• Journal of Environmental Science International
• /
• v.27 no.10
• /
• pp.821-829
• /
• 2018

This study was conducted to examine the influence of Light-Emitting Diode (LED) light quality in urban agricultural plant factories on the growth and development of Seolhyang strawberry daughter plants in order to improve the efficiency of daughter plant growth and urban agriculture. LED light quality by demonstrated that above-ground growth and development were greatest for daughter plant 2. Daughter plant 1 showed the next highest growth and development, followed by daughter plant 3. Among the different qualities of LED light, the stem was thickest and growth rate of leaves was highest for R + B III (LED quality: red 660 nm + blue 450 nm/photosynthetic photon flux density (PPFD): $241-243{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and lowest for R (red $660nm/115-117{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). Plant height, leaf width, petiole length, and the leaf growth rate were highest for W (white fluorescent lamp/$241-243{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and lowest for R + B I (red 660nm+blue 450nm/$80-82{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). For above-ground growth and development, as the plants surpassed the seedling age, mixed light (red + blue), rather than monochromatic light (red or blue), and higher PPFD values tended to increase development. Regarding the quality of the LED light, daughter plant 2 showed the highest chlorophyll content, followed by daughter plant 1, and daughter plant 3 showed the least chlorophyll content. When the wavelength was monochromatic, chlorophyll content increased, compared to that when PPFD values were increased. Mixed light vitality was highest in daughter plant 2, followed by 1, and 3, showed increased photosynthesis when PPFD values were high with mixed light, in contrast to the results observed for chlorophyll content.

• Horticultural Science & Technology
• /
• v.29 no.3
• /
• pp.273-277
• /
• 2011

Fusarium oxysporum f. sp. fragariae (Fof), the causal agent of crown and root rot in strawberry, is the most serious soilborne disease of nursery plants in Korea. The possibility of infection by Fof through runner propagation from infected mother plants of strawberry cv. 'Kumhyang' was assessed in stolons and daughter plants hanging from raised beds. The number of daughter plants from an infected mother plant in plastic house and photosynthetic photon flux (PPF) system, 280 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ was 2.7 and 3.8 plants after 58 days, respectively. However, healthy mother plants produced 6.5 and 8.4 daughter plants, respectively. The pathogen was detected in the uppermost portion of the stolon after 58 days, but was not detected further down the stolon. After 90 days, it was detected in all portions of the stolon between mother and $1^{st}$ daughter plant and in 60% of all $1^{st}$ daughter plants. The pathogen was not detected in the corresponding portions of the non-infected controls. These results show that infected mother plants can transmit Fof to their daughter plants without passing through the soil and $1^{st}$ daughter was used as mother plant in PPF system for propagating healthy plants.

• Korean Journal of Agricultural Science
• /
• v.47 no.3
• /
• pp.625-632
• /
• 2020

This test was conducted to determine the appropriate conditions of temperature, storage period, and soil moisture content when using cold storage of potted mother plants of as a means of sufficient dormant breaking and safe overwintering of the strawberry (Fragaria × ananassa Duch. cv. Sulhyang) mother plants. In the treatment by temperature for the dormant breaking of strawberry mother plants, the survival rate of natural overwintering was 91%, whereas the survival rate was 100% at 0, - 2, and - 5℃. As the storage temperature was decreased, the plant height of the mother plants became shorter which tended to decrease after planting. Survival of the mother plants was possible at - 5℃, but after planting, the growth and number of daughter plants decreased significantly. The number of daughter plants was highest at 22.8 per plant at - 2℃ storage. The strawberry mother plants could be stored for up to 8 months in cold storage. However, when the mother plants were stored for a long period, the number of daughter plants was small. When they were stored for 4 months, the growth of the mother plants was vigorous, and the number of runners and daughter plants was high. When the water content of the soil was less than 10 percent (%, w/w) in the cold storage of the pot, the survival rate was 85 percent, which was high due to the dryness. The survival rate was 100 percent at 30 and above, and the growth of the mother plants after planting and the number of daughter plants were high at 30 to 50.

