Effect of separate pod and root zone temperatures on yield and seed composition of three Spanish cultivars of groundnut (Arachis hypogaea L)

The effect of separate pod and root temperature regimes (all four combinati ons of 28/22 and 40/34 degreesC day/night temperature), imposed from the ti me of peg penetration until harvest, on yield and seed composition of three Spanish genotypes of groundnut (Arachis hypogaea L) was investigated. A de crease in pod temperature from 40/34 to 28/22 degreesC increased yield and oil, starch and protein mass per plant irrespective of root temperature. Ad ditionally, a reduction in pod temperature decreased protein concentration and increased the sum of oil and starch concentration at a root temperature of 28/22 degreesC, whereas at a root temperature of 40/34 C a decrease in pod temperature increased protein concentration. Root temperature reduction diminished oil concentration of genotypes AH 6179 and TMV 2 at a pod tempe rature of 40/34 degreesC. A decline in pod temperature affected fatty acid composition through a decrease in palmitic acid irrespective of root temper ature and an increase in linoleic acid at a root temperature of 28/22 degre esC. A root temperature effect on fatty acid composition was not detected. It is concluded that field management practices and choice of genotype can influence groundnut yield and seed composition through effects on pod and r oot temperature. (C) 2001 Society of Chemical Industry.