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A representative isolate KU53 of the predominant Penicillium species was obtained from rice samples from rice processing complexes of National Agricultural Cooperative Federation in Korea. In this study, isolate KU53 was identified by its morphological and molecular characteristics. The macro- and microscopic characteristics of isolate KU53 were compared with the P. fellutanum reference isolate KCTC16913 on different media; isolate KU53 was generally identical to those of the reference isolate KCTC16913. In a molecular-based identification, the β-tubulin and translation elongation factor 1-alpha sequences of isolate KU53 was most closely related to those of P. fellutanum. Thus, isolate KU53 from stored rice could be identified as P. fellutanum, some isolates of which are known to produce mycotoxin-related metabolites. To our knowledge, this is the first detection of P. fellutanum from stored rice in Korea.

Occurrence of plant diseases is dependent on various factors in the agricultural system. Due to recent extensive environmental climate changes, i.e. global warming, agricultural systems such as planting dates and cultivars are being affected. Gradual transition in disease occurrence and incidence in the agricultural fields can also be affected by direct and/or indirect environmental changes. In this study, we evaluated disease occurrence and incidence in soybean plants to investigate whether it could be related with cultivars, planting dates and geographical differences in Korea in 2008. Soybean cultivars including `Taekwang`, `Pungsan`, `Cheongja 3`, `Saeol`, and `Dawon` were planted in four different dates, May 15, June 1, June 15, and June 30, in two locations, Suwon, and Naju. Soybean diseases such as wild fire and bacterial pustule were mainly found depending on cultivars, planting dates, and areas. Wild fire occurred severely on cv. `Taekwang` while bacterial blight did on cv. `Dawon` among tested cultivars. Disease developments of wild fire and bacterial blight generally decreased in delayed planting regardless of cultivars.

We evaluated microbial populations and aflatoxin production in unhulled and white rice from rice processing complexes of the National Agricultural Cooperative Federation in five regions in Korea and identified three predominant Aspergillus species. Fungal and bacterial populations in rice samples were significantly different between regions in 2007. Aflatoxins were also detected and varied at the levels of 2.45 - 3.43 ng per g unhulled rice grain and 1.29 - 2.09 ng per g white rice grain. Unhulled rice generally detected higher level of aflatoxins than white rice regardless of sampling regions; however, no significant differences were found in Anseong and Cheonan in 2005 and Cheonan and Gimpo in 2007. Aflatoxin production between sampling regions was not different regardless of rice type and sampling year. Although the fungal diversity was highly distinct from region to region, three Aspergillus isolates were predominant in the rice samples; thus, representative isolates AC317, AF57, and AF8 were selected and identified based on their morphological and molecular characteristics. Consequently, isolates AC317, AF57, and AF8 were identified as A. candidus, A. flavus, and A. fumigatus, respectively. These fungi can produce mycotoxins that are harmful for consumers and thus it is important to detect and reduce the population of storage fungi in rice.

We have previously obtained a representative isolate KU101 of the predominant Penicillium species from rice under indoor storage conditions. In this study we attempted to characterize isolate KU101 using its morphological and molecular characteristics. When the micro- and macroscopic characteristics of isolate KU101 were compared with the P. islandicum reference isolate KCCM 34763, isolate KU101 was generally identical to those of isolate KCCM 34763, however, isolate KU101 grew faster and produced more orange to red pigments than isolate KCCM 34763. In a molecular-based identification, the nuclear sequence of the ITS1-5.8S-ITS2 region of isolate KU101 was most closely related to that of P. islandicum. Therefore, these results indicated that isolate KU101 from stored rice could be identified as P. islandicum, some isolates of which are known to produce mycotoxins.

This research was conducted to evaluate fungal and bacterial populations in unhulled and brown rice under indoor storage conditions, and to examine the relationship between microbial populations and environmental conditions such as temperature and relative humidity. The temperature and relative humidity of the storage room ranged from and 23.3% to 44.2%, respectively. Total fungal and bacterial populations remained relatively stable over the storage period. Predominant fungi included Aspergillus candidus, A. flavus, A. fumigatus, and Penicillium spp.; the predominant bacteria were Bacillus, Microbacterium, Sphingomonas, and Methylobacterium spp. Total fungi and bacteria were not significantly correlated with either unhulled (r

This study was to examine the efficacy of a root-dipping application of antagonistic bacterial strains for the control of Phytophthora blight of pepper caused by P. capcisi, and to evaluate their plant growth-promoting effects in the field in 2005 and 2006. The candidate antagonistic rhizobacterial strains CCR04, CCR80, GSE09, ISE13, and ISE14 were treated by dipping plant roots with bacterial suspensions prior to transplanting. The candidate rhizobacterial strains CCR04, CCR80, GSE09, and ISE14 significantly (P