• Mycobiology
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• v.38 no.2
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• pp.97-101
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• 2010

Calocybe indica, a tropical edible mushroom, is popular because it has good nutritive value and it can be cultivated commercially. The current investigation was undertaken to determine a suitable substrate and the appropriate thickness of casing materials for the cultivation of C. indica. Optimum mycelial growth was observed in coconut coir substrate. Primordia initiation with the different substrates and casing materials was observed between the 13th and 19th day. The maximum length of stalk was recorded from sugarcane leaf, while diameter of stalk and pileus, and thickness of pileus were found in rice straw substrate. The highest biological and economic yield, and biological efficiency were also obtained in the rice straw substrate. Cow dung and loamy soil, farm-yard manure, loamy soil and sand, and spent oyster mushroom substrates were used as casing materials to evaluate the yield and yield-contributing characteristics of C. indica. The results indicate that the number of effective fruiting bodies, the biological and economic yield, and the biological efficiency were statistically similar all of the casing materials used. The maximum biological efficiency was found in the cow dung and loamy soil casing material. The cow dung and loamy soil (3 cm thick) was the best casing material and the rice straw was the best substrate for the commercial cultivation of C. indica.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.59-62
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• 1988

The correlations of rice properties and the texture characteristics of hot($70^{\circ}C$) and cold($20^{\circ}C$) cooked rice were investigated with Japonica and J/Indica rice each of 6 varieties. No significant differences in textural properties between Japonica and J/Indica cooked rices were observed. The hardness of cold cooked rice was positively correlated with setback(r=0.613) of rice flour but not correlated with amylose content and the other chemical properties of starch or rice flour.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.170-174
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• 1977

The comparative effect of washing on the loss of nutrients in rice was studied with regard to varieties of Japonica and Indica type and various polishing degrees. Washing procedure was made by usual method for the preparation of cooked rice. The average loss was 1-2% of total solid, 5-7% of protein, 18-26% of calcium, 19-47% of iron, 22-40% of vitamin $B_1$, 11-24% of vitamin $B_2$ and 36-45% of niacin during washing in the 50-90% polished rice of Japonica and Indica varieties. The Indica rice had relatively higher loss of total solid, protein, calcium and iron than that of Japonica rice. The loss of total solid, N-free extract and vitamin in 70% polished rice was lower than that of 90% polished rice. Loss of lysine in 90% polished rice amounted to more than 6% and was higher than the loss of other amino acids.

• Applied Biological Chemistry
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• v.28 no.2
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• pp.106-109
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• 1985

Gelatinization of Japonica(30 varieties) and J/Indica(22 varieties) rice flours in 0.2N NaOH was examined. J/Indica rice flours were easily gelatinized and showed higher viscosities at all reference points than Japonica counterparts. Viscosity development rate was not correlated with protein or amylose content. Only J/Indica rice varieties showed positive correlation between hydration rate and viscosity development rate.

• Food Science and Preservation
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• v.20 no.3
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• pp.365-371
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• 2013

The organic acids, fuel oil contents and antioxidant activities of Yakju with the addition of rice varieties were investigated. The rice cultivars that were used in this study were Ilmi rice, Hopyung rice, Hopum rice, Hanarum rice, Anda rice and Indica rice. The study results are as follows: the pH values of Ilmi Yakju and Hanarum Yakju were 4.14 and 4.07, respectively, and those of the other Yakjus, 3.92~3.98. The total titratable acid content of the Yakju for which Indica rice was imported from Thailand was highest among the samples. The reducing sugars content of the Yakju for which Indica rice was used was higher than that of the other samples. The ethanol content of the Hanarum Yakju was higher than that of the other Yakjus, and the lowest ethanol content was found for the Indica Yakju. The major organic acid component of the Yakju was lactic acid. The total organic acid content was highest in the Indica rice Yakju. The amounts of the following main fusel oils were highest, in the following order: 2-butyl alcohol, 2-pentanol, N-propyl alcohol, acetaldehyde, ethyl acetate, methyl alcohol and 2-methyl-1-propyl alcohol. The DPPH free radical scavenging activity of the Indica rice Yakju was much higher than that of the Ilmi rice Yakju and the Hanarum rice Yakju. Also, the SOD activity of the Indica rice Yakju was strongest among all the samples. The total polyphenol content of the Indica rice Yakju was the highest among all the samples.

• Weed & Turfgrass Science
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• v.1 no.4
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• pp.31-37
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• 2012

This study was conducted to make the rice yield prediction model system as affected by densities of Aneilema keisak and Aeschynomene indica and to determine their economic threshold levels in flooded direct-seeded rice. When the density of A. keisak was 8 plants per $m^2$, the yield of rice reduced to 8% and as the density increased up to 96 plants per $m^2$, the reduced rate of rice yield reached to 45% and in A. indica, the reduced rate of rice yield were 20 and 77%, respectively. The rice yield loss models of A. keisak and A. indica were predicted as Y=553.2 kg (1+0.00913X), $R^2=0.912^{**}$ and Y=567.9 kg/(1+0.04434X), $R^2=0.961^{**}$, respectively. Economic threshold levels calculated using cousens' equation were 3.0 plants per $m^2$ in A. keisak and 0.6 plants per $m^2$ in A. indica.

• Plant Breeding and Biotechnology
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• v.5 no.4
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• pp.371-389
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• 2017

Supplying sufficient rice to growing populations is a global challenge. Hybrid indica rice varieties exploiting heterosis have increased yields, but inter-subspecific crosses between indica and japonica varieties are hampered by sterility. Examination and genetic understanding of yield heterosis in indica/japonica crosses addressing yield barriers are basic requirements. In this study, QTLs for heterosis of yield traits were identified in indica-japonica recombinant inbred lines (RILs) using a total of 178 RILs originating from Dasanbyeo (indica) ${\times}$ TR22183 (japonica) (DT-RILs) and their backcrossed populations. Nine of sixty-six major quantitative trait loci (QTLs) identified in DT-RILs exhibited heterosis. Heterosis QTLs clustered with other traits on chromosomes 1, 4, and 8, and clusters were conserved between different RILs. The clusters contained several known yield enhancement genes/QTLs. Specific heterotic allele combinations contributed to four major heterosis QTLs, particularly for panicle and spikelet number traits. Heterosis for yield and yield-related traits was explained by the harmonized effects of overdominance, dominance, and epistatic interactions in inter-subspecific breeding populations.

• 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 Science and Technology
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• v.20 no.3
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• pp.331-337
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• 1988

The thermal properties of typical five Indica and five Japonica rice varieties were investigated by Differential Scanning Calorimetry (DSC). There was no significant difference in gelatinization temperature between Indica and Japonica varieties, but the average enthalpy of gelatinization was larger in Indica types than that in Japonica. However, the enthalpy of melting of amylose-lipid complex was larger in Japonica types than that in Indica types. The DSC thermogram of hydrolyzed rice residue included a smaller peak of gelatinization with narrow range of temperature. Retrogradation of gelatinized rice kernel was also determined with DSC theremograms. The endothermic peak areas clearly increased with increasing storage time at $4^{\circ}C$ so that the area could be used as a measure of the relative degree of retrogradation. The results indicated that Samgang variety(Indica) retrograded more rapidly than Chuncheong variety(Japonica).

• Journal of Plant Biotechnology
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• v.33 no.4
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• pp.257-262
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• 2006

The paper evaluated the behavior of in vitro culture responses from a diverse set of Indica rice (Oryza sativa L.) genotypes. Significant differences were found in embryogenic callus induction frequency, callus growth and plant regeneration frequency when mature embryos of 11 cultivars, breeding lines and land races were compared. Genotype as well as plant growth regulator influenced the plant regeneration frequency. Callus induction frequency was not correlated with callus growth as well as plant regeneration frequency. The regenerated plants could grow to normal, fertile plants after they were successfully established in soil.