• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.102-109
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• 1998

This study was conducted to find out the growth characteristic of mixed-seeding in the grasses for slope revegetation measures. Seeding treatment with six combination types of five grasses used for this experiment such as orchardgrass(Dactylis glomerata 'Potomac'), perennial ryegrass(Lolium perenne 'Manhattan'), tall fescue(Festuca arundinacea 'Jaguar'), kentucky bluegrass(Poa pratensis 'Majestic') and weeping lovegrass(Eragrostis curvula). The growth of orchardgrass, perennial ryegrass and tall fescue were good on mixed-seeding condition in case of number of individuals, heights and coverages at this experiment. These plants will useful for revegetation measures mixed-seeding, but weeping love grass and kentucky bluegrass did not show a desirable growth in mixed-seeding condition, and these plant prefered mixed seeding to single seeding. Regeneration percents of orchardgrass, perennial ryegrass and tall fescue were higher than that of weeping love grass and kentucky bluegrass, and coverage kept on good condition through one year after seeding, therefore, these plants will effective for initial stage revegetation measures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.1
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• pp.70-79
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• 1977

Perennial weeds which were grown in transplanted paddy field formed their tubers under shortday condition. Under short day treatment, the induction periods for tuber formation were different depending upon the weed species. 80% cut tubers of the weeds did not loose their developing ability perfectly. Emergence also affected by soil conditions and depths covered.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.1
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• pp.20-23
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• 1976

Distribution of underground organs of perennial weeds in soil and ecological control measure were evaluated. Tubers of Cypers serotinus and Sagittaria pygmaea were mostly presented in a shallow depth of 0 to 5cm, however, Potamogeton distinctus's bulbs and Eleocharis kuroguwai's tubers were distributed in the soil at 10 to 20cm. A 20cm autumn plowing was, to some extent, effective to reduce Potamogeton distinctus. The herbicide, avirosan at 3kg/10a alone, was extremely effective in controlling Potamogeton distinctus.

• Korean Journal of Bronchoesophagology
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• v.4 no.1
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• pp.85-90
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• 1998

The role of the ECP(Eosinophilic cationic protein) is still unknown in the allergic rhinitis. In bronchial asthma, ECP can induce the exposure of the neuropeptidergic nerve to environments destroying the bronchial mucosa, aggravating the bronchial hypersensitivity and delay the mucociliary clearance. In the clinical aspect, we can (md that patients with perennial allergic rhinitis sometimes have sinusitis. The purpose of this article is to evaluate whether mucosal damage by ECP can play a role to develop the sinusitis by delaying the mucociliary clearance, and relationship between long symptom duration of allergic rhinitis and mucociliary clearance. In 32 perennial allergic rhinitis patients, we elucidated there is correlation among ECP presence, mucociliary clearance, sinusitis, and symptom durations. The obtained results were as follows : 1. ECP appeared in all mucosa of each specimen. 2. Mean mucociliary clearance time is 6 mins. 12 sec. in allergic patients with sinusitis, 6 mins. 36 sec in allergic patients without sinusitis. 3. n out of 32 cases have mucosal destruction. 4. Symptom duration is not correlated with the development of sinusitis. This study suggests that ECP may destroy the mucosa in allergic rhinitis and the mucociliary clearance of allergic rhinitis is not related to sinusitis and symptom dotation. Therefore development of sinusitis in allergic rhinitis seems not to be caused by delaying of mucociliary clearance due to mucosal destruction, but by some other factors.

• ALGAE
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• v.37 no.1
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• pp.63-74
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• 2022

Perennial stipitate kelps are globally distributed and individual species can inhabit broad latitudinal ranges, expressing notably longevous persistence. Despite the foundational role kelps provide to their communities, little is known about the variability in persistence of the stipitate kelps at local spatial scales. We studied the population persistence of Eisenia arborea, a heat- and wave force-tolerant perennial stipitate kelp with a distributional range extending from British Columbia to south of the range limit of all other northeast Pacific kelps, in Baja California Sur, Mexico. Persistence characteristics for E. arborea among sites were compared and used to test the hypothesis that stand persistence varied at local spatial scales around Isla Natividad, a Pacific island off the Baja California peninsula with documented spatiotemporal environmental heterogeneity. Collected individuals around the island were "aged" using the previously validated age estimation technique of counting annual cortical dark rings. After detecting no significant differences among sites in the covariation between estimated ages for collected individuals and stipe length, we utilized in-situ population-level stipe length measurements to more rapidly predict age structures within six stands around the island. Predicted age structures, and associated stand densities, revealed persistence characteristics and density varied at local scales and a strong positive relationship existed between stand density and stand mean and maximum ages. We speculate that stands responded differently to deterministic influences (e.g., the 2014-2016 marine heatwave and / or competition with Macrocystis) resulting in heterogenous local persistence of this foundation species.

• Horticultural Science & Technology
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• v.29 no.4
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• pp.306-310
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• 2011

This study examined the changes in the distribution of nitrogenous compounds in various parts of 3- and 4-year-old persimmon (Diospyros kaki cv. Fuyu) with fruits (fruited) and without fruits (defruited). The effect of the changes was then related to the storage and their reutilization for new growth in the following year. From June 15 to November 1, the partitioning of amino acids among perennial parts of fruited trees was inconsistent, whereas that of defruited trees was characterized by a significant increase. Compared with the fruited trees, amino acids accumulated in the perennial parts of defruited trees were 1.66 g and 3.48 g more in 3- and 4-year-old trees, respectively. Of the total proteins increased during this period, the proportions distributed to the perennial parts of the tree were less than 50% for fruited trees, but they were more than 90% for defruited trees. Roots were the strongest sink for proteins; percent proteins in the roots amounted to 94 in defruited 3-year-old trees and 76 in 4-year-old trees. Compared with the proteins accumulated in perennial parts of fruited trees, those of defruited trees were 1.64 g more in 3-year-old and 2.58 g more in 4-year-old trees. During this period, the nitrogenous compounds decreased by 0.50-0.56 g in the leaves of fruited trees, while they increased by 0.66-0.78 g in their fruits. During the new growth from April 10 to June 10 of the following year, amino acids decreased both in the fruited and defruited trees. Proteins, especially in the root, decreased in the trees that had been previously defruited. More amino acids and proteins were found in the newly grown parts of the defruited trees. Compared with the fruited trees, the defruited trees accumulated nitrogenous compounds more in roots than in the other parts of the perennial parts. The reserve nitrogenous compounds contributed to the new shoot growth and fruit set in the following year.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.3
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• pp.165-170
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• 2009

A system for the production of transgenic plants has been developed for perennial ryegrass (Lolium perenne L.) via Agrobacterium-mediated transformation. Included in this study were two factors which may affect the gene transfer efficiency: concentrations of acetosyringone (AS, 0 to 300 ${\mu}M$), and co-culture period (1 to 7 days). Both factors were very important to achieve high efficiency gene transformation in the perennial ryegrass. The highest transformation efficiency was obtained when embryogenic calli were inoculated with Agrobacterium in the presence of 100 ${\mu}M$ AS with the culture medium for 5 days. Phosphinothricin resistant calli were developed with into complete plants. GUS histochemical assay, polymerase chain reaction (PCR) and Northern blot analysis of transgenic plants demonstrated that transgenes were integrated into the genome of perennial ryegrass. Using this protocol, it was possible to obtain transformants efficiently for further study.

• Asian Journal of Turfgrass Science
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• v.26 no.2
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• pp.83-88
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• 2012

When perennial ryegrass was overseeded in bermudagrass fairway, shoot density of perennial ryegrass was gradually increased to $88,000/m^2$ at the end of May, however dramatically decreased to 0 in September over the rainy season. On the other hand, that of bermudagrass increased from $2,000/m^2$ in March to $20,000/m^2$ in early June, and then decreased to $4,000/m^2$ at the end of July, after the rainy season, rapidly increased to $50,000/m^2$ in early September. Overseeding bermudagrass fairway with perennial ryegrass was maintained a good quality from mid-April to mid-June and decreased the quality over the rainy season from late June to July, and then turf quality was decrease to the worst level at the end of July. After the rainy season fairway quality was improved gradually and was the highest-level during September and early October. Trifloxysulfuron-sodium was treated to minimize the deterioration in turf quality due to early bermudgrass transition time in spring. Consequently, transition was started in mid-May and shoot density of bermudagrass treated by trifloxysulfuron-sodium was $70,000/m^2$ in mid-June. Even in the rainy season it was sustained as $30,000/m^2$, approximately three times higher than that of untreated overseeding fairway.

• Asian Journal of Turfgrass Science
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• v.18 no.1
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• pp.1-13
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• 2004

The growth characteristics of cool season turfgrass in the seaside landfill golf courses with the single-use of kentucky bluegrass and mixed-use with kentucky bluegrass and perennial ryegrass in the coast line are as follows. Water infiltration rate was higher in the kentucky bluegrass single-use groups recorded as 95.6∼125.9cm/hr than in the roups mixed with kentucky bluegrass and perennial ryegrass recorded as 180.3∼386.2cm/hr. The surface soil hardness and the soil penetration were ranged from 16.6 to 18.0mm and from 6.0 to 7.3kg/cm$^2$, respectively. The cultivar that showed the most excellent visual quality and visual color in the kentucky bluegrass single-use groups was Midnight(KB2), whose density around the root was relatively excellent, as well. North Star(KB3) known as highly resistant to salt was the secondarily excellent cultivar. Brilliant(KB1) had visual quality of about third grade, however, it seemed profitable to develop turfgrass ground by virtue of its high density. As of April 26, 2003, when 2 weeks had passed after seeding, the visual quality was better in the groups mixed with kentucky bluegrass and perennial rye grass than in the kentucky bluegrass single-use groups. The most excellent visual color was found in Midnight(KB2)+Brightstar SLT(PR2) among the groups mixed with kentucky bluegrass and perennial ryegrass. On August 4, 2003, a disease was found from one experimental group in Blackstone(KB4) and expanded into more than 50cm of diameter.

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.242-248
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• 2023

This study was conducted to evaluate the effects of trinexapac-ethyl (TE) and prohexadione-calcium (PC) on the growth and turf quality of perennial ryegrass (Lolium perenne L.). Treatments were designed as follows; control (non-treatment), TE (TE 0.01 a.i. g·m^-2·100mL^-1), and PC (PC 0.01 a.i. g·m^-2·100mL^-1). Compared with control, turf color index and chlorophyll content of TE and PC treatments were not significantly different. As applied plant growth regulators (PGRs), shoot length in the TE and PC was decreased by 8.9-12.4% and 6.7-13.6%, respectively, and clipping yield by 44.4-45.8% and 40.6-40.9%. When evaluated with the growth of shoot length after applying PGRs, residual days of TE and PC were 43.6 and 37.9 days after treatment of PGRs (DAT) in the 1st experiment (July 29-August 26), respectively, and 38.3 and 39.5 DATs in the 2nd experiment (September 30-October 28). These results indicated that an application of TE or PC decreased shoot length and clipping yield in the perennial ryegrass, and their residual time was about 40±3 DATs. Perennial ryegrass applied with PGRs like TE and PC was not significant seasonal difference, and might be not phytotoxic.