Impact of Insecticides and Surfactant on Lettuce Physiology and Yield

$28.00 plus tax (Refund Policy)

Buy Article:


Insecticides are used extensively on lettuce, Lactuca sativa L., grown in southwestern Arizona because of heavy insect pressure that can potentially reduce lettuce productivity. Multiple sprays are made per season to manage these insects in lettuce. One of the major concerns related to extensive insecticide applications in lettuce is the potential subtle impact of insecticides that may reduce lettuce photosynthesis and yield. We conducted field and greenhouse experiments to examine the impact of multiple insecticides and surfactant spray applications on lettuce photosynthesis and yield. Lettuce was planted in the field in 1998, insecticides and surfactant were applied, and lettuce gas-exchange and dry weights were determined. Treatments were arranged in a split-plot consisting of insecticides as main plot and surfactant as subplot treatments in a randomized complete block design with four replications. Photosynthetic rates of lettuce were significantly reduced by endosulfan, methomyl, acephate, and surfactant at seedling stage 4 h and 2 d after the spray application was made. However, the reduction in lettuce photosynthesis by these insecticides and surfactant was only transient, and lettuce photosynthesis recovered 5 d after the spray application was made. Photosynthetic rates were not altered by zeta-cypermethrin, emamectin benzoate, and spinosad at the seedling stage. Insecticides or surfactant (Kinetic, a nonionic surfactant) did not significantly affect lettuce photosynthesis after rosette formation. In addition, lettuce dry weight was not significantly altered. These studies suggest that lettuce photosynthesis may be susceptible to some insecticides at the seedling stage. Consequently, we found that biorational insecticides, introduced to manage insect pests in lettuce, have no influence on lettuce physiology at the seedling stage, unlike the chlorinated hydrocarbons, organophosphates, or carbamates tested in this study. In a greenhouse study, we found that lettuce photosynthesis and yield were not altered by Bacillus thuringiensis application. Our results indicate that B. thuringiensis and the newer insecticides, particularly biorationals, can be used to manage lettuce insect pests without significantly altering lettuce gas-exchange and yield.

Keywords: Lactuca sativa; dry weight; insecticide; lettuce; photosynthesis; surfactant

Document Type: Research Article


Publication date: June 1, 2000

More about this publication?
  • Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.
  • Editorial Board
  • Submit a Paper
  • Subscribe to this Title
  • Information for Advertisers
  • Visit this journal's homepage
  • ingentaconnect is not responsible for the content or availability of external websites
Related content



Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more