Gi Jun Choi

Evaluation of Characteristics and Forage Production for Bermudagrass (Cynodon dactylon) and Bahiagrass (Paspalum notatum) in Jeju

This study was conducted to evaluate the characteristics and forage production of bermudagrass (Cynodon dactylon) and bahiagrass (Paspalum notatum) in Jeju. Bermudagrass cultivars evaluated were Common and Ecotype. Bahiagrass cultivars evaluated were Tifton 9 and Argentine. Two warm season grasses were established at the Subtropical Animal Experiment Station in spring 2007. Emergence of bremudagrass and bahiagrass was observed approximately 16 days and 28 days after seeding, respectively. The heading dates of bermudagrass and bahiagrass were on 26 May and in mid-July, respectively. Bermudagrass cultivars had higher dry matter (DM) than bahiagrass at first harvest. Dry matter yield of bahiagrass was higher than that of bermudagrass (p<0.05). Peak forage DM production of bermudagrass and bahiagrass cultivars was in June and July, respectively. The content of crude protein (CP) and total digestibility nutrient (TDN) of bermudagrass cultivars were higher than those of bahiagrass during the first harvest. Acid detergent fiber (ADF) and in vitro DM digestibility (IVDMD) were similar across the four cultivars. In Jeju, bermudagrass and bahiagrass provide a useful option for supplemental summer forage in most livestock forage systems.

Forage Productivity and Quality of Domestic Italian Ryegrass and Barley Varieties

Sung Seo, Won Ho Kim, Ki Yong Kim, Gi Jun Choi, Hee Chung Ji, Sang Hoon Lee,Ki Won Lee and Meing Jooung KimABSTRACTThis study was carried out to determine the forage production and quality of Italian ryegrass(IRG) and forage barley developed by Korea in Suwon, 2009’10. The nine treatments were two IRG varieties (Kowinearly with early maturity and Kowinmaster with medium maturity), five barley varieties(Youngyang, Wooho, Yuyeon, Dami and Youho), and two mixtures(Kowinearly+Yuyeon and Kowinmaster+Yuyeon). The heading dates of Kowinearly and Kowinmaster were 14 May and 18 May, respectively. The growth stage of barley investigated at 22 May were late milk in Youngyang and Wooho, early dough in Dami and early to medium dough in Yuyeon and Youho. Plant length of IRG in IRG+barley mixtures was 117118cm, which was longer than those of IRG monoculture of 98101cm, and no lodging was found in mixtures. The dry matter(DM) percentage at harvest was 20.725.4% in all treatments. The botanical composition of IRG in mixtures was 43.1%. The percentage of spike per barley plant was become high according to progressed maturity, as a 35.7%, 44.1%, 54.8% and 57.2% in late milk, dough, yellowish and full ripeness stage, respectively, and the spike percentages of Youngyang and Wooho were tends to high. The crude protein(CP) content of IRG as 9.010.0% was higher than that of barley(7.08.5%), and the contents of NDF and ADF of barley were lower than those of IRG, and in vitro DM digestibility were 64.4% in Kowinearly, 64.1% in Kowinmaster, 64.5% in mixture, and 60.2%(Youho) to 66.4%(Wooho) in barley. The yields of DM, CP and in vitro digestible DM were high in Kowinmaster+barley mixture as a 11,508kg, 1,046kg and 7,422kg per ha, respectively(p<0.05). However, no significant differences in forage yield were observed among cultivar of IRG, and barley, although Wooho was tends to high in digestibility and forage yield among five barley varieties. In conclusion, the mixture cultivation of IRG Kowinmaster+forage barley was recommended, because of preventing of IRG lodging, higher plant length of IRG, increasing of forage yield, and stable production. Selection of suitable winter forage species and variety for district, climate environment, and utilization type of farm was also important.(Key words: Forage production, Mixtures, Nutritive value, Cultivar, Winter forage)

Prediction of the Chemical Composition and Fermentation Parameters of Winter Rye Silages by Near Infrared Spectroscopy

ABSTRACT This study was carried out to explore the accuracy of near infrared spectroscopy (NIRS) for the prediction of chemical and fermentation parameters of whole crop winter rye silages. A representative population of 216 fresh winter rye silages was used as database for studying the possibilities of NIRS to predict chemical composition and fermentation parameters. Samples of silage were scanned at 1 nm intervals over the wavelength range 680~2,500 nm and the optical data recorded as log 1/Reflectance (log 1/R) and scanned in fresh condition. NIRS calibrations were developed by means of partial least-squares (PLS) regression. NIRS analysis of fresh winter rye silages provided accurate predictions of moisture, acid detergent fiber (ADF), neutral detergent fiber (NDF), crude protein (CP) and pH as well as lactic acid content with correlation coefficients of cross-validation (R 2 cv) of 0.96, 0.86, 0.79, 0.85, 0.82 and 0.78 respectively and standard error of cross-validation (SECV) of 1.89, 2.02, 2.79, 1.14, 1.47 and 0.46 % DM respectively. Results of this experiment showed the possibility of NIRS method to predict the chemical parameters of winter rye silages as routine analysis method in feeding value evaluation and for farmer advice.(

