Breeding Introgression Potato Lines With Resistance To Cold-induced Sweetening And Screening For Chip Processing Lines

Potato (Solanum tuberosum L.) is the fourth-most important food crop worldwide.Cold-induced sweetening is the main reason which affects the quality of potato chipsin processing industry. Therefore, breed the potato cultivars with resistance tocold-induced sweetening has become the main objective of potato breeding. Becauseof intraspecific hybridization, the genetic backgrounds of potato cultivars’ becomenarrow gradually. Introgression breeding is a validly method to transfer the importanttraits of wild species into cultivated varieties.Eight potato introgression lines were bred from hybridization and continuousbackcrossing between the2n gametes in potato wild species and the local cultivatedpotato varieties. The progenies were screened three years depend on their fieldagronomic traits at three ecological areas. The content of reducing sugars, free aminoacids, acrylamide and activity of acid invertase were analysis after storage at roomand low temperatures and correlation analysis among chip colors and these data wereconducted to select the chip processing lines and the best wild parents. The resultswere as follows:The yield, commodity rate, the content of dry matter, starch and amylopectin ofparents of introgression lines showed the significantly different. The yield, the contentof dry matter, starch and amylopectin of primitive varieties S.phureja introgressionlines (0712-33and0722-90) were significantly higher than other wild introgressionlines, but no significantly different in commodity rate. The content of dry matter,starch and amylopectin wild S.chacoense introgression lines (0732-43and0742-66)and wild S. raphanifolium introgression lines (0725-205and0703-32) were nosignificantly different. The yield and the content of dry matter, starch and amylopectinof wild S. vernei introgression lines (0724-58and0741-7) were significantly lowerthan other introgression lines.The accumulation of reducing sugars of lines of primitive and wild species wassignificantly different after low temperature storage (4oC). The content of sugaraccumulated significantly different, and the degree of accumulation were differences in different storage conditions.There was positive correlation between the activity of acid invertase and therelative amounts of sucrose and hexose, but no strong correlation between the activityof acid invertase and the amount of hexose. There was a significant correlationbetween the contents of reducing sugars and the content of acrylamide. There were nostrong correlation between the content of free amino acids and the content acrylamideof chips. There was a great correlation between chip color and the content ofacrylamide.The Chip color was assessed by the SFA (Snack Food Association) potato chipstandard color chart. Introgression lines0712-33,0722-90,0732-43and0742-66hadlow levels of reducing sugars, acrylamide and acceptable chipping colors. The wildgermplasm resources S. phureja and S. chacoense are suitable for improving theprocessing traits of local varieties.The introgression breeding is an effective and newly potato breeding method,which transfer wild species’ processing traits into local cultivars by hybridization andcontinuous backcrossing.