Effect of trap position, habitat, and height on the capture of pepper maggot flies (Diptera: Tephritidae).

Trapping results indicate that pepper maggot, Zonosemata electa (Say), flies occupy tree canopies adjacent to fields when not on host plants. Several in- and near-field trap positions were used to find a reliable monitoring system for adult pepper maggots. Traps baited with liquid ammonium hydroxide (Stills-style trap), hung in the canopy of trees on the edges of pepper fields, caught significantly more Z. electa flies than when positioned lower along the treeline or in the field. In a second experiment, significantly more pepper maggot flies were captured in sugar maples compared with choke cherry trees, which indicates a pest preference for certain nonhost habitats. The lowest trap height tested (2.1 m) failed to capture Z. electa flies in either tree species when the pest population level was low. These studies demonstrated that pepper maggot flies can be reliably detected with Stills-style traps positioned at approximately 6.4 m height within the canopy of sugar maple trees adjacent to pepper fields. Fruit oviposition scars also are useful site-specific indicators of pepper maggot presence/absence and may aid in determining if insecticide applications are necessary and in timing sprays.

The photobiological activity of 5-geranoxypsoralen and its photoproducts.

5-geranoxypsoralen (Bergamottin) does not photosensitize bacteria or a bacterial virus. It does, however, photosensitize mammalian cells in tissue culture. Irradiation with either black light (300-400 nm) or fluorescent ceiling lights produced at least four photobiologically active degradation products, the chemical nature of which still remains to be elucidated. Prolonged exposure to black light resulted in the formation of inactive molecule(s).

Follicular growth and maturation in the domestic hen (Gallus domesticus).

The rate of follicular development in hens was assessed by measuring the increase in the diameter of follicles during 120 h before ovulation and the mass of follicles during 48 h before ovulation. The rate of follicular maturation was estimated by the ovulatory response of follicles to an injection of GnRH and the ability of follicles to produce progesterone in response to an injection of LH. Follicular diameter and follicular mass increased until ovulation, indicating that the follicle continues to sequester yolk material until ovulation occurs. The ovulatory response to GnRH and the production of progesterone in response to LH were negligible until 10 h after ovulation and then both aspects of follicular competence began to be functional. It was concluded that the size of the hen's ovum is not a primary factor regulating ovulability; rather, the acquisition of the ability to ovulate spontaneously is associated with the ability to produce progesterone in response to an LH stimulus. The ability to ovulate in response to GnRH was acquired more quickly in hens laying long sequences than in hens laying short sequences, indicating that the ovulatory response of the follicle can be used to assess the reproductive potential of laying hens.