit set • fruit development – Irrigation systems should be designed depends on • number of trees per hectare • soil texture and depth • weather conditions • trees’ growth cycle
- 53. – In orchard's basically drip irrigation techniques – Water stress can cause symptoms including; • fruit drop • ring-necking • skin cracking • salt burn • In young trees, vegetative growth is reduced
- 54. Pest and Disease Management • Common pests – avocado leaf roller – Avocado thrips – Persea mites
- 56. Pests • Avocado thrips - Scirtothrips perseae – Symptoms • leathery patches and spread across fruit • adult insect is orange-yellow in color with distinct brown bands – Management • organic mulch about 6 inches • if insecticides are to be applied
- 58. • Diseases – Anthracnose – Scab – Stem-end rot – Phytophthora root rot – Black streak – Bacterial soft rot – Sun blotch – leaf spot
- 59. Anthracnose Scab
- 60. Diseases • Scab - Sphaceloma perseae – Symptoms • Oval or irregular brown or purple spots on fruit with rough texture – Management • Plant tolerant varieties; spray with copper containing fungicides
- 61. Harvesting • Handle fruit carefully during harvesting • Fruit should be cut off • Healthy fruit should be carried in canvas picking bags • Harvested fruit should be removed as soon as possible • place it in cold storage
- 65. Thank you