Alnus Fomosana Aneuploid Screening And ISSR Analysis

Alnus formosana, belongs to Betulaceae family and Alnus Mill, also known as alder. It is a deciduous trees species originated in Taiwan province and an important pioneer affeorestation tree. At present, the study of Alnus formosana focuses on introduction, adaptability, ecology, seeding cultivation, fine asexual selection, biological nitrogen fixation and nuclear morphometry analysis. However, the research about polyploidy of Alnus formosana has not been developed basically. This experiment, we screened aneuploid plant through chromosome counting of root rip of Alnus formosana seeds by the method of wall-degradation and flame-drying. Then the Alnus formosana seed was treated with colchicine to induce polyploid. At last, we have obtained aneuploid plants through counting chromosome of apex of tender leaf, and the ISSR was used to analyse the genome of aneuploid plant. The results showed as follow:1.3960 alnus formosana seeds as experimental meterial, chromosomal counting was carried out with their root tips by wall degradation hypotonic flame-drying method. The result indicated there was obvious variety in chromosome number of Alnus formosana, which was 2n=14,28,42,56, and between 14-112. Even the chromosome number in different cell of the same root were not identity. We obtained 110 aneuploid plants, and the occurrence frequency of chromosome number being integral multiples of 7 were respectively 0.101%(2n=14),0.025%(2n=21),0.151%(2n=28), 0.075%(2n=35),0.328%(2n=42),0.227%(2n=49),0.025%(2n=63). Moreover,2.78% of plants were aneuploidy, the plant with 112 chromosomes was not discovered.2.At the same time, we found that multinuclear and amitosis phenomenon occurred in root tip cells of Alnus formosana.3.The chromosome counting of apex of first leaves were carried out with 51 of annual Alnus formosana, of which 7 are aneuploid, respectively 1 (2n=51).2 (2n=52),19 (2n=42),21 (2n=54),24 (2n=50),25 (2n=56,112),30 (2n=52).4.The ISSR was taken to analyse the aneuploid then used UPGMA cluster to analyse the data of 1SSR. The results showed that aneuploid plants were divided into 3 categories, the first class was 1, the second class was 2,4,5, the third class was 3,6,7. The ISSR results indicated that the aneuploids of Alnus formosana have a characteristic of genetic variation.