Color Inheritance And AFLP And Disease Resistance Analysis Of Hybrid Progeny Of Lagerstroemia Indica L.

Lagerstroemia Indica is an important garden ornamental plants.In this study,the genetic diversity of the hybrids of tetraploid Lagerstroemia indica and its other hybrids were studied.The genetic diversity of multiple hybrids was compared and studied at the molecular level.The results showed that the activities of superoxide dismutase(SOD),soluble protein(SPR)and malondialdehyde(MDA)in leaves of Lagerstroemia indica were determined by comparing the physiological indexes of different varieties of powdery mildew,,Which provided the basis for the study of the resistance mechanism of powdery mildew and the disease resistance of the offspring of the resistant cultivars.The main findings are as follows:1.In the combination of 'Zikang 1' with 'Sihai Shengping',the color of these parent-flowers are similar,and most of the offspring showed the same appearance with parents,but also appeared in the parents of the rose red and purple;In the combination of'Zikang 2' with 'Sihai Shengping' and 'Panhe 2' with 'Sihai Shengping',there were similar colors to not only the female parent and the parent color,but alos between the two color.The same color of the offspring of the hybrid combinations showed a separation from light to deep.2.In the three cross combinations,the parental covariate bands appeared in the progeny of each combination,and also had a unique band for a single parent.The percentages of the parental specific bands were higher than those with the specific bands of the male parent,and belonged to the female parent type.The percentage of progeny specific bands of the hybrid group was higher than that of the female-specific bands,and belonged to the partial parent type.The genetic diversity values of the three combinations were H(0.209-0.2299)and I(0.345-0.3689)respectively,which indicated that the three combinations had high polymorphism and high genetic diversity.The genetic diversity of the three cross combinations was as follows: 'Panhe 2'×'Sihai Shengping'> 'Zikang 1'×'Sihai Shengping'>'Zikang 2'×'Sihai Shengping'.The clustering results show that 43 kinds of the material can be divided into three groups,in which the purple and red individuals are clustered together and the individual clusters are scattered.3.SOD activity was higher than that of the susceptible cultivars 'Zikang 1' and 'Zikang 2',and the SOD repair of the disease resistant and immunized varieties was faster than that of the susceptible cultivars.The content of MDA in the cultivars was increasing,and the content and variation trend of the resistant varieties and the varieties were similar and the changes weresmall and always lower than those of the susceptible varieties.The changes of the soluble protein content and the content of the three varieties were basically the same,the trend of.4.A total of 72 offspring were obtained,of which 19 were highly resistant to the offspring,14 were in the offspring,17 were in the progeny,22 were high,and no immune offspring were found.Through this hybrid breeding experiment,it was confirmed that the feasibility of obtaining resistance was obtained by hybrid breeding of crape myrtle.Through the comparison of multiple resistant hybrid combinations,we should give priority to 'Zikang1' as female parent in resistance breeding.