Important Points

• It is known as the “Queen of Fruits”.
• It reached India in 1548.
• Pineapple is a non-climacteric fruit.
• Pineapple is a CAM, monocarpic, herbaceous plant.
• Etheral (ethephon) is used for flowering in pineapple.
• The average sugar content in pineapple is 10-12%.
• The citric acid content in pineapple is 0.6 – 0.8%.
• The largest area under pineapple is in Assam, and West Bengal is the largest producer.
• For subtropical and mild humid climate, a plant density of 63,400 plants/ha (22.5 × 60 × 75 cm³) is ideal.
• For tropical climate, 53,300 plants/ha (25 × 60 × 90 cm³) is ideal.
• Pineapple is a short-day plant.
• Gametophytic self-incompatibility is present in pineapple.
• Earthing up is an essential process in pineapple cultivation.
• NAA and NAA-based compounds – Planofix and Celemone @ 10-20 ppm – induce flowering in pineapple, but are less effective. Hence, etheral is used.
• Fruits ripening in winter are acidic.
• Aluminium sulphate – Best nitrogen fertilizer for pineapple.
• Multiple-crown disorder is found in cayenne group (Kew).
• Pineapple does not contain starch.
• Bearing in pineapple occurs on old-season growth at the terminal.
• Sugar Loaf – Sweetest and best-flavoured fruit.
• Flower bud differentiation occurs in pineapple at the 40-leaf stage.
• The fruit contains a special enzyme called ‘Bromelin’ which digests proteins.
• The name pineapple is derived from Spanish name ‘Pina’, given to the plant based on the appearance of its fruits, which resemble a pine cone. The name ‘ananas‘, which later became the generic name, is derived from Tupi Indian name ‘nana‘. In Gurani language, ‘a’ means fruit and nana means ‘excelling’. The generic name, ‘Ananas’, thus stands for the excellent edible quality of this fruit.

Climate: It is a tropical fruit. It grows well in a mild tropical climate. The optimum temperature for it is 21-23°C. At lower temperatures, there is no differentiation of the flower bud. It can be grown up to an altitude of 1100 m above sea level, provided they are frost-free. It requires an optimum rainfall of 150 cm, which is well distributed.

Soil: Pineapple can be grown in any type of soil (except heavy clay soil). However, sandy loam, laterite and slightly acidic soil with pH 5.5 to 6.0 are suitable for cultivating the crop. The soil should have low calcium content.

Varieties: There are many varieties of pineapple, which are divided into three groups according to the classification of Hume and Muller (1904). These are Cayenne, Queen and Spanish.

1. Kew- major commercial variety, especially valuable for canning, late ripening variety.
2. Giant Kew
3. Charlotte Rothschild
4. Queen- grown on hills, early variety, best desert variety.
5. Mauritius- mid-season variety of the Queen group, grown mainly in Kerala.
6. Jaldhup (distinct alcoholic flavour) and Lakhat: both fall under the Queen group
7. Cayenne- triploid variety- grown commercially in the Philippines. (dual purpose of fresh fruit and canning)
8. Carbenzona triploid variety

Propagation: Pineapple is propagated mainly by vegetative methods. It can be propagated from shoot suckers, ground suckers, slips, crown and stem bits and divided crowns.

However, suckers and slips are generally preferred for planting as they flower earlier than crowns. Propagation by crowns is very limited. Use of stumps or discs for planting is very rare in India.

Suckers: Suckers are shoots arising from the leaf axils on the main stem below the fruit or from the base of the plant near the ground. Suckers are better for planting, as the plants give first crop in 14-18 months earlier than slips.

Slips: The slips are the shoots borne on fruiting stem i.e. shoots arising from immediately below the fruit. Plants from slips give larger-sized fruits, though production is late (20-22 months). Slips are generally used for planting in varieties with weak suckers, such as Giant Kew and Kew.

Crown: Crowns in the Kew variety are often used as propagation material due to their habit of producing shy suckers. These are late fruit-bearing plants and take about 20-24 months.

Stumps: Stumps are the stock of fruits. They are also sometimes used to meet the shortage of planting material. Stumps are cut into pieces called discs and are first planted in furrows and allowed to germinate. Later, new shoots are separated and planted. This should be avoided as it produces irregularly shaped plants and low-yielding plants.

Land Preparation – The land selected for planting should be well prepared by ploughing. If the land is uneven, then terrace cultivation should be done. In the last stage of ploughing or digging, add FYM or compost. After levelling, the land is prepared for planting suckers in trenches and mounds. For a double row planting system, two shallow furrows, approximately 10-15 cm deep, should be dug. Suckers of uniform size (400-450 g) should be selected for planting, as these give the best yield as compared to suckers of bigger or smaller size. Planting material should be collected from high-yielding, well-managed farms which are free from pests and diseases.