• Horticultural Science & Technology
• /
• v.34 no.2
• /
• pp.242-248
• /
• 2016

This research was conducted to determine the effects of four different substrates, expanded rice hulls (ERH), commercial substrates for strawberries (CSS), clay sand (CS), and loamy sand (LS), on the inhibition of anthracnose crown rot (ACR) in strawberry. Mother plants of 'Seolhyang' strawberry were transplanted into an elevated bed in March, 2013 and March, 2014 and the runners connecting mother plants and daughter plants were cut in early August of both years. After separation, growth characteristics of the daughter plants were measured and then each daughter plant was inoculated with conidial suspensions of Colletotrichum fructicola, one of several species of Colletotrichum that causes ACR in strawberries. The incidence of ACR as influenced by the different substrates was investigated in both years. The daughter plants grown on CSS had the highest values for shoot height, leaf area, and fresh weight. Those grown on ERH and LS substrates also displayed good above-ground growth characteristics except for fresh weight, but the daughter plants grown on CS had the poorest above-ground growth characteristics. The ERH and CS treatments resulted in the highest number of primary roots and the greatest root weight. The CSS-grown daughter plants had the highest ACR disease index, followed by the CS and LS treatments, but there were no significant differences among the three substrates. However, the ERH-grown daughter plants had a markedly lower ACR disease index on October 11, 2013 and October 7, 2014. The CSS-grown daughter plants had high nitrogen and potassium contents and low calcium content, whereas the ERH-grown daughter plants had low nitrogen levels and high silicon levels. The results of this study provide basic information on the ability of the different substrates tested to provide disease suppression of ACR in the propagation of strawberry transplants.

• Journal of Bio-Environment Control
• /
• v.27 no.4
• /
• pp.407-414
• /
• 2018

This study was aimed to evaluate the effect of application method and concentration of gibberellin $A_3$ ($GA_3$) on the growth, runner production, and seedling quality of strawberry plants (Fragaria ${\times}$ ananassa Duch. cv. Maehyang) during nursery period. The mother plants of strawberry were transplanted in pot ($64{\times}27{\times}18cm$) filled with commercial growing medium on March 20, 2018. $GA_3$ concentration was applied as 0, 50, 100 or $200mg{\cdot}L^{-1}$ with spray or drench to 45 mL per plant at 4 weeks after transplanting, respectively. Nutrient solution was supplied with the EC $1.5dS{\cdot}m^{-1}$ after the transplanting and supplied 350 mL per pot twice a day (15 min per one time) after rooting. The growth characteristics of mother plants of strawberry were measured at 7 weeks after treatment, and growth characteristics of daughter plants of strawberry were measured at 10 weeks after treatment. Runner length and diameter of mother plant was the longest or thickest in the spray with $200mg{\cdot}L^{-1}$ than the other treatments, respectively. Soil-plant analysis development (SPAD) value of mother plant was the lowest in spray with $200mg{\cdot}L^{-1}$. However, leaf length, leaf width, and crown diameter showed no significant differences in all treatment among application method and concentration of $GA_3$. As the concentration of $GA_3$ increased, physiological disorder like stretchiness of crown occurred more. The physiological disorder was the most occurred in spray treatment with $200mg{\cdot}L^{-1}$, but drench treatment occurred less than spray treatment. The number of runners and daughter plants increased with increasing concentration of $GA_3$ regardless of application methods. In the growth characteristics of the daughter plants, leaf length and leaf width of first daughter plant, plant height, crown diameter, leaf area and SPAD value of second daughter plant, and plant height of third daughter plant were the significantly greatest in drench with $100mg{\cdot}L^{-1}$ treatment. This results indicate that growth and runner production of mother plants and growth of daughter plants of strawberry were the best achieved by drench application in the $100mg{\cdot}L^{-1}$ $GA_3$.

