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Life table parameters and survival rate for Tetranychus urticae Koch were determined on
four bean varieties namely Talash (Colorado bean), Sadaf (Navy bean), Goli (Kidney bean) and
Parastoo (Black-eye bean). Eight cohorts of one day old eggs of T. urticae were placed in
Tashiro cages on the leaves in each of the varieties and preserved in growth chamber with
laboratory conditions of 25±1°C and 60±5 % RH as well as a photoperiodism of 16:8(L:D)
hours. Life table and survival rate of T. urticae were studied on each bean variety up to the death
of the last female mite. The results indicated that the death of the last individual adult female on
Talash, Sadaf, Goli and Parastoo occurred in 24, 23, 23 and 23 days, respectively. Life
expectancy on the four mentioned varieties was estimated as 15.51, 12.77, 13.11, and 11.73
days, respectively as on the first day of adult appearance, which revealed a maximum rate of life
expectancy for Talash variety. On the four mentioned varieties, the mite egg hatch rate was
determined as 83.35, 62.40, 81.35, and 56.95 percent. The survival rate of individuals developed
into adults from the initial cohort stage was reported as 40.40, 25.13, 23.13 and 21.73 percent,
respectively. The results indicate that Talash variety is a more suitable host plant for T. urticae
in comparison with others in the study.