Selection And Characterization Of The New Strains In Porphyra Haitanensis Chang Et Zheng(Bangiales, Rhodophyta)

Three new blades of Porphyra haitanensis Chang et Zheng wasobtained with application of the mutagenesis, the somatic cells’regenaration of the gametophytic blade, and the selectivity breeding.These new strains were named as B-102, D-1and XS-2, respectively. Andtheir homozygous conchocelis were get by parthenogenesis. B-102strainwas selected from the blade of the thin-thallus strain B-101which hadobtained in our lab after several consecutive regeneration and selection ofsomatic cells. In the same way, D-1strain was selected from the blade ofD-0which was collected from the cultivation ground, and XS-2strain wasselected from the blade of XS-1which was selected in our lab like B-101.Faster growing, higher contents of phycobiliprotein, thinnerthickness of the blades and later maturation characterize B-102ascompared with B-101and the wild type (WT) strain. After60days ofculture under the same conditions, the mean length of F1gametophyticblades of B-102grew up to360cm, and the gametophytic blades ofB-101grew up to61.1cm when it is only13.5cm to WT. There were five peaks in the in vivo absorption spectra of B-102, B-101and WT bladesbetween wavelengths of350-750nm, and the five peak values of B-102were higher than that of B-101and WT. The phycobiliprotein content ofB-102was89.83mg/g, increased by6.7%and177.3%than B-101andWT, respectively. The mean Chl.a content of B-102was8.62mg/g, whichwas higher than that of B-101(8.43mg/g) and WT (6.71mg/g). The meanthickness of B-102blades was18.33μm, which was13.8%and42.6%thinner than that of B-101and WT, respectively. The F1gametophyticblades of B-102did not mature even being cultured more than85days,meanwhile a few of the blades of B-101and WT strated to mature whencultured40days and50days, respectively. Faster growing, highercontents of phycobiliprotein, thinner thickness of the blades and latermaturation characterize D-1as compared with the unimproved baldes ofD-0and WT strain too. After70days of culture under the same conditions,the mean length of F1gametophytic blades of D-1grew up to209.4cm,and the blades of B-101grew up to65cm when it is only18.65cm to WT.There were five peaks in the in vivo absorption spectra of D-1, D-0andWT blades between wavelengths of350-750nm, and the five peak valuesof D-1were higher than that of D-0and WT. The phycobiliproteincontent of D-1was143.00mg/g, while the content of D-0is77.97mg/g,and that of WT is only27.87mg/g. The mean Chl.a content of D-1was11.00mg/g, highly higher than that of D-0(6.69mg/g) and WT (6.71mg/g). The mean thickness of D-1blades was21.51μm, which was39.6%and32.6%thinner than that of D-0and WT, respectively. But the blades ofD-1strain had no clear advantage in mature compared with D-0and WTstrain. The new strain XS-2had higher contents of phycobiliprotein andthinner thickness of the blades compared with the XS-1and WT strain.The phycobiliprotein content of XS-2was116.12mg/g, while the contentof XS-1is84.18mg/g. The mean Chl.a content of XS-2(9.69mg/g) wasalso higher than that of XS-1(8.42mg/g) and WT (6.71mg/g). There werefive peaks in the in vivo absorption spectra of XS-2, XS-1and WT bladesbetween wavelengths of350-750nm, and the peak value of XS-2in P3was higher than that of XS-1and WT. The mean thickness of XS-2bladeswas20.83μm, highly higher than that of XS-1(27.53μm), while thethickness of WT strain is31.91μm. The F1gametophytic blades of XS-2were growing faster than XS-1and WT strain obviously after cultured lessthan55d. After cultured more than55d, the blades of XS-2had a slowergrowth rate than XS-2because of germ cells dropped off the blades whichcaused the mean length of XS-2blades Shortened. XS-2blades were easyto mature that was like the WT strain. Taking together, B-102and D-1strain had a faster growth rate, higher contents of phycobiliprotein andthinner thickness of blades, that mean they may offer broad applicationsfor the nori industry. XS-2strain had higher contents of phycobiliproteinand thinner thickness of the blades, but its growth period was not long enough and it matured early, the mechanism of that needs a furtherresearch. XS-2strains can be used as the basis materials of genetic andbreeding studies.