|Trees and their Management (IIRR, 1992, 195 p.)|
Carabao, Pico and Katchamitha (Indian) are the three commonly grown varieties. Carabao is grown commercially for export while Pico (for ripe fruit) and Katchamitha (for green fruit) are limited to backyard planting.
Grafted plants are best because they come true to type, grow smaller and produce fruits earlier than seedlings.
Carabao and Pico grow best in places with distinct dry season that lasts for five months or longer. Katchamitha is less selective of climatic type.
Preferred for planting are those with net to gently rolling slopes, although hilly lands can also be planted. The soil should be deep, fertile, well-drained and slightly acidic.
This is best done before the onset of the rainy season. Shrubs and trees should be cut down, preferably uprooted and the debris removed from the site. In flat to gently rolling lands, one deep plowing and two to three harrowings are adequate. In hilly areas, these operations are dispensed with.
In net to gently rolling lands, the recommended planting distance is from 10 m (100 trees per ha) to 15 m (44 trees per ha) depending on the fertility of the soil and the amount of rainfall. In hilly areas, planting distance is adjusted according to the contour of the land. Planting is best done at the onset of the rainy season.
The planting hole should be just large enough to accommodate the ball of soil of the planting material. After removing the plastic bag, set the plant at the center of the hole and fill up the extra space with the previously dug top soil.
TRAINING AND PRUNING
Allow the trees to grow upright for some time. When about 50 cm high, pinch the terminal bud to force lateral shoots to sprout. Allow the shoots to mature and again pinch the terminal bud on each shoot. Repeat this process until the end of the third year. Allow all shoots to mature and start forcing them to flower.
Once the trees are bearing, limit pruning to removing weak branches at the tree interior and those damaged by pests.
Water the trees right after planting and during period when rain falls irregularly. The first dry season after planting is the most critical stage. Water the trees regularly during this whole period. During the subsequent dry seasons, the trees will survive without irrigation although they will grow better and produce more and larger fruits if irrigated.
Soil and leaf analyses will aid the grower on the kind and amount of fertilizers to apply to the mango trees. In the absence of this information, apply 200-500 9 ammosul (or equivalent amount of urea) to each non-bearing tree (1-3 years old) at the onset and end of the rainy season. Shift to complete fertilizer (N-P-K) starting on the 4th year by applying 500 9 per tree twice a year. Increase the amount every year so that at the peak of fruiting (20-25 years old), each tree should get at least 5 kg per application.
Broadcast the fertilizer evenly or apply in several shallow holes beneath the tree canopy.
If organic fertilizers (e.g., compost, manure) are available, apply liberal amount to reduce the need for inorganic fertilizer.
CONTROL OF PESTS
Leaf hoppers and oriental fruit flies are the most serious insect pests. Control hoppers with carbaryl or malathion insecticide when the inflorescence starts to emerge. Repeat this three or more times at 7-10 days interval depending on the degree of infestation.
Control fruit flies using an attractant (e.g., methyl eugenol, powdered kalingag bark) treated with an insecticide.
Vapor heat treatment of fruits after harvest also effectively kills fruit fly eggs and larvae.
Anthracnose is the most serious disease and attacks the flowers, young leaves and young fruits. To control, spray the tree with benomyl (e.g., Benlate) or mancozeb (e.g., Dithane M-45) fungicide regularly from fruit set until a month before harvest.
Force mature trees to flower off-season by smudging or foliar spraying with potassium nitrate. Apply the latter at 12 percent dosage (10-20 g/li water). Commercial formulations in solution are applied at recommended dosages.
Trees can be forced to flower any month although the common practice is to time the application at the onset of the dry season in November. Even then, not all trees can be forced to flower at the same time because only those with 6-month-old shoots or older are responsive.
One spraying is enough and flowers appear after about two weeks. Trees that failed to flower or whose flowers were destroyed may be sprayed again.
To reduce mechanical injuries as well as pest damage, wrap the fruits individually about 55 days after flowerforcing using used newspapers.
Harvest fruits 110-120 days after flower-forcing or 82-88 days after full bloom.