An improved sampling method for heteropsylla cubana crawford (hemiptera: psyllidae) on leucaena leucocephylla
1990
Elder, R. J. | Mayer, D. G.
The distributions of eggs and nymphs of Heteropsylla cubana Crawford on Leucaena leucocephylla were studied at 4 sites in central Queensland. Current visual rating methods for eggs and nymphs were shown to be unsuitable in estimating population densities. Eggs and early instar nymphs of H. cubana were concentrated on the first fully expanded leaf and the 1 or 2 unexpanded leaves nearest to this leaf on the terminal. Both eggs and nymphs were spread over more leaves in terminals with a larger number of leaves. Later instar nymphs migrated to the stem and leaves closer to the apical bud. The small dimensions require that all counts be made under a microscope. Eggs should be counted in situ. Accurate estimates of nymphal populations were made by washing leaves in alcohol to dislodge nymphs. Tables are presented to enable estimation of populations of all instars on 7 terminal types from counts made using the alcohol washing technique.
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