• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.38-43
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• 1999

Over 2,000 ha of rice fields in the western and southern coastal region of Korea were flooded with sea water during the spring tide, on August 19-21, 1997, and the rice plant at heading stage was injured. The field surveys were undertaken at the sea water flooded paddy fields in Chonbuk Province, to identify the injury symptoms and rice yield damage subjected to different flooding condition and desalinization methods. Five days after sea water flooding at heading stage, the flag leaves of rice plants flooded with 30 ㎝ deep sea water withered from the tip, the withering progressed to the lower leaves in deeper flooding. The spikelets were spotted black and discolored from the tip at 50 ㎝ deep flooded rice, and some panicles changed to white at 80 ㎝ deep flooded rice. Most of the rice leaves submerged completely for an hour were withered and most of panicles changed to white. The milled rice yield, percentage of ripened grain, and 1000 grain weight of flooded rice decreased with deeper flooding water, higher water salinity and longer flooding time. Even under the same flooding conditions, the damage of rice yield varied with the growth stage: heading stage>dough stage>booting stage. Rice yield damage was less in the fields on the upper riverside than those of the fields on the estuary and seaside, because of lower water salinity. In a flooded field, the rice yield damages were reduced as the distance increased from the levees where the sea water inflowed and increased as the distance increased from the fresh water irrigation gate. The desalinization treatments consisting of frequent exchange of irrigation water and spraying with fresh water soon after flooding effectively reduced the rice yield damage.

• Research in Plant Disease
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• v.16 no.2
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• pp.183-190
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• 2010

During the period from 1999 to 2008, we surveyed the major diseases incidence of rice in Korea. Leaf blast showed 0.85% of the diseased leaf area in 2000 and then consistently decreased to 0.02% by 2008. However, panicle blast irregularly appeared by the years depending on weather conditions for disease development from heading to milk stage of rice. Diseased lesion height of sheath blight had the lowest (10.1%) incidence in 2001 and the highest (21.4%) incidence in 2007. A negative corelation ($r=-0.88^*$) was measured between diseased lesion height of sheat blight and sunshine hours from mid- to late August. In Chunbuk, Gyeongbuk, and Gyeongnam provinces, brown spot occurrence declined since 2001, however, in Chungnam, Jeonbuk, and Jeonnam provinces, it increased since 2005. False smut drastically decreased after showing the highest incidence of 7.59% in panicles in 2000. The correlation coefficient between diseased panicles of false smut and rainfall during the late August was calculated as $0.94^{**}$. Bacterial leaf blight severely increased in the chronically infested fields in Jeonnam, Jeonbuk, Gyeongnam, and Chungnam province since 2003.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.363-370
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• 2014

We grew seedlings of Saechucheongbyeo and Odaebyeo of rice cultivars that are cultivated dominantly in the northern and middle regions of Korea under control(ambient condition), ambient $CO_2$ concentration+elevated temperature, and elevated $CO_2$ concentration+elevated temperature in order to study how growth responses and crop yield of major rice of Korea change as the global warming proceeds and compared the results. Aboveground biomass, belowground biomass, total biomass, and panicles weight per individual and ripended grain rate of cv. Saechucheongbyeo were the highest under control, but those of cv. Odaebyeo were the highest under elevated $CO_2$ concentration+elevated temperature. There was no difference in the number of panicles per individual of cv. Saechucheongbyeo and cv. Odaebyeo in these experiments. There was no difference in the number of grains per panicle of cv. Saechucheongbyeo among three environmental gradients, but that of cv. Odaebyeo was the highest under elevated $CO_2$ concentration+elevated temperature. Weight of a grain of cv. Saechucheongbyeo was highest under elevated $CO_2$ concentration+elevated temperature, but that of cv. Odaebyeo was the higher under ambient $CO_2$ concentration+elevated temperature and elevated $CO_2$ concentration+elevated temperature. Thus, if global warming continues in Korea, selection of rice cultivation varieties must be chosen carefully for commendation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.4
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• pp.38-44
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• 1979

