Spatial distribution and sampling plans for Thrips palmi (Thysanoptera

Thripidae) infesting fall potato in Korea

Ki Jong Cho, Sang Hoon Kang, Gwan Seok Lee

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

The spatial distribution of adult and immature Thrips palmi Karny on fall potato, Solanum tuberosum L., on Cheju Island, Korea, was studied over a 2-yr period by visually inspecting potato leaves. The majority of thrips collected from the leaves were observed in the top one-third of the plant. The within-field spatial patterns of adults and immature thrips were aggregated. The slopes and intercepts of Taylor's power law did not differ among adults and immature thrips. A fixed-precision-level sampling plan was developed using the parameters from Taylor's power law and was tested with resampling simulations using eight independent data sets. Over a wide range of densities, the simulation demonstrated that actual sampling precision (d = SEM/mean) values at d = 0.25 averaged <0.24 in all cases. A binomial sampling plan for estimating mean density was developed using an empirical model evaluated at tally thresholds (the minimum number of insects present before a leaf is considered infested) of one, three, five, and eight thrips per leaf. Increasing sampling size had little effect on the precision of the estimated mean regardless of tally threshold (T). However, increasing T had a dramatic effect on precision. The best tally threshold for estimating thrips density based on the applicable density ranges and the precision of the model was T = 5. A binomial sampling plan with a tally threshold of five and a fixed sample size of 30 leaves should be an effective replacement for enumerative counts when thrips average <10 per leaf.

Original languageEnglish
Pages (from-to)503-510
Number of pages8
JournalJournal of Economic Entomology
Volume93
Issue number2
Publication statusPublished - 2000 Dec 1

Fingerprint

Thysanoptera
Thrips palmi
thrips
Thripidae
Korea
Solanum tuberosum
potato
Korean Peninsula
spatial distribution
potatoes
sampling
leaves
immatures
power law
plan
Islands
Sample Size
simulation
Insects
replacement

Keywords

  • Binomial sampling
  • Fixed-precision-level sampling
  • Potato
  • Sampling
  • Taylor's power law
  • Thrips palmi

ASJC Scopus subject areas

  • Insect Science
  • Ecology

Cite this

Spatial distribution and sampling plans for Thrips palmi (Thysanoptera : Thripidae) infesting fall potato in Korea. / Cho, Ki Jong; Kang, Sang Hoon; Lee, Gwan Seok.

In: Journal of Economic Entomology, Vol. 93, No. 2, 01.12.2000, p. 503-510.

Research output: Contribution to journalArticle

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