Variation in the natural termite resistance of teak (Tectona grandis Linn. fil.) wood as a function of tree age

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1 Ann. For. Si. 65 (8) 78 INRA, EDP Sienes, 8 DOI: 1.151/forest:847 Aville online t: Originl rtile Vrition in the nturl termite resistne of tek (Teton grnis Linn. fil.) woo s funtion of tree ge Gnis Lukmnru 1,2 *,KoetsuTkhshi 3 1 Deprtment of Forest Prout Tehnology, Fulty of Forestry, Gjh M University, Jogj 55281, Inonesi 2 Unite Grute Shool of Agriulturl Siene Iwte University, Moriok -855, Jpn 3 Deprtment of Bioenvironment, Fulty of Agriulture, Ymgt University, Tsuruok , Jpn (Reeive 12 Ferury 8; epte 6 June 8) Keywors: Teton grnis / tree ge / termite resistne / extrtive ontent / olor Mots-lés : Teton grnis / âge e l rre / résistne ux termites / ontenu e l extrit / ouleur Astrt Tree ge is one of the most importnt ftors to ffet the nturl urility of woo. The purpose of this stuy ws to etermine the nturl termite resistne of hertwoo n spwoo of tek (Teton grnis Linn. fil.) for trees ge 8, 3 n 51 yers. Retiulitermes spertus Kole ws employe s test termite using no-hoie feeing metho. The hertwoo n spwoo of ll of the trees teste exhiite ntitermiti tivity. Bse on the men mss loss ue to termite tivity, the spwoo n hertwoo regions of 8-yer-ol trees re the most suseptile to termites while the hertwoo regions of the 3-yer-ol trees showe termite resistne similr to the termite resistne of 51-yer-ol trees. The mss loss is moertely orrelte with n-hexne extrtive ontent, totl extrtive ontent, rightness n reness of the woo. Résumé Effet e l âge e l rre sur l résistne nturelle u ois e tek (Teton grnis Linn. fil.) ux termites. L âge e l rre est un es fteurs les plus importnts e l urilité u ois. Le propos e ette étue étit e éterminer l résistne nturelle u ois e œur et e l uier e tek (Teton grnis Linn. fil.) ux termites, pour es rres âgés e 8, 3 et 51 ns. Retiulitermes spertus Kole été utilisé omme termite test ns un essi limenttion sns hoix. Le ois e œur et l uier e tous les rres ont été testés pour leur tivité nti-termite. En se snt sur l perte moyenne e msse e ois résultnt es tivités es termites, l uier et le ois e œur es rres e 8 ns se sont révélés les plus sensiles, lors que le ois e œur es rres e 3 ns montré une résistne ux termites semlle à elle es rres e 51 ns. L perte e msse étit moérément orrélée u ontenu e l extrit n-hexne, à elui e l extrit totl, insi qu à l rillne et à l rougeur u ois. 1. INTRODUCTION Tek (Teton grnis L. fil.) is the prinipl ommeril timer in Inonesi, prtiulrly on the isln of Jv. Despite the existene of tek plnttions mnge y the stte-owne ompny Perum Perhutni whih overs h in Jv, high emn from the woo inustries hs rete shortge in the supply of rw mteril. In orer to meet this emn, n inrese in the quntity of tek proue in hutn rkyt (hutn = forest, rkyt = ommunity) or frmln hs ourre. Aoring to the Ministry of Forestry of Inonesi, hutn rkyt is efine s forest grown on ln with ownership or other rights (Deprtemen Kehutnn, 1995). * Corresponing uthor: gnisrem@lyos.om Contrry to the prtie opte y Perhutni whih employs felling yle of 6 yers or more, most the frmln stns re fouse on otining short- to meium-term return on their efforts y hrvesting younger trees. The owners ommonly ut their trees when they reh n ge of to 3 yers. Conerns hve een rise over the qulity of the woo otine from suh younger trees. Logs from these plnttions will hve lrge proportion of spwoo n immture woo, whose properties my iffer from those of oler trees. With tek, the mjor onerns re with regr to urility n olor. In terms of urility, tek is vlue for its nturl termite resistne properties. Ngee et l. (4) reporte tek s less preferre speies ginst ntive pest Coptotermes, Artile pulishe y EDP Sienes

