cis-Verbenol - Journal of the Entomological Society of British Columbia

34
J. E NTOMOL. Soc.
BR IT. COL UMB IA
S8.
D ECEMBER.
199 1
cis- Verbenol: An aggregation pheromone for the mountain
pine beetle, Dendroctonus ponderosae Hopkins
(Coleoptera: Scolytidae)
DANIEL R. MILLER
CENT R E FOR PEST M ANAGE M E NT
DE P ART ME NT OF BIOLOG ICA L SC IENCES
S I MO N FR AS ER UN IVE RS IT Y
BURNA BY, BRITIS H C OL UM BI A V5A IS6 CANA DA
AN D
JE AN P. LAFO NT AINE
PH E RO T EC H INC. 7572 PRO(; R ESS W AY. RR 5
DE LTA, BRITIS H C OL UMBI A
V4G I E9 CANA DA
ABSTRACT
cis- Ve rbenol increased catc hes of male mo unta in pine bee tl es. Dendroctonus ponderosae
Hopk ins. to m ulti ple-funne l traps ba ited w it h myrcene and e.w-brev ico m in. cis-Verbenol had
no effec t o n the response of ma les to traps ba ited wit h myrcene. e.w-b rev icom in and
tralls-ve rbe no !. In contrast, cis-ve rbenol increased catc hes of fe ma le D . ponderosae to
se mi ochemi cal-ba ited traps irrespec ti ve of the abse nce o r presence of tralls-verbeno !. O ur
res ults demo nstrate th at cis-verbe nol is an agg regati o n phe romo ne fo r D. pOIlc/erosae and
th at the com bi na ti on of cis- andtralls-verbeno l e lici ts sex-specific responses .
Add iti ona l keywords: tralls-ve rbe nol. myrce ne. e.w-brevicomi n. sex-s pecificity.
INTRODUCTION
Vari o us studies on the use o f se mi oc hemi ca ls by the mo untain pi ne beetle, D endmctonus
p onderosae Hopkin s (Coleoptera: Scolytidae), including some that we re spec ificall y
aimed at determining the e ffec t of frans-ve rbeno l, in adve n antl y used frans-ve rbeno l contaminated with 6-20 % cis-ve rbeno l (Pitman 197 1: Billin gs ef o f. 1976; Ryke r and
Rud in sky 1982; Borden ef of. 1983: Conn ef 01. 1983). T he ro le of frans-verbeno l as a
pheromo ne for D. ponderosae has s ubsequentl y been veri fied with chemi cal purities
>97 % (Ryker and Rud in sky 1982: Li bbey ef a l . 1985: Borde n ef 01. 1987).
However, no attempt has been made to di sce rn the ro le of cis-verbeno l in the chemica l
eco logy of D . pondemsae and interpretation of studi es using contaminated tralls-verbeno l
must therefore be suspect. T he iss ue is of economi ca l im portance since D . ponderosae is
a major pest of lodge po le pine in the Pac ific northwest (Safranyik et o f. 1974; Furni ss and
Caro lin 1980). Semi ochemi cal- based manipul ati on of D . ponderosae has become a major
component of lodgepo le pine sil vicultu re in Briti sh Co lum bia (Borde n and Lacey 1985)
Due to production costs, the tree bait most commonl y used aga inst D . ponderosae contain s a 13:87 mi x of cis- and frans-ve rbeno l (Phero Tech Inc., Delta BC), together with
m yrcene and exo-brev icom in. DendmCfonus ponderosae uses m yrcene as a kai ro mone
(B illings et 01. 1976; Conn et 01. 1983; Libbey et 01. 1985; Borden et o f. 1987) and both
enanti omers of e.w-brev icomin as male-produced pheromones (Pitman et al . 1969;
Rudinsky ef 01. 1974; Pitman et of. 1978; Borden ef al . 1983; Li bbey ef al . 1985; Borde n
ef 01. 1987) .
O ur objecti ve was to demo nstrate that cis-ve rbeno l is an agg regati on pheromone for D.
ponderosae in stands o f lodgepo le pine. cis- Verbeno l is produced by D . ponderosae
(Pitman et al. 1969; Hughes 1973; Ryker and Rud insky 1982; Libbey et al. 1985 ; Pierce
ef 01. 1987; Hunt et al . 1989). Antennae of both sexes o f D. ponderosae are sensitive to
cis- and trans-verbeno l eq ua ll y (Whitehead 1986; Whitehead et 01. 1989). It is quite
probable, therefore, that cis-ve rbeno l is a pheromone fo r D. ponderosae. We tes ted the
J.
