Some useful products
Some Products safe to Trichogramma wasps
Various chemical insecticides are available that are relatively "safe" to Trichogramma wasps.
A number of biological insecticides are available for the control of caterpillars that are particularly soft on natural enemies:
Pheromone traps are available for Helicoverpa armigera and H. puntigera, lightbrown apple moth and codling moth. These may be useful especially early in the season.
The reliability of heliothis traps in sweet corn is still uncertain. Heliothis traps consist of a 3 litre plastic container half filled with water with entrance holes around the the top. The trap houses a pheromone bud which emanates the scent of the female moth. Males moths are attracted into the container and drown in the water. Moth numbers are counted and the trap cleaned once or twice per week.
It is difficult to provide guidelines for the interpretation of trap catches. Growers are best to install them on their properties and over time develop their own rating system.
An egg lay usually follows shortly after a trap catch. It can provide advance warning of a large egg lay. A large egg lay rarely follows a low trap catch but sometimes a large trap catch is not followed by a large egg lay.
Dunluce International Pty Ltd can be contacted on Phone/Fax 02 9983 1776 for details of your nearest supplier.
There are a number of formulations of B.t. available. The notes and diagram below summarises the action of the Abbott Dipel® product:
DiPel is composed of a spore and a crystal which provides 2 modes of action for controlling Heliothis - Gut Paralysis and Septicaemia. When DiPel is ingested by Heliothis the alkaline gut environment activates the crystal endotoxin causing perforation of the gut wall and a cessation of feeding. The second stage is when the spores leak into the blood through the perforated gut wall, germinating and beginning the reproductive phase. It takes 1-3 days for the larvae to die from septicaemia.
DiPel is very specific to Lepidopteran insects and has no effect on any beneficial insects or spiders.
Gemstar® - Contact the manufactures representative for details of current registrations.
The following is information provided by the Rhone-Poulenc to cotton growers:
GEMSTAR* a product of Rhone-Poulenc Rural Australia ACN 000 226 022
A liquid Concentrate Biological Insecticide for Control of Helicoverpa punctigera and Helicoverpa armigera.
Active ingredient: Polyhedral occlusion bodies (OBs) of the nuclear polyhedrosis virus of Helicoverpa zea 0.64%
> 2 billion OBs/mL
Inert ingredients 99.36%
Insect viruses (also called baculoviruses) are naturally occurring insect specific pathogens and have been part of the environment for millions of years. These baculoviruses play an important role in the natural control of insect populations and have no effect on other animal or plant life.
These nuclear polyhedrosis viruses are rod shaped, elongated particles enclosed in protein crystalline matrices which are occlusion bodies (OBs). Insects must consume the OBs from the surface of the leaf to become infected with the virus. The OBs are quickly dissolved within the midgut of the caterpillar, releasing the infectious virus particles. The virus penetrates the gut and moves into the insects body, sealing its fate. Within three or four days, the caterpillar becomes sluggish and feeding slows considerably. The internal organs start to disintegrate and caterpillars begin to die about five days after ingestion. Shortly after death, the body ruptures, releasing billions of new OBs that, under the right conditions, will infect other caterpillars.
GEMSTAR is a natural biological insecticide, which requires optimum conditions to achieve best results. Typically, GEMSTAR provides between 60 and 90% control of larvae. GEMSTAR does not control eggs. Although GEMSTAR can be used in alternation with synthetic insecticides its best fit is where integrated pest management principles have been adopted i.e. preservation of natural enemies such as predators ( e.g. Lady Beetles) and parasites (e.g. Microplitus and Ascovirus)
Optimum conditions for the performance of GEMSTAR:
USE PATTERN & BENEFITS
Insecticide resistance management - early season use of GEMSTAR will reduce selection pressure on conventional insecticides such as LARVIN hence delaying development of resistance.
In protected environments - where pests threaten crops growing near reservoirs, wildlife habitat and recreation areas.
In Ingard# cotton, GEMSTAR can provide control of larvae not controlled by Ingard cotton with no harm to beneficial insects.
In Integrated Pest Management programs. IPM programs focus on the management of insect pests by manipulating predator populations and the use of strategically applied insecticides. With its very narrow spectrum and hence its safety to beneficial insects GEMSTAR has a good fit in IPM programs.
DRAFT LABEL. The use pattern below is not currently registered. However a permit has been issued for this use. Refer to the permit and trial protocol before use of this product.
PestCropRate/ha: Helicoverpa armigera, Helicoverpa punctigera
Cotton Stage I up to flowering 500 mL. Cotton Stage II and III 500 mL + a synthetic pyrethroid at the recommended rate. Sorghum, chickpeas 375 mL
Timing of application:
All crops: - Apply at emergence of larvae. Gemstar is most effective on very small and small larvae i.e. up 13mm in length. Up to 7mm in length in cotton. Gemstar will at best provide between 60 to 90% control, so should only be used in crops where protection against damage is not of paramount concern.
Sorghum: apply 3 days after 50% of panicles have reached 100% flowering Cotton: If larvae numbers exceed 4/m Gemstar is unlikely to reduce the numbers below threshold.
Chickpeas: If larvae numbers exceed 6/m Gemstar is unlikely to reduce the numbers below threshold.
Gemstar is a biological insecticide hence its efficacy is dependent on environmental conditions, application and feeding behaviour of the pest. For this reason when environmental and crop microclimatic conditions are unfavourable for Gemstar, control of the pest may be below expectations.
The performance of Gemstar is enhanced by the presence of beneficial insects. Prior to Gemstar use avoid applying insecticides which might disrupt the beneficial population.
Gemstar needs to be ingested to be effective, so coverage of the target area, where the larvae are feeding, is essential.
As Gemstar is readily degraded in the presence of ultra violet light it should preferably be applied in the late afternoon or early evening. This will ensure that larvae feeding during the night will have a significant opportunity to ingest the product before it is degraded.
The product acts slowly and can take up to 8 days to kill larvae. Speed of kill and efficacy is dependent on climatic conditions. Warm conditions will favour the performance of Gemstar as the larvae will be feeding actively and moving around. Daytime temperatures of 25ûC to 35ûC are ideal for Gemstar performance.
Gemstar should always be sprayed with a non-ionic surfactant at a rate of 0.01% of spray volume i.e. 25mL of X77 per 100L of spray mixture.
Apply in sufficient water and using application parameters (nozzles, swath width, pressure, boom height, speed, etc) to ensure thorough coverage of the target area.
The addition of skim milk powder at a rate of 1.0 Kg/ha may enhance the performance of Gemstar in chickpeas.
HANDLING & SAFETY
In case of contact with eyes, flush with plenty of water for at least 15 minutes. If on skin, wash thoroughly with soap and water. If inhaled, remove victim to fresh air. Apply respiration if indicated. Get medical attention if irritation persists. Keep out of reach of children
It is recommended that GEMSTAR be stored at less than 20û C. The shelf life at this temperature is about 2 months. For longer-term storage, keep refrigerated at 4û C. Storage over 35û C may inactivate GEMSTAR in less than 2 months.