Identification Of D~2-type Cytoplasmic Male Sterile Wheat And Evaluation Of Fertility Restoration

Cytoplasmic male sterility?CMS?is a common biological phenomenon in higher plants and has important value in utilization of heterosis.In order to understand the recover ability differences of CMS wheat and restoring ability of the different recovery lines,this study used the D² cytoplasmic male sterile lines?Va706A,Ju706A,C₆706A?developed by this group as materials.By using potassium iodide staining and scanning electron microscope observation of anther and microspore,the type of abortion was determined.The K-type CMS line?K706A?was used as a control,and the three types of D² sterile lines were crossed with the 128 recovery lines selected by this group to determine the seed setting and agronomic characteristics of the F₁ generation.The similarities and differences between the three sterile lines and the K-type in fertility recovery and cytoplasmic effects were compared.The following results were obtained:1.Biological characteristics of D² male sterile wheatThe anthers of the D² and K cytoplasmic male sterile lines and the anthers of the restorer line have obvious differences in appearance and internal phenotype.The anther of the sterile line is short and curved in shape,the top of the anther is closed and non-dispersed pollen,the outer wall of the anther is disorderly,disorderly and wrinkled,unorganized,the shape of the microspores is irregular,not full,and is dry.Shape,the arrangement of ursia is sparse.The anther of the restoration line LK783 is straight and the base is split,and the outer wall is arranged clearly and regularly.The shape of the microspores is round,full and the Ubs are closely arranged.The uneven staining of pollen grains in the sterile line is not sufficient.C₆706A belongs to the classic defeat,and the shape of the pollen grains is irregular,dry and triangular.K706A,Ju706A,Va706A are either defeated or defeated.The pollen grains of the restoration line LK783 are dyed to be uniform black,and the shape is regular,the shape is full,and the shape is round.2.Screening and determination of the susceptibility of D² cytoplasmic male sterile linesThe average seed setting rate of K-type male sterile lines was higher than that of D²type cytoplasmic male sterility.Among D² type cytoplasmic male sterile line,Ju706A has the highest average seed setting rate,and the seed setting rate of crossing with 223H2 is as high as 93.67%.This is followed by Va706A,which has a seed setting rate of 91.75%after crossing with R354-1.The lowest average seed setting rate was C₆706A,but which had the highest seed setting rate with Shannong 33-1?76.97%?,and easily recovery ability was also the most stable.Thus,it can be concluded that easily restoring ability of D² type cytoplasmic male sterile line are lower than that of K type.The average seed setting rate of the D² type cytoplasmic male sterile line was Ju706A,Va706A,and C₆706A in turn,and the restoration stability was C₆706A,Va706A,and Ju706A.3.Screening and evaluation of restoration linesThrough fertility screening at different eco-location,it was found that the average seed setting rate of the restorer line 79107 to the four sterile lines,including K706A,Ju706A,Va706A,and C₆706A,was the highest in Sanyuan as well as that of Yangling,75.14%and65.02%,respectively.The recovery ability of which was relatively strong and stable.The restoring ability of the restorer lines,K460 and A731/L783,was also relatively strong,and the average seed setting rates for the four sterile lines were 72.52%and 75.51%,respectively.According to agronomic traits and fertility screening,it is concluded that the two restorer lines 79107 and A731/L783 could restore all the sterile lines,and 20 restorers could restore K706A alone,and 6 restorers could restore Va706A alone.There are 4separate restorers of Ju706A and C₆706A,respectively.