]pn. ]pn. ]. Environ. Entoillo l. Zoo l. 19 (2) : 59 - 67 (2008) 環動昆第19 巻第2号: 59 - 67 (2008) 。riginal Article

Comparisons of cocoon density and survival processes of the blue 幽 striped nettle grub lepida (Cramer) between deciduous and evergreen trees

Hiroichi Hiroichi Sawada 1) ，Y oshihisa Masumoto 1)， Takashi Matsumoto 2) and Takayoshi Nishida 3)

1) 1) School of Environmental Science ，The University of Shiga Prefecture ，日 ikone ， Shiga 522-8533 ， Japan 2) 2) Graduate School of Human and Environmental Studies ，Kyoto University ，Kyoto 606-850 1. Japan 3) 3) Laboratory of Ecology ， Graduate School of Agriculture ，Kyoto University ，Kyoto 606-8502 ， Japan

(Received (Received March 17 ， 2008 ; Accepted May 1， 2008)

Abstract

We studied population dynamics of the blue-striped nettle grub moth Parasa lepida (Cramer) ， in terms of cocoon density density over four years from 2004 to 2007 at the campus of The University of Shiga Prefecture ，Hikone ， western Japan Japan on a wide range of host trees including both deciduous trees (36 spp. of 282 individual trees) and evergreen trees trees (15 spp. of 122 individual trees). Detailed survival processes were examined by tracking developmental stages both both on the deciduous Chinese tallow tree Triadica seb 俳ra (1.) Small (Euphorbiaceae) and an evergreen oak Quercus myrsinaefolia myrsinaefolia Blume (Fagaceae) to identify factors responsible for the population dynamics and the host utilization patterns. patterns. The density of cocoons was significantly higher in deciduous hosts than in evergreen hosts in the first generation ， but this tendency disappeared in the second generation. Life table analyses revealed there was a higher cocoon cocoon density in deciduous T. sebifera than in evergreen Q. myrsinaefolia in the first generation but detected the opposite opposite tendency in the second generation. These generation specific trends were attributable to the greater egg density density and thεhigher survival rate during the larval stage in the first generation ，and to density-dependent occurrence occurrence of larval death due to nuclear polyhedrosis virus (NPV) in the second generation on T. seb( メera.

Key words : Parasa lepida (Cramer) ，Population dynamics ，Life table ， Host plan t， Deciduous tree ，Evergreen trεE

Introduction Introduction Hattori ， 1981). Moreover ， larvae of P. lepida ，

armoured with sharp spines ， are annoying.

The blue-striped nettle grub moth Pa 印刷 lepida P. lepida is highly polyphagous. For instance (Cramer) (Cramer) (: ) is an invasive Robinson et al. (2001) listed 78 species belonging to 35 pest pest originally distributed widely in the tropics and families ， such as Leguminosae ， Arecaceae ， and subtropics ， such as southern China ， south-east Asia ， Euphorbiaceae. as the host plants in and

India ，and central-south Africa (Hirashima ， 1989; Southeast Asia. Moreover ， P. lepid α1S， a notonous pest Zhang ，1994). Invasion of P. lepida was first recorded in of fruit trees ，damaging ，coffee ， and Kagoshima in 1921 but it was rare until the 1960s cacao in Indonesia (Kalshoven ，198 1) and mango (Miyata 1981). Ever since the end of the 1970s particularly in India (Kapoor et al. ，1985; Jeyabalan and outbreaks outbreaks have occurred frequently in western Japan Murugan ， 1996). Extreme polyphagy was also (Miyata ， 1981) together with rapid northward documented in Japan. Yamazaki et al. (1 994) revealed expansion expansion of the distribution range ，now reaching to the presence of cocoons on 194 trees of 85 species northern northern Kanto (Nakano ， 2003). During the 1980s P. belonging to 34 families among a total of 463 trees of lepida lepida established a pest status ，seriously defoliating 166 species belonging to 48 families growing in the cherry cherry trees ，persimmons and various trees on the Botanical Garden of Kyoto University ，Kyoto ， western

streets streets and city gardens in urban areas (Oda and Japan. By tracking cocoon density of P 目 lepia αfor 51

