• Korean Journal of Agricultural and Forest Meteorology
• /
• v.24 no.1
• /
• pp.35-47
• /
• 2022

Expansion of potato production areas can improve the food security in North Korea because the given crop has less requirements for agricultural materials and facilities. The Global Agro-Ecological Zones (GAEZ) model, which was developed to evaluate climate suitability under different cultivation conditions, was used to identify potential areas for the potato production. The spatial estimates of crop suitability under low and high input management conditions were downloaded from the GAEZ data portal. The values of suitability were obtained at the potato occurrence sites retrieved from the Global Biodiversity Information Facility (GBIF) database. The suitable areas for the potato production were identified using a threshold value derived from the suitability estimates at the occurrence sites. It was found that 90% of the occurrence sites had the suitability index value >3,333, which was set to be the threshold value. The suitable areas in North Korea were summarized by province and county. Rice cultivation areas were excluded from the analysis. The reported relative acreage of potato production was better represented by the suitable areas under the low input management options than the high input conditions. The suitable areas also had a similar distribution to the reported acreage of potato production by county. These results indicated that the GAEZ model would be useful to identify the candidate production areas, which would facilitate the increases in potato production especially under future climate conditions. Furthermore, monthly maps of crop suitability can be used to design cropping systems that would improve crop production under the limited use of agricultural materials and facilities.

• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.37-37
• /
• 2003

Rice is one of the most important crop in the world and is a major export of Thailand. Optical sensors are not useful for rice monitoring, because most cultivated areas are often obscured by cloud during the growing period, especially in South East Asia. Spaceborne Synthetic Aperture Radar (SAR) such as RADARSAT, can see through regardless of weather condition which make it possible to monitor rice growth and to retrieve rice acreage, using the unique temporal signature of rice fields. This paper presents the result of a study of examining the backscatter behavior of rice using multi-temporal RADARSAT dataset. Ground measurements of paddy parameters and water and soil condition were collected. The ground truth information was also used to identify mature rice crops, orchard, road, residence, and aquaculture ponds. Land use class distributions from the RADARSAT image were analyzed. Comparison of the mean DB of each land use class indicated significant differences. Schematic representation of temporal backscatter of rice crop were plotted. Based on the study carried out in Pathum Thani Province test site, the results showed variation of sigma naught from first tillering vegatative phase until ripenning phase. It is suggested that at least, three radar data acquisitions taken at 3 stages of rice growth circle namely; those are at the beginning of rice growth when the field is still covered with water, in the ear differentiation period, and at the beginning of the harvest season, are required for rice monitoring. This pilot project was an experimental one aiming at future operational rice monitoring and potential yield predicttion.

• Korean Journal of Organic Agriculture
• /
• v.6 no.2
• /
• pp.127-140
• /
• 1998

Organic farming excludes any use of the herbicide. The present paper reviews what can be done for effective weed control with existing weed control technology by farmers crop-ping paddy rice, field crops, vegetables, and fruit trees. If condition of the crop-land-al-lows diversified rotational use of the paddy land as paddy and upland field would minimize weed problem. Practising this is limited in acreage due to extremely limited governmental investment to the land for the purpose. Secondly, rotation of crops in the upland field breaking life cycles of various weeds adapted to each crop should reduce the weed problem. This is also limited as only a few crops are making the farmer profitable. In addition climate and tolerance of crops to high and low temperature. Monsoon rains and poor drainage restrict the freedom of choice. For any crop land year-round multiple cropping in denser planting shall lessen the weed problem, this multiple cropping practiced by 1960s has been abandoned due to laborshortage and increased production cost. Deep flooding the rice is impractical at present in Korean. Mulching crop with transparent, black , or combinated polyethylene sheet, hs been in-creasingly used. Progresses in development and use of mulch with allelopathic crop residues. inexpensive paper mulch, allelopathic crop residues, inexpensive paper mulch, allelopathic crop cultivar development, recently developed ex-perimental weeding machinaries, flamers, microbial herbicides, biological control organisms, soil sterilization techniques have been critically reviewed for their adoption into existing in-tegrated weeding system. Unfortunately, information on cost-benifit, and labor-benefit, for the various methods above mentioned are lacking. Urgent need for the research on rational weeding in organic farming, and herbicide low-input farming is emphasized.

