Creation Of Potato Germplasm With Cold Resistance Via Wild Species Solanum Boliviense

Potato(Solanum tuberosum L.)as the fourth largest food crop after rice,wheat and corn,but cultivated species are sensitive to low temperature,which seriously restricts the development of potato industry.Wild species S.boliviense with cold resistance was introduced into cultivated in this study,which could provides an important germplasm to potato cold resistant breeding.The main results are as follows:Diploid cultivar ED25 with excellent synthetic properties was crossed with BLV29-2(S.boliviense)which has strong cold resistance.Ten F1 strains were obtained.F1 strains ploidy detection results showed that both of them are diploid,and tend to cultivar parents in plant growth and flowering.Cold-resistance test results indicated that F1 strains had similar freezing tolerance to sensitive parents,and much higher than that of cultivated parents in acclimated freezing tolerance,which tended to wild parents.Hence,it is speculated that freezing tolerance belongs to recessive inheritance in S.boliviense.To obtained cold resistant materials,the FT051-3 and FT051-9 of F1 strains with relatively good comprehensive traits were backcrossed with BLV37-2 and BLV29-2 respectively.Two backcross combinations were finished and named BC1.Cold resistance detection results indicated that freezing tolerance of the two BC1 was between-2.06℃ to-3.69℃ and-2.45℃ to-3.56℃ respectively.Cold acclimated freezing tolerance was obviously enhanced.Most of the strains showed super-affinity in acclimated freezing tolerance.In agronomic traits,two BC1 strains showed separation in plant shape,leaf shape,corolla shape and flower color,which could be used as an excellent population to study these traits at the same time.In order to crossing with tetraploid potato,FT073-4 was doubled by different treatment combinations.The results showed that the double treatment concentrations,time and modes all affected the survival and doubling rate of the treated materials.According to the treatment results,an efficient potato doubling technology system was established: with the treatment of 0.1% colchicine concentration 120 r/min rotational speed for 3 days.FT051-3、FT051-9、FT072-7 and FT073-4 strains with good comprehensive characters will be treated.Doubled interspecific hybrid FT073-4 has significantly enhanced in plant growth,stem thick and pollen grain size.Besides,freezing tolerance is equivalent to diploid interspecific hybrid,and significantly increased compared with the common potato cultivar.Utilizating these doubled strains to cross with the existing excellent tetraploid cultivation species.Two hybrid combinations have been obtained,a total of 293 hybrid seeds,which will be used to screening the breeding materials with cold resistance.