Doo-Gyung Moon

Effect of Temperature Condition on Nitrogen Mineralization and Soil Microbial Community Shift in Volcanic Ash Soil

This study was carried out to evaluate effect of temperature condition on nitrogen mineralization of organic matter, distribution of microbial group by PLFA profiles, and soil microbial community structure in volcanic ash soil. Dried soil 30 g mixed well each 2 g of pellet (OFPE) organic fertilizers, pig manure compost (PMC), and food waste compost (FWC). And then had incubated at , , and , respectively. Nitrogen mineralization rate increased with increasing temperature and that was in the order of FWC>OFPE>PMC. Distribution ratio of microbial group by PLFA profiles were different significantly caused by incubation temperature and the type of organic matter. As incubating time passed, density of microbial group decreased gradually. The Gram-bacteria PLFA/Gram+ bacteria PLFA, Fungi PLFA/Bacteria PLFA, and Unsaturated PLFA/saturated PLFA ratios were decreased according to the increasing temperature gradually. But cy19:0/ ratio increased both FWC and PMC treatment. Principal component analysis using PLFA profiles showed that microbial community structure made up clearly at both 75 days () and 270 days () by temperature factor. As incubating time passed, microbial community structure shifted gradually.

Plant growth and fruit quality as affected by canopy locations in ‘Shiranuhi’ mandarin

Fruit quality (soluble solids and acidity) and growth properties of fruiting branches in different canopy positions (upper, middle, and lower) of ‘Shiranuhi’ mandarin [(C. unshiu × C. sinensis) × C. reticulate] trees were determined during fruit maturation. Length, diameter, and number of leaves per fruiting branch increased in order from the upper, through the middle, to the lower parts of the canopy. Fruit diameter, fruit weight, pulp weight and pulp thickness were also highest in the upper part. Transverse sections of stem end protrusions in fruit from the upper, middle, and lower parts of the tree canopy were 37.3 ± 2.3 mm, 33.2 ± 0.2 mm and 32.1 ± 0.4 mm, respectively. Soluble solid content increased during fruit maturation at all locations within the canopy and was highest in the upper part. Likewise, acid content decreased with fruit maturity and was lowest in the lower part. These results suggested that harvesting be staggered starting with fruit from the upper part of the canopy as part of crop management in ‘Shiranuhi’ mandarin for direct effect on fruit quality.

Effect of Temperature Condition on Nitrogen Mineralization of Organic Matter and Soil Microbial Community Structure in non-Volcanic Ash Soil

This study was carried out to evaluate effect of temperature condition on nitrogen mineralization of organic matter, distribution of microbial group by PLFA profiles, and soil microbial community in non-volcanic ash soil. Dried soil 30 g mixed well each 2 g of pellet (OFPE) organic fertilizers, pig manure compost (PMC), and food waste compost (FWC). And then had incubated at , , and , respectively. Nitrogen mineralization rate increased with increasing temperature and that was in the order of FWC>OFPE>PMC. Distribution ratio of microbial group by PLFA profiles showed that was different significantly according to incubation temperature and the type of organic matter. As incubating time passed, density of microbial group decreased gradually. The Gram-bacteria PLFA/Gram+ bacteria PLFA, Fungi PLFA/Bacteria PLFA, and Unsaturated PLFA/saturated PLFA ratios were decreased according to the increasing temperature gradually. Principal component analysis using PLFA profiles showed that microbial community structures were composed differently by temperature factor at both 75 days () and 270 days (). In conclusion, Soil microbial community structure showed relative sensitivity and seasonal changes as affected by temperature and organic matter type.

Changes of Fruit Cracking Percentage and Fruit Shape of `Hei` Black Tomato with Increased Temperature

`Hei` (Lycopersicon Esculentum Mill.) Black Tomato examined changes in fruit shape, fruit weight and cracking percentage with increasing temperature in high-rise tomato greenhouse during long-term cultivation in summer season. Fruit diameter is greater than fruit length from the first cluster to the ninth cluster. However, fruit length is longer than fruit diameter from the tenth cluster to the fifteenth cluster. Fruit shape index (L/D) is below 100% from the first cluster to the ninth cluster and above 100% from the tenth cluster to the fifteenth cluster. Fruit weight was decreased during temperature increasing in greenhouse. However, fruit cracking percentage was increased to temperature increasing during cultivation period. Thus, fruit shape, fruit weight and fruit cracking of `Hei` black tomato were influenced by increasing of temperature in greenhouse during long-term cultivation.