• Korean Journal of Agricultural Science
• /
• v.49 no.4
• /
• pp.697-706
• /
• 2022

The effect of varied light intensities on the growth of daughter plants during propagation and after transplant to raised beds were examined in 'Sulhyang' strawberry. To this end, four treatments in controlling solar radiation inside a plastic house were made: 55% retractable shading and 35, 55, and 75% fixed shading. The plastic house was shaded only from 11:00 to 16:00 in June and 10:00 to 16:00 in July to September for the treatment of 55% retractable shading. The mean solar radiation inside the plastic house in the retractable 55% shading treatment was 317 W·m^-2 and those in the 35, 55, and 75% fixed shading treatments were 183, 165, and 116 W·m^-2, respectively, at 10 o'clock in the morning. The 55% and 75% fixed shading resulted in taller daughter plants with wider leaf areas than 55% retractable shading. The retractable shading also showed higher leaf numbers, crown diameters, root weights, and fresh weights compared to fixed shading treatments. Regarding the inorganic element contents, daughter plants grown under 75% fixed shading had 1.35% total nitrogen content followed by 1.19% in 35% fixed shading, 1.14% in 55% fixed shading, 1.14% in open culture, and 1.10% in 55% fixed shading. After 54 days following the transplant of daughter plants to a raised bed, the fresh weight of the aboveground part was the heaviest in the 55% retractable shading and non-shading treatments. The 75% fixed shading treatment had the lowest fresh weight of the aboveground plant parts. The results of this study could be used for the production of high-quality daughter strawberry plants.

• Journal of Bio-Environment Control
• /
• v.30 no.4
• /
• pp.257-262
• /
• 2021

The pinning method is the traditional method to produce strawberry transplants. But, cultivating the pinning transplant is a labor-intensive operation and needs a long labor period. The cutting method has been considered as an effective alternative to the pinning method, due to the relatively short labor period and works time. This study was conducted to investigate the labor period, work time, and growth between pinning and cutting methods for strawberry transplants. The 'Maehyang' strawberry was cultivated at each pinning and cutting strawberry greenhouses. The time for special works on pinning method (pinning work, elimination of mother plant, and division of daughter plant), and cutting method (cutting collection, pretreatment before storage, and cutting work) were measured. The pinning method needed 6 tasks (planting of mother plant, maintaining of mother plant, pinning work, maintaining of daughter plant, elimination of mother plant, and division of daughter plant) for 158 days, and cutting method needed 4 tasks (collection and storage of cutting, cutting work, misting, and maintaining of transplants) for 113 days to cultivate transplants for fruit. And pinning method needed more work time than the cutting method. There was no significant difference between the growth of pinning and cutting transplants. These results showed that the cutting method saved more labor period, work time than pinning during the nursery period without losing transplant quality.

• Korean Journal of Agricultural Science
• /
• v.37 no.2
• /
• pp.191-197
• /
• 2010

The objective of this research was to determine the influence of the physical and chemical properties of root substrates used during the production of 'Maehyang' strawberry propaguleson the growth of the mother plants and the rate of daughter plant formation. Plants were cultured in plastic bags containing six different formulations of root substrates composed of: a) 50% coir dust and 50% perlite (5:5 by volume, A), b) 60% coir dust and 40% perlite (6:4, B), c) 70% coir dust and 30% perlite (7:3, C), d) 70% coir dust and 30% coconut chip (7:3 D), e) 60% coir dust and 40% coconut chip (60:40, E), or f) 50% sphagnum peat and 50% vermiculite (50:50, F). All media formulations contained a moderate level of base fertilizers. Physical and chemical properties of each formulation were determined before plant establishment and after 120 days of stock plant culture and runner production. Total porosity (TP) and container capacity (CC) of all substrate formulations were higher than 85% and 55%, respectively, allowing a suitable range of air and water holding characteristics. Formulation F provided the highest TP and CC values among the all substrate modifications evaluated. Substrate formulations A, B, C and F had higher electrical conductivity (EC) and $NO_3{^-}$-N concentrations than formulations D and E, when determined before and after plant culture. Formulations A, B, C, and F, having higher EC readings, also performed better as root substrates thanthe formulations D and E in increasing fresh and dry weights of the runners as well as the production of daughter plants per plant. The 'Maehyang' strawberry plants grown in the formulation F had the highest tissue N content, followed by those grown in substrate B, A, C, or D for 120 days after transplanting. Formulation F also facilitated accumulation of higher tissue phosphorus (P) and copper (Cu) contents compared to other treatments. Results of this experiment suggest that the chemical properties, rather than physical properties, of root substrates had a major influence on the growth of mother plants and the occurrence of healthy daughter plants during the bag-culture phase of propagation.

