Assessment of potato microtuber and in vitro plantlet seed multiplication in field conditions – Growth, development and yield

Abstract

Microtubers and in vitro plantlets are the basic materials of potato seed production. Minitubers are yield of tubers derived from the first generation of in vitro plantlets or from microtubers. At present the production of minitubers usually takes place under covers – in glasshouse, plastic tunnels and screenhouses. The aim of this research was to assess the possibility of carrying out such multiplications in field conditions. The growth, development and harvesting was estimated in in vitro plantlets, microtubers, minitubers and traditional seed potatoes. Additionally, three terms of in vitro plantlets and microtubers planting in the field were assessed (1st term – second week of April, 2nd term – fourth week of April, 3rd term – last week of June/first week of July). The weather conditions in 2006–2012 impacted greatly on the survival of in vitro plantlets and microtubers planted in a field, especially in the 1st and 3rd terms. In spite of clear differences in the size of planted seed material, the highest reproduction coefficient per one plant was recorded for traditional seed potatoes and microtubers, and the lowest for minitubers. While at the 1st and 2nd terms of planting the average number of tubers from one plant ranged between 6.7 and 8.8, at the 3rd term this value oscillated between 11.2 and 12.4. Analysis of the productivity of particular seed material clearly indicates a much higher share of potentially useful tubers derived from microtubers and in vitro plantlets than of traditional seed potatoes or minitubers. Microtubers and in vitro plantlets planted earlier (1st term of planting) or significantly later (3rd term) produced the greatest minituber yield. Because of a high risk connected with the dying out of plants and maintaining adequate coverage at its earlier planting, the 3rd term of planting of this material was much more favorable. At the same extreme weather conditions (drought and lack of rainfall at the beginning of after planting), which occurred in 2010 contributed to a very strong reduction plants in the field.