Vp. Ila'Ava et al., Response of sweet potato cultivars to acid soil infertility factors. II. Effects of calcium supply and soluble aluminium on early growth, AUST J AGR, 51(1), 1999, pp. 29-36
Good growth in acid soils suggests that sweet potato may be tolerant of aci
d soil infertility factors such as Al toxicity or Ca deficiency. In a conve
ntional solution culture experiment, 4 cultivars responded positively when
solution Ca concentration was increased from approximately 4 to square M Ho
wever, a subsequent flowing solution culture (FSC) experiment showed no sig
nificant (P > 0.05) differences in growth by most of the 15 cultivars studi
ed when solution Ca concentration was increased from 45 to 400 square M Hen
ce, it was concluded that sweet potato could be fairly tolerant of low Ca s
upply. In contrast, soluble Al markedly decreased growth of the 15 sweet po
tato cultivars studied. The results of the present study indicate that Al r
ather than low Ca supply would be more important in limiting sweet potato g
rowth in acid soils. Furthermore, tolerance to low Ca and soluble Al appear
s to be linked in sweet potato. These results highlight the importance of s
electing sweet potato cultivars for specific soil conditions such as soil a
cidity.