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The 5'-and 3'-terminal sequences were determined using the 5'/3' RACE Kit 2ndGeneration (Roche). To avoid errors associated with RT-PCR and sequencing, each genomic region was amplified and sequenced at least twice in both directions. Table 2.The complete sequences of isolates LL-N.05, Pujol1TL3 and PVR were aligned and compared with all complete sequences available for TSWV retrieved from GenBank (Table 1) Phylogenetic trees of the nucleotide sequences of the five TSWV ORFs were inferred by the maximum likelihood (ML) method with the nucleotide substitution model best fit for each ORF and 1000 bootstrap replicates to estimate the statistical significance of each node, using the program MEGA V6.0. The phylogenetic relationships of the Spanish TSWV isolates changed for the three genomic segments, but they were very similar for the two ORFs within each segment (Fig. 1) The genetic distances among TSWV isolates were uncorrelated to biotypes (resistancebreakdown ability) or plant hosts (Fig. 1) isolates [16,19,29]. The probable cause is that resistance-breakdown seems to have occurred several times independently and involve a few nucleotide changes as for other plant viruses [4].With respect to plant hosts, some TSWV isolates were more closely related to isolates from other plant species than isolates from the same plant host. E.g isolate TSWV-4 from pepper was closely related to isolate TSWV-10 from Stellaria aquatica, and isolate TSWV-16 from tomato, but distantly related to isolate CY-CN1 from pepper ( Fig. 1). This could be due to that TSWV has similar fitness in different hosts or that only a few nucleotide changes are involved in host adaptation (fitness increase).The complete genome sequences of TSWV isolates with different ability to overcome resistance in tomato and pepper are useful for further studies to understand emergence and evolution of TSWV adaptation to new hosts genotypes which can be applied in breeding programs to develop durable and efficient resistance cultivars against TSWV.

WileySoler Aleixandre, S.; Debreczeni, DE.; Vidal, E.; Aramburu, J.; López Del Rincón, C.; Galipienso Torregrosa, L.; Rubio Miguelez, L. (2015). 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59

Tomato spotted wilt virus (TSWV) causes serious diseases of many economically important crops. Disease control has been achieved by breeding tomato and pepper cultivars with the resistance genes Sw-5 and Tsw, respectively. However, TSWV isolates overcoming these genetic resistances have appeared in several countries. To evaluate the risk of spread of the resistance-breaking isolates, we tested their ability of transmission by the main vector of TSWV, the thrips Frakliniella occidentalis. We compared the transmission rate by thrips of several TSWV isolates with different biotypes, able or unable of overcoming tomato or pepper resistance, and divergent genotypes. Our results indicate that TSWV transmission rate was affected by the viral accumulation in thrips but not by its accumulation in the source plants from which thrips acquired the virus. No correlation was found between transmission efficiency and the ability of overcoming both resistances or between transmission efficiency and the genotype. This suggests that resistance-breaking isolates have the same potential of spread than the isolates unable to infect resistant tomato and pepper cultivars.

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