Characterization and functional significance of bacteria associated with rugose spiralling whitefly, Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae) reared on guava plants

Abstract

Rugose spiralling whitefly, Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae) is an introduced phloem feeder of guava. Gut symbiotic bacteria alter the physiology of the host insect. The present study characterized the nine bacterial isolates from the second nymphal stage of rugose spiralling whitefly using seven different bacteria growth media viz., Nutrient Agar (NA), Luria Bertani agar (LBA), MacConkey agar (MCA), Tryptic Soya Agar (TSA), Endo Agar (EA), R2A agar and MRS agar. Among the nine bacterial isolates, chitinase-producing isolates (seven species) were proceeded for biochemical tests, protease and siderophore activities. Out of seven chitinase producers, protease (seven species) and siderophore (two species) producers were identified using skim milk agar and Chromazurol S (CAS) agar plates, respectively. The biochemical tests showed that all bacterial isolates were Gram positive. Bacterial isolates SGRSW2, SGRSW4, SGRSW6 and SGRSW8 showed negative for carbohydrate fermentation, indole production, citrate utilization, starch hydrolysis tests and also, SGRSW4 showed positive for lactose fermentation. 16S rRNA gene sequencing results revealed that Bacillus genus alone is associated with rugose spiralling whitefly which includes Bacillus albus, Bacillus tequilensis and Bacillus altitudinis. Bacterial communities associated with rugose spiralling whitefly offers basic knowledge about their functional significance to study the physiological role in the host insect.