In this paper, we investigate the complex dynamics of a spatial plankton-fish system withHolling type III functional responses. We have carried out the analytical study for bothone and two dimensional system in details and found out a condition for diffusiveinstability of a locally stable equilibrium. Furthermore, we present a theoreticalanalysis of processes of pattern formation that involves organism distribution and theirinteraction of spatially distributed population with local diffusion. The results ofnumerical simulations reveal that, on increasing the value of the fish predation rates,the sequences spots → spot-stripe mixtures → stripes → hole-stripe mixtures holes → wavepattern is observed. Our study shows that the spatially extended model system has not onlymore complex dynamic patterns in the space, but also has spiral waves.

Experiments on development of Amblyseius longispinosus Evans (Acari:Phytoseiidae) as influenced by castor pollen as an alternate food and its interaction with sorghum mite, Oligonychus indicus Hirst (Acari:Tetranychidae) were conducted under laboratory conditions. A. longispinosus showed poor growth on castor pollen. Female and male developmental periods were 2.6 ± 0.30 and 2.42 ± 0.21 days on spider mites, 2.70 ± 0.89 and 2.68 ± 0.39 days on spider mites + castor pollen and 5.12 ± 2.03 and 3.89 ± 1.80 days on castor pollen alone, respectively.

At interaction A. longispinosus suppressed populations of O. indicusat 1:10, 1:20, 1:30, 1:40 and 1:50. Prey elimination was on 12th day in 1:10, 18th day in 1:20, 20th day in 1:30, 24th day in 1:40 and on 30th day in 1:50 ratio.