Pepper yellow leaf curl disease caused by begomoviruses seriously affects pepper (Capsicum spp.) production in a number of regions around the world. Ty genes of tomato, which confer resistance to the tomato yellow leaf curl virus, are the only begomovirus resistance genes cloned to date. In this study, we focused on the identi cation of begomovirus resistance genes in Capsicum annuum. BaPep-5 was identi ed as a novel source of resistance against pepper yellow leaf curl Indonesia virus (PepYLCIV) and pepper yellow leaf curl Aceh virus (PepYLCAV). A single recessive locus, which we named as pepper yellow leaf curl disease virus resistance 1 (pepy-1), responsible for PepYLCAV resistance in BaPep-5 was identi ed on chromosome 5 in an F 2 population derived from a cross between BaPep-5 and the begomovirus susceptible accession BaPep-4. In the target region spanning 34 kb, a single candidate gene, the messenger RNA surveillance factor Pelota, was identi ed. Whole-genome resequencing of BaPep-4 and BaPep-5 and comparison of their genomic DNA sequences revealed a single nucleotide polymorphism (A to G) located at the splice site of the 9th intron of CaPelota in BaPep-5, which caused the insertion of the 9th intron into the transcript, resulting in the addition of 28 amino acids to CaPelota protein without causing a frameshift. Virus-induced gene silencing of CaPelota in the begomovirus susceptible pepper No.218 resulted in the gain of resistance against PepYLCIV, a phenotype consistent with BaPep-5. The DNA marker developed in this study will greatly facilitate marker-assisted breeding of begomovirus resistance in peppers.

Begomoviruses, transmitted by whiteflies (Bemisia tabaci), have emerged as serious constraints to the cultivation of a wide variety of vegetable crops worldwide. Leaf samples from Solanaceae (tomato, tobacco, and eggplant) and Cucurbitaceae (cucumber and squash) plants exhibiting typical begomoviral yellowing and/or curling symptoms were collected in Northern Sumatra, Aceh province, Indonesia. Rolling circle amplification was conducted using DNA isolated from cucumber, squash, eggplant, and tobacco, and the fulllength sequences of the begomoviruses were evaluated. The following viruses were isolated: bipartite begomoviruses Tomato leaf curl New Delhi virus (ToLCNDV), Squash leaf curl China virus (SLCCNV), Tomato yellow leaf curl Kanchanaburi virus (TYLCKaV), and a monopartite begomovirus Ageratum yellow vein virus (AYVV). Begomovirus diagnosis was conducted by PCR using begomovirus species-specific primers for Pepper yellow leaf curl Indonesia virus (PepYLCIV), Pepper yellow leaf curl Aceh virus (PepYLCAV), ToLCNDV, SLCCNV, TYLCKaV, and AYVV, which are the predominant begomoviruses. The primary begomovirus species for each plant were as follows: PepYLCAV for tomato, AYVV for tobacco, TYLCKaV for eggplant, ToLCNDV for cucumber, and SLCCNV for squash. This study provides valuable information for breeding begomovirus-resistant cultivars as horticultural crops.

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Indonesia is one of the world's largest fresh pepper (Capsicum spp.) fruit-producing countries, and hot peppers are essential spices in Indonesian cuisine. During the last two decades, begomovirus, which is transmitted by the whitefly, Bemisia tabaci (Gennadius), and causes pepper yellow leaf curl disease, began to cause a huge economic loss by damaging pepper plants in Indonesia. In the present study, a highly efficient inoculation method was established for Pepper yellow leaf curl Indonesia virus (

Tomato yellow leaf curl disease caused by begomoviruses is a serious threat to tomato (Solanum lycopersicum L.) production. If begomoviruses, transmitted by whitefly (Bemisia tabaci), infect tomato plants during early growth, production can be almost entirely lost. Tomato yellow leaf curl Kanchanaburi virus (TYLCKaV), a bipartite Begomovirus, is emerging as an important threat to solanaceous crop production in Southeast Asia. The lack of mechanical transmission of some begomoviruses is a major experimental constraint. In this study, an agroinoculation method using TYLCKaV in tomato plants was established. Partial tandem repeats of TYLCKaV DNA A and DNA B were constructed and cloned to a binary pGreenII vector, and their infectivity was tested. Co-inoculation of TYLCKaV DNA A and DNA B to Nicotiana benthamiana L. produced typical begomoviral symptoms, and both of the viral DNA components accumulated in the upper uninoculated leaves, suggesting systemic infection of TYLCKaV. Two agroinoculation methods were conducted on tomatoes. First, excised sections of tomato shoots were agroinoculated with a soaking procedure. Although two Agrobacterium tumefaciens strains were tested, approximately 40% of inoculated plants only showed viral symptoms for EHA105. Second, agrobacterium from a cultured petri dish was directly inoculated with a colony inoculation procedure. When EHA105 was used, approximately 92% of inoculated plants showed viral symptoms. Sequencing the recovered viral DNA from the upper uninoculated leaf clarified that TYLCKaV had successfully infected the tomato plants. The colony inoculation procedure is labor-saving, and viral symptoms develop in susceptible tomato plants within approximately a month from sowing the seeds. This method could contribute to simple and speedy evaluation of TYLCKaV resistance of tomato plants.