Antibiotic Treatment Reduced the Gut Microbiota Diversity, Prolonged the Larval Development Period and Lessened Adult Fecundity of Grapholita molesta (Lepidoptera: Tortricidae)

Abstract

Grapholita molesta, the oriental fruit moth, is a serious pest of fruit trees with host transfer characteristics worldwide. The gut microbiota, which plays a crucial part in insect physiology and ecology, can be influenced by many elements, such as antibiotics, temperature, diet, and species. However, the effects of antibiotics on G. molesta gut microbiota are still unclear. In this study, we selected five common antibiotic agents to test the inhibition of G. molesta gut microbiota, and found ciprofloxacin shown the best antibacterial activity. After feeding 1 μg/mL of ciprofloxacin, the relative abundance of Actinobacteria and Cyanobacteria decreased significantly, while that of Firmicutes and Bacteroidetes increased. PICRUSt2 analysis indicated that most functional prediction categories were enriched in the G. molesta gut, including amino acid transport and metabolism, translation, ribosomal structure and biogenesis, carbohydrate transport and metabolism, transcription, cell wall/membrane/envelope biogenesis, and energy production and conversion. Finally, ciprofloxacin feeding significantly affected larval growth, development, and reproduction, resulting in prolonged larval development duration, shortened adult longevity, and significantly decreased single female oviposition and egg hatchability. In addition, we isolated and purified some culturable bacteria belonging to Proteobacteria, Firmicutes, Actinobacteria, and cellulase-producing bacteria from the G. molesta midgut. In brief, our results demonstrate that antibiotics can have an impact on G. molesta gut bacterial communities, which is beneficial for host growth and development, as well as helping female adults produce more fertile eggs. These results will thus provide a theoretical reference for developing new green control technology for G. molesta.

The effect of diet composition on the diversity of active gut bacteria and on the growth of Spodoptera exigua (Lepidoptera: Noctuidae)

“…Exposure to antibiotics can lead to significant alterations in the gut microbiota of lepidopterans and other insect orders. Such changes have been associated with adverse outcomes such as elevated mortality, reduced fecundity, prolonged development times, and reduced pupation and pupae malformation ( Gaio et al 2011 , Lin et al 2015 , Raymann et al 2017 , Zhang et al 2022 ). These negative effects may stem from alterations in the energy and nutrient metabolism processes that are influenced by the gut microbiome ( Chen et al 2021 ).…”

“…In some lepidopterans, antibiotic-related perturbation of the gut microbiota has little impact on larval growth and survival, as in Danaus chrysippus and Ariadne merione (Lepidoptera: Nymphalidae) ( Phalnikar et al 2019 ). In others such as the oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), antibiotics negatively affect the larval development period and fecundity ( Zhang et al 2022 ). Altogether, these observations question the importance of the gut microbiome in the growth and development of lepidopterans in mass-rearing conditions.…”

“…Bearing in mind that diet and microbiota interactions could play a pivotal role in shaping insect health ( Zheng et al 2017 , Chen et al 2022 , Zhang et al 2022 ), our goal was to find out how these 2 factors contribute to colony performance in laboratory-reared beet armyworm Spodoptera exigua (Lepidoptera: Noctuidae). The first aim of our study addressed how artificial diets and antibiotic affect the growth and development of S. exigua caterpillars and to relate this to the nutritional content of these diets.…”

Establishment of a Rapid Detection Method for Yeast-like Symbionts in Brown Planthopper Based on Droplet Digital PCR Technology

“…In recent years, the relationship between insects and their symbiotic microorganisms has become a research hotspot. Symbiotics have been found to contribute to insects’ nutrient metabolism [ 1 , 2 , 3 ], development [ 4 , 5 , 6 , 7 ], reproduction [ 8 , 9 , 10 ], speciation [ 11 ], and improvement of the host’s defenses [ 12 ]. The brown planthopper (BPH), Nilaparvata lugens (Homoptera: Delphacidae), a distant migratory pest that feeds only on the phloem sap of rice [ 13 ], is one of the most seriously damaging pests of rice in China.…”

A Diet with Amikacin Changes the Bacteriobiome and the Physiological State of Galleria mellonella and Causes Its Resistance to Bacillus thuringiensis

“…The development of resistant forms of microbiota in the insect gut can cause changes in the metabolic rate of the host species [6,7]. Finally, an imbalance in the gut microbiota may alter the activity of digestive enzymes and food digestibility, as well as reduce host viability and breeding [8][9][10]. Toxicosis progression is often accompanied by an increased count of bacteria belonging to certain groups and an imbalance in the microbiota [11][12][13][14].…”