• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.147-156
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• 1981

Most of the currently available rice threshers in Korea are of head-feeding type originally developed for threshing paddy at grain moisture content of 15 to 17% on wet basis. And prevailing rice harvesting system is swathing or cutting and bundling upright rice crop at a maturity stage of grain moisture content of ca. 28 to 20%, followed by transient natural drying in the field and threshing at grain moisture content of about 17%. The system often allows rather high field loss of rice both quantitatively and qualitatively. These necessitate use of a preharvest desiccant, and diquat has been registered recently as a rice desiccant. Aim of the present study is to determine the best time and rate of diquat application and to evaluate its utility as a rice desiccant under its optimal usage conditions in Korea. Diquat was not so effective for japonica rice varieties while it was very effective for the new varieties bred from indica x japonica crosses. The best time of application was the period from 2 days before to 3 days after physiological maturity of grain (moisture content of 28% w.b.) and the optimal rate was about 330g of diquat ion/ha. Applying diquat at the right time and rate dropped grain moisture to 15 to 16% (w.b.) within a week after treatment in contrast to that of 20 to 24% in untreated rice. Desiccation of rice crop with diquat resulted in 10 to 15% increase in grain resistance to shattering and significant reduction in percent green rice. However, there was no reduction in milled rice yield and percent whole kernel and was no change in the percent chalky rice and percent tinted rice. Diquat use appears highly desirable, if there is no residue problem which has not been studied in the present study.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.9
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• pp.1339-1347
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• 2008

The objective of this study was to determine the effects of green tea probiotics on growth performance, meat quality and immune response in finishing pigs, and to assess the possibility of substituting green tea probiotics for antibiotics in diets of finishing pigs. This green tea probiotics is made by mixing green tea powder and excipients (defatted rice bran and wheat bran) and fermenting the mixture with beneficial bacteria. A total of 90 crossbreed "Landrace$\times$Yorkshire" finishing pigs with an average body weight of $72.5{\pm}2.5kg$ were assigned to 5 dietary treatments in a completely randomized design. Each treatment had 3 replications with 6 pigs per replication. The five dietary treatments were control, antibiotic (0.003% chlortetracycline added) and 0.1, 0.5 and 1.0% of green tea probiotics. There were no significant differences in final body weight, daily weight gain, daily feed intake and feed conversion ratio in the green tea probiotics and antibiotic treatments (p>0.05). Crude protein content was significantly increased in the 0.1 and 1.0% green tea probiotics treatment groups (p<0.05) and there was no significant difference in crude fat content of the meat among the treatments. The TBA value of meat was significantly lowered with 0.5 and 1.0% green tea probiotics treatments compared to that of controls and statistically similar to the antibiotic treatment after 3 weeks of storage (p<0.05). The growth of spleen cells stimulated with Con A (0.1 and $1.0{\mu}g/ml$) was significantly increased with 1.0% green tea probiotics treatment compared to that of the control treatment (p<0.05). The growth of spleen cells stimulated with LPS (1.0, 3.0 and $10{\mu}g/ml$) was significantly increased in the 0.5% green tea probiotics group compared to the antibiotic group (p<0.05). In Con A ($1.0{\mu}g/ml$) medium, IL-6 production of spleen cells was significantly increased with 1.0% green tea probiotics treatment compared to that of the control (p<0.05). In LPS ($10.0{\mu}g/ml$) medium, TNF-${\alpha}$ production of spleen cells increased significantly in all green tea probiotics treatment groups compared to that of the control (p<0.05). Finally it can be summarized that addition of green tea probiotic has a positive effect similar to antibiotic and 0.5% is the suitable dietary supplementation dose for finishing pig production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.437-443
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• 1995

Concerns on use of excess amount of chemical fertilizier and pesticide in current farming system turns both of the producer and consumer of agricultural products to an organic farming which use a less chemicals and more natural manure. Rice-duck farming system is one of the strategy to meet the purpose and this experiment was carried out to find the effect of the rice-duck farming system on the quality and yields of rice. 20day-old rice seedling were mechanically transplanted in sandy-loam paddy field and 21 day-old ducks were raised from 3 weeks after transplanting with population of 30 heads per 10a. The plots were consists of reduce fertilizer(70%) with and without duck-raising. The conventional fertilizer treatment without duck-raising was used as check. The results obtained are summarized as follows. The weeds population of test plots which were raised with duck for 3 consecutive years was less than that of test plots without duck-raising, though a speciffic population of Echinochola crusgallis were increased. The weed control effect was higer in duck-raising than in check at the maximum tillering stage but, not at later stages of rice plant. It was found that the small animals and insects inhibiting in the rice field were reduced by duck-treatment, however, there were also damages of grass leaf roller at booting stage in the plots of duck-raising. In rice-duck plot, dark green leaf color were found: 41.8 of SPAD value than 38.6 of SPAD in check plot. Higher root activity and surface soil oxidation were also observed in rice-duck plot than check plot. 3% of the increase in yield was observed by duck-treatment. However, the expected increase of the palatability wsa not observed. This may be due to the unfavorable weather conditions during the rice growing in this expriment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.2
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• pp.85-94
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• 2022

The mixed cropping system is a centuries-old cropping technique widely practiced in farmers' fields worldwide. Increased plant diversity enhances farmland biodiversity, which improves grain yield and quality. However, the effect of growing different rice cultivars simultaneously has rarely been investigated. In the present study, six glutinous rice cultivars were selected, and two mixture cultivation methods were determined according to plant height, grain yield, and color. Colored and glutinous rice are used for specific purposes by consumers because of their color and nutritive value. Six glutinous rice varieties, including aromatic and colored rice, were included in the combination interplanting trials. The results showed that, compared with the corresponding monocropping systems, almost all combinations of the mixed cropping systems had advantages in yield-related traits. Compared with monocropping systems, mixed cropping systems increased the number of panicles per plant and maturation rate by 20% and 10%, respectively. An increase of 18-20% grain yield was observed in mixed cropping plots compared with that in plots which grew only a single rice variety. Some rice varieties, such as green colored rice 'Nogwonchall' and black colored rice 'Chungpunghukhayangchall', exhibited 18-22% increased yield when they were planted in combinations. The high yields were primarily owing to improved light interception and reduced lodging, although other factors (for example, reduced severity of disease) may have also contributed.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.7
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• pp.819-827
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• 2007

A numerical algorithm for estimating precise backscattering coefficients of rice fields is proposed and its accuracy is verified in this paper. After a bunch of rice plants above water surface is modeled with a bunch of randomly oriented lossy dielectric bodies above an impedance surface and the equivalent volume currents of the lossy dielectrics are computed using the moment method. Then, the scattered fields of a rice field with many bunches are computed with a Monte Carlo method, and consequently the backscattering coefficient of the rice field is computed for various incidence angles and polarizations. Finally, the backscattering coefficient of a rice field is measured at 1.85 GHz using an R-band scatterometer system, and these experimental data are used to verify the numerical algorithm proposed in this paper. It is found that the numerical computation results agree well with the measurement data.

• Korean journal of applied entomology
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• v.23 no.4 s.61
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• pp.233-236
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• 1984

Studies were conducted to investigate the effect of Carbofuran 3G on the density variation of rice pests and their natural enemies in case the insecticide was treated two times as compared with usual trials in paddy field. Even the two times application of Carbofuran 3G in the nursery boxes of machine transplanting and paddy water trials obtain same results to pests, small brown planthopper (Laodelphax striatllus), green rice leafhopper (Nephotettix cincticeps), brown planthorper (Nilaparvata lugens), white back planthopper (Sogotella furcifera), rice stem bore (Chilo suppressalis), rice stem maggot (Chlorops oryzae), rice thrips (cloethrips oryzae) as compared with usual trials. The density of natural enemies, spiders and egg parasite, Anagrus sp. of planthoppers in the two times application part of Carbofuran 3G increased 2.4 fold as compared with usual trials.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.4
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• pp.1-9
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• 1980

To determine the optimum harvest time of recent rice varieties from Indica/Japonica remote crosses, leading varieties Suweon 264 and Milyang 23 were tested for the changes in dry matter weight and moisture content of grain, shattering, shelling ratio, milling ratio, and apparant physical quality during grain development at 5 day-intervals from 20 days to 55 days after heading. The results are summarized as follows: 1. Grain weight (dry matter) reached its maximum (physiological maturity) at 30 days after flowering (DAF) in Suweon 264, and at 35 days in Milyang 23, and thereafter it did not change significantly until 55 DAF. 2. Time course of decrease in grain moisture content (Y, %) during maturation (X, DAF) consisted of two linear phases, i.e. a fast and a slow period: Y=68.245-1.33X until 34DAF, and Y=23.025-0.470X until 55DAF after 34DAF in Suweon 264; Y=73.62-1.634X until 24.5DAF, and Y=33.59-0.570X until 55DAF after 24.5DAF in Milyang 23. Two varieties showed the same grain moisture content of 28% (wet basis) at physiological maturity in spite of the distinct differences in the heading date, time of physiological maturity and thereby ripening climate. 3. Force to shatter a grain ranged about 90 to 100g in Milyang 23, and about 200 to 250g in Suweon 264 and in a Japonica variety, Jinheung. The force, however, did not change significantly with harvest time from 35DAF to 50DAF. 4. The changes in the ratios of shelling, milling, broken rice and tinted rice with harvest time were insignificant during a period from 35DAF to 55DAF. However, ratios of green rice and white belly rice decreased significantly with delay in harvest time during 10 days after physiological maturity. 5. The best time of harvest for maximum yield and good quality is thought to be 10 days after physiological maturity, and grain moisture content at this time was about 20% on wet basis.

