ESTATE CROPS NEWS – One of the main constraints on the growth of coffee seedlings in the greenhouse is pests lice green scales (Coccus viridis) and Aphids (Aphids gossypii) that can inhibit the growth of plants. Competition in utilizing nutrients can cause the attacked plants to become more severe, even some plants to be dead. This study aims to determine the population dynamics of C. viridis and A. gossypii on arabica coffee seedlings of Sigarar Utang, Kartika, and S795 varieties.
The study was conducted in the greenhouse of Indonesian Center For Estate Crops Research and Development, from August 2011 to January 2012. 200 seedlings of arabica coffee consisting of S795, Sigarar Utang, and Kartika varieties were planted in polythene bags in the greenhouse.
Observations were made every two weeks for ten times the observations by calculating the pest populations and compare population growth of C. viridis and A. gossypii by regression method and t test. It was found that mite green scale (C. viridis) population were more dominant than the aphids (A. gossypii) population, with a total population of green scales (C. viridis) as much as 81.23%. Green scales (C. viridis) and aphids (A. gossypii) were found more abundant in the Kartika seedlings compared to Sigarar Utang and S795 varieties. It is easier for the pests to obtain their food by sucking the liquid inside in the branches.
The growth population of C. viridis forming a straight line for 5 months with r values respectively, Sigarar Utang is 0,98; Kartika is 0,98; and S795 is 0,97. Growth population of A. gossypii forming straight lines with the value of r : Sigarar Utang is 0,99; Kartika is 0,98; and S795 is 0,99.
Key words: Coffea arabica, population dynamics, Aphis gossypii, Coccus viridis