EGG STORAGE OF Podisus nigrispinus (HEMIPTERA: PENTATOMIDAE) PREDATORS AT LOW TEMPERATURES

Abstract

-Podisus nigrispinus are bedbug predators that are used as biological control agents of defoliating larvae in eucalypt plantations. The mass rearing of natural enemies produces large numbers of insects, but the number of predators produced may not coincide with the timing of the outbreaks of pest populations in the field. The aim of this study was to evaluate the effects of different storage periods on the eggs of P. nigrispinus at low temperatures of 5, 13 and 15°C. The treatments consisted of periods of 5, 10, 15 and 20 days of storage of predator eggs at each temperature indicated. After the different periods of storage, the eggs were removed, and the egg viability, the survival and duration of nymphal instars and the sex ratio of emerged adults were evaluated. Egg storage at 5°C reduced the percentage of hatched eggs, while viability values close to 50% were observed for storage periods of up to 10 days at 13°C and up to 15 days at 15°C. For these treatments, the survival rates of nymphs were similar to those of the control. The different storage periods had no effect on the duration of the nymphal stage or the sex ratio of P. nigrispinus at any of the temperatures. Therefore, the storage temperature of 5°C caused the death of the majority of the embryos, while it is possible to store P. nigrispinus eggs up to 10 and 15 days at 13 and 15°C, respectively. Keywords: Biological control; Mass rearing; Cold storage. ARMAZENAMENTO DE OVOS DO PREDADOR Podisus nigrispinus (HEMIPTERA: PENTATOMIDAE) EM BAIXAS TEMPERATURASRESUMO -Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae) são percevejos predadores utilizados como agentes de controle biológico de lagartas desfolhadoras em florestas de eucalipto. Criações massais de inimigos naturais produzem grande número de insetos, mas o número de predadores produzidos pode não coincidir com a época de surtos populacionais de pragas no campo. O objetivo deste trabalho foi avaliar o efeito de diferentes períodos de armazenamento em ovos de P. nigrispinus em baixas temperaturas (5 °C, 13 °C e 15°C ). Os tratamentos consistiram dos períodos de armazenamento (cinco, 10, 15 e 20 dias) dos ovos do predador nas temperaturas indicadas. Após os períodos de armazenagem, os ovos foram retirados e avaliados os parâmetros: viabilidade dos ovos, sobrevivência e duração do estádio ninfal e razão sexual dos adultos emergidos. Os períodos de armazenamento de ovos a 5°C reduziram a porcentagem de ninfas eclodidas inviabilizando a maioria dos ovos. Enquanto valores de viabilidade próximos a 50% foram observados para os períodos de armazenamento de até 10 dias para 13 °C e 15 dias armazenados a 15 °C, com taxas de sobrevivência de ninfas, similares às do controle. Não houve efeito na duração do estágio ninfal e na razão sexual de P. nigrispinus nos tratamentos 878

Effect of cold storage on the pupal development of two pollinators, Eristalinus aeneus and Eristalis tenax

“…This technique presents multiple advantages: it allows the storage of sufficient numbers of beneficial insects for release in the field when required, improving the efficiency of the rearing process (Leopold et al, 1998;Prasad & Ansari, 2000;Colinet & Hance, 2010;Rathee & Ram, 2018). It permits synchronisation of the life cycles of multiple cohorts, facilitating the availability of beneficials during periods of high demand (Riddick & Wu, 2010;Costa et al, 2016). It ensures sufficient stocks if any unexpected problem compromises production, such as disease, failure to keep the correct conditions, or genetic deterioration (Leopold, 2007).…”

Effect of cold storage on development and demographic parameters ofScolothrips longicornisfed on two-spotted spider mite

“…: Anthocoridae) (Bueno et al ., 2014), Rodolia cardinalis (Col.: Coccinellidae) (Abdel-Baky et al ., 2015), Podisus nigrispinus (Hem. : Pentatomidae) (Costa et al ., 2016) and Rhyzobius lophantae (Col.: Coccinellidae) (Senal et al ., 2017). But this study is the first experiment about the influence of cold storage for various storage durations on S. longicornis .…”

Effects of cold storage on the developmental biology of Tenebrio molitor L., 1758 (Coleoptera: Tenebrionidae) at different larval stages

“…It was found that adults decreased compared to the control group, but no change was observed between the cold treatment groups. Temperature changes affect the life cycles of insects and vary according to their developmental stages (Ludwig, 1956;Bowler, 1967;Mirth & Riddiford, 2007;Costa et al, 2016;Mitchella et al, 2017;Arbab, 2019). This may be due to an increase in weight with the increase in tolerance to low temperature, as well as an increase in lipid storage (Mitchella et al, 2017;Paul et al, 2017;Beukeboom, 2018).…”

“…Prolongation of exposure to cold may cause irreversible loss of these activities (Rathee & Ram, 2018). Costa et al (2016) found in a study of eggs and nymphs of Podisus nigrispinus Say, 1832 (Hemiptera: Pentatomidae) that most embryos died at 5ºC storage. They suggested that eggs can be stored at 15ºC for a maximum of 15 d.…”