$^14$C-sucrose was labeled on detached panicles and $^14{CO}_2$ on flag leaves or panicles of intact plants to study grain sink activity in spring oats cultivar Pennfield. Defoliation and emasculation experiment was conducted to study source-sink relationship during grain filling. Specific activity of groat rose up to 15 days after anthesis and declined rapidly to 18 days. Daily gain of groat wt. matched closely with specific activity of. groat during grain filling. Primary groats were higher in specific activity of groat than secondary groats.$^14{CO}_2$ exposure on panicle was three times higher in specific activity of groat than $^14{CO}_2$exposure on flag leaf. In the defoliation and emasculation experiment, groat wt. of Pennfield oats decreased as ratio of source/sink decreased. Half number of spikelets with half leaf area was no different in groat wt. compared to control, but normal number of spikelets with zero leaf area was decreased 16% in groat wt., indicating a significant compensation by green area on panicle.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.403-414
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• 2020

Gradient concentrations of Tithonia diversifolia green leaves and phosphate rocks were used to investigate their contributions as a fertilizer to the yield and quality improvement of a rainfed rice cultivar. Six treatments were compared: (1) T0, no fertilization (control); (2) T1, 1.28 g of phosphate rocks; (3) T2, 250 g of organic matter; (4) T3, 500 g of organic matter; (5) T4, 250 g of organic matter + 1.28 g of phosphate rocks; (6) T5, 500 g of organic matter + 1.28 g of phosphate rocks. The results showed that the germination percentage recorded 15 days after sowing varied from 58 - 76% between T0 and T5. The number of panicles ranged between 2 (T0) to 6.3 (T5). Moreover, the recorded length of the panicles ranged between 7.5 (T1) to 15.8 cm (T2), and the number of grains per panicle ranged between 25.5 (T1) to 273.5 (T3). The plant height was significantly increased in the T5 (79.27 cm) group compared to the T1 (33.63 cm) and control treatment (T0) (40.08 cm) groups. Although the plant height in the T2, T3, and T4 groups was slightly lower than the T5 group, the difference was not statistically significant. The average of the grain number per plant was high in the T3 (273.6 grains) group compared to the T1 and T0 (25.5 and 32.8 grains) groups, respectively. These results suggest that the combination of T. diversifolia leaves and phosphate rocks as a natural fertilizer would be beneficial when integrated into soil fertility management strategies and would contribute to improving crop yield and quality.

• Korean Journal of Soil Science and Fertilizer
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• v.3 no.1
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• pp.29-34
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• 1970

This experiment was conducted to investigate the influence of amounts of lime dressed on the growth of rice by the treatment of percolation and nonpercolation in the acid sulphate soil. And also analysis of soil chemical components after treatment was carried out. The results obtained were summarized as follows: 1. In the initial stage of growth, number of tillers and plant length showed no distinct differences between the treatments of percolation and nonpercolation, but after August the effect of lime appeared and the percolation treatment was more effective than the nonpercolation. 2. Lime dressing affected good influence on the panicles, grain per panicles and the rate of grain formation, and the treatment of percolation showed better results than nonpercolation. 3. If the yield of rough rice in the control (nonpercolation and lime dressing) was 100, it was 194 in the treatment of nonpercolation 12me/100gr of lime dressed, 268 in the treatment of percolation-4me/100gr of lime and 315 in the 8me/100gr-percolation. 4. Lime dressing affected good influence on the control of Helminthosporium leaf spots. 5. In the case of lime dressing, amounts of available phosphate and soluble silicon dioxide were increased, but ferrous ion ($Fe^{{+}{+}}$) were decreased.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.4
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• pp.177-181
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• 1975

