Third International Conference on Radiation Sciences and Applications 12 – 16 November 2012/ Hurghada, Egypt

Ultrastructure of an Olfactory Sensillum on the Leg of Thermal and Gamma Irradiated Cotton Leaf Worm Adult Male HAZAA, M.A.M., EL-DEGWI, M.S and ALM EL-DIN, M.M.S

ABSTRACT The Scanning Electron Microscopy (S.E.M.) was used to study the hind legs of Spodoptera littoralis males, and its sensillae. These investigations revealed the presence of seven types of sensillae distributed among the leg; these are trichoid, chaetica, coeloconica, basiconica, styloconica, auricillica and squamiformia. The distribution and structure of these sensillae were described. Thermal treatment with 33 oC of full grown male pupae and then gamma irradiated with any of the three substerilizing doses (75, 100 and 150 Gy) showed different malformations in the leg sensilla of the first generation. These treatments effect were dose dependant, as it increased with the increase of the dose of irradiation applied.

INTRODUCTION The success of as terrestrial is pant due to their degree of mobility arising from the power of flight or walking with three pairs of legs. The legs have several types of receptors or sensillae which distributed along them and play an important role in the insect behavior. These receptors on legs or sensillae may be in the form of contact chemoreceptors or mechanoreceptors, which play an important role in the final recognition of food, oviposition site, or mate (1). Identification of olfactory and contact chemoreceptors in insect has received the attention of many authors. These receptors have been shown to be involved in the perception of the host plant and oviposition site (2). Also, the mechanoreceptors on the leg provided information during walking or other behavior, in the male, pretarsal setae help to hold female during mating (3).

Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012) 635

Many methods to control cotton leaf worm pest have been utilized.

Among these methods radiation which induced inherited sterility or (F1 sterility). It is considered to be the most promising genetic method for suppression of lepidopteron population (4-5). The irradiated males and their partially sterile descendants are able to compete with wild males. In the view of the fact that any undesirable effects of gamma radiation on sensilla will lead indirectly to failure of irradiated males to disperse strongly, to seek out appropriate niches or to behave synchrony with wild males or to mate. The aim of the present study is to investigate the effect of moderate thermal treatment degree 33°C when used in combined with the three substerilizing dose of gamma radiation 75, 100 and 150 Gy on the morphology of the leg sensillae of the descendant math female of Spodoptera littoralis by using scanning electron microscopes. Moreover, knowledge of the structure and distribution of sensillae of the male leg may shed lights on the behavior of this pest and provide information necessary for successful insect release method. MATERIALS AND METHODS Rearing and maintenance of insects: The culture of the cotton leaf worm, Spodoptera littoralis was maintained continuously in the laboratories of Atomic Energy Authority at Inshas. Larvae were reared on fresh castor-oil plant leaves (Ricinus communies) under laboratory conditions of 27 ± 2oC and 65 ± 5 % R.H. Thermal treatment: Full grown male pupae were subjected to thermal treatment in an incubator adjusted at 33oC for 20 hours. Similar numbers were kept as control at 25 ± 2oC. After thermal treatment, pupae were transferred again to the laboratory conditions and kept till adult emergence. Irradiation treatment: Full grown male pupae were gamma irradiated with 75, 100 and 150 Gy using a Co60 gamma irradiation cell located at Nuclear Research Center at Inshas, with a dose rate of 1 Gy/sec. Untreated pupae were kept as control for comparison. The emerged adult were caged till used. Combination of thermal and irradiation treatment: Groups of full grown male pupae were exposed to a thermal treatment

