• Journal of The Korean Society of Grassland and Forage Science
• /
• v.4 no.1
• /
• pp.62-69
• /
• 1983

This experiment was carried out to find the effect of seeding rates and herbicides on the weed control, yield and crude protein of sorghum-sudangrass hybrid (Sorghum bicolor (L.) Moench). The variety used in the present study was Pioneer 988. Two different seeding rates were 25 kg/ha and 50 kg/ha and five weed control treatments were weedy check, hand weeded check, alachlor, alachlor+simazine, and simazine of preemergence application. The results of this study are summarized as follows: 1. Forage yield was not influenced by seeding rates. There was no significant difference between forage yield from 25 kg/ha and from 50 kg/ha of seeding rates. But weedy plots showed higher yield from the high seeding rate. Alachlor+simazine treatment showed the greatest yield among the weed control treatments. But there was no difference among the hand weeded treatment, simazine treatment, and alachlor+simazine treatment. 2. Seeding rates did not affect weed yield, but weedy plots showed the tendancy toward higher weed yield from the low seeding rate. Alachlor+simazing preemergence application showed the most effective weed control. But there was no significant difference in weed yield among the treatments of the hand weeded, alachlor+simazine and simazine. The weed yield in alachlor treatment was significantly higher than other three treatments. 3. The height of plant was shortest on the weedy plots and the longest height was obtained from the alachlor+simazine application. But in the first harvest the height was reduced by herbicides. Seeding rates did not affect the plant height. But the height was slightly taller under the low seeding rate than under the high seeding rate. 4. The percent crude protein of the forage did not affected by two seeding rates. Simazine treatments increased the percent crude protein and total crude protein yield. Simazine and alachlor+simazine application showed the significantly higher percent crude protein than hand weeded and alachlor treatments. Simazine increased the percent crude protein without reduction of forage yield. 5. Whereas the number of original stand was greater in the high seeding rate, the number of tillers per stand was higher in the low seeding rate. Weed reduced the number of stands and tillers. There was no significant indifference among the weed control treatments. It is concluded from above results that when sorghum-sudangrass hybrids are broadcasted for forage, 25 kg/ha rate of seeding is appropriate and alachlor+simazine treatment is most effective on weed control, maximum forage yield, and high percent crude protein.

• The Journal of Natural Sciences
• /
• v.5 no.2
• /
• pp.49-62
• /
• 1992

This study was carried out to investigate the emergence, growth and yield components in rice inassoccation with Several cultivation methods direct sowing flooded paddy field(DSF), direct sowing by airplane(DSA), direct sowing in dry paddy field(DSD), 8days seedling planting(8DS), and 35days seedlingplanting(35DS). Also this study was attempeted to know the effects of calcium peroxide on germinationand early growth of rice under different soil conditions, seeding depth, application of organic matter,indirect sowing flooded paddy field.1. Rate of emergence was 73% in DSF, 70% in DSA, 62% in DSD, respectively, under the different cultivation method of rice in reclaimed paddy field.2. Degree of lodging in relation to cultivation was 5 at both DSF and DSA, 3 at DSD, 2 at both 8DS and 35DS respectively.3. Maximum tiller number was 568 per m2 at DSF and 527 at DSA. Heating was delayed for 4 days at DSF, 8 days at DSD and 2 days at 8DS as comparison with that at 35DS.4. Yield was higher 1% to 3% at DSF than that at DSA and DSD while decreased by 12% as compared with that of seedling planting.5. Total dry weight of seedling was decreased by 57% at 8DS, 60% at DSF 63% at DSD, respectively, under 0.3% of salinity. Ratio of decreasing in dry weight was higher with high salinity.6. The amount of O2 released was recorded highest to 2 to 3days after irrigatition, thereafter remaining constant to 10 days after irrigatition.7. The optimum coating amount of calcium peroxide for germination was a half of rice seed weight with 1 cm sowing depth and one-fold with 2-cm sowing depth when rice straw was not applied. With rice straw applied, on the other hand, the amount of peroxide was one-fold with 1-cm sowing depth. It was found that, under the condition of applied 600kg/10a, of 2-cm soil depth with rice straw calcium peroxide coating had no effect on emergence of rice seedling.8. In reclaimed paddy field, lodging degree was 7 with direct sowing by machine and 9 with direct sowing by hand.9. Yield was increased by 5% by applying rice straw with direct sowing by machine.

