Comparative Study On Diversity Of Planktonic Algae In The Paddy Field Planting Conventional Rice With Bt Rice

In order to understand the diversity of planktonic algae in paddy field,the field experiment was carried out for three consecutive years in Xiangtan Experimental Base,Hunan Province.The diversity of phytoplankton community in conventional paddy field and transgenic Bt rice paddy field were analyzed.The diversity of planktonic algae communities in conventional paddy field was compared with the diversity of planktonic algae in transgenic Bt rice paddy field.The main results are as follows:1.The algae community in the conventional rice paddy field is mainly composed of Bacillariophyta,Chlorophyta,Cyanobacteria,Gyeongho,Dinophyta and Cryptophyta.A total of 149 planktonic algaes pecies belonging to 6 phyla and 69 genera were collected in 2012,among which there were 19 species of Cyanobacteria 8 genera,59 species of Chlorophyta 32 genera,55 species of Bacillariophyta 22 genera,11 species of Gyeongho 4 genera,3 species of Dinophyta 2 genera,and 2 species of Cryptophyta 1 genera.A total of 159 planktonic algaes pecies belonging to 5 phyla and 69 genera were collected in 2013,among which there were 24 species of Cyanobacteria 12 genera,66 species of Chlorophyta 29 genera,55 species of Bacillariophyta 22 genera,12 species of Gyeongho 4 genera,2 species of Dinophyta 2genera.A total of 154 planktonic algaes pecies belonging to 6 phyla and 70 genera were collected in 2014,among which there were 18 species of Cyanobacteria 11 genera,65 species of Chlorophyta 29 genera,54 species of Bacillariophyta 21 genera,12 species of Gyeongho 4genera,3 species of Dinophyta 3 genera,and 2 species of Cryptophyta 2 genera.There was no significant change in the species composition of planktonic algae in three years,and the abundance of planktonic algae was maintained at a high level.The individual volume ranged from 303.1 to 502.7,the diversity index ranged from 3.98 to 4.40,the homogeneity index ranged from 0.833 to 0.905,and the dominant concentration index was between 0.0178 and0.0249.The conventional rice paddy field water is poor nutrition type and clean water body and community stability is high.2.The algae community in the Bt rice paddy field is mainly composed of Chlorophyta,Bacillariophyta,Cyanobacteria,Gyeongho,Dinophyta、Cryptophyta and Chrysophyta.A total of 147 planktonic algaes pecies belonging to 7 phyla and 68 genera were collected in 2012,among which there were 15 species of Cyanobacteria 8 genera,56 species of Chlorophyta 29 genera,61 species of Bacillariophyta 23 genera,10 species of Gyeongho 4 genera,2 species of Dinophyta 1 genera,and 1 species of Cryptophyta 1 genera.A total of 156 planktonic algaes pecies belonging to 7 phyla and 72 genera were collected in 2013,among which there were 16 species of Cyanobacteria 10 genera,69 species of Chlorophyta 31 genera,56 species of Bacillariophyta 20 genera,12 species of Gyeongho 4 genera,2 species of Dinophyta 1genera,and 1 species of Cryptophyta 1 genera.A total of 156 planktonic algaes pecies belonging to 6 phyla and 70 genera were collected in 2014,among which there were 17 species of Cyanobacteria 11 genera,66 species of Chlorophyta 30 genera,56 species of Bacillariophyta 22 genera,12 species of Gyeongho 4 genera,3 species of Dinophyta 3 genera,1 species of Cryptophyta 1 genera,and 1 species of Chrysophyta 1 genera.There was no significant change in the species composition of planktonic algae in three years,,and the abundance of planktonic algae was maintained at a high level.The individual volume ranged from 301.1 to 488.5,the diversity index ranged from 4.16 to 4.46,the homogeneity index ranged from 0.831 to 0.904,and the dominant concentration index was between 0.0171 and0.0238.Bt rice field water is poor nutrition type and clean water body and community stability is high.3.The similarity of the phytoplankton community and dominant species sub-community in the two habitats was high.In 2012,a total of 149 planktonic algaes pecies belonging to 8 phyla and 65 genera were collected in conventional rice paddy field and a total of 147 planktonic algaes pecies belonging to 7 phyla and 68 genera were collected in Bt rice field,and 142 species of planktonic algae in both habitats,the similarity of species composition of planktonic algae in two habitats was 0.9595,and 17 dominant species in both habitats,the similarity of dominant species is 0.5862.In 2013,a total of 159 planktonic algaes pecies belonging to 6 phyla and 69 genera were collected in conventional rice paddy field and a total of 156 planktonic algaes pecies belonging to 6 phyla and 67 genera were collected in Bt rice field,and 146 species of planktonic algae in both habitats,the similarity of species composition of planktonic algae in two habitats was 0.9270,and 17 dominant species in both habitats,the similarity of dominant species is 0.5231.In 2014,a total of 154 planktonic algaes pecies belonging to 7 phyla and 72 genera were collected in conventional rice paddy field and a total of 156 planktonic algaes pecies belonging to 7 phyla and 72 genera were collected in Bt rice field,and 152 species of planktonic algae in both habitats,the similarity of species composition of planktonic algae in two habitats was 0.9806,and 18 dominant species in both habitats,the similarity of dominant species is 0.6923.There were no significant differences in the species richness,the individual volume,the Shannon-Winner diversity index,the uniformity index,and dominant concentration index between the two habitats,and the trend of dynamic change with time was basically the same.There was no significant difference in the community diversity of planktonic algae in Bt rice habitat and conventional rice habitat.