The pot experiment was conducted primarily to clarify the relationship between lime application and they amount of potassium for the basal and top dressings on paddy rice. (Orizae sativa L. cultivar; variety Jinheung) The soils mixed with lime and without lime were separately filled in to 0.2827 a. open-bottom concretepots. The soil with lime was treated with slaked lime, at two weeks before transplanting to correct soil pH. around 7.0. The total amount of potassium 12 kilograms per 10a was applied by two or three split doses during transplanting, 19 days after transplanting and primodial stages. The results of experiment obtained are summarized as follows: 1. The application of potash in the rate of 4kg per 10a or less for basal dressing and the remaining amount of potash for top dressing at 19 days after transplanting and primodial stage or one top dressing, at primodial stage have increased the yield of paddy with increased number of panicles per hill, milliequivalent ratio of $K^-/Ca^{++}+Mg^{++}$ in leaves in the later stage of growth, number of ripened grains per panicle, and rate of grain maturity. 2. On the other hand, the greater the amount of potassium given for the basal dressing (over 4kilograms per 10a), the smaller number of tillers and panicles were resulted. And the tendency was considered chiefly due to high salt concentration at the early stage of rice growth.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.5
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• pp.431-435
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• 1992

This experiment was carried out to evaluate Korean red rices as useful genetic resource. Semi-wild red rices were collected from farmer's field of the Korean peninsula from 1988 to 1991. The collected red rices were classified into two groups according to length /width ratio of paddy rice and ecological characters. One was long grain red rice and the other was short grain red rice. Those were evaluated in yield components, culm length and panicle length. Mean number of panicles per hill of collected long grain red rices was 21.5 and that of short grain was 11.8. Number of spikelets per panicile of the long and short grain red rices were 86.1 and 108.7, respectively. 1000 grains weight of long grain was 20.1g and that of short grain was 20.2g. Spikelet fertility of long and short grain were 80.4% and 79.4%, respectively. Culm length of long grain was 103.6cm and that of short grain was 94.8cm. Panicle length of long and short grain were 22.1cm and 21.3cm, respectively. Number of panicles per hill, number of spikelets per panicle and culm length were significantly different between the two groups, however no differences, in panicle, length and seed fertility were found between the two groups.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.1-29
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• 1969

