Performance of Arma chinensis reared on an artificial diet formulated using transcriptomic methods

Abstract

An artificial diet formulated for continuous rearing of the predator Arma chinensis was inferior to natural prey when evaluated using life history parameters. A transcriptome analysis identified differentially expressed genes in diet-fed and prey-fed A. chinensis that were suggestive of molecular mechanisms underlying the nutritive impact of the artificial diet. Changes in the diet formulation were made based on the transcriptome analysis and tested using life history parameters. The quantity of pig liver, chicken egg, tuna fish, biotin, nicotinamide, vitamin B6, thiamine, riboflavin, vitamin C, L-glutamine, and sucrose was reduced, and wheat germ oil, calcium pantothenate and folic acid were increased. Ecuadorian shrimp was added as a partial substitute for tuna fish. Several parameters improved over six generations, including increased egg viability, and decreased egg and adult cannibalism. Additionally, several parameters declined, including longer developmental times for 2nd-5th instars, and decreased nymphal weights. The improvements in life history parameters support the use of transcriptome analyses to help direct formulation improvements. However, the decline in some parameters suggests that additional information, e.g., proteomic data, may be useful as well to maximize diet formulations.

Differential Proteomics Analysis Unraveled Mechanisms of Arma chinensis Responding to Improved Artificial Diet

“…Several biological parameters differed between COSM-fed and IAD-fed insects, such as lower egg viability, reduced fecundity, prolonged nymphal development time, higher cannibalism and longer lifespan [ 30 , 32 ]. Juvenile hormone (JH) is used by most adult insects for regulation of various aspects of reproductive maturation and behavior [ 55 , 56 ].…”

“…The insects were reared at RH of 75 ± 5%, 27 ± 1 °C, and a 16:8 (L:D) h photoperiod. We purchased live pupae of COSM from a supermarket in Tianjin and the improved artificial diet (IAD) comprised raw pig liver, tuna fish, chicken egg and Ecuadorian shrimp [ 32 ]. Appearance and body size were used to distinguish 1st to 5th instar nymphs of F7.…”

“…However, the results demonstrated further improvements may be possible. Additionally, some of the biological parameters remained consistent or improved over successive generations in insects reared on the improved artificial diet [ 32 ]. Other studies have also analyzed the relationship between gene expression patterns and diet components of predatory insects [ 33 , 34 , 35 ].…”

Genomic insight into diet adaptation in the biological control agent Cryptolaemus montrouzieri

“…The availability of a cost-effective factitious prey or arti cial diet is key to the successful mass production of arthropod natural enemies for use in biological control [27]. The availability of molecular markers that could be used as early indicators of insect responses to general and speci c nutritional levels may greatly advance the practice of insect mass rearing [28][29][30][31]. However, very few biological control agent species have completely sequenced genomes.…”

“…This nding explores a relationship between diet and regulation of gene expression, and suggests that the decrease in performance might be caused by a dietary nutrient imbalance. Several studies have tried to explore the relationship between gene expression patterns and diet limitation of predatory biological control agents, and have tried to further optimize the diet formulations [28][29][30][31][32]. However, the mechanism about how diet components affect gene expression of these predators is still not clear.…”