The Effects of Temperature and Humidity on a Field Population of Bradysia odoriphaga (Diptera: Sciaridae)

Abstract

The production of Chinese chives is reduced throughout China due to a root-feeding dipteran pest Bradysia odoriphaga Yang et Zhang (Diptera: Sciaridae), therefore deciphering the conditions influencing its growth and development are important in developing ecological control strategies. A study was conducted from 2014 to 2017 to determine the relationship between the abundance of B. odoriphaga and temperature (atmospheric and soil), soil water content, and atmospheric humidity in a Chinese chive field in Beijing City, China. Numbers of adults peaked in March and October to November and were lowest in July to August and December to next February; numbers of larvae were highest in December to next February and lowest in July to August. From 2014 to 2017, the numbers of adults and larvae were significantly correlated with monthly mean atmospheric temperatures and soil temperatures, but were not significantly correlated with monthly mean atmospheric relative humidity and soil water content. However, for both adults and larvae, numbers were significantly greater with high soil water contents compared with drought treatment. The results of this study suggest that the very low soil water contents, high atmospheric temperatures, and high soil temperatures were critical for regulating field populations of B. odoriphaga.

Identification and Pathogenicity of a New Entomopathogenic Fungus, Mucor hiemalis (Mucorales: Mucorales), on the Root Maggot, Bradysia odoriphaga (Diptera: Sciaridae)

“…This indicated that extreme temperatures not only restricted the growth and infection of the fungus, but also accelerated nutrient metabolism resulting in less extracellular enzymes and toxic proteins ( Bai et al 2016b ). Previous studies reported that during the emergence peak of B. odoriphaga larvae, the mean soil temperature fluctuates between 15 and 25°C, which would be suitable for the use of M. hiemalis BO-1 to control B. odoriphaga based on our results ( Shi et al 2018 , 2020 ). To sum up, M. hiemalis BO-1 application could provide satisfactory control efficiency during the spring and autumn in open fields, or during winter in the greenhouse.…”

“…Bradysia odoriphaga is an underground insect in its immature stages and adults leave the soil. However, during the emergence peak of B. odoriphaga , the mean soil temperature in fields is typically below 20°C, which is not optimal for many biological insecticides ( Shi et al 2020 ). To sum up, finding an entomopathogenic fungus possessing high pathogenicity and broad environmental adaptability for use against B. odoriphaga appears to be key to improving biocontrol efficiency.…”

Impacts of climate change and host plant availability on the potential distribution of Bradysia odoriphaga (Diptera: Sciaridae) in China

“…37 A high drought in summer will cause a sharp decline in the population of B. odoriphaga. 37 2.1.5 Research method 2.1.5.1. Parameters for Bradysia odoriphaga.…”

“…B. odoriphaga larvae mainly live in the soil at a depth of 0–5 cm. They can develop in a soil moisture range of 12.5–48% 37 . A high drought in summer will cause a sharp decline in the population of B. odoriphaga 37 …”

“…The optimum soil moisture content for the growth of B. odoriphaga larvae was determined to be 12.5-48%. 37 Based on the template parameters from references and CLIMEX, we did some certain adjustments. Therefore, we set SM0, SM1, SM2, and SM3 to 0.075, 0.1, 0.6, and 1.3, respectively.…”