Compare of the Agronomic Characteristics of Korean Rice Varieties at Jinbu of Korea and Malong of China

A survey of different weedy rice biotypes was conducted in rice field areasof Nueva Ecija from CY 2004-2006 to determine their prevalence, agronomiccharacteristics and biology. Surveys and quadrat samplings were conducted inrandom alongside of the roads to gather data on prevalence, height, numberof panicles/plant and density/m of weedy rice as well as the cultivated onesthey were associated. Studies on seed germination test, biology and agronomical characteristics of different weedy rice biotypes were also conducted at thelaboratory and screenhouse of Crop Protection Division, Philippine Rice ResearchInstitute. Five weedy rice biotypes designated as WR-NE 1, WR-NE 2, WR-NE3, WR-NE 4 and WR-NE 5 were found distributed almost everywhere in ricefields of Nueva Ecija. Among the biotypes, WR-NE 1 was the most common inmany rice fields. Prevalence of all biotypes around the province ranged from 1to 17%. In the field, all biotypes were found taller but had fewer panicles plantthan cultivated rice varieties. In the laboratory, all weedy rice biotypes emergedearlier than PSB Rc82 and IR64. Under screenhouse condition, all weedy ricebiotypes were taller, produced more leaves and culms plant than the cultivatedrice. WR-NE 5 was the tallest biotype while WR-NE 1 and WR-NE 2 had themost number of leaves and culms plant-1-1. All biotypes matured earlier but hadno seed shattering characteristics. The biotypes had comparable values in termsof flag leaf areas and LAI/plant with PSB Rc82. Shoot dry weight and number ofpanicles/plant of all biotypes was significantly higher than the control varieties.WR-NE 4 and WR-NE 5 had the longest panicles, longer and wider grains.Grains/panicle was highest in WR-NE 5 (102 grains/panicle). Grain lengthwidthratio (GLWR)of all biotypes, however,weresignificantly lowerthan thetwocontrolvarieties.WR-NE1 and WR-NE4 had the longest length of awnwhileWR-NE4 and WR-NE5 had the highest grain weight(both at 24 g/1000grains).The growthand developmentof the fiveweedyrice biotypes weremuchadvantageouscomparedto selected cultivarssuggesting their competitivenessandthreatin achieving the potential yield and quality of harvestedcultivatedrice. Keywords - Plant ecology, prevalence, agronomic characteristics, weed biology, biotype,Oryza sativa L., weedy rice, experimental design, Philippines

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Growth Characteristics and Yield of Korean Rice Varieties in Myanmar

Journal of the Korean Society of International Agriculture ◽

10.12719/ksia.2016.28.3.335 ◽

2016 ◽

Vol 28 (3) ◽

pp. 335-341

Author(s):

Hong-Kyu Park ◽

◽

Jae-Hyun Kim ◽

Eong-Gi Jung ◽

Jong-Rok Son ◽

...

Keyword(s):

Growth Characteristics ◽

Rice Varieties ◽

Korean Rice

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Properties and Digestibility of Octenyl Succinic Anhydride-Modified Japonica-Type Waxy and Non-Waxy Rice Starches

Molecules ◽

10.3390/molecules24040765 ◽

2019 ◽

Vol 24 (4) ◽

pp. 765 ◽

Cited By ~ 3

Author(s):

Junhee No ◽

Saehun Mun ◽

Malshick Shin

Keyword(s):

Succinic Anhydride ◽

Emulsion Stability ◽

Rice Starch ◽

Gelatinization Temperature ◽

Rice Varieties ◽

Octenyl Succinic Anhydride ◽

Waxy Rice ◽

Korean Rice ◽

Different Levels ◽

Waxy Rice Starch

Waxy and non-waxy rice starches from japonica type Korean rice varieties were esterified with different levels of octenyl succinic anhydride (OSA), and the molecular structure of amylopectin (AP), digestibility, and emulsion stability were investigated. As OSA levels increased, the degree of substitution, granule size, peak and final viscosities, emulsion stability, and short chain of AP increased. However, the gelatinization temperature and enthalpy, and digestibility decreased. All OSA esterified starches showed a new band at 1723 cm−1, but maintained A-type crystallinity. The DP6-12 of AP in waxy rice starch (WRS) was higher than that in non-waxy rice starch (NRS) with increasing OSA levels. Because the amylose and long chain of AP accessed easily with OSA groups, the digestibility of NRS was lower than that of WRS. The emulsion stability was higher in WRS than in NRS. From the above results, it is suggested that amylose should have a higher affinity with OSA esterification than AP and that the emulsion stability should increase in WRS, but the digestibility should decrease in NRS after OSA modification.

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Testing the simulation capability of APSIM-ORYZA under different levels of nitrogen fertiliser and transplanting time regimes in Korea

Australian Journal of Experimental Agriculture ◽

10.1071/ea05363 ◽

2007 ◽

Vol 47 (12) ◽

pp. 1446 ◽

Cited By ~ 12

Author(s):

Xike Zhang ◽

Jae-Hong Lee ◽

Yahya Abawi ◽

Young-ho Kim ◽

David McClymont ◽

...

Keyword(s):

Management Practices ◽

Field Experiments ◽

Agricultural Research ◽

Cropping System ◽

Measured Data ◽

Rice Varieties ◽

Early Maturing ◽

Photoperiod Sensitive ◽

Korean Rice ◽

Management Issues

APSIM-ORYZA is a new functionality developed in the APSIM framework to simulate rice production while addressing management issues such as fertilisation and transplanting, which are particularly important in Korean agriculture. To validate the model for Korean rice varieties and field conditions, the measured yields and flowering times from three field experiments conducted by the Gyeonggi Agricultural Research and Extension Services (GARES) in Korea were compared against the simulated outputs for different management practices and rice varieties. Simulated yields of early-, mid- and mid-to-late-maturing varieties of rice grown in a continuous rice cropping system from 1997 to 2004 showed close agreement with the measured data. Similar results were also found for yields simulated under seven levels of nitrogen application. When different transplanting times were modelled, simulated flowering times ranged from within 3 days of the measured values for the early-maturing varieties, to up to 9 days after the measured dates for the mid- and especially mid-to-late-maturing varieties. This was associated with highly variable simulated yields which correlated poorly with the measured data. This suggests the need to accurately calibrate the photoperiod sensitivity parameters of the model for the photoperiod-sensitive rice varieties in Korea.

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