An alternative approach for predicting the heading date of rice plants was developed by using the 30-yr averaged normal heading date for the input of a developmental index model instead of using the information on the rice transplanting date and the developmental index on that date. This approach is based on the fact that the normal heading date has less spatial heterogeneity compared with the standard input variables and facilitates prediction of the spatial variation of the heading date. The model predicted the inter-regional variation of the heading date in the Tohoku district of Japan within 2 days for its root mean square errors (RMSE), which is similar to that of the traditional developmental index (DVI) model, and well reproduced spatial variation of the date Tohoku district in extremely hot/cold years, although further validation is needed to prove the model accuracy.

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Investigations have been carried out to determine the protein, fat, ash, phosphorus, potassium, and magnesium content of rice kernel of 4 lowland non-glutinous varieties at intervals of 10 days from dough ripening (20 days after ) to ripening (70 days after heading). From dough ripening to full ripening, the chemical composition varied widely and each of the components decreased on dry matter and increased in 1000 kernels. After full ripening, the chemical composition had a tendency to vary slightly. The protein and fat content decreased and the ash and potassium content increased on dry matter. On the other hand, the protein content increased or decreased after the initial increasing and the ash, phosphorus, potassium, and magnesium content increased and the fat content decreased in 1000 kernels.

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As a consequence of extreme changes in climate, farming scale, and social structure, the requirements for rice yield potential and grain quality have been changing in Japan. To meet the demands of consumers, rice processing companies, and paddy farmers, “Tsukiakari” and “Niji-no-kirameki” were developed as high-yielding and highly palatable rice cultivars. The palatability of both cultivars is excellent and is as high as the leading Japanese cultivar, “Koshihikari.” The yield potential of the new cultivars is over 700 g m⁻² (brown rice, 15% moisture basis), and their shorter culm lengths provide greater lodging tolerance. “Tsukiakari” has been mainly distributed in the northern and central regions of Honshu, whereas “Niji-no-kirameki” has been distributed in the central and western regions. An early maturity cultivar, “Tsukiakari,” is useful for separating harvest schedule from “Koshihikari.” “Niji-no-kirameki” has been replacing “Koshihikari” in heat-vulnerable regions due to its superior heat resilience during the ripening period. Establishing proper cultivation methods for “Tsukiakari” and “Niji-no-kirameki” through multiple environmental tests helps local farmers efficiently manage their farms and produce high-yielding and highly palatable crops. Superior characteristics of “Tsukiakari” and “Niji-no-kirameki” will be useful to develop new rice genotypes that highly meet the needs of the times.

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A quantitative trait locus (QTL) analysis was conducted on grain appearance in Emi-no-kizuna, a rice cultivar that has superior and stable appearance of the brown rice grain and high tolerance to high temperature stress, by using F₃ lines derived from Emi-no-kizuna and Tomohonami. The investigation was performed 2013 and 2015. In summer 2013 the air temperature was higher and the larger differences in grain appearance were observed. In the QTL analysis, a highly contributing locus, qGA8, was detected at the end of the short arm of chromosome 8. Because trends of reduced the occurrence of white immature kernel and increased the percentage of perfect grain were observed in Emi-no-kizuna genotype in both years, qGA8 is likely to be an important QTL that is dominant in the superior grain appearance of Emi-no-kizuna. Also, qGA8 was linked to a QTL associated with days to heading. Another QTL, qGA7, associated with grain appearance was detected on chromosome 7 in 2013. Because no negative correlation was found between the genotype of qGA8 and thousand grain weight, it should be possible to breed cultivars that possess Emi-no-kizuna genotype qGA8 without a decrease in thousand grain weight.

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筆者ら(1983)は，第10染色体を含む5相互転座系統，台中65号(T65)の同質雄性不稔および稔性回復系統を用いた三系交雑Fユ植物における出穂期分離が25～39日に亘り1頂曲線分布を示すこと，供試相互転座系統はいずれも第10染色体の早生遺伝子を持つことを報告した.その後，それら相互転座系統の内の1つならびにその母品種より2つの早生遺伝子(Ef-1，Ef-x)が同定された(Sato et al1988，Sato et al 1992).しかし，この三系交雑F1植物での出穂期分離をそれら2遺伝子のみで説明できるものではなく，相互転座系統は更にいくつかの早生遺伝子を有していることが考えられた.そこで，この早生遺伝子を同定するために，前実験で用いた5相互転座系統を含む17系統並びに1つの標識遺伝子系統を早生遺伝子の供与親とし，T65を反復親とする10回の戻し交雑により18種のT65の同質早生遺伝子系統を育成した

