Study On The Biological Character Of Blossom And The Crossability Test Of Camellia Oleifera

C.oleifera oleifera is a characteristic arboreal oil tree plant of China, Its tree body and the using value of the fruit plays an important role in living area and the construction in the forestry industry. This paper directed to the biological character of blossom and the crossability test of C.oleifera, mainly researched the flowering phenology of the main clones, the characteristics of pollens germination, the morphology of pollens, the pollens storage conditions, the Crossability of main clones, except to provide the theory in the pollens growth and in hybrid. The results were as follows.The flowering duration of populations spanned from late October to late mid-December, the flowering phenology was 80d individually, belonged "Mass-flowering" species. it was advantageous in the pollination and the pollination, but the pollination process easy to receive the climate the influence; the C.oleifera's blossom and fruit were in the same period, fruit general matured in mid-October, but not late in peak flowering phenology; the flowering phenology of same clones has differences between 2009 an 2010.Through to 2009 and 2010 flowering season cluster analysis, the C.oleifera may divide into the morning, and evening 3 kinds. The type of tries the clone flowering phenology was fixed,21,23,53, 55,88,100,297 clones belonged to the early flowering phenology,4,10,27,40,178 clones belonged to the noon flowering phenology,82,297 clones belonged to the late flowering phenology, 3,100,185,213 clones flowering phenology had the difference between 2009 an 2010.To study the characteristics of pollen germination in vitro of 6 C.oleifera species, the orthogonal test using 6 C. oleifera species as the materials was aimed to examine the effects of the 4 factors consisting of temperature, boron consumption, sucrose, and agar usage on pollen germination. The results indicated that temperature was the most significant factor of all species among the 4 factors, sucrose markedly affected the pollen germination of most species except 82 clones, and boron consumption and agar usage markedly impacted on 178 clones and 185 clones respectively.Comparing to the 4 factors impact on each test clones, the primary sequence of each factors, temperature was 25℃>18℃>12℃; sucrose was 10%>5%- 15%; the optimum of boron consumption and agar usage were 100 mg·kg-1 and 0.5%. Combining multiple comparision, the optimum extractive condition is T9:100 mg·kg-1 boron consumption +10% sucrose +0.5% agar usage+25℃temperature.To study the micro dynamic pollination and fertilization of the C.oleifera Abel, the growth of pollen on stigma were observed by optical microscope and electron microscope. The results indicated that the pollen tube percentage was significant different in different period, at the beginning the growth was slow, about the 12 hours accelerate the growth,after 22 hours the growth trend was gentle, after 24 hours the growth stopped. The whole growth of pollen tube followed the "slow-fast-slow" trent. The pollens began to germinate 0.5 hour after pollination and the pollen tubes penetrated half of the style 8 hours after pollination and reached the style base, entered the ovary after 24 hours, and the fertilization was completed about 48 hours after pollination. The whole growth of pollen tube followed the "fast-slow" trent. The germination and growth of pollen on stigma was faster significantly than that of in vitro, it could more accurately react the actual growth situations.To study on the effects of calcium (Ca2+),zinc(Zn2+)and molybdenum (Mo6+)on pollen germination percentage of 6 C.oleifera species. The results indicated that when the concentration of Ca2+ was high, the pollen germination was centration inhibited, If the concentration of Zn2+,Mo6+ was low, the pollen tube growth would be enhanced. But when the concentration of Zn2+,Mo6+ was high, the pollen germination of pollen tube was inhibited.This paper analyzed pollen viability of 6 ordinary clone C.oleifera in different storage condition as times changed. The results showed that pollen viability can be divided into 2 stages, the viability declined fast in the first 30d, then declined slower, and ended in stable. The whole process was as fast to slow to stable. In the storage, temperature was the key element, low temperature was good for viability. Moisture also affected the viability, it's good to seal the pollen in the bottle with feature of dry. The best storage condition was to seal the pollen in silica-gel drier bottle in frozen, in which the ordinary clone C.oleifera pollen could have 10% viability after 1 year.To study on the evolution status of C.oleifera in Theacea, pollens of 3 C.oleifera species were scaned by electron microscope. The results showed that the shape of pollen was mainly prolate to subsphemidal from the equatorial view, the pollen grain size were middle, sizes was 35.42～43.75μm×36.46～42.71μm;P/E was 0.83～1.11. The equatorial view was oval or ovoid, polar view was tri-lobed circular or circular, the aperture was 3-colporat containing granulats which directed along the polar axis of 120°almost stretching 2 poles, which length was 6.30～11.671μm, the colporat contained some granulats which had not the membrane or not obvious, the shape was N3P4C3. The orange surface or brain veins sculpture which indicated that C.oleifera might be primitive groups in the Theacea. There existed significant diferences in the shape and the ornamentation.Based on the natural average fruit-set rate statistical observation of main ordinary clone C.oleifera, the results showed that the average C.oleifera natural fruit-set generally was not high, fruit-bearing rate was 16.33%, and fruit-receiving rate 13.84%. Difference among clones was significant. Fruit-set clone no.40,185,53 and 4 are good, the rest even lower than the average, no. 178 and 185 full-drop ratio were lower. According to investigation of C.oleifera hybridization between the main clone, the results showed that C.oleifera of fruit-set improve cross incompatibilities was not obvious, compared to the maternal rate, the average fruit-bearing rate increased 4.41%, fruit-receiving rate only 1.90%; compared to the overall rate, the average fruit-bearing rate increased 3.57% fruit-receiving rate 1.23% only. Some specific hybrid combinations were better, the fruit-set effect of cross combinations of 185 and 81 was the best, fruit-bearing rate was 60.44% and fruit-receiving rate was 55.11%, the next is hybrid combinations of no.53 as maternal respectively with 185 and 81; the hybrid combinations of 40 and 82 was poor, need to be avoided. The results revealed that, hybridization can't significantly reduce full-drop rate.In C.oleifera clone for maternal and C.meiocarpa hybrid all could fruit-set, both of allied should belong to. fruit-set effect of hybrid combinations of 4 clone and C.meiocarpa as maternal was good, where the fruit-bearing rate of 4 x M9 was up to 30%, fruit-receiving rate 22.50%, the best fruit-set effect. The next was fruit-set effect of Hybrid combinations of 82 as one of the maternal. Compared to conventional hybrid effect of natural fruit-set effects, C.meiocarpa with C.oleifera was poorer, crossbred fluctuation easier.