Study On The Relationship Of Chromosome Lectin Of Some Species Of Leguminous Trees With Nodulation

As we all know, not of all leguminous trees can fix nitrogen. It's important in theories and uses to study on why some species of leguminous trees can not be nodulated. This study can bring the theories base of making un-nodulated legume trees be able to nodulate., as well as be favor to the study on the relationship of rhizobia with their hosts .The study is on the reasons why some species of leguminous trees can not be nodulated on the trees' chromosome and lectin. The main result are as follow:1. 3 species of leguminous trees in Mimosoideae are nodulated,4 species of leguminous trees in Papilionoidae are nodulated, Sophorajaponica in Papilionoidae is un-nodulated,9 species of leguminous trees in Caeselpinioideae aren't nodulated.The color of the nodulated leguminous trees'roots is lighter from light yellow to yellow than that of un-nodulated leguminous trees from light brown to black.2. According to the counting the chromosome numbers of 18 species of leguminous trees, the number of chromosome of leguminous trees has relation with whether the leguminous trees are nodulated or not in some degree.The chromosome numbers of 10 species of un-nodulated leguminous trees which expect for Cassia occidentalis are all 28 which is divided intergrally by 7. The chromosome numbers of Cassia occidentalis is 26.and un-nodulated. Each of the chromosome number of 9 species of leguminous trees which can be nodulated is not 28 and is not divided intergrally by 7. These chromosome numbers all are not divided intergrally by 7.3. All of the chromosome of 18 species of leguminous trees are diploid, but because of the function of the pretreatment, there are few cells that have tetraploid chromosome in roots squash of leguminous trees.4. Karyotype analysis indicate that caryotype formula of Sophora davidii is K (2n) =2x=18=14m (8SAT)+4sm. Karyotype formula of Cassia canymbosa is K (2n) =2x=28m(4SAT) . Cassia canymbosa is more original than Sophora davidii.5. The reaction of lectins with rhizobium is the pre- condition of founding the relationship of symbionic nitrogen fixation. Some leguminous trees can recognize rhizobium but still can not be nodulated.