• Horticultural Science & Technology
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• v.34 no.3
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• pp.414-423
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• 2016

Growers in plug seedling production think that root media in which rockwool is a component has given rise to several environmental problems. Therefore, the demand for new materials as a substitute for rockwool has been increased. This study examined the possibility of cultivation of tomato plug seedlings using a newly developed growing medium with phenolic foam. Plug seeds of tomato cultivar 'Madison' were sown in four pellet-type growing media: Grodan rockwool (GRW), UR rockwool (URW), phenolic foam LC (LC) or phenolic foam LC-lite (LC-lite). Then, the seedlings were transplanted to the four cube-type growing media 19 days after sowing. Seeds were germinated in a growth chamber ($25{\pm}2^{\circ}C$, 80% relative humidity, and dark) for 4 days and then the seedlings were grown with a nutrient solution supplied by an overhead irrigation system in a greenhouse. Plant height, number of leaves, leaf area, and fresh or dry weight of tomato seedlings were the greatest for the seedlings transplanted to URW cube media after being grown on LC-lite pellets. Root grade was the greatest for the seedlings transplanted on LC or LC-lite cube media after being grown on LC pellets. Chemical properties of all media tested for tomato growth were maintained within a stable range, while physical properties of URW showed high values in container capacity, air space, and total porosity. These results demonstrated that the phenolic foam media were effective for seedling growth and can substitute for rockwool as a root medium.

• Journal of Bio-Environment Control
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• v.29 no.3
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• pp.245-251
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• 2020

This study was conducted to investigate the seedling qualities and growth of paprika according to various irrigation points (IPs) (30, 40, 50, 60 or 70%) compared to the weight of rockwool cube with 100% water content for raising seedlings of paprika. Growth degree of paprika seedlings was positively correlate with various irrigation points. In particular, paprika seedlings with IP 30-40% and IP 50-70% treatments were significantly higher than those with other treatments. Leaf area of seedlings was 50-100% wider in those with IP 50% and IP 40% treatments than those with other treatments, therefore dry weight was heavier in IP 30-60% treatments. The dry weight of more than IP 50% treatments had no significant differences. Leaf area (Y₁) had a significant relation with the irrigation point (x) as Y₁ = 48.311x + 133.7 (R² = 0.9116^⁎⁎). Also dry weight (Y₂) of the seedlings showed a linear regression equation as Y₂ = 0.1584x + 0.8616 (R² = 0.8853^⁎). Considering the leaf area and the dry weight of irrigation points for rising seedlings of paprika in this study, the optimum range of the irrigation points in the water contents of rockwool cube is IP 50%.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.179-185
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• 2013

This study was carried out to find a reasonable irrigation method of a nutrient solution for the phenolic foam slab (foam LC) used in a trial experiment to substitute the rockwool slab in the production of paprika (Capsicum annuum 'Veyron'). 100, 90, and 80 mL of a nutrient solution was supplied per plant each time when the accumulated radiation reached to 100, $90J{\cdot}cm^{-2}$, and they were named as the 100-100, 90-90, and 90-80 treatment, respectively. The drain percentage per plant of the 100-100 treatment was high by 33.8% in rockwool and 36.7% in foam LC (Lettuce Cube) and that of 90-80 treatment was low by 30.4% and 33.7%. The water content and EC of the rockwool slab were maintained in the range of 63.6-68.9% and $4.4-5.1mS{\cdot}cm^{-1}$, while those of the foam LC slab were in the range of 52.9-58.8% and $5.5-6.5mS{\cdot}cm^{-1}$. The plant height and leaf size of the 100-100 and 90-90 treatments increased in a similar manner, while those of the 90-80 treatment decreased and those of the rockwool were greater than those of the foam LC. The fruit size and weight of the 100-100 and 90-90 treatments were similarly bigger and heavier than those of the 90-80 treatment. The number of fruits harvested per plant was the greatest in the 90-80 treatment with 8 and 8.3 fruits in the rockwool and foam LC. The number of marketable fruits in the rockwool and foam LC was the greatest with 18.1 and 18.2, respectively, in the 90-90 treatment, while that in the 90-80 treatment was 17.2 and 16.8, respectively. The number of unmarketable fruits of the 90-80 treatment was the greatest (1.7-1.8 fruits per plant) in both the rockwool and foam LC, and most of them were small sized or blossom end rot fruits. The yield of the 90-90 treatment was the greatest among the irrigation.

