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Since 2006, we have worked on the establishment and dissemination of an Integrated Pest Management（IPM）program in cooperation with agricultural extension officers, related research organizations, and IPM product companies in Japan. Today, 12 years have passed, and the use of IPM with biological control agents（BCA）has spread to many agricultural production sites. Dissemination and extension activities of IPM were promoted not only in the greenhouse cultivation of tomatoes, strawberries, sweet peppers, cucumbers, eggplants, melons, watermelons, or-namentals, and citruses, but also spreading to eggplants in the open field from 2015. As a result, in strawberries, sweet peppers, eggplants, cucumbers, and citruses grown in greenhouse, IPMs, which are mainly used by natural enemies as the main BCA, are considered to have increased dramatically due to the following three major contributions. 1）For a stable and successful IPM program, it was important to let the natural enemy density grow before increasing pest in-sects by using generalist predatory mites, such as Neoseiulus californicus and Amblyseius swirskii. 2）Demonstration tests were conducted in which extension officers planned, verified, and evaluated with the growers, which led to an improvement in their knowledge and skills. 3）As we conducted multifaceted demonstration tests in Japan, the sharing of information on the techniques of using IPM programs has progressed in a short period of time. However, for tomatoes, ornamentals, melons, and watermelons, a lack of solution tools against disease control and the cost performance of control programs have been issues, and the use of IPM programs is becoming less popular. In order to establish IPM techniques, we think it is important to conduct dissemination activities for showing the benefits of IPM leading to problem-solving for each region and grower, and for growers to recognize the merit of selecting IPM. [ABSTRACT FROM AUTHOR]

In June 2017, sweet pepper plants showing chlorosis in leaves and fruits were observed in Susaki City, Kochi Prefecture, Japan. We had named the disease pepper chlorosis (Tairyoku-byo). A phytoplasma was observed by electron microscopy and identified as 'Candidatus Phytoplasma solani', based on homology searches and molecular phylogeny using nucleotide sequences of 16S rDNA. To our knowledge, this is the first report showing the occurrence of 'Ca. P. solani' in Japan. [ABSTRACT FROM AUTHOR]

Pungency is a characteristic trait of pepper (Capsicum spp.). Two genes, Punl and pAMT, are known as determinative factors of pepper pungency. To date, it has been considered that most bell-type sweet peppers (called piman and paprika, in Japan) possess the identical mutated Punl allele, punl, whereas pAMT mutated non-pungent pepper has been found only in non-bell-type pepper. In this study, to reconsider the uniformity of the source of non-pungency in sweet bell pepper and explore new genetic resources, the presence of punl was investigated in 26 sweet bell pepper varieties. Among them, a seemingly common sweet bell pepper 'Color Piman Yellow' had the intact Punl, in spite of its non-pungency. Sequencing and linkage analyses revealed that 'Color Piman Yellow' possessed a novel mutated pAMT allele, pamt10, that has a nonsense substitution at the 11th exon responsible for non-pungency. This is the first pAMT mutant to be found in sweet bell pepper. The finding that there was a pAMT mutant in sweet bell pepper suggests the possibility that more pAMT mutants exist unconsciously in other sweet bell peppers. The discovery of a new factor of non-pungency contributes to expanding the genetic diversity of sweet pepper varieties. [ABSTRACT FROM AUTHOR]

Severe fruit rot of sweet pepper was found in Shimane, Hyogo, Chiba, Toyama, and Nagano prefectures, Japan from 2005 to 2011. Dark, sunken spots with concentric rings of orange conidial masses appeared on fruits. Pathogenic isolates from diseased fruits in the prefectures were identified as Colletotrichum scovillei. This species was added to the pathogens of sweet pepper anthracnose in Japan. The representative isolate was pathogenic to sweet pepper, tomato and chili pepper fruits, kidney bean pod, azuki bean, pea and strawberry leaves, but a caused no symptoms on cucumber or carrot in inoculation tests. [ABSTRACT FROM AUTHOR]

Sweet peppers (cv. Tosajishi beauty) with leaf blight symptoms were observed in Kochi Prefecture, 2003. Initially, small spots formed on leaves, and later enlarged to brown to dark brown spots, and eventually blighted leaves fell. Several bacteria that caused the same symptoms were isolated and subsequently reisolated. These bacteria were identified as Pseudomonas cichorii on the basis of bacterial characteristics and the 16S rRNA gene sequence. This is the first report of bacterial leaf blight in the sweet pepper in the world. [ABSTRACT FROM AUTHOR]

In order to develop a method for discrimination of Corynespora cassiicola isolates pathogenic to sweet pepper among Japanese isolates, this study analysed pathogenic variations of 64 Japanese isolates of C. cassiicola on perilla, cucumber, tomato, aubergine and sweet pepper, and their multigene phylogeny. Japanese isolates were divided into seven pathogenicity groups (PG1-PG7). The virulence of isolates in PG1-PG5 was restricted to perilla, cucumber, tomato, aubergine and sweet pepper, respectively. Isolates in PG6 were virulent to sweet pepper, tomato and aubergine. Isolates in PG7 were avirulent to all tested plants. Multigene phylogenetic analysis of the isolates based on β-tubulin, translation elongation factor 1-α, calmodulin and actin genes showed three divergent clusters, MP-A, MP-B and MP-C. These clusters included all isolates in PG1, PG2, PG8 and PG9 (MP-A), PG3 and PG5 (MP-B) and PG4 and PG6 (MP-C). Isolates in PG7 were distributed amongst all clusters. Furthermore, random amplified polymorphic DNA (RAPD) analysis using universal primers, Q17 (5′-GAAGCCCTTG-3′) and Q13 (5′-GGAGTGGACA-3′), facilitated discrimination of isolates virulent on sweet pepper amongst isolates in MP-B and MP-C, respectively. Together, a combination of the multigene analysis and the RAPD technique allowed the discrimination of the isolates virulent to sweet pepper. [ABSTRACT FROM AUTHOR]

A tobamovirus, belonging to the P1 pathotype, was isolated from sweet pepper (Capsicum annuum) in Kochi Prefecture, Japan and was identified as the Paprika mild mottle virus Japanese strain (PaMMV-J). Unlike a reported PaMMV strain incapable of infecting tomato plants, PaMMV-J occasionally infected tomato plants, although the infectivity was lower than that of Tomato mosaic virus. Analysis of the distribution and replication of PaMMV-J in tomato using in vitro RNA transcripts from the cDNA clone of PaMMV-J suggest that the low infectivity of PaMMV-J to tomato plants is due to low levels of both replication and cell-to-cell movement. [ABSTRACT FROM AUTHOR]