Impact Of Crude Protein And Amino Acid Levels In Yeast On Development And Reproduction Of Carpoglyphus Lactis And Its Predator Neoseiulus Californicus(Acari: Phytoseiidae)

Neoseiulus(Amblyseius) calif ornicus has high biological control potential for a variety of small arthropod pests. Traditionally, N. californicus is reared on its natural prey, spider mites, on host plants. Recent research found that N. californicus is also able to complete its life cycle on Carpoglyphus lactis. However, N. californicus reared on C. lactis have longer developmental duration and decreased fecundity. Since nutritions in prey diet might translocate through the prey to the predator and impact development and reproduction of the predator, we aimed at improving the biological features of N. californicus through modifying the nutrition contents of diet for C. lactis. Carpoglyphus lactis were reared on seven commercial yeast products with different level of protein concentrations, investigated the nutrition translocation between diet-alternative prey-N. californicus, to enhance N. californicus productivity, the results were as follows:The population dynamics of C. lactis that were fed on seven yeast with different level of protein concentrations were researched. Carpoglyphus lactis population increased rapidly when reared on yeast with 23.86%, 40.29% and 45.37% protein concentration, respectively. For these three treatments, C. lactis reached its population peaks ca. 28.00, 21.00 and 23.60 days, multiplied 117.05, 167.48, and 115.42 times, respectively. Small population were observed for C. lactis reared on yeast with 25.90% and 32.40% protein concentration, which multiplied below 10.00 times, respectively. Yeast with 1.46% and 1.72% protein concentration failed to sustain C. lactis population. We analyzed the correlations between the concentration of 17 amino acids in yeast products and the maximum growth rate, daily growth rate before the population peak was reached, and population increasing duration of N. californicus, and found that Asparate, Threonine, Serine, Glycine, Alanine, Valine, Isoleucine, Tyrosine, Phenylalanine, Histidine, Lysine, Arginine, Cystine, Leucine, Proline were positively correlated with population growth of C. lactis.Three kinds of yeast products(23.86%, 40.29% and 45.37% protein concentration) were chose leading to rapid population increase of C. lactis for further experiments. The soluble protein concentration of C. lactis reared on these three kinds of yeast products are 67.00, 60.53, 78.25mg/g, respectively. With a mass production procedure, N. californicus reached its population peaks ca. 21.00, 21.00 and 28.00 days after inoculation, and multiplied 4.65, 5.79, and 12.40 times, respectively.We further investigated the impact of C. lactis diet on the life table parameters of its predator, N. calif ornicus. The higher intrinsic increase rates of N. calif ornicus were observed in the treatments when yeast with 23.86%, 45.37% protein concentration were provided for C. lactis(0.15, 0.14) than when yeast with 40.29% protein concentration was provided for C. lactis(0.08). Besides, the highest net reproductive rate(10.61) occurred when N. californicus was supplied with C. lactis fed with 45.37% protein concentration. Among the yeast products tested herein, the one with 45.37% protein concentration lead to the highest N. californicus productivity.