Cytogenetical Studies Of Celery And Other Umbelliferae Vegetables

In this study, we did cytogenetical studies of five umbelliferae vegetables inclouding celery conventional pressed slice methed. The main results are as following:1.The celery was used chromosome technique study, various factors were studied including drawing materials, pre-treatment, fixation, pre-hypotonic treatment, dissociation, post-hypotonic treatment. The results revealed that the optimal procedure for celery was:to excise growing root tips at about9:30when they were about5mm in length and pretreated in0.002mol·L-18-hydroxyquinoline for2.5h. Treated root tips were then fixed in an ethanol:acetic acid (3:1) solution for24-28h. Subsequently, pre-hypotoniced in0.075mol·L-1KC1for20-30min and dissociated in1mol·L-1HCl(60℃)for8.5min. Finally, post-hypotoniced in distilled water for8min.The flower buds of celery were used for chromosome technique study, various factors were studied including drawing materials, fixation, dissociation. The results revealed that the optimal chromosome technique procedure was:At first flowering dates, to selected flower buds whose length was1-1.5mm, fixed in an ethanol:acetic acid (3:1) solution for24-28h; dissociated in1mol·L-1HC1(6O℃) for6min; post-hypotoniced in distilled water for8min; selected overy tissue for squash.2.The flower buds and root tips of celery were used,the meiosis in pollen mother cells and mitosis in root tips were studied with chromosome sectioning, the results showed that:The pollen mother cells carried on theirmeiosis and cytokinesis simultaneously and their tetradswere tetrahedral or decussate types;at metaphases Ⅰ and Ⅱ there showed a small number of chromosomes scattered outside their equatorial plate; at anaphases Ⅰ and Ⅱ there appeared chromosome bridges and lagged chromosomes in some pollenmother cells;The interphase and all the four phases of mitosis including prophase, metaphase, anaphase and telophase were well observed. Atmetaphase, the chromosomes condensed to the minimum, thus this phase was optimal for observing and studying chromosomes.3.Using the flower buds and the root tips,the karyotype of Apium graveolens L. during meiosis diakinesis in pollen mother cells and mitotic metaphase were studied, and the best way to obtain the diakinesis chromosomes was disscussed. the results are the same:the karyotype formula of Apium graveolens L. was K(2n)=2x=22=6m+2sm+8st+6t, both of them had3pairs of metacentric chromosomes(5,7,9),1pair of submetacentric chromosomes (6),4pairs of with acrocentric chromosomes(2,3,8,11) and3pairs of telocentric chromosomes(1,4,10). Relative length from2n=2S+2M1+6M2+1L, belonging to3B type.4.The karyotype of five main umbelliferous vegetables and karyotype comparison were studied by traditional squash method. The results showed that, Apium graveolens L.:K(2n)=2x=:22=6m+2sm+8st+6t,belonging to3B type; Coriandrum sativum L.:K(2n)=2x=22=2m+2sm+18st,belonging to3A type; Foeniculum vulgar-e Miller: K(2n)=2x=22=14m+6sm+2st, belonging to2B type; Oenanthe stolonifera DC. K(2n)=2x=22=6m+6sm+10st,belonging to3A type; Daucus carota L. K(2n)=2x=18=6m+10sm+2st,belonging to2A type.We discussed the genetic relationship and genetic diversity of umbelliferous vegetables.