2 Ann. For. Si. 65 (8) 78 G. Lukmnru n K. Tkhshi Tle I. Desription of the smpling n sites. Ftor 8 yer-ol 3 yer-ol 51 yer- ol Origin Site lotion (provine) Numer of smples Altitue (m) Est longitue South ltitue Soil type Annul rinfll-rnge (mm) Temperture rnge C Reltive humiity Men imeter (m) Men hertwoo proportion (%) Men spwoo thikness (m) frmln stns Gunungkiul (Jogj) 5(treeno1to5) lk lreous, lom frmln stns Kulonprogo (Jogj) 4(treeno6to9) lluvil, lomy sn Perhutni plnttion Rnultung (Centrl Jv) 5 (tree no 1 to 14) humous mrgliti, lomy sn Spwoo zone Color n termite test smpling Outer spwoo Extrtive ontent smpling Inner spwoo Outer hertwoo Hertwoo zone Mile hertwoo Inner hertwoo Figure 1. Smpling position on ross-setion of tek trunk. (1) Miroertotermes, Gloitermes, Mrotermes termites in preferene test. It hs prolems, however, suh s its spwoo with referene to the ry woo termite inger-inger (Neotermes tetone Dmm.) (Suiynto, 1995). Tek woo ws lso prove to e nturlly resistnt ginst non-ntive termites (Beker, 1961). There is no out tht this vntge n e ttriute to extrtives. Tree ge, extrtiveontent n ril position hve een reportes ffeting the nturl termite resistnes (D Cost et l., 1958; 1961; Rumn et l., 1967). The ojet of this stuy is to etermine the nturl termite resistne of hertwoo n spwoo of plnttion grown tek. Smples hve een exmine for 8, 3 n 51 yers ol. A ftoril esign ws use to investigte the effets n intertion of tree ge n ril position on termite resistne properties. Anlysis of the ontent of the extrtives n the olor of the woo were inlue in the stuy euse these ftors re likelytohveneffet of the urility of the woo. OS: outer spwoo (..5 m from the rk), IS: inner spwoo (..5 m from the hertwoo-spwoo ounry), OH: outer hertwoo (..5 m from the hertwoo-spwoo ounry), MH: mile hertwoo, IH: inner hertwoo (. 2 m from the pith). With the limite mount of suitle mteril ville, the MH n IH zones in the 8-yer-ol iss n the IS zone in the 51-yerol iss were exlue. Eh prt from two opposing rii ws onverte into woo mel y rilling. It ws then omine to form single smple in orer to minimize vritions etween rii. The mel smples were then groun to size of 4 6 mesh for etermintion of extrtive ontent. For the termite resistne test n olor properties, loks. 5. (L).8 (T).8 (R) m mthing smples for extrtive ontent etermintion (Fig. 1), were strippe from eh prt n rius. The loks were then rie t 1 Cfor3h,fter whih they were oole n weighe. 2. MATERIALS AND METHOD 2.1. Tree smpling Woo smples from soun 8 n 3-yer-ol trees were otine rnomly from the frmln stns n smples from the 51 yer-ol trees were otine from the Perhutni plnttion. The onition of the sites n tree hrteristis re esrie in Tle I.Diss5min thikness from the felle trees were ut t imeter rest height. The test speimens were tken suessively from spwoo to hertwoo, n ivie into five setions imetrilly (Fig. 1): 2.2. Termite resistne test Termite speies The suterrnen termite Retiulitermes spertus Kole, one of the most woo mging speies in Jpn, ws use in this work. Pine (Pinus ensiflor Sie. et Zu.) logs ontining termites were ollete in the mountin re ner Tsuruok, Ymgt n mintine in n environmentl hmer t 25 C, 75% RH in the lortory until initition of the test. Helthy worker termites were tken from these logs n expose to the woo loks. 78p2

3 Vrition in the nturl termite resistne of tek s funtion of tree ge Ann. For. Si. 65 (8) No-hoie test on woo loks For eh test, n ir-rie woo lok (moisture ontent 1 12%) ws inserte into plsti up (5. m 6. m), n ple on g of sterile sn. The sn ws moistene with istille wter regulrly to retin onstnt reltive humiity. Fifty worker termites were e to eh up. Inlue in the tests for omprtive purposes were ontrols of suseptile pine spwoo loks n strvtion ontrols ontining only sn sustrte. Three replites were mesure for eh smple, for totl of 171 oservtions. The ups were ple in the environmentl hmer for two weeks. No ttempt ws me to remove e termites from the up uring the tril perio. To mesure the termitiil tivity, surviving termites were ounte in first week n t the en of oservtion. The mss loss ws etermine to quntify the extent of the termite ttk on the woo. A sujetive evlution ws performe, wherey ll prts teste were lssifie into the following four lsses of resistne oring to their men mss loss vlues (MML, in mg). Clssifitions were s follows: highly resistnt ( < MML 5), resistnt (5 < MML 1), moertely resistnt (1 < MML 15), n non resistnt (15 < MML) Extrtive ontent The extrtive ontent ws etermine for 2 g (se on oven ry weight) woo mel using Soxhlet