Termite Species On Agricultural And Forest Plants In Nanning,and Nesting Characteristics Of Ancistrotermes Dimorphus (Tsai Et Chen)

A survey of termite species on agricultural and forest plants was carried out in Nanning, and the nesting characteristics of the dominant species, Ancistrotermes dimorphus (Tsai et Chen), were investigated. The main feedings of this study are summarized as follows:1. Twenty-two species of termites in10genera under three families were found to be pests in agriculture and forestry in Nanning, among which, A. dimorphus, Odontotermes formosanus (Shiraki), Macrotermes barneyi Light, and M. annandalei (Silvestri) were most damaging. Significant variations in termite demography were detected in different habitats. For example, A. dimorphus and M. barneyi were dominant in Chinese chestnut forests, A. dimorphus and M. annandalei in sugarcane growing areas, and O. formosanus and M. barneyi in eucalypt forests.2. A. dimorphus was a major pest in the Chinese chestnut forests in Longan County, and sugarcane growing areas in Jiangzhou District, Chongzuo City. The infestation rate on chestnut trees was26%-100%(average64.26%), and that on sugarcanes at the harvest was3.67%-79.67%(average30.93%).3. One A. dimorphus nest held average17958±4008头termites (include larvae and eggs), with a maximum of24230individuals. Members in a nest usually included a king (maximum two), a queen (maximum three), and many big dinergates, small dinergates, big ergates, small ergates, nymphs and eggs. The dinergates and ergates constituted0.52%-1.82%and18.45%-69.77%, respectively, of the total population in a nest.4. The nest of A. dimorphus consisted of a palace, and a number of chambers, channels, fungus gardens and swarming holes. The measurements of the palace, chambers and fungus gardens were9.5×8.0×1.6cm,7.5×5.4×2.5cm and5.5×5.4×2.1cm, respectively.5. A. dimorphus made their nests2to65cm below the ground surface, with the palaces mainly distributed between10and45cm below the surface. The A. dimorphus nests were made either independently or inside or around the nests of M. annandalei, M. barneyi and O. formosanus. In the main distribution areas of A. dimorphus in Longan County of Nanning City and Tuolu Town of Chongzuo City,29nests of M. barneyi and87nests of M. annandalei were dissected. Results show that A dimorphus nests were found in82.76%of M. barneyi ones and36.78%of M. annandalei ones.6. In the Chinese chestnut forests the fungus gardens of A. dimorphus usually occurred between2.0cm and52.0cm below the ground surface, with79.66%occurring between2.0and21.9cm below the surface. In the sugarcane field they were generally located between5.0and55.0cm below the surface, with89.62%being between15.0and44.9cm below the surface. In both the Chinese chestnut forests and sugarcane fields the fungus gardens of A. dimorphus were distributed in clusters.7. The ergates and dinergates of A. dimorphus from different nests fought, with the fighting behavior usually occurring≤180s after encounter. Observations on the fighting behavior show that the average activity radius of A. dimorphus was6.23±3.13m, with a maximum of12m.