Characteristics of Radiation Interception and Photosynthesis of Japanese and Chinese High-Yielding Peanut Cultivars under Dense Planting

Teihua Cao and Akihiro Isoda

Abstract: Japanese (Kanto 83, Nakateyutaka) and Chinese (Huayu 16, Luhua 11) high-yielding peanut cultivars were densely planted to analyze their yield abilities in terms of characteristics of intercepted radiation and photosynthesis. The Japanese cultivars had short plant height with a large leaf area in the upper 2 or 3 layers from the top of the canopy (5~15cm). The Chinese cultivars had tall plant height with a small leaf area in each layer. The canopy of Chinese cultivars intercepted a larger amount of radiation than that of Japanese cultivars, due to higher values of intercepted radiation per unit leaf area despite smaller leaf area index. In particular, Huayu 16 intercepted a large amount of radiation per unit leaf area in each layer than the other cultivars. Kanto 83 had the smallest light extinction coefficient mainly due to the small leaflet size, despite the dense leaf distribution. The CO2 assimilation rate and quantum yield of photosystem II in the later growing season were large in Kanto 83 and Huayu 16, which showed higher seed yields. Huayu 16 had effective characteristics for radiation interception, allowing it to maintain a high radiation use efficiency later in the growing season.
Key words: Arachis hypogaea L., Canopy structure, CO2 assimilation rate, Dense planting, Peanut, Quantum yield of photosystem II, Radiation interception.