Optimum Harvest Stage of Italian Ryegrass 'Kowinearly' According to One and Two Harvests During Spring Season

Sung Seo*, Won Ho Kim, Meing Jooung Kim, Sang Hak Lee, Min Woong Jung, Ki Yong Kim, Hee Chung Ji,Hyung Soo Park, Jong Geun Kim and Gi Jun ChoiNational Institute of Animal Science, RDA, Cheonan 331-801, KoreaABSTRACTThis study was carried out to determine the optimum harvest stage of Italian ryegrass(Lolium multiflorum Lam., IRG) for maximum forage production during the spring season in Suwon, 2010. The variety of IRG was the early maturity type, ‘Kowinearly’, and six harvest stages(treatments) were first heading(T1), heading(T2), late heading to early bloom(T3), bloom to late bloom(T4), ripeness(T5), and late ripeness stage(T6). The dates of the first heading and heading of ‘Kowinearly’ were seen on 4 to 5 May, and 14 May, respectively. Plant length and dry matter(DM) percentage at first harvest were from 69cm and 14.8% at T1 stage to 103cm and 35.0% at T6 stage, respectively. The content of crude protein(CP) and in vitro DM digestibility(IVDMD) of T1, T2, T3, T4, T5 and T6 at first harvest were 15.6%, 10.6%, 10.1%, 8.1%, 7.3% and 5.4%, and 81.8%, 72.1%, 64.8%, 63.8%, 61.4% and 59.0%, respectively. The content of neural detergent fiber(NDF) and acid detergent fiber(ADF) were increased continuously with delayed harvest. A significantly higher yield of DM, CP and in vitro digestible DM(IVDDM) were observed for T3, and T4(p<0.05). DM yield of 3,526kg, 6,278kg, 7,842kg, 8,984kg, 8,346kg and 8,008kg/ha, CP yield of 549 kg, 665kg, 795kg, 725kg, 608kg and 430kg/ha, and IVDDM of 2,883kg. 4,526kg, 5,083kg, 5,728kg, 5,124kg and 4,722 kg/ha at first harvest were recorded in T1, T2, T3, T4, T5 and T6, respectively. Regrowth yield of DM, CP and IVDDM were shown to be higher at T1 and T2(p<0.05). However, no significant differences were observed between the two stages. Daily DM and DDM production of regrowth IRG were higher at T2, followed by T1. The total yield(at first and at regrowth) of DM, CP and IVDDM were significant higher for T2, followed by T3, T4 and T1 in order. At T2 stage, the yield was 11,089kg, 1,254 kg, and 7,669kg/ha in DM, CP, and IVDDM. In conclusion, the late heading to bloom stage was determined to be the optimum harvest stage for a single harvest, while the heading stage was a suitable stage of first harvest of ‘Kowinearly’ where two harvests were sought in a single year. (Key words :Forage productivity, Regrowth, Forage quality, Growth stage, IRG)

Prediction of the Chemical Composition of Fresh Whole Crop Barley Silages by Near Infrared Spectroscopy

Near infrared reflectance spectroscopy (NIRS) has become increasingly used as a rapid and accurate method of evaluating some chemical compositions in forages and feedstuff. This study was carried out to explore the accuracy of near infrared spectroscopy (NIRS) for the prediction of chemical parameters of fresh whole crop barley silages. A representative population of 284 fresh whole crop barley silages was used as a database for studying the possibilities of NIRS to predict chemical composition. Samples of silage were scanned at 1 nm intervals over the wavelength range 680~2,500 nm and the optical data were recorded as log 1/Reflectance (log 1/R) and were scanned in fresh condition. NIRS calibrations were developed by means of partial least-squares (PLS) regression. NIRS analysis of fresh whole crop barley silages provided accurate predictions of moisture, acid detergent fiber (ADF), neutral detergent fiber (NDF), crude protein (CP) and pH, as well as lactic acid content with correlation coefficients of cross-validation (R 2 cv) of 0.96, 0.81, 0.79, 0.84, 0.72 and 0.78, respectively, and standard error of cross-validation (SECV) of 1.26, 2.83, 2.18, 1.19, 0.13 and 0.32% DM, respectively. Results of this experiment showed the possibility of the NIRS method to predict the chemical parameters of fresh whole crop barley silages as a routine analysis method in feeding value evaluation and for farmer advice.

