Phenotypic and molecular-genotypic correlation of diseases resistance in improved varieties potato (Solanum tuberosum L.)

Abstract

In two consecutive agricultural campaigns (2010-2011 and 2011-2012), 18 improved potato varieties were planted in the PROINPA Foundation greenhouses as well as two witness varieties (Waych’a and Desirée) with the aim to study: i) late blight resistance (Phytophthora infestans), wart (Synchytrium endobioticum) an virus PVX and ii) validate molecular markers GP94, RB, CP60 and NL25 for co-localizing with major resistance genes of diseases mentioned. The results showed significant differences among varieties for AUDPCrel (late blight), severity (Wart) and severity and absorbance (PVX). Different levels of resistance were observed in varieties, such varieties with high resistance and moderate resistance. Molecular analysis were highly significant to Pr<0.01 of probability for three of the market used. It was observed that the allele for marker GP94 was co-located with the resistance gene Rpi-phu1 for late blight at a distance of 350 bp, showing the resistance allele in all varieties except the Waych'a variety. The allele for RB marker that is co-localizes with the RB gene for resistance to blight was not found in any of the varieties tested. The allele for marker CP60 was co-located with Rx1 gene to PVX resistance at a distance of 350 bp and it was observed in almost all varieties except Chota Ñawi variety. Finally, the allele for marker NL25 is co-located with Sen1 gene resistance to wart at a distance of 1000 bp and it was observed in all varieties.

Keywords

• potato wart
• PVX virus
• severity
• absorbance
• inoculum