• Korean Journal of Plant Resources
• /
• v.31 no.5
• /
• pp.522-530
• /
• 2018

Brachypodium distachyon has been developed as a monocot model plant for temperate grasses and bioenergy crops. Although B. distachyon research is moving forward rapidly, the study of photoresponses has not been explored. To extend our knowledge of responses to light in monocots, we performed photoresponse analysis of B. distachyon using two inbred lines, Bd21 and Bd21-3. In this study, we first compared growing phenotypes between the two lines and investigated coleoptile and primary leaf growths under dark, far-red, red, and white light conditions. The results showed that the growth of the two lines were similar until tillering stage, but other developmental stages from heading to senescence were much delayed in Bd21-3, which resulted in increased height and tiller numbers. Under different light conditions, primary leaf lengths were kept increasing during the growth period, whereas the coleoptile extension was inhibited 4 to 7 days after growth depending on the light conditions applied. These results suggest that the responses to light in B. distachyon can be examined by measuring coleoptile lengths approximately 7 days after seedling growth. Moreover, we selected light-responsive genes known in Arabidopsis thaliana, such as chlorophyll A/B binding protein (CAB), light-harvesting chlorophyll binding protein (Lhcb) and chalcone synthase (CHS), and confirmed their light-induced gene expression in B. distachyon. Therefore, the present study suggests that the inhibition of coleoptile growth can be used as the parameter to analyze photoresponses in the monocot model plant, and also provide the reference genes whose expression is induced by far-red and red light treatment.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.49 no.5
• /
• pp.363-367
• /
• 2004

The deep irrigation of rice plants brings about some beneficial effects such as reduced tiller production which results in the formation of bigger panicles, prevention of chilling injury, reduced weed growth, etc. The present study was carried out to examine the involvement of ethylene in the suppression of tiller production due to deep water irrigation in rice (cv. Dongjinbyeo). The ethylene production was induced in leaf sheath within 24 hours after the deep water irrigation and has increased even until 30 days after the treatment, recording 4.5-fold increase as compared to the shallow-irrigated rice plants. In the deep water irrigated rice plants, ethylene was accumulated to a high concentration in the air space of submerged leaf sheath as the irrigated water deterred the diffusion of ethylene out of the leaf sheath and ethylene biosynthesis was accelerated by the deep irrigation as well. The ethylene concentration recorded 35-fold increase in the deep-irrigated rice plants for 35 days. The tiller production was reduced significantly by the deep irrigation with water, the tiller bud, especially tertiary tiller bud differentiation being suppressed by the deepwater irrigation treatment, whereas the rice plants deep-irrigated with solutions containing $10^{-5}$ M or $10^{-6}$ M silver thiosulfate (STS), an action inhibitor of ethylene, showed the same or even higher production of tillers than those irrigated shallowly with water. This implies that the ethylene is closely linked with the suppression of tiller production due to deep water irrigation. In conclusion, ethylene, which was induced by hypoxic stress and accumulated in the leaf sheath due to submergence, played a key role in suppressing the tiller production of the deepwater irrigated rice.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.25 no.4
• /
• pp.28-37
• /
• 1980

New malting barley variety "Sacheon #6" is an early maturing, medium height, lodging resistance, high tillering, good quality and high yielding. This variety was developed from the cross Harupin-Nizo x Hokudai #2 made in 1970 at Sacheon Malting Barley Experiment Station, Doo San Farms Co., This variety was determined to recommend to the all malting barley production areas in southern part of Korea from 1979.from 1979.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.32 no.1
• /
• pp.48-54
• /
• 1987

To search for the optimal nitrogen application method for the machine transplanting to Dongjinbyeo, compared to conventional method, in the various methods of nitrogen split application at different growth stages of rice plant. This experiment was performed at Honam Crop Experiment Station, in 1985 year. The results were as followed; the nitrogen contents of leaf blade was the highest at maximum tillering stage under the conventional method and reduction division stage under the nitrogen top-dressing at panicle initiation and 5 times split application of nitrogen for the whole rice growth stages. CGR, RGR and NAR after heading was highest under 5 times split application of nitrogen for the whole rice growth stages. Relationships between CGR and NAR, NAR and RGR, CGR and RGR showed the positive correlation significantly at each rice growth stage, respectively, and showed more high correlation according to further rice growth stages. The degree of contribution of CGR to rice grain yield was the highest at 20 days after heading. Rice grail: yield was higher under top-dressing of nitrogen at panicle initiation and basal application (30%) + 4 times equal dispensing top-dressing after basal application of nitrogen than conventional method.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.35 no.2
• /
• pp.132-136
• /
• 1990

This experiment was conducted to study the multiplication and spread of bacterial population in water exuded through the hydathode of infected leaf of Xanthomonas campestris pv. oryzae in resistant and susceptible rice cultivars to bacterial leaf blight. The results obtained are summarized as follows. The bacterial multiplication in resistant cultivars was almost constant from three days to twelve days after inoculation with population of 10$^3$-10$^4$cfu/$\textrm{cm}^2$, but the multiplication was increased as days after inoculation extended in susceptible cultivars. The speed of bacterial multiplication and the number of bacteria spread above and below the inoculated position were closely related with the resistance of rice cultivars to bacterial leaf blight. The bacterial multiplication and spread were observed throughout the all growing stages including seedling, maximum tillering and flag leaf stages. The bacterial populations in water exuded through the hydathode were dependent on the multiplication and spread, and the populations were also closely related with the resistance of rice cultivars.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.50-50
• /
• 2017

