• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.34 no.3
• /
• pp.310-323
• /
• 1989

This study was carried out to find out the difference of ripening and growth characteristics among the different florets in same panicle. There were 2 different transplanting date (May 25 and June 10) and 6 varieties were used. Physiological ripening period, ripening speed, 1000 grain weight, germination speed and grain quality were studied among the different florets (1, 5 and 8 days after heading) in same panicle. Physiological ripening period was long in late transplanting, late flowering floret, and late varieties by 3-9 days in Japonica. Ripening speed and 1000 grain weight were high in early transplanting and early flowering florets. There was positive correlation among the ripening speed, 1000 grain weight and a average temperature but negative correlation between the ripening and physiological ripening period. Germination speed was excellent in early flowering floret after heading. There was difference in amylose content within varieties and different flowering grains and there was significant correlation between grain quality and meteorological factors in some varieties.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.60 no.3
• /
• pp.282-292
• /
• 2015

Seeds of colored rice generally have high anthocyanin and flavonoid content but some cultivars have low seed germination rate. This defect poses unstable seedling establishment in nursery bed. The seed gravity variations of 10 colored rice varieties and its effect on germination, seed soaking duration and their optimum seeding rates for seedling raising in machine transplanting were investigated in the experiment. Based on seed gravity distribution of the 7 black- and 3 red-colored rice varieties at three levels of seed gravity (1.0<, 1.0~1.06, 1.06>), the black colored seeds such as Josaengheugchal and Sinmyungheugchal had high amount of specific gravity of below 1.0 ranging from 86~ 96%, while they had only 3~13% of seeds in specific gravity above 1.06. Sintoheugmi, Heugjinju, Heugnam, Heugkwang had various mass of seeds, showing 29~44% for specific gravity of below 1.0, 24~39% for 1.0~1.06 and 25~45% for above 1.06. On the other hand, the red colored rice such as Hongjinju, Jeogjinju and Geonkanghongmi had high percentage of specific gravity of above 1.06 with 84~86% while they had only 9~12% of specific gravity below 1.0 similar to Ilmibyeo of noncolored rice. The black colored seed generally showed low germination percentage, slow germination speed and long mean germination time, and low water absorption rate as compared with seed of the red colored rice which was similar to those of Ilmibyeo used as a control cultivar. The black colored seeds took 2~4 days longer seed soaking duration than the red colored rice before germination. This was related to high seed amount of specific gravity below 1.0 in black colored rices. The high amount of seed gravity above 1.06 in the colored rice seeds was positively correlated with percentage of germination, germination speed and mean germination time, ripened grain ratio and water absorption. Seed gravity distribution effect were less pronounced between back- and red- colored seeds in seedling emergence. The black colored rice has slightly lower normal seedling emergence rate than the red colored rice and Ilmibyeo in the seedbed soil due to high percentage of ungerminated seed. Normal seedling emergence rate of the black colored rice in the seedbed was 75.2~82.2% for 10-day old seedling and 85.3~ 90.9% for 30-day old seedling which was lower by 4.5~ 8.0% and 0~3.3%, respectively, than the red colored rice. Based on the normal seedling number per tray of Ilmibyeo for seeding rate of 10-day and 30-day old seedlings, the recommended seeding rate of black colored rice is 200~ 220g seeds for the 10-day old seedling and 110~130g for the 30-day old seedling in transplanting rice while the seeding rate of the red colored rice was 220g seeds for the 10-day old seedling and 130g for the 30-day old seedling.

• Korean Journal of Medicinal Crop Science
• /
• v.1 no.1
• /
• pp.3-9
• /
• 1993

This experiment was conducted to study germination characteristics and the decrease cause of germination percent in Angelica gigas Nakai seed. The emergence percent of winter sowing was higher than that of spring sowing as 66.6% and 41.1%, respectively, and the first emergence date was also earlier in winter sowing. The seed germination speed, percent and coefficent showed the highest value at $20^{\circ}C$ of incubation temperature, but lower value at $10^{\circ}C\;and\;30^{\circ}C$. The water uptake speed was increased along with increasing water temperature. The weight of imbibed seed at germination was 3.4times higher based on the weight of intact dry seed and 2.3times on removal of seed coat. In terms of length of seed was large, the germination percent was higher. The germination percent of brown colored seeds showed higher value than that of green colored seeds. The prolonged storage period decreased germination percent. When A.gigas seeds stored at room temperatue for 2years, the seeds were lost their viability. The biological inhibition effect of methanol, water and ether extract on the germination and growth of A.gigas and lettuce seed showed the highest value in the methanol extract, followed by water extract and the least in ether extract.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.42 no.1
• /
• pp.104-111
• /
• 1997

