The early prognosis of tuber yield based on nitrogen status in potato tops

• Published in: Plant, soil and environment Vol. 64; no. 11; pp. 539 - 545
• Main Authors: GRZEBISZ, Witold, POTARZYCKI, Jarosław, BIBER, Maria
• Format: Journal Article
• Language: English
• Published: Prague Czech Academy of Agricultural Sciences (CAAS) 01-01-2018; Czech Academy of Agricultural Sciences
• Subjects: Field tests; Nitrogen; nitrogen management; nutrient content; Nutrients; Phosphorus; Potassium; Potatoes; solanum tuberosum l., tuberous crop; Vegetables; Water shortages; Zinc
• ISSN: 1214-1178; 1805-9368
• DOI: 10.17221/388/2018-PSE

The pattern of nitrogen net change (ΔN) in potato tops during the period extending from BBCH 33 to BBCH 40 is crucial for tuber yield (TY). This hypothesis was verified based on data from field experiments (2006–2008) with sequentially added nutrients (0, NP, NPK, NPKS, NPKSMg) to potato. The water shortage in June/July 2006 and in June 2008 significantly affected N content, and in turn TY. The TY was reduced by 38% in 2006 and by 23% in 2008, as compared to 2007 (53.7 t/ha). The N content in potato tops at BBCH 40 of 2.5% indicated the lowest TY, whereas 4.3% the maximum TY. The ΔN of +0.4% within the period from BBCH 33 to BBCH 40 determined the optimal range of the N content for the maximum TY (3.9–4.3%). The ΔN trend depended on the change of phosphorus and potassium contents. The key reason of N inefficiency was the shortage of potassium (K), resulting in its negligible change within this period. The pattern of zinc content at BBCH 40 reflected fairly well disturbances in N as well as K supply to potato. A good supply of K and Zn to potato can improve N management just before tuber initiation.