NOTES ON THE SPATIAL PATTERN OF HYPERA POSTICA (COLEOPTERA: CURCULIONIDAE) ON ALFALFA

Abstract

The Poisson and the negative binomial series, Taylor’s power law, and Morisita’s Iδ-index were used to interpret the dispersion of field counts of the immature stages of Hypera postica (Gyll.) on alfalfa. The data conformed consistently to an overdispersed distribution. Transformations are offered for stabilizing the variance of field counts.

POPULATION ASSESSMENT DURING THE LARVAL STAGE OF THE ALFALFA WEEVIL, HYPERA POSTICA (COLEOPTERA: CURCULIONIDAE)

“…These data are in substantial agreement with the prelimioary report of Miller et al (1972) which pertained to populations of lower density and to 12-stem units of foliage. However, their values for k c varied considerably between instars and were generally smaller than those reported here.…”

THE WITHIN FIELD SPATIAL PATTERN OF THE LARVAL EGYPTIAN ALFALFA WEEVIL, HYPERA BRUNNEIPENNIS (COLEOPTERA: CURCULIONIDAE): AN APPLICATION OF PARAMETER ESTIMATES IN SIMULATION

“…As expected, the larval populations begin in a highly aggregated pattern (i.e., the eggs are deposited in clumps), which stabilize rather quickly to a less aggregated condition (1 < i / F~2 ) with no apparent effect on dispersion from the changing population density. Discussion Studies by Miller et al (1972) and Guppy et al (1973, on a closely related species of alfalfa weevil, report larval populations conform to an aggregated distribution; Latheef and Pass (1974), studying the same species, present findings of both aggregated and random larval populations. The latter relate this difference in distribution to larval density: random distributions encountered at high population levels.…”

THE BIOLOGY OF THE LESSER CLOVER LEAF WEEVIL, HYPERA NIGRIROSTRIS (FABR.) (COLEOPTERA: CURCULIONIDAE), ON RED CLOVER, TRIFOLIUM PRATENSE L., IN SASKATCHEWAN

“…Aggregation has been shown to decrease between successive developmental stages of a number of insect species including Pieris rapae (L.) and Hyperapostica (Gyll.) (Harcourt 1961;Miller et al 1972).…”

“…P2 larvae often were located in stipules (near the base of the shoot) during June and early July and in buds and flowerheads by the 2nd week in July. (Harcourt 1961;Miller et al 1972). Weiss (loc.…”