Environmental Entomology (1993) 22, 810-817

Walid Kaakeh and James D. Dutcher (1993)
Survival of yellow pecan aphids and black pecan aphids (Homoptera: Aphididae) at different temperature regimes
Environmental Entomology 22 (4), 810-817
Abstract: Constant high temperature regime (30, 34, 37, and 40°C) for 1-5 h decreased mean survival of nymphal and adult stages of Monelliopsis pecanis Bissell and Melanocallis caryaefoliae (Davis) with increasing temperature and time of exposure. Constant low-temperature regime (0, 6, 12, and 15°C) decreased aphid survival with decreasing temperatures and increasing time of exposure. A temperature by aphid interaction was observed, with the greatest mortality being at the extreme high (37 and 40°C) and low (0 and 6°C) temperatures. Aphid stages showed differences in tolerance to all temperature levels. Third and fourth instars and adults of both species withstood a wide range of temperatures better than first and second instars under either regime. M. pecanis tolerated low temperatures better than M. caryaefoliae, but at high temperatures, M. caryaefoliae was more tolerant. Air temperature fluctuations within a pecan tree were measured during July with temperature probes. Air temperature was slightly higher at the edge of the tree crown than near the trunk, otherwise temperatures were very uniform within the tree crown for a given hour of the day.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): James D. Dutcher

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
environment - cropping system/rotation

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Monelliopsis pecanis	Pecan/hickory (Carya)
	Melanocallis caryaefoliae	Pecan/hickory (Carya)