Corresponding Corresponding author : [email protected]

-59 Sa 、，y ada et α/

tree tree species over three years in Hikone. western the start to the end of cocoon spinning ，from late July J apan. Nishida et al. (2006) reported the host to early September in the first generation and from utilization utilization as follows: 1) The cocoon was observed on middle September to early November in the second 26 26 tree species (66.7 %) among 39 common tree generation. On the grounds that P. lepida pupates species ， 2) The cocoon density was relatively high in exclusively in the lower parts of tree trunks ，we the the Japanese red maple Acer pycnanthum ， the Japanese counted the number of cocoons on tree trunks less maple A. palmatum var. matsumurae (Aceraceae) ，an than 2.5 m in height for each census tree. Cocoons evergreen evergreen oak Quercus myrsinaefolia (Fagaceae). and being formed on substratum annexed to a census tree the the Chinese tallow tree Triadic αsebi 耐α(Euphorbiaceae) ， were included in the data of the census tree. To avoid

3) 3) Plant phylogeny may play a minor role in double counting ， each cocoon was marked with a felt determining determining the cocoon density ，and 4) In the first pen after being counted. generation generation the cocoon density was higher among deciduous deciduous species than among evergreen species. Life t且ble In In this study we report the host utilization of P. Life tables of P. lepida were constructed for both T. lepida lepida by comparing the cocoon density between seb すき ra (deciduous tree) and Q. myrsina 宅folia (evergreen deciduous deciduous and evergreen hosts. together with detailed tree) by pooling data of each tree species over 6 survival survival processes of all the developmental stages on generations 企om the first generation in 2005 to the second deciduous deciduous T. seb 俳ra and evergreen Q. myrsinaefolia. By generation in 2007. Both host species were selected

examining examining these data we discuss factors affecting host 四 because of the relatively high cocoon densities and the related related differences in the cocoon density of P. lepida abundance of trees that can ensure large sample sizεs. The numbers of census trees were 10 in 2005 and 13 Materials Materials and Methods in 2006 and 2007 for each tree species. The height and diameter diameter of the census trees were similar for T. sebifera The study area and Q. myrsinaefolia with a tree height of 3.6-6.2 m and

We performed field censuses at the c乱mpus of The 3.0-5.6m ，respectiv 巴ly ，and a tree diameter of 与20 cm

D University University of Shiga Prefecture (USP) (N35 1 7' ，E and 8司 17 cm at 20 cm above the ground ，respectively 136 0 15' ). located in the southern suburbs of Hikone The census periods covered whole developmεntal city ， western Japan. The campus of USP was stages from the beginning of the adult emerg 日nce to constructed constructed in 1995. with 70 species of trees planted in the last formation of the cocoon ，from middle May to the the 30 ha area. The campus was similar to a large early September in the first generation and from scale scale city park ，with a large number of P. lepida August to early November in the second cocoons cocoons observed on the tree trunks During the census periods all thεleaves of the trees trees were checked for the number of eggs and

Census of cocoon density batchεs every other E 乱ch egg batch was We chose a total of 51 tree species comprising 404 individually marked by attaching a label nearby and individual individual trees (36 species of 282 deciduous trees and thereafter mortality factors ， such as hatching failure ， 15 15 species of 122 evergreen trees) among predation ，parasitoids and so on ，were checked. If a approximately approximately 70 tree species planted in the campus. group of newly hatched larvae was found ，nearby

