• The Plant Pathology Journal
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• v.32 no.4
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• pp.290-299
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• 2016

Strawberry bacterial angular leaf spot (ALS) disease, caused by Xanthomonas fragariae has become increasingly problematic in the strawberry agro-industry. ALS causes small angular water-soaked lesions to develop on the abaxial leaf surface. Studies reported optimum temperature conditions for X. fragariae are $20^{\circ}C$ and the pathogen suffers mortality above $32^{\circ}C$. However, at the nursery stage, disease symptoms have been observed under high temperature conditions. In the present study, results showed X. fragariae transmission was via infected maternal plants, precipitation, and sprinkler irrigation systems. Systemic infections were detected using X. fragariae specific primers 245A/B and 295A/B, where 300-bp and 615-bp were respectively amplified. During the nursery stage (from May to August), the pathogen was PCR detected only in maternal plants, but not in soil or irrigation water through the nursery stage. During the cultivation period, from September to March, the pathogen was detected in maternal plants, progeny, and soil, but not in water. Additionally, un-infected plants, when planted with infected plants were positive for X. fragariae via PCR at the late cultivation stage. Chemical control for X. fragariae with oxolinic acid showed 87% control effects against the disease during the nursery period, in contrast to validamycin-A, which exhibited increased efficacy against the disease during the cultivation stage (control effect 95%). To our knowledge, this is the first epidemiological study of X. fragariae in Korean strawberry fields.

• Proceedings of the Ginseng society Conference
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• 1974.09a
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• pp.147-152
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• 1974

• Proceedings of the Korean Society of Crop Science Conference
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• 2019.09a
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• pp.23-23
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• 2019

• Current Research on Agriculture and Life Sciences
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• v.19
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• pp.23-29
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• 2001

This study was carried out to develop a seedling raising method without nursery soils in automatic raising facility of rice seedlings for machine transplanting. Pre-germinated seeds were sowed on the seed trays with three different seats such as paper seat, corrugated board, and polyethylene film instead of nursery soils. The growth characteristics of the seedlings for 20 days after sowing were compared with that of a conventional standard raising method with nursery soils. There was no difference in plant height of 10-day old seedlings among the different nursery methods, but the plant height of seedlings grown for 15 days after sowing in the trays with fivefold newspaper and nursery soils was significantly taller than those on other nursery conditions. Dry weight of seedlings grown in the tray with fivefold newspaper bottom was heavier than those in nursery trays with a corrugated board and a piece of polyethylene film. The seedlings grown in a nursery tray with fivefold newspaper showed better seedling quality and root-mat formation compared with the other nursery trays. This result suggests that the healthy seedlings for machine transplanting can be raised in the paper-sheet tray without nursery soils. The labour hours and cost required for the soil-free method using paper was reduced by about 49.3% and 26.6%, respectively, compared with the semi-adult seedling on nursery soils.

• Korean Journal of Medicinal Crop Science
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• v.25 no.4
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• pp.238-243
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• 2017

Background: The production method of ginseng seedlings for ginseng cultivation is very important to ensure healthy rooting system as well as high quality, and yield of the resultant plants. This study was carried out to compare the growth characteristics of 2-year-old ginseng plants that were produced from seedlings grown in self soil nursery (SSN), nursery soil (NS) or hydroponic culture (HC). Methods and Results: The shading prop used was composed of four-layered 4 polyethylene (blue 3 + black 1) shade screen. The management of main field was done by inserting oil cake (1,200 kg/10 a) and then allowing Sudan grass to grow for a year. Seedling transplantation was carried out on April 6. Root growth was measured on October 25. Root weight was observed to be excellent at 6.0 g, following SSN transplantation. Root length was 21.2 cm for HC seedlings, but these plants had a physiological disorder (i.e., rusty root), in 83.5% plants of this treatment. The ratio of PD/PT (protopanaxadiol saponins / protopanaxatriol saponins) was higher in NS seedlings. Plant analysis revealed that Fe content was lower in HC seedlings with high rustiness. The growth of 2-years-old ginseng was different following these varying seedling cultivation methods, but seedlings from NS were not different from those grown in SSN. Conclusions: For the propagation of 2-year-old ginseng plants, NS seedlings may be a good substitute for SSN seedlings.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.43-52
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• 1988

One-year-old seedlings of Ginkgo biloba were treated with various simulated acid rains(pH 2.0, pH 3.0, pH 9.0 and pH 5.0) to examine the effects of simulated acid rain on the chemical properties of the tested soil. The seedlings were grown in a pot($4500cm^3$)containing one of three different soils(nursery soil, mixed soil and sandy soil). Simulated acid rain was made by diluting sulfuric and nitric acid solution($H^1SO^4$ : $HNO^3$ =3 : 1, V/V) with tap water and tap water(pH 6.4), and treated by 5mm each time for three minutes during the growing seasons(April to October 1985). Acid rain treatments were done three times per week to potted seedlings by spraying the solutions. The chemical properties of potting media were compared among three soil types as well as among the various pH levels. The results obtained in this study were as follows : 1. Exchangeable calcium and magnesium contents and base saturation of the soil decreased with decreasing pH levels of acid rain, and their decreasing rates were as follows : sandy soil was the highest, followed by mixed and nursery soils, However, exchangeable aluminum content rather increased as the pH levels decreased. 2. Available phosphate in the soil decreased as the pH levels of acid rain decreased. Its content increased in nursery soil, compared with those before acid gain treatment, Gut decreased in mined and sandy soils. 3. Soil sulfate and nitrate contents increased remarkably as the pH levels decreased, and the only significant difference in the sulfate was found among the pH levels. Soil sulfate content was the highest in nursery soil, followed by mixed and sandy soils.

