| Summary: | 碩士 === 國立中興大學 === 生命科學系所 === 101 === In this study the pollen of Brassica campestris L. subup. pekinensis and Brassica campetris L. subsp. chinensis are used for drying protocols of cryopreservation, and investigated for the effect of different water content on pollen viability with in vitro and in vivo test.
In vitro test showed the pollen of different lines treated with one hour air drying have highest pollen germination rate on B&K medium with 21% sucrose concentration. The test process removed the anther from fresh buds, and then placed it into small plastic bowl whith the diameter of 2.2 cm. The anther was then dehydrated by silica desiccant and storage in liquid nitrogen (-196°C) at least one week for cryopreservation. Afterwards, the pollen was rewarmed and then smeared on B&K medium with 21% sucrose concentration to exmine its in vitro germination rate. The result shows, after 40 ~ 60 minutes of dehydration and one week of nitrogen storage, lines of pollens produced the ability to germinate in the pollen tube. Brassica campestris L. subup. pekinensis ‘201’、’801’ and ‘Yu-Fong’ anther, which were dehydrated 80 ~ 140 min, produced a high pollen germination rate of 11.5 ~ 13.4 % while having 4.7 ~ 18.2 % water content. Brassica campetris L. subsp. chinensis ‘San-Fon’ and ‘Fon-Jan’ anther, which were dehydrated 60 ~ 100 minutes, also produced a high pollen germination rate of 7.5 ~ 11.0 %, while having 15.4 ~ 27.7 % water content. Pollens cryopreserved over one year maintain similar trends of in vivo germination rate compared with cryopreservation over one week.
On the other hand, In vivo test shows Brassica campestris L. subup. pekinensis ‘201’,’801’ and ‘Yu-Fong’ with self-pollination have highest podding rate when it has been dehydrated for 80 minutes, with the water content of 21.2, 15.2 and 23.0 %; with cross-pollination on ‘Yu-Fong’, ‘Yu-Fong’ and ‘801’, the optimization treatment was dehydrated for 100,120 and 120 minutes, with the water content of 13.1, 7.5 and 5.4 %. Brassica campetris L. subsp. chinensis ‘San-Fon’ and ‘Fon-Jan’ with the optimization treatment was dehydrated 80 and 60 minutes, with the water content of 18.2 and 27.7 %.Generally speaking, the best group of different pollen lines produces a distinctive amount of seed yield and seed germination. Pollen for dehydrated 60 ~ 100 minutes and cryoperserved for one year stilling possess both podding and seeding ability.
Based on these results, the research samples of Brassica campestris L. subup. pekinensis dehydrated 80 ~ 120 min, with the water content of 8.6 ~ 18.2 % and Brassica campetris L. subsp. chinensis dehydrated 60 ~ 80 min, with the water content of 18.3 ~ 27.7 %, both cryopreserved in liquid nitrogen for at least one week, reflects the best in vitro and in vivo germination rate. The drying protocol of cryopreservation is an effective long term storage option for Brassica campestris L. subup. pekinensis and Brassica campetris L. subsp. chinensis pollen. When combined with in vivo examination the pollen germination rate can rapidly tested. This protocol is simple to execute and carries practical usability on the breeding and germplasm conservation of Brassica campestris L. subup. pekinensis and Brassica campetris L. subsp. chinensis.
|
|---|
