Comparative study of poplar lace bug, Monosteira unicostata(Mulsant & Rey) damage on different poplar species and clones in Karaj

Poplar lace bug Monosteira unicostata (Het.: Tingidae) is one of the most important insect pest of Salicaceae family especially poplars in nurseries and plantations. During 2002-2005, damage of poplar lace bug was studied on 15 native & exotic poplar clones belonging to Populus nigra L, Populus deltoides Marsh, P. x. euramericana (Dode) Guinier and also Populus alba L. in two plots in Alborz Research Center of Karaj. In the first stage, poplar clones were planted as randomized complete block design with 3 replications. In any experimental plot, 4 seedlings were evaluated for lace bug damage at 15 day intervals starting in early June until early October. In order to sample, four leaves of each seedling were randomly taken and number of damaged leaves recorded. Numbering method (0 – 4)) was applied for each seedling. The data modified and were analyzed by SAS software. Duncan test (α=1%) was applied to compare the means. Based on three years results, there was significant difference (α=1%) between the means of poplar species and clones in two plots. In terms of three years results of the pest damage in two plots, of all poplar clones, P. alba 44.9 and P. alba 58.57 (in single group) had the highest susceptibility against poplar lace bug. In the first plot, clones of P. deltoides 77.51 and P. deltoides 73.51 (in one group) and in the second plot, P. deltoides 77.51, P. deltoides 73.51 and P. deltoides 69.55 (in single group) showed the highest resistance to poplar lace bug compared to the other clones.