Development of DRIS norms for potato in the calcareous soils of Iran
1993
Navvabzdeh, M. | Malakouti, M.J.
The Diagnosis and Recommendation Integrated System (DRIS) has been proposed to determine nutrient balance in plants at different stages of growth. The DRIS index for each nutrient allows ranking of nutrients in order of their deficiency. Preliminary DRIS norms for potato (Solanum tuberosum L.) were developed during the 1991 growing season in Damavand area located 70 km northeast of Tehran. The soil and leaf samples at flowering stage (early tuber development stage) were collected from 50 different farms. Average concentrations of nutrients in both high- and low-yielding populations were calculated. The following average foliar nutrient concentration were obtained from the high-yielding populations: N = 5.22, P = 0.38, K = 4.20, Ca = 1.50, and Mg = 0.65 percent; and Fe = 150, Mn = 50, Zn = 40, Cu = 11, and B = 38 ppm. The average nutrient concentrations for the low-yielding population were close to those in high-yielding ones except for K which was 3.23 in contrast to 4.20-percent. There was no significant relationship between different soil nutrient availability indices and yield except for K. The DRIS indices ranked K as the most limiting nutrient in the low yielding farms with only one exception. It seems high rates of N and P fertilization have created a lack of balance between these nutrients and K.
显示更多 [+] 显示较少 [-]