Since seeds of Italian ryegrass should be imported every year, it is necessary to investigate the prossible production of seeds in Italian ryegrass field after rice. Seven Italian ryegrass varieties were planted on October 8, 1986 at National Honam Crop Experiment Station at Iksan and clippings were made on April 10 and April 30 in 1987. Headings of K-11 and T.N.T were earlier than those of Tetrone and Bettina. For all varieties tested, heading date was delayed and 1,000 grain weight was decreased linearly as the clipping was made later. Length, width and thickness of a grain were reduced by clipping and later clipping, while tetraploid varieties produced larger grains than diploid varieties. The germination percentage and germination speed at $25^{\circ}C$ were higher than at 15$^{\circ}C$. The final germination percentage was lower at the later clippings and was higher at 15$^{\circ}C$, and earlier varieties showed higher germination percentage. Uniformity of germination was greater at $25^{\circ}C$ and was decreased as the clipping was made later, and the eariler varieties such as K-11 were germinated more uniformly. Average number of days to germination was longer at 15$^{\circ}C$ than at $25^{\circ}C$ and was longer at later clipping. The germination percentage was decreased linearly as the heading was delayed, while it increased linearly as the 1,000 grain weight was increased.

• Korean Journal of Plant Resources
• /
• v.20 no.4
• /
• pp.267-271
• /
• 2007

This study was carried out to examine optimal hot water treatment time in Albizzia julibrissin seeds. Germination and moisture absorption characteristics among intact seeds, immersed seeds for 24 hours in distilled water and hot water treated seeds were surveyed. As result, treated seeds showed a highly significant difference with intact and immersed seeds (p<0.0l). Especially, treated seed for 2.0 minutes represented the highest percent of germination (PG). But mean germination time (MGT) did not have significant difference between non-treatment and treatments (p=0.502). Germination speed and germination performance index showed similar tendency with PG. In percent of moisture absorption (PMA) and moisture absorption rate constant (MARC) treatments had higher values than non-treatment whereas 2.0 minutes treatment was lower than non-treatment in initial moisture absorption rate (IMAR). In relation between germination properties and moisture absorption characteristics, all properties except MGT among germination properties had high correlations with PMA and MARC ($r=0.854{\sim}0.931$,p<0.01) whereas IMAR didn't have correlation.

• Korean Journal of Plant Resources
• /
• v.22 no.1
• /
• pp.5-12
• /
• 2009

Seed priming is a useful technique for rapid and uniform seed germination as well as early seedling establishment. This experiment was conducted to find out the optimum condition for Sorbus alnifolia seed priming with four concentrations of four reagents in germination property and seedling growth performance. The results are summarized as follows: Percent germination (PG) varied 2.67% to 24.67%, and S. alnifolia seeds had the highest PG in the treatment that were primed in 100mM $KNO_3$ solution for 2 days. Mean germination time was the shortest in 200 mM $KNO_3$ solution for 2 days. Seed priming with $KNO_3$ solutions increased germination speed (GS) and germination performance index (GPI) compared with non-primed seeds. Especially seed primed with 100 mM $KNO_3$ solution for 2 days showed the highest GS and GPI. The highest relative growth rate (RGR) and seedling vigor index (SVI) was significantly (p<0.05) different from the control and other treatments, respectively. RGR of height (0.0071) and root collar diameter (0.0141) of seedling from primed seeds were the highest in 400 mM NaCl solution for 2 days. The highest SVI (5.43) was observed in the seedlings from seeds primed in 100 mM $KNO_3$ solution for 2 days. Consequently, the optimum reagent and concentration were $KNO_3$ and 100 mM for the effective germination and seedling growth in S. alnifolia

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.38 no.6
• /
• pp.507-512
• /
• 1993

Pre-sowing treatments of tobacco seeds (cv. NC82) were evaluated as a means of improving the speed of emergence, early seedling growth and uniformity of the seedlings. Seeds were treated through the use of polyethylene glycol 6000(PEG), solid matrix priming(SMP), chilling and dark-preincubati(DPI). Under the laboratory condition of 15$^{\circ}C$, all the treated seeds germinated more rapid and the time to 50% germination(T50) reduced than control. Among the treatments, SMP was the best to reduce the T50 for germination. All the treatments did not affect the final germination percentage, while the chilling showed of little benefit for germination and T50. Under the greenhouse condition, seedling from SMP emerged earlier and more uniformity and also greater mean fresh and dry weight showed than other treatments. The advantage of T50 from SMP was affected more in temperature than in water content of Agro-Lig during the treatment.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2018.10a
• /
• pp.87-87
• /
• 2018