• Korean Journal of Human Ecology
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• v.5 no.2
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• pp.9-21
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• 2002

This study was investigated traditional food utilization actual conditions of Gwangju and Chollanamdo. Frequency of main meal ice plain white rice, boiled rice and cereals, bean-mixed rice, gruel Dakjuk, winter squash porridge, sesame porridge, noodles by noodles cut out with a kitchen knife, noodles with assorted mixtures, soup with dough flakes order frequency much have. Soup ate much beanpaste soup, soup cooked with dried radish leaves, seaweed soup, broth by power-pot soup, hot shredded beef soup, loach soup order. Pot stew soybean paste stew and kimchi stew, beef casserole bean curd beef casserole and small octopus beef casserole often eat. Kimchi ate much cabbage kimchi, radish kimchi, radish cube kimchi, dish of dried slices of radish by sesame leaf dish of dried slices of radish, pickled garlics, Maneuljjong dish of dried slices of radish order. Salted sea foods that eat often were salted anchovies, tiny salted shrimps, Gejang order, and soy sauce were toenjang, korean hot pepper paste, bean-paste soup prepared with around fermented soy beans order, and laver fried kelp, tangle fried kelp, green perilla leaf fried kelp order to fried kelp, and it was bean sprouts, bracken herbs, fragrant edible wild aster herbs order to herbs. It is Ssukgatmuchim, squid debt saliva, Jabanmuchim's order that season, hard-boiled food is beef boiled in soy sauce, mackerel radish hard-boiled food, order of bean curd hard-boiled food, panbroiling ate often by order of Kimchi panbroiling, red pepper anchovy panbroiling, pork panbroiling. Steamed dish is egg steamed dish, fish steamed dish, steamed short-ribs order, fried fish egg speech, by Gimchijeon, Pajeon order, meat roasted with seasoning ate often by laver meat roasted with seasoning, hair-tail meat roasted with seasoning, mackerel meat roasted with seasoning order. Minced raw meat are small octopus raw that live, beef dish of minced raw beef, Hongeohoe order, rice cake is cake made from g1u1ions rice, Seolgitteok, songpyon order, dessert ate often by fermented rice Punch, cinnamon flavored persimmon punch, Kangjung order.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.2
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• pp.89-93
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• 2004

This experiment was conducted to investigate the variation of nitrogen use efficiency, nitrogen uptake efficiency, physiological utilization efficiency and their relationships with growth characteristics in the 28 Korean rice cultivars. Nitrogen use efficiency of 28 rice cultivars was 47.74, nitrogen uptake efficiency was 0.71, and physiological utilization efficiency was 68.76 in average. Nitrogen use efficiency of rice cultivars had low variation ranged from 44.09 to 51.91, but nitrogen uptake efficiency were relatively high variation from 0.51 to 0.90, and physiological utilization efficiency was from 51.71 to 94.26. The high efficient group in nitrogen uptake efficiency whose value was calculated above 0.80 included Daeanbyeo, Seojinbyeo, Ansungbyeo, Dongjinbyeo, and Hwaanbyeo, while the low efficient group with below 0.60 was Kwanganbyeo, Sampyeongbyeo, Soorabyeo, and Hwasungbyeo. Hwasungbyeo, Sampyeongbyeo, Soorabyeo for physiological utilization efficiency were more efficient cultivars, while Daeanbyeo, Seojinbyeo, Ansungbyeo were less efficient cultivars. Nitrogen uptake efficiency had positive correlation coefficients between dry matter weight of plant ($0.842^{**}$), leaf area index ($0.761^{**}$), and leaf nitrogen content ($0.599^{**}$), respectively. Therefore, the dry matter weight of rice plant and leaf area index was important characters to evaluate nitrogen uptake efficiency in rice cultivars. Also, more efficient cultivar in nitrogen uptake had higher chlorophyll meter value, which was appeared dark green color.

• Korean journal of applied entomology
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• v.15 no.4 s.29
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• pp.179-184
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• 1976

Laboratory experiments were conducted to clarity the early-spline host·selectivity by the small brown planthopper(SBPH), Laodelphax striatellus Fallen, and green rice Leafhopper(GLH), Nephotettix cincticeps Uhle., on the bailey (the variety Suweon #18) and water foxtail (Alopeculus aequadis Sosbol). The host selectivity was evaluated on the bases of feeding and ovipositional perferences of the insects on the plants and their biological effects on the plants. The nymphs of SBPH much more preferred barley for feeding than water forxtail, while the nymphs of GLH relatively prefered water foxtail. There was no significant difference in ovipositional preference by SBPH among the test plants, and ovipositional preference by GLH Ivas significantly lower on barley and water foxtail than on rice. Nymphal growth an4 adult emergence of SBPH were significantly faster and higher on barley than on water foxtail. No adult emergence of GLH was observed on barley, and adult emergence was still quite lower even on water foxtail. The adult of SBPH fed on barley showed longer longevity aad higher fecundity than that of SBPH from water foxtail and rice. The adult GLH fed ell water foxtail shorted relatively shorter longevity and to)ver fecundity than that of GLH on rice. In conculsion, barley seems to be more adequate for spring host of SBPH than water foxtail, but barley may not be quite adequate for spring host of GLH. At presont moment, GLH seems rather to primarily select the water foxtail than barley as a spring host, even if the water foxtail is not so adequate for development of GLH.