LOSS OF ORGANIC COMPOUNDS FROM ROOTS .I. CULTURAL CONDITIONS FOR AXENIC GROWTH OF PEANUT, ARACHIS-HYPOGAEA, L

Nutritional factors, temperature and pH were investigated for their effects on embryo germination and seedling growth of axenic peanuts. Optimum temperature range for seedling growth was between 32°C and 35°C and pH optimum was between 6 and 7. Sucrose, gibberellin and either (NH4)2SO4 or KNO3 as nitrogen sources increased seedling growth. When a mixture of thiamin (0.01 ppm), riboflavin (0.1 ppm) and 2,4-D (0.01 ppm) was added to the nutrient medium dry weight and height of the seedlings was increased as much as 50 per cent. Plants were successfully grown from axenic embryos separated from the cotyledons to mature plants which produced axenic seed in plastic isolator chambers, but growth was delayed compared to plants developing from seed. Axenic seed was planted under sterile conditions and a second generation of axenic plants obtained which produced viable seed. © 1969 Martinus Nijhoff.