• 한국작물학회지
• /
• 제38권5호
• /
• pp.449-457
• /
• 1993

온도가 쌀보리와 맥주보리의 출엽속도와 출엽간격에 미치는 영향을 구명하고자 쌀보리 3품종(능쌀보리, 새쌀보리, 향천과 001)과 맥주보리 3품종(두산 8호, 사천006, 진광보리)을 향온 7수준(4, 8, 12, 16, 20, 24, 28$^{\circ}C$)과 변온 7수준[6/2(명기 / 암기), 10/6, 14/10, 18/14, 22/18, 26/22, 30/$25^{\circ}C$]으로 유지시킨 생장상에서 4엽기까지 키우면서 매일 주간엽수를 조사하여 출엽속도 및 출엽간격를 산출한 결과를 요약하면 다음과 같다. 항온과 변온에 관계없이 공시품종 모두 동일 온도내에 있어서는 출아후 일수가 증가됨에 따라 주간 출엽수도 직선적으로 증가되었다. 평균기온 28$^{\circ}C$를 제외하고는 출아속도와 출아간격이 항온과 변온간에 현저한 차이를 보이지 않았다. 출아속도와 출아간격은 품종간에 유의한 차이가 있었고 동일 품종내 온도간에도 현저한 차이가 있었다. 평균기온이 증가됨에 따라 일당 출아속도는 출아 최적온도까지 곡선적으로 증가된 다음 감소되었는데, 6품종의 출아 최적온도는 20.1～21.5$^{\circ}C$로 품종간 현저한 차이는 없었으나 출아 최적온도에서의 출엽속도는 쌀보리가 0.202～0.226엽/일, 맥주보리가 0.231～0.241엽/일으로 맥주보리가 큰 경향이었다. 평균이온이 증가됨에 따라 유효적산온도당 출엽속도는 지수함수적으로 감소되었고, 출엽간격(일엽당 적사온도)은 지수함수적인 증가를 보였는데, 6품종의 평균 출엽간격은 4$^{\circ}C$에서 46.2GDD/엽, 28$^{\circ}C$에서 129.3GDD/엽이었다.

• 한국작물학회지
• /
• 제55권3호
• /
• pp.259-267
• /
• 2010

This study was performed at Rice and Winter Cereal Crops Department of NICS during 2007 and 2008 to investigate the characteristics of rice leaf emergence and to obtain basic data which can be used for rice growth simulation model by which we can forecast rice growth stage and heading date accurately under different cultivars, transplanting date, and climatic conditions. To confirm leaf emergence rate according to rice maturing ecotype, we surveyed the leaf emergence rate and heading date of Unkwangbyeo, Hwayoungbyeo and Nampyeongbyeo which are early maturing, medium maturing and medium-late maturing cultivars, respectively, according to seedling raising duration and transplanting time. When seedling duration was 15 days, the growth duration between transplanting time and completion of flag leaf emergence on main culm were 51.5~78.3 days in Unkwangbyeo, 55.3~87.9 days in Hwayoungbyeo and 58.4~98.4 days in Nampyeongbyeo, respectively. When seedling duration was 30 days, they were 50.1~75.5 days in Unkwangbyeo, 52.4~84.7 days in Hwayoungbyeo and 56.4~93.8 days in Nampyeongbyeo, respectively. As transplanting time delayed, the emerged leaf number after transplanting decreased in all rice cultivars. The cumulative temperature between transplanting time to completion of flag leaf elongation on main culm were $1,281^{\circ}C{\sim}1,650^{\circ}C$ in Unkwangbyeo, $1,344^{\circ}C{\sim}1,891^{\circ}C$ in Hwayoungbyeo and $1,454^{\circ}C{\sim}2,173^{\circ}C$ in Nampyeongbyeo, respectively. Leaf emergence rate on main culm were precisely represented by equation, y = $y_0$ + a / [1 + exp( - (x - $x_0$) / b)]^c, when we used daily mean temperature as variable.

• 한국작물학회지
• /
• 제43권3호
• /
• pp.161-167
• /
• 1998

Root and shoot development of two rice (Oryza sativa L.) cultivars with different genetic backgrounds was studied with reference to their relative growth. Tongil type (indica-japonica hybrid) cultivar 'Kuemkangbyeo' and japonica cultivar 'Koshihikari' were grown in $5000^{-1}$ a Wagnar pots under flooded condition. Three plants with roots of both cultivars were taken in every phyllochron through the heading stage to record morphological characteristics of shoot and root system. Compared to Koshihikari, Kuemkangbyeo produced more tillers and had greater shoot weight and leaf area per hill. Length and weight of the root system in both cultivars increased exponentially with time. At the same time, root system development was significantly faster in Kuemkangbyeo than in Koshihikari after the panicle initiation stage. As a result, Kuemkangbyeo has a vigorous root system which consists of larger number of nodal roots compared to Koshihikari. Also, the root length and weight per unit leaf area of Kuemkangbyeo were larger than those of Koshihikari in the later half of growing period, which suggests possible higher physiological activity of the root system of Kuemkangbyeo which is known as a high-yielding cultivar. The relationship between root traits (crown root number, total root length, and root dry weight) and shoot traits (leaf area and leaf+culm dry weight) in both cultivars closely showed allometry until the flag leaf stage.