• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
• /
• 2001.06a
• /
• pp.97-100
• /
• 2001

벼의 수량은 일차적으로 결정되는 단위면적당 영화수와 출수기 전후의 광합성량과 동화산물의 이삭으로의 전류에 의해 결정되는 등숙율에 의해 최종 결정된다. 또한, 단위면적당 영화수의 증가는 수량증대에 중요한 역할을 하며(Ying et al., 1998; Kropff, et al., 1994a), 단위면적 당 영화수는 벼 수량변이의 약 80% 이상을 설명할 수 있다고 하였다(Yoshida and Parao, 1976).(중략)

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.46 no.3
• /
• pp.170-175
• /
• 2001

This study was carried out to investigate the distribution and characteristics of off-type rice plant in farmer's paddy field. The ratio of the field contaminated by off-type rice was highest in the southwestern area, followed by the southeastern area, the central area in Korea. The occurrence density of off-type rice was higher in the southern area than the central area. The short-grain red rice was the most dominant off-type rice group, followed by extremely late and sterile rice group and long-grain red rice group in Korea. The long-grain red rice group was dominant in Jeonnam and Kyongnam, and the extremely late and sterile rice group was dominant in Jeonbuk, and the short-grain red rice group in the other provinces. The culm length of most off-type rice groups growing in the farmer's paddy fields was longer than the farmer's cultivars, and the long-grain red rice group and the short-grain red rice group were especially longer. The number of spikelets per panicle of the off-type rice groups were generally greater than the farmer's cultlvars, and in particular, the extremely late and sterile rice group and the long-grain normal rice group had more spikelet per panicle. Most of the off-type rice groups were extremely sterile.

• The Korean Journal of Pesticide Science
• /
• v.19 no.4
• /
• pp.394-398
• /
• 2015

This research was performed to establish economic threshold (ET) for rice sheath blight disease with the cultivar Odeabyeo. Total yield and yield components, such as the panicle number per hill, the spikelet per panicle, the percent ripened grain and the thousand grain weight were evaluated depending on the disease severity of sheath blight on rice, respectively. Significant negative correlation between the percent of diseased hill (PDH) and total yield was observed (r = -0.93). Moreover, negative correlation coefficients were found between PDH and spikelet per panicle, and percent ripened grain (r = -0.66 and -0.77, respectively). There were no correlations between PDH and the panical number per hill, and a thousand grain weight, respectively. In this study, economic threshold level on sheath blight disease on rice was established on 7.8% of PDH.

• Korean Journal of Plant Taxonomy
• /
• v.41 no.1
• /
• pp.81-86
• /
• 2011

Two unrecorded Poaceae species, Anthoxanthum glabrum and Saccharum arundinaceum, are herein newly reported from Korea. Anthoxanthum glabrum (Ae-Gi-Hyang-Mo) was found in Ansan-si, Gyeonggi-do, Sangju-si, Gyeongsangbuk-do and Hwasun-gun, Jeollanam-do. It is distinguished from A. nitens by the length of its spikelet, glume and lemma. Saccharum arundinaceum (Keun-Gae-Sa-Tang-Su-Su) was found in Mapo-gu, Gangnam-gu, Seoul, and Hwasun-gun, Jeollanam-do. It is distinguished from S. spontaneum by hair on the lower glume and according to the length of the hair on the callus of its spikelet. In this study, a description and illustrations of the species and photos of the habitat are provided.

• Korean Journal of Environmental Agriculture
• /
• v.28 no.1
• /
• pp.53-58
• /
• 2009

