External Anatomy and Life Cycle of Aphis nasturtii (Hemiptera: Aphididae) Liana Mihaela Fericean 1* and Mihaela Corneanu 2 1 Department Biology and Plant Protection, Faculty of Agriculture, Banat’s University of Agricultural Sciences and Veterinary Medicine “King Michael I of Romania” from Timișoara Aradului Street, nr.119, 300645, Timisoara 2 Department Genetic Engineering, Faculty of Horticulture, Banat’s University of Agricultural Sciences and Veterinary Medicine “King Michael I of Romania” from Timișoara Aradului Street, nr.119, 300645, Timisoara Article Information Received 27 June 2017 Revised 30 July 2017 Accepted 07 November 2017 Available online 15 November 2017 Authors’ Contribution Both authors conceived and designed the study. Mf collected and analyzed data and wrote the article. MC performed biometrical measurements and statistical analysis. Key words Biometrical Measurements, Biology, Aphis nasturtii, External morphology, Ecology. Aphis nasturtii (Kaltenbach) is a cosmopolitan species who can cause direct damage to the plants by extracting the sap, and indirectly it is a vector to 16 plant viruses. The study presents data referring to the external morphological characteristics, to the biometrical measurements and to the life cycle of Aphis nasturtii. The researches have been carried out for a period of four years on the potato and for a period of two years on the orchards from Romania. At the Aphis nasturtii species the smallest length of the body found for aphids captured in Romania was 1.10 mm, while the biggest was 2.40 mm. In the conditions of the Western part of Romania Aphis nasturtii winter egg stage started in October. On the primary host the aphids gave birth parthenogenetically to three generations of fundatrigenous. In July, the winged form migrated to the secondary host, where successive generations have been born through parthenogenetic reproduction. Gynopara in October return to the primary host and give birth to wingless oviparae that mate with males and lay winter eggs. The biometrical measurements of Aphis nasturtii help to complete knowledge on external morphology of this species. By knowledge of biology and ecology of Aphis nasturtii a protocol for the prevention and control can be established. INTRODUCTION B uckthorn aphid, Aphis nasturtii is a member of the order Hemiptera, suborder Aphidinea, superfamily Aphidoidea, family Aphididae. This aphid is nearly globally distributed, located in all but the coldest terrestrial habitats. It has a broad host range, having been recorded on species of over 60 plant families (Blackman and Eastop, 2006), affect various field crops, fruits and vegetables as sucking pests (Aheer et al., 2008; Arshad et al., 2017). Aphis nasturtii is an important vector of potato viruses. It transmits potato viruses Y and A, and potato leaf roll virus (Foster, 2006), beet yellows, and cucumber mosaic virus (Kennedy et al., 1962). Blackman and Eastop (2006) found that this species is implicated in the transmission of at least 15 plant viruses. The buckthorn aphid infests the lower leaves of potato (Dixon et al., 1993). Worldwide, aphids are one of the major problems from two reasons: aphid feeding can cause direct damages by extracting sap, and indirectly by sending a large number of phytopathogenic viruses. Given these considerations, and that there is not enough research on external anatomy and biology of Aphis nasturtii, * Corresponding authors: liana.fericean@gmail.com 0030-9923/2017/0006-2141 $ 9.00/0 Copyright 2017 Zoological Society of Pakistan the research can make notable contributions in this area. Knowing the life cycle of Aphis nasturtii can be essential to effective control measures. METHODS The research has been carried out for a period of six years. The biology of Aphis nasturtii was observed for four years: 2005 - 2008 on potato culture, and in 2015 - 2016 in various orchards from Romania. Alate aphid were collected and preserved in ethanol 80%. Aphids were mounted on slides according to the method of Blackman and Eastop (2000). The biometrical measurements of Aphis nasturtii was done for a total of 300 individuals, species captured from, potatoes and orchards from Didactic Station Timisoara (Timiş County - a plain area) and Varfurile, (Arad County - a mountain area) from Romania. The data were statistically analyzed. Morphometric approaches have been used widely to differentiate between closely related species, populations and biotypes in various insects (Lozier et al., 2008; Barahoei et al., 2011; Lamb, 2011; Ruiz et al., 2014). In aphids alone, there have been a series of studies involving the application of multivariate techniques to the study of morphological variation (Blackman and Spence, 1994; Kawada, 1997; Remaudiere, 1997; Blackman, 2000; Perju, ABSTRACT Pakistan J. Zool., vol. 49(6), pp 2141-2145, 2017. DOI: http://dx.doi.org/10.17582/journal.pjz/2017.49.6.2141.2145