636 Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012) of 33oC for 20 hours inside a controlled incubator, and then were gamma irradiated at a dose level of 75, 100 and 150 Gy. The emerged adult moths were caged till used. Scanning electron microscopy (SEM): For examination with scanning electron microscope (SEM) the whole leg of freshly killed specimens were removed from the thorax, cleaned by gentle sonification in distilled water and 70 % ethanol for 1 min, attached vertically to aluminum stubs and air-dried before being coated with gold in a vacuum evaporator. Sensilla observation and description were made by using (Joel JSM 5400) scanning electron microscope with an accelerating voltage of 10 KV. RESULTS and DISCUSSION Insects have three pairs of legs, one pair on each of the thoracic segments. Each leg consists typically of six basic segments, articulating with each other and these are coxa, trochanter, femur, tibia, tarsus and pretarsus. The tarsus is subdivided into five tarsomeres that are differentiated from true segments by the absence of muscles. The pre-tarsus consists of a membranous base supporting a median lobe, the arolium, which may be membranous, or partly sclerotized and a pair of claws which articulate with a median process of the last tarsomere. These claws are strong with a broad base and ended with a tough sharp end (Plate 1 A, B and C). The claws are used to grip onto normally rough surface. The developments of the claws are variable; commonly they are more or less equally well developed (Plate 1 A, B and C). The pre-tarsus also ended with three basal spines (Plate 1 A). At the hind leg, the tibia has two pairs of sharp spurs, one in the middle part of it and the other on the end (Plate 1 E and F). Each pair of spurs are in the form of one long and other short. These spurs may help in holding the female during mating. Haiba (6) working on Phthorimaea operculella found that the hind tibia has two pairs of sharp spurs, one on the base and the other on the middle but the tibia of the mid leg is ended with one pair of spurs. The spurs in each pair were differing in length. Also, Faucheux (7) working on nebulella found that the spurs are observed on the mid and hind legs at the base of femur and trochanter. Scanning Electron Microscopy examination of structure of the tarsal segments revealed the presence of seven different types of sensillae. They are chaetica, squamiformia, styloconica, basiconica, coeloconica, auricillica and trichoid.

Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012) 637

1. Sensilla trichoid (T): A trichoid sensillum is a hair-like projection of the cuticle articulated with the body wall by a membranous socket so that it is free to move. It is the most numerous types of sensilla. Three distinct types of sensilla trichoid can be distinguished in the male leg according to the length, curvature and tips. Type 1 Trichoid (T1) is the most numerous and largest type, relatively straight, but hooked at the tip. Type 2 Trichoid 2 (T2) is shorter and more curved than type 1. Type 3 Trichoid 3 (T3) lies among trichoid sensilla and it is curved with a blunt tip and it is the shortest one among the three types. (Plate 1 D, E, F and G; Plate 4 F; and Plate 5 B and C) 2. Sensilla chaetica (Ch) They are the most striking spines of the leg sense organs having spines with variable lengths. They are inserted in the lateral-ventral aspect of the leg. (Plate 1 D, E, F and G; and Plate 2 A) 3. Sensilla basiconica (Bc) They are cone-shaped with rounded tips. Their base is surrounded with a cuticular ring. They are located among trichoids. (Plate 1 E; Plate 3 B and D; and Plate 5 D and F) 4. Sensilla styloconica (St) It consists of ramified stalk ending with cone shaped apex. (Plate 1 A) 5. Sensilla Coeloconica (Co) Each sensillum consists of a depression surrounded by cuticular spines, they are more or less spherical and a pig arising from the center of the depression. (Plate 5 D) 6. Sensilla squamiformia (Sq) They are in the form of slender scales and are usually present among the scales of the tarsi. (Plate1 D, F and H; and Plate 3 B) 7. Sensilla auricillica (Au) They are ear-shaped with a concave upper surface and are usually present in the sensory area. (Plate 1 G; and Plate 5 D) Many morphological studies on the legs sensillae have been made by many authors. Faucheux (7-8) working on moths of Homoesma nebulella and Tineola bisselliella found that there are 3 types of sensillae chaetica, sensillae

638 Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012) campaniformia and hair plates on the tarsi. There are only 2 sensillae (type 1 and type 2) at the fifth tarsomere and the type 4 is located dorsally on the pretarsus (only one). Sensillae campaniforma are located at the level of each articulation, particularly near the epiphysis (fore leg) and on the spurs of mid and hind legs. These are short trichoid sensillae in irregular rows on the lateral and dorsal sides of all transformers of the fore, mid and hind legs, which are distributed between large macrotrichia spines in Heliothis armigera (9). Few sensillae are also observed on the terminal part of the tibia, which have blunt curved tips(10). The function of the sensillae and the spines were discussed by many authors. Tarsal mechanosensillae give tactile information when the sunflower female chooses a suitable site to lay eggs (11-12). The sensillae chaetica can detect substances collected in the grooves of the bristles or on the flowers. In Vanessa indica, similar hairs with sensillae chaetica are machanosensitive (13) and Choristoneura fumiferana (14). The chaetica sensillae located on the middle of the apex of the fifth tarsomere in Heliothis nebulella probably play a particular function. In process of drumming, the spines could abrade the flower surface then juices might exude onto the surface of the flower. The contact thermoreceptive function of tarsal sensillae chaetica was demonstrated in C. fumiferana (14) and E.kuehniella (15). Stork and Evans (16) suggested that the sensillae located on the legs of the Coleopatra appear to be mechanosensillae for providing information during walking or other behavior and pretarsal setae are well developed and help to hold the female during mating. Salma et al. (9) stated that contact chemoreceptors are located on the proboscis and ventral surface of all tarsi in the moth of the American bollworm Heliothis armigera. Also, Clavert (17) found that the fore tarsus of the nympholid Chlosyne lacinia have chemo- and mechanoreception function sensilla. It was suggested that setae, covering legs of psocopteran insects, help in avoiding blowing by wind gusts and other adverse conditions (18-19). Thermal and Irradiation Effect: Generally, the radiation doses have a pronounced effect on the leg parts. The effect of gamma radiation doses (75, 100 and 150 Gy), heat stress 33°C or both on the hind leg especially tarsi and its sensillae were studied. The figures revealed many malformation features in the different parts of legs as:

Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012) 639

1. Claws and pretarsal segment : Irradiation with gamma doses, thermal treatment and both especially at high doses 150 in combined with gamma radiation resulted in malformation of the claws, which show many malformed features. These are broken of the claws at the inner and outsides, which become unpointed at the tips or did not complete its development with breakage tip also it may be more bent or have serrate or irregular shape also the arolium area shrinkage, the scales of pretarsal segment become more scare and have toothed edge (Plate 2 A, B, C, D, E, F and G). The abnormality or malformation in the leg claws induced by radiation was recorded by many authors. Haiba (6) noticed that irradiation caused highly significant increase in the basal diameter of the leg of potato tuber moth Phthorimiaea opercula. The other claw of the middle leg in the sterilized males could not complete its development. Also, El-Akhdar et al. (20) working on Ceratitis capitata noticed that the end of the irradiated tibia showed abnormal swelling as compared with control. The inner side of the irradiated male claw seemed to be broken and showed a saw-like structure from the inner side as compared to control. 2. Tarsal segments and spurs : The tarsal segments revealed many abnormalities in its structure as it was observed in scales which became toothed edged as 33°C treatment (Plate 3 C, D and G; Plate 4 D; and Plate 5 C, D, E, F and G). The scales also fallen leaving empty socked (Plate 3 F; Plate 4 F; and Plate 5 F). These scales may completely degenerate leaving spaces or wide bare area (Plate 3 D and F; and Plate 5 A, E and G). The abnormality or malformation of leg parts as the result of thermal and irradiation treatments may explain the bad motility of the adults, which affect subsequently the courtship behavior or successful mating. This means low competitiveness ability of treated males compared to untreated ones. The two pairs of spurs also showed malformations as it observed in plate (4) where spurs have malformed edged, shrinkage of its length and its hairs disorganized scattered at certain area and scare at the others (Plate 4 C, D and E). These malformed spurs also observed by Hazaa et al. (10) who indicated that malformation was noticed in straight spurs, which were twisted or bent specially in the long mid tibial spur and it was also broken at the tip. The different types of sensillae showed many forms of malformations or abnormalities as it was observed in trichoid sensillae which scattered in some

640 Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012) areas and absent in others leaving spaces between these parts. The trichoid may be bent at the distal end, it has nodulation as its margin, or it was disorganized. These malformation features were observed in plate (2 B), plate (3 C and E) plate (4 A, B, C, E, and F) and plate (5 B, C, E, F and G). These basiconica also, flattened at its top or toothed edge or it was completely disorganized as it was observed at plate (3 B and D) and plate (5 D and E). The auricillica was elongated and have abnormal shape (Plate 5 D); the coeloconica was also malformed and lost its normal appearance (Plate 5 D). These different malformations features of leg sensillae by radiation doses were recorded by El-Kholy and Fadel (21) who stated that gamma irradiation increased the density of the trichoidea and basiconica sensillae on the antennae of the Ceratitis capitata (Weid). Also Hazaa et al. (10) stated the bad effect of radiation on Spodoptera littoralis leg sensillae especially at high doses of 150 and 200 Gy. Quite the opposite of that, El-Shall et al. (22) suggested that the impact of gamma irradiation on the morphology of antennal sensillae of the moth male of Spodoptera littoralis was dose independent. Also, this impact extended from the parental generation to the first generation (F1) with more deleterious effect in F1 than P1. It can be concluded that irradiated males at 150 Gy or combined with thermal treatment of 33°C cannot distinguish the favorite places for mating and feeding. Also, the undesirable effect of gamma irradiation on most insect sensillae, recorded by El-Shall et al. (22) on the antennae of S. littoralis, caused failure of irradiated male to disperse strongly, to seek out appropriate niches or to behave synchrony with wild males or to respond to call females and/or to mate. Quite opposite to this finding, El-Akhdar et al. (20) stated that the sterilizing dose (90 Gy) applied on full grown pupae had no drastic effect on the med fly leg and on its correlated behavior. The gamma irradiation did not affect the coeloconica, auricillica and styloconica sensillae which are chemo-, thermo- or hygrosensitive and machanosensitive. The author stated that irradiation seemed to make the touch better, which resulted in good male mating, since it increased the basal width of the trichoid sensillae and olfactory in function. The author also found that gamma irradiation decreased the length of sensillae chaetica and basiconica since they are chemosensitive in function and are known as organs of touch. Irradiation seemed to make med fly unable to seek their favorite hosts for oviposition, feeding and mating. Finally the results of the study make us to recommend the using of substerilizing doses 75, 100 Gy either alone or in combined with thermal treatment of 33°C which have low

Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012) 641 undesirable effects on leg sensillae indicating successful mobility or courtship behavior and consequently good or successful application of inherited sterility technique (IST) in the interrogated pest management of Spodoptera littoralis.

Plate (1): Scanning electron micrograph of the hind leg of normal Spodoptera littoralis male showing spurs, tarsomeres and different types of sensillae, scales, spines and claws.

642 Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012)

Plate (2): Scanning electron micrographs of the pretrasus and tarsomere segments of the hind leg of male of Spodoptera littoralis treated with either 33oC, 75, 100 or 150 Gy alone or in combined treatments at pretarsal segment showing serrate claws, swollen base claws, unpointed tip claw, more bending of claws, toothed scales, scarcity of scales and shrinkage of arolium.

Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012) 643

Plate (3): Scanning electron micrographs of the hind leg of male of Spodoptera littoralis treated with either 33oC, 75, 100 or 150 Gy alone or in combined treatments at tarsal segment showing toothed squamiformia, toothed edge scales, disorganization of scales, bending and nodulation of trichoid, flattened edge basiconica, fallen scales leaving empty socket.

644 Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012)

Plate (4): Scanning electron micrographs of the Tibia and first tarsal segment of the hind leg of Spodoptera littoralis male treated with either 33oC, 75, 100 or 150 Gy alone or in combined treatments showing short and long spur, disorganization of hair in spur, malformed edge spur, scarcity of scales in tibia, fallen scales at the tibial edge and also shrinkage of spur.

Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012) 645

Plate (5): Scanning electron micrographs of the hind leg of Spodoptera littoralis treated with either 33oC, 75, 100 or 150 Gy alone or in combined treatments at one of the tarsal segments showing bending and scarcity of scales, empty socket, malformed scales, toothed edge basiconica and scarcity of hairs.

646 Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012)

LIST OF ABBREVIATIONS

REFERENCES 1. Boeckh, J.; Kaissling, K.E.; and Scheider, D. (1965): Insect olfactory receptors; Cold Spring Harb. Symp. Quant. Biol., 30: 263-280. 2. Stadler, E. (1984): Contact chemoreception. In W.J. Bell and R.T. Carde (eds) Chemical Ecology of Insects; Chapman & Hall. London, pp. 3-35. 3. Kim, J.L.; and Yamasaki, T. (1996): Sensilla of Carabus (Isiocarabus) Fiducarius Saishutoicus Csiki (Coleoptera: Carabidae); Int. J. Insect Morphol. & Embryol., Vol 25, No ½, pp. 153-172. 4. La chance, L.E. (1967): Genetic methods for control of Lepidopteran species: status and potential; U. S. Dep. Agric., Agric. Res. Serv. Ars. 28.

5. Mastro, V.C. and Schwalbe, C.P. (1988): Status and potential of F1 sterility for control of noxious , In: proceedings, modern insect control: nuclear techniques and biotechnology; G.V. Ramesh (ed), 16-20 Nov. 1987; International Atomic Energy Agency; Vienna 15-40. 6. Haiba, I.M. (1998): Morphological effect of gamma radiation on the legs of potato tuber moth, Phthorimae operculellaea, (Zeller) (Lepidoptera: Gelechiidae); Arab J. Nucl. Sci. Appl., 31 (2), 301-316. 7. Faucheux, M.J. (1991): Morphology and distribution of sensilla on the cephalic appendages, tarsi and ovipositor of the European sunflower

Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012) 647

moth, Homoeosoma nebulella Den. & Schiff (Lepidoptera: ); Int. J. Insect Morphol.; Vol. 20, No 6, pp 291-307. 8. Faucheux, M.J. (1983): Les sensilles des pattes chez la femelle de Tineola biselliela Humm. (Lepidoptera: Tineola); Etude en microscopie electronique a balayaga; Bull. Soc. Sci. Nat. Ouest Fr, (N.S.) 5: 126-33. 9. Salama, H.S.; Sharaby, A.; and Abdel-Aziz, S.H. (1987): Ultrastructure of chemoreceptors in the moth of the American bollworm Heliothis armigera and their response to chemicals; Bull. Entomol. Soc. Egypt, Econ. Ser., 16: 237-262. 10. Hazaa, M.A.M.; El-Shall, S.S.A.; and Alm El-Din, M.M.S. (2006): Scanning electron microscope studies of an olfactory sensillum on the leg of gamma irradiated Spodeptra littoralis adults; Isotope & Rad. Res., 38 (1): 165-182. 11. Calvert, W.H. and Hanson, F.E. (1983): The role of sensory structures and preoviposition behavior in oviposition by the patch butterfly, Chlosyne lacinia; Entomol. Exp. Appl. 33: 179-87. 12. Faucheux, M.J. (1985): Role des tarsomeres et des appendices cephaliques dans le comportement de ponte de Tineola bisselliella Humm. (Lepidoptera: Tineidae); C. R. Acad. Sci. Paris; 300: 493-98. 13. Morita, H.S., Doria, K.T. and Kuwabara, M. (1957): Electrical response of contact chemoreceptors on tarsus of the butterfly Vanessa indica; Mem. Fac. Sci. Kyushu Univ. Ser. E (Biol.) 2: 119-39. 14. Mitchell, B.K. and Seabrook, W.D. (1974): Electrophysiological investigations on tarsal chemoreceptors of the spruce budworm Choristoneura fumiferana (Lepidoptera); J. Insect. Physiol., 20: 1209- 18. 15. Anderson, P. and Hallberg, E. (1990): Structure and distribution of tactile and bimodal taste/tactile sensilla on the ovipositor, tarsi and antennae of the flour moth Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae); Int. J. Insect Morphol. Embryol.; 19: 13-23. 16. Stork, N.E. and Evans, M.E.G. (1976): Tarsal satea in Coleoptera; Int. J. Insect Morphol. Embryol. 5: 219-21. 17. Calvert, W.H. (1974): The external morphology of foretarsal receptors involved with host discrimination by the nymphalid butterfly Chlosyne lacinia; Entomol. Soc. Amer.; 67: 853-56.

648 Ghada A. Mahmoud et al., J. Rad. Res. Appl. Sci., Vol. 5, No. 2(2012)

18. Turner, B.D. (1974b): The abdominal adhesive organs of Caecilius equivocates Mockford (Caecillidae, Psocoptera, Insecta); J. Nat. Hist.; 8: 427-431. 19. Ahmed, E.S. (1987): Studies on the biology of Psocoptera, Ph.D. thesis, Uni. of Wales, UK. 20. El-Akhdar, E.A.H.; Ahmed, Z.A. and Haiba, I.M. (2005); Arab. J. of Nucl. Sci. Appl.; 37 (2), 301. 21. El-Kholy, E.M.S.; and Fadel. A.M. (2003): The use of the scanning microscope to study effects of gamma radiation on the female antennal sensilla of the Mediterranean fruit fly Ceralitis capitata (Weid.); Arab. J. Nucl. Sci. Appl., 36 (1): 237-247. 22. El-Shall, S.S.A.; Shaurub, E.H.; and Alm El-Din, M.M.S. (2004): Morphology of gamma irradiated antennal sensilla in the male moth of the cotton leaf worm, Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) using scanning electron microscopy; Arab J. Nucl. Sci. Appl., 37 (2): 177-189.

