Influence of N fertilization and irrigation on potato yield and starch contents in 2003 and 2004.

摘要

Influence of irrigation and N fertilizer level on yield and starch contents of potatoes was studied over 2 yr using potato var. Karlena in 2003 and var. Carmona in 2004. Potatoes were cultivated at 1 of 2 locations in each year (with or without sprinkler irrigation) using N fertilizer applications of 0 (control), 120, 160 or 200 kg N/ha. Increasing N fertilizer dose unexpectedly increased starch contents of non-irrigated potatoes by 0.35-0.65% in 2003 compared with control. Starch contents in irrigated potatoes in 2003 decreased with increasing N concn. from 18.15% in control to 16.30% for the 200 kg N/ha treatment. Control potatoes in 2004 had higher starch contents than those receiving N application for both irrigated and non-irrigated treatments. High soil quality at 1 location was believed to contribute to the high starch contents in potatoes grown at this site.