pprtus. Extrtions were onute using 6-h sequene of n-hexne, ethyl ette (EtOA) n methnol (MeOH). The solvents were onentrte in rotry film evportor, rie, n weighe to etermine the n-hexne, EtOA, n MeOH extrtive ontent se on oven ry woo mel (m/m). The totl extrtive ontent ws lulte y etermining the sum of ll extrtive ontents Color mesurement A portle spetrophotometer NF777 (Nippon Denshoku In. Co Lt.) with imeter opening of 6. mm, illuminnt A n tungsten hlogen light soure ws use. Perentge of refletne t ws ollete t nm intervls over the visile spetrum (4 7 nm). Color mesurements were tken for ir-rie termite woo lok test mentione ove. This ws performe efore initition of the ntitermite test. The olor prmeters were mesure in the mile of the tngentil fe (jent to mel smple) of eh smple. Three mesurements were me for eh smple n the verge vlues of the mesurements were lulte s the ifferent olor prmeters, esignte L*, *, n *. L* esries rightness (long rightness xis where 1 = white or totl rightness; n = lk or rkness) of olor. The vlue * esries the reness (long the X xis re (+) to green ( )), n the vlue * esries the yellowness (long the Y xis yellow (+) to lue ( )) Sttistil nlysis The effets of tree ge n ril position on survivl rte n mss loss were lulte y nlysis of vrine (ANOVA) GLM proeures. The effets were tken into ount only when signifint t the 95% level using Type III Sums of Squres. The termite survivl rtes (perentges) were trnsforme to r sine for nlysis Survivl rte(%) Survivl rte (%) Pine ontrol Strvtion ontrol Tree ge () Ril position () Figure 2. Survivl rte ginst Retiulitermes spertus on one-week oservtion of tekwoo y tree ge n ril position. Men of 5 trees (8- n 51 yer-ol) n 4 trees (3-yer-ol), with the stnr evition error r. The sme letters on the sme grphi re not sttistilly ifferent t P <.5 y Dunn s test. Pine n strvtion ontrol re inlue for the purpose of omprison. OS = Outer spwoo, IS = inner spwoo, OH = outer hertwoo, MH = mile hertwoo, IH = inner hertwoo. ut were presente s untrnsforme vlues to filitte interprettion. Mens of extrtive ontent n olor mesurement were teste y One-wy ANOVA. A Dunn test for multiple omprisons ws use to show whih group mens iffer. A Person orreltion nlysis ws employe for termite resistne prmeters, extrtive ontents n woo olor properties. All sttistis were performe with SPSS 1. softwre. 3. RESULTS AND DISCUSSION 3.1. Termite resistne Survivl rte The ANOVA of men survivl rte in the first week inites tht there is no signifint tree ge n ril position intertion (p =.8), while the effets of tree ge (p =.11) n ril position (p =.2) re signifint. Comprisons mong tree ge revel tht the survivl rte ereses signifintly with tree ge (Fig. 2). Close exmintion of the men vlues within ril position revels survivl rte etween the spwoo (69 77%) n hertwoo region (5 56%) re signifintly ifferent (Fig. 2). The intertion etween tree ge 78p3

4 Ann. For. Si. 65 (8) 78 G. Lukmnru n K. Tkhshi Survivl rte (%) Mss loss (mg) Ril position () Ril position 8-yer-ol 3-yer-ol 51-yer-ol () Figure 3. Survivl rte n mss loss ginst Retiulitermes spertus on 2-week oservtion of tekwoo y tree ge n ril position. Men of 5 trees (8- n 51 yer-ol) n 4 trees (3-yer-ol), with the stnr evition error r. Mens survivl rte of pine n strvtion ontrol were ± 2.3 n 16.6 ± 13.3%, respetively. Men mss loss of pine ontrol ws ± 5.69 mg. The sme letters on the sme grphi re not sttistilly ifferent t P <.5 y Dunn s test. OS = Outer spwoo, IS = inner spwoo, OH = Outer hertwoo, MH = mile hertwoo, IH = inner hertwoo. n ril position is highly signifint (p =.2) in regrs to the men of survivl in the seon week. The survivl rte mens in the seon week re shown in Figure 3. The highest surviving termite levels re otine t the OS n IS of 8-yer-ol trees (47 55%). No signifint ifferenes oul e oserve etween the three tree ge groups in the hertwoo. The men survivl rte vlue of termites uner omplete strvtion ontrol onition is 16% fter the 2-week test perio. The survivl rte vlue of the pine ontrol is 88%. Bse on these results, the nturl termitiil tivity of tek woo is not thought to e ute. This onfirms erlier reports (D Cost et l., 1958, Rumn et l., 