The deciduous trees included T. seb ぴera ，Yoshino leaves were examined intensively for 時 the presence of cherry cherry Prunus X yedoensis ，and J apanese zelkova Zelkova the egg batch from which the larvae derived to count serrata serrata and the evergreen trees included Q. the egg batch size. the number of hatched larvae ，and myrsinaefolia ， Q. glauca ， and Camphor laurel the number of parasitized eggs. Y oung instars are Cinnamomum camphora. The census started from the very conspicuous because they are gregarious with first first generation in 2004 and ended at the second very noticeable feeding scars on leaves. The cocoons generation generation in 2007. over 8 generations during the four were checked using the same methods described in years. years. 1n principle we conducted the censuses on 10 the previous section. trees trees for each tree species except when the maximum number of tree species was less than 10. The censuses Comp 紅色on of life table data between the 何 '0 host plants were performed once a week during the periods from Survival processes were compared between T

-60 一 Comparisons Comparisons density and survival processes o[ the 仇 rasa lepid α

sebif 台ra 呂nd Q. m) 刊 tna そfolia for each generation and log C 礼一 log Cb = (log Ea -log Eb) + (log S a -log S year. year. The cocoon density of a given generation or year (E) b) + (l og S (L) a -log S (L) b) (3) was determined as follows. Equation Equation (3) means that in terms of the common C =E x Ll E x C/L =E xS (E )x S (L) (1) logarithm ，the difference in the cocoon density between the two host plants is expressed as the sum Here ，C ，E ，and L denote the density of cocoons ， of between-plant differences in the following three life eggs ，and hatched larvae ，respectively ，whereas S (E) stage components; egg density (E) ，egg survival (S and S (L) denotεthe survival rate during the egg and (E) )， and larval survival (S (L) ). Then we tried to larv 呂1 stages ，respectively. Consequently ， the relative detect the key stage that accounted most for the host- cocoon cocoon density on T. sebifera to that on Q. myrsina ξfolia related differences in cocoon density by comparing C ， was glven as E ，S (E) ，and S (L) plotted on a common logarithm basis. basis. Ca/Cb= Ea/Eb xS (E) a/S (E) b X S (L)ぁ信 (2) Results and Discussion Here ，a and b，respectively ，indicate T. sebifera and Q. myrsinaefolia. myrsinaefolia. Then Equation (2) can be expressed by Cocoon density on the deciduous and evergreen trees taking taking the common logarithm Fig. 1 shows the cocoon density on the deciduous and evergreen hosts for 8 generations over four years

n.s n.s 2004 2004 2005 C '" '" 0 「一一つ r一一「 o 4 ロdeciduous tre6 0 4 lJ..l O lJ..l O 図 evergreen tree c/) c/) o 十1 3 主 B ~ ~ 2 る E P

st 1st Gen 2nd Gen 1st Gen 2nd Gen

P

1st 1st Gen 2nd Gen 1st Gen 2nd Gen Generation Generation

Fig. Fig. 1 Comparisons of the mean cocoon (Parasa lepid α)， density per tree (:t S.E.) between deciduous and evergreen trees trees from 2004 to 2007. Open bars and gray bars indicate mean densities in deciduous and evergreen trees ， respectively. respectively. The differences in cocoon density between the host trees were tested using Welch's t tes t. n. S.: not significan t.

61 61 Sawada Sawada et at

In In the first generation of 2004 ， the cocoon density per Q. myrsinaefolia. with 844 eggs and 235 eggs ， tree was higher in the deciduous trees (0.67 :i: 0.19; respectively. The tendency was the same in 2006 and m :i: se) than in the evergreen trees (0.05 土 0.05) 2007 ，with 3.2 times and 7.3 times more eggs in T. (Welch's (Welch's t tes t: P

was detected (2.21 :i: 0.52 and 2 目 87 :i: 1. 87 for the Matsumura ，an egg parasitoid ，was identified as the deciduous deciduous and evergreen trees ，respectively ， Welch's t egg mortality agent by rearing parasitized eggs in the tes t: P=0.63) . laboratory. The parasitized eggs were rεadily The same seasonal trend was observed consistently identified due to the darkened coloration. T. dendrolimi throughout the study period up to 2007 (Fig. 1) was also described as an egg parasitoid of another

