Research On Identification Technique Of Predominantly Male And Female Pinus Koraiensis

Korean pine is one of the most important industrial timber species in northeast China,and its roots,stems,leaves,flowers and fruits have good economy value. Korean pine has male and female flowers on the same tree.When the plants reach to sexual maturation, the ratio of male flowers to female flowers reaches equilibrium in the whole forest. Due to the difference of site condition, illumination and genetic factor, there are significant differences both individual fruit setting amount and the ration of female and male flowers in the same stand. Referring to the methods ofВ.Н.ВОРОБВЕВandЕ.В.ТИТОВ, the samples are selected relating to the typical morphology characteristics. The study is intended to analyse the sexual types of Korean Pine, so as to choose the suitable proportion between predominatedly male and female plants in production and management.In this paper, the identification technique in predominantly male and female plants of Korean Pine was studied .By analyzing autumn morphology data, observing the percentage of pollen germination in predominantly male and female plants at different mediums, contrasting the difference of dyeing colors by chemical reagents such as methyl red, BTB and TTC in needles, measuring the content of water soluble phenolic substances by tartaric acid-Fe spectrophotometry, analyzing the endogenous hormones content of tender stem by enzyme linked immunoassay, the difference between predominantly male and female plants in germination rate , the change of dyeing colors ,the content of the phenolics substances and the endogenous hormones was detected. The results were as follow:(1)The difference of percentage of pollen germination in predominantly male and female plants at CK, 10% sucrose and 20% sucrose were significant, and the variance analysis at 30ppm and 50ppm boric acid with 10% sucrose showed that the difference was also significant.(2) The needles of predominantly male and female plants were treated respectively with chemical reagent. The color of the extract from predominantly female plants changed lighter than that from predominantly male plants after 3 hour reaction with methyl red. There was also a significant difference between predominantly male and female plants at 400-730nm with BBT. The colors of the extract from predominantly male and female plants were not changed when TTC was added into the extract and the difference of absorbed light volume from predominantly male and female plants were not significant. Therefore, both methyl red and BTB methods were more suitable to be applied to identify predominantly male and female plants.(3)The variance analysis for the content of water soluble phenolic substances in pre -dominantly male and female needles showed that the difference was not significant,and can not be taken for sex identification.(4) The difference of the content for IAA, GA and ZR between predominantly male and female plant was significant not only in different ages but also in different seasons. But the difference of the content of ABA was significant only at 25 years old.Sexual of Korean Pine could be determined by the difference of the percentage of pollen germination at different sugar and boric acid concentration, the color of the extract with methyl red and BBT, the total contents of IAA, GA and ZR.Determination of these differences laid a foundation of further study on the selection of excellent stand and plus tree.