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.

The tomato leaf curl New Delhi virus (ToLCNDV) is a bipartite begomovirus (genus Begomovirus, family Geminiviridae) that was originally isolated in India, but has become a serious threat to various horticultural crops in the Indian subcontinent, Southeast Asia, East Asia, Middle East, and western Mediterranean Basin. In Southeast Asia, East Asia, and the western Mediterranean Basin, ToLCNDV has caused huge economic damage to cucurbit crops (cucumber, melon, squash, and zucchini) for which commercial ToLCNDV-resistant cultivars are currently unavailable. In this study, full-length ToLCNDV viral sequences were isolated from cucumber, melon, and zucchini plants exhibiting yellow leaf curl disease in Almeria, Spain. Phylogenetic analysis showed that the isolated viruses consisted of the ToLCNDV-ES strain and strains that were genetically distant from ToLCNDV- in Southeast Asia, which were previously isolated in the Aceh province of Indonesia. Infectious clones of ToLCNDV-[ES-Alm-Cuc-16] from Spain and of ToLCNDV-[BACu-20] from Indonesia were prepared, and ToLCNDV isolates were agroinoculated to Nicotiana benthamiana, tomato, and cucurbit crops (cucumber, melon, and zucchini). Infection rates were nearly 100% for all inoculated plant species, and disease symptoms were consistently more severe in plants inoculated with ToLCNDV-[BACu-20] compared to plants inoculated with ToLCNDV-[ES-Alm-Cuc-16]. For tomatoes inoculated with ToLCNDV-[ES-Alm-Cuc-16], infection occurred without symptoms in most plants, and only a few plants showed slight vein-yellowing symptoms. In contrast, ToLCNDV-[BACu-20] infection induced typical begomoviral disease symptoms of yellowing and curling of leaves in the same tomato cultivar.The present study highlights the importance of screening genetic resources for ToLCNDV resistance by using ToLCNDV isolates from the intended production area; furthermore, the agroinoculation method used in this study will facilitate breeding resistance against both the Southeast Asian and Mediterranean ToLCNDV isolates.

Tomato yellow leaf curl virus (TYLCV), a monopartite begomovirus that originated in the Eastern Mediterranean, has spread worldwide, becoming a serious threat to tomato (Solanum lycopersicum L.) production. Southeast Asia is considered one of the hotspots for begomovirus diversity, and a wide variety of local begomovirus species distinct from TYLCV have been identified. In this study, the protection effect of introgressions of single TYLCV Ty resistance genes, Ty-2 and Ty-3a, in tomato was examined against inoculations of the bipartite begomoviruses Tomato yellow leaf curl Kanchanaburi virus (TYLCKaV) and Pepper yellow leaf curl Indonesia virus (PepYLCIV) isolated from Indonesia. Our findings suggest that Ty-2 in the heterozygous state was found to be ineffective against PepYLCIV and TYLCKaV, whereas Ty-3a in the heterozygous state was effective against PepYLCIV and partially effective against TYLCKaV. Quantification of viral DNAs showed correlation between symptom expression and viral DNA accumulation. Moreover, mixed infections of TYLCKaV and PepYLCIV caused notably severe symptoms in tomato plants harboring Ty-3a. In cases of mixed infection, quantifying viral DNAs showed a relatively high accumulation of PepYLCIV, indicating that Ty-3a loses its effectiveness against PepYLCIV when TYLCKaV is also present. This study demonstrates the lack of effectiveness of Ty resistance genes against single and mixed infections of distinct local begomoviruses from Southeast Asia.

Pertumbuhan Tunas Pisang Barangan Akibat Pemberian Benzyl AminoPurin dan Arang Aktif secara In Vitro Accretion of Barangan Banana Shoot Effect of  (BAP)  and Activated Charcoal Explant by In VitroAbstrak. Banana as a superior product of horticultural crops, has not achieved high productivity and has several obstacles in its multiplication. Tissue culture is one solution to overcome this problem. This study aims to determine the composition of PGRBenzil Amino Purine (BAP) and activated charcoal that are appropriate in the multiplication of barangan banana shoots. This research was conducted at the Tissue Culture Laboratory Faculty of Agriculture Syiah Kuala University, Darussalam Banda Aceh. The design used was a Completely Randomized Design (CRD) with two treatment factors. The first factor is BAP concentration consisting of 3 levels, namely 4 mg/L, 6 mg /L, and 8 mg/L. The second factor is activated charcoal concentration consisting of 3 levels, namely control, 1 g/L and 2 g/L. In this study, from 9 treatment combinations, only 4 treatment combinations were not contaminated. Of the 4 treatment combinations the combination of BAP concentration of 6 mg/L and control (without activated charcoal) showed the fastest shoot growth time of 29 days after multiplication, the most shoot growth was 6 shoots and the average shoot height was 15.9 mm