Constant temperature studies on the feeding, reproduction, and development of Amblyseius hibisci ... more Constant temperature studies on the feeding, reproduction, and development of Amblyseius hibisci (Chant) when fed Malephoru croceu (Jacq.) pollen, provided the data necessary to construct life tables and life stage developmental curves. When fed exclusively on a diet of all life forms of Punonychus citri (McGregor), none of the mature, F, A. hibisci females deposited a single egg; moreover, complete immature mortality occurred at 32 and 35 "C. Prior to their deaths, individuals of both sexes exhibited a dark-red occlusion of varying sizes within the alimentary tract near the distal end of the opisthosoma. This symptom was accompanied by increased lethargy, dorsalventral flattening and concaving of the body. These observations were not evident for A. hibisci fed with pollen.
Amblyseius (Neoseiulus) californicus is an indigenous mite in Japan that feeds on many spider mit... more Amblyseius (Neoseiulus) californicus is an indigenous mite in Japan that feeds on many spider mite species. We evaluated the development, survivorship and life-history parameters of A. californicus on a diet of eggs of Tetranychus urticae (red form). More than 97.3% of A. californicus eggs hatched and more than 81.6% of newly hatched larvae attained maturity at temperatures between 15 and 35 8C. Females oviposited at 37.5 8C, but no eggs hatched. At 40 8C, no females laid eggs. The lower threshold temperature from egg to oviposition was 10.3 8C and the thermal constant was 86.2 degree-days. Based on these data, the maximum number of generations that could complete development in a year under field conditions in Ibaraki, central Japan, would be between 21 and 28. At 25 8C, females laid a mean of 41.6 eggs during a mean oviposition period of 19.4 days. The intrinsic rates of natural increase (r m ) were 0.173 at 20 8C, 0.274 at 25 8C and 0.340 at 30 8C. # 2004 Kluwer Academic Publishers. Printed in the Netherlands. Experimental and Applied Acarology 15-30, 2004. 32:
Knowledge of population growth potential is crucial for studying population dynamics and for esta... more Knowledge of population growth potential is crucial for studying population dynamics and for establishing management tactics for pest control. Estimation of population growth can be achieved with fertility life tables because they synthesize data on reproduction and mortality of a population. The Þve main parameters associated with a fertility life table are as follows: (1) the net reproductive rate (Ro), (2) the intrinsic rate of increase (r m ), 3) the mean generation time (T), (4) the doubling time (Dt), and (5) the Þnite rate of increase (). Jackknife and bootstrap techniques are used to calculate the variance of the r m estimate, which can be extended to the other parameters of life tables. Those methods are computer-intensive, their application requires the development of efÞcient algorithms, and their implementation is based on a programming language that encompasses quickness and reliability. The objectives of this article are to discuss statistical and computational aspects related to estimation of life table parameters and to present a SAS program that uses jackknife to estimate parameters for fertility life tables. The SAS program presented here allows the calculation of conÞdence intervals for all estimated parameters, as well as provides one-sided and two-sided t-tests to perform pairwise or multiple comparison between groups, with their respective P values.
... GD Broufas, ML Pappas, DS Koveos. (2007) Development, Survival, and Reproduction of the Preda... more ... GD Broufas, ML Pappas, DS Koveos. (2007) Development, Survival, and Reproduction of the Predatory Mite Kampimodromus aberrans (Acari: Phytoseiidae) at Different Constant Temperatures. Environmental Entomology 36:4, 657-665 Online publication date: 1-Aug-2007. ...
Constant temperature studies on the feeding, reproduction, and development of Amblyseius hibisci ... more Constant temperature studies on the feeding, reproduction, and development of Amblyseius hibisci (Chant) when fed Malephoru croceu (Jacq.) pollen, provided the data necessary to construct life tables and life stage developmental curves. When fed exclusively on a diet of all life forms of Punonychus citri (McGregor), none of the mature, F, A. hibisci females deposited a single egg; moreover, complete immature mortality occurred at 32 and 35 "C. Prior to their deaths, individuals of both sexes exhibited a dark-red occlusion of varying sizes within the alimentary tract near the distal end of the opisthosoma. This symptom was accompanied by increased lethargy, dorsalventral flattening and concaving of the body. These observations were not evident for A. hibisci fed with pollen.
Amblyseius (Neoseiulus) californicus is an indigenous mite in Japan that feeds on many spider mit... more Amblyseius (Neoseiulus) californicus is an indigenous mite in Japan that feeds on many spider mite species. We evaluated the development, survivorship and life-history parameters of A. californicus on a diet of eggs of Tetranychus urticae (red form). More than 97.3% of A. californicus eggs hatched and more than 81.6% of newly hatched larvae attained maturity at temperatures between 15 and 35 8C. Females oviposited at 37.5 8C, but no eggs hatched. At 40 8C, no females laid eggs. The lower threshold temperature from egg to oviposition was 10.3 8C and the thermal constant was 86.2 degree-days. Based on these data, the maximum number of generations that could complete development in a year under field conditions in Ibaraki, central Japan, would be between 21 and 28. At 25 8C, females laid a mean of 41.6 eggs during a mean oviposition period of 19.4 days. The intrinsic rates of natural increase (r m ) were 0.173 at 20 8C, 0.274 at 25 8C and 0.340 at 30 8C. # 2004 Kluwer Academic Publishers. Printed in the Netherlands. Experimental and Applied Acarology 15-30, 2004. 32:
Knowledge of population growth potential is crucial for studying population dynamics and for esta... more Knowledge of population growth potential is crucial for studying population dynamics and for establishing management tactics for pest control. Estimation of population growth can be achieved with fertility life tables because they synthesize data on reproduction and mortality of a population. The Þve main parameters associated with a fertility life table are as follows: (1) the net reproductive rate (Ro), (2) the intrinsic rate of increase (r m ), 3) the mean generation time (T), (4) the doubling time (Dt), and (5) the Þnite rate of increase (). Jackknife and bootstrap techniques are used to calculate the variance of the r m estimate, which can be extended to the other parameters of life tables. Those methods are computer-intensive, their application requires the development of efÞcient algorithms, and their implementation is based on a programming language that encompasses quickness and reliability. The objectives of this article are to discuss statistical and computational aspects related to estimation of life table parameters and to present a SAS program that uses jackknife to estimate parameters for fertility life tables. The SAS program presented here allows the calculation of conÞdence intervals for all estimated parameters, as well as provides one-sided and two-sided t-tests to perform pairwise or multiple comparison between groups, with their respective P values.
... GD Broufas, ML Pappas, DS Koveos. (2007) Development, Survival, and Reproduction of the Preda... more ... GD Broufas, ML Pappas, DS Koveos. (2007) Development, Survival, and Reproduction of the Predatory Mite Kampimodromus aberrans (Acari: Phytoseiidae) at Different Constant Temperatures. Environmental Entomology 36:4, 657-665 Online publication date: 1-Aug-2007. ...
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