The fruits are sweet, having small seeds and are slow to ripenCUSTARD APPLE is a promising tree of commercial value grown mostly in dry tracts of India. The fruits are widely consumed in many parts of the country and the seeds are of insecticidal value.
Potent insecticideThe oil extracted from the seeds is used as a potent insecticide along with neem formulations. The leaf extract is used to repel honeybees while extracting honey from the beehives. It is called Sitapazham in Tamil, Sitaphal in Kannada and Telugu, and Sarifa in Hindi. The hardy fruit tree grows well in soils having a good drainage for water.
New varietyHeavy soils and waterlogged fields are not suitable for its cultivation. Researchers at the Indian Institute of Horticultural Research (IIHR), Bangalore have developed a new variety of custard apple called Arka Sahan. The fruits of this variety are sweet, having a few small seeds and are slow to ripen (6-7 days). The pulp is snow-white in colour and juicy with a mild aroma.
GraftingTraditionally propagated by seeds, this fruit tree can also be multiplied vegetatively by grafting, according to Dr. S.H. Jalikop, Principal Scientist, Division of Fruit Crops, Indian Institute of Horticultural Research, Bangalore. Pits of 60 cm x 60 cm size are dug and left open under the sun for a week. They are filled with topsoil mixed with 25-30 kg of well-decomposed farmyard manure. The seedlings should be transplanted 5 m x 5 m apart.
Irrigation scheduleAbout 400 seedlings are required for planting in a hectare. Watering is done in the initial phase of establishment, and being a drought-tolerant crop, it can remain green and healthy even during protracted dry spells. Irrigating plants at least during flowering and fruit development is essential. Fruit quality is superior in irrigated plants, with more edible pulp. Plants receiving regular water grow luxuriantly with each bearing. In regions having limited water, pitcher, trickle, or drip irrigation systems, help in judicious use of water.
Good growthRegular watering during dry periods, occasional hand digging of the basins to check weeds, keeping the soil loose, plant protection measures, manuring, removing of sprouts on stock, and building up of a good framework are necessary for aiding good growth of the trees. The crop is free from most pests and diseases. The only pest that attacks this crop is the mealy bug. Spraying suitable botanical insecticides is found effective in controlling it. The tree starts bearing fruits from the fourth year of planting, and the yield declines gradually after the thirteenth year.
Fruiting seasonIt yields fruits during August to October in south India and during September to November in the northern parts of the country. Selective and mild pruning of deadwood and very old branches should be carried out as and when required to avoid congestion and encourage well-spaced branching. "In Arka Sahan as in other custard apple types, a few flowers (of about 1-2 per cent) develop into fruits owing to male and female structures maturing at different times, besides limited insect and wind pollination. Hence the cropping potentiality will not be realized with only natural pollination. To supplement this, simple artificial hand pollination is recommended, " said Dr. Jalikop
Hand pollinationHand pollination is a simple and fast technique that results not only in good fruit set but also produces big size, attractive uniform shape fruits with no loss in edible attributes. Thus fruit yield can be significantly increased by artificial pollination. A tree of Arka Sahan can produce 40-45 kg fruits from the eighth year after planting. Hence in each tree about 150 flowers should be hand pollinated to achieve an expected yield of 25 tonnes per hectare. Fruits developed from hand pollination command a premium price in the market. As Arka Sahan is an inter-specific hybrid it should be propagated by grafting and not by seeds.
On an average, a well nurtured, eight-year-old tree will produce about 100 to 150 fruits, and a total yield of about 7 tonnes can be harvested from a hectare. The fruits are harvested manually when they are fully mature and still firm. About 5 to 6 pickings will be needed to harvest all fruits during a season. The fruits ripen in about three days after plucking. The medium sized fruits weigh 250-300 gm with sweet pulp and pleasant aroma and have about 60 to 80 seeds inside them. For more information readers can contact Dr. S.H. Jalikop, Principal Scientist, Division of Fruit Crops, Indian Institute of Horticultural Research, Hessaraghatta Lake Post, Bangalore 560089, email: firstname.lastname@example.org, mobile: 09449048722