Study On Mutual Recognition And Preservation In Vitro Of Pollens And Stigmas Of Cabbage With Self-incompatibility

Experiments about conservation systems, identification methods and mutual recognition were made with pollens and stigmas of cabbage material I which has self-incompatibility. In this study.plant tissue culture > physiological and biochemical technique were put into the experiments.Then we have acquired the objective conservation systems for pollens and stigmas. The results are the following:Fresh pollens on the blossoming day and buds blossoming in a day were collected respectively in the period of vigorous flowering cabbage, then stigmas were peeled from buds at the condition of asepsis.Pollens were preserved at low and ultro-low temperature,while stigmas wre conserved at low temperature.The germination and dyeing rate of pollen collected by electric machine were equal to that of pollen collected by hand. So pollen could be collected by electric machine instead of by hand. There were many factors influenced the pollen conservation. When the water of pollen was 9.93% to 14.18% by dehydration ,the result was the best.Howerer,when the pollen was dehydrated excessively(2.07%) or not dehydrated at all(30.49%),the result was poor. And the pollen preserved at 4癈 could maintain vigour for only approximate one month.As the preservation time passed ,the germination rate of pollen conservated at -20 癈 or -70 癈 cut down ,although the methods could lengthen time than that at 4癈.But the germination rate of cabbage pollen preserved at -196癈 for 6 months was 36.40% which was about 2 percent higher than that of fresh pollen.It indicated that there was cold stumilating to cabbage pollen conserved at -196癈. It was able to improve the effect of pollen preservation if pre-colded especially at -20 癈 before conservation.At the same time, the germination rate was 38.17%, 1.79% higher than that of pollen unpre-colded.And the method of thawing was another factor affecting pollen conservation. When pollen was thawed at room temperature ^ in hot water and resuscitated slowly,the germination rates respectively were 32.13%, 36.37%, 28.70%.It indicated that the germination rate increased throngh thawing in hot water.As a result,it was a ideal means of thawing.There were many methods to identificate the activation of cabbage stigma preservated at low temperature.When stigma was conserved at culture medium 2 (5mg/LABA+20g/L mannitol) or 6 (5mg/LABA+ 30g/Lmannitol) for 3 to 6 months ,from the color and form feature et al,we could know that the stigma was light green and didn't inflate ,and that thedyeing rate of the stigmatic epidermal cells was higher than 90%,all those were not obviously different from fresh stigma.However,the form and feature of stigma preserved at other culture mediums changed at different degree. With tissue culture identificating the activity of stigmas in culture medium 2 and 6, the rates of inducing stigma callus tissue respectively were 79.53?