• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.57 no.2
• /
• pp.166-170
• /
• 2012

This research was carried out to choose the suitable seedling type to transplanting in order to stabilize rice yield. The brief of this research to transplant the seedling divided into 10-day seedling, 20-day seedling, 30-day seedling, 33-day pot seedling in the field of Saemangeum Gyehwa, newly reclaimed land were following; Average salt content in 2 years was reduced from 0.16% to 0.04% after transplanting. Heading date of seedling type was Aug. 14 at 33-day pot seedling compared to 2 days at 30-day seedling, 3 days at 20-day seedling, 5 days late at 10-day seedling. Lodging index was highest at 30-day seedling, and also, field lodging was 50%. Ripening ratio and 1,000 grain weight were similar and panicle number was higher 20-day seedling > 10-day seedling > 33-day pot seedling > 30-day seedling. Rice yield was higher 10-day seedling = 20-day seedling > 33-day pot seedling > 30-day seedling. Head rice ratio was higher in 20-day seedling > 30-day seedling = 10-day seedling > 33-day pot seedling. Amylose content and protein content was not significantly different between seedling types. With this results, the suitable seedling types in newly reclaimed land are 10-day and 20-day seedling.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.21 no.2
• /
• pp.77-86
• /
• 2019

To determine none top soil covering in rice seedling nursery method for the sparse machine transplanting, four different sowing methods were tested. Shoot and root length, fresh weight, leaf number and color using leaf color chart(LCC) and SPAD were collected as the data comparison of methods. The seedling height showed the highest growth according to the conventional (230g seed rate of pre-emerged seeds and top-soil covering) > high sowing density 1 (290g seed rate of pre-emerged seeds and top-soil covering) ≥ high sowing density 2(290g seed rate of pre-emerged seeds and none top-soil covering) > high sowing density 3(290g seed rate of iron-coated seeds and none top-soil covering). There was any statistical difference between groups in root length, leaf number, LCC, and SPAD values. Thus, a high sowing density of 290g for rice nursery seedling box was recommended to the sparse machine transplanting in rice cultivation with the none top-soil covering method, enabling convenient handling in transportation and machine transplanting work.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.327-327
• /
• 2017

The effect of different seedling ages and transplanting times on the growth and yield of Indica ${\times}$ Japonica rice for noodle processing was evaluated to develop a high yielding cultivation technology for increasing the competition against the imported foreign rice. Four seedling ages (10-, 20-, 30- and 33-day old) of two Indica ${\times}$ Japonica rice cultivars (cvs. Saemimyeon and Palbangmi) and three transplanting dates (May 20, May 30 and June 9) were used in the study. Our results showed that the growth and rice yield of the two cultivars were significantly affected by the different seedling ages and transplanting times. Dry matter production at the panicle heading of the two rice cultivars were generally higher in the 30-day old seedling than the other seedling age treatments and then gradually decreased as the transplanting time was delayed from May 20 to June 9. Similar high panicle number per square meter were recorded at the 30-day old seedling between May 20-May 30 transplanting times. In contrast, other yield parameters that includes spikelet number per panicle, 1,000-brown rice weight, and ripened grain ratio (except for the June 9 transplanting time of Palbangmi) were not significantly affected. The milled rice yield of Saemimyeon was higher than that of the Palbangmi regardless of seedling ages and it was also the highest at the 30-day old seedling with four seedling ages. The milled rice yield of Saemimyeon was only slightly decreased as the transplanting time was delayed from the May 20 to June 9 but Palbangmi had a significantly lower milled rice yield at June 9 transplanting due to the low ripened grain ratio. The result indicates that the most suitable seedling age for the cultivars tested was at 30-day old seedling for noodle processing rice and recommended transplanting times were between May 20 and May 30 for the high rice yield in the Yeongnam plain area.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.46 no.1
• /
• pp.47-52
• /
• 2001