Limacodidae moth ， the small blackish cochlid

Life tables of the first generation in deciduous Scopelodes contractus Walker (Oda and Hattori ， 1981). Triadica Triadica sebifera and evergreen Quercus myrsinaefolia The mortality rate due to T. dendrolimi. fluctuating Life Life tables of the first generation during 2005 - 2007 from 2.3% up to 36.6% on T. seb 俳ra ， did not exhibit were compared between deciduous T. sebifera and consistent host-related tendencies though all the evergreen Q. myrsina そfolia (Table 1). In 2005 the total between-host differences were statistically significant egg density was 3.6 times higher in T. sebifera than in (P

Table Table 1a. Life tablesof the first generation of p. lepida on T. seb ザera and Q. myrsinaefolia in 2005 Host Host plant Q. Myrsina ι?folia 1¥ 0 at No. of alive at No. of dying

Age Age class beginning of X Factors of Mx Mortality ア rate (%) beginning of X Factors of Mx during X 'v !ortality rate (%) X Nx (l x) MxF Mx/Nx'100 Nx (l x) MxF Mx Mx/N ど1∞ Egg Egg 844 (1000) 235 (10 ∞) parasitoid parasitoid 309 36.6 pa ほasitoid 25 10.6 unknown unknown and unknown and 57 57 6.8 12 5.1 miscellan 印 us miscellaneous Larva Larva 478 (566.4) 198 (842.6) unknown unknown and unknown and miscellaneous miscellaneous 422 88 .3 miscellaneous 193 97.5

Table Table 1b. Life tables of the first generation of p. lepida 口n 主 sebifera and Q. myrsinaefol ωin 2006

Host Host plant T. 日 bifera No. No. of alive at Nαof dying No. of alive at Age Age class beginning of X Factors of 'v lx during X Mortality rate (%) beginning of X Factors ぱ ¥lx during X Mortality rate (%) X I¥ x (l x) ¥!xF 'I lx Mx/Nx'100 Nx(lx) ¥lxF Mx ¥lxi!¥x'100 Egg Egg 3722 (1000) 1172 (1000) parasitoid parasitoid 85 2.3 paγasitoid 70 6.0 unknown unknown and llnknown and miscellaneous miscellaneous 459 12 .3 miscellaneous 71 6.1 Larva Larva 3178 (853.8) 1031 (879.7) unknown unknown and unknown and miscellaneous miscellaneous 2374 74.7 miscellaneous 838 81. 3 Cocoon Cocoon 801 (216.0) 193(164.7)

Table1c 圃 Life tables of the first generation of p. lepida on 主 sebifera and Q. myrsinaefolia in 2007.

Host Host plant T. 日 bi 大m No. No. of alive at No. of dying at Age Age class beginning of X Factors of Mx during X :V lortality rate (%) beginning 01 X Factors of Mx during X Mortality ratc (%) X I¥ x (l x) MxF Mx Mx/Nx'100 Nx (l x) MxF Mx MX."Nx'100 Egg Egg 3437 (1000) 472 (10ω) つ4A parasitoid parasitoid 421 12 .2 parasitoid U 5.1

巧/ヴ unknown unknown and unknown and j miscellaneous miscellaneous 906 26.4 miscellaneous l6.3 Larva Larva 2110 (613.9) 371(786 川 unknown unknown and unknown and miscellaneous miscellaneous 1862 88.2 miscellaneOlls 329 88.7 Cocoon Cocoon 248 (72.2) 42(890)

-62 Comparisons Comparisons density and snrvival proccsses ()[ the Parasa lepida

A few casεs of egg predation by Harmonia axyridis A total of 57 ， 804 and 248 cocoons were observed on (Pallas) ，a common ladybeetle ，were included as other T. seb 俳ra in 2005 ， 2006 and 2007 ，respectively. These miscellaneous miscellaneous deaths. Egg mortality was 43 .4%， 14.6% ， figures were 11. 4， 4.2 and 5.9 times greater than those and 38.6% on T. sebifera ，respectively ， in 2005 ， 2006 and on Q. m) 刊 inaefolia (5 ，193 ，and 42 ，respectively in 2005 ， 2007 ，which was greater than the corresponding 2006 and 2007) . mortality mortality on Q. myrsinaefolia ，15.7% ， 12.0% and 2l. 4% (P