This study was conducted to investigate the effects of osmotic priming, liquid smoke (LS), sonication and modified drum priming treatments to improve the germination speed and uniformity of pepper seeds for high quality export seeds. Seeds were treated in 0.5, 1.0, 5.0, 10% LS solution only or with 100mM $K_2SO_4$ solution for 6days at $15^{\circ}C$. Sonication treatment was performed for 5, 10, and 20 minutes at an intensity of 5.2, 10.4, 15.7, 21.0, 26.1kHz in water at $15^{\circ}C$. After sonication treatment, seeds were primed with water or 100mM $K_2SO_4$ for 4days. 40, 50 and 60% seed moisture content (SMC) of hydrated seeds were incubated for 84, 96 and 108h in a container with a relative humidity of 99% at 26rpm for a modified drum priming treatments. 0.5% LS treatment with water or 100mM $K_2SO_4$ priming showed significant effects with 71% GP (9.0days MGT) and 66% GP (7.4days MGT), respective, while untreated seeds resulted in only 61% GP and 10days MGT. The healthy seed % was increased by 24% by $K_2SO_4$ priming with LS treatment compared to untreated seeds. However, sonication treatment showed less germination or no difference compared to untreated seed, regardless of intensity and treatment time. The modified drum priming treatment (108h incubation after 50% SMC hydration) significantly improved the GP (on the $4^{th}$days after sowing), germination rate (GR), and MGT to 65%, $28%{\cdot}day^{-1}$, and 3.6days, whereas untreated seed resulted only 7% GP, $17%{\cdot}day^{-1}$ GR and 5.9days MGT. Thus, modified drum priming treatment effectively improved seed germination and is considered as an industrially promising treatment methods considering the shortening of the treatment period and environment-friendly aspects.

• Korean Journal of Breeding Science
• /
• v.42 no.5
• /
• pp.439-447
• /
• 2010

Riptortus clavatus, one of the many insects in major crops, damages pods and seeds, which reduces seed vigor and viability in soybeans. This study was conducted to examine the effect of diversely damaged seeds by R. clavatus on seed germination and seedling emergence and to determine the association of damaged seed with quality and yield of soybean sprouts. All seeds damaged by R. clavatus significantly (P<0.05) reduced seed vigor as measured by the rates of seed germination, germination speed, and seedling emergence. Mean seed germination rate of non-damaged seeds in sprout-soybean varieties was 97.8%, whereas the rates of seeds damaged at different levels, 31-50% and 51-80%, were 23.0 and 5.4%, respectively. The rates of seedling rot and abnormal, incomplete germination significantly (P<0.05) increased as the amount of seeds damaged by R. clavatus increased to 5, 10 and 15% against the total seeds for sprout production. Yield of soybean sprouts from seeds damaged at different levels decreased up to 13% as compared to that in normal seeds. In customer preferences on soybean sprout produce, 84% of customers participated in survey preferred to purchase sprouts from seeds with 5% of damaged seeds, but sprouts produced from seeds with 15% of damaged seeds were intended to purchase only by 22% of the customers. Areas of the seed damaged by R. clavatus were readily infected by pathogens as the seed germinated, resulted in deteriorated quality and reduced yield of sprout produce.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2022.10a
• /
• pp.132-132
• /
• 2022

The application of direct seeding cultivation reduces time, labor, and cost. However, this application often has poor seedling establishment and leads to lower yield as compared to transplanting system. The tolerance to anaerobic and low temperature germination is important to improve seedling establishment and the wide-spread application of direct seeding method. This study was carried out to evaluate the responses of three japonica cultivars to different temperatures (15℃, 18℃, 21℃, 24℃, and 27℃) and different flooding levels (1 cm, 4 cm, 7 cm, 10 cm) during germination and seedling development. The mean survival percentage significantly increased (P<0.05) when the flooding level decreased and when temperature increased. There were significant effects of the interaction between temperature and water depth on survival percentage and seedling height. When temperature decreased from 27℃ to 15℃, the germination duration significantly increased from 6.4 days to 16.3 days while the germination speed, survival percentage, and seedling height decreased from 5.3 seeds day^-1, 61.9% and 190.6 cm to 2.2 seeds day^-1, 33.2%, and 47 cm, respectively. The increase in temperature under submergence condition was associated with the increased expression of Amy3D and ALDH2a but the decreased expression of ADH1 and PDC1. The results of this research would be used for further studies and breeding programs to improve rice seedling establishment and the application of direct seeding cultivation.