• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.211-211
• /
• 2017

This experiments were conducted to investigate seed germination to evaluate the influence of anaerobic digestate on seed germination of perennial ryegrass seeds. The study conducted a germination experiment in petri-dishes, using perennial ryegrass seeds. The treatments were compared: non-treated control treated with distilled water, different concentration of anaerobic digestate. The germination percentage of perennial ryegrass seeds was highest in the fermented anaerobic digestate treatment. Root length of perennial ryegrass seeds was long by 4~5cm in the fermented anaerobic digestate with unfermented anaerobic digestate. In the relative root length ratio was by 30% higher in the in the fermented anaerobic digestate with unfermented anaerobic digestate. The germination index of perennial ryegrass seeds was high by 113% in the fermented anaerobic digestate compared to no treatment. The fermented anaerobic digestate have shown stimulatory effects in germination and development of root. Use of fermented anaerobic digestate can be recommended to farmers as a ecofriendly practice for better germination and growth.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.71-71
• /
• 2017

Stable stand establishment is pre-requisite in direct rice seeding system for obtaining optimal yield of rice crop in rain-fed and waterlogged areas. Anaerobic condition on waterlogged soil causes low germination which significantly reduces crop yield. Due to low availability of tolerant genetic material for anaerobic germination, there is urgent need to evaluate rice germplasm for better germinability under anaerobic conditions. Seeds of the 185 rice accessions were evaluated for germination vigor and coleoptile length under anaerobic conditions. The variation among germplasm was tested for significance using analysis of variance and various multivariate components. Significant level of variation was observed among all accessions for germination vigor and coleoptiles length. Although highest mean values for coleoptiles length (2.1cm) and germination rate (60%) were observed in japonica accessions but maximum coleoptile length (4.68cm) and germination rate (96%) was found in indica genotype CO18. A highly significant and positive correlation was also observed between germination vigor and coleoptiles length, which signify the importance of elongated coleoptile under anaerobic conditions. The PCA analysis illustrated that 97.24% variation was accounted by PC1 while PC2 and PC3 explained 2.54% and 0.24% variation for germination vigor and coleoptile length. PCA scattered plot divided the accessions in four various groups. All AG tolerant accessions were included in group I. Likewise in the case of cluster analysis, two major clades (I and II) were formed. All accessions showing >40% germination rate were included in clade I, whereas all other accessions with <40% germination rate were grouped in clade II. Further more highly tolerant accessions (>80% germination) were grouped in sub-cluster IA.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.192-192
• /
• 2017

Direct-seeding cultivation of rice is increasing in Asia instead of transplanting system, because of its lower cost and operational simplicity. Low-temperature germinability (LTG) and anaerobic germinability (AG) are important characters for breeding of varieties for wide-spread adoption of direct-seeding cultivation in rice. This study was performed to characterize LTG and AG of seven rice varieties and identify varieties with strong germinability on both low-temperature and anaerobic conditions. The mean germination rate and germination vigor of seven varieties were 51.7% and 6.0 under low-temperature condition, respectively. Among these varieties, Cheongcheongjinmi and Hwanggeumnodeul had the highest germination rate of 80%, indicating that Cheongcheongjinmi and Hwanggeumnodeul have a good LTG. In anaerobic conditions, the germination rate and coleoptile length for all varieties were 47.6% and 3.2 cm, respectively. Of them, the highest germination rate and coleoptile length were observed in Subo and Hopum, respectively, suggesting that these two varieties are tolerant to anaerobic during germination stage. Molecular characterization by SDS-PAGE revealed that the protein patterns differed at 50 kDa, 40 kDa, and 22 kDa between low-temperature and anaerobic conditions. Varieties identified as good LTG or AG in this study may be used for developing new direct-seeding rice cultivars through pyramiding these traits in the breeding program.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.38 no.1
• /
• pp.7-15
• /
• 2018

This experiments were conducted to evaluate the influence of Chlorella culture solution using anaerobic digestate as medium on seed germination of perennial ryegrass seeds. Four treatments were compared: control with distilled water, anaerobic digestate, Chlorella culture solution and Chlorella culture filtrate. The germination percentage of perennial ryegrass seeds was highest in the Chlorella culture solution treatment. Days required for 50, 70% seed germination were faster at 1.7 day in Chlorella culture solution compared to control. Root length of perennial ryegrass seeds was longer by 1~2cm in the Chlorella culture solution compared with control. The relative root length was by 40% longer in the Chlorella culture solution treatment compared to control. The germination index (GI) of perennial ryegrass seeds was higher by 180~202% in the Chlorella culture solution treatment compared to control. The decay rate was low as 50.0% in Chlorella culture solution, but decay rate of perennial ryegrass seeds showed 86.7~83.3% in control plot and in anaerobic digestate, respectively. Chlorella culture solution have shown stimulatory effects in germination and development of root. Overall, Chlorella culture solution could be useful to apply for promotion of germination and root elongation of seeds.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.64 no.4
• /
• pp.287-298
• /
• 2019

The aim of the present study was to compare the germination and seedling characteristics of rice varieties grown under various flooding conditions and different temperature and oxygen levels and to identify germplasm suitable for wet direct seeding. Three anaerobic germination tolerant (AGT) genotypes (PBR, WD3, KHO) and eleven Korean rice varieties (KVs) adapted for direct seeding were evaluated for seedling performance under different temperatures (15, 18, 21, and 24℃ ) and oxygen levels (Low, Normal, High). Compared with the KVs, the AGT genotypes (especially KHO and PBR) exhibited relatively high germination and survival rates and coleoptile and radical growth rates under low temperature and low oxygen conditions, thereby indicating their suitability for wet direct seeding. Among the KVs, 'Dongan,' 'Jungan,' and 'Cheongdam' rice exhibited the highest survival rates under low temperature and low oxygen conditions. Three-way ANOVA indicated that temperature had the greater effects on seedling characteristics (43.2-78.0%) than either oxygen level (15.4-37.5%) or genotype (2.0-29.8%) did. Therefore, in direct seeding cultivation, temperature was the most important environmental factor for seedling establishment.

