• Korean Journal of Plant Taxonomy
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• v.50 no.4
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• pp.413-418
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• 2020

A new variety, Lecanorchis japonica var. insularis (Orchidaceae: Vanilloideae), a mycoheterotrophic orchid from Jejudo Island, Korea, is described and illustrated. It usually grows with L. japonica var. japonica, L. japonica var. hokurikuensis and L. kiusiana in evergreen forests. The newly described variety is distinguished from L. japonica vars. japonica, hokurikuensis, and kiiensis by having fully opened, larger flowers and an obtuse labellum apex.

• Magazine of the Korean Society of Agricultural Engineers
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• v.28 no.3
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• pp.79-88
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• 1986

Drought occurs most frequently and severely around transplanting season of the rice plants in Korea. Shortage of water due to drought for the paddy fields often delays transplanting, and less often the rice plants are subjected to water stress after delayed transplanting. The present study aimed at quantification of the rice crop loss due to delayed transplanting, different inten3ity of water stress, and the combined effect of delay in transplanting followed by water stress for better use of limited water for irrigation under drought. The rice variety Chucheong, a japonica, and Nampung, an indica x japonica, were grown, transplanted to 1/200 a plastic pots, and subjected to different timing of transplanting and degree of water stress under a rainfall autosersing, sliding clear plastic roof facility with completely randomized arrangement of 5 replications. The results obtained are summarized as follows: 1.Twelve days or 22 days delay in transplanting without water stress reduced rice yield by 25% and 43% in the japonica variety, and by 15% and 60% in the indica x japonica variety. 2.The 10 days or 20 days water stress developed without irrigation after drainage in the rice plants transplanted at proper time lowered the water potential at the paddy soil 10cm deep to -4 bar, and -12 bar and caused rice yield reduction by 14%, and 45% in the japonica variety and by 8%, and 50% in the indica X japonica variety. 3.The 12 days delay in transplanting and 10 days or 20 days water stress reduced rice yield by 39% and 59% in the japonica variety, and by 38% and 52% in the indica x japonica variety. The 22 days delay in transplanting plus 10 days water stress caused yield reduction by 76%, i.e. meaningless yield, in both varieties. 4.The intermittent irrigation just to wet the soil body for 10 days after 10 days water stress without irrigation increased rece yield by 12 to 16% compared to the rice plants water stessed without irrigation continuously for 20 days in both varieties respectively. 5.The above results suggest strongly 1) to transplant the rice plants at proper .time even with some water stress rather than delay for sufficient water from later rainfall, and 2) to distribute insufficient irrigation water to broader area of transplanted rice with limited irrigation for better use of limited irrigation water. A greater sensitivity of japonica variety to a moderate water stress than the indica X japonica variety during initial rooting and tillering stage was noticed. To cope with frequent drought in rice culture, firstly the lasting time of transplanting without yield reduction should be clarified by region and variety, and secondly a scheme of rational distribution of limited water should be developed by region with better knowledge on the varietal distribution of limited water should be developed by region with better knowledge on the varietal responses to varying intensity of water stress.

• Korean journal of food and cookery science
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• v.7 no.2
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• pp.1-6
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• 1991

The sensory properties and the change of lipid content of cooked rice were investigated to evaluate the effects of cooker (electric and pressure cooker) and variety ($Japonica and Indica\timesJaponica variety$). Overall preference of cooked rices were higher in the pressure cooker than the electric cooker. In the case of electric cooker, Japonica variety was prefered than $I\timesJ$ variety. Free lipid contents were reduced and bound lipid contents were increased after cooking. The bound lipid contents had a correlation with shiness of cooked rice(r=-0.69).

• Journal of Applied Biological Chemistry
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• v.50 no.3
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• pp.127-131
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• 2007

The properties of two cultivars of japonica rice, Odae (early ripening variety) and Ilpum (late ripening variety), were compared. They grew on MS (Murashige and Skoog) medium but the growth of both cultivars was strongly retarded by 50 mM or more salt. There was no clear difference between the growths of seedlings of the two cultivars for the first 24 h after germination. The amylopectin chain-length profiles of the two cultivars did not differ significantly, and amylopectin content was estimated at $16.0{\pm}0.4%$ in cv. Odae and $16.4{\pm}0.4%$ in cv. Ilpum. A total of 114 RAPD (randomly amplified polymorphic DNA) fragments ranging from 0.4 to 2.5 kb were isolated from the two cultivars, 61 from cv. Odae and 53 from cv. Ilpum, indicating that there is little genetic variation between them.

• Magazine of the Korean Society of Agricultural Engineers
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• v.28 no.2
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• pp.31-41
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• 1986

Knowledge of the degree of yield reduction due to water stress at different crop growth stages in rice production is important for rational scheduling of irrigation during periods of insufficient water supply. Previous studies to determine the degree of yield reduction duo to water stress suffered from interruptions by rain during experiment. Also the findings did rot relate the degree of water stress to the soil water potential and water deficit status of rice plants. In this study, two years experiments were conducted using the high yielding rice varieties, an Indica x Japonica (Nampoong) and a Japonica variety(Choochung). These were grown in 1/200$^{\circ}$ plastic pots placed under a rainfall autosensing, sliding clear plastic roof facility to control rainfall interruptions. The results obtained were as follows. 1.The two varieties differed in the growth stage most sensitive to water stress as well as the degree of yield reductions. When rice plants were stressed to the leaf rolling score 4 and soil water potential of about - 20 bar at major crop growth stages which included heading, booting, non-effective tillering, panicle initiation and early tillering stages, the yield reductions in the Indica x Japonica variety were 58%, 34%, 27%, 22%, and 21%, respectively, whereas in the Japonica vairety they were 23%, 36%, 1%, 13% and 22%, respectively. This result show that the recommended drainage during non-effective tillering is valid only for the Japonica variety. Sufficient irrigation at booting, heading and early tillering stages are necessary for both varieties. 2.The two varieties showed visible wilting symptoms when the soil water potential dropped to about - 3.0 bar. The Japonica variety showed more leaf rolling than the Indica X Japonica. However, it had a higher retention of leaf water content and greater stomatal diffusive resistance. When the soil water potential dropped, the Japonica variety showed leaf rolling score (LRS) 1 at 0 soil-5. 0 bar and LRS 2 at 0 soil -6.0 bar while the Indica X Japonica showed LRS 1 at 0 soil - 5.5 bar and LRS 2at 0 Soil - 9.0 bar. The stomatal diffusive resistance was maximum at the second top leaf blade in both varieties at intermediate water stress of 0 soil - 4.5 bar. 3.The number of days that was required for the soil water potential to drop to-3. 0 bar and to - 20.0 bar after drainage of irrigation water from the 20cm deep silty clay loam soil in the pots were 6 and 13 days, respectively for booting stage, and 7 and 11 days, respectively for heading stage, 9 and 12 days, respectively for panicle initiation stage, and 12 and 19 days, respectively for early tillering stage. 4.Water stress during the early tillering stage recorded the longest delay in beading time, the largest reduction in panicle numbers and a substantial yield decrease of 20%. This calls for better water management to ensure the availability of water at this stage, particularly during drought periods. In addition, a reexamination of the conventional inter-drainage practice during the non-effective tillering stage is necessary for the high yielding Indica X Japonica varieties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.3
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• pp.151-155
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• 2005

This study was carried out to get information for diversifying of resistant genes to bacterial blight (BB) in Japonica cultivar breeding programs. TWo hundred nine rice varieties were tested for qualitive resistance to four races of BB; HB9101 isolate for race K1, HB9102 isolate for race K2, HB9103 isolate for race K3, and HB01001 isolate for race K3a. Two hundred nine rice varieties were divided into five groups according to their race reaction. Fourteen Tongil-type varieties and ninetyseven Japonica varieties showed susceptible reaction to four races; Kl, K2, K3 and K3a. Thirteen Tongil-type varieties and thirty-one Japonica varieties were resistant to only one race; K1. Nine Tongil-type varieties and one Japonica variety were resistant to two races; K1 and K2. One Tongil-type variety and twenty-eight Japonica varieties were resistant to the three races; K1, K2, and K3. Fourteen Tongil-type varieties and one Japonica variety were resistant to four races; K1, K2, K3, and K3a. A number of Tongil-type varieties showed broad spectrum resistance to four races, while a number of Japonica varieties showed broad spectrum resistance to three races; K1, K2, and K3.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.18-22
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• 1977

Germination ability of a japonica and 15 indica$\times$japonica varieties was tested at day/night tempuratures of 25/2$0^{\circ}C$ and 12/12$^{\circ}C$. Germination ability of a japonica variety, "Jinheung" and two indican$\times$japonica varieties. "Suweon ＃251" and "Suweon ＃278" was greater than that of other indica$\times$japonica varieties tested. Germination pattern of varieties was made into 4 groups.ieties was made into 4 groups.

• Journal of Ecology and Environment
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• v.36 no.3
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• pp.173-181
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• 2013

Two varieties of Aucuba japonica differ in ways that can be considered adaptive to differing geo-climatic conditions in their respective distribution ranges. Irrespective of growth stage, the mean leaf size of A. japonica var. japonica was significantly larger than A. japonica var. borealis. Smaller leaf size and ultimately smaller stature of A. japonica var. borealis are an advantage under the higher snow load and lower temperatures in the forests along the East Sea where the variety grows. Snow load also acted as an important driving force for structural modifications of A. japonica var. borealis from cellular level in leaves to the organization of branch extension growth. Global warming by changing snowfall patterns in Japan may lead to range shifts in the two varieties of A. japonica.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.1
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• pp.14-19
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• 1980

The growth of rice variety 'Suweon 258' that is remote crossed variety between Indica and Japonica rice tended to be influenced more by air temperature than water temperature compared to Japonica variety 'Jinheung' that was influenced more by water temperature than air temperature during maximum tillering stage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.2
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• pp.203-210
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• 1976

To abtain basic information in process developing cold tolerance rice variety, used 8 varieties which are the close crossing and the remote crossing in order to clarify how is being the differences of low temperature injury in same variety and the varietal difference at each growth stage under the low temperature treatment, 18$^{\circ}C$-12$^{\circ}C$ (day-night), and to establish the effective testing method for low temperature injury in rice plant. In this experiment, the varietal ifferences of low temperature injury were significant in rice plant, and found out that low temperature injury at the each growth stage from sowing to heading in same variety was not horizontal.