E NTOMOL.
Soc.
BRIT. COLLIMBI.·\ XX. D I:CI , ~lI l1-JC 199 1
3S
two foll ow ing hypotheses: I) cis-ve rbe no l should increase atlrac ti on of D. p Ollderosa e to
traps baited with myrce ne and e.w- brev icomin: and 2) cis- and Ilwls-verbenol should
ha ve an additi ve effec t on th e attrac ti on of D. p Ollderosac.
MATERIALS AND METHODS
c i .l- Verbe nol
was prepared by reducti on of S-( - )-ve rbenone by the alkoxy-substitut ed
lithium aluminum hydride method (Brow n and Deck 1965) and conce ntrated ill I 'au/(!.
l ra ll.\"- Verbe nol was prepared by subjectin g cis-ve rbeno l to ac id-catal ysed isomeri sati on
at 23 °C (Cooper cl a l. 1967) and purifi ed by fl as h chromatog raph y on silica gel (Still ('/
a l. 1978). Chemical and opti ca l purities of ve rbenol s were detennined by split. capill ary,
gas chromatog raph y (Hew letl Packard HP 5890 using a 30-m X 0.32- mm ID DB-I fu sed
sili ca co lumn ), before and aft er deri vati sati on to acetyl lactate diastereomers (Sl essor cl
a l. 1985). The chemica l puritics of c is- andlmlls-ve rbenol were 97 and 99%, respec ti veIy, whi Ie th e ch iral ratios were ide nt ica l at 83 % S -(-): 17% R -(+ ).
Verbe nol lures con sisted of po lyeth ylene, bubbl e-cap dev ices (Phero Tech [nc., Delta
BC) co ntainin g I J- butanedi ol so luti ons of cis- and Iralls-verbenol, res pectively. The
release rates of c is- and liwis-ve rbenol were approximately 3.38 and 2.58 mg/day at 2427 °C (determined by we ight loss). Phe ro Tec h Inc. (Delta BC) suppli ed the foll owin g
additi onal lures : I) (±)-e.w-b rev icomin (c hemical purity, 98 %) lamin ar lures; and 2)
l3-m yrcene (c hemi ca l purit y, 987r ) in cl osed, polyethylene, sc rew-cap bottles ( 15 mL).
The release rates of e.w-brev icomin and myrcene we re approx imately 0.0 I and 28 I
mg/day, respecti ve ly. al 24 °C (determined by collecti on of vo latiles on Porapak -Q for
e.w- brev icomin and by we ight loss for myrce ne).
Fort y, 8- unit, multi ple-funn el traps (Lindgren 1983) (Phero Tech Inc. , Delta BC ) were
se t in 10 repli cate grids 01' :2 x 2 in stands of mature lodgepole pine near Princeton Be.
G rids we re spaced at leas t 100 m apart. and traps were set 10-15 m apart within eac h
rep licate. Each trap was suspended betwee n trees by rope so that the top funn el of the trap
was 1. 3- 1.5 m above groun d. No trap was within 2 m of an y tree. All traps were set during
the peri od of 2 10 26 Seplember 1989. Trealmenl s we re randoml y ass igned within eac h
repli eale. Th e control Ireal menl consisted of myrce ne and e.w-brev icomin while the
remainder consisted of myrcene, e.w-brev icomin and one of the following: I) cis-ve rbenol: 2) lralls-verbenol: 3) cis- and IrallS-ve rbeno!. Sexes in subsamples (N=20) of
lured D . p OIll /CI'OS(lC we re de termined by di ssecti on and internal exami nati on of genitali a.
The data were analysed using the SAS stati sti cal package ve r. 5.0 (SA S In stitute Inc ..
Ca ry NC). For each sex. trap catc h data. transform ed by In (Y+ I), we re subjected to 3way AN OV A. usin g rep licate. cis-verbeno!. IUllls-verbeno l, and the interaction of ci sand IUllls-ve rbe no!. as model fac tors. Two orthogonal contrast s we re performed on each
data se t. comparing catches in tra ps bait ed with myrce ne and e.w- brevi comin again st
calches to traps baited wi th rn yrcenc. c.w -brev ico rnin and cis-verbenol and catches to the
co mbin ation of myrcene. e.w-brev icolllin an d lralls- vcrbenol aga inst catches to traps baited wilh all fou r component s.