Preparation of planting material- At the time of planting, some of the basal scale leaves should be removed from the suckers to encourage root formation and penetration into the soil. Before planting, the suckers should be dried for one or two days by spreading them upside down. Fresh roots should not be planted in moist soil; otherwise, they rot. To prevent mealybugs and heart rot, the roots should be dipped in Bordeaux mixture (1%) or Dithane Z-78 (0.3%) and Difolton (0.2%).

Planting Methods: The popular method of planting pineapple is the double row system. The distance between two rows is 60 cm, and the plants in each row are planted at a distance of 45 cm such that no two plants are exactly opposite to each other. The distance between the double rows is 1.5 to 2.0 m. In this method, 15,000 to 20,000 suckers can be planted per hectare. When more than two ratoon crops are to be grown, the above method can be adopted. Otherwise, a lesser distance can be chosen. In this method, quicker and higher yield is obtained from a unit area. In this method, a distance of 25X60X105 cm or 25X60X90 cm is adopted. This can plant 49,000 to 53,000 suckers per hectare.

Planting time: Generally, planting can be done during the rainy season, avoiding heavy rains. July and August are the best months. However, where irrigation facilities are available, planting can be done throughout the year.

Interculture: After planting, light hoeing should be done wherever weeds are visible. Mulching with dry grasses, straw, sawdust, coir, rice husk, etc. will also help to suppress weed growth, retain moisture and maintain the humus status of the soil. To obtain good fruit size and uniform cylindrical shape, fruit crowns can be removed with a sharp knife when they are 5-10 cm long. In hot weather, fruits can be covered with leaves, dry grasses, straw, banana leaves or paper wrap to protect them from sunlight.

Fertilizer: After planting, apply 35 g of urea, 13 g of superphosphate and 6-8 g of MOP per plant two to three times.

• FYM – 20-25 tonnes
• Nitrogen – 350 kg/ha
• P₂O₅ – 130 kg/ha
• K₂O – 40 kg/ha

FYM and P₂O₅ can be applied as base dressing at the time of last ploughing or digging.

Nitrogen and K₂O should be applied in three divided doses, i.e., on 60th, 150th and 240th day of planting. Nitrogen can be given in the form of ammonium sulphate. Immediately after applying manure, the crop should be irrigated and then earthing up should be done to provide better support to the plant.

Irrigation: Though pineapple is a drought-resistant crop, to get high yields, it should be irrigated, at least during the dry periods. Irrigations are given for getting better-sized fruits. Therefore, 4-5 irrigations in hot months at an interval of 15-20 days will ensure a good crop.

Flowering: One of the major constraints in the successful cultivation of pineapple is its irregular flowering behaviour. Even after 15 to 18 months of growth under ideal management, less than 40 to 50% of the plants flower normally, leading to overlapping in operations and irregular supply of fruits to canning factories. Therefore, it is very important to regulate flowering for better profits and regular supply to canning factories. Regulating flowering will also reduce labour requirements. To obtain uniform flowering in pineapple, NAA in the form of 10-20 ppm ‘Planofix’ (1 ml Planofix in 9 litres of water) or 10 ppm ethephon (Ethrel) + 2% urea + 0.045% sodium carbonate is used.

Plants usually flower 12 months after planting, from February to April. Fruits take about 135 to 165 days to ripen. Depending on the variety, fruits ripen from June to September.

Harvesting: The fruit is ready to be harvested when at least 2 or 3 rows of eyes at the base turn yellow. However, for distant markets, ripe fruits should be harvested. Harvesting is done by cutting the fruit stem a few centimeters below the base of the fruit with a long, sharp knife. The fruit, including the crown, can be stored without damage for 3-4 days after harvesting.

Yield: The yield per hectare is 40-60 tonnes, depending upon the variety.

Ratoon crop: Ratoon crop is common in pineapple. After harvesting the first crop, all the branches on the mother plant are removed except one. The plants are then fertilized, irrigated and earthed up so that the plants can take root well for the ratoon crop. The crop is maintained for four or five years and then removed.

Pest Control

The pineapple is generally free of pests, except for infestations by mealy bugs and scale insects.

Disease Control

No diseases affect the pineapple except stem rot. Control measures include good drainage and dipping the roots in a Bordeaux mixture before planting.

Physiological Disorders

Multiple Crown

• Multiple crowns in pineapple is a physiological disorder in which a single fruit develops two or more leafy crowns instead of the normal single crown.
• The top of the fruit is often flat and broad.
• Such fruits may be corky and have a bland taste.

Causes

Damage to the growing point (meristem): This may be due to mechanical injury, insect damage, or hormonal imbalances within the plant.

Environmental factors: Extreme temperature fluctuations or irregular water supply may also trigger this abnormality.

Genetics: It is believed to be a genetic trait, found mostly in the Cayenne group, including the ‘Kew’ variety.

Management
Avoid ratoon cropping: Ratooning (taking a second crop from the stump of a plant) can increase the likelihood of multiple crown formation.
Proper cultural practices: Using proper planting and spacing along with balanced nutrient management and consistent irrigation can help reduce this and other abnormalities.