Incidence, Distribution and Characteristics of Major Tomato Leaf ...

Isolate IG1
Incidence, distribution and characteristics of major tomato leaf curl and mosaic virus diseases
Isolate IG1 tested positive in PCR with primers PAL1v1978 and PAR1c715 (Figure 3.12
C). It was also positive when primers PARAv 494 and PARAc 1048 were used. Purified
sample IG1 DNA was cloned with a TOPO vector, and when sequenced gave a forward
viral sense sequence of 482 nt in size, and a reverse coat protein sequence of 521 nt. The
coat protein was part of the upper part of the circular DNA presented in Figure 3.13.
From these partial sequences, primers PTLCV-UGrep2r, PTLCV-UGcp1f and PTLCV-
UGcp1r were synthesized (Table 3.12).
Isolate RL5 (DNA Intergenic Region)
In PCR, isolate RL5 reacted positively to TYLCV-Is specific primers (PTYCRv 21 and
PTYCRc 287) as indicated in Figure 3.12E, and was also positive to TYLCV-Is in an
experiment with primers PTYC2v 1499 and PTYAL1c 2196 (Figure 3.13F and Table
3.13). Purified DNA (fluorimeter reading of 268 ng/µl) of type isolate RL5 amplified
with primers PTYCRv 21 and PTYIRc 287 for the TYLCV-Is common region auto
produced a 277 nt TYLCV sequence (excludes vector and primers segments as well as
overlapping) (Figure 3.14). From these results, isolate RL5 was positive to TYLCV-Is,
and was therefore tentatively named TYLCV-Ugandan isolate (TYLCV-UG).
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