Although Brassica juncea (Indian mustard) is reported to be a good accumulator of metals, little is known of the selected varieties of B. juncea (cvs. Rai and BARI-11). This paper investigates the phytoaccumulation of...Although Brassica juncea (Indian mustard) is reported to be a good accumulator of metals, little is known of the selected varieties of B. juncea (cvs. Rai and BARI-11). This paper investigates the phytoaccumulation of arsenic, cadmium and lead by B. juncea (cvs. Rai and BARI-11) parents and F1 hybrids. The experiment was conducted in the hydroponic media in the greenhouse of University of Southampton under a Randomised Block Design. Sodium arsenite, cadmium sulphate and lead nitrate with 0 ppm, 0.5 ppm and 1 ppm were used. The cadmium treated plants were analysed by Varian Atomic absorption spectrophotometer-200. The samples of arsenic and lead were analysed by Inductively Coupled Plasma Atomic Emission Spectrophotometer. The results suggest that arsenic was detected only in the root systems while cadmium and lead were detected both in the root and shoot systems. Significant differences in the uptake were observed for different concentrations. Accumulation of arsenic was detected only in the root systems of B. juncea (cvs. Rai and BARI-11) at lower concentrations. Hence, this can be used as an agriculturally viable and efficient phytoaccumulator in the arsenic affected areas where contamination level is low and the contamination occurs at the rooting level.展开更多
Anthocyanins confer the wide range of colors for plants and also play beneficial health roles as potentially protective factors against heart disease and cancer. Brassica juncea is cultivated as an edible oil resource...Anthocyanins confer the wide range of colors for plants and also play beneficial health roles as potentially protective factors against heart disease and cancer. Brassica juncea is cultivated as an edible oil resource and vegetable crop worldwide, thus elucidating the anthocyanin biosynthetic pathway would be helpful to improve the nutritional quality of Brassica juncea through the breeding and cultivating of high anthocyanin content varieties. Herein, 129 genes in B. juncea were identified as orthologs of 41 anthocyanin biosynthetic genes(ABGs) in Arabidopsis thaliana by comparative genomic analyses. The B. juncea ABGs have expanded by whole genome triplication and subsequent allopolyploidizatoin, but lost mainly during the whole genome triplication between B. rapa/B. nigra and A. thaliana, rather than the allopolyploidization process between B. juncea and B. rapa/B. nigra, leading to different copy numbers retention of A. thaliana homologous genes. Although the overall expansion levels ABGs were similar to the whole genome, more negative regulatory genes were retained in the anthocyanin biosynthesis regulatory system. Transcriptional analysis of B. juncea with different anthocyanin accumulation showed that BjDFR, BjTT19, BjTT8 are significantly up-regulated in plants with purple leaves as compared with green leaves. The overexpression of BjTT8 and these target genes which were involved in late anthocyanin biosynthesis and transport might account for increasing levels of anthocyanin accumulation in purple leaves. Our results could promote the understanding of the genetic mechanism of anthocyanin biosynthesis in B. juncea.展开更多
文摘Although Brassica juncea (Indian mustard) is reported to be a good accumulator of metals, little is known of the selected varieties of B. juncea (cvs. Rai and BARI-11). This paper investigates the phytoaccumulation of arsenic, cadmium and lead by B. juncea (cvs. Rai and BARI-11) parents and F1 hybrids. The experiment was conducted in the hydroponic media in the greenhouse of University of Southampton under a Randomised Block Design. Sodium arsenite, cadmium sulphate and lead nitrate with 0 ppm, 0.5 ppm and 1 ppm were used. The cadmium treated plants were analysed by Varian Atomic absorption spectrophotometer-200. The samples of arsenic and lead were analysed by Inductively Coupled Plasma Atomic Emission Spectrophotometer. The results suggest that arsenic was detected only in the root systems while cadmium and lead were detected both in the root and shoot systems. Significant differences in the uptake were observed for different concentrations. