Biology of the lebanese cedar shoot moth Parasyndemis cedricola Diakonoff (Tortricidae) in Lebanon

Nasri Kawar

Ent e.,:p & appl. 24(1978) 109--112 Ned Entomol Ver. 4msterdam S H O R T COMMUNICATION S. H. BALOCH~ and N. S. KAWAR: Biology of the lebanese cedar shoot moth Parasyndemis cedricola Diakonoff ( Tortricidae ) in Lebanon. The cedar of Lebanon, Cedrus libani Loud, grows in Asia Minor chiefly in the groves of the Arz Barouk Forest in Mount Lebanon and at Cedars in the North, at 1800 m. They are also found growing on the higher slopes of Taurus and antiTaurus mountains in Turkey (Holm, 1972). The lebanese cedar shoot moth, Parasyndemis cedricola causes severe damage to cedar trees. The larvae mine in the needles and later in the buds. The full-grown larvae also feed on the developing buds in the spring. The damage can be serious because the terminal shoots of young trees are infested. The biology of this species described by Diakonoff (1974), was unknown and it had been observed in the cedars for at least 5 years. A related species P. histrionana (Frohlich) has been reported from the Alto Adige region of N.E.Italy, damaging silver fir, Abies alba in a mixed forest (Zangheri & Masutti, 1963). The research was done on Arz Barouk cedars in an old grove and in new plantations on the western slope of the Mount Lebanon, and in the Laboratory. Ten old trees and ten younger ones were selected at random. Infested shoots were collected from the bottom, middle and upper terminal shoots at 10--15 days intervals. Third-stage larvae collected end of May 1973, were reared in petridishes and glass jars on cedar shoots until pupation. Mass rearing was done in a large cage (23 x 28 • 36 cm) on cedar shoots. Emergence of moths was recorded daily and the sex noted. The newly emerged moths were kept in pairs on cedar shoots and the number of eggs laid per female was recorded. The greyish-brown moths, approx. 18.5 mm (q? q?) and 15.7 mm (c~c~) long, emerged from pupation in early June until early July in 1973-1974. The peak emergence occurred in the middle of June. In the laboratory males usually emerged 2--3 days earlier than females both during the day and at night. During the daytime the newly emerged moths settled in the needle clusters and shoot bases from where they moved to the needle tips during the night. Of a total of 210 moths hatched in 1974, 129 were females and 81 were males. ') School of Agriculture, American Umverslty of Beirut, Lebanon; present address: Department of Entomology, Purdue University W. Laffayette, Indiana, U.S.A. I l0 SHORT COMMUNICATION Fig. 1 Egg-layingpattern ofParasyndemiscedricolaon a cedar tree needle The mating occurred during the early morning and usually lasted 35--50 min. Females in the laboratory readily laid eggs, mostly on the cedar needles in an alternating pattern (Fig. 1) with a maximum of 28 on one needle. Oviposition took 6--9 days. Most eggs were laid 3 days after mating. In the field, the distal shoots of exposed branches are mostly selected for oviposition, eggs being laid on the needles near the tips of the branches and also on the bark of the shoots. The egg laying was observed on both young and on old trees. Per female 90--142 (average 126) eggs were laid from mid-June to mid-July. The eggs are yellow to pink, about 1 mm long. The mean incubation period in the laboratory was 9.2 days (range 7--12). The caterpillar passes through five instars before pupation. The newly emerged larva is yellowish-white to pink with a dark head. The older caterpillars are light greenish to greyish-brown. They grow up to 1.2 cm. Damage: first- and second-stage larvae of P. cedricola mine and then bind four to six needles together with silken threads. The injured needles become loose, turn pale and fall-off the needle-cluster. The older larvae make several webs and feed on the needles as well as on the buds destroying them. In spring the full-grown larvae are very active.The fallen pale-coloured needles can be observed under the SHORT COMMUNICATION l ] trees. The injury caused by the full-grown larvae in spring is more severe than that caused by the young larvae in late s u m m e r and autumn. Larval feeding ceases in m i d - N o v e m b e r and they make hibernation sites by covering a dry, mined bud with a protective silk layer. Dry needle bundles also afforded a protective covering for hibernating larvae. In the spring, new webs usually spun near undamaged buds and shoots are the first sign that the caterpillars have resumed their activity. They feed on the new sprouts and are very injurious. Web formation continues until end of May, when the larva pupates by making a pupal c h a m b e r of loose silks in the hollow bud where the last feeding occurred. The larval skin is shed at the lower end of the c h a m b e r while posterior end of the pupa rests in a shallow circular depression. The pupa is obtect, rather slender, spindle shaped, and about 9 mm long with a rounded head, glossy and of medium built. Strong dark spines are present on the abdominal tergites which are moderately projecting on the second to eight abdominal tergites. Each tergite has two horizontal rows of spines (Fig.2). Spines Fig. 2 Dorsal side of the pupa of Parao'ndemi~ cedrtcola showmg two rows of sprees from 2nd-8th abdominal segments of the anterior row are protruding and larger in size than those of the posterior row. The cremaster is well developed and possess three pairs of spines. Pupation continued until the third week of June, both in the laboratory and in the field. Most p u p a e were found near the outer terminal shoots. The pupal period takes about t2 days (range of 10--16). I [2 SHORT COMMUNICATION r 3rd ~A ,J \,,. \V 9 omo. o~ g g layix~g Fig. 3 Seasonal history of Paravyndemts cedricola at Arz Barouk, Lebanon for the years 1973-- 1974 The life cycle of one generation of the moths during one season is shown in Fig. 3. The pest has no other host plant than C, libani, and has not been reported from any other area. Three species of larval hymenopterous parasites were obtained in the laboratory. The authors thank Dr. A. S. Talhouk, Professor of Economic Entomology and Dr. Shaukat A. Chaudhry, Senior Lecturer in Taxonomy, American University of Beirut, Lebanon, for guidance. REFERENCES DIAKONOFF, A. 0974). A new species of Tortncldae, injurious to Cedars in Lebanon (Lepidoptera). Ent Bet. Amsterdam 34: 210--212. HOI.M, R W. (1972). Cedar In: Encyclopaedia Britannica. Vol. 5 ZANGHFRI, S & MASUTTI, L. (1963.) Notes on the blonomlcs of Enarmoma rufimitrana and other tortncids injurious to SAver Fir in Alto Adige Montt e Boschi, 14" 147--157. (Abstract. Rev Appl Ent (A)53'272(1965). Accepted for pubhcatum May 26, 1978

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Biology of the lebanese cedar shoot moth Parasyndemis cedricola Diakonoff (Tortricidae) in Lebanon

Biology of the lebanese cedar shoot moth Parasyndemis cedricola Diakonoff (Tortricidae) in Lebanon

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