The propose of this study was to find out optimum conditions for no-tillage rice-winter cover crops cropping system. A field research was conducted to evaluate productivity and quality of rice cultivars (Dongjinbyeo and Junambybyeo) in rice-winter cover cropping systems at Doo-ryangmyeon., Sacheon, Gyeongsangnam-do, Korea from January 2005 to October 2006. The experimental soil was Juggog series (fine silty, mesic family of Fluvaquentic Eutrndepts). The rice cultivars were experimented under some different high residue farming systems, i.e. no-tillage no treatment (NTNT), no-tillage amended with rice straw (NTRS), no-tillage amended with rye (NTR), no-tillage amended with Chinese milkvetch (NTCMV), tillage no treatment (TNT), and conventional cropping system (Control). The miss-planted rate was 8.8% in 2005 and range of 10.8% to 13.3% in 2006 at NTR, and the other treatments were carried out at miss-planted rate ranging from 1.2% to 5.0%. Tiller numbers of Junambyeo, and Dongjinbyeo in both of years were the highest in Control, and decreased nearly in NTCMV, NTR, NTRS, NTNT, and TNT in that order. The lowest grain yield was observed in TNT both cultivars due to the lower tiller numbers per area, and spikelet numbers per panicle. Also, no-tillage treatments were lower grain yield than control. On the other hand, 1,000-grain weight was lowest in control due to higher tiller numbers per area, and spikelet numbers per panicle. Ripened grain ratio was a similar aspect in all treatments. The palatability score of milled rice was lowest in control while protein content of milled rice was highest in control. The NTCMV was considered an effective sustainable farming practice for rice yield and quality.

• Korean Journal of Weed Science
• /
• v.10 no.3
• /
• pp.171-178
• /
• 1990

This study was conducted to determine which of the different agronomic traits of rice (Oryza saliva L.) has greater weight in predicting thiobencarb (S-[(4-chlorophenyl) methyl]diethylcarbamothioate) tolerance. Differences in plant height, tiller number, culm length, panicle number, and spikelet number per panicle between tolerant and susceptible cultivars were greater at the higher herbicide rate. However, days to heading and percent filled spikelets were not affected by herbicide rate. At the higher thiobencarb rate, the coefficients for all characters except plant height, tiller number, and percent filled spikelets were significant. Spikelet number per panicle and panicle number which had positive significant coefficients at both concentrations are the most useful indicators of total filled spikelets.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.44 no.2
• /
• pp.106-111
• /
• 1999

To investigate the effects of planting density and nitrogen level on growth and yield potential of newly bred heavy panicle japonica rice with large grain (Iksan 435 and Iksan 438) or many spikelets per panicle(HR14022-21-8-4 and HR14022-21-8-6), four heavy panicle type rices and two many panicle type rices(Dongjinbyeo and Donganbyeo) as the checks were planted under standard planting density (30$\times$15 cm) and dense planting density (15$\times$15 cm) with two nitrogen levels of standard nitrogen level(110 kg h $a^{-1}$) and heavy nitrogen level(165 kg h $a^{-1}$). Effective tiller rate decreased in dense planting or heavy nitrogen, when compared to standard nitrogen and planting, while leaf area index and to dry weight increased in dense planting or heavy nitrogen. Tiller numbers and panicle numbers were more increased by dense planting than heavy nitrogen, whereas spikelet numbers were more increased by heavy nitrogen than dense planting. Ripened grain ratio was slightly lower only in dense planting. 1,000 grain weight in brown rice was not significantly different in dense planting or heavy nitrogen. Milled rice yield was highest in heavy nitrogen with standard planting for heavy panicle type rice, while yield for many panicle type rice was highest in heavy nitrogen with dense planting, suggesting that many panicle type rice possesses higher adapt-ability for dense planting than heavy panicle type rice. Path coefficient analysis revealed that top dry weight, spikelet number and grain weight were the greatest positive contributors to yield, whereas tiller number was negative to yield.d.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.44 no.2
• /
• pp.122-128
• /
• 1999

Three rice cultivars, Namweonbyeo (early maturing), Hwaseongbyeo (medium maturing) and Dongjinbyeo (medium-late maturing) were trans-planted with 3 different seedling ages to investigate their growth habits and to improve the cultural method in paddy fields in the southern plain area of the Honam region in 1993. The 10-day old seedlings had more vigorous elongation of plant height and higher tillering ability but lower effective tiller rate, when compared with 35-day or 40-day old seedlings. Leaf area index and top dry weight were lower in 10-day old seedlings up to 40 days after transplanting but thereafter, were not different among seedlings ages. CGR was later in 10-day old seedlings, up to 30 days after transplanting, but in 30 to 40 days after transplanting, it was reversed. RGR was the highest in infant seedlings to 40 days after trans-planting, while in 50 days after transplanting, it was reversed. Panicle number and spikelet number per square meter were the highest in 40-day old seedlings, next highest in 35-day old seedlings and the lowest and in adult seedlings up to 40 days after transplanting, while spikelet number per panicle was vice versa. Milled rice yield did not vary significantly by seedling ages, but among the varieties, it was less in Hwaseongbyeo compared with Naweonbyeo and Dongjnbyeo.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.47 no.4
• /
• pp.273-278
• /
• 2002