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.60-66
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• 2022

This study was conducted to investigate growth characteristics of paprika seedlings according to various qualities of LED light (red : blue = 10 : 0, red : blue = 8 : 2, red : blue = 2 : 8, white). Plant height and stem were significantly longer or thicker as red light ratio increased. Leaf area of paprika seedlings with red light was larger or no significant differences in a mixed light of red and blue. Dry weight of seedling was in the same with the result of leaf area. Seedlings with White light was significantly less than others in all characteristics. As red light ratio was increased, relative growth rate increased. As blue light ratio was increased, the net assimilation amount increased. Considering plant height, leaf area and production ability of dry matter per unit leaf area, the using mixed red and blue lights was suitable, especially at a mixed red : blue = 8 : 2.

• Journal of Bio-Environment Control
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• v.6 no.1
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• pp.27-33
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• 1997

This experiment was carried out to investigate the effects of limited nutrient supply during 21 days before and after pollination stage on the growth, fruit quality and nutrient uptake of muskmelon in rockwool culture. Muskmelon, cv. Earl's Favorite seeds sowed on rockwool cube and transplanted on rockwool slab($90\times15\times7.5cm$) when 2 to 3 true leaf appeared on Sep. 6, 1991. Three kinds of nutrient composition recommended by Shizuoka university, combinated with the composition of Otsuka house A and composition Shizuoka III. One half of calcium nitrate(Ca(NO$_3$)$_2$.4$H_2O$) for limiting nitrogen supply during 21 days was treated and then fertigated the nutrient composition recommended by Shizuoka university up to harvest time. Trickling nozzles(Netafim Co. Israel) were used for fertigation of nutrient solution and noncirculating system was employed. Temperature was maintained $18^{\circ}C$ in night but 23 to $25^{\circ}C$ for 10 days after pollination for softening the fruit. The drainage ratio of nutrient solution was adjusted 20 to 30 percent. Fertigated and drained amount, and the pH and EC of nutrient solution were recorded. The concentrations of mineral elements including N, P, K, Ca, and Mg were analyzed and compared among treatments. In both autumn and winter cultivation, the limitation of nutrient supply by adjustment of nutrient composition(NO$_3$-N : 8meㆍ$\ell^{-1}$) caused the nutrient deficiency in muskmelon plant due to the limited nutrient supply. After pollination nutrient limitation by the lowering the nitrate retarded the over thickening of upper leaves of muskmelon but plant height and fresh weight of fruit were higher in the plot of nonlimited nutrient supply. The phenomena were attributed to the differences of the amount of nutrient uptake due to the limited time of nutrient solution, duration of nutrient supply and concentration of nutrient solution. These results suggested that increasing nutrient supply in the pollination stage was favorable for better appearance of fruit and improving fruit quality. Further trials would be required for the incre-ment of sugar degree of muskmelon grown in rockwool.

• Research in Plant Disease
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• v.11 no.2
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• pp.179-184
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• 2005

A previous study reported that the stem and root rot of paprika (Capsicum annum L. var, grossum) caused by Nectria haematococca became a threat to safe cultivation of the plant in the country. However, no strategies for control the disease have been suggested. In this study, fungicides registered for pepper were screened to evaluate their control effects on the disease. Among fungicides tested, prochloraz manganase complex com pletely suppressed mycelial growth of the pathogen at 10 ppm a.i. tebuconazole, benomyl, and carbendazim $\cdot$kasugamycin also effectively inhibited mycelial growth of the fungus. However, kresoxim-methyl and triflox ystrobin did not suppress mycelial growth but significantly suppressed conidial germination of the fungus. Azoxystrobin, benomyl, prochloraz, tebuconazol, and carbendazim$\cdot$ kasugamycin were also effective to retard conidial germination. In vivo tests, tebuconazole strongly inhibited the plant growth even at 16,000x (15.6 ppm a.i.), while others did not induce chemical injury at 4,000x or 8,000x when drenched into a rockwool cube. In a greenhouse test, prochloraz manganase complex at 125 ppm a.i. (4,000x) showed highest control value by $89.9\%$. Other fungicides thiophanate-methylthiram, axozystrobin, trifloxystrobin, and benomyl presented $60-80\%$ control value in the hydroponic cultivation system. However, application time and interval remained to be investigated for identify maximum residue limit.