Table2a 圃 Life tables of the second generation of p. lepida on 主 sebifera and Q. myrsinaefolia in 2005. 日ost plant 一一王子台企m Q. Myrsinaefolia No. No. of alive at 1¥ 0. of dying 1¥ 0. of alive al 1¥ 0. of dying Age Age class beginning of X Factors of Mx during X Mortality rate (%) beginning 01 X Factors of :V !x during X Mortality rate (%) X I¥ x (lx) MxF Mx ivlx/N どlω Nx (l x) MxF Mx エ1x/l¥ x' 1∞ Egg Egg 3079 (1ω0) 779 (1 ∞0) parasitoid parasitoid 467 15 .2 parasiloid 19 2.4 unknown unknown and unknown and miscellaneous miscellaneous 82 2.7 miscellaneous 29 3.7 Larva Larva 2630 (82 1. 7) 731 (938) unknown unknown and unknown and miscellaneous miscellaneous 2355 93 .1 miscellaneous 579 79.2 Cocoon Cocoon 175 (56.8) 152 (195 .1)

Table Table 2b. Life tables of the second generation of p. lepida 0n T sebifera and Q. myrsinaefolia in 2006. Host Host plant 7: seb ![e"" Q. Myrsinaefolia No. No. of alive at 1¥ 0. of dying 1¥ 0. of alive at l¥ o. of dying Age Age class beginning 01 X Factors of Mx during X Mortality rate (%) beginning 01 X Factors 01 :V !x during X lvI ortality rate (%) X Nx (l x) MxF Mx '.lx/ 1¥ど 100 l¥ x (l x) MxF Mx Mx/N どI∞ Egg Egg 21138 (1000) 3965 (1 000) parasitoid parasitoid 2581 12 .2 parasitoid 659 16.7 unknown unknown and unknown and miscellaneous miscellaneous 3747 17.7 miscellaneous 295 7.5 Larva Larva 14810 (7 ∞ 6) 3001 (758.8) unknown unknown and unknown and miscellaneous miscellaneous 14774 99.8 miscellaneous 2864 95.4 Cocoon Cocoon 36(17) 137 (34.6)

Table 2c. Life tables of the second generation of p. lepida on T sebifera and Q. myrsinaefolia in 2007 Host Host plant T. s坐生'ra 金必brsinaefolia

"0. "0. of ali 苛 eat 1¥ 0. 01 dying 1¥ 0. of alive at N 札 of dying Age Age class beginning of X Factors of Mx during X Ylortality rate (%) beginning of X Factors 01 Mx during X Mortality rate (%) x NxOx) MxF '.lx Mx/ I¥ど 100 Nx (l x) MxF Mx Ylx/N ど100 Egg Egg 11851 (1 0∞) 6917 (1 0ω) parasitoid parasitoid 3064 25.8 parasitoid 1002 14.5 unknown unknown and unknown and miscellaneOllS miscellaneOllS 3616 30.5 miscellaneous 1736 25 .1 Larva Larva 5181 (437.2) 4179 (ω4.2) unknown unknown and unknown and 5060 5060 97.7 3864 92.5 日}iscellancous miscellaneous Cocoon Cocoon 121

63 63 Sawada et αJ

2 .4% on Q. myrsinaefolia in 2005 maximally up to 25.8% On the other hand the enhanced larval survival on T. on T. sebifera in 2007 ，though the tendency was not sebifera may be ascribed at least partly to better consistent consistent between the two host plants. In contras t， nutritional quality of T. sebifera as the food resource. the the total egg mortality was slightly higher on T. Sawada et al. (2008) examined developmental sebifera sebifera (1 7.8% ，29.9% ，and 56.3% in 2005 ，2006 ，and performances of P. lepida larvae by providing them 2007 ， respectively) than on Q. myrsinaefolia (6.2% ， with either leaves of T. seb 俳ra or Q. myrsinaefolia ，and 24.1 24.1 %， and 39.6% in 2005 ，2006 and 2007 ，respectively) concluded that developmental performance was better