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Forage rice (Oryza sativa L.) must be cost competitive with other fodders, and thus an important goal is increasing its dry matter (DM) and total digestible nutrient (TDN) yields, while reducing labor and costs. Although the direct seeding of rice does not have higher yield stability than transplanting, it has the potential to reduce labor and costs. The objective of this study was to determine the effects of seeding rate (2, 4, or 6 g m^–2) and row spacing (10 or 30 cm) on DM and TDN yields in direct-seeded and double-harvested forage rice in a well-drained paddy field. The seeding rate did not affect the total DM and TDN yields of the first and second crops, although those total yields were higher at 10 cm row spacing than at 30 cm row spacing. The DM yield and tiller number of the first crop increased with increasing seeding rate. Both were higher at 10 cm row spacing than at 30 cm row spacing. The seeding rate did not affect the DM and TDN yields of the second crop harvested at heading, although those yields were higher at 10 cm row spacing than at 30 cm row spacing. Neither seeding rate nor row spacing affected the DM and TDN yields of the second crop harvested at dough ripe. Thus, increasing the seeding rate is effective for increasing the DM and TDN yields of the first crop and reducing row spacing is effective for increasing total DM and TDN yields of the first and second crops. This cultivation method is expected to facilitate forage rice production by reducing labor and costs in temperate regions.

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The objectives of this study were to estimate the progress in wheat genetic yield potential, associated with changes in some agronomic traits, under different N rates. Twenty-four cultivars of winter wheat (T. aestivum L.) representing most of the cultivars released in Serbia from 1955 to 2006 were analyzed. The cultivars were grown for four years (2005–2008) in field trails with two levels of agronomic inputs (low nitrogen-N₄₅ and high nitrogen-N₁₁₀). Data were collected on 1000-kernel weight, kernels per spike, kernels per square meter, spikes per square meter, plant height, harvest index, heading time and grain yield. Mean difference between the two fertilization levels was 0.44 t ha⁻¹. The average rate of increase in yield potential per year of release, estimated from the slope, was 41 kg ha⁻¹ year⁻¹ and it was significantly different from zero (P ≤ 0.01). It was 35 kg ha⁻¹ year⁻¹ or 0.55% at the low level of N input, and 46 kg ha⁻¹ year⁻¹ or 0.68% at the high level of N input. This suggests that modern cultivars are better adapted to high N input. Our results suggested that individual contribution of the most of analyzed traits may vary depending on the genotype as well as environmental conditions.

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　Crop phenology models play a pivotal role in predicting yields under climate change. Cultivar-specific model parameters are essential for accurate prediction, but their estimation generally requires elaborate and laborious experiments, and such parameter sets have therefore been available only for a small number of cultivars. We propose methodology for estimating phenological parameters, combining a stochastic parameter estimation method (genetic algorithm) with the use of a database comprising 30 years of records from variety trials conducted at experimental stations across Japan. Optimal parameter sets were selected based on the results of cross-validation tests. This methodology allowed us to estimate phenological parameters objectively. We estimated phenological parameters for the 10 leading cultivars currently planted in Japan, and showed that these parameters reflect the cultivars' sensitivity to temperature and/or photoperiod. The proposed methodology can be used to provide quantitative evaluations of the environmental responses of rice cultivars, without relying on elaborate and laborious experiments, and substantially improves the efficiency of phenological trait phenotyping.

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The Air Traffic Control (ATC) simulator is usually composed of radar displays, display control units, a computer, displays for pseudo-pilots, etc. The controller issues various instructions by observing movements of simulated aircraft on the radar display, and then the pseudo-poilot inputs appropriate commands to the computer and responds to the controller.

This paper describes an application of voice processing techniques to the ATC simulation. It was planned as part of a development program of a dynamic simulation system to analyze and evaluate the sector capacity and enroute ATC procedures.

The voice recognition system (DP-200) of the Nippon Electric Corporation with a voice response unit was chosen to process controller-initiated instructions and to simulate pilotinitiated communications. The DP-200 has a continuous word recognition capability and a syntax processing function, and the speaker has to store his own voice pattern before using it.

Prior to integration of the simulation system, we conducted a preliminary test and evaluation of its voice recognition capabilities and basic voice response functions by using a microcomputer system with a specially designed syntax processing program for the ATC phraseologies and a simulation program. A recognition rate for the ATC phraseologies was about 90 percent in terms of the word unit.

The voice recognition system used is sensitive to the speaker's intonation, and the user has to train and familiarize himself with its characteristics. Therefore, further improvements are required in word recognition functions if the voice recognition system is to be applied to actual ATC operations.

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