Effects of predators on control of pear psylla
AuthorsHarold F. Madsen
Tim T. Y. Wong
Authors AffiliationsHarold F. Madsen is Associate Entomologist, Department of Entomology, University of California, Berkeley; Tim T. Y. Wong is Laboratory Technician II, Department of Entomology, University of California, Berkeley.
Hilgardia 18(2):2-4. DOI:10.3733/ca.v018n02p2. February 1964.
Studies have been conducted for the past two seasons on the action of predators against the pear psylla. Most of the work has been done at the University of California Deciduous Fruit Station, San Jose, on a block of pears that has been left untreated. The trees at this orchard had received all cultural requirements except the application of pesticides. The orchard suffered heavily from pear psylla attack from 1959 through 1961. In 1962 predators (anthocorid bugs and lacewings) brought the pear psylla population to a low level. The trees (Winter Nellis on Old Home-Farmingdale root-stock) responded by growing vigorously, whereas in previous seasons, growth had nearly ceased and the foliage was yellow and sparse. Studies were continued in 196S to determine if the predators would continue to regulate the pear psylla population.
Also in this issue:Effects of sulfur on five annual grassland species
A progress report: Redesigning pear trees for mechanical harvesting
Lygus bug control during flowering in dry lima beans
Phosphorus - deficiency - induced dormancy symptoms in alfalfa
Precision tillage for cotton beneficial on coarse-textured soils, but not on clay
Minimum tillage for cotton
Ventura county survey finds little avocado root rot
Soil moisture affects photosynthesis
Astringency of fruit and fruit products in relation to leucoanthocyanin content
Chemical fallow aids perennial grass establishment
Herbicidal properties of oils