1967), whih emonstrte tht tek woo is not toxi ut merely eters the suterrnen Coptotermes lteus Frogg. n Nsutitermes exitiosus Hill termites. However, the survivl rtes mesure in this work for the termites expose to tek smples re lower thn in those reports. These ifferenes of survivl rtes my e ue to the use of ifferent termite speies in this experiment. In previous stuy, Beker (1961) oserve tht the resistne n suseptiility of the woo speies vries with every termite teste. Ngee et l. (4) suggeste ifferentil feeing preferene mong Coptotermes speies, s well s towrs woo speies from ifferent geogrphil lolities. Thus, the use of ntive pests in iossy test, e.g. the most ggressive Coptotermes urvignthus Holmgren termites, woul provie more informtion with regr to the nturl resistne of tek Mss loss The ANOVA of mss loss shows signifint tree ge n ril position intertion (p <.1), initing tht the effet of tree ge vrie with the ril position. Bse on MML t (Fig. 3), hertwoo of ll ges flls into resistnt n highly resistnt lsses wheres spwoo flls into lsses rnging from resistnt to non-resistnt. The mss loss in the OH tens to erese with tree ge, the reltive mss loss in the OH of 51 yer-ol trees (1.37 mg, highly resistnt lss) is signifintly lower when ompre to those of 8 yer-ol trees (7.45 mg, resistnt lss). While the IH region is foun to e less resistnt thn the OH or MH region, the ANOVA of mss loss etween the ril prt in the hertwoo of oth the 3 n 51-yer-ol groups oes not vry signifintly. The mss loss of the OS ereses signifintly with tree ge. The OS of 8 yer-ol trees is lssifie s non-resistnt (MML mg) while the OS of 51-yer-ol is lssifie s resistnt (MML 6.3 mg). The level of tivity of the OS of 51-yer-ol trees is even omprle to tht of the OH of 8-yer-ol trees. Compre to the ontrol pine smple (MML mg), however, the OS of 8 yer-ol trees exhiits higher ntifeent tivity. The mss loss in the IS (7.84 mg) re signifintly lower thn those in the OS (14.52 mg) of 3-yer-ol trees, ut similr tren is not oserve in the spwoo of the 8-yer-ol groups. These results seem to e in greement with previous stuies (D Cost et l., 1958; 1961; Rumn et l., 1967), in tht n inrese in nturl termite resistne with tree ge in the hertwoo is eviene. Similr tenenies hve lso een note in stuies of the ey resistne of tek (Bht n Florene, 3; D Cost et l., 1958, 1961; Hupt et l., 3; Rumn et l., 1967). The otine results show the hertwoo of 3- yer-ol trees hieves similr termite resistne level to 51- yer-ol trees. This is n enourging result onsiering the reent inrese of young trees utiliztion. On the other hn, the termite suseptiility in the spwoo must e tken into onsiertion, sine the perentge of spwoo is reltively high in trees younger thn 51 yers. The stnr evition of the mss loss vlues is lrge even in the sme group. This inites tht woo smples of the sme ge group n ril prt my elong to ifferent lsses of ntitermiti resistne. A goo exmple of this is the OH of 3-yer-ol tree no 9. This is lssifie s resistnt while the OH of 3-yer-ol tree no 7 is lssifie s moertely resistnt (t not shown). With regr to ey resistne, signifint vritions mong tree smples re lso foun in 5- yer-ol tek (Bht n Florene, 3). Differenes in termite survivl n mss loss re lso foun mong the ontrol group initing the possily tht slight ifferenes in test onitions ourre etween trils. 78p4

5 Vrition in the nturl termite resistne of tek s funtion of tree ge Ann. For. Si. 65 (8) 78 Hexne extrtive ontent (% EtOA extrtive ontent (%) Ril position Ril position () () MeOH extrtive ontent (% Ril position Totl extrtive ontent (%) ef e ef f ef ef Ril position 8-yer-ol 3-yer-ol 51-yer-ol ef () () Figure 4. n-hexne, EtOA, MeOH, n totl extrtive ontent (% oven rie mss m/m) of tekwoo y tree ge n ril position. Men of 5 trees (8- n 51 yer-ol) n 4 trees (3-yer-ol), with the stnr evition error r. The sme letters on the sme grphi re not sttistilly ifferent t P <.5 y Dunn s test. OS = Outer spwoo, IS = inner spwoo, OH = Outer hertwoo, MH = mile hertwoo, IH = inner hertwoo Extrtive ontents The n-hexne extrtive ontent (NHEC) etermintions re shown in Figure 4. By ANOVA, NHEC levels in the OH of 3 n 51 yer-ol trees (4.36 n 