In Apple, pears & cherry trees there are more than 38 major species of insects/ pest and mites capable of harming and damaging the fruit tree, from the shoots to roots. Some major pests, most common in Himachal Pradesh are given here with specific information.
CODLING MOTH (CYDIA POMONELLA)
Codling moth is the cause of what is often referred to as “maggoty apples”. The caterpillars of this pest can damage a high proportion of the fruits on apple trees and later on can damage the shoots of tree, results into high damage to the tree. The adult female moth lay eggs on branches, leaves and developing fruits. The larva of the pest enters into fruit from the surface and tunnels down to the core. Excessive damage is caused in the core region. The damaged fruit drops off prematurely; this starts happens in the month of mid may or starting of June and can continue till harvest.
The caterpillar’s exit hole is often visible in the side of the ripe fruit or at the ‘eye’ end (opposite side) When the fruit is cut open, the tunnel and feeding damage inside the core can be seen, with the caterpillar’s excrement.
The Measures strategy includes mass pheromone trapping, collection and destruction of over wintered cocoons during March-May and deep burying of fallen fruits during June-July. This is a microscopic worm-like creature that enters the bodies of caterpillars and infects them with a fatal bacterial disease.
Codling moth caterpillars can only be Measures led on apple and pear with insecticides before they enter the fruits On trees small enough to be sprayed, the newly-hatched caterpillars can be killed by using deltamethrin ,2 sprays of Phosphamidon (0.04%) in June-July at an interval of 2-3 weeks is effective in Measure sling the pest.
Use one of these sprays in about the third week of June, with a second application about three weeks later, if damage is heavy. In some years, egg hatching may be earlier or later, due to the weather conditions.
WINTER MOTH CATERPILLAR
Winter moth caterpillars are responsible for eating holes in the leaves of apple trees during summers. Winter moth caterpillars eat holes in the leaves; blossom and developing fruit lets of apple, pears and cherries trees. Severe attacks can weaken plants. Extensive damage to fruit trees can affect crop yields and quality. Wingless female winter moths emerge from pupae in the soil during October to February and crawl up trunks to lay eggs on the branches. Eggs hatch at bud burst and the pale green lopper-type caterpillars emerge and start feeding. The caterpillars are about 1in long and complete their feeding by early June. They then go down into the soil where they pupate. Trees are largely defoliated during the spring by the caterpillars of winter moth and other species. Such trees will survive and produce more leaves during the summer.
Attacks by winter moth caterpillars are usually first noticed in spring when emerging leaves are loosely bound together with silk threads and eaten.
The damage is particularly noticeable in mid-summer when the leaves are fully expanded and the small holes made during the spring have enlarged due to leaf growth.
Blossom and developing fruit lets can also be damaged. Early damage on apple fruit lets causes a deep cleft in the side of the fruits to develop by the time they have reached full size in late summer.
Egg laying can be reduced by placing a sticky grease band around the trunk and tree stake in late October to intercept the females. Many birds, especially tits, feed their chicks with large numbers of winter moth caterpillars during the spring.
Shortly after bud burst – but not during flowering – apples, pears trees can be sprayed with deltamethrin. An organic alternative is pyrethrum to Measures the young caterpillars.
APPLE CLEARWING MOTH (SYNANTHEDON MYOPAEFORMIS)
This is one of the most important pests in apple it attacks in the cracks or the cuts if it is not smooth during pruning or at the wound of tree if not properly covered. The larvae make tunnels in the bark of old trees leading to peeling of bark. This makes the barks prone to infection by other decaying organisms.
Winter spraying (when the larvae start feeding) as well as summer spraying (when the adults appear) is recommended to Measures the pest. Immediately on appearance of the larvae Chlorpyrifos (0.15%) is sprayed 3 times at an interval of 20 days for best results.
WOOLLY APPLE APHID (ERIOSOMA LANIGERUM)
Woolly apple aphid is a serious pest attacking apples, and it migrates from root to shoot and vice versa throughout the year and can stay active in mud for long if climate is dry. It is a small, brown and grayish purple with white powered like coating sucking aphid, which attacks bark and roots forming galls on roots, stem and shoot resulting swelling in shoots branches and even roots.
Resistant rootstocks should preferably be used for grafting the desired cultivar. Soil application of Phorate or Carbofuran granules during May and October/November checks incidence and spread of the pest. Spraying with Chlorpyriphos (0.02%) or Fenetrothion (0.05%) twice in May and June Measuress the pest effectively.
BLOSSOM THRIPS (TAENIOTHRIPS SPP. THRIPS FLAVUS, THRIPS CARTHAMI, HAPLOTHRIPS CEYLONICUS)
Thrips attack is favored by hot-and dry weather conditions. They cause extensive damage to the flowers. The flowers attacked by the thrips show withering symptoms resulting in poor fruit set or pre-mature fall in the early stages of development. Heavily infested bloom produces distorted flowers that open on one side.
Bio-Measures agents like Chrysopa sp. and ladybird beetle (Coccinella septumpunctata) act as predators of thrips. Foliar application of Chlorpyriphos (0.04%) or Fenetrothion (0.05%) at pin bud stage is recommended for Measures of the pest.
RED SPIDER MITES (PANOYCHUS ULMI)
elative humidity favors mite multiplication. Different stages of mite are found in colonies covered by white-silky webs on lower surface of leaves. The adult lay reddish eggs underneath the leaves and on the spurs. Nymphs and adults suck cell sap and bronze patches appear on leaves. Affected leaves become mottled, turn brown and fall.
Predators like coccinellids, predatory mite and anthocorid bug help to reduce the population of mites. Spraying with Dicofol (0.05%) followed by Malathion (0.05%) effectively reduced the mite infestation.
SAN JOSE SCALE (QUADRASPIDIOTUS PERNICIOSUS)
The ash-colored scales feed on the bark of trunks and branches by sucking sap of the tree. The affected bark surface shows grayish specks. The pest also infects the fruits leading to the formation reddish spots.
Application of 2% Misible oil (6-8 liters/tree) to the dormant trees in winter followed by spraying with Diazinon (0.04%) during February-March Measuress the pest.
ROOT BORER (DORYSTHENES HUGELLI)
The root borer is a very destructive pest in sandy loam soils and is very difficult to trap and also very difficult to kill by insectides. The shining chestnut red beetles lay eggs in the soil during July-August. The grubs feed exclusively on the thick roots and are as long as 3 inches. The damage symptoms are often observed when substantial loss has already occurred.
Planting apple orchards on dry and sandy soils should be avoided because it is very difficult to maintain orchards on such soil with root borer. The adults should be trapped and killed in the month of September. Drenching the basins of the plants with Chlorpyriphos (0.04%)or dusting with Folidol dust (25 kg/ha) in September effectively Measures the pests.