How to Manage Pests

UC Pest Management Guidelines

DESCRIPTION OF THE PEST

The adult psyllid is a small insect (about 0.12 inches or 3 mm) that resembles a cicada. The adults have white or yellowish markings on the thorax, clear wings, and lines on the abdomen between segments. The tiny eggs are laid on stalks most commonly on the underside of leaves and along leaf margins and are best seen with the use of a hand lens. Initially white, they turn a pink color a few hours after they are laid.

Nymphs hatch from eggs in 4 to 15 days and have scalelike flattened, oval, yellowish green to orangish bodies with red eyes and three pairs of short legs. Older nymphs are greenish and fringed with hairs and have wing buds, which make them easy to distinguish from whitefly nymphs. They develop through five stages (instars) in 2 to 3 weeks before becoming winged adults. Nymphs feed most often on the underside of leaves.

Tomato psyllids have an extensive range of acceptable hosts, but solanaceous plants (tomatoes, potatoes, nightshades) are preferred.

DAMAGE

Psyllids have the potential to build large populations rapidly in peppers and produce large amounts of honeydew during their feeding. Significant crop losses can occur from the build up of honeydew and sooty mold on fruit. In coastal and San Joaquin Valley growing areas they are known to transmit Candidatus Liberibacter solanacearum, a pathogen of solanaceous crops.

MANAGEMENT

Management strategies are aimed at preventing the development of large populations in the field when fruit is present. An application of imidacloprid at planting is an important component of tomato psyllid management. Monitoring fields by inspecting plants as well as the use of sticky traps is essential to detecting a population before it can become established and will help determine the need for in-season foliar treatments.

Biological Control
While predators and parasites may attack psyllids, most parasites attack too late in the psyllid life cycle to stop crop loss and biological control does not appear to be a promising control strategy in the field.

Organically Acceptable Methods
Sprays of the Entrust formulation of spinosad are acceptable for use on organically certified produce.

Monitoring and Treatment Decisions
Monitor fields to determine the need for in-season treatments. Place yellow sticky cards at the field margins near the tops of plants as an indicator of psyllid movement into the field in areas where the psyllid occurs. If tomato psyllids are caught in the traps, examine foliage of pepper plants on the field margins for eggs and nymphs. If psyllids are present, a treatment may be warranted. Continue to treat if more than five psyllids are found per plant. Be sure to alternate treatment materials to help prevent the development of insecticide resistance.

If psyllids are present in the field, it is very important not to use carbamates (Sevin, Lannate, Vydate) for the control of other pests as these materials actually promote the development of psyllid populations.

Common name		Amount/Acre**	R.E.I.+	P.H.I.+
(trade name)			(hours)	(days)
When choosing a pesticide, consider information relating to impact on natural enemies and honey bees and environmental impact. Not all registered pesticides are listed. Always read label of product being used.
AT PLANTING
A.	IMIDACLOPRID
	(Admire Pro)	7–10.5 fl oz	12	21
	MODE OF ACTION GROUP NUMBER1: 4A
	COMMENTS: For a direct-seeded crop apply at planting as a side dress, through drip irrigation, or over the top as seedlings emerge. For transplanted peppers, apply at planting either through drip irrigation or as a soil application. Does not harm most beneficials. To reduce the potential for the development of resistance, avoid the use of neonicotinoids both as a soil and a foliar application on the same crop.
GROWING SEASON
A.	ABAMECTIN*
	(Agri-Mek) 0.15EC	8–16 fl oz	12	7
	MODE OF ACTION GROUP NUMBER1: 6
	COMMENTS: Do not apply at less than 7-day interval. Do not exceed 48 fl oz/acre/growing season. Do not apply in less than 20 gal water/acre. Do not make more than 2 sequential applications.
B.	PYRIPROXYFEN
	(Knack)	8–10 fl oz	12	14
	MODE OF ACTION GROUP NUMBER1: 7C
	COMMENTS: An insect growth regulator that is not harmful to most beneficials.
C.	SPIROTETRAMAT
	(Movento)	4–5 fl oz	24	1
	MODE OF ACTION GROUP NUMBER1: 23
	COMMENTS: Minimum interval between applications is 7 days and maximum allowed per season is 10 fl oz.
D.	SPIROMESIFEN
	(Oberon) 2SC	7–8.5 fl oz	12	7
	MODE OF ACTION GROUP NUMBER1: 23
	COMMENTS: Do not exceed three applications/crop or make applications at less than 7-day intervals.
E.	SPINOSAD
	(Entrust)#	1.25–2.5 oz	4	1
	(Success)	4–8 fl oz	4	1
	MODE OF ACTION GROUP NUMBER1: 5
	COMMENTS: Do not exceed 29 fl oz of Success or 9 oz of Entrust/acre/crop.
**	See label for dilution rates.
#	Acceptable for use on organically certified produce.
+	Restricted entry interval (R.E.I.) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Preharvest interval (P.H.I.) is the number of days from treatment to harvest. In some cases the REI exceeds the PHI. The longer of two intervals is the minimum time that must elapse before harvest.
1	Rotate chemicals with a different mode-of-action Group number, and do not use products with the same mode-of-action Group number more than twice per season to help prevent the development of resistance. For example, the organophosphates have a Group number of 1B; chemicals with a 1B Group number should be alternated with chemicals that have a Group number other than 1B. Mode of action Group numbers are assigned by IRAC (Insecticide Resistance Action Committee). For additional information, see their Web site at http://www.irac-online.org/.

PUBLICATION

UC IPM Pest Management Guidelines: Peppers
UC ANR Publication 3460
Insects and Mites
E. T. Natwick, UC Cooperative Extension Imperial County
J. T. Trumble, Entomology, UC Riverside
Acknowledgment for contributions to Insects and Mites:
W. J. Bentley, UC IPM Program, Kearney Agricultural Center, Parlier
R. L. Coviello, UC Cooperative Extension, Fresno County
C. G. Summers, Kearney Agricultural Center, Parlier
W. E. Chaney, UC Cooperative Extension, Monterey County
C. F. Fouche, UC Cooperative Extension, San Joaquin County

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