Suzanne W. T. Batra

Biological control in agroecosystems.

Living organisms are used as biological pest control agents in (i) classical biological control, primarily for permanent control of introduced perennial weed pests or introduced pests of perennial crops; (ii) augmentative biological control, for temporary control of native or introduced pests of annual crops grown in monoculture; and (iii) conservative or natural control, in which the agroecosystem is managed to maximize the effect of native or introduced biological control agents. The effectiveness of biological control can be improved if it is based on adequate ecological information and theory, and if it is integrated with other pest management practices.

Natural Polyesters: Dufour's Gland Macrocyclic Lactones Form Brood Cell Laminesters in Colletes Bees

Bees in the genus Colletes make their brood cells in the ground and coat them with a highly resistant, waterproof, transparent membrane. This membrane is a polyester constructed mainly from 18-hydroxyoctadecanoic acid and 20-hydroxy-eicosanoic acid, which are stored as their corresponding lactones in the Dufours gland of the bee. When lining the cells, the bee secretes its glandular content, and the membrane is apparently a product of polycondensation reaction of its contents. This appears to be the first report of a naturally occurring linear polyester. The term laminester (lamina ≃ layer + ester) for this class of compounds is proposed.

Floral Mimicry Induced by Mummy-Berry Fungus Exploits Host's Pollinators as Vectors

Leaves and shoots of blueberries(Vaccinium spp.) and huckleberries (Gaylussacia sp.) when infected by ascospores of Monilinia spp. become ultraviolet-reflective and fragrant and secrete sugars at their lesions. Insects that normally pollinate these hosts are attracted to the discolored leaves, ingest the sugars, and transmit conidia to their flowers, resulting in sclerotia (mummy-berry) formation.

Anthophora bees: unusual glycerides from maternal Dufour's glands serve as larval food and cell lining.

The Dufours gland of Anthophora abrupta, a solitary bee, secretes a complex mixture of liquid triglycerides containing one long-chain and two shortchain fatty acids. This is applied inside the earthen brood cells and added to the provision, where it is converted, perhaps by enzymes from the bees saliva or gut, to solid diglycerides that are later eaten by the bee larvae. This use of Dufours gland secretion as food and its nutritive function are reminiscent of the royal jelly secreted by honey bees.

Chemistry of the mandibular gland secretion of the Indian beePithitis smaragdula

The mandibular glands of the stem-nesting Indian beePithitis smaragdula contain a mixture of salicylaldehyde, citronellyl acetate, geranyl acetate, pentadecane, heptadecane, ethyl tetradecanoate, and ethyl hexadecanoate. Salicylaldehyde is reported for the first time from a hymenopterous source. The secretion, emitted when the bee is disturbed, is rubbed with the legs over the bees body and the disturbing object. The reactivity of some of the components in combination with the bees behavior make the glandular exudate an effective defensive secretion.

Chemistry of the cephalic secretions of eumenid wasps

Abstract 1. 1. The chemistry of the cephalic secretion of five species of eumenid wasps in the genera Monobia, Ancistrocerus, Stenodynerus and Pseudodynerus has been investigated. 2. 2. Several alkylpyrazines were identified in nearly all species except Monobia , in which diethyl disulphide was the major constituent.