• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.67 no.4
• /
• pp.285-295
• /
• 2022

The trapping efficacy of five commercially available sex pheromones manufactured in Korea, the Netherlands, North America, China, and Costa Rica was evaluated to determine the population dynamics of Spodoptera frugiperda and Mythimna loreyi and their relationships with the weather parameters of maize fields in Miryang, Gyeongnam Province, Korea in 2019. The results show that the sex pheromone manufactured in Costa Rica were more efficient at capturing S. frugiperda and M. loreyi than those manufactured in other countries. The lowest number of S. frugiperda moths were captured using sex pheromones manufactured in the Netherlands. We noted that more than four population peaks of both the moth species and weather parameters influenced the moth population dynamics in Miryang. A positive relationship was observed between the population of S. frugiperda and weather parameters, such as mean temperature, rainfall, and relative humidity, for sex pheromones manufactured in Korea. Furthermore, a positive relationship was recorded between the population of M. loreyi and wind speed for the sex pheromone manufactured in Korea. The results of this study suggest that the sex pheromones manufactured in Costa Rica are the best solution for the efficient capture of S. frugiperda and M. loreyi under typical weather conditions in the southern parts of Korea. In addition, the outcomes of this study are discussed in terms of population dynamics and integrated pest management for S. frugiperda and M. loreyi as alternatives to chemical management by maize producers. Further studies related to the continuous improvement in the capture efficiency of both moth species using sex pheromones are now needed.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 1988.02a
• /
• pp.98-99
• /
• 1988

• Proceedings of the Korean Society of Crop Science Conference
• /
• 1992.05a
• /
• pp.62-63
• /
• 1992

• Korean Journal of Remote Sensing
• /
• v.37 no.4
• /
• pp.789-802
• /
• 2021

Synthetic Aperture Radar (SAR) at C-band is an ideal remote sensing system for crop monitoring owing to its short wavelength, which interacts with the upper parts of the crop canopy. This study evaluated the potential of dual polarimetric Sentinel-1 at C-band for monitoring rice phenology. Rice phenological variations occur in a short period. Hence, the short revisit time of Sentinel-1 SAR system can facilitate the tracking of short-term temporal morphological variations in rice crop growth. The sensitivity of SAR backscattering coefficients, backscattering ratio, and polarimetric decomposition parameters on rice phenological stages were investigated through a time-series analysis of 33 Sentinel-1 Single Look Complex images collected from 10th April to 25th October 2020 in Gimhae, South Korea. Based on the observed temporal variations in SAR parameters, we could identify and distinguish the phenological stages of the Gimhae rice growth cycle. The backscattering coefficient in VH polarisation and polarimetric decomposition parameters showed high sensitivity to rice growth. However, amongst SAR parameters estimated in this study, the VH backscattering coefficient realistically identifies all phenological stages, and its temporal variation patterns are preserved in both Sentinel-1A (S1A) and Sentinel-1B (S1B). Polarimetric decomposition parameters exhibited some offsets in successive acquisitions from S1A and S1B. Further studies with data collected from various incidence angles are crucial to determine the impact of different incidence angles on polarimetric decomposition parameters in rice paddy fields.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2006.04a
• /
• pp.286-287
• /
• 2006

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2000.11a
• /
• pp.12-27
• /
• 2000

During the recent decades, he problem of climate variability and change has been in the forefront of scientific problems. The objective of this study was to assess the impact of climate variability on crop growth and yield. The growth duration was the main impact of climate variability on crop yield. Phyllochronterval was shortened in the global worming situations. A simple model to describe developmental traits was provided from heading data of directly seeded rice cultivars and temperature data. Daily mean development rate could be explained by the average temperature during the growth stage. Simple regression equation between daily mean development rate(x) and the average temperature(y) during the growth period as y = ax + b. It can be simply modified as x = 1/a $\ast$ (y-b). The parameters of the model could depict the thermo sensitivity of the cultivars. On the base of this model, the three doubled CO2 GCM scenarios were assessed. The average of these would suggest a decline in rice production of about 11% if we maintained the current cultivars. Future cultivar's developmental traits could be suggested by the two model parameters.