• Research in Plant Disease
• /
• v.10 no.1
• /
• pp.1-7
• /
• 2004

The year of 2003 was characterized as a cool humid year. Low temperature and frequent rains were continued during March to July, resulting in 1.6 times higher rainfalls and 32％ less sunshine period compared to the average yean Due to 2003's climatic condition, rice blast, and bacterial leaf blight occurred severely. Higher rainfalls caused severe epidemic of phytophthora disease and, in case of red-pepper, 55％ of cultivation acreage was devastated by the disease over the country. Besides, crop diseases which become severe under cool-humid conditions, such as gray mold, sclerotinia rot, downy mildew, increased significantly compared to the previous year. In fruit trees, brown spot of apple, and pear scab occurred severely causing much yield loss.

• Journal of Ginseng Research
• /
• v.1 no.1
• /
• pp.13-18
• /
• 1976

Production of Panax ginseng in Korea has been increased tremendously in the last two decades, the acreage and number of growers hating been spread across the country. Improvement of variety, on the other hand, has been seldom carried out during this period, rendering the ginseng growing risky and hazardous. Breeding work with such perennial crop as ginseng if rather time-consuming, and there are few genesources to start with. Authorities concerned with ginseng Production pay hwy little attention to breeding researches for nimbus of reasons. As this crop is cultivated over the entire area of Korea. Breeding work cannot be allowed to delay forth. In the precut article, improvement of ginseng was discussed from the view point of two different categories of brooding concept: (1) conventional breeding and (2) breeding based on the somatic tell genetics.

• Journal of Korean Society of Rural Planning
• /
• v.26 no.3
• /
• pp.25-38
• /
• 2020

The purpose of this study is constructing a regional-level crop acreage choice model incorporating the impacts of producer risk aversion, and applying the constructed model to the Korean policy that promotes rice paddy conversion into non-rice crop fields. The study adopts the approach of Paris (2018) which estimates the absolute risk aversion coefficient inside of a positive mathematical programming model. A panel data set of 143 cities/counties is used for the empirical study where agricultural land in each region is allocated to 8 crops. Our estimated absolute risk aversion coefficients are smaller than those of Paris (2018), but are a little bit larger than those of the existing Korea studies based on survey or econometric methods. We found that there are close relationships among the estimated risk aversion, regional characteristics, and farming patterns. We also found that incorporating the estimated risk attitudes results in substantial differences in the impacts of the rice paddy conversion policy.

• Korean Journal of Medicinal Crop Science
• /
• v.12 no.1
• /
• pp.43-46
• /
• 2004

In genus Angelica, three species have been used and cultivated for medicinal material in orient, A. gigas in Korea, acutiloba in Japan and sinensis in China. A. gigas (Chamdangui) is different from A. acutiloba or A. sinensis in the contents chemical components and their efficacious. In Korea, in particular, A. acutiloba has been cultivated in a small acreage from several decades ago, and recently A. sinensis has been trying to cultivate. A trial of adaptation and cultivation of the three species was performed in different altitudinal regions such as Suwon (50 m of sea level), Jinbu (500 m of sea level) and Taebak (700 m of sea level). A. gigas and acutiloba grew and produced roots successfully at all locations, but A. sinensis could grow only at high altitudinal region, Taebaek. A. sinensis survived 70.3% at Taebaek, but only 45.2% at Jinbu and 3.6% at Suwon. The dry root yield of A. sinensis was as low as 1,600 kg/ha at Taebaek and 1,270 kg/ha at Jinbu comparing farmers' average root yield of A. gigas, 3,000 kg/ha however, no root could be harvested at Suwon. The results, showed it was that A. sinensis could not grow at low altitudinal plane area except high altitude area in Korea. Even though it could grow, the root yield was too low to support the income.

• Korean Journal of Soil Science and Fertilizer
• /
• v.11 no.4
• /
• pp.283-295
• /
• 1979