RESULTS AND DISCUSSION
Both cis- and lralls-ve rbenol signi fica ntl y increased the catches of D. p o ndero sae to
se mi ochemi cal -baited fun ne l traps (Fi gs. I and 2). alth ough the effec t of cis-verbenol on
females was on ly weak ly signi ficant. There was a sig nifi cant interacti on between ci s- and
lralls-verbeno l on the ca pture of male D . IJO lideros(lc (Fi g. I). Catches of mal es in traps
ba it ed with myrce ne. c.w -brev ico min an dlrallS-verbe no l were not signifi cantl y different
from catches in traps bai led with all fou r component s (orth ogonal contra st. F( I .35 ).
P=O.750) . Catches of males in Ira ps baited with myrce ne, c.w-brev icomin and cis-ve rbe nol were signifi cantl y hi ghe r th an th ose in tra ps bail ed with myrce ne and c.ro-brev icomi n alone (orth ogonal cont rast. F( 1.35). P=O.004 ). In contrast. there was no interac ti on
betwee n cis- and Irolls-ve rbeno l on the catches of female D. p Oll derosoc (Fi g. 2).
36
J.
ENTOMOL.
Soc.
BRIT. COLUMBIA
88, DECEMBER, 1991
ANOVA
P
Source df
A
0.651
9
B
< 0.001
1
0.058
C
1
0.018
B*C
Error 26
M + eB
M + eB +cV
M + eB +tV
M + eB +cV+tV
o
20
40
Mean (+SE) percentage of males
captured per replicate
Figure I. The effec ts of cis- (cV) and/rans-verbeno l (tV) on the attraction of male D. ponderosaI'
to multiple-funnel traps baited with myrcene (M) and e.ro-brev icom in (eB) near Princeton Be from
2 to 26 September 1989 (n= I 0). Data were transformed by In(Y + I) and subjected to ANOV A
using the following model factors: replicate (A), cis-verbe nol treatment (B), tralls-verbenol treatment (e); and the interaction between cis- and frans-verbenol tre atments (B*e). The total number
of males caught was 2303.
ANOVA
Source df
P
A
0.001
9
B
< 0.001
1
0.089
C
1
0.984
B*C
Error 26
M + eB
M + eB +cV
M + eB +tV
M + eB +cV+tV
20
40
Mean (+SE) percentage of
females captured per replicate
0
Figure 2. The effects of cis- (cV) and fralls -verbe nol (tV) on the attraction of female D. plIllderf)s(fe
to mutiple-funne! traps baited with myrcene (M) and e.lO-brevicomin (eB) near Princeton Be from
2 to 26 September 1989 (n= I0). Data were transfollll ed by In(Y + I) and subjected to ANOV A using
the following mode! factors: replicate (A), cis-verbeno! treatment (B) , lralls-verbenol treatment (e).
and the interaction between cis- and lralls-ve rbenol treatm ents (B*e). The total nlllnber of females
caught was 5303.
Our results demonstrate that cis-ve rbenol is an agg regation pheromone for D. ponderosae. It is produced by female D. ponderosaI' (Pi tman 1'[ al. 1969; Hughes [973;
Ryker and Rudinsky 1982: Libbey ef at. 1985; Pierce ef at. 1987) and is aTtractive to both
sexes (Figs. I and 2). Interpretations of results from previous studies that used [rans-verbenol, with chemical purities less th an 97 %, shou ld consider the effect of cis-verbena!,
and the possible interactions of cis-verbenol with other treatments.
Our results further show that c is- and fralls-verbenol have an addi tive effect on the
aTtraction of female D. ponderosa£' but not on male D. ponderosaC'. The interaction
J.
ENT()~ 1 0L.
Soc. BRIT. COLIIMHI,\ R8. DITEMI1EK. 19lJ I
37
betwee n the ve rbe nols res ulted in sex-s pec ific responses; males and females res ponded
differen tl y to cis- and lrans-verbe no l separate ly than to the combination of verbe no ls
(Figs . I and 2). These sex-s pecific res ponses ma y be a function of e ither the presence of
bo th ve rbenols toge ther or of the rati o of verbenols. The rati o of cis- and lrans-verbe nol
fo ll ow in g a ut oxida ti o n o f a-pi ne ne ran ges from 29:7 1 to 20:80 (Hunt el 01. 1989) .
Axen ica ll y-rea red D . pone/erosoe produce verbenol with a cis: lrans ratio o f 14:86 whe n
ex posed to a-p ine ne odors w hile w ild beetl es produce a ratio o f 2:98 ( Hunt el al. 1989).