• Journal of Crop Science and Biotechnology
• /
• v.10 no.3
• /
• pp.133-140
• /
• 2007

Protein characteristics of Korean wheat were evaluated to determine the effects of protein content and quality on processing and textural properties of white salted noodles compared to US wheat flours with various wheat classes and commercial flours for making noodles. Protein quality parameters, which were independent of protein content and included SDS sedimentation volume with constant protein weight, mixograph mixing time and proportion of 50% 1-propanol insoluble protein, of Korean wheat flours with 2.2+12 subunits in high molecular weight glutenin subunit compositions were comparable to those of commercial flours for making noodles. Parameters related to noodle making, including optimum water absorption, thickness and color of noodle dough sheet, correlated with protein content and related parameters, including SDS sedimentation volume with constant flour weight, mixograph water absorption and gluten yield. No significant relationship was found in protein parameters independent of protein content. Hardness of cooked noodles from Korean wheats was lower than that of US wheat flours compared to similar protein content of commercial noodle flours. Adhesiveness, springiness and cohesiveness of cooked noodles from Korean wheats were similar to US wheat flours. Hardness of cooked noodles correlated with protein content and related parameters.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2019.09a
• /
• pp.19-19
• /
• 2019

It is necessary to maintain stable crop productions under the unsuitable environments, because the drought and flood may be frequently caused by the global warming. Therefore, it is agent to improve the crop growth model corresponded to soil moisture status. Chili pepper (Capsicum annuum) is one of the useful crop in Asia, and then it is affected by change of precipitation in consequence drought and flood occur however crop model to evaluate water stresses on chili pepper is not enough yet. In this study, development of crop model under different soil moisture status was attempted. The experiment was conducted on the slope fields in the greenhouse. The water level was kept at 20cm above the bottom of the container. Habanero (C. chinense) was used as material for crop model. Sap bleeding rate, SPAD value, chlorophyll content, stomatal conductance, leaf water potential, plant height, leaf area and shoot dry weight were measured at 10 days after treatment (DAT) and 13 DAT. Moreover, temperature and RH in the greenhouse, soil volume water contents (VWC) and soil water potential were measured. As a result, VWC showed 4.0% at the driest plot and 31.4% at the wettest plot at 13 DAT. The growth model was calculated using WVC and the growth analysis parameters. It was considered available, because its coefficient of determination showed 0.84 and there are significant relationship based on plants physiology among the parameters and the changes over time. Furthermore, we analyzed the important factors for higher accuracy prediction using multiple regression analysis.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2022.10a
• /
• pp.133-133
• /
• 2022

Temperature is a crucial environmental factor for rice cultivation due to the climate change and can influence the rice growth and development. Therefore, the effect of temperature on plant growth characters was examined during the vegetative stage. Plants were grown under three different temperatures: 23℃/13℃ for 18℃, 26℃/16℃ for 21℃ and 29℃/19℃ for 24℃ in the phytotron. The temperature was treated after transplanting and ended in early panicle initiation stage. Heading date of the two varieties were strongly affected by the temperature and were delayed in the 18℃. The plant height in the 18℃ was 21 % shorter than the 21℃ and 24℃ and the tiller and leaf number were increased in the 18℃. All the growth rates of the characters were the slowest in 18℃. The stem dry weight was significantly increased in 18℃. Nitrogen content was increased in the leaves of 18℃ whereas available phosphate and potassium content was found to be increased in the stems of 21℃ and 24℃. OsNRT 2.1 was overexpressed in the leaves and stems of 18℃ and OsNRT2.3a could be expressed in 18℃ and 21℃ temperatures whereas more expressed in 21℃. OsPT1 and OsPT6 could be expressed in the leaf of 18℃ and 24℃ but could be expressed in the stem of 18℃. OsHAK1 and OsHAK5 could be overexpressed in the leaves and stems of 18℃. For hormone, OsCKX2 gene was found to be up regulated in the leaves of 18℃ and OsIAA1 gene could be expressed more in the stem of 24℃.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2021.10a
• /
• pp.103-103
• /
• 2021