4.52% respetively) re signifintly higher ompre to those of 8-yer-ol trees (1.74%). In ril iretion, NHEC levels in the IH lso iffer signifintly from those in the OH n MH region. The NHEC levels in the OS region ten to inrese with tree ge. The mximum levels re otine in the OS of 51-yer-ol trees (1.52%), the ifferene is signifint from the minimum levels in the OS of 8-yer-ol trees (.53%). The NHEC levels etween IS n OS oes not iffer signifintly. The EtOA extrtive ontent (EEC) etermintions re presente in Figure 4. By ANOVA, the vrition mong the ifferent tree ge in the OS n OH region is not signifint. The ANOVA revels signifint ifferenes re foun for ril iretion of 3-yer-ol trees, whih the EEC levels in the OS n IS (.36 n.41%, respetively) re lower ompre to those in the OH region (1.69%). The EEC level vrition mong the ifferent ril iretion in the hertwoo is not signifint. The MeOH extrtive ontent (MEC) etermintions re isplye in Figure 4. In the spwoo, the OS of 51-yerol trees shows the highest MEC level (4.41%), signifintly higher in omprison to the lowest levels in the OS n IS of 3 yer-ol groups (2.16 n 2.9%). In the hertwoo, even though the mximum MEC levels re otine in the OH of 8 yer-ol trees (4.7%), the ifferene is not sttistilly signifint in omprison to the lower mount in the OH of 3 n 51-yer-ol groups (2.59 n 2.96%, respetively). Systemti ifferenes mong the ifferent ril iretion in the hertwoo re not foun. The minimum MEC levels in the hertwoo re otine in the MH n IH of 51-yer-ol trees (2.19 n 2.5%). Within ll ge groups, totl extrtive ontent (TEC) inreses from the pith until the OH n then ereses towrs the OS (Fig. 4). The ril istriution pttern of the ontent of the extrtives through spwoo n hertwoo orrespons to the shemes generlly reporte y woo hemists. A omprison etween the three tree ges inites n inrese of TEC levels in OS n OH. In the spwoo, the mximum TEC levels re otine in the OS of 51 yer-ol trees (6.78%), whih is signifintly higher thn those of the 8 n 3-yerol groups (4.15 n 3.53%, respetively). TEC levels in the IS re higher thn in the OS of 8 n 3-yer-ol trees, however, n ANOVA shows tht this is not sttistilly signifint. The ANOVA lso revels tht TEC levels in the OH of 51 n 3-yer-ol trees (9.17 n 8.53%) re sttistilly ifferent from those in the 8-yer ol trees (7.15%). TEC inreses signifintly from the IH towr OH of 51-yer-ol trees, ut 78p5

6 Ann. For. Si. 65 (8) 78 G. Lukmnru n K. Tkhshi without sttistil signifine in 3-yer-ol trees. The pttern of TEC with tree ge is in greement with erlier stuies y D Cost et l. (1958) n Nrynmurti et l. (1962). The orresponing vlues of TEC in this stuy re slightly higher thn those reporte y D Cost et l. (1958), ut lower thn those reporte y Nrynmurti et l. (1962),nBhtetl. (5). EtOA, moertely polr solvent, remove the lest extrtives while n-hexne, the lest polr solvent or MeOH, the most polr solvent remove the most extrtives in mnner epening upon the prt of the woo. Spwoo is generlly foun to ontin more methnol extrtives in ll ge groups. This pttern is lso oserve in the OH of 8-yer-ol trees n the IH of 51-yer-ol trees. This signifintly inrese of NHEC n TEC levels from IH to OH of 51- yer-ol trees, s well s, in the OH from 8 to 51-yer-ol groups inites the inresing ontent of TEC in the hertwoo is minly ttriute to n inrese of NHEC level. The teneny of NHEC n MEC in this stuy is in line with the teneny reporte in Nrynmurti et l. (1962), who oserve the mximum MEC level is foun in the OH of 1-yer-ol tree whilst mximum ether extrtive ontent level is foun in the OH of 62-yer-ol tek tree. These grients hve een interprete to inite tht onversion of polr ompouns to less polr ompouns inreses with time in the hertwoo of growing trees. The t suggest tht trnsformtion of juvenile woo into more mture woo is hrterize y signifint inrese in the mount of less polr extrtives. By the time given tree is 3 yers ol, reltively lrge proportion of less polr extrtives is otine in the extrtive ontent of the hertwoo region Color properties L* mesurements * mesurements * mesurements Ril position () h e f Ril position ef () e f Ril position ef ef e gh ef ef g For spwoo n hertwoo region, the