Regardl ess of the mode of spec ific ity, both cis- and lrallS-verbe no l are required to
ma ximi se the att rac ti on o f female D . ponderosae. Since fe mal es initiate attacks on trees
(S afran yik cl 01. 1974), it is critical that tree baits used in silvi c ultura l prac ti ces to control
populations o f D. ponderosae contain both phe ro mo nes. Fortunately the bait c urrentl y
e mployed ope rationa ll y for controlling D . ponderosoe contains both cis- and IIwls-ve rbe nol at a ratio of 13:87 (Phero Tech In c., Delta BC), we ll within the range of o bserv ed
production rati os.
ACKNOWLEDGEMENTS
We th a nk T.C Bak er. J.H. Bo rden , B.S. Lindg re n and three anonymous revi ewers fo r
c ritica l rev iews of the manu sc ript. Ass istance in the manufac ture of re lease dev ices was
kindly provided by Phe ro T ech Inc ., Delta BC Vouc he r specimens of D . ponderosae
ha ve been de posi ted at the Entomology Muse um at Simon Fraser Univ e rsity, BUl11aby
BC This researc h was suppo rted in part by the Natural Sciences and Engineering
Research Counci I of Ca nada (Operating Grant No. A3881 and Strategic Grant No.
G 161 I ). and the Sc ience Co un c il of British Columbia IGrant No . I (RC 14- 16) I.
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Melanehra piela (Harris) (Lepidoptera: Noctuidae),
a cutworm new to British Columbia
SHEILA M. FITZPATRIC K and J AMES T. TROUBRIDGE'
AGRICU LTURE CAN ADA RES EARCH ST ATION.
6660 N.W. M A RI NE DRIV E, VANCOU VER, R. C .. CANA DA V6T lX2
I. ORDER OF AUTHORS DECIDED RY TOSS OF A COIN.
He re we report the occurrence o f the zebra caterpill a r. Me/all chra piChl (Harri s) as a
mino r pest o f comme rc ia l c ranbe rries. Vaccinillm macrocarpol1 Ail.. in Lang ley and Pitt
Meadows. Briti sh Columbi a, during the summe r of 199 1. In the fie ld . zebra cate rpill ars
ate th e g row ing tips of c ranbe rry runne rs and up rig hts. In the labo ratory, larvae prefe rred
s ucc ul e nt cra nbe rry ti ss ue. con suming mature leaves o nl y if no ne w gro wth rema ined. In
the fie ld and labo ra to ry. la rvae a lso consumed the fo li age of dicoty ledonous weeds s uch
as c utleaf bl ackbe rry, Ruhus /acillialUs Willd ., wes te rn S t. John's wo n , Hypericumformoslim Humboldt, ma rsh St. John's wort. Triadellllm I'irgillieum L.. a nd W atson's w ill ow
herb. Epi/o/Jium walsollii Barbey. In easte rn Canada. ze bra cate rpill ars have been repo rted to feed o n a wide va ri ety of fruit. vege tabl e, and legumino us fo rage crops (Be irne.
1971 ).
Earl y records of ze bra cate rpill ar infestatio ns in Briti sh Co lum bia (Coc kl e, 19 11 ;
Middle ton. 191 3) ac tua ll y refe rred to Mam estra calladellSis Smith. now conside red a synonym of Lacanobia neI'Gdae (G rote) . In Canada, the ze bra cate rpill ar, M. piC/a. occ urs
from the Atlantic coast. west to the foo thill s of the Rocky Mo unta in s. whereas in the
U. S.A. its range ex tend s further west into Ca lifo rni a. Oregon . and W as hington . T he re are
no spec ime ns of M . pieta from B.C. in the Canadi an Nationa l Co ll ection . the Royal
Briti sh Co lumbi a Mu seum , or the S pe ncer Collecti o n, Uni ve rsity of Briti sh Co lumbi a,
no r does M. pieta appear o n li sts of B. C. fauna (e.g. Ll ewe ll yn Jo nes. 195 1). Recent
reports of M. pieta on straw berries . Fraga ria x ananassa Duch .. in 198 1. hi g hbu sh bluebe rri es. Vaec iniul11 corymhosum L.. in 198 3 (Be lto n, 1988) . and corn . 'Lea l11avs L. . in
1990 (Philip. 199 1) in B. C. probabl y re fe r to thi s spec ies. Since the ze bra caterpill ar has
prev io us ly been fo und ve ry cl ose to the B.C. bo rde r in W as hin gto n State , (To nas ke t. 40
km south of Osoyoos. B.C.: Pu ya llu p. 55 km south of Seattle). we be li eve that its prese nce in B. C. represe nts a recent range ex te nsio n ra the r than an introd uction .