The Symbiotic Relationship Between And Its Carrying Bacteria

The study adopted 48 bacterial strains which are isolated directly from the disease wood and already be identified. These disease wood are picked from different epidemic areas, disease stages, and pine species. The main results are as follows:1. Eggs of axenic Bursaphelenchus xylophilus(ABX) were kept on the colonies of various strains, and the results showed that on slanting cultures of certain strains, the eggs hatched, developed and reproduced well, i.e. ABX completed a life cycle merely on the bacteria themselves and/or the nutrition provided by the strains mainly belonging to the genus, Pseudomonas.2. When ABX eggs were cultured with the calluses of Pinus thunbergii and bacterial strains, axenic eggs also hatched , developed and reproduced in the calluses and dilutions of some strains which are all belong to Pseudomonas, the wilting-causing bacteria.3. Studies of influences of ABX-carried bacterial strains on the ABX reproduction indicated that 10 Pseudomonas strains promoted the propagation of ABX. Those strains include: GcM5-1 A Pseudomonas fluroescens, ZpB2-1A P.fluroescens, GcM6-2AP. putida, GcM6-1A P. putida, ZpBl-2A P. putida, GcM2-3A P. putida, EeM-139A Pseudomonas sp. , HeM2A Pseudomonas sp. , HeM1A Pseudomonas sp. , GcM 1-3 A P. cepacia.4. Studies of influences of ABX on the reproduction of ABX-carried bacterial strains showed ABX played a positive or negative role in the propagation of different strains and promoting effects were observed among the tested 12 out 14 strains from the Genus, Pseudomonas.5. Results indicated that 10 Pseudomonas strains promoted the propagation of ABX and vice versa, revealing a mutualistic symbiotic relationship between the two organisms.Results above showed that there is mutualistic symbiotic relationship between Bursaphelenchus xylophilus and majority of the ABX-carrying bacterial strains from the genus, Pseudomonas, Obviously, those pathogenic bacteria were not contaminated the nematode by chance. The study first reported that mutualistic symbiotic relationship existed between pine wood nematode and its carrying bacteria which belonged to genus, Pseudomonas.