(p く0.0001 in all three years ，Fisher's exact test) on the former than on the latter in terms of both mass The total mortality during the larval stage was gain and developmental period. Further study is significantly significantly higher in the second generation than in necessary to confirm that the above tendencies are the the first generation on both hosts (P

T. T. sebifera; P く0.0001 and P<0.02 in 2006 and 2007 ， In contrast to the first generation ，life table data

respectively ，on Q. myr 百inaefolia ，Fisher's exact test). revealed that the cocoon density was higher on Q. The opposite trend was seen on Q. myrsin 何 foli αin 2005 myrsinaefolia than on T. sebifera in the second

(p く0.0001). The enhanced larval mortality in the generation in 2006 and 2007 ， or was virtually second generation was particularly evident on T equivalent between the two hosts in 2005. The field sebifera ，contrasting to the opposite trend in the first census detected no significant differences in cocoon generation. generation. A large number of larvae were found dead density in the second generation between the in in a typical wilted state with their prolegs clinging to deciduous and evergreen species based on data from leaf leaf petioles. These larvae were identified as being 404 trees of 51 plant species (Fig. 1). This was killed killed by nuclear polyhedrosis virus (NPV) because of exclusively because of substantially lower survival of the the presence of a large number of polyhedrosis in the larvae on T. sebifera than on Q. myrsinaefolia blood. blood. NPV is known also from another Limacodidae considering the fact that the egg density was rather moth Scopelodes contract ω，which has similar ecological higher on the former host (similar to the position in and life history properties (Aratake and Watanabe ， the first generation) (Fig. 2). Moreover ， it is 1973) 1973) . noteworthy that the larval mortality was particularly enhanced when the density of eggs (E) and larvae Factors Factors responsible for the host-related difference in (L) were higher ， as was observed on 工T. seb( ぴfera 出in

cocoon cocoon density 2006. This de 釘en 凶悶s引it 吋y

円g. 2 compares the cocoon density (C) ， the egg density 肝0ve 目r-compensation ，finally r・esulting in a lower density density (E) ， the egg survival (S (E) )， and larval cocoon density in the second generation in years of survival survival (S ( L)) between T. sebifera and Q. higher density of the first generation than in myrsinaefolia myrsinaefolia on the logarithmic scale. years (Table 2). A large number of larval deaths due In In the first generation ， the cocoon density was to NPV were observed ，particularly in years when the consistently consistently higher on T. sebifera than on Q. larval density was high ，though we could not identify myrsinaefolia ， the tendency of which agreed with the various mortality factors accurately. In genera l. results results of the 五eld observation based on data obtained infection of NPV spreads very rapidly as the host from 404 trees of 51 species (Fig. 1). The higher density increases ，and thus NPV is regarded as one of density density on T. sebifera than on Q. myrsinaefolia may be the critical factors to end outbreaks of moth larvae ascribed ascribed to the higher egg density and the higher (Stairs ， 1971). Studies on outbreaks of the gypsy moth larval larval survival ， as typically observed in 2005. In Lymantri αβ lmida Butler ，a major pest of fir forests ， contrast ， the higher egg survival on Q. myrsinaefolia ， revealed that most of the outbreaks ended due to the

being being consistently observed over the 3 years ，affected prevalent infection of NPV (Koyama and Katagiri ， host-related host-related differences in the cocoon density very 1959). In this contex t， further study is necessary to little little (Fig. 2). The higher egg density on T. seb 俳ra examine the transmission and infection mechanisms of may be due to the oviposition preference of P. lepida NPV to understand better the population dynamics of females females on the grounds that both plant species are P. lepida.

