Escape pattern of the ambrosia beetle Platypus koryoensis (Murayama) based on individual gallery was investigated. The survey was conducted in four oak forests located in Chuncheon, Hanam, Paju and Seongnam, and escape patterns from individual gallery were surveyed using emergence trap attached at the entrances of galleries formed in 2010. The number of adults caught in each trap was periodically counted from May 2011 to September 2012. The adults ambrosia beetle was caught over two years after infestation. The escape patterns in the first and second year after infestation showed different types; in the first year, escape of adults from gallery was observed one or two times whereas escape from gallery was observed two times in the second year with variation in aspect of escape density and timing. Moreover, variations in escape pattern between trees or between galleries in the same tree was observed. Colonization success rate in living tree was higher than that of dead tree, but the number of progeny per gallery in living tree was lower than that of dead tree. Colonization success rate in the galleries of second year was lower than that of first year, but the number of progeny per gallery of second year was higher than that of first year.
The aim of this experiment was to count excreted oocysts and to evaluate gross lesions and histopathological changes in broiler chicks infected with Eimeria; E. acervulina (Ea), E. maxima (Em), and E. tenella (Et). Twelve-day-old broiler chicks without infection with Eimeria spp. were used in this experiment. On day 12, the chicks in group Ea (n=3), Em (n=3), and Et (n=3) received oral inoculation with 5 × 10 sporulated oocysts of Ea, Em, and Et per 1 mL of tap water, while control chicks were injected with tap water of equal amount. The prepatent period (PP) for Ea, Em, and Et was four, five, and six days, respectively. To evaluate the progress of the coccidiosis, post-mortem analysis method and histopathological evaluation were performed two days after PP of Ea and Et, and three days after PP of Em at two-day intervals on one bird from each group. Intestinal segments (Ea, duodenum and upper intestine; Em, mid intestine; and, Et, cecum) of all chicks were obtained from the autopsied birds. Among pathological changes of coccidiosis, target parts of small intestine and caecal pouches showed mucosal petechiation and white plaques streaks in the duodenum. Histopathological evidence showed upper small intestinal villus preserved with different phases of parasite (zygotes, oocysts, macro- and micro-gametocytes) after infection with Ea in broiler chicks. Zygotes in the lamina propria and fusion of middle small intestinal villi in broilers infected with Em and invasion of the caecal crypt of oocysts and granulomatous inflammation of caecal submucosa in broilers infected with Et were found.
Alfalfa (Medicago sativa L.) is one of the most important forage crops in the world and it’s has been known as the best feed materials for dairy cows and other high valued animals. The new uses of alfalfa are being explored as bio-energy, food, medical and biochemical uses. R2R3-type MYB transcription factors play important roles in transcriptional regulation of anthocyanin biosynthesis. The R2R3-type IbMYB1 is known to be a key regulator of anthocyanin biosynthesis in the storage roots of sweetpotato. We previously showed that the expression of IbMYB1a led to anthocyanin pigmentation in tobacco and Arabidopsis. In this study, we generated transgenic alfalfa plants expressing the IbMYB1a gene under the control of CaMV 35S promoter. Overexpression of IbMYBa in transgenic alfalfa produced strong anthocyanin pigmentation in seedlings and generated a deep purple color in leaves, stems, roots, and even in seeds. High performance liquid chromatography (HPLC) analysis revealed that IbMYB1a expression led to the production of cyanidin as a major core molecule of anthocyanidins in alfalfa, as occurs in the purple leaves of sweetpotato (cv.Sinzami). We also examined expression of several structural genes in the anthocyanin biosynthetic pathway in alfalfa by RT-PCR analysis. In this presentation, we will further present molecular and biochemical characterization in IbMYB1a-overexpression lines. This result shows that the IbMYB1a transcription factor is sufficient to induce anthocyanin accumulation in the forage legume alfalfa plants.
Plant peroxidases (PODs) have been shown to reduce hydrogen peroxide (H2O2) in the presence of an electron donor. Extracellular POD also induce H2O2 production, and can perform a significant function in responses to environmental stresses. We previously described the isolation of 10 POD cDNA clones from cell cultures of sweetpotato (Ipomoea batatas). Among them, the expression of the swpa4 gene was profoundly induced by a variety of stresses. In this study, transgenic tobacco (Nicotiana tabacum) plants overexpressing the swpa4 gene under the control of the CaMV 35S promoter were generated in order to assess the function of swpa4. Both transient expression analysis with the swpa4-GFP fusion protein and POD activity assays in the apoplastic washing fluid revealed that the swpa4 protein is secreted into the apoplastic space. The transgenic plants also evidenced a significantly enhanced tolerance to a variety of abiotic and biotic stresses. These plants harbored increased lignin and phenolic content, and H2O2 was also generated under normal conditions. Furthermore, they manifested increased expression levels of a variety of apoplastic acidic pathogenesis-related (PR) genes following enhanced H2O2 production. These results suggest that the expression of swpa4 in the apoplastic space functions as a positive defense signal in the H2O2-regulated stress response signaling pathway.