• Journal of Forest and Environmental Science
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• v.36 no.4
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• pp.281-289
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• 2020

The study was conducted to observe the effects of compost of faecal sludge (FSC) and food waste (FWC) on seed germination and initial growth performance of Acacia auriculiformis and Swietenia mahagoni seedlings at the nursery of Chittagong University, Bangladesh. Before sowing the seeds, different combinations of FSC and FWC were incorporated with nutrient-deficient natural forest soils. Seed germination and growth parameters of seedlings were recorded after two, three and four month of seed sowing. We observed that seed germination (%) and seedlings growth parameters varied significantly (p<0.05) in the soil added with FSC and FWC in comparison to control. The highest germination was observed 88.89% for A. auriculiformis in combination of soil and FSC at 3:1 and 92.59% for S. mahagoni where soil combined with FWC at 4:1. The seedling biomass and other growth parameters of A. auriculiformis and S. mahagoni was also observed with combinations of soil with FSC 3:1 and soil with FWC 4:1. Therefore, the study revealed that the compost of both FS and FW can be a good soil conditioner for the initial growth of forest seedlings and the proven combinations can help to grow quality seedlings in the nursery.

• The Korean Journal of Soil Zoology
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• v.6 no.1_2
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• pp.37-44
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• 2001

Scarabaeids and white grubs were investigated at Halla arboretum and nursery in Jeju province in 1999 and 2001. Scarabaeid pests were surveyed from 14 tree species of 12 families at Halla arboretum in Jeju in March, 1999 and from 55 species of 27 families in March and September, 2001 and from Taxus cuspidata at nursery in Seoguipo in March, 1999 and 18 tree species of 9 families at the same nursery in March and September, 2001. Six species of white grubs and scarabaeids were collected from Halla arboretum. At Halla arboretum, Holotrichia niponensis was collected from 28 tree species of 21 families, H. diomphalia from 27 tree species of 20 families, and an unidentified white grub from 27 tree species of 19 families. Maladera orientalis was collected from 4 tree species of 4 families and Aphodius sp. and Adoretus tenuimaculatus from Punica granatum and Carpinus sieboldiana. At Halla nursery in Seoguipo, H. niponensis were collected from 9 tree species of 6 families and H. diomphalia from 10 tree species of 6 families. White grub of Minela testaceopes was collected from Ternsstraemia japonica. H. niponensis, H. diomphalia and an unidentified white grub were dominant species out of collected white grubs and scarabaeids and these were collected from Cinamomum camphrora. H. niponensis was the most serious pest on T. cuspidata.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.39-45
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• 1998

As a basic research for developing a sludge application technique in forestry, this study was conducted to investigage a reasonable amount and period of sludge to be applied onto forest nursery of Acer palmatum Thunb. The paper mill sludge was used for the study, and ammonium nitrate was treated to some of them to reduce the C/N ratio lower than 40. The maximum amount of applied sludge was 7ton/ha/year, and they were spread on spring and on late summer. The sludge application did not stimulate early growth of the trees during a year. Since there was no significant changes in soil chemical properties, the amount of applied sludge was thought to be too little to result in a significant role for tree growth. However, the soil water showed significant increase of Cu when the activated sludges were applied during late summer. Thus, the time of application need to be determined cautiously with considering the risk of ground water contamination. In conclusion, if we set a goal from the view point of long-term concept such as forest productivity rather than to get a short-term product, the uncomposted sludge in small amount during growing season might be considered to be applied on forest nursery.

• Korean Journal Plant Pathology
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• v.10 no.2
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• pp.112-118
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• 1994

Forth microbial isolates out of 167 isolates from the soil of controlled cultivation areas inhibited mycelial growth of Rhizoctonia solani AG2-1 causing the strawberry bud rot in vitro. Among the isolates, Kr013 and Kr020 showed suppressive effect to R. solani AG2-1 on seedlings of chinese cabbage treated by root immersion, charcoal carrier granule and drenching on 1.0% infested soil in pot. Furthemore, the corresponding effect was also revealed when the charcoal carrier granule of the isolates were treated on the seedling of strawberry that were planted on the planting hole in pot. To examine the effects of biological control in green house, it had been tested the infection rates by using two different treatments. First, the strawberry runner were planted on the nursery soil mixed with 20% charcoal carrier granule of Kr013 and Kr020 isolate respectively, and grown for 20 days before transplanting. Then the young plants form the mother plant were separated and transplanted on the 1.0% infested soil. Another method was that the charcoal carrier of Kr013 and Kr020 isolates applied to planting hole of 1.0% infested soil just before transplanting. Then the young plants were grown for 20 days on the sterilized nursery soil before transplanting. From the results, the effects of biological control was significantly higher on former treatment (e.g. the infection rates were 7.3 and 5.7%, respectively) than on the latter treatment (e.g. the corresponding value were 16.7 and 15.7%, respectively). The antagonistic isolates of Kr013 and Kr020 were respectively identified as Pseudomonas cepacia with the similarity of 55.0% and 60.0% by using the Biolog GN Microplate system.