A new Farmland Expansion and Development Promotion Law was enacted in 1975. This law authorizes the Government to undertake development within a declared "reclamation area", wherever the land owners are unable to do so. In order to give additional impetus to conversion of waste hilly land into productive farmland, these hilly land development projects were conducted as large scale scheme which include soil fertility improvements such as the application of lime and phosphate. Farmland Expansion and Development Promotion Corps has attempted to undertake annual farm surveys in order to obtain some information about hilly land agriculture and farming operations within the reclamation project areas since 1976. As survey data accumulates, more and more clear picture of hilly land farming come to appear and enable us to conduct in-depth study. Effects of such upland reclamation include converting of previously unproductive slopeland into cultivable farmland for lucrative and commercial farming or food production. Furthermore, idle or marginal resources such as farm labor, equipment and compost would be fully employed. Socio-economic effects would include increases in land value and attitude change of farmers. On the other hand the preservation of natural environments might be damaged to the some extend by the projects. As shown in Table 7, the average farm size increased from 3,156 pyeong($3.3m^2$) to 5,562 pyeong, a 76.2% increase. The proportion of small farms with less than I ha dropped from 59.8% to 34.4%, but that of the large farms over 2 ha rose from 13.1% to 32.0% (See Table 8). The survey results indicate that as the farming on reclaimed uplands become time-honored, the acreage devoted for food crop production decreases against the economic crop growing acreage (see Table 6). For example, in the case of uplands reclaimed in 1972, the ratio of food crop acreages decreased from 99.7% in 1972 to 62.5% in 1977, whereas that of economic crop acreages increased from 0.3% in 1972 to 37.5% in 1977. The government used to actively encourage the farmers to carry out food crop production in the reclaimed upland targting toward the realization of self-sufficiency in food grains. It is, however, apparent that the farmers did hardly take the government advises as far as their economic interest were concerned. Yield per 10a. of various crops from the reclaimed uplands by year were surveyed as seen in Table 12. On the average, barley production in the reclaimed areas achieved 83.3% of the average unit yield from the existing upland in its 5 th year. Soybean yields showed a modest increase from 64% in the first year to 95%, in the 5 th year. In contrast, economic crops such as red pepper, totacco and radish achieved their maximum target yields in 3 years from starting to cultivate on the reclaimed farms. In order to test the post economic viability, an economic analysis was performed for each of selected subprojects on the basis of the data obtained through survey. The average actual internal economic rate of return on upland reclamation investments was found to be 20.3% which exceeded other types of projects of land and water development such as tidal land reclamation, irrigation or paddy rearrangement. The actual IRRs of subcategories of upland reclamation projects varied from 17.9% to 21.4% depending upon the kinds of cropping system adopted in each reclaimed areas such as food, economic, fruit or forage crops.

• The Korean Journal of Pesticide Science
• /
• v.17 no.1
• /
• pp.41-49
• /
• 2013

This study was performed to investigate the cultivation pattern and perception, such as safety awareness, of environmentally-friendly organic materials among Korean farmers. The main reason for participation of the environmentally-friendly agriculture was for the production of safe agricultural crops. Compared to small-acreage farmer were more aware about the safety of environmentally-friendly organic materials to the subjects. Accordingly, 23.6% among the respondents with environmentally-friendly agriculture certification experienced the adverse effect by using the environmentally-friendly organic materials, compared to 33.8% of among the respondent without the certification. The experienced type of adverse effects consisted mainly 'eyes itch', 'hands and feet itch' and 'fatigue'. Also, respondent experiencing the adverse effects by using the environmentally-friendly organic materials more comply with the usage standard as how to use marked in wrapping paper, compared to the respondent without experiencing the adverse effects, which indicate that the compliance with the usage standard as how to use marked in wrapping paper is closely related the experience the adverse effects. Further study should be needed for more precise investigation of comment for the farmers in order to suggest the effective improvement in terms of policy or education for their safety.

• The Plant Pathology Journal
• /
• v.33 no.3
• /
• pp.229-237
• /
• 2017

Rye (Secale cereale L.) serves as an alternative host of Pyrenophora tritici-repentis (PTR) the cause of tan spot on wheat. Rye is cultivated as a forage or cover crop and overlaps with a significant portion of wheat acreage in the U.S. northern Great Plains; however, it is not known whether the rye crop influences the evolution of PTR races. We evaluated a global collection of 211 rye accessions against tan spot and assessed the diversity in PTR population on rye in South Dakota. All the rye genotypes were inoculated with PTR races 1 and 5, and infiltrated with Ptr ToxA and Ptr ToxB, at seedling stage. We observed 21% of the genotypes exhibited susceptibility to race 1, whereas, 39% were susceptible to race 5. All 211 accessions were insensitive to both the Ptr toxins. It indicates that though rye exhibits diversity in reaction to tan spot, it lacks Ptr ToxA and ToxB sensitivity genes. This suggests that unknown toxins or other factors can lead to PTR establishment in rye. We characterized the race structure of 103 PTR isolates recovered from rye in South Dakota. Only 22% of the isolates amplified Ptr ToxA gene and were identified as race 1 based on their phenotypic reaction on the differential set. The remaining 80 isolates were noted to be race 4. Our results show that races 1 and 4 are prevalent on rye in South Dakota with a higher frequency of race 4, suggesting a minimal role of rye in the disease epidemiology.