quite quite similar in the tree height ， shape and foliage area

-64 一 Comparisons Comparisons density ancl survival processcs of the Parasa lepid α

一一+-- T. sebtfera

凪・唱邑・- Q. myrsinaefolia 1 st Generation 2nd Generation 2.0 2.0 2.0 2.0

1.5 1.5 1.5 . • • 思 -・ 置喝畠層調膏F 酬' () () 1.0 、 1.0

b.O b.O 句 .3 .3 0.5 箇 0.5

0.0 0.0 de 0.0 園 -0.5 -0.5 一0.5 2005 2006 2007 2005 2006 2007

3.5 3.5 3.5

3.0 3.0 3.0 a はJ 2.5 2.5 • ，， b.O 。b.O ， _J 2.0 2.0 聞

1.5 1.5 1.5

1.0 1.0 1.0 2005 2006 2007 2005 2006 2007

(出)の nU nUK1v Ill1111「 じ...:;..----.. -:...:.ι 斗 ωoJ -~ι43 円 nu広 し U U 2005 2006 2007 2005 2006 2007

0.0 0.0 0.0

-0.5 -0.5 -0.5 -0.5 闘 〆イ合百九噌 _，....._ _，....._ -1ρ -1. 0 a 」 、、../ w (fJ (fJ -1.5 一1.5 b.O 。b.O

_J -2.0 司 2.0

-2.5 -2.5 一2.5

-3.0 -3.0 一3.0 2005 2006 2007 2005 2006 2007 Year Year

Fig. Fig. 2 Comparisons of the cocoon density (C). egg density (E). survival rate during egg stage (S (E)). and survival survival rate during larval stage (S (L)) of the Parasa lepid αbetween deciduous (Triadica seb 俳ra; straight lines with diamond symbols) and evergreen tree (Quercus myrsinaefi フlia; broken lines with square symbols) in the first (l eft- hand) hand) and second (right-hand) generation from 2005 to 2007.

-65 一 Sawada el αl

an out breaking population of Lymantria fumida Acknowledgements Butle r. J.J pn. For. Soc. 41 (1) : 4-10. (i n Japanesε) Miyata ， A. (1981) On Parasa lepida Cramer. of

We would like to thank Dr. C. Imai ，Osaka City Niho 6: 21- 23. (i n Japanese)

Institute Institute of Public Health and Environmental Sciences ， Nakano ，K. (2003) Distribution of blue striped nettle and D r. H. Tanaka ， Agricultura l. Food and grub ，Parasa lepida (Cramer) (Lepidoptera: Environmental Sciences Research Center of Osaka Limacodidae) ， in Kanto District. House and Prefecture ， for their valuable comments and Household lnsect Pest 24 : 61 62. (i n Japanese) discussions. discussions. Thanks are also due to anonymous Nishida ，S. ， Y. Araki ，and H. Sawada (2006) Seasonal referees referees for comments that improved the manuscrip t. population changes of thεblue striped nettle grub We also thank Y. Araki ，S. Nishid 呂， Y. Mizuno ， T. Kato ， moth Parasa lepida (Cramer). Ann. Rept. Kansai Pl. Y. Y. Hori ， S. Shimomura and M. Kida for their kind Prot. 48 : 115 - 117. (i nJ apanese) support support with the field survey Oda ，M. ，and 1. Hattori (198 1) The bluestriped (greenstriped) nettle grab ， Latoia lepida References (Cramer) :A new pest of Japanese persimmon. Plant Plant Protection 35 : 401 - 405. (i nJ apanese) Robinson ， G. S. ， P. R. Ackery ，1. ]. Kitching ， G. W. Aratake ，Y.， and H 目 watanabe (1973) A newly discovered

nuclear nuclear polyhedrosis of the small blackish cochlid ， Beccaloni ，and 1. M. Hernandez (2001) Hostplants of of the moth and butterfly caterpillars of the Scopelodes Scopelodes contracta Walker. Jpn 目 J. appl. Ent. Zool. 17 17 : 132 - 136. (in J apanese) Oriental Region. The Natural History Museum ，

