The Impact Of Additional Nutrients On Mass Production Of Tyrophagus Putrescentiae (Acari: Acaridae) And Its Predator Neoseiulus Barkeri (Acari: Phytoseiidae)

Neoseiulus barkeri (Hughes,1948)(Acari: Phytoseiide), is an important naturalenemy of small plant lfuid feeding arthropods in greenhouses or orchards’. Its majorpreys include thrips, spider mites, and gall mites, etc. Due to its short developmentalduration, low intrinsic mortality, high fecundity, high dispersal capability, highconsumption rate, and relatively developed mass-rearing techniques, N. barkeri isconsidered as one of the best biological control products and has been widely appliedin agriculture systems worldwide. How to further increase production eiffciency ofalternative prey and reduce the cost is an important aspect in predatory mitecommercialization related research. We investigated the impact of additional nutrients(protein or saccharide sources)(diet mass: additive mass10:3) in basic diets onpopulation proliferation, on saccharide and protein content of Tyrophagusputrescentiae，and on life table parameters of Neoseiulus barkeri, as a predator of T.Putrescentiae, and on the duration of massed production of Neoseiulus barkeri. Theresults are as follows:1.T. putrescentiae population increased by318.5times,316.7times,179.9times within6weeks, when yeast powder, glucose, or sugar was added to the basicwheat bran diet, respectively. In contrast, T. putrescentiae population increased byonly70.2times when reared on basic diet. The mass proportion of T. putrescentiae inthe diet-mite mixture is higher when yeast powder, glucose, and sugar was added.2.Yeast powder, glucose, and sugar resulted in increased soluble saccharidelevel of T. putrescentiae. Especially when sugar was added, the soluble saccharidelevel increased by133%. Significant increase (25%) of soluble protein level was onlyobserved when yeast powder was added.3.When fed with T. putrescentiae reared on yeast powder, glucose or sugaradded diets, respectively, the developmental duration of N. barkeri was shortened by2.28d，2.27d，3.20d，and the daily fecundity increased by0.62，0.29，0.42. Proportionof N. barkeri female offsprings is63.9%when fed with T. putrescentiae reared onwheat bran. Yeast powder increased the offspring proportion of females to69.8%，while glucose and sugar reduced the ratio to58.6%，and58.3%，respectively.4.The mean generation time in days was shortened from22.6381to17.5058 when sugar was added. The net reproductive rate (Ro) increased from11.4956to27.3833，16.6528，15.1690when yeast powder, glucose, or sugar was added to thebasic wheat bran diet, respectively. Higher intrinsic increase rates (rm)(0.1553，0.1554)of N. barken were observed, respectively, when yeast powder and sugar were added.The population doubling time in days was shortened from6.4257to4.4607，5.3848，4.4623when yeast powder, glucose, or sugar was added, respectively.5. The duration of reaching to commercial packaging requirement (80mites pergram) is shortened from40to19，23and22days, when yeast powder, glucose andsugar were added to diet of T. putrescentiae, respectively.