In order to develop more stable seedling stand method in wet direct rice seeding culture, the effect of making the drainage ditches was studied in both methods of broadcast seeding on floody paddy surface and puddled-soil drill seeding. In a broadcast seeding on floody paddy surface, the ditching after seeding using a tractor or small ditch maker improved the seedling stand, and reduced the floating seedling and herbicide injury by accelerating the drainage. Suitable ditching time was at 2 days after seeding (DAS) for the tractor and at 3 DAS for the ditch maker. In the puddled-soil drill rice seeding culture, the ditching before seeding with a ditch maker at 3 days after draining effectively improved the seedling stand due to quick draining through well formed the seeding furrows. In the puddled-soil drill seeding, seedling stand number showed higher in both ditching plots synchronized with seeding compared with both only draining treatment at 1 DAS without ditching and the flooding plot condition for 6 DAS. And the suitable ditching depth was 6 cm, as considered the ditching status and drained status. These results suggest that the ditching in wet direct rice seeding is an resonable practice for improving the seedling stand through the accelerating drainage of field.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.48 no.2
• /
• pp.120-126
• /
• 2003

Four different rice varieties, Sindongjinbyeo, Dongjin #1, Saegyehwabyeo, and Iksan 467, were transplanted under three different nitrogen levels and two different seedling numbers per hill to obtain basic information on panicle traits under different cultural conditions and to propose the ideal panicle structure in Japonica rice. Sindongjinbyeo and Iksan 467 were characterized by more primary rachis branches (PRBs) per panicle and more grains on PRB than other cultivars. The two varieties also had fewer secondary rachis branches (SRBs) per PRB and fewer grains on SRB per PRB. These characteristics, consequently, resulted in higher ripened grain rate, contrary to that of Dongjin #1 and Saegyehwabyeo. In the correlation coefficient analysis, PRB number per panicle and grain number on PRB per panicle were positively correlated with ripened grain rate, while SRB number per panicle, number of grains on SRB per panicle, SRB number per PRB, number of grains on SRB per PRB and grain number per panicle were negatively correlated with ripened grain rate. Therefore, the number of grains on PRB per panicle, SRB number per PRB and the number of grains on SRB per PRB were the appropriate criteria for determining and achieving higher ripened grain rate in rice. High ripened grain rate over 90% was obtainable with over 12.5 PRBs per panicle and 63 grains on PRB per panicle, and with under 1.7 SRBs per PRB, 5 grains on SRB per PRB, 130 grains per panicle, and 14 panicles per hill. The study recommended that for over 90% high ripened grain rate, the critical limiting factors should be under 2 SRBs per PRB, 6 grains per PRB, and 130 grains per panicle, irrespective of the PRB number per panicle and the number of grains on PRB.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2003.10a
• /
• pp.38-42
• /
• 2003

This experiment was carried out the investigation of proper temperature of germination and growth responses of turf grass to different seedling ages. The results were as follows; 1. It was indicated that the proper temperature of germination was 30$^{\circ}C$ of day and 15$^{\circ}C$ of night, and day length was 14/10 hrs. 2. It was observed that 50 days of seedling was excellent with growth components such as number of tiller, length of tillering, number of node and internode length.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.10 no.3
• /
• pp.147-151
• /
• 1990

The purpose of this study is to clarify the relation of survival rates of seedling plants under grown orchardgrass populations and control by the difference cutting frequency. The orchardgrass populations investigated in this study have passed for 10 years after establishment. Cutting frequencies were 3, 4 and 5 times in a year. This experiment was conducted from April to October, 1989 at the experimental field of Institute of Agricultural Development, Yonsei University. The results are summarized as follows: 1. The survival rates of seedling plants decreased by the days after sowing. The final survival rates of seedling plants were 7.8%, 38.9% and 33.8% in 3, 4 and 5 cuttings, respectively. 2. Relative light intensity indicated highly possitive correlation with relative survival rates of seedling plants and negative correlation with plant length of orchardgrass populations in 4 and 5 cuttings. 3. The frequency distribution of survival seedling plants at 177 days after sowing were showed high values in seeding spots near the adjacent plants of 3 cutings, but in the middle of seeding spots between adjacent plants of 4 .and 5 cuttings, respectively. 4. The plant length of seedling became longer towards the seeding spots near the adjacent plants but the number of tillers increased slightly up to the middle of seeding spots between adjacent plants in all cutting frequencies.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.53 no.4
• /
• pp.434-439
• /
• 2008

