Developmental and reproductive response of Brachmia macroscopa (Lepidoptera: Gelechiidae) to three host plants

Li Ma,Ni Li,Guo-Hua Huang,Ming-Zhu Su,Xing Wang,Yan Liu

doi:10.1038/s41598-018-27415-z

Abstract

The sweet potato leaf folder, Brachmia macroscopa Meyrick (Lepidoptera: Gelechiidae), which is a significant pest of plants in the family Convolvulaceae, is rapidly expanding its range in South China and other subtropical regions. Studies were designed to examine the effects of three different host plants (sweet potato, Ipomoea batatas (L.) Lam.; water spinach, I. aquatica Forsskål; and morning glory, Pharbitis purpurea (L.)) on the development and life table parameters of B. macroscopa under laboratory conditions. We found that the intrinsic rates of increase of B. macroscopa were 0.17 ± 0.004, 0.21 ± 0.005 and 0.16 ± 0.004 on I. batatas, I. aquatica and P. purpurea, respectively. The highest net reproduction rate was 158.06 ± 18.22 per female reared on I. aquatica. The larvae had five instars when reared on I. batatas and I. aquatica, but required six instars on P. purpurea. The mean generation lengths of B. macroscopa ranged from 24.32 ± 0.18 days when reared on I. aquatica to 29.40 ± 0.24 days on P. purpurea. The survival of all stage and fecundity curves was intuitively manipulated using the age-stage-structured and two-sex population life table method, to enable comprehensive descriptions of the stage and population trends of B. macroscopa on the three Convolvulaceae plants. Our results indicated that I. batatas and I. aquatica were more suitable host plants than P. purpurea.

Highlights

IntroductionStudies were designed to examine the effects of three different host plants (sweet potato, Ipomoea batatas (L.) Lam.; water spinach, I. aquatica Forsskål; and morning glory, Pharbitis purpurea (L.)) on the development and life table parameters of B. macroscopa under laboratory conditions
The developmental time of the egg stage was 4 days on I. aquatica and P. purpurea, which was shorter than eggs laid on I. batatas (5 days)
There was no significant difference between I. batatas and I. aquatica in the duration of the 2nd instar (P = 0.448), or in the 3th instar (P = 0.116); nor were there significant differences in the 3th instar stage between I. aquatica and P. purpurea (P = 0.454), the duration of the 2nd instar when fed on I. aquatica was longer than on P. purpurea

Summary

Introduction

Studies were designed to examine the effects of three different host plants (sweet potato, Ipomoea batatas (L.) Lam.; water spinach, I. aquatica Forsskål; and morning glory, Pharbitis purpurea (L.)) on the development and life table parameters of B. macroscopa under laboratory conditions. The sweet potato leaf folder, Brachmia macroscopa Meyrick (Lepidoptera: Gelechiidae), is a widely distributed pest in Europe, Russia, Caucasus, Transcaucasian region, West Kazakhstan, central Asia, Korea, Japan, China, and northern India It mainly damages Dioscorea esculenta, Ipomoea aquatica, Calystegia sepium, Croomia japonica and other crops in the Convolvulaceae family. Based on a two-year field investigation in Changsha, China, we found that local B. macroscopa fed mainly on three Convolvulaceae plants, sweet potato vine Ipomoea batatas (L.) Lam., Chinese waterspinach I. aquatica Forsskål, and Japanese morning glory Pharbitis purpurea (L.). The data provides a theoretical basis for devising and implementing efficient as well as environmentally friendly integrated control procedures

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Conclusion