| The veins of the typical of the tumor galls were formed on shoots, petiole of Eucalyptus, which were caused by Leptocybe invasa Fisher & LaSalle. Eucalyptus plantation which was greatly damaged stopped growth or death. It had become a critical hindrance to the healthy development of Eucalyptus plantation. In order to find new comprehensive control method for Leptocybe invasa Fisher & LaSalle, this paper divided insect resistance grade of the Eucalyptus clones, on this basis, from the chemical ecological angle, analysed on chemical compositon from injured leaves and its taxis behavior of Leptocybe invasa Fisher & LaSalle. Studed on the influence of turpentine on Leptocybe invasa Fisher & LaSalle and Aprostocetus sp.. The main results were as follows:1. Through the field investigation and artifical inoculation eight Eucalyptus clones, and according to the adults lay eggs, larval development and gall formation damage symptoms, found that 1-2-year-old Young Eucalyptus plantation were easy to be infected by Leptocybe invasa Fisher & LaSalle. Insect resistance of eight Eucalyptus clones had obvious difference and was divided into high sensitive and low resistant. DH201-2 clone was high sensitive. GL-UG9, GL-U4, DH32-26, DH33-27, DH32-28, DH184-1 and GL-WC3 clones were low resistant.2. The volatile of injured fresh leaves from 1-2-year-old eight Eucalyptus clones by Leptocybe invasa Fisher & LaSalle was extracted by the method of water vapor distillation. The extraction rate of volatile of injured leaves from 1-year-old eight Eucalyptus clones was from 0.09% to 0.28%. The extraction rate of volatile of injured leaves from 2-year-old eight Eucalyptus clones was from 0.07% to 0.25%.Among which the extraction rate of volatile oil of injured leaves from DH201-2 clones was the highest and reached 0.28%.3. The volatile of injured fresh leaves from 1-2-year-old eight Eucalyptus clones by Leptocybe invasa Fisher & LaSalle mainly included eight material categories by GC-MS. Relative percentage content of epoxy compounds and hydrocarbon was the highest, especially in 1,8-cineol(34.58%). In addition, relative percentage content of a-terpineol, terpinyl acetate and α-Pinene was higher. Terpenoid compounds were major components of the volatile oil of injured fresh leaves from 1-2-year-old eight Eucalyptus clones by Leptocybe invasa Fisher & LaSalle.4. Relative percentage content of epoxy compounds of volatile of injured fresh leaves from 1-year-old DH201-2 clone was respectively 13.86%,13.42%, 15.80%,6.83%,0.80%,13.72%,11.30% higher than GL-U4, GL-UG9, DH32-26, GL-WC3, DH184-1, DH32-28, DH32-27 clones. In the same clone, along with the increase of tree age, relative percentage content of epoxy compounds of volatile of injured fresh leaves from 1-year-old DH201-2 clone was 3.87% higher than 2-year-old DH201-2 clone, but hydrocarbon were lower 11.56%.5. Taxis test indicated:in the final selection regions of four-arm olfactometer, DH201-2, GL-UG9, GL-U4, GL-WC3, DH32-28, DH184-1, DH32-27, DH32-26 clones, the inducing rate to Leptocybe invasa Fisher & LaSalle adult caused by clone leaf volatiles were 7.07,3.05,1.65,2.06,2.57, 3.22,2.43,2.29 times higher than control group (air), of which the difference between DH201-2, DH184-1, DH33-27 and control group were obvious (p<0.05). The inducing rate to Leptocybe invasa Fisher & LaSalle adult caused by DH201-2 clonal leaf volatiles was 1.67-2.73 times to other seven clones, of which the difference between DH201-2 and GL-U4, DH32-28, DH33-27, DH32-26 were obvious (p<0.05). Eight Eucalyptus clones leaf volatiles was borne two years after Leptocybe invasa Fisher & LaSalle damage, producing inducing effort for choice behavior of Leptocybe invasa Fisher & LaSalle adult’s host.6. After spraying turpentine of concentration of 0.75%,3.75%,7.5% indoor, the eclosion peak time of Leptocybe invasa Fisher & LaSalle and Aprostocetus sp. were 5 days prior to the control group. The eclosion number of Leptocybe invasa Fisher & LaSalle was more than that of Aprostocetus sp., and no hole appeared in both eclosions after 21 days. During the 4th to 5th day, both eclosions came to the peak time, female and male eclosion number of Aprostocetus sp. were 39 and 35 less than that of Leptocybe invasa Fisher & LaSalle respective. In the very day of eclosion peak time, after spraying 3.75% turpentine, eclosion number of Leptocybe invasa Fisher & LaSalle was 28 more than that of the control group. After spraying turpentine with concentration of 15%,37.5%, the lasting days of Leptocybe invasa Fisher & LaSalle eclosion was 12 days (15%) less than control group, even no hole be seen in both eclosion (37.5%).7. After spraying turpentine of concentration of 0.75%,1.5%,7.5% in forest, the eclosion number of Leptocybe invasa Fisher& LaSalle appeared 3 peaks, which were the 6th day (control group), the 11th day (7.5%) and the 12th day (0.75%) day after spraying turpentine respective. During the first 6 days, the most eclosion number of Leptocybe invasa Fisher & LaSalle were those treated with CK, about 640. For the 11 to 12 day, eclosion number of Leptocybe invasa Fisher & LaSalle treated by 0.75% and 7.5% concentration were 560 and 160 more than the control group respective. However, the eclosion total number for 0.75%,7.5% concentration and CK were almost the same, which was close to 2600. Therefore, spraying turpentine in woodland could delay the eclosion speed of Leptocybe invasa Fisher & LaSalle. |
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