在江苏北部滨海盐土进行田间试验,研究了不同盐分含量土壤上盐肥耦合对菊芋生长和产量的影响。结果表明:(1)随着土壤盐分含量的增加,菊芋株高显著下降,菊芋茎粗、块茎产量和地上部生物量随土壤盐分的增加变化趋势与菊芋株高相似。随着氮肥和磷肥施用量增加,菊芋主茎高度显著增加,菊芋茎粗随氮肥施用量增加变化不明显,而块茎产量和地上部生物量随肥料用量增加变化趋势与菊芋株高相似。(2)随着施氮、磷量增加,在各盐分含量土壤上菊芋主茎普遍长高,随着土壤盐分含量的增加,氮和磷效应越明显,菊芋茎粗、块茎产量和地上部生物量在不同土壤盐分含量下,其变化趋势与菊芋主茎高度变化趋势相似。(3)各处理措施均能影响菊芋块茎产量,经方差分析,土壤盐分含量、氮肥施用量、磷肥施用量、盐肥交互作用、氮磷肥交互作用均呈极显著关系,从处理间区别看,影响菊芋块茎产量的主要因素是土壤盐分含量,氮肥和磷肥次之。其中S1N2P3处理所获得的产量最高,此处理土壤盐分含量为0.9~1.5gkg^-1,氮肥和磷肥施用量均为60kghm^-2。
A field experiment was carried out on mudflat along the coast of Yancheng, Jiangsu Province to study coupling effect of salt and fertilizer application on growth and yield of Helianthus tuberosus in soils different in salt concentration in 2008. Results show ( 1 ) the plant decreased significantly in plant height with rising salt concentration of the soils and a similar trend was observed with diameter of its stem, and yields of its tuber and shoot, and however, it displayed a reverse trend in plant height and yields of tuber and shoot, with higher N and P application, but remained almost un- changed in diameter of the stem; (2) the positive effects of N and P additions on plant height was significant in all treat- ments and became more with rising salt concentration in the soils, and so were the effects on stem diameter, and yields of tuber and shoot; and (3) variance analysis revealed extremely significant correlations at the lever of F005 and F0.01 among soil salt concentration, application rate of N and P fertilizers, interaction between salt and fertilizer application and inter- action between N and P applied. Through analysis of effects of soil salt, nitrogen and phosphorus in various treatments, the main factor that affected tuber yield was salt concentration of the soil, which was followed by fertilizers of N and P. And the yield of tuber was the highest in Treatment S1N2P3, of which the soil salt concentration was 0.9 - 1.5 g kg^-1, and the N and P application rate 60 kg hm^-2 and 60 kg hm ^-2 , respectively.