Response of potato (Solanum tuberosum cv. Agria) to seed inoculation with mycorrhiza strains in different phosphorus fertilization

摘要

In order to study effect of seed inoculation with mycorrhiza strains at different rates of chemical phosphorus fertilization on potato yield a factorial field experiment was conducted during 2010-2011 at Research Station of Islamic Azad University, Ardabil Branch, Iran. Studied factors were mycorrhiza strains (Glomus intraradices and G. mosseae) and phosphorus fertilization including 33%, 67% and 100% of recommended dose of triple superphosphate. The means of the treatments were compared using the least significant difference test. Results revealed that interaction of mycorrhiza strains and phosphorus fertilization on crop leaf chlorophyll content index at early flowering stage was significant. Inoculation of potato tubers with G. mosseae in combination with application of 67% of superphosphate recommended dose resulted in increasing of chlorophyll content up to 78.2. Number of tubers smaller than 30 g was reduced when potato seeds were inoculated with G. intraradices or G. mosseae and lower than recommended dose of superphosphate was applied. Greater number of tubers, weighing 80-280 g, was obtained with application of 67% of recommended phosphorus dose. Mean comparisons indicated that in non-inoculated potato tuber yield increased with increasing phosphorus rate and the highest yield (30.8 t ha-1) was obtained from full dose phosphorus application. In potato treated with mycorrhiza the highest tuber yield (44.2 t ha-1) allocated to 67% phosphorus recommended dose × G. mosseae, which had 196% increase compared to control. Seed inoculation with mycorrhiza can play a major role in reducing chemical phosphorus fertilization rate in sustainable production systems of potato.