Vol. 109 (1996): Proceedings of the Florida State Horticultural Society
Citrus

APHID POPULATIONS IN A FLORIDA CITRUS TRISTEZA VIRUS SUPPRESSION TRIAL

Published 1996-12-01

Keywords

  • citrus tristeza virus,
  • ctv,
  • hamlin orange,
  • sour orange,
  • rootstock,
  • brown citrus aphid,
  • toxoptera citricida,
  • spirea aphid,
  • green aphid,
  • aphis spiraecola,
  • aphis citricola,
  • melon aphid,
  • cotton aphid,
  • aphis gossypii,
  • elisa,
  • vector
  • ...More
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Abstract

Aphid populations were monitored weekly during a five-year study conducted in a sweet orange scion (Hamlin, Citrus sinensis (L.) Osbeck) on sour orange rootstock young tree planting. Sampling for citrus tristeza virus (CTV) was conducted once a year. Samples for CTV analysis were analyzed using an indirect double-antibody sandwich with enzymelinked immunosorbent assay (ELISA). The presence of CTV was compared to aphid population increases found during the previous year. The 300 tree block was treated with several chemical aphid control regimes (Temik®, Meta-Systox R® and stylet oil) with little or no effect. Mild and severe isolates of CTV were observed throughout the block. Four double-sided 22.5 cm × 13.5 cm Pherocon® A.M. sticky traps posted on the borders of the block were used to catch and monitor aphids. In 88% of the weeks of observation either Aphis spiraecola (Patch), Aphis gossypii (Glover) or both species were the predominant aphids collected. These aphids were most abundant in March, April and May with a slight fall presence peaking in November. An increase in the number of A. spiraecola in 1993 was found to be correlated with a large increase in the presence of CTV in the block in early 1994. No distinct pattern of aphid movement was evident throughout the block.