rightness inex (L*) rnges from 73 to 77 n 54 to 6, respetively (Fig. 5). The ANOVA results show tht the OS in 51 yer-ol-trees trees (73.72) give signifintly rker olor thn those in 8 n 3-yer-ol trees (76.65 n 76.9 respetively). The rightness level tens to erese from OS to IS, with sttistil signifine in 3-yer-ol trees. The OH in 8 n 51-yer-ol trees (54.39 n 53.6, respetively) gives signifintly rker olor thn those in 3 yer-ol trees (6.57). Systemti ifferenes mong the ifferent ril iretion in the hertwoo re etete in 51-yer-ol trees, whih the rightness inex signifintly ereses from IH (58.32) to OH (53.6). The reness inex (*) of the spwoo n hertwoo region rnges from 2 to 3 n 4 to 6, respetively (Fig. 5). The mximum reness inex in the OS (3.94) re mesure in 51 yer-ol trees, the ifferene is sttistilly signifint in omprison to the lower mount t the OS of 8 n 3-yerol groups (2.97 n 3.5, respetively). The reness inex in the OH flututes with tree ge; the signifint men mximum reness inex is etete in the OH of 8-yer-ol trees (6.66), wheres the minimum inex is foun in 3-yer-ol trees (4.69). A ril ifferene is oserve in the hertwoo of 51-yer-ol trees, whih reness levels in the MH n IH 8-yer-ol 3-yer-ol 51-yer-ol () Figure 5. Color properties in L* (rightness), * (reness) n * (yellowness) of tekwoo y tree ge n ril position. Men of 5 trees (8- n 51 yer-ol) n 4 trees (3-yer-ol), with the stnr evition error r. The sme letters on the sme grphi re not sttistilly ifferent t P <.5 y Dunn s test. OS = outer spwoo, IS = inner spwoo, OH = Outer hertwoo, MH = mile hertwoo, IH = inner hertwoo. (6.6 n 6.11, respetively) give signifintly higher vlues thn those in the OH region (5.25). The yellowness inex (*) of the spwoo n hertwoo region rnges pproximtely from 22 to 25 n 24 to 26, respetively (Fig. 5). The ANOVA revels no signifint ifferene in the OS etween the groups. The highest yellowness level in the spwoo is etete in the IS of 3-yer-ol trees (25.31). A signifintly higher yellowness inex is mesure in the OH of 3 yer-ol trees (26.67) s ompre to the OH of 8 n 51 yer-ol trees (25.46 n 24.5, respetively). For oth 3 n 51 yer-ol groups, no signifint ifferenes re oserve etween ril prts in the hertwoo. 78p6

7 Vrition in the nturl termite resistne of tek s funtion of tree ge Ann. For. Si. 65 (8) 78 Tle II. Person orreltion oeffiients (r) for the termite resistne prmeters, extrtive ontents n olor properties. Prmeters Survivl rte in the first week Survivl rte in the seon week Mss loss n-hexne extrtive ontent.42**.34*.58** EtOA extrtive ontent.49**.34*.49** MeOH extrtive ontent Totl extrtive ontent.6.3*.51** L*.62**.45**.62** *.68**.45**.64** *.32*.8.31** ** Signifint t 1 % level, * signifint t 5 % level. Kokutse et l. (6) reporte the mximum reness vlue in the hertwoo is etete in the OH re, whih iffers from the present results, however, the pttern of rightness n yellowness vlue is in greement. The orresponing vlues of rightness n yellowness in the hertwoo in this stuy re slightly higher thn previously reporte, while the reness vlues re lower thn those of Inin tekwoo (Bht et l., 5) n Togolese tekwoo (Kokutse et l., 6). The ANOVA revels tht the olor inex vlues in the hertwoo of 8-yerol trees re lmost similr to those of 51-yer-ol trees. This is n unexpete oservtion euse of the generl ssumption tht the hertwoo of younger trees is pler. This position hs previously een put forwr in stuy of ok woo olor (Klumperset l., 1993). The inonsistent results re likely ue to vritions in silviulturl prtie or site onition ftors, s suggeste y previous reports in tek n other speies (Bht et l., 5; Nelson et l., 1969; Wilkins n Stmp 199). The possile effets of those ftors re not isusse within the sope of this pper ut is worthy of further reserh Reltionship etween termite resistne n extrtive ontents Correltion nlysis (T. II) onfirms moerte negtive orreltion etween the mss loss n NHEC (r =.58) s well s etween the mss loss n TEC (r =.51). This outome is resonle sine tek extrtives re reognize to ply signifint role in termite resistne. The vritions in mss loss with tree ge in the OS n OH region re in generl or with the TEC n NHEC istriution tren. Those