The amount of salt to make seed sorting solution of the specific gravity of 1.13 was reconsidered and determined as 3.8 kg salt in 18 L water, which is lower amount than currently used. Five rice cultivars were examined. Percent germination and seedling emergence were not similar. Seedling emergence rate of Japonica varieties, Nampyungbyeo and Daerypbyeo-1 were 87% and 95% under specific gravity of 1.13, respectively. Seedling emergence rate of Tongil type variety, Dasanbyeo was as high as 67% in specific gravity of 1.06. Seedling emergence rate of waxy rice, Hwasunchalbyeo and Aranghangchalbyeo were examined. Seedling emergence rate was 94% in both cultivars in specific gravity of 1.04. Seedling emergence rate was same in specific gravity of 1.08 which is generally used for selecting seed currently. Early growth (plant height, leaf number, and dry weight) were not significantly different by specific gravity within species. In all cultivars except waxy rice, highest seedling emergence rate was observed in specific gravity of 1.13 which is currently used for selection and decreased as specific gravity is lowed. However, considering total amount of seeds in each group of specific gravity, amount of seed in lower specific gravity group is relatively small and total seedling emergence rate within variety dose not show big difference. However, if seeds with low speicific gravity are produced due to the bad grain filling condition and consequently total seed content of low specific gravity increases, results will be differnt. Reduction in total growth and yield could occur. It will be important to comply with the seed sorting criterion of 1.13 for Japonica, 1.06 for Tongil, and 1.04 for waxy rice variety to ensure the maximum rice growth and yield.

• Korean Journal of Agricultural Science
• /
• v.48 no.4
• /
• pp.945-956
• /
• 2021

The effective growth of pepper seedlings relies on the growing period and tray used, which both aim to minimize seedling damage during the transplantation process. Therefore, the objective of this study was to evaluate the effect of red and green pepper seedling growth in plug and cylindrical paper pot (CPP) trays with different growth periods of the seedlings. Two different seedling growth trays were used for the two varieties of pepper seedlings in the same growing media. The pepper seedling growth rates were investigated at 15, 30, and 45 days for each of variety. Important parameters, e.g., the plant height, fresh weight for the plant and root, number of leaves, leaf length and width, and leaf chlorophyll contents, were measured. During the experiment, the CPP tray maintained uniform seedling growth as compared to the plug tray. CPP trays ensured the height of the seedling, with these results 0.84 to 1.6 times higher than those of the plug tray for all conditions, indicating the good quality of the pepper seedlings. The shoot and root weights were found to be greater with more leaves in the CPP tray seedlings for 45 days compared to the seedlings grown in the plug tray, whereas the green pepper variety showed a greater leaf ratio than the red pepper seedlings. The analysis of pepper seedling growth presented in this study will guide the selection of suitable growth trays and seedling periods for farmers when they undertake automatic pepper transplantation in the field.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.1
• /
• pp.62-67
• /
• 1996

High density (HD) grains is associated with seedling vigor. Studies were conducted on the relationship of different grain densities and vascular bundle(VB) development and seedling growth. IR58 (indica type) and Unbong 7 (japonica type) were used in this experiment. HD grains had more and bigger VB in the leaf blade and sheath than poor density grain at seedling stage. IR58 had more large VB at the leaf compared with Unbong 7. Higher development of VB in seedling of HD grains can increase transport of assimilate and growth rate. Plant height, leaf number, root growth and dry weight increased with increasing grain density from poor to high. The total area of large VB in the leaf blade and sheath was highly correlated with the dry weight. Higher number and larger area of VB and dry weight can be obtained by using HD grains and these initial advantages can contribute to high yield potential.