Evaluation of the quality of Italian Ryegrass Silages by Near Infrared Spectroscopy

Near infrared reflectance spectroscopy (NIRS) has become increasingly used as a rapid and accurate method of evaluating some chemical compositions in forages. This study was carried out to explore the accuracy of near infrared spectroscopy (NIRS) for the prediction of chemical parameters of Italian ryegrass silages. A population of 267 Italian ryegrass silages representing a wide range in chemical parameters and fermentative characteristics was used in this investigation. Samples of silage were scanned at 2 nm intervals over the wavelength range 680~2,500 nm and the optical data recorded as log 1/Reflectance (log 1/R) and scanned in intact fresh condition. The spectral data were regressed against a range of chemical parameters using partial least squares (PLS) multivariate analysis in conjunction with spectral math treatments to reduced the effect of extraneous noise. The optimum calibrations were selected on the basis of the highest coefficients of determination in cross validation (R 2 ) and the lowest standard error of cross validation (SECV). The results of this study showed that NIRS predicted the chemical parameters with very high degree of accuracy. The R 2 and SECV were 0.98 (SECV 1.27%) for moisture, 0.88 (SECV 1.26%) for ADF, 0.84 (SECV 2.0%), 0.93 (SECV 0.96%) for CP and 0.78 (SECV 0.56), 0.81 (SECV 0.31%), 0.88 (SECV 1.26%) and 0.82 (SECV 4.46) for pH, lactic acid, TDN and RFV on a dry matter (%), respectively. Results of this experiment showed the possibility of NIRS method to predict the chemical composition and fermentation quality of Italian ryegrass silages as routine analysis method in feeding value evaluation and for farmer advice.

Evaluation of Characteristics, Winter Survival and Forage Production for Warm Season Grass in the Mid-Southern Regions of Korea

Field studies were conducted from the years 2009 to 2012 in order to determine the cultivation limit as well as to evaluate the characteristics and forage production of warm season grass in Korea. Two bermudagrass [Cynodon dactylon (L.) Pers.] cultivars, two bahiagrass (Paspalum notatum Flugge) cultivars and a Kleingrass [Panicum coloratum L.] cultivar were compared for forage production and quality in the mid-southern regions of Korea. The experimental design was a randomized block design (RBD) with three replications. The number of days to seedling emergence for bremudagrass and bahiagrass was observed as approximately 12 days and 28 days after seeding, respectively. In Kwangju, the heading dates of bahiagrass and kleingrass were 21 August and 10 July, respectively,. Warm season grass did not winter in the mid-regions (Kimjea, Cheonan) of Korea. All of the Bermudagrass cultivars had higher dry matter (DM) than bahiagrass at the first harvest. The dry matter yield of kleingrass was usually greater than the other entries at all study sites. Peak forage DM production of bermudagrass and bahiagrass cultivars occurred in June and July, respectively. The contents of crude protein (CP) and total digestibility nutrient (TDN) for bermudagrass cultivars were usually greater than the other entries at all study sites. Further, acid detergent fiber (ADF) and in vitro DM digestibility (IVDMD) were similar across all cultivars. (

Effect of Conditioning Methods and Tedding Frequency on the Drying Rate and Quality in Italian Ryegrass Hay

A field experiment was carried out to determine the effects of conditioning methods and tedding frequency on the drying rate and quality of Italian ryegrass hay. Italian ryegrass was cut with three types of mower conditioners (un conditioned, impeller, roller) and tedded with rake-tedder once or twice daily during field curing. The field drying rate of Italian ryegrass hay was the highest in roller conditioner. Conditioning treatment shorten the date from 1 to 1.5 compare with unconditioned. Drying rate of Italian ryegrass plant had been affected by tedding frequency within 3 days after it was cut, but it was ineffective after 3 days. There is no effect on acid detergent fiber (ADF) and neutral detergent fiber (NDF) but effect crude protein (CP) and relative feed value (RFV) by conditioning treatment in nutritive value of Italian ryegrass hay.

Comparison of callus induction and plant regenerationfrom twenty tall fescue varieties

Tall fescue (Festuca arundinacea Schreb.) is an important grass species both as turf and forage. In this study, 20 varieties of tall fescue were used to investigate the effects of genetic variations in tissue culture response. Plant genotype had a significant effect both on callus formation and plant regeneration in tall fescue. The forage type tall fescue varieties readily formed callus than turf type tall fescue varieties. Of all the forage varieties studied, Jesup, Greenmaster, Kentucky-31 and Fawn not only formed callus at a higher frequency but also had a high regeneration when compared with other varieties. These results can be used not only to provide additional improvements in the plant regeneration frequency from transgenic callus, but also useful for molecular breeding of tall fescue through genetic transformation.

Factors influencing callus induction and plant regeneration of Dahurian wildrye grass ( Elymus dahuricus L.)

Establishment of highly efficient and reproducible regeneration system would greatly influence the efforts of improvement of Elymus sp. through gene transfer technology. A suitable callus induction and efficient regeneration protocol for Dahurian wildrye grass ( Elymus dahuricus L.) was developed. It consisted of 3.0 mg/L 2,4 dichlorophenoxyacetic acid (2,4-D) or Dicamba + 1.0 g/L casein hydrolysate (CH) + 300 mg/L L-proline + 30 g/L sucrose in MS, and showed the highest percentage of callus induction. Highest (51%) regeneration was obtained from N6 medium containing 1.0 mg/L 2,4-D + 3.0 mg/L N 6 -benzylaminopurine (BA) + 1.0 g/L CH + 300 mg/ L L-proline + 30 g/L sucrose. Thus, optimization of regeneration frequency using mature seeds as explants material may offer a simple and efficient protocol for Dahurian wildrye grass that may improve molecular breeding of this species. Key words : Dahurian wildrye grass, Elymus dahuricus L., callus, plant regeneration.