• Korean Journal of Environmental Agriculture
• /
• v.22 no.2
• /
• pp.79-86
• /
• 2003

This research was conducted to present reference data to be used as newly reclaimed tidal land management. We investigated vegetation succession at 4 reclaimed/reclaiming project areas and discussed relationship with soil and vegetation trhrough investigation and analysis soil chemical characteristics at 2 areas. 14 families 58 kinds were investigated. Vegetation were variou at Dea-Ho conservation polt and Seok-Mun National Industrial Area which are maintaining naturally. Vegetation were simple at Hong-Bo and Dongjin and MinKyong river areas which effected sea water. Common species that were investigated at 9 sites were Suaeda asparagoides, Aster tripolium, Phragmites australis, Suaeda maritima, Suaeda japonica, Carex scabrifolis. As soil desalinization progressing, soil classified at first saline-soidc soil, the nest saline soil and then normal soil. Chenopodiaceae revealed at about 30 dS/m of soil ECe and existed to 10 dS/m of soil ECe. At about 20 dS/m of soil ECe. Aster tripolium, Calamagrostis epigeios, and Sonchus brachyotus revealed and then non-halophytes and common plants at inland revealed at low soil ECe of about 10 dS/m. However it was not to progress vegetation sucdession and soil desalinization at the same time, owing to input of seeds or plants ect from out-ecosystem. So for promotion of vegetation at newly reclaimed tidal land, we proposed that it was very effective to plant artificially halophytes or suitable species through soil test.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.38 no.4
• /
• pp.310-319
• /
• 2018

The southern type grasses announced for the test were the Bermudagrass cultivars (Giant, Cheyenne, Mohawk, Panchero Frio, Common and Tifton 85) and the Bahiagrass cultivars (TifQuik, Tifton 9), and the changes in the productivity and nutrient content were surveyed in Jeju area (450m altitude). The different cultivars were sowed by broadcasting or drill seeding method, and Tifton 85 was transplanted from sprigs. The fresh and dry matter yield showed varying significant differences for different cultivars (p<0.05). The fresh yields of Tifton 85, TifQuik and Tifton 9 were excellent, compared to the other cultivars, and for the dry matter yield, Tifton 85 and Tifton 9 were excellent when compared to the other cultivars. Crude protein content showed significant differences among different cultivars (p<0.05). Cheyenne, Mohawk, Panchero Frio, and Common showed differences in the crude protein content by sowing method and harvest time (p<0.05). The different cultivars showed differences in the crude fiber content (p<0.05), and Tifton 9 registered significantly high content and Mohawk and Tifton 85 showed significant crude fiber content by harvest time (p<0.05). According to these results, the southern type grass cultivars showed big differences in the regenerative capacity against damage from frost, productivity, and nutrient content, so they need to be chosen according to the purposes, and to increase their usage, their evaluation needs to be conducted at various altitudes.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.63 no.4
• /
• pp.282-293
• /
• 2018

The heading response of rice varieties is determined by the combined effects of their basic vegetative phase (BVP), photoperiod-sensitivity (PS), and thermo-sensitivity (TS). This study was performed to analyze the effect of differences among heading ecotypes of rice on their heading response in the field. To do this, we investigated the heading response of 15 varieties grown under different day-length and temperature conditions in a phytotron. The characteristics of heading ecotypes were compared to the heading responses in the field-grown rice varieties that were used in the phytotron experiments. The ranges of these characteristics across the 15 varieties were 18 - 35 days for BVP, 12 - 61 days for PS, and 12 - 35 days for TS. In comparisons of coupled varieties that differed only in a single trait among BVP, PS, and TS, the variety with the longer BVP and that with the higher PS had a longer period from sowing to heading (DTH), while the variety with the higher TS had a shorter DTH. The comparative magnitude of DTH in the coupled varieties followed the PS trait when BVP and PS were involved, the BVP trait when BVP and TS were involved, and the PS trait when PS and TS were involved in the heading response of field-grown rice. When comparing the coupled varieties with different traits of the three examined factors, the heading response was consistent with the PS trait. The DTH in all 15 varieties was significantly correlated with the PS, and the DTH in 9 selected varieties with a relatively small PS was correlated with BVP. The reduced DTH of rice in the July 10 seeding treatment compared to those in the June 25 and May 11 seeding treatments was positively associated with PS, but not with TS. We concluded that the heading response of rice varieties under natural conditions in Korea is mainly governed by the PS trait and is also greatly affected by the BVP trait when the PS is small.

