here - IRRI books - International Rice Research Institute

Horie T. 2005. Determination of the yield potential and associated
traits in rice. Gamma Field Symposia 43. Institute of Radiation
Breeding, NIAS. (In press.)
Huang J, Yang H, Dong G, Wang Y, Zhu J, Yang L, Shan Y. 2002.
Effects of free-air CO 2 enrichment (FACE) on yield formation
in rice (Oryza sativa). Chinese J. Appl. Ecol. 13:1210-
1214.
IPCC (Inter-Governmental Panel on Climate Change). 2001. Climate
change 2001: the scientific basis. Contribution of working
group I to the third assessment report of IPCC. London
(UK): Cambridge University Press.
Kim H-Y, Horie T, Nakagawa H, Wada K. 1996. Effects of elevated
CO 2 concentration and high temperature on growth and yield
of rice: the effect on yield and its components on Akihikari
rice. Jpn. J. Crop Sci. 65:644-651.
Kim H-Y, Lieffering M, Kobayashi K, Okada M, Matthew WM,
Gumpertz M. 2003. Effects of free-air CO 2 enrichment and
nitrogen supply on the yield of temperate paddy rice crops.
Field Crops Res. 83:261-270.
Matthews RB, Horie T, Kropff MJ, Bachelet D, Centeno HG, Shin
JC, Mohandas S, Singh S, Defeng Z, Lee MH. 1995. A regional
evaluation of the effect of future climate change on
rice production in Asia. In: Matthews RB, Kropff MJ, Bachelet
D, van Laar HH, editors. Modeling the impact of climate
change on rice production in Asia. Wallingford (UK): CAB
International, p 95-139.
Ueda T, Nakagawa H, Okada K, Horie T. 2000. Varietal differences
in yield and spikelet fertility of rice in response to elevated
CO 2 concentration and high temperature. Jpn. J. Crop Sci.
69(extra issue 1):112-113.
Yoshida H, Horie T, Ohnishi M, Katsura K. 2003. Analysis of genotype
by environment interaction in yield formation processes
of rice grown under a wide environmental range in Asia. 2. A
model explaining genotypic and environmental variation in
spikelet number per unit area. Jpn. J. Crop Sci. 72(extra issue
2):90-91.
Yoshida H, Horie T. 2005. Analysis of genotype by environment
interaction in yield formation processes of rice grown under a
wide environmental range in Asia. 5. Jpn. J. Crop Sci. 73(extra
issue 2). (In preparation.)
Ziska LH, Namuco O, Moya T, Quilang J. 1997. Growth and yield
response of field-grown tropical rice to increasing carbon dioxide
and air temperature. Agron. J. 89:45-53.
Notes
Authors’ address: Graduate School of Agriculture, Kyoto University,
Sakyo-ku, Kyoto 606-8502, Japan, e-mail:
horiet@adm.kais.kyoto-u.ac.jp.
Monitoring rice growth and development using
a crop model: the case of northern Japan
Masaharu Yajima
Rice yield has increased dramatically with the development of
improved nursery techniques, new varieties resistant to lodging
and diseases, and new yield-enhancing agrochemicals.
Although rice farmers commonly attain high yield, yield fluctuations
sometimes occur because of unfavorable weather conditions
during the rice-cropping season in particular areas. A
recent study shows that summer weather in northern Japan since
1982 appears to exhibit a distinct five-year cycle, with a pressure
difference between Wakkanai in Hokkaido and Sendai in
Tohoku. The temperature also follows similar five-year cycles
and the second year of each cycle is typical of the Yamase, a
cold northeasterly wind, and is consistent with the cool summer
in northern Japan (Kanno 2004). For instance, severe spikelet
sterility because of cool weather that occurred during meiosis
of the pollen mother cell to the flowering stage of the rice
crop in some areas of Tohoku Region in 1980, 1988, 1993,
and 2003 greatly reduced yield.
This paper intends to describe the research approach and
initial results of wide-area monitoring of crop growth and development
in 1993 and 2003 using a rice crop model (Yajima
1996) to construct the initial version of a climatic early warning
system against cool summer damage of rice under changing
climate.
Monitoring crop growth and development
using a rice crop model
The approach involved using the development stage and spikelet
sterility and yield models, and crop and geo-climatic data
sets to develop a prediction system.
Based on the development stage (DVS) model designed
by Horie (1987), values of 0, 1, and 2 are assigned to emergence
(seed germination), heading, and physiological maturity,
respectively. The value of DVS at any point of crop development
is calculated by integrating the developmental rate
(DVR), expressed as a function of daylength and daily mean
temperature, with time.
Generally, dry matter accumulation at any point in rice
growth is proportional to the accumulated solar radiation intercepted
by the canopy, except at the final stage of rice growth,
when DVS is close to 2. The model used to estimate daily dry
matter increase was adopted from Monteith (1977).
The spikelet sterility model on the relationship between
spikelet sterility and cool-temperature sensitivity of the rice
plant at the panicle development stage was proposed by Yajima
et al (1989), with the following equation:
Session 19: Climate change and rice production 539