4Klein A M, Vaissiere B E, Cane J H, et aL. Importance of pollinators in changing landscapes for world crops [ J ]. Proc. Biol. Sci. , 2007,274(1608) :303 - 313.
5Shen M, Cui L, Ostiguy N, et al.. Intricate transmission routes and interactions between picoma-like viruses ( Kashmir bee virus and sacbrood virus) with the honeybee host and the Parasitic varroa mite[J]. J. Gen. Virol. , 2005,86(8) :2281 - 2289.