Experiments on rice concerning it s varieties, fertilization, seedling dates and herbicides have been conducted to determine the most desirable method of direct sowing cultivation on dry paddy field land in the middle part of Korea. The results obtained at the Office of Rural Development of Choongnam Province are as follows:. 1. Sixteen different derivatives from the main varieties of low land rice were cultivated on a dry paddy field by the direct sowing method; at the same time, a few varieties were tried adopting the common transplanting cultivation method. The yield and yield factors from these two groups were examined to give the following results: a) Compared to the common transplanting cultivation, the direct sowing method showed remarkably increased number of panicles while the number of flowers per panicle was shown to be significantly decreased. The maturing ratio was detected to be lowered. The yield horn them differed according to the different varieties : good yield was obtained from Hokwang while Norin ＃25 proved poor when compared with the common transplanting cultivation method. b) Among sixteen varieties tested, Sunsou, Norin ＃25, Jaigou, Hokwang, Palkueng and Gosi showed comparatively high yields, their yield being more than 325 kilograms per 10 Are, but Nampoong, Paldal, Nongkwang, Norin ＃29, Eunbangju ＃101 and Shiro gane showed less yield, their yield being less than 271 kilograms per 10 Are, the relations between the yield and the yield factors can be summarized as follows; Number of varieties and their rice yield. 1) The varieties which were great in the, number of panicles and high in yield=Jaigoun, Hokwang Palkueng and Gosi. 2) The varieties which were low in the number of panicles and high in yield=Sounsou and Norin ＃25. 3) The varieties which were great in the number of panicles and poor in yield=Eunbangju ＃101 and Sirogane. 4) The varieties which were poor in the number of panicles and poor in yield: Nampung, Paldal and Norin ＃29. Number of flowers per panicle and yield. 1) The varieties which were great in the number of flowers per panicle and high in yield: Sounsou, Norin ＃25 and Gosi. 2) The varieties which were poor in the number of flowers per panicle and high in yield ; Jaigoun, Hokwang and Palkueng. 3) The varieties which were great in the number of flowers per panicle and poor in yield: Paldal and Nampung. 4) The varieties which were poor in the number of flowers per panicle and poor in yield: Norin ＃29. Eunbangju ＃101 and Sirogane. Maturing ratio and yield. 1) The varieties which were high in the maturing ratio and high in yield: Jaigoun, Sounsou, Norin ＃25 and Palkueng. 2) The varieties which were low in the maturing ratio and high in yield: Hokwang and Gosi. 3) The varieties which were early maturing rat io and low in yield: Hokwang and Gosi. 4) The varieties which were late maturing ratio and poor in yield: Eunbangju ＃101, Nampungand Sirogane 1, 000 grain weight and yield. 1) The varieties which were heavy in 1, 000 grains weight and high in yield=Norin ＃25 and Hokwang. 2) The varieties which were light in 1, 000 grains weight and high in yield=Sounsou and Jaigoun. 3) The varieties which were heavy in 1, 000 grains weight and poor in yield=Nongkwang and Eunbanju. 4) The varieties which were light in 1, 000 grains weight and poor in yield=Norin ＃29 and Sirogane. 2. The experiment on fertilization showed that the most desirable amount to be given per 10 Are was 10 kilograms of Nitrogen, 5 kilograms of phosphate and 6 kilograms of potassium; and when the Nitrogen given exceeded 8 kilograms, its effect was better when given in amsll consecutive (split) amounts, while the maturing ratio and the number of the flowers per panicle increased when Nitrogen was given in large amount during the later stage of growth of rice. 3. The experiment on the date and amount of seedling showed that the tested variety, Sunsou gave the best results when planted on the days between 25 April and 10 May. Eight liters per 10 Are were preferable if planted early and 12 liters per 10 Are if planted late. The reason why the later planting gave a lower yield was that the number of flowers per panicle was fewer. 4. The experiment on the irrigation for rice with direct sowing cultivation immersed in water showed that it was the most satisfactory when irrigated on 25th June, 55 days after its seedling, its plot giving the best yield. The plots 10th June and 15th July showed just as good results. However, irrigated later, than 15th July it showed lower yields. 5. Compared to the yield of the plot controlled by the common method, the yield from the plots treated with chemical herbicide such as LOROX, TOK, PCP, SWEP, Mo-338 on dry condition soil seemed poorer, but significant difference was not found statistically. On the other hand in the case where chemical herbicides such as TOK, Mo-338, Stam F-34 or ORDRAM were used after irrigation, the yield from the ORDRAM and TOK treated plots did not show significant differences compared to the common hand weed controling method, but those treated with chemicals other than the above showed a lower yield.

• MALSORI
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• no.37
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• pp.73-85
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• 1999

The prosodic characteristics of Korean particles in read speech were examined in this paper based on K-ToBI labeling system in order to see whether they are prosodically weak form like functions words in English. Acoustic measurements and statistical analysis were done focusing on the distribution of particles over a variety of prosodic positions, prosodic positional effects on the phonetic realization of particles, and acoustic strength of particles compared to those of their surrounding syllables. The panicles were distributed rather equally over all 4 prosodic positions with the highest frequency at IP-medial/AP-final position and the lowest at IP-medial/AP-medial position except that topic marker 'Un/nUn' showed preference for IP-final/AP-final position. There was a significant prosodic positional effect on the duration and F0 of the particles. Duration was the longest at IP-final/AP-final position and interestingly, at IP-medial/AP-medial position while F0 was the highest at IP-final/AP-medial Position as expected. The comparison of the acoustic properties of the particles with those of neighbor syllables showed that duration was generally significantly longer and energy also showed larger values, if not significant, in particles suggesting that the particles in Korean are not prosodically weaker like function words in English.