| The predatory mite Amblyseius cucumeris(0udemans) [Neoseiulu cucumeris]vias studied in the laboratory at six constant temperatures to evaluate the influence of temperature on its development. Two spider mites Tetranychus piercei McGregor and Oligonychus mangiferus Rahman et Punjab were also observed under the same conditions to analysize the difference between A. cucumeris and its prey in the biological and ecological characteristics. The life table of laboratory population was established based on the results.The results showed that, only T. piercei McGregor could complete generation development at 36℃. The shortest development durations of A. cucumeris , 0. mangiferus and T. piercei were recorded at 28, 28 and 32℃, and the longest at 16℃.They varied from 8.67 , 7.22, 9. 20 d to 30. 59, 33.14 and 29. 17d respectively. The highest suvival rate of a whole of A. cucumeris , T. piercei McGregor and 0. mangiferus were 90. 65%, 96. 10% and 89.6% at 28℃,32℃ and 24℃ respectively, and the lowest were 36. 79%, 66. 40% and 55.80% at 16℃.The highest fecundities of A. cucumeris , 0. mangiferus and T. piercei were 34. 81, 35. 84 and 40. 14 eggs/female at 24℃, 28℃and 28℃ respectively, and at 32℃, A. cucumeris and 0. mangiferus produced fewest eggs which were 8. 76 and 8. 44 eggs/female, while to T. piercei McGregor it was at 16℃ with a fecundity of 17.88 eggs/female.The development threshold time and effective accumulated temperature for the a whole generation of A. cucumeris , T. piercei McGregor and 0. mangiferus were 10.32, 10.70,8.91 ℃ and117.54,163.64 and 191 day-degrees respectively. It was estimated that A. cucumeris, T. piercei McGregor and 0. mangiferus could finish 41, 28 and 28 generations respectively in Hainan.The population parameters A. cucumeris, T. piercei and 0. mangiferus were offered in the paper. A. cucumeris, T, pi ere ei and 0. mangiferus had the greatest net reproductive rate(R0) at 28, 28, and 24℃ (20. 89, 23. 65 and 27. 33 respectively). At 32℃, A. cucumeris and 0. mangiferus' R0 reached minimum which were 5.50 and 6.00 T. piercei' was 5.10 at 16 ℃ . At 28 ℃ , A. cucumeris and 0. mangiferus had the greatest intrinsic rate of increase(rm) (0. 1782 , 0. 3957), greatest finite rate of increase( A) ( 1.1950, 1.4854), and shortest population doubling time ( 3.89d , 1.75d), and T. piercei McGregor at 32 ℃ .which was 0.3488,1.4174 and 1.99d respectively, rm and A were lowest at 16 ℃ for A. cucumeris , T. piercei and 0. mangiferus , which were 0. 05057, 0.0724, 0. 1111 and 1.0529, 1.0752, 1. 1175 respectively, andp.dtvtas longest at this temperature which were 13.44,9.57 and 6.24 respectively. According to above narrations , it can be conclued that the temperature span of 24 ~ 28 ℃ suited to A. cucumeris and 0. mangiferus, and 28~32℃ to T. piercei .The trials of functional response for mated adults of predatory mite Amblyseius cucumeris on lavae and adults of T. piercei McGregor showed that the mated adults could consume 17.21 larvae 12 h and 3. 81 female 24 h of T. piercei actually 14. 18 lavae and 3. 14 female.Besed on the results, it could be summarized that Amblyseius cucumeris was one of the potential natural enemies. It can serve as an important biocontrol agent against T. piercei McGregor and 0. mangiferus in Hainan.
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