등숙기 온도에 따른 쌀가루 가공용 벼의 등숙특성 변이 구명 = Effects of Temperature on Grain Filling Properties of Rice Flour Varieties during the Ripening Stage

다국어 초록 (Multilingual Abstract)

The processing of rice is one of the measures to expand the scope of rice use in response to the decrease in rice consumption. Since the main ingredient of rice processing is rice flour, “rice flour varieties” have been bred with the aim to improve the productivity and quality of rice flour. In order to study the variation in the ripening characteristics of rice flour varieties with respect to temperature, the average temperature after heading date was set at 28°C (33/23°C), 22°C (27/17°C), and 18°C (23/13°C) inside the phytotron. We used Saenuri as non-glutinous rice variety, Seolgaeng as soft-type rice flour variety, and Baromi2 as powdered rice flour variety. At high temperatures (28°C), the grain weight of Baromi2 decreased by 21%. Its starch content also decreased by more than 10%, which was significantly lower than that of Saenuri and Seolgaeng. At low temperatures (18°C), the grain weight and starch content slightly increased or were similar in all varieties. An analysis of changes in the grain weight due to effective accumulated temperature through the sigmoid function showed that the velocity of grain-filling slowed significantly when Baromi2 was exposed to low temperature during the ripening stage compared to the other varieties. Therefore, the transplanting time of Baromi2 should be delayed to avoid high temperatures during the ripening stage. However, because the ripening period is not properly secured under low temperature conditions, grain filling may not be sufficient.

국문 초록 (Abstract)

쌀가루용 품종의 등숙기 온도에 따른 등숙특성 변이를구명한 내용은 다음과 같다.
1. 고온(28°C)에서는 바로미2의 천립중이 21% 감소하면서새누리(6% 감소)와 설갱(12% 감소)에 비해 크게 줄어들었으며, 전분함량의 감소 또한 바로미2에서 10% 이상으로 새누리와 설갱의 1∼3% 감소와 대비되었다.
2. 저온(18°C)에서는 새누리나 설갱에 비해 바로미2의 등숙 속도가 매우 감소하였으며 특히 등숙 초반에 종실중의 증가가 매우 느렸다. 그러나 최종 천립중 및 전분함량은 22°C보다도 약간 증가하며 다른 품종과도 비슷한것을 확인하였다.
3. 앞서 언급한 것처럼 쌀가루 가공용 품종 중 분질미(바로미2)는 등숙기 온도에 민감하기 때문에 추후 분질미 재배시 등숙기에 고온을 피할 수 있도록 이앙시기를 늦추는 편이 좋으며, 다만 과도하게 늦출 경우 저온조건에서등숙기간을 제대로 확보하지 못하여 등숙이 충분히 되지않을 수 있기 때문에 주의가 필요하다.

참고문헌 (Reference)

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