Peach Injurious Insects
A Lecture To ToT trainees ( FFS)
By Mr. Allah Dad Khan
Provincial Coordinator IPM KPK
MINFAL Pakistan
Symptoms Oriental fruit moth larva inside peach
Wilting shoot tips ("flagging") caused by insect feeding; insect frass may be visible around entry holes burrows in fruit which cause the fruit to be soft, mushy and discolored; adult insect is a small gray moth; larvae are initially white with a black head but turn pink with a brown head as they mature
Cause Insect Comments Orietal fruit moths overwinter as mature larvae
inside protective cocoons in protected areas of trees or in leaf debris on the ground; insect may undergo six or more generations per year
Management Management of the oriental fruit moth usually
involves the application of insecticides or the use of mating disruptants; commercial growers should monitor moth numbers using pheromone traps and apply insecticide if average number of moths exceeds 10 per trap; chemical sprays should not be applied within 14 days of harvest
Oriental fruit mothGrapholitha molesta
Flagging caused by oriental fruit moth strike
Oriental fruit moth larva and damge to shoot tip
Oriental fruit moth
Symptoms Damage to fruit caused by San Jose scale
Scale insects cause damage by feeding on twigs, branches and fruit on peach trees, injecting toxins into the plant as they do so; if the infestation is heavy, gumming may occur on the bark and twigs or entire branches can be killed; insects are flattened discs, or "scales" with no visible legs; scales produce a white waxy coating which eventually turns black (black cap stage)
Cause Insect Comments Scale insects overwinter in the black cap stage; winged
adult males mate with females which retain their eggs inside the body until they hatch
Management Populations are often kept in check by natural enemies,
including predacious beetles and some wasps - although broad-spectrum insecticides may result in outbreaks of scale by killing off populations of beneficial insects; peach trees can be sprayed with horticultural oils when dormant which effectively kill scales without damaging natural enemies
Scale insects (White peach scale, San Jose scale)Pseudaulacaspis pentagonaQuadraspidiotus perniciosus
White peach scale on peach branch
White peach scale infestation
Scale
Damage to fruit caused by San Jose scale
White peach scale infestation
Scale
Codling Moth (Cydia pomonella)
Codling moth (Order Lepidoptera, Family Tortricidae) is the most serious pest of apple and pear worldwide (Fig. 1). In most commercial fruit producing regions and home yards in Utah, fruit must be protected to harvest a crop. Insecticides are the main control tactic. There are new insecticides available, many of which are less toxic to humans and beneficial insects and mites than earlier insecticides. For commercial orchards with more than 10 acres of contiguous apple and pear plantings, pheromone-based mating disruption can greatly reduce codling moth populations to allow reduced insecticide use
(Fig. 1) Codling moth adult
(Fig. 2) Codling moth larva
Codling Moth
Symptoms (Fig. 1) Young peach twig borer larva on peach
Peach twig borer (Anarsia lineatella) is found worldwide wherever stone fruits are grown. In Utah, it is a significant pest on peach, nectarine, and apricot. There are typically three generations of peach twig borer in northern Utah (May-June, July, and August-September) and four or more in southern Utah. Young larvae (Fig. 1) that have overwintered emerge from protected shelters on limbs and twigs during bloom to petal-fall and burrow into developing shoots (Fig. 2). When populations are high, spring larval feeding can cause substantial damage to trees. The first adults are usually detected during April in southern Utah and May in northern Utah. Economic yield loss occurs during the summer when larvae of subsequent generations attack the fruit (Fig. 3). Insecticides are currently the most effective control tactic. Lower toxicity insecticides such as microbial products (Bacillus thuringiensis and spinosad) and insect growth regulators (methoxyfenozide, diflubenzuron, and others) can provide excellent control when timed with early larval feeding and egg hatch.
Peach Twig Borer
Fig. 1) Adult prionus root borer, female (left) with ovipositor extended, and male (right) with larger antennae for detecting female sex pheromone.
Prionus root borers belong to a family of beetles (Order Coleoptera) commonly known as long-horned beetles (Cerambycidae). The larvae are often referred to as round-headed borers because their body shape is cylindrical.
Several species in the Prionus genus are large, root-boring beetles, and they are widely distributed
Prionus Root Borer (Prionus californicus)
Larvae
(Fig. 2) Prionus larvae of various ages, ¾ - 4¼ inches long.