• Korean Journal of Weed Science
• /
• v.8 no.1
• /
• pp.15-22
• /
• 1988

In this experiment, interactions between light and other factors such as chilling, alternating temperature, moisture, content, oxygen, and seed coat which affect germination of Oenothera lamarckiana Ser. seed were investigated to study the physiological effects of light on the germination. Light induced the initial stage of seed germination before radical protrusion by affecting embryo rather than seed coat even under anaerobic condition or low water potential (-18 bars). This light effect on germinability of seed was suppressed by blue light irradiation and the effect was increased with increment of blue light intensity and irradiation time. However, the blue light effect was reversible. Chilling, alternating temperature, softening of seed coat and light showed promotive interaction in the induction of seed germination. Irradiation of filtered light (monochrome), however, reduced chilling effect on germination. Hydrogen-ion concentration and gibberellic acid treatment had no effect on light or dark germination.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.36 no.4
• /
• pp.393-401
• /
• 2016

Anaerobic digestion is a collection of naturally occurring processes that convert organic matter and liquid residue, so-called digestate. The use of digestate biofertilizers is one of the important components of integrated nutrient management, as they are renewable sources of plant nutrients for sustainable agriculture. Seeds of Italian ryegrass (Lolium multiflorum L.) were germinated in different concentration of Chlorella in order to investigate it's the effect of Chlorella on growth parameters, seed germination and early growth. The experiment using plug tray was conducted at the green house placed in the Sangji University. The experiment consisted of nine treatments including different concentrations of Chlorella sp. culture solution and non-treated control. The germination percentage at the treatment with 25% Chlorella sp. culture solution was greater than that of control. The 50% concentration of Chlorella sp. culture solution was found to promote a better seedling growth in terms of shoot length, fresh weight and dry weight compared to the anaerobic digestate. Results showed that the best concentration of Chlorella culture solution was achieved by the 50% concentration of Chlorella culture solution treatment. As a conclusion, the application of Chlorella culture solution was found to be able to promote the germination and shoots growth of Italian ryegrass.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.65 no.4
• /
• pp.508-517
• /
• 2020

This study aimed to determine the minimum period of aeration treatment of co-digestate to develop it as liquid fertilizer and the chemical changes that occur in the aerobic liquefying process. The co-digestates were divided into three types depending on their additives: swine slurry anaerobic digestate (SS AD), swine slurry 70% + cow slurry 30% anaerobic digestate (SS + CS AD), and swine slurry 70% + apple pomace 30% anaerobic digestate (SS + AP AD). The pH of all co-digestates increased rapidly after 3 days of aerobic treatment, but had slightly decreased in SS AD after 9 days and in SS + CS AD and SS + AP AD after 15 days. All co-digestates showed a strongly reduced pH between 27 and 36 days of aeration treatment. SS AD had lower pH value, dissolved oxygen (DO), NH₄-N, and NO₃-N content under aerobic conditions than other co-digestates. To assess the fully decomposed liquid fertilizer, a germination test was performed on the undiluted and diluted co-digestate using the liquid fertilizer germination index (LFGI) method. The relative germination ratio, relative root elongation, and germination index of SS AD were higher than those of the others. When the LFGI method was used for the germination test, all co-digestates showed an appropriate germination index of 70 after 60 days of aeration treatment. Thus, we suggest that the minimum period of aeration treatment for co-digestates might be 60 days to develop the fully decomposed liquid fertilizer.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.65 no.3
• /
• pp.161-171
• /
• 2020

Direct seeding is one of the rice seedling establishment methods that is increasingly being practiced by farmers to save labor and reduce costs. However, this method often causes poor germination under flooding conditions after sowing. In this study, we developed japonica elite lines with quantitative trait loci (QTL) associated with anaerobic germination (AG) tolerance to overcome poor germination and seedling establishment in wet direct seeding. The QTL introgression lines were developed from a cross between weedy photoblastic rice as the AG donor and the Nampyeong variety via phenotypic and genotypic selection. Compared to Nampyeong, the survival rates of the selected lines were improved by approximately 50% and 240% under field and greenhouse conditions, respectively. To improve selection efficiency by marker assisted selection, the QTL markers associated with AG tolerance were converted to cleaved amplified polymorphic sequence markers designed based on next-generation sequence analysis. These lines retained similar agronomic traits and yield potential to the parent, Nampyeong. Among these lines, we selected the most promising line, which exhibited high survival rate and good agricultural traits under flooding conditions and named the line as Jeonju643. This line will contribute to breeding programs aiming to develop rice cultivars adapted to wet direct seeding. This study demonstrates the successful application of marker-assisted selection to targeted introgression of anaerobic genes into a premium quality japonica rice variety.

• 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.