| Summary: | 碩士 === 國立中興大學 === 昆蟲學系 === 84 === The sliverleaf whitefly, Bemisia argentifolii Bellows &
Perring, is a serious pest of many crops throught the tropics
and subtropics. It can damage plants directly by its feeding and
indirectly by the transmission of several important virus. B.
argentifolii transmitted tomato leaf curl geminivirus (TLCV)
which DNA fragments from an viruliferous female whitefly and
tomato leaves could be amplified by polymerase chain reaction.
Squash-blot hybridization could detect TLCV DNA 5-7 days post-
inoculation by whitefly of 48 h in tomato tissues, such as
leaves, stem, root, flower, and fruits. It also could detect the
presence of TLCV DNA in one female adult of B. argentifolii
after 2 h acquistion-access period and nymphs collecting from
TLCV-infected tomato plants. Transmission of TLCV by female
whiteflies were more efficient than the males. A viruliferous
female whitefly resulted in 29% transmission, while 10
whiteflies/per plant gave 100% transmission. B. argentifolii
transmitted TLCV after a minimum acquistion-access period of 15
min. Transmission rate increased to a maximum after a 24 h
acquisition-access period. B. argentifolii transmitted TLCV
after a minimum inoculation-access period of 15 min.
Transmission rate increased to a maximum after an 48 h
acquisition-access period. After a 24 h acquisition-access
period, B. argentifolii was immediately able to transmit TLCV.
Nucleotide sequencing of TLCV genome reveals that it contains
2739 nucleotides and encodes two open reading frames in the
virus sense strand and four in the complementary sense strand
(V1, nt 291-1061; V2, nt 131-478; C1, nt 2601-1516; C2, nt
1613-1209; C3, nt 1465-1064; C4, nt 2444-2154). TLCV has a
narrow host range confined to members of Solanaceae, such as
Datura stramonium, Lycopersicum esculenyum, Nicotiana
benthamiana, and N. tabacum.
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