• Korean Journal of Soil Science and Fertilizer
• /
• v.25 no.3
• /
• pp.270-274
• /
• 1992

This study was observed to find out the relationship of soil microorgaism physico-chemical properties and yields on the continuous cultivation of peanuts soil in the difference 20 farmes field located in Gochang, Chonbuk area. The results obtained was summarized as follows : 1. Soil hardness and volume of soild and liquid of peanut continuous cultivation soil were higher than those of one year cultuvation. 2. The exceeding optimum level of phosphorus and potassium appeared factors affecting and reduction of peanut continuous cultivation soil. 3. Number of microorgaisms in continuous cultivation soil was high but the ratio of bacteria/fungi (B/F) and actinomycetes/fungi (A/F) ratio were low. 4. The number of soil nematodes in continuous cultivation soil were higher than that of alternative cultivation soil.

• Journal of Bio-Environment Control
• /
• v.13 no.1
• /
• pp.33-38
• /
• 2004

This experiment was conducted to screen the suitable rootstocks for the soil cultivation of paprika (Capsicum annuum L.) in highland. Sixteen kinds of rootstocks were grafted to the red colored 'Spirit' scion for the resistances to diseases like fruit lot (Phytophthora capsici) and bacterial wilt (Ralstonia solanacearum). Four varieties among the rootstocks, 'Tantandaemok', 'Skurt-S', 'AC 2258', and 'PST 8301' were selected for the high resistance to fruit rot of paprika. However non-grafted control plants were totally dead at five days after inoculation. Furthermore, seven varieties including 'Yeokgang', ;Tantandaemok', 'TE412', 'MC 4', 'PST VK', and 'PST NV' were selected for the high resistance to bacterial wilt. The grafting with pest resistant rootstocks could enhance the rhizophere environment through root fresh weight increase. High yielding rootstocks for paprica 'Spirit' were PST 8301, MC 4, and Wanggeun.

• Horticultural Science & Technology
• /
• v.30 no.5
• /
• pp.557-567
• /
• 2012

This study was conducted to achieve basal information for the development of tomato cultivars with disease resistances through marker-assisted backcross (MAB). Ten inbred lines with TYLCV, late blight, bacterial wilt, or powdery mildew resistance and four adapted inbred lines with superior horticultural traits were collected, which can be useful as the donor parents and recurrent parents in MAB, respectively. Inbred lines collected were evaluated by molecular markers and bioassay for confirming their disease resistances. To develop DNA markers for selecting recurrent parent genome (background selection) in MAB, a total of 108 simple sequence repeat (SSR) primer sets (nine per chromosome at average) were selected from the tomato reference genetic maps posted on SOL Genomics Network. Genetic similarity and relationships among the inbred lines were assessed using a total of 303 polymorphic SSR markers. Similarity coefficient ranged from 0.33 to 0.80; the highest similarity coefficient (0.80) was found between bacterial wilt-resistant donor lines '10BA333' and '10BA424', and the lowest (0.33) between a late blight resistant-wild species L3708 (S. pimpinelliforium L.) and '10BA424'. UPGMA analysis grouped the inbred lines into three clusters based on the similarity coefficient 0.58. Most of the donor lines of the same resistance were closely related, indicating the possibility that these lines were developed using a common resistance source. Parent combinations (donor parent ${\times}$ recurrent parent) showing appropriate levels of genetic distance and SSR marker polymorphism for MAB were selected based on the dendrogram. These combinations included 'TYR1' ${\times}$ 'RPL1' for TYLCV, '10BA333' or '10BA424' ${\times}$ 'RPL2' for bacterial wilt, and 'KNU12' ${\times}$ 'AV107-4' or 'RPL2' for powdery mildew. For late blight, the wild species resistant line 'L3708' was distantly related to all recurrent parental lines, and a suitable parent combination for MAB was 'L3708' ${\times}$ 'AV107-4', which showed a similarity coefficient of 0.41 and 45 polymorphic SSR markers.

• Korean Journal of Weed Science
• /
• v.32 no.2
• /
• pp.98-106
• /
• 2012

This research has been carried out to find out the highest effect on insecticidal, fungicidal and herbicidal activities in leaves, stem and tuber extracts of yacon (Smallanthus sonchifolius) and extraction methods such as water, boiling water and methanol. Characteristics of potential herbicidal components among extraction methods were investigated by solvent fractions such as hexane, chloroform, ethyl acetate, butanol, and water. Generally, methanol extract was the best on inhibition of germination rate, plant height, and root length in cucumber and barley. On the other hand, the inhibition effect on growth in cucumber and barley was the best in tuber among plant parts of yacon. Inhibition of germination rate, plant height, and root length in cucumber and barley in solvent fractions was the best in water fraction, but there were no differences in other fractions. Digitaria sanguinalis L. and Solanum nigrum L. by 5 and 10% extractions of yacon tuber were controlled by more than 70~80% and 95~100%, respectively. However, there was no inhibition effect on foliar treatment in cucumber and barley as affected by 5 and 10% extractions of yacon tuber. Mortality of green peach aphid (Myzus persicae Sulzer) was 50% at 3 days after treatment of 5% extracts of yacon leaves. Mortality of brown plant hopper (Nilaparvata lugens Stal) was only 24% in 5% extracts of stems and leaves with midrib, but was 57% in 5% extracts of leaves without midrib. There was no fungicidal effect on anthracnose (Colletotrichum truncatum), wilt disease (Fusarium oxysporum), verticillium wilt (Verticillium dahliae), bacterial blight (Xanthomonus oryzae) in 5% extracts of yacon leaves.