• Horticultural Science & Technology
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• v.33 no.2
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• pp.166-176
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• 2015

Research was initiated to investigate root growth characteristics of major cool-season grasses (CSG) and to collect basic information useful for sports turf design, construction and maintenance. Several turfgrasses were evaluated in the USGA (United States Golf Association) soil system. Turfgrass entries were comprised 3 blends and 3 mixtures of Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), and tall fescue (TF, Festuca arundinacea Schreb.). Significant differences were found in root growth, rooting potential and rooting development. These characteristics increased with time after seeding, but varied with establishment stages. In early stage, root length was highest with PR, intermediate with TF and lowest with KB. Evaluation in a middle stage indicated that root growth was similar to early-stage evaluation, but decreased by 13 to 31% compared with early-stage values. Root growth of late stage increased by 34 to 85% over middle-stage root growth. Overall, thhere was not much difference in root length among treatments, with all except Mixture I reaching 22cm in root length. Rooting potential ranking was variable with establishment stage, being PR > KB > TF in early stage, PR > TF > KB in middle stage and TF > PR > KB in late stage. At the end of the study, TF was rated best for rooting development, followed by PR and finally KB. Our results showed that TF was the best species in regard to overall rooting characteristics. TF exhibited excellent rooting development with time after establishment. Bunch-type PR showed fast root growth in the early stage, but rooting quality characteristics decreased with time, especially for rooting development. By contrast, rhizomatous-type KB was poor in early-stage root growth, but rooting characteristics improved with time after establishment. These variations in rooting characteristics among CSGs were considered to arise from differences in establishment vigor, growth habit and genetic characteristics. Information on root growth, rooting potential and rooting development by establishment stages will be useful for sports turf design, construction and maintenance.

• Korean Journal of Weed Science
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• v.6 no.2
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• pp.110-123
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• 1986

To know the ecological pattern of bulrush (Scirpus juncoides Roxb.) seeds and overwintreed stumps in germination and sprouting responses as affected by different temperature (7 trt.), light intensity (5 trt.), shading intensity (S trt.), light quality (specturm spectrum; 6 trt.), soil acidity (7 trt.), stump sizea (weight base; 5 trt.), and molding depth (6trt.), respectively, this serial studies were conducted by use of growth chamber, incubator, Wagner pot and petri-dish. Most efficient treatment was obtained from 25-$35^{\circ}C$ temperature, higher light intensity in 2-11 klux range, 95% shading intensity, clear and yellow film for seeds/clear and blue film for stumps, soil pH 5.53, 3-4g stump weight, 0-5% wxygen concentration, 1 ㎝ flooding depth for seeds, and 1-1.5cm molding depth for seeds/0.5-1.0 cm molding depth for stumps, respectively, among others.

• Korean Journal of Agricultural Science
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• v.19 no.1
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• pp.16-27
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• 1992

To determine a potential of new sludge fertilizer for horticultural crops, comparative studies between commercial fertilizers (Jandibiryo and Wonyebokbi) and sludge fertilizer (Sludgebiryo) were made through examining the growth responses on zoysiagrass (Zoysia japponica Steud.) and several horticultural plants. 1. The pH of new sludge fertilizer remained near 6.5 regardless the particle size. The solubility of elements was highest in phosphorus, followed by nitrogen and potassium in the order. Especially, desorption of potassium was continued up to 48 hrs after solubilization. 2. There was an increase in shoot number per plant, length of stolon and rhizome, and root weight as well as clipping yield of zoysiagrass in the treatment of large size Sludgebiryo compared to small one and Jandibiryo. 3. Regardless the size of fertilizers, Sludgebiryo increased flower numbers in salvia (Salvia officinalis L. 'Hatzazz') compared to Wonyebokbi, although the difference was not great, However, leaf area and fresh weight of plant were more increased in Wonyebokbi application. 4. Flower diameter of marigold (Tagetes erecta L. 'Inca') was slightly increased in Sludgebiryo application, but the average number of lateral shoots and fresh weight per plant were significantly increased in the treatment of Wonyebokbi application. 5. Sludgebiryo effectively increased the length of both main and lateral shoots, number of flowers and weight of shoot in vinca (Vinca rosea L. 'Little Linde'), but root growth of plant was higher in Wonyebokbi application. 6, No differences between Wonyebokbi and Sludgebiryo were found in promoting the growth of leaves of perilla (Perilla frutescens Hara 'Yubsil' ), but chlorophyll content and seed weight were slightly higher in the application of Wonyebokbi compared to Sludgebiryo. In conclusion, the effectiveness of Sludgebiryo for horticultural plants was almost equal to commercial fertilizers such as Jandibiryo or Wonyebokbi. Expecially, Sludgebiryo appeared to effective on the growth of zoysiagrass, and the increase of flower size and numbers in flower crops. Results indicate that new-made Sludgebiryo can be recommended for turfgrass culture, and the flower crops in which quality depends on flower number and flower size.

• Korean Journal of Weed Science
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• v.16 no.3
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• pp.187-193
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• 1996

To supply seeds with a good quality as plant materials for herbicide screening and to know whether the germination characteristics could be associated with a differential response to herbicides, germination characteristics and differential responses to herbicides were investigated with 3 species of a genus Setaria ; Yellow foxtail(Setaria glauca P. Beauv, SETGL), Giant foxtail(Setaria faberi Hetrm, SETFA), and Green foxtail(Setaria viridis P. Beauv, SETVI). Degree of dormancy was high in the order of SETGL, SETVI and SETFA. The dormancy of SETGL seed was relatively well removed by room temperature and drying storage, but SETFA and SETVI by low temperature and wetting storage(stratification). For breaking dormancy of SETGL, SETVI and SETFA, it was necessary for being kept under the above storage conditions for at least 2, 4 and 4-5 months, respectively. When the dormancy-breaked seeds were transfered to low temperature($4^{\circ}C$) and drying condition, SETGL showed germination rate of 96% even after 2 month storage. However, SETVI and SETFA showed a decreased germination of 54% and 69%, respectively, with a decreased velocity of germination, indicating that secondary dormancy might be induced. On the other hand, a significant change in germination rate was not observed as the seeds were transfered to room temperature($25^{\circ}C$) and drying condition. The germinability of SETGL seed began to decline from 6th year after storage in room temperature and drying condition. All of 3 species showed relatively high germination rate at alternating temperature of $30^{\circ}C$/$20^{\circ}C$(14hr/10hr) and their germination were not increased by light. All of 3 species exhibited similar responses to cycloxydim, sethoxydim and primisulfuron in greenhouse experiment. In contrast, SETVI and SETFA were relatively susceptible to fenoxapropethyl, SETFA to fluazifop-butyl, SETGL and SETFA to clorimuron-ethyl, and SETGL to EK-2612. The difference in herbicidal response among 3 species was the highest in the treatment of EK-2612. These results suggest that there is no a consistent tendency in responses of 3 species to herbicides which have the same target site. And the relationship between germination characteristics and differential responses to herbicides was not found.