• Journal of Bio-Environment Control
• /
• v.27 no.2
• /
• pp.185-190
• /
• 2018

This study was conducted to investigate the optimum electrical conductivity (EC) levels of nutrient solution for growth of mother plants and increasing occurrence of daughter plants of strawberry ($Fragaria{\times}ananassa$ Duch. cv. Maehyang) using hydroponics. The mother plants of strawberry were transplanted in cultivation pot ($61{\times}27{\times}18cm$) filled with coir medium on March 22, 2017. Nutrient solution was supplied by the drip tape at $0.6dS{\cdot}m^{-1}$ of EC levels for rooting during 11 days. After rooting, the mother plants of strawberry was treated at the EC levels of 0.6, 1.2 or $1.8dS{\cdot}m^{-1}$, respectively. Growth characteristics, such as mother plants and daughter plants of strawberry were measured at 100 days after transplanting. The plant height of mother plant was significantly higher at $0.6dS{\cdot}m^{-1}$ treatment, and the crown diameter of mother plant was significantly greater at $1.8dS{\cdot}m^{-1}$ treatment. The fresh and dry weights of shoot were higher at both 0.6 and, $1.2dS{\cdot}m^{-1}$ treatments. The number of runners was not significantly different in all treatments. The fresh and dry weights of runner were heavier at $0.6dS{\cdot}m^{-1}$ than other treatments. The number of daughter plants was the highest, 16.7 at the $1.2dS{\cdot}m^{-1}$ treatment. However, the fresh and dry weights of third daughter plant were the heaviest at $0.6dS{\cdot}m^{-1}$ treatment. Although the daughter plants were a large of production at $1.2dS{\cdot}m^{-1}$ treatment, the low EC levels of strawberry were positive in terms of seedling quality during nursery. These results indicated that growth of mother plant and occurrence of daughter plants were greater at the EC $0.6dS{\cdot}m^{-1}$ nutrient solution for hydroponic cultivation of 'Maehyang' strawberry during nursery period.

• Horticultural Science & Technology
• /
• v.28 no.6
• /
• pp.964-972
• /
• 2010

Objective of this research was to determine the influence of physico.chemical properties of root substrates on growth of daughter plants that were developed through plastic bag cultivation of mother plants in 'Seolhyang' strawberry propagation. Six different formulations of root substrates for daughter plant cultivation were peatmoss + vermiculite (5:5, A), peatmoss + perlite (7:3, B), coir dust + perlite (7:3, C), coir dust + peatmoss + perlite (3.5:3.5:3.0, D), rice-hull + coir dust + perlite (2:7:1, E), and rice hull + coir dust (3:7, F). The 10 cm plastic pots filled with formulated substrates were located near the plastic bag where mother plants were growing. Then the runners and daughter plants originated from mother plants were fixed on each root substrate filled into 10 cm plastic pot and daughter plants were grown in the plastic pots. The container capacity and air space showed big differences among substrates tested. The substrates E and F had the less container capacity and the higher air space than other substrates tested. This indicates that the two substrates would have difficulties in water managements during the raising of daughter plants. The substrates of A, B, and D which contained peatmoss in formulation had higher nitrogen concentrations than those containing coir dust or rice hull. The substrates of E and F which contained rice hull had lower nitrogen, phosphorus and potassium concentrations than those that contained coir. The crown diameters of daughter plants grown in substrate A were around 13 mm which is thicker than those grown in other substrates. The fresh weights of daughter plants grown in A substrate were the heaviest followed by C, F, D, E, and B. The dry weight of daughter plants showed similar tendency to those of fresh weight. The daughter plants which had heavy fresh and dry weights and thick crown diameter are considered good seedlings. Based on this justification, the substrates of A, C and F are acceptable for daughter plant growth of 'Seolhyang' strawberry.