اﻟﻤﺆﺗﻤﺮ اﻟﺪوﻟﻲ اﻟﺜﺎﻟﺚ ﻟﻠﻌﻠﻮم اﻹﺷﻌﺎﻋﯿﺔ وﺗﻄﺒﯿﻘﺎﺗﮭﺎ ١٢ – ١٦ ﻧﻮﻓﻤﺒﺮ ٢٠١٢ – اﻟﻐﺮدﻗﺔ - ﻣﺼﺮ

اﻟﺘﺮﻛﯿﺐ اﻟﺪﻗﯿﻖ ﻟﻠﺸﻌﯿﺮات اﻟﺤﺴﯿﺔ ﻷرﺟﻞ ذﻛﻮر ﻓﺮاﺷﺔ دودة ورق اﻟﻘﻄﻦ اﻟﻤﻌﺎﻣﻠﺔ ﺑﺎﻻﺷﻌﺎع واﻟﺤﺮارة ﻣﺠﺪﯾﺔ ﻋﺒﺪ اﻟﺮﺣﻤﻦ ﻣﺤﻤﺪ ھﺰاع ـ ﻣﻰ ﺻﻼح اﻟﺪﺟﻮى* ـ ﻣﺠﺪى ﻣﺤﻤﺪ ﺷﺒﻞ ﻗﺴﻢ اﻟﺘﻄﺒﯿﻘﺎت اﻟﺒﯿﻮﻟﻮﺟﯿﮫ، ﻣﺮﻛﺰ اﻟﺒﺤﻮث اﻟﻨﻮوﯾﮫ، ھﯿﺌﺔ اﻟﻄﺎﻗﺔ اﻟﺬرﯾﺔ، اﻟﻘﺎھﺮه، ﻣﺼﺮ *ﻗﺴﻢ اﻟﻤﻨﺘﺠﺎت اﻟﻄﺒﯿﻌﯿﺔ – اﻟﻤﺮﻛﺰ اﻟﻘﻮﻣﻲ ﻟﺒﺤﻮث وﺗﻜﻨﻮﻟﻮﺟﯿﺎ اﻻﺷﻌﺎع – ھﯿﺌﺔ اﻟﻄﺎﻗﺔ اﻟﺬرﯾﺔ - ﻣﺼﺮ

أُﺳﺘﺨﺪم اﻟﻤﯿﻜﺮوﺳﻜﻮب اﻹﻟﻜﺘﺮوﻧﻰ اﻟﻤﺎﺳﺢ ﻟﺪراﺳﺔ اﻷرﺟﻞ اﻟﺨﻠﻔﯿﺔ ﻟﺬﻛﻮر دودة ورق اﻟﻘﻄﻦ وﻛﺬﻟﻚ ﺷﻌﯿﺮاﺗﮭﺎ اﻟﺤﺴﯿﺔ. أوﺿﺤﺖ اﻟﺪراﺳﺔ أن اﻷرﺟﻞ اﻟﺨﻠﻔﯿﺔ ﺗﺤﺘﻮى ﻋﻠﻰ ﺳﺒﻌﺔ أﻧﻮاع ﻣﻦ اﻟﺸﻌﯿﺮات اﻟﺤﺴﯿﺔ وھﻰ اﻟﺸﻌﺮﯾﺔ واﻟﺸﻮﻛﯿﺔ واﻟﺤﻮﺿﯿﺔ اﻟﻤﺨﺮوﻃﯿﺔ واﻟﻘﺎﻋﺪﯾﺔ اﻟﻤﺨﺮوﻃﯿﺔ واﻷذﻧﯿﺔ واﻟﺤﺮﺷﻔﯿﺔ أﯾﻀﺎ ﺛﻢ دراﺳﺔ ﺗﻮزﯾﻊ ھﺬه اﻷﻋﻀﺎء ﻋﻠﻰ اﻷرﺟﻞ. ﺗﻢ ﻣﻌﺎﻣﻠﺔ ﻋﺬارى اﻟﺬﻛﻮر ﻛﺎﻣﻠﺔ اﻟﻨﻤﻮ ﻣﻌﺎﻣﻠﺔ ﺣﺮارﯾﺔ ﺑﺪرﺟﺔ ٣٣ ﺛﻢ اﻟﺘﺸﻌﯿﻊ اﻟﺨﺎص ﺑﺜﻼث ﺟﺮﻋﺎت ﺗﺤﺖ ﻣﻌﻘﻤﺔ وھﻰ ٧٥ و١٠٠ و١٥٠ ﺟﺮاى وﻗﺪ وﺟﺪ أن اﻟﺘﺸﻮھﺎت ﻓﻰ ﻣﻌﻈﻢ اﻟﻤﻀﺎد اﻟﺤﺴﻲ ﺧﻼل اﻟﺠﯿﻞ اﻷول وﻛﺎﻧﺖ ھﺬه اﻟﺘﺸﻮھﺎت ﺗﺰداد ﺑﺰﯾﺎدة اﻟﻤﻌﺎﻣﻠﺔ اﻟﺤﺮارﯾﺔ واﻹﺷﻌﺎع.