results onfirm tht low termite resistne is ssoite with immture woo. For exmple, in the 51-yer-ol group, the trees foun to e the most resistnt to termites h the highest TEC n NHEC, oth in the OS n OH. D Cost et l. (1958) oserve the erese of mss loss with the inrese of TEC level in the OH region. However, the reltionship etween mss loss n TEC or NHEC in the ril position of hertwoo is not ler in this stuy. The IH of 51-yer-ol trees signifintly hs lower TEC n NHEC thn those of the OH, ut without sttistil signifine in the mss loss. This ft my e ue to the ifferenes of the toxi omponent onentrtions whih re inepenent to the pttern of extrtive ontent. In stuies of the ey resistne of tek, Hupt et l. (3), Thulsis n Bht (7) suggest tht the presene of iniviul tive ompouns, even in minor quntities is more signifint thn the mount of totl extrtive ontent. With regr to hemil onsiertion, quinones n their erivtives in tek extrtives, prtiulrly tetoquinone, hve een shown to e toxi to the termites (Rumn n Gy, 1961; Rumn et l., 1958; Snermnn n Simtupng, 1961). This fining supports this ppers preliminry stuy (Lukmnru n Ogiym, 5; 5), whih reporte tht n-hexne n less polr frtions of EtOA solule extrt exhiite ntitermiti properties. Furthermore, tetoquinone ws ientifie s eing primrily responsile for ntitermiti tivity. Wineisen et l. (3) etete tetoquinone n esoxylphol in petroleum ether solule extrts. The vritions of TEC n NHEC in the sme prt n group my prtly explin the onsierle tree-to-tree vrition of termite resistne. Despite the ft tht spwoo is known e esily ttke y termites, exmintion of the termite survivl rtes n mss loss lerly inites tht tek spwoo exhiits ntitermiti tivity leit to lesser egree thn other woo regions. This is more pronoune in the spwoo of 8-yer-ol trees, whih elong to the non-resistnt lss. This inites tht tek spwoo ontins lower levels of ompouns tht re iststeful, repellent, or toxi to termites. A report y Wineisen et l. (3) who etete tetoquinone in the spwoo of tek from Pnm my support tht inition. The high resistne of the spwoo n hertwoo in the 51-yer-ol trees inites tht the ging of toxi onstituents is not evient Reltionship etween termite resistne n olor properties The orreltion etween olor n ey resistne in tek hertwoo hs een investigte. It ws foun tht rightness orreltes negtively with mss loss (Kokutse et l., 6). Bht et l. (5) oserve greter ontent of extrtives, more yellow hertwoo, n higher ey resistne to rownrot fungi in tek grown t ry site home gren n plnttion thn in tek grown in wet site home gren. In this stuy, moerte orreltions re oserve etween mss loss with rightness, s well s etween mss loss with reness of the woo (T. II). Furthermore, orreltion nlysis lso revels moerte orreltion etween the survivl rte in the first week with rightness or reness. This mens the woo 78p7

8 Ann. For. Si. 65 (8) 78 G. Lukmnru n K. Tkhshi is more resistnt when it is rker n reer. The rightness n reness pper to e relte to termite resistne in the spwoo. As expete, the reltively high termite resistne of the IS of 3-yer-ol trees n OS of 51-yer-ol trees orrespon to rker n reer spwoo. There is no signifint ifferene in rightness n reness mong the ril position in the hertwoo of 3-yer-ol trees, whih orrespon well with no signifint ifferenes in mss loss in those regions. However, similr tren is not oserve etween the mss loss n olor prmeters in the OH regions. Those fts suggest tht the reltionship etween the mss loss n olor prmeters is omplex. As it is known tht the olor of woo hs een relte to the quntity n types of woo extrtives, this my inite tht the extrtives ssoite with olor in the OH might e inepenent of those tht use termite resistne. In future stuies, investigtions of more smples n ifferent termite speies will e helpful in etermining the reltionships etween termite resistne n olor properties of the woo. 4. CONCLUSION This stuy emonstrtes tht immture woo exhiits less nturl termite resistne in oth the spwoo n hertwoo. The survivl rte n mss loss level ue to termite exposition is epennt on the intertion of tree ge n ril position. The survivl rte n mss loss levels of spwoo n hertwoo of 8-yer-ol trees re signifintly lower