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松材线虫病与松墨天牛研究概况 总被引:14,自引:0,他引:14
松材线虫病Bursasphelenchusxylophilus是松树的毁灭性病害。最早由美国的Steiner ,Q等在路易斯安那州的沼泽松Pinuspalustris的木材中发现 ,后由Nickle,W .R定名。但美国的研究工作开展较晚 ,是从 1979年在密苏里州发现由松材线虫造成松树萎焉后才开始研究的 (彭趋贤 1990 )。现在已有 33个州发生。世界上研究最早的是日本。矢野 190 5年首先在长崎市周围的松林中发现松树萎焉 ,之后进行了调查研究 ,1913年作了报道 ,虽然当时未能明确是松材线虫病 ,但所记述的症状实际上就是现在… 相似文献
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重庆松墨天牛发生规律研究 总被引:2,自引:0,他引:2
松墨天牛Monochamus alternatus Hope在重庆1 a发生1代,主要以3~4龄幼虫在受害马尾松木质部的蛀道内越冬。4月下旬成虫开始羽化。11月初幼虫开始越冬。各地区因海拔和特殊地理环境的不同,成虫羽化时间稍有差异。松脂掩埋和寄生是导致卵不孵化的主要原因。幼虫蛀入前是死亡率最高的阶段(达到48.6%)。种群趋势指数I=18 239.13/1214=15.02。通过对重庆地区松墨天牛发生规律的研究,以期对有效控制松墨天牛的发生危害和松材线虫病在西南地区的传播蔓延提供一定的理论指导。 相似文献
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以松墨天牛幼虫为实验材料,研究了其肠道内纤维素酶的组成和酶解动力学特征等。结果表明,松墨天牛幼虫肠道内有完整的纤维素酶系,其中以C1酶活性最强,Cx酶次之,β-1,4-葡萄糖苷酶活性最弱;C1酶、Cx酶和β-葡萄糖苷酶3者的最适作用温区分别为35~55、45~55、40~50℃,最适pH值分别为5.0、5.6、5.0;Cx酶具有最强的热稳定性(65℃,2h),C1酶次之(55℃,2h),β-1,4-葡萄糖苷酶最低(50℃,1h)。此外动力学参数比较揭示,C1酶具有最大的Vmax和km,分别为1.0838和0.7632,β-1,4-葡萄糖苷酶和Cx酶分别具有最小的Km(0.1832)和Vmax(0.4339),但β-萄糖苷酶具有最大的酶解初速度(0.5938)。 相似文献
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Kazumasa Ohta Kazuhiko Hoshizaki Katsunori Nakamura Akihiko Nagaki Yoichi Ozawa Aoi Nikkeshi Akifumi Makita Kazumi Kobayashi Osamu Nakakita 《Journal of Forest Research》2012,17(4):360-368
During the last few decades, pine wilt disease has spread to cool-climate regions in Japan and, more recently, the potential risk of it spreading into the European midwest has also become a concern. In a coastal pine stand (84.7?ha) in Akita, near the northern limit of pine wilt disease in Japan, we investigated seasonal variations in the incidence of damage caused by the disease to trees and oviposition by the disease’s insect vector, Monochamus alternatus, during a two-year period. Foliage discoloration occurred throughout each year, and its seasonal variation showed a bimodal pattern in Pinus thunbergii (a higher peak in May–June and a smaller peak in October) and a clear peak in June in P. densiflora, which differed from the patterns in seasonal variation seen for warm-climate regions. Oviposition scars by M. alternatus were found in 40–45% of the trees damaged each year. The percentage of trees that had oviposition scars was higher in P. thunbergii than in P. densiflora. This appeared to reflect the difference in seasonal discoloration pattern between the two species. Analysis of the oviposition risk showed that trees that exhibited discoloration starting between July and October had a significantly higher risk or significantly higher oviposition scar densities, particularly for those that became discolored between August and September (2.5–14.6-fold higher risk than during other months). Oviposition scar densities per damaged tree were similar within the period of higher oviposition risk. Considering both oviposition risks and scar densities, we concluded that trees with discoloration that become apparent between July and October are important targets for preventing the spread of pine wilt disease in Akita. 相似文献
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采取挂设诱捕器的方法,于2015—2016年调查了南安罗山国有林场松墨天牛成虫种群活动情况。结果表明:松墨天牛成虫一年有2个较集中的高峰,以5—7月数量居多,10—11月次之。5—7月每月的虫口数量占全年总数量的比例均达20%以上,3个月累计可达80%。10—12月也有少量虫口,3个月累计占全年总数量约10%。根据松墨天牛成虫活动情况,对生产上松墨天牛和松材线虫病防治提出了具体对策。 相似文献
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Pine wilt disease is caused by the pine wood nematode [Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle]. In East Asia, an important vector of the nematode is Monochamus alternatus Hope. We determined the tolerance and reproductive ability of sawyer beetles and the nematode to altitude and temperature at elevations between 850 and 1,450 m on Mt. Fuji in Japan. The number of emergent adults decreased markedly along the altitudinal gradient, but the beetle could still reproduce at 1,050 m (8.2 °C annual mean temperature). Beetles with a 2-year life cycle increased rapidly in number with increasing altitude. The pine wood nematode survived through winter at all altitudes tested (850–1,450 m). The beetle population decreased between 950 (9.1 °C) and 1,150 m (8.3 °C). Therefore, the beetle population seems to be stable at 850 m (10.2 °C) and lower altitudes (higher temperatures) but cannot be maintained from 950 (9.1 °C) to 1,150 m (8.3 °C) without constant immigration of beetles from lower altitudes. The beetles could not reproduce at altitudes above 1,150 m (lower than 8.2 °C). From the mean and effective cumulative temperatures, we concluded that the beetle (and its population) can endure temperatures lower than those previously reported. Pine wilt disease also occurred at lower temperatures and higher altitudes than expected. We have summarized the principal strategies for controlling the disease at high altitudes based on these results. 相似文献