• Korean Journal of Heritage: History & Science
• /
• v.45 no.2
• /
• pp.54-71
• /
• 2012

This paper investigates Buddhist sculptures of the Gulsan-sa School of Seon Buddhism, which was established by the priest Beomil(梵日) at Myeongju(溟州), present-day Gangneung(江陵) area, and prospered until the late Goryeo period. There are very few surviving Buddhist images at Gulsan2 temple-site showing the Buddhist art when Beomil or his disciples, Gaecheong(開淸) and Haengjeok(行寂), were active, except a set of huge stone pillars for temple-banners and a stone monk stupa. It is therefore necessary to focus on pieces of artworks in Gangneung and nearby areas to explore the characteristics of Buddhist art of Gulsan-sa from the late Silla to early Goryeo period. For example, the stone relief seated Buddha image, one of Four Buddhas of Four Directions, and a stone relief of standing Guardian King both from the stone pagoda at Mujin temple-site(無盡寺址) can be compared with stupa reliefs at the capital Gyeongju area in their high quality of carving. The stone octagonal base showing seven lions on each of seven sides at Boheon-sa(普賢寺) demonstrates that it was made as a part of an octagonal lotus pedestal for a Vairocana Buddha now lost. Since Boheon-sa was erected by Gaechung, a disciple of Beomil as a branch of Gulsan-sa, it is fair to assume that the Vairocana image at Boheon-sa might have been closely related to the Buddhist images at Gulsan-sa in its style and iconography. The stone seated Bodhisattva from Hansong temple-site(寒松寺址) displays a benign face, exquisite necklace, and exotic iconography in its hand gesture and high cylindrical crown. The stone seated Buddha at Cheonghak-sa(靑鶴寺), brought from a temple-site where fragments of roof-tiles with the inscription of Heukam-sa(黑岩寺) were discovered, displays the late Silla and early Goryeo period. Heukam-sa seems to have been related to Gulsan-sa or have been one of the branches of Gulsan-sa. Extant fragments of artworks at Myeongju implicate the high quality of Buddhist art of Gulsan-sa in its iconography and style as well as unique features of Gulsan-sa Seon School.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.5
• /
• pp.514-520
• /
• 1996

To clarify the proper nitrogen application level for rasing rice infant seedling under different nursery soil, Dongjinbyeo was raised at seedling box with different basal nitrogen level. The results are as follows. The higher the nitrogen level was, the lower emergence rate and the lower establishment rate. The establishment rate was less than 90%, when the nitrogen was more than 2g/box in hill soil and more than 1g/box in paddy soil. The more the nitrogen level was, the higher the seedling height in hill soil, but was higher in the order of N-2, 3, 1 and 0g /box. Leaf number wasn't significantly different between nusery soils and among nitrogen levels when seedling was raised more than 6 days. The endosperm survival rate was decreased as the increased nitrogen level, but wasn't different between the nursery soils. Amount of root was decreased as the increased nitrogen level in paddy soil, but was heavier in the order of N-1, 0, 2 and 3g /box in hill soil. Mat formation was better as the nitrogen level was decreased in all nursery soils. Considering the emergence rate, seedling charactors and mat formation, the proper nitrogen levels seemed to be 2g /box for hill soil and 1g /box for paddy soil.