thn those of 3 n 51-yer-ol trees. The survivl rte n mss loss levels in the hertwoo regions of 3 n 51-yer-ol trees re not sttistilly ifferent. The survivl rte in the first week is moertely orrelte to rightness, n reness of the woo. The mss loss is moertely orrelte to NHEC, TEC, rightness, n reness of the woo. Appreile tree to tree vritions re oserve in mss loss even in the sme stn. It shoul e mentione tht ue to the metho of tree smpling, tht the in ition to tree ge other ftors might e involve, inluing geneti origin, growth onition n silviulturl tretment. The omprison of nturl termite resistne prmeters shoul e ielly onfirme with replition of ifferent tree ges within the sme site in orer to minimize huge vritions n inonsistent results. Aknowlegements: We express our grtitue to the Ministry of Eution, Culture, Sports, Siene n Tehnology, Jpn for the finnil support of this investigtion. Thnks re lso irete to Wiynto Nugroho n Tomy Listynto (Fulty of Forestry, Gjh M University) for their ssistne with smple olletion. We lso thnk to Ttsuy Ashitni (Fulty of Agriulture, Ymgt University) n two nonymous reviewers for helpful omments on the mnusript. REFERENCES Beker V.G., On the exmintion n estimtion of the nturl resistne of woo to termites. Holz Roh- Werkst. 19: Bht K.M. n Florene E.J.M., 3. Nturl ey resistne of juvenile tek woo grown in high input plnttions. Holzforshung 57: Bht K.M., Thulsis P.K., Florene E.J.M., n Jyrmn K., 5. Woo urility of home-gren tek ginst rown-rot n whiterot fungi. Trees 19: D Cost E.W.B., Rumn P., n Gy F.J., Investigtions on the urility of Teton grnis, Empire Forestry Review 37: D Cost E.W.B., Rumn P., n Gy F.J., Reltionship of growth rte n relte ftors to urility in Teton grnis. Empire Forestry Review 4: Deprtemen Kehutnn, Hutn Rkyt (Community Forest). Biro Huungn Msyrkt, Deprtemen Kehutnn, Jkrt. Hupt M., Leithoff H., Meier D., Puls J., Rihter H.G., n Fix O., 3. Hertwoo extrtives n nturl urility of plnttion-grown tekwoo (Teton grnis L.) se stuy. Holz Roh- Werkst. 61: Klumpers J., Jnin G., Beker M., n Levy G., The influenes of ge, extrtive ontent n soil wter on woo olor in ok: the possile geneti etermintion of woo olor. Ann. Si. For. 5: KokutseA.D.,Stokes A.,BilleresH., KokouK., n Busse C., 6. Dey resistne of Togolese tek (Teton grnis L.) hertwoo n reltionship with olour. Trees : Lukmnru G. n Ogiym K., 5. Biotive ompouns from ethyl ette extrt of tekwoo (Teton grnis L.f.), Proeeings of the 6th Interntionl Woo Siene Symposium LIPI-JSPS Core, Bli, Inonesi, August 29 31, 5, pp Lukmnru G. n Ogiym K., 5. Biotive extrt from tekwoo (Teton grnis L.f.), Proeeings of Interntionl Symposium on Woo Siene n Tehnology, Volume II: poster presenttions. Yokohm, Jpn, Novemer 27 3, 5, pp Nrynmurti D., George J., Pnt H.C., n Singh J., Extrtives in tek. Sylve Genet 11: Nelson N.D., Meglin R.R., n Whlgren H.E., Reltionship of lk wlnut woo olor to soil properties n site. Woo Fier 1: Ngee P.S., Toshiro A., Yoshimur T., Jl Z., n Lee CY., 4. Woo preferene of selete Mlysin suterrnen termites (Isopter: Rhinotermitie, Termitie). Soioiology 43: Rumn P. n Gy F.J., The uses nturl urility in timer prt VI. Mesurement of nti-termite properties of nthrquinones from Teton grnis L.f. y rpi semi-miro metho. Holzforshung 15: Rumn P., D Cost E.W.B., Gy F.J., n Wetherly A.H., Reltionship of tetoquinone to urility in Teton grnis.nture 181: Rumn P., D Cost E.W.B., n Gy F.J., Woo qulity in plus trees of tek (Teton grnis L.f.): n ssessment of ey n termite resistne. Sylve Genet. 16: Snermnn W. n Simtupng M.H., On the hemistry n iohemistry of tekwoo (Teton grnis L. fil). Holz Roh- Werkst. 24: Suiynto, Pengenln hm inger-inger p jti (The ientifition of tek inger-inger pest). Fkults Kehutnn Universits Gjh M, Yogykrt, Inonesi. Thulsis P.K. n Bht K.M., 7. Chemil extrtive ompouns etermining the rown-rot ey resistne of tek woo. Holz Roh- Werkst. 65: Wilkins A.P. n Stmp C.M., 199. Reltionship etween woo olour, silviulturl tretment n rte of growth in Eulyptus grnis Hill (Mien). Woo Si Tehnol. 24: Wineisen E., Klssen A., n Wegener G., 3. On the hemil hrteriztion of plnttion tekwoo (Teton grnis L.) from Pnm. Holz Roh- Werkst. 61: p8