Plant Type and Dry Matter Production in Peanut (Arachis hypogaea L.) Cultivars
II. Varietal differences in radiation interception
ABOAGYE Lawrence Misa, Akihiro ISODA, Hiroshi NOJIMA, Yasuo TAKASAKI, Takao YOSHIMURA** and Toshio ISHIKAWA** (Faculty of Horticulture, Chiba University, Matsudo-city, Chiba 2 7l, Japan ; **Remote Sensing and Image Research Center, Chiba University, Inage-ku, Chiba-city, Chiba 263, Japan)
Abstract : Eight peanut cultivars of the Virginia types (Chibahandachi and Chiba 43) , Spanish type (Kintoki) , Valencia types (Valencia, Tarapoto and Hotakuchuryu) and the types derived by crossing Virginia with Spanish types (Kanto 56 and Tachimasari) were investigated under field conditions to clarify the relationship between the canopy structure, its components and solar radiation interception. The Virginia types were of short stature, smaller leaflet areas, higher leaf area indices (LAI) , greater leaf numbers and intercepted lower radiation per leaflet area. The Spanish and Valencia types were tall, had greater leaflet areas, lower leaflet numbers and greater intercepted radiation per leaflet area. The crossing types were of medium or low plant heights, leaflet area and LAI. Generally, the mean leaflet intercepted radiation was higher at each layer of the canopy in the taller cultivars and lower in the shorter cultivars. Kanto 56 was exceptional, with its lower plant height, medium leaflet size and LAI ; and intercepted greater amount of solar radiation.
Key words : Canopy structure, Integrated solarimeter films, Peanut, Plant type, Radiation interception.