Heretable Pleiotropic Effects Of Glabrous And Saucer Shape Gene Loci From Peach

Diversification of fruit types is peach breeding trends. Peaches have a wide diversity of fruit types according to looking,only one gene G/g,(pubescence/glabrous)or S/s( saucer shape/ nonsaucer) different exists between a peach and a nectarine, between a flat and a peach , they form 4 types together by looking, peach , nectarine, flat peach and flat-nectarine. 496 peach cultivars , 481 seedlings of 10 families, or some samples of them were compared in their quality , yield index , fruit development, cell structure and inclusion to identify the heretable pleiotropic effects of glabrous and saucer shape gene from PeachThe results were as follows:(1)According to cultivar groups, comparing peach and flat peach, nectarine and flat-nectarine, the results showed that saucer shapes had higher SSC, higher soluble sugar contents, but lower titratable acid contents, firmness without skin, average fruit weight and yield index. Comparing peach and nectarine, flat peach and flat-nectarine, glabrous characteristics, cultivars had higher SSC, titratable acid contents, flesh degree, firmness without skin, but lower soluble sugar contents, fruit average weight and yield index. Comparing peach and flat-nectarine, flat-nectarine SSC and soluble sugar contents were higher and lower titratable acid contents, fruit average weight and yield index.(2) According to family groups,both glabrous gene and saucer shape decreased significantly average fruit weight. Decreasing effect could be accumulated when glabrous and saucer shape existed together, but they had no mutual effects. Average fruit weight of nectarine was decreased by 16.79%, flat peach 39.04%, flat-nectarine 46.34%. Glabrous gene and saucer shape increased significantly SSC. Increasing effect could be accumulated when glabrous and saucer shape existed together, but they had no mutual effects. SSC of nectarine was increased by 11.20%, flat peach 19.05%, flat-nectarine 27.64%. Both glabrous gene and saucer shape could increase sugar content , the increasing effect was significant when glabrous and saucer shape existed together. The changing regulation of sucrose, glucose and fructose contents were not found to be influenced by glabrous gene and saucer shape gene, but peach relative glucose content was higher than flat-nectarine significantly .Glabrous gene could increases titratable acid contents(P=0.1). (3) The fruit pattern of peach,nectarine,flat and flat-nectarine were seen as double sigmoid curves vertical diameter, cross diameter , suturn diameter,fruit weight,fruit volume,fresh flesh weight and dry flesh weight. The vertical diameter of saucer shape fruit undergone a slower growth rapid than nonsaucer duringⅠandⅢperiods; During whole growth periods, the vertical of flat peach was 60% of peach, and flat-peach was 50% of nectarine. The dry pit of peach and nectarine had a rapid growth duringⅡperiod.The out epidermis cells were 1～4 layers for peach and flat, and only one for nectarine and flat nectarine, pubescence gene influenced on the number of epidermis cell layer. There were thick cuticle at out wall of epidermis for nectarine and flat-nectarine, especially flat-nectarine. Glabrous gene made epidermis higher thickness/ width.The shapes of sub-epidermis were round for peach and flat, but rectangle for nectarine and flat-nectarine, the width was bigger than thickness. There were much many starch granule at sub-epidermis cell for flat-nectarine, and many for nectarine and flat peach, but nothing for peach. The starch granuled of flat nectarine had formed 22d after full bloom for flat nectarine, 29d for nectarine and for 50d for flat peach.During fruit develop period, mesocarp of nectarine was the smallest among 4 types. By the end ofⅡperiod, the average size of mesocarp cells were respectively peach, flat-nectarine, flat and nectarine from big to small size. By the end ofⅡperiod,the cell size of sub-epidermis for peach ,flat, nectarine and nectarine and flat-nectarine were respectively 1190μm2,936μm2,907μm2,624μm2, the cell size of mesocarp respectively 5931μm2,4071μm2,3342μm2,4539μm2, the cell size of epidermis respectively558μm2,563μm2,738μm2,1044μm2. There were no significant correlation between the cell size and fruit average weight.The ultra-structure of the development of fruit dots: epidermis and sub-epidermis cells were filled with dark substance, the wall of cells were twisted and formed stomatic cells; stomatic cells wall became thick and phellem and then fruit speckle formed. The results showed that plasmodesmata exist at parenchyma cells under epidermis cells, a great deal of starch-typed plastids are present around plasmodesmata.The starch content, soluble sugar content and titratable acid contents of near epidermis cell were higher than inside.