Study On Sediment Of Purple Pigments And Inheritance Of Purple Character In Purple Wheats (Triticum Aestivum L.)

It is well known that the pigment of wheat is one of the important aspects that determine its quality,so it's of great significance to study the pigment of wheat. Useing purple kernel wheats as materials(plateau115,Longchun4324,etc.),combining the way of field trials with detecting in laboratory,this paper studied the light effects on the pigment contents and the dynamic changes of the contents of chlorophyll,carotenoid, anthocyanin and melanin.Furthere,the pigment's inheritance rule of purple kernel wheat by sexual hybrids with each other was studied so as to discuss the rule of the dynamic of pigment accumulations in purple kernel wheat,enrich the theory of wheat breeding and offer theory and technical support in pigment wheat breeding and industrialization.The main research contents and results are as follows.Using shade on spike treatment,the paper studied the content change of chlorophyll, carotenoid,anthocyanin and melanin with different light time and photoperiod in purple and red kernel wheat in different grain developing stages.The results showed that there was no relation between chlorophyll and carotenoid's contents and photoperiods. However,the formation and accumulation of anthocyanin and melanin had close relationship with light time.From 25 days after flowering,light time affected the formation of anthocyanin and melanin directly.When treated late lighting,the contents of anthocyanin and Melanin were 1.78 and 2.03 times respectively higher than those of prophase lighting.Purple kernel wheat and red kernel wheat showed different responses to light time.With the increase of light time,the contents of chlorophyll and carotenoid had increasing trends,but different varieties had no significant differences.Anthocyanin and melanin contents increased quickly with the light time increase,but different varieties showed extremely significant differences.From 15days after flowering,detecting the dynamic of pigment accumulation of different wheat seeds,the results showed that:(1)the content of anthocyanin in wheat seed was less in prophase,subsequently it increased graduately.The anthocyanin accumulation in purple kernel wheat was much quick than that of in red kernel.With the seed developing, the content of anthocyanin in wheat seed increased.And anthocyanin could be detected when 15 days after flowering and reached the peak when 30 days after flowering,then decreased.At various developing phases,the darkener of the seed,the higher content of anthocyanin,i.e.purple kernel＞lilac kernel＞red kernel.Anthocyanin couldn't be detected in white seed variety,Longchun23,in different developing phases.(2)The content of carotenoid was very low in seed developing prophase and increased graduately with the developing of seed.Although the change trends of the carotenoid were similar between purple kernel wheat and lilac kernel wheat,the amounts were distinctly different.Melanin couldn't be detected in different developing phases in white seed variety,Longchun23.(3) In seed development,the chlorophyll content was in extremely significant positive correlation with carotenoid,but in a negative correlation with anthocyanin and extremely significant negative correlation with melanin.The correlations between carotenoid and anthocyanin,melanin were silimar to those of chlorophyll.Anthocyanin and melanin had positive correlation.3.Analyzing the genetic character of purple kernel wheat variety—plateau115 and longchun 4324 which were selected by different methods,the results showed that:(1)No matter how plateau115 and non-purple kernel varities reciprocal cross,F₂ seeds were all purple kernels,the proportion of purple kernels and non-purple kernels was 9:7,and that of BC₁(F₁×non-purple kernel)was 1:3.The seeds of BC₂(F₁×purple kernel)were all purple kernels.Therefore,it could be thought that the character of purple kernel-plateau115 was controlled by two pairs of dominant genes which are complementary genes.(2)No matter how Longchun4324 and red seed varieties(Longchun15)and white seed variety(Longchun23)reciprocal cross,F₂ seeds were all purple kernels.Using Longchun4324 as agnate crossed back,BC_{1 seeds}were all purple kernels.Using non-purple kemels(Longchun15 and Longchun23)as agnates cross back,the proportion of purple kernels and non-purple kernels in BC₂ seeds were 1:1.x2 test indicated that the proportion of separate of F₃ purple kernels and non-purple kernels followed the proportion of 3:1.So,it could be concluded that the relative character of purple kernels of Longchun4324 was controlled by a pairs of complete dominate genes.4.Simple sequence repeats(SSR)were employed to detect molecular markers linked to purple wheat gene in new spring wheat variety Longchun4324 which was bred by Gansu Academy of Agricultural Science.The purple was controlled by single dominant gene.A SSR marker Xgwm16 was proved to link to the purple gene.This purple gene has been located in 5DS and the sequence in 5DS was:Left 5'—Gct tgg act agc tag agt atc ata —3',right 5'—Caa tct tca art ctg tcg cac gg—3'.5.Using purple kernel wheat and non-purple kernel wheat as materials,adopting incomplete dialel cross method,the paper studied the cordinate abilities among the quality traits,such as content of protein and wet glutin,sedimentation,development time,stability time,of purple kernel,and those of yield of spike,including ear length,spiklet number, grain number per spike,1000 grain weight and single grain weight.The results showed that there were more differences in GCA effecting values in the same quality traits but different parents of purple kernel wheats.There were significant differences in GCA effecting values in the same spike traits among different parents of purple kernel wheats.Analyzing 16 combinations,melanin kernel wheat 76×Longchun23 had higher SCA effect not only quality traits but yield traits,so it should be selected as an important combination.