Swampland is a potential alternative land to be used in various agricultural production activities in Indonesia, because Indonesia have 33.41 million hectares of swamp land that consists of 13.28 million hectares nontidal swamp and million hectares 20.13 tidal swamp. In the province of South Sumatra, because of unpredictable water level in the field before planting, farmers have been doing agronomic adaptation method through the delay time of transplanting and forced to apply more than one the nursery practice with the combination of a floating nursery method and a dry-bed nursery method. This study was aimed to (1) evaluate the seedling growth and tillering pattern of several popular Indonesian rice varieties, and (2) look for alternative technologies to get a better rice seedlings under two nursery methods in the nontidal swamp land. In the first experiment, the seedling growth characteristics of five rice varieties (Ciherang, Inpara 5, Inpara 9, Inpari 29, and Inpari 30) was evaluated by two methods of nursery, i.e. floating nursery and dry-bed nursery. In the second experiment, rice variety of Inpari 30 was treated with Zn seed priming and foliar fertilizer of 2,300 ppm N at the nursery stage. Those treatments were combined with the time of seedling under floating and dry-bed nursery. The results of the first experiment showed that of the five varieties tested, dry-bed nursery method showed better seedling growth than floating nursery. This was indicated by high leaf number, tiller number, tillers pattern, shoot-root ratio and relative growth rate. Ciherang and Inpari 30 showed high tiller number, and they had produced tertiary tiller in the sixth week of observation. Moreover, shorter period of floating and dry-bed nursery in combination with the treatment of Zn seed priming and spraying seedling with foliar fertilizer N could improve the growth of seedlings.

• 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.19
• /
• pp.100-131
• /
• 1975

To obtain basic information on the improvement of naked barley production. and to clarify the relation-ships between yield or yield components and some meteorogical factors for yield prediction were the objectives of this study. The basic data used in this study were obtained from the experiments carried out for 16 years from 1958 to 1974 at the Chon-nam Provincial Office of Rural development. The simple correlation coefficients and multiple regression coefficients among the yield or yield components and meteorogical factors were calculated for the study. Days to emergence ranged from 8 to 26 days were reduced under conditions of mean minimum air temperature were high. The early emergence contributed to increasing plant height and number of tillers as well as to earlier maximum tillering and heading date. The plant height before wintering showed positive correlations with the hours of sunshine. On the other hand, plant height measured on march 1st and March 20th showed positive correlation with the amount of precipitation and negative correlation with the hours of sunshine during the wintering or regrowth stage. Kernel weights were affected by the hours of sunshine and rainfall after heading, and kernel weights were less variable when the hours of sunshine were relatively long and rainfalls in May were around 80 to 10mm. It seemed that grain yields were mostly affected by the climatic condition in March. showing the negative correlation between yield and mean air temperature, minimum air temperature during the period. In the other hand, the yield was shown to have positive correlation with hours of sunshine. Some yield prediction equations were obtained from the data of mean air temperature, mean minimum temperature and accumulated air temperature in March. Yield prediction was also possible by using multiple regression equations, which were derived from yield data and the number of spikes and plant height as observed at May 20th.

• 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.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.43 no.1
• /
• pp.49-53
• /
• 1998

Direct-seeding has major advantages such as labor and cost saving by eliminating preparation of seed bed and transplanting. But, it required increased input of fertilizers and pesticides because of the extended paddy period. Direct seeding in wet paddy (DSWP) gives faster growth and more uniform seedling emergence than direct-seeding in dry paddy. This research had an objective to develop an efficient N management practices for DSWP with split application of N fertilizer. A paddy field experiment was conducted to evaluate effects of starter N and N-topdressing which was delayed N application until 5-leaf stage, with comparison to transplanting (TP). Total amount of N application were two levels; 110kg and 77kg/ha. The N applications were split four times during rice growth stages; starter, topdressing at 5-leaf stage, top dressing at tillering stage, and topdressing at panicle initiation stage. DSWP had more tillers/$m^2$ than TP, but with the delayed heading. The DSWP plots which received N-topdressing at 5-leaf stage without starter N had higher leaf area index (LAI) and leaf greenness than the TP plot. Also, these DSWP plots had high leaf-N concentration at the heading stage, as calculated from leaf chlorophyll meter readings. Rice yield in DSWP with N-topdressing at 5-leaf stage was significantly higher than that in TP and in DSWP with starter N. Energy and N use efficiency were improved in DSWP with N-topdressing at 5-leaf stage. But, there were no significant differences in grain yield between the two levels of total amounts of N applications, 77kg and 110kg/ha. We concluded that starter N could not be used effectively by rice seedlings, but topdressing N at 5-leaf stage was an efficient N management for rice growth and yield in DSWP system.