Abstract
In a previous paper, we suggested that the sink capacity, defined as the spikelet weight with the exclusion of grain per unit leaf area at harvest, was too low to allow further increase in grain yield of rice varieties cultivated in the warmer part of Japan. In this paper, we compare the characteristics of grain production among old and new types of cultivars growing in the warmer part of Japan and improved japonica-indica hybrid cultivars such as Milyang 23 and Yoo Sin. Milyang 23 showed higher yields, higher total dry matter production and higher harvest index in plots with standard and heavy nitrogen application (Fig. 1). In all cultivars used in this experiment the sink capacity and leaf area increased following heavy nitrogen application (Fig. 2). It was remarkable that both Korean cultivars had a larger number of spikelet per unit leaf area (49, 000/m2) as compared with the Japanese cultivars (37, 000/m2) (Table 1). This difference was ascribed to variations in the number of spikelets per ear between Japanese and Korean cultivars. The Korean cultivars showed a lower increase in leaf area and a higher increase in sink capacity in relation to nitrogen absorption during the period from transplanting to heading (Fig. 3). The sink/source ratio, representing the ratio of sink capacity to leaf area at heading, was much higher in both Korean cultivars than in the Japanese cultivars (Table 2). Among the Japanese cultivars the old types had a higher ratio because they had larger ear than the new types of cultivars (Table 2). Therefore, it is considered that the Korean cultivars can produce ears with higher sink capacity without displaying excessive leaf growth. As a result, the harvest index remained high when total dry weight increased following heavy nitrogen application (Fig. 1). The Korean cultivars, with short culm and large ears, showed two interesting feature, as follows; compared with the Japanese cultivars their sink/source ratio was higher than that of old types although they had the short culm of the new types of cultivars. However, since the Korean cultivars have several disadvantages related to taste and tolerance of disease and cold, it will be necessary to develop new cultivars showing with the advantages of the Korean cultivars, while minimaizing their shortcomings.
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Claims 15
Claim · model-written summary
Milyang 23 had higher yield under standard and heavy nitrogen application.
- Taxon
- Rice
Oryza sativat0 - Material
- Milyang 23e0
- Treatment
- standard and heavy nitrogen applicatione0
- Outcome
- yieldse0
- Direction
- highere0
- Setting
- plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Milyang 23 showed higher yields, higher total dry matter production and higher harvest index in plots with standard and heavy nitrogen application”
t0“Rice Cultivars”
Claim · model-written summary
Milyang 23 had higher total dry matter production under standard and heavy nitrogen application.
- Taxon
- RiceOryza sativat0
- Material
- Milyang 23e0
- Treatment
- standard and heavy nitrogen applicatione0
- Outcome
- total dry matter productione0
- Direction
- highere0
- Setting
- plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Milyang 23 showed higher yields, higher total dry matter production and higher harvest index in plots with standard and heavy nitrogen application”
t0“Rice Cultivars”
Claim · model-written summary
Milyang 23 had a higher harvest index under standard and heavy nitrogen application.
- Taxon
- RiceOryza sativat0
- Material
- Milyang 23e0
- Treatment
- standard and heavy nitrogen applicatione0
- Outcome
- harvest indexe0
- Direction
- highere0
- Setting
- plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Milyang 23 showed higher yields, higher total dry matter production and higher harvest index in plots with standard and heavy nitrogen application”
t0“Rice Cultivars”
Claim · model-written summary
Heavy nitrogen application increased sink capacity in all tested cultivars.
- Taxon
- RiceOryza sativat0
- Treatment
- heavy nitrogen applicatione0
- Outcome
- sink capacitye0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In all cultivars used in this experiment the sink capacity and leaf area increased following heavy nitrogen application”
t0“Rice Cultivars”
Claim · model-written summary
Heavy nitrogen application increased leaf area in all tested cultivars.
- Taxon
- RiceOryza sativat0
- Treatment
- heavy nitrogen applicatione0
- Outcome
- leaf areae0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In all cultivars used in this experiment the sink capacity and leaf area increased following heavy nitrogen application”
t0“Rice Cultivars”
Claim · model-written summary
Korean cultivars had 49,000 spikelets per unit leaf area versus 37,000 in Japanese cultivars.
- Taxon
- RiceOryza sativat0
- Material
- Korean cultivarse0
- Outcome
- number of spikelet per unit leaf areae0
- Direction
- largere0
- Value
- 49, 000/m2e0
- Qualifier
- 37, 000/m2e0
- Comparator
- Japanese cultivarse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“both Korean cultivars had a larger number of spikelet per unit leaf area (49, 000/m2) as compared with the Japanese cultivars (37, 000/m2)”
t0“Rice Cultivars”
Claim · model-written summary
The Korean versus Japanese difference in spikelets per leaf area was attributed to spikelets per ear.