An efficient low-input system (LIS) for fertiliser use in rice cultivation is necessary to reduce fossil energy use and pollution. Japanese people like Japonica rice, especially cv. Koshihikari. However, it has very low lodging resistance in Japanese weather condition. Our objective was to develop a LIS with the minimum sacrifice of grain yield in rice. Koshihikari was grown using conventional fertilization as a control (CON) with 4 g N $m^{-2}$., 8g $P_2$ $O_{5}$ $m^{-2}$ and 8 g $K_2$O $m^{-2}$ as a basal fertilizer dressing. It was compared with a low fertilizer treatment (LF) with only 4 g $P_2$ $O_{5}$ $m^{-2}$ as a basal dressing in the first year and no basal phosphorus fertilizer in the second year. Chopped rice straw was incorporated into the soil before the cropping season in both years. Fertilizer of 4 g N $m^{-2}$ was top-dressed at 15 days before heading in CON plots and 30 days before heading in LF plots in both years. Lodging was significantly less in LF than in CON plots, however, no rice straw effect was found in low fertilized condition. Grain yields in LF plots were reduced by 15-16% below those of CON plots. Lower yields in LF plots were associated with a reduced number of spikelets per unit area. However, big spikelet size was acquired in LF by 10 days earlier N top dressing than CON plots. A close relationship was found between spikelet numbers and N content of the plant at heading, and between grain yield or shoot dry weight and N content of the plant at maturity. Regardless of the fertilizer application methods, N use efficiency for the number of spikelets, final total dry matter and grain yield was essentially identical among fertilizer treatments. The reduced growth and yield in the LF plots resulted from low absorption of nitrogen. Conclusively, LIS can drastically reduce chemical fertilizer use and facilitate harvest operations by reducing lodging with some yield reduction..

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.44 no.1
• /
• pp.59-63
• /
• 1999

Yield and growth characteristics were compared for five rice cultivars; a new Tongil-type, so called "super-rice", Dasanbyeo, an old Tongil-type Milyang 23, two japonicas Dongjinbyeo and Ilpumbyeo, and a new plant type (NPT)line IR65600-27-1-2. The objective of this stusy was to clarify the high yielding capacity of Dasanbyeo in terms of growth characteristics. The average grain yield (9 t/ha) of Dasanbyeo was higher than that of Milyang 23 by ca. 9% that of japonicas by 20 to 30%, and that of NPT line by ca. 100%. The higher grain yield of Dasanbyeo was attributable not only to the greater dry matter production but also to the higher harvest index (HI). Dasanbyeo showed the greatest dry matter at harvest owing not only to the rapid leaf expan-sion at early growth stage and the resulting high LAI through the entire growth stage but also to the high NAR despite the high LAI. The rapid leaf expansion of Dasanbyeo at early growth stage seemed to be related in part to the profuse tillering capacity. HI was 0.53 in Dasanbyeo, 0,51 in Milyang 23, 0.41 in japonicas, and 0.35 in NPT line. Dasanbyeo was indebted for its higher HI to the relatively high grain filling ratio in spite of a much greater sink size than the other cultivars. Dasan had a greater source to sink ratio during grain ripening as measured by LAD/spikelet and dry matter production/spikelet which showed positove correlations with the grain ripening ratio. New plant type (NPT) line showed the lowest grain yield owing to the small sink size and the low grain filling ratio which seemed to have resulted from the abundant occurrence of weak-strength spikelets. The weak sink strength, in turn, seemed to have suppressed photosynthesis during the grain ripening stage.