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International Journal of Tropical Insect Science

, Volume 5, Issue 6, pp 469–474 | Cite as

Seasonal Incidence of the Sorghum Earhead Bug, Calocoris Angustatus Lethierry (Hemiptera: Miridae)

  • I. G. Hiremath
  • T. S. Thontadarya
Research Article

Abstract

Seasonal incidence of the sorghum earhead bug, Calocoris angustatus Lethierry, was studied by sowing the crop once in 10 days, throughout the year during 1978 and 1979, as well as by sowing it at fortnightly intervals from early “kharif” to late “rabi” during 1979. The bug was found throughout the year except for a few weeks during March, April and May. The milky stage of the earhead was the most preferred stage compared to pre-flowering, a third flowering, flowering and ripening stages. The adults dominated during pre-flowering and a third flowering stages whereas nymphs dominated during milky and ripening stages. The computed seasonal indices were higher during August (230), September (222), October (224) and January (215) which coincided with blooming and milky stage of sorghum in general fields. Correlation studies between the bug population at the milky stage and maximum temperature indicated negative and significant ((r = -0.2967) relationship, and positive and significant (r = -0.2727) relationship with relative humidity. Low incidence of bugs was observed on the crop sown during June.

Key Words

Sorghum earhead bug Calocoris augustatus seasonal incidence seasonal indices sowing dates hybrid sorghum 

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References

  1. Anonymous (1977) Icrisat, Annual Report 1974–1975, p. 87. Senator Icrisat, Hyderabad.Google Scholar
  2. Ayyar T. V. R. (1963) Handbook of Economic Entomology for South India, p. 516. Controller of Stationary and Printing, Madras.Google Scholar
  3. Balasubramanian C. and Janakiraman R. (1966) Weather in the incidence of earhead bug, (Calocoris anqustatus) on Co. 12 irrigated ‘Cholum’ at Coimbatore. Ind. J. Agron. 11, 167–172.Google Scholar
  4. Croxton F. E. and Cowden D. J. (1964) Applied General Statistics, p. 843. Prentice-Hall, India.Google Scholar
  5. Puttarudraiah M. (1947) Field control of the earhead pests of Jola (Andropogon sorghum). Mysore agric. J. 25, 48–53.Google Scholar
  6. Subbarao D. V. and Paul M. D. (1979) Effect of winter sowing dates and varieties. Sorghum Newsl. 22, 79–80.Google Scholar
  7. Thimmaiah G., Mutalik Desai K. S., Panchabhavi K. S. and Malipatil M. B. (1972) A note on the effect of sowing on the incidence of sorghum earhead bug (Calocoris angustatus Leth.) in North Mysore Region. Sorghum Newsl. 13, 54.Google Scholar

Copyright information

© ICIPE 1984

Authors and Affiliations

  • I. G. Hiremath
    • 1
  • T. S. Thontadarya
    • 1
  1. 1.University of Agricultural SciencesBangaloreIndia

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