Studies On Genetic Stability And Environment Influence Of Stable Carbon Isotope Of Pinus Tabulaeformis

Stable carbon isotope technology was first applied in the characteristics of specific stable carbon isotope and heritability in trees. The stable carbon isotope characteristics of Pinus tabulaeformis were studied in depth combining with the results of growth investigation, gas exchanges, climate conditions and characteristics of provenances distribution. The study was carried out in laboratory and on-farm experiments on different scales, such as one year old, eighteen years old and thirty two years old Pinus tabulaeformis, and in different conditions and levels. A series of important results were obtained and discussed relative to the characteristics of specific stable carbon isotope and heritability in trees, tree drought tolerance ecology strategy, relation betweenδ¹³C and instantaneous water use efficiency, and environmental effects onδ¹³C etc.The results showed thatδ¹³C was increasing with water status'improving. Significant seasonal changes were found in the needles'δ¹³C and in twigs'δ¹³C, which were due to precipitation and temperature, where precipitation was the dominant factors.δ13 C of one year needle's was higher thanδ13 C of two year needle's in August 2006 about 0.81‰,which showed that one year old needles had higher water use efficiency than two years old. There were significant differences in different organs and different years old Pinus tabulaeformis. The variety trends ofδ¹³C in organs wereδ¹³Cseeds>δ¹³Ctwigs>δ¹³Cneedles. The variety trends ofδ¹³C in different years old Pinus tabulaeformis were 32aï¹¥18aï¹¥1a.The differentδ¹³C in different old years Pinus tabulaeformis showed that 32a and 18a had higher water use efficiency than 1a and 32a had higher water use efficiency.δ¹³C of Pinus tabulaeformis. provenance had significant positive correlation with needle length, which perhaps might be used as the substitution index for stable carbon isotope ratio.δ¹³C of Pinus tabulaeformis. seed orchards clones had significant negative correlation with Ci/Ca and positive correlation with WUEi(r=-0.4770, r=0.5152), which showed that it could be correlated between instant water use efficiency andδ¹³C of Pinus tabulaeformis. There were higher repeatabihty or hereditary in different season and different families and different provenance. The parent offspring had high hereditary by using correlation analysis.δ¹³C of Pinus tabulaeformis.had high hereditary showed that it could be achieved better selecting effects.The correlation analysis showed that there was relationship betweenδ¹³C of Pinus tabulaeformis. province and spatial characteristics,environmental characteristics. The value ofδ¹³C increases with the increase of altitude, with significant difference. The value ofδ¹³C decreases with the increase of longitude, in whichδ¹³Ctwigs with significant difference andδ¹³Cneedles with not significant difference.δ¹³C had no significant correlation with latitude. The correlation coefficients betweenδ¹³C and Precipitation as well as warm index and seasonal aridity degree were higher than those of others environmental factors. The results were rneedles= -0.7809 and rtwigs= -0.7130, rneedles= -0.7901 and rtwigs= -0.8050, rneedles = -0.9354 and rtwigs = -0.8853, respectively. The results showed that water status and≥5℃annual accumulated temperature was the most influential factor ofδ¹³C values.