Study of yield, morpho-physiological, and qualitative responses of potato superelite tubersto different seed coatings

This study aims at investigating the morpho-physiological responses of potato superelite mini-tubers to different coating treatments factorial experiment, based on randomized complete block design with three replications in Research Farm of Mohaghegh Ardabili University between 2018 and 2019. Experimental factors at four levels include mini-tubers filler (zeolite and cocopeat), superphosphate (soil and pellet application), chitosan, and superabsorbent with control treatment (without pelleting). Application of cocopeat with superphosphate leads to the highest average number of tubers per plant (8.36), fresh and dry tuber yield (18.23 and 3.88 tons per hectare), and biological yield (21.69 tons per hectare). The use of chitosan in mini-tuber pelleting decrease the activity of catalase and peroxidase enzymes (19.67% and 16.37%, respectively), increasing the activity of polyphenol oxidase (37.80%). Zeolite increase and cocopeat decrease the tuber protein percentage, compared to the control. This increase in protein percentage with increasing tuber yield leads to a 32.23% increase in tuber protein yield in zeolite application, compared to control treatment. The use of superphosphate in mini-tuber pelleting also increase the protein percentage, thus leading to a 30.30% increase in protein yield, compared to control mini-tuber. In principal component analysis (PCA), the first component, with which 35% of the changes could be explained, include the yield of protein, lysine, and methionine, and the second component, with which 25% of the changes could be explained, include the protein, methionine, lysine, and total nitrogen. Finally, the results show that the mini-tuber pelleting by superphosphate, zeolite, and superabsorbent have had significant additive effects on yield and quality traits.