Study On The Color Evaluation Technology Of Ornamental Crabapple Cultivar Group

The color, pigment component and pigment content in 77 varieties of ornamental crabapple was studied. Obtained a comprehensive and accurate color evaluation system. The main results were as follows:1) The color system of crabapple. The three color systems of crabapple flower were white, pink and purple. These varieties could be divided into six groups. The two color systems of Crabapple leaf were green and brown. According to various index sign of crabapple leaf color in spring, these varieties could be divided into four groups. According to various index sign of crabapple leaf color in summer, these varieties could be divided into three groups.The lightness, chroma and chromatic component of crabapple petals and young leaves significantly different between Crabapple varieties.2) the pigment component in the petals and leaves of crabapple. The three pigments in the petals of crabapple were anthocyanin, carotinoid and chlorophyll. The main pigment was anthocyanin. There were four anthoeyanins in petals of crabapple, which were Delphinidin-3-glucoside, Cy-3-glucoside, Cy-3-malonyglucoside and Pelargonidin-3-rutinoside. The kinds of anthocyanin were different in the petals of different colors. The three pigments in the leaves of crabapple were anthocyanin, carotinoid and chlorophyll. There were four anthoeyanins in leaves of crabapple, which were Delphinidin-3-monoglucoside, Cy-3-glucoside, Cy-3-malonyglucoside and Cy-3- propionylglucoside. The kinds of anthocyanin were different in the leaves of different colors.3) According pigment content and spectral value, curvilinear equations were fitted. The three curvilinear equations of pigment content in crabapple petals were:anthocyanin y=0.014x+0.0012(R2=0.9974), carotinoid y=0.0038x0.3772(R2=0.9902), chlorophyll y=-0.1007x2 +0.3221x-0.2169(R2=0.8179). The first two equations had high fitting degree and high accuracy, so they could be used in practice. But chlorophyll equation was too imprecise to be used in practice. The three curvilinear equations of pigment content in crabapple leaves were:carotinoid y=0.0001x2+ 0.0046x+0.1633(R2=0.9901); anthocyanin y=0.008x+ 0.0062(R2=0.9943); chlorophyll y=0.0264x2-0.2073x+1.0271(R2=0.9828), These equations had high fitting degree and high accuracy, so they could be used in practice.4) The key enzyme of anthocyanin biosynthesis Activity of CHI and anthocyanin content in petals of crabapple were positively correlated. CHI might be the key enzyme of anthocyanin biosynthesis. PAL was not the key enzyme of anthocyanin biosynthesis.5) The mechanism of color fading. Because of the differences of anthocyanidin synthase activity between different varieties, the fading degree and speed of petals were different. For example, the fading degree of M.'Roudph'and M.'Pink Spires'were large, but the fading degree of M.'Abundunce' and M.'Purple Royalty' were very small. Due to changes of anthocyanidin synthase activity, the degradation rate and oxidation rate of the anthocyanin changed, the kinds and contents of the anthocyanin decreased. So the fading phenomenon of petals happened.6) The qualitative and quantitative analysis were carried out on the color and pigment by RHS, Lab, spectrometry and HPLC-ESI-MS. Forming a complete color evaluation system of ornamental crabapple cultivar group.