Evaluation of <i>Artemia</i> <i>franciscana</i> Cysts to Improve Diets for Mass Rearing <i>Stethorus</i> <i>gilvifrons</i>, a Predator of <i>Tetranychus</i> <i>turkestani</i>

• Main Authors: Jafar Ebrahimifar, Parviz Shishehbor, Arash Rasekh, Seyed Ali Hemmati, Eric W. Riddick
• Format: Article
• Language: English
• Published: MDPI AG 2021-07-01
• Series: Insects
• Subjects: biological control; Coccinellidae; mass rearing; predator; spider mite; <i>Tetranychidae</i>
• Online Access: https://www.mdpi.com/2075-4450/12/7/632

<i>Stethorus</i> <i>gilvifrons</i> is an acarophagous coccinellid distributed in the Mediterranean region and could potentially be mass-reared for the augmentative biological control of <i>Tetranychus</i> <i>turkestani</i> and related species on crop plants. The hypothesis that brine shrimp <i>Artemia franciscana</i> cysts can improve diets for rearing of <i>S</i>. <i>gilvifrons</i> was tested in laboratory experiments. The diet treatments included <i>A</i>. <i>franciscana</i> cysts (D1), <i>A</i>. <i>franciscana</i> cysts plus a vitamin B complex (D2), <i>A</i>. <i>franciscana</i> cysts plus date palm pollen (D3), and <i>A</i>. <i>franciscana</i> cysts plus date palm pollen and <i>Ephestia</i> <i>kuehniella</i> eggs (D4). The results indicated that D1 did not support immature development. D2 supported egg–larval development but not pupal–adult development. Both D3 and D4 supported development to the adult stage and reproduction. However, D4 was the most effective diet, determined by observations of <i>S</i>. <i>gilvifrons</i> oviposition behavior and fecundity. A life table analysis corroborated these results; an intrinsic rate of increase, net and gross reproductive rates, and mean generation time were best for <i>S</i>. <i>gilvifrons</i> fed D4 rather than D3. A mixed diet composed of <i>A</i>. <i>franciscana</i> cysts, date palm pollen, and <i>E</i>. <i>kuehniella</i> eggs can be used to mass rear <i>S</i>. <i>gilvifrons</i>.