Effect of substrate on potato minitubers production in greenhouse using <i>in vitro</i> plants

Abstract

The use of organic and inorganic substrate has not been completely developed in Cuba for biotechnological potato seed production using in vitro plant. In order to define a suitable substrate for the production of potato minitubers in greenhouse this research was conducted, for which five formulations with casting and zeolite were used. The response of growth and development of potato plants cv. `Desiree' obtained through in vitro culture was determined. The treatments consist of the following formulations: 1) 100% Casting, 2) 85% Casting + 15% Zeolite, 3) 70% Casting + 30% Zeolite, 4) 55% Casting + 45% Zeolite, 5) 100% Zeolite. Physiological indexes: Net Assimilation Rate (NAR), Relative Growth Rate (RGR) and Absolute Growth Rate (AGR) were determined in three stages of the crop: 0, 15, 30 and 45 days after plantation. The number of mini-tubers and the average weight of tubers were determined at 90 days. The response to the growth and performance of minitubers weight per plant and the quality of tubers over 45 g was higher in the 100% Casting substrate and substrate combination 85% Casting + 15% Zeolite. The best results in the number of tubers per plant were achieved with formulations of 100% zeolite substrates, 55% Casting and 45% Zeolite, without significant deference to the formulation of 70% Casting and 30% Zeolite. Keywords: Casting, growth, physiological indexes, yield, zeolite