Tulsi (Ocimum sanctum), commonly known as Holy Basil is a revered herb with a rich history in traditional medicine systems, particularly in Southeast Asia. For its medicinal properties, Tulsi has been regarded as an “Elixir of Life” and has been used to treat various ailments. However, the comprehensive investigation of Tulsi extracts and their potential pharmacological benefits, specifically in relation to antioxidant activity remains limited. Hence, the objective of this study was to evaluate the antioxidant activity of Tulsi leaf and stem extract using various screening methods. We investigate the antioxidant activity exhibited by the extract using three different methods involved the utilization of the total polyphenol content assay, the ferric reducing power assay and 2, 2-diphenyl-1-14 picrylhydrazyl (DPPH) assays. The results revealed that the Tulsi leaf extract (TLE) exhibited significantly higher antioxidant activity when compared to the Tulsi stem extract (TSE) in all the performed assays. The higher content of phenolics in TLE may have contributed to its superior antioxidant activity. The HPLC (high performance liquid chromatography) analysis of TLE revealed the presence of eugenol, active compound for several therapeutic properties. These findings provide an understanding of the bioactive compounds present in Tulsi extracts and their potential antioxidant benefits.

Sweet potato whitefly (SPW), Bemisia tabaci, is the most serious pest of greenhouse tomato as a vector of tomato yellow leaf curl virus since 2008 in Jeju. This study was conducted for within-plant distribution of SPW nymphs on leaves and the characteristic of spatial distribution of SPW adults using by yellow-color sticky trap in greenhouse-grown tomato plants. The nymphs of SPW were mainly distributed on leaves of mid-lower stratum in three stratum of tomato plant. They were also more distributed on three to four leaflets from basal part in a leaf. Ten plots and three plants per plot were appropriated to estimate of mean density of SPW nymph using by visual inspection in a tomato greenhouse. The more SPW adults were caught on horizontally placed sticky trap above 50～80 cm than vertically placed sticky trap above tomato canopy. The horizontal direction trap should be placed in opened site. SPW adults were shown the aggregated distribution pattern using by Taylor’s power law (TPL) and Iwao’s patchiness regression (IPR) model which are commonly used for spatial distribution pattern analysis. TPL was showed better description than IPR for spatial distribution pattern of SPW adults. The required number of trap tended to decrease according to increase the mean density of SPW adult

Entomopathogenic fungus Aschersonia aleyrodis naturally occurred on citrus whitefly, Dialeurodes citri nymph was often observed in organic citrus orchards, Jeju. The genus Aschersonia is also known to be toxic against scale insects and other pests. However, little is known about artificial media for mass production of spores of Aschersonia species. Grains are excellent sources of media for mass conidia production of various entomopathogenic fungi. The yeast extract, which converts carbohydrates to carbon dioxides and alcohols, contains a large amount of vitamin B complexes which facilitate the carbohydrate metabolism. The more yeast extract content the more conidia production on artificial medium made from commercial corn flour and corn gluten feed. The number of conidium produced on oat, millet, sorghum, and unhulled barley medium containing 1% yeast extract were 1.8, 1.8, 1.6, and 2.1×1010/plate (90mm × 15mm), respectively. However, the greatest yeast effect among four media showed appeared on sorghum medium, which produced 25 times higher spore production than sorghum alone. Furthermore, the conidia from solid sorghum medium could be easily harvested with cell scraper.

Aschersonia aleyrodis was well-known to be a biological control agent for citrus whitefly, Dialeurodes citri. This entomopathogenic fungus is naturally occurred in organic farming citrus orchards in Jeju. Both lime-sulfur and Bordeaux mixtures are extensively used today to control citrus diseases like citrus melanose and citrus scab, especially in organic farming pest management program. The high concentrated lime-sulfur is also used for pest control such as pink citrus rust mite and scale insects. This study was focused to test the conidial germination and sporulation of Aschersonia aleyrodis on potato dextrose agar (PDA) medium containing different concentrations of two fungicides. The conidia of Aschersonia aleyrodis grown on PDA mixed with commercial bordeaux mixtures, CM150-505, at dilution rate 1:200 (water : bordeaux mixture) were well-germinated but not sporulated at all. On the other hand, Aschersonia aleyrodis did not sporulate and germinate on lime sulfur treated PDA medium even at extremely low dilution rate 1:2,048,000 (water : lime sulfur). However, when the mycelial cells grown at 25o C for at least 7 days at soluble starch-tryptone medium were added to PDA, they were well-sporulated even at high dilution rate 1:100 (water : lime sulfur). This result suggested that the spore mixtures of Aschersonia aleyrodis should be applied to field quite long after lime-sulfur spray.

Beet armyworm (BAW), Spodoptera exigua (Hübner), is a polyphagous lepidopteran pest mainly distributed in tropical and subtropical regions. BAW are known to migrate long distances to find suitable host plants and environmental condition. The possibility of its overwintering in temperate regions has been suspected. This study was conducted for investigating overwintering and phenology of BAW using by sex pheromone trap in Jeju during 2007 to 2011. BAW was able to overwinter at pupae stage regardless of temperature of winter season in Jeju. The times of BAW caught first on traps were different by surveyed years - early March in 2007, middle March in 2008 and 2011 and early April in 2009 and 2010. The times of BAW caught on trap tended to be more dependent on temperature variation during on November and December than on mean temperature of winter season. The peak season of adults of the overwintering generation was early to middle of May. The results of seasonal periodicity of BAW monitored by sex pheromone trap during 2009 and 2010 indicated that five generations were passed in Jeju. The peak season of 1st generation was on middle of April, 2nd generation on middle of July, 3rd generation on early of August, 4th generation on late of August and 5th generation on middle of September. There were similar patterns by different above sea levels except the season of overwintering generation adults occurrence (March to May).

Arrowhead scale, Unaspis yanonensis, is a serious scale insect pest of citrus in Jeju. The sticky taping of 1.0 cm diameter twig was a good survey method for arrowhead scale crawler. There are three times crawler occurrence season - late May to early July, late July to middle September and late September to late October. But the third occurred crawlers are all died during overwintering in open-field groves. This study was conducted to provide information on efficient sampling plan for arrowhead scale within the tree. Twig and fruit was fit for secondary sample unit by two-stage variance analysis. Both sample number per tree (primary sample unit) was eight twigs or fruits. Taylor’s power law was better described the distribution characteristic of arrowhead scale than Iwao’s patchiness regression. The slope of both linear regressions was greater than “1” which means aggregative distribution pattern. Minimum sample size to estimate the density was calculated using by two parameters of Taylor’s power law. To estimate the mean density on twig and fruit by binomial sampling plan, the optimum tally threshold was 5 and 7, respectively.