Life table parameters of Tetranychus kanzawai Kishida (Acari: Tetranychidae) on six red bean genotypes

Abstract

Tetranychus kanzawai Kishida (Acari: Tetranychidae) is considered an important pest of different crops; its damage significantly has increased in recent years in some regions of Iran. The life history parameters of T. kanzawai on six red bean genotypes (KS31288, KS31292, KS31287, KS31285, Akhtar and Goli) at 28 ± 1 oC, 50 ± 10% RH and a photoperiod of 16:8 (L: D) h were studied. The life table was constructed considering the female characters of the studied cohort. The developmental time of T. kanzawai differed among tested genotypes and ranged from 8.50 days on KS31285 to 9.77 days on KS31292. The highest and lowest value of immature survival rate were 0.85% on KS31285 and 0.77% on KS31287, respectively. The total fecundity varied significantly on different genotypes, being the highest on KS31288 (71.40 eggs) and the lowest on Akhtar (19.44 eggs). The mean generation time ( T ) was shortest on Akhtar (8.54 days) and longest on KS31288 (12.09 days). The lowest intrinsic rate of natural increase ( r m ) was recorded on KS31287 (0.229 day -1 ) and the highest values of this parameter were obtained on KS31288 (0.303 day -1 ). According to our results, KS31288 and KS31287 were partially susceptible and resistant genotypes to T. kanzawai , respectively. The findings of this study provide new insights to design a more comprehensive pest management program for this pest.