• Korean Journal of Weed Science
• /
• v.12 no.3
• /
• pp.271-291
• /
• 1992

This study was conducted to survey the situation of direct rice seeding in Honam province in Korea to investigate problems and seek countermeasure of weed control in direct rice seeding. The total area of direct rice seeding in the south-western part of Korea (Chonbuk, Chonnam, and Chungnam) was 1650.8ha (732.1ha for direct seeding in dry field and 918.7ha for direct seeding in flooding field) in 1992. The followings are summary of the study. 1. In case of direct rice seeding in dry field, butachlor EC and G at 3 to 5 DAS was mostly selected by farmers to control weeds in dry field. Benthiocarb or chlornitrofen was also used in few cases. At 10 to 14 DAS just before rice emergence, tank misture of butachlor EC and paraquat was treated by some farmers. At 35 to 40 days, after flooding mixture of sulfonylurea derivatives was sequentially applied. Surviving weeds including barnyardgrass were finally controlled by mixture of bentazon+quinclorac WP foliage application. 2. In case of direct rice seeding in flooding field, weed control were mostly unsuccessful partially due to wrong selection of herbicide and missing the optimum application time. Three relatively successful weed control in the survey were summarized as follows. 1) Oxadiazon EC, butachlor or benthiocarb were treated just after puddling(5 to 7 days before seeding). then mixture of bentazone+quinclorac WP or sulfonylurea derivatives was sequently applied to control remaining weeds at 20 days after seeding. 2) Mixtures of bensulfuronmethyl+dimepiperate G, pyrazosulfuronethyl+molinate G, or bensulfuronmethyl+mefenacet+dymron G were applied at 11 days after puddling when barnyardgrass were at 2.0 leaf stage. Phytotoxicity was not found in case of mixture of bensulfuronmethyl+dimepiperate G but found in the other two cases but disappeared later. 3) Mixtures of bensulfuronmethyl+quinclorac G., pyrazosulfuronethyl+quinclorac G or betazone and quinclorac G were treated after 18 to 20 days after puddling when barnyardgrass was within 3.0 leaf stage. It showed good weed control in both annuals and perrenials without phytotoxicity. On the contrary, other sulfonylurea derivatives such as middle periodic herbicide showed poor weed control against barnyardgrass, so that sequential treatment of bentazone+quinclorac WP mixture was required. 3. Herbicidal characteristics and optimum application time of 45 rigistered herbicides in Korea were analyzed to discover new substitute for quinclorac mixture, that showed excellent weed control against barnyardgrass at its 3 leaf stage or older. The analysis revealed that 70% of herbicides were for preemergence and the others were post periodic herbicide. Most farmers favor to apply herbicide when rice seedlings completely rooted, at this time barnyardgrass are at 2.5-3.0 leaf stage. Therefore herbicide of which optimum application time had long is required. In this study. 6 middle periodic herbicides among sulfonylurea derivatives and 2 quinclorac mixture were selected and evaluated their weeding spectrums at different leaf stage of barnyardgrass in both soil application in flooding condition and foliage application in dry paddy field. The order of weeding spectrum in magnitude was as follows : bentazone+quinclorac WP> bentazone + quinclorac G>bensulfuronmethyl + quinclorac G>pyrazosulfuronethyl + quinclorac G> pyrazosulfuronethyl + Molinate G>bensulfuronmethyl + mefenacet + dymron G>bensulfuronmethyl + mefenacet G>bensulfuron methyl+benthiocarb G. The above results coincided with that of the survey. In conclusion, there is no proper substitute for quinclorac mixrure, which can control barnyardgrass at 3.0 leaf stage or even older. Therefore quinclorac should be supplied continuously to farmers in order to anchor direct rice seeding in Korea. Author suggested the followings to eastablish direct rice seeding technology effectively and quickly : 1) A tentatively named "The research committee for direct rice seeding" which was composed of farmers. researchers and goberment. should be eastablished to cooperate effectively. 2) Development of a pricise direct rice seeding machine for both dry and flooding paddy field. which is workable regardless of condition and varieties of seeds. 3) Study on protecting rice seed and seedling from sparrows. 4) Systematic studies of weed control techniques in direct rice seeding to standardize herbicide application. 5) Studies on farm-land reformation. techniques of precise land preparation. and direct rice seeding using an airplane.