Everything about The Codling Moth totally explained
The
codling moth (
Cydia pomonella) is a member of the
Lepidopteran family
Tortricidae. They are known as an
agricultural pest, their
larva being the common
apple worm or maggot. It is native to Europe and was introduced to North America, where it has become one of the regular pests of apple orchards. It is found almost worldwide. It also attacks
pears,
walnuts, and other tree fruits.
This larva is the famous "worm in the apple" of cartoon and vernacular fame; not related to the earthworm.
The codling moth is greyish with light grey and copper stripes on its wings, and has an average wingspan of 17 mm. The females lay eggs on fruit or leaves and the black-headed yellow larvae attack the fruit immediately upon hatching. Each larva burrows into the fruit, eats for around three weeks, then leaves the fruit to overwinter and
pupate elsewhere. Most nourishment is obtained by feeding on the proteinacous seeds.
The Codling Moth is
bivoltine in most regions of the USA - in the Pacific Northwest there's a partial third generation.
Control
Codling moth infestations are often managed with
pesticides. Successful synthesis of
codlemone, the codling moth female sex pheromone blend, has led to behaviorally based monitoring and management.
Pheromone traps are used to capture male moths for monitoring and setting
biofix, which is the time of first flight for codling moth. Biofix is used with weather data to run
degree day models (see below) which predict with excellent accuracy the phenology of the population in the field, thereby allowing growers to time their management actions to target codling moth when they're most susceptible. A
kairomone which is a feeding attractant can be used to capture males and females (DA lure).
Mating disruption can be used to effectively manage codling moth populations in many cases. Mating disruption involves the use of a pheromone impregnated release device, typically made of plastic or rubber. Dispensers are distributed throughout the orchard and emit female pheromone at a high, relatively constant rate. The mechanism by which mating disruption affects males is poorly understood, it may increase the time required for males to find females, thus reducing fecundity, or it may simply mask the position of females to searching males, reducing mating substantially. Codling moth isn't a great candidate for
biological pest control, as the larvae are well protected within the fruit for the majority of development. However, codling moth eggs are susceptible to
biological control by
Trichogramma wasps. The wasps deposit their eggs into codling moth eggs, and the developing wasp larvae consume the moth embryo inside. Another method for control and sampling, 'trunk banding', consists of wrapping a corrugated cardboard strip around the tree trunk. Larvae making their way back to the tree to pupate after the infested fruits are aborted will use bands as pupation sites. Bands may then be removed and burned.
Recent trials of non-toxic
kaolin clay-based sprays indicate that an effective alternative means of codling moth suppression may be on the horizon. Codling moth and other pests find leaves and fruit covered in kaolin clay unfit for laying eggs. Tiny particles of the clay tend to attach to their bodies, disturbing and repelling them. In addition, trees covered in kaolin clay can make them less recognizable as habitat to codling moths. Full coverage of trees is necessary in order to achieve effective suppression. If used only at the beginning of the fruit growing season, kaolin clay often comes off by itself due to wind and rain attrition, leaving fruit clean at harvest time.
The prime difficulty in dealing with codling moth infestations seems to lie with appropriate timing. The method of calculating 'degree-days' is often used by orchardists to approximate when a particular pest will reach a particular stage of development during a given season. Since stages of insect development are triggered by the accumulation of a certain amount of heat over time, this calculation involves careful tracking of changes in daily temperature. In the case of codling moth, pupating larvae emerging from bark and other overwintering spaces will migrate and burrow into apples soon after petal fall. For a given larva, this migration takes place within a mere two to three hours. Effective control using any method therefore depends crucially on identifying when decisive moments such as these occur.
Further Information
Get more info on 'Codling Moth'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://codling_moth.totallyexplained.com">Codling moth Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |