The Study On The Radiation Induced Mutation Of Privet Seeds And Mutant Selecting

Privet is a deciduous shrub, which belongs to the Oleaceae famaily.Because it has many branches, shear resistance, neat and beautiful,it is widely used as a hedge in garden. Because of its rich flower and pleasant aroma, it is used as clumped plants in garden.The radiation breeding as an important breeding method is always taken by the breeding workers. 60Co radiation can enhance the rate of mutation, promote gene recombination and the successful hybridization of distant strain. Using the RAPD can detect the variation degree of the genome mutation in the molecular level. It also can appraise and choose the mutations of radiation descendant early through the anaysis on relativity between the genome variation degree and radiation dose, enhance the breeding efficiency. So it has important theory and practice significance.This experiment confirmed the suitable radiation dose of the privet germinating seeds through privet seeds in connection with 60Co-γinduced mutation, analyzed the production ways and variation character of the M1 generation and the relativity between the radiation dose and coefficient of variation of the M1 generation through the RAPD. The primary content and result are as follows:(1)The order Of sensitivity of Radiation plant material: Germinating seed> Wet seed>dry seed,because of radiation sensitivity of Germinating seeds is the strongest, Germinating seeds finally are used as the experimental material.(2)From budding rate of privet, the semi-lethal of the privet germinating seed (LD50) is about 50Gy. From survived rate of privet, the semi-lethal is about 45Gy. It is not suitable the largest radiating dose surpasses 200Gy. The experimental result indicated that radioactive seeds have budding but should not grow in to plants when the radiation dose surpasses 200Gy.(3)After privet germinating seeds are radiated, the production ways of variated branch and variated plant of seedlings were mainly four kinds: Plants grow to a certain extent, happened the top single-branch and trunk of health; A plant come into being several together branches; At the bottom of plant has much branch, the side normal leaves and anther side twist leaves; On trunk of a plant have a lot of Alternate branches .(4)The variated branch and plant mainly represented in shape of leaf and trunk. The variation of leaf type show asymmetric leaves, twist, tip concave, double-vein and so on. Plant variation show plants dwarf, internodes short, several together branches and so on; So as the radiation dose increase, the height of plants gradually reduce. This illustrate the size of radiation dose has inhibition action to plant height.(5)Between chlorophyll and radiation dose emerge negative correlation.With the increase of radiation dose, the content of chlorophyll gradually reduce. With the increase of radiation dose, SOD, POD activity increase then lower.(6)Radiation has some influence to plant stomatal morphology. Through the electron microscope M1 generation plants stomatal morphology show the M1 generation leaf stomatal pores larger than contrasted plant leaf.(7)The radiation dose had an extremely positive relativity with variation coefficient of the M1 generation. We can appraise and choose the mutations of radiated descendant early in the molecular level using the method of RAPD, enhance the breeding efficiency.