Hirashima ， Y. (1989) A check list of Japanese insect London Entomological Entomological Laboratory ， Faculty of Agriculture ， Sawada ，H. ， Y. Masumoto ，and S. Nishida (2008) Life

Kyushu University ， Fukuoka. 1767 pp. table and survivorship curves of the blue 田 striped Jeyabalan ，D. ，and K. Murugan (1996) Impact of nettle grub moth Parasa lepida. Ann. Rept. K ω， lsai Pl. variation variation in foliar constituents of Mangifera indica Prot.50 ・155 - 157. (i nJ apanese) Linn. Linn. on consumption and digestion efficiency of Stairs ， G. R. (1971) Use of viruses for microbial control La toia lepida Cramer. lnd よExp. Biol. 34 : 472-474. of insects. In “ Microbial Control of lnsects and Mites"

Kalshoven ， 1. G. E. (1981) Pests of crops in lndonesia. (Burges ， H. D. and N. W. Hussey eds) ， pp. 97 (Revised (Revised and translated by P. A. van der Laan) 124 ，Academic Press ，London ，New York.

PT. PT. Ichtiar Baru ，Jakarta. 701pp. Yamazaki ， K.， T. Kitamoto ，and K. Nakatani (1994) Kapoor ，K. N. ， S. R. Dhamdhere ，and S. V. Dhamdhere Host plant selection of the blue-striped nettlεgrub (1985) (1985) Bionomics of the slug caterpillar ， Latoia moth Parasa lepida. 11. N α ture Study 40 : 43 46 lepida lepida (Cramer) (Lepidoptera: Limacodidae) on Japanese) mango. J. Entomol. Res. 9: 235 236 Zhang ， B. (1994) lndex of Economically lmportant Koyama ，R.， and K. Katagiri (1959) On the virus disease Lepidopter. αCAB 1nternationa l， UK of of Lymantriafumida Butler 1. On a virus epizootic in

-66 Comparisons Comparisons density and survival process 目。 f the Pαras μ lepi 向

落葉樹と常緑樹でのヒ日ヘリア 力、 Pa 悶 sa lepida (Cramer) の繭密麗と個体群 増殖過程の比較

沢田裕一 1) ・増本喜久 1 )・松本崇 2) .西国隆義 3) 1 )滋賀県立大学環境科学部生物資源管理学科 2 )京都大学大学院人間環境学研究科相関環境学専攻 3 )京都大学大学院農学研究科昆虫生態学研究室

2004~2007 年の 4 年間，滋賀県彦根市にある滋賀県立大学構内において， 36 穣 282 株の落葉樹と， 15 種 122 株の常 緑樹でヒロヘリアオイラガの繭密度を調査するとともに，落葉樹のナンキンハゼと常緑樹のシラカシで，生命表の作製 を含む詳細な個体群調査を行った.第 1 世代では，落葉樹の橋密度は常緑樹より有意に高いことが示され，また第 2 世 代では，落葉樹と常緑樹で繭密度に有意な差は認められなかった.ナンキンハゼとシラカシでの生命表調査の結果、第 I 世代の繭密度は落葉樹であるナンキンハゼで高し他方，第 2 世代の繭密度は常緑樹であるシラカシで高い傾向が認 められた.第 1 世代にナンキンハゼでの繭密度が高い理由として，卵密度が高いことと，幼虫期生存率が比較的高いこ とが重要だと考えられた.他方，第 2 世代では，ナンキンハゼ、での卵密度は，第 1 世代と向様，シラカシより高いにも かかわらず，幼虫期の死亡率が著しく高く，その結果，ナンキンハゼでの繭密度はシラカシより低い傾向を示した.ナ ンキンハゼでの幼虫期の死亡要因として，核多角体病ウイルス (NPV) の感染による死亡が重要だと考えられた.

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