- Taxon
- RiceOryza sativat0
- Material
- Korean cultivarse0
- Outcome
- differencee0
- Qualifier
- variations in the number of spikelets per eare0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This difference was ascribed to variations in the number of spikelets per ear between Japanese and Korean cultivars”
t0“Rice Cultivars”
Claim · model-written summary
Korean cultivars had a lower increase in leaf area relative to nitrogen absorption from transplanting to heading.
- Taxon
- RiceOryza sativat0
- Material
- Korean cultivarse0
- Outcome
- leaf areae0
- Direction
- lower increasee0
- Qualifier
- in relation to nitrogen absorption during the period from transplanting to headinge0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The Korean cultivars showed a lower increase in leaf area and a higher increase in sink capacity in relation to nitrogen absorption during the period from transplanting to heading”
t0“Rice Cultivars”
Claim · model-written summary
Korean cultivars had a higher increase in sink capacity relative to nitrogen absorption from transplanting to heading.
- Taxon
- RiceOryza sativat0
- Material
- Korean cultivarse0
- Outcome
- sink capacitye0
- Direction
- higher increasee0
- Qualifier
- in relation to nitrogen absorption during the period from transplanting to headinge0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The Korean cultivars showed a lower increase in leaf area and a higher increase in sink capacity in relation to nitrogen absorption during the period from transplanting to heading”
t0“Rice Cultivars”
Claim · model-written summary
Korean cultivars had a much higher sink/source ratio than Japanese cultivars.
- Taxon
- RiceOryza sativat0
- Material
- Korean cultivarse0
- Outcome
- sink/source ratioe0
- Direction
- much highere0
- Comparator
- Japanese cultivarse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The sink/source ratio, representing the ratio of sink capacity to leaf area at heading, was much higher in both Korean cultivars than in the Japanese cultivars”
t0“Rice Cultivars”
Claim · model-written summary
Old Japanese cultivars had a higher sink/source ratio than new types because of larger ears.
- Taxon
- RiceOryza sativat0
- Material
- old typese0
- Outcome
- ratioe0
- Direction
- highere0
- Qualifier
- larger eare0
- Comparator
- new types of cultivarse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Among the Japanese cultivars the old types had a higher ratio because they had larger ear than the new types of cultivars”
t0“Rice Cultivars”
Claim · model-written summary
Korean cultivars were interpreted as producing ears with higher sink capacity without excessive leaf growth.
- Taxon
- RiceOryza sativat0
- Material
- Korean cultivarse0
- Outcome
- sink capacitye0
- Direction
- highere0
- Qualifier
- without displaying excessive leaf growthe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the Korean cultivars can produce ears with higher sink capacity without displaying excessive leaf growth”
t0“Rice Cultivars”
Claim · model-written summary
Harvest index remained high as total dry weight rose after heavy nitrogen application.
- Taxon
- RiceOryza sativat0
- Treatment
- heavy nitrogen applicatione0
- Outcome
- harvest indexe0
- Direction
- remained highe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the harvest index remained high when total dry weight increased following heavy nitrogen application”
t0“Rice Cultivars”
Claim · model-written summary
Korean cultivars combined a higher sink/source ratio than old Japanese types with the short culm of new types.
- Taxon
- RiceOryza sativat0
- Material
- Korean cultivarse1
- Outcome
- sink/source ratioe0
- Direction
- highere0
- Qualifier
- short culm of the new types of cultivarse0
- Comparator
- old typese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“their sink/source ratio was higher than that of old types although they had the short culm of the new types of cultivars”
e1“The Korean cultivars, with short culm and large ears”
t0“Rice Cultivars”
Claim · model-written summary
The authors recommend developing cultivars with Korean cultivar advantages while minimizing taste, disease-tolerance and cold-tolerance shortcomings.
- Taxon
- RiceOryza sativat0
- Outcome
- develop new cultivars showing with the advantages of the Korean cultivarse0
- Qualifier
- disadvantages related to taste and tolerance of disease and colde1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“it will be necessary to develop new cultivars showing with the advantages of the Korean cultivars, while minimaizing their shortcomings”
e1“the Korean cultivars have several disadvantages related to taste and tolerance of disease and cold”
t0“Rice Cultivars”
The same questions in other papers
nitrogen · growth · Oryza sativa (rice)Positive and negative results
401 papers in the same direction as this paper · 101 in the opposite direction · 8 reporting no difference from an alternative
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- negative
- negative
507 papers more in this group
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