• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.26-26
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• 2017

Seed germination stimulated by light is said to be photoblastism. Photoblastism has not been reported in cereal crops, especially in the rice, but Korean weedy rice was reported to have photoblastism and longer mesocotyl than cultivar. Photoblastic weedy rice (PBR) was used to identify QTLs for photoblastism and mesocotyl length. In previous works, QTLs for photoblastism, pbr1 and pbr12 were identified on chromosomes 1 and 12 using 124 F4 lines from a cross between Ilpum and PBR using bulked segregant analysis. Two QTLs for mesocotyl elongation, qMel-1 and qMel-3 were mapped on chromosomes 1 and 3 120 F8 lines from the same cross. Of interest, the RM8260-RM246 region of pbr1 overlapped with a region of qMel-1. To know whether these two QTLs are functionally related, 110 F3 lines were developed from a cross between Ilpum and CR7124. CR7124 having photoblastism and long mesocotyl was selected from 120 F8 lines. 95 F3 lines were measured for germination rate in a light and dark condition and mesocotyl length. Mesocotyl length and germination rate in the dark condition in F3 lines showed significant correlation (r = 0.7, P < 0.0001). 95 $F_3$ lines were genotyped with RM7419 on chromosome 1. ANOVA showed that RM7419 was tightly linked to QTLs for photoblastism as well as mesocotyl length on chromosome 1 (P < 0.0001) indicating the tight linkage of two QTLs. Fine mapping of the two QTL is underway to analyze their functional relationship.

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.04a
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• pp.282-283
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• 2000

• Weed & Turfgrass Science
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• v.6 no.3
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• pp.179-188
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• 2017

In order to provide basic data for efficient control of weedy rice, we analyzed emergence rate of 100 weedy rice genetic resources collected in South Korea according to growth temperature and soil burial depth. Analyzing of emergence rate using low dormancy weedy rice genetic resources, emergence was increased at 12 and $14^{\circ}C$ of mean temperature condition. When calculating the effective accumulated temperature above $10^{\circ}C$, emergence rate increased 0.6% and 0.5% in 1 cm and 3 cm of soil depth, respectively according to increase of $1^{\circ}C$. However it reduced as 0.28% in 5 cm of soil depth condition. Analyzing of emergence rate using high dormancy weedy rice, red rice showed 55%, 46%, 41% of emergence rate in 1 cm, 3 cm and 5 cm of soil depth condition, respectively. However those of white rice decreased as 10%, 8% and 5.7% in 1 cm, 3 cm and 5 cm of soil depth condition, respectively. Relative emergence, assuming the final emergence rate as 100%, reached 80%, 90% and 100% when effective accumulated temperature was $83-112^{\circ}C$, $100-123^{\circ}C$, $148-160^{\circ}C$ respectively.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.156-161
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• 2002

Two different cDNA clones for superoxide dismutase (SOD) were isolated from an weedy rice variety (Oryza sativa, cv. Bhutan14Ad) and were introduced into a cultivated rice variety (Oryza sativa, cv. Nakdong) in order to develop the environmental stress-resistant rice plants. Sequence analysis of the cloned cDNAS indicated that the deduced amino acid sequence of SOD-A is 88.4% identical to that of SOD-B. Furthermore, the nucleotide sequence of SOD-A is 99.3% identical to that of a Cu/Zn SOD gene of Oryza sativa (GenBank accession No. L36320). The nueleotide sequence of SOD-B was identical to that of the previously published SOD gene (Accession No. D01000). A cultivated rice variety, Nakdong-byeo, was transformed with chimeric SOD genes containing a actin promoter of rice and pin2 terminator using a particle bombardment technique. Transformed calli were selected on an selection medium containing phosphinothricin (PPT). Transgenic rice plants were regenerated from the PPT-resistant calli. PCR analysis with genomic DNAs from transgenic plants revealed that transgenes are introduced into rice genome.

• Proceedings of the Korean Society of Crop Science Conference
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• 1995.05a
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• pp.18-19
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• 1995

• Proceedings of the Korean Society of Crop Science Conference
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• 1999.05a
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• pp.65-66
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• 1999

• Proceedings of the Korean Society of Crop Science Conference
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• 2007.11a
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• pp.218.2-218.2
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• 2007

• Journal of Practical Agriculture & Fisheries Research
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• v.18 no.1
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• pp.93-100
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• 2016

This research was conducted to determine a pre-germinated herbicides with iron-coated seeds in water and wet hill seeded rice. Days of rice seedling emergence was the faster germination at the application of benzobicyclon > oxadiazon > thiobencarb > butachlor and the sealed iron-coated seeds with pre-germinated seeds> pre-germinated seeds> iron-coated seeds with pre-soaking. The seedling establishment was relatively high in untreated control and benzobicyclon among seed treatments by 63.7% and 75.7%. There was 100% seeds killed of pre-germinated seeds in terms of herbicide phytotoxicity and sealed iron-coated seeds with pre-germinated seeds in butachlor but benzobicyclon was of safe with 2% rice seeds killed. Infant rice seedling height was of 9.2-12.9cm in benzobicyclon and 11.9-16.3cm in untreated control and thus there was relatively normal development and growth at the initial rice seedling.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.299-310
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• 2019

The eating quality of rice is one of the main concerns of rice breeding programs in many countries, especially in japonica rice cultivation areas. To select new resources with high eating quality from Korean native japonica rice, we evaluated a total of 76 varieties, including 47 native rice resources (26 landraces + 21 weedy rice) of Korea. In this study, all eating quality traits varied widely among the native resources, and some of the native resources revealed a high evaluation score in the palatability, expected eating quality, and physicochemical traits among the tested whole-plant materials. From the results, we selected two landraces (Sangdo and Waebyeo) and three weedy rice varieties (Hoengseongaengmi3, Namjejuaengmi6, and Wandoaengmi6) as promising resources for improvement of rice eating quality. Specifically, Wandoaengmi6 presented potential as a key breeding material for improving the eating quality of Korean rice cultivars, having the best evaluation results in palatability score (PS 0.83) from the sensory test and glossiness value (GV 81.8) from the Toyo taste meter of cooked rice. Given the urgent need to overcome the constraint of the narrow genetic background of Korean japonica rice, the results could be a practical solution for exploring new opportunities for improving rice eating quality through the expansion of genetic resources.

• Korean Journal of Plant Resources
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• v.19 no.5
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• pp.612-616
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• 2006

In recent years, there has been increasing concerns in gene flow from GM crops to wild or weedy relatives as a potential risk in the commercialization of GM crops. To access the possibility of the environmental impacts by GM rice, small-scale experiments of gene transfer were carried out. Herbicide and drought stress resistant GM rice and non-GM rice Nakdongbyeo, wild rice Oryza nivara, and weedy rice Sharebyeo were used for artificial pollination experiments and bar gene was used as a tractable marker after pollination. The harvested putative hybrid seeds after artificial pollination were germinated and true hybrid plants were selected by basta treatment. The hybrid plants were verified again by PCR amplification of bar and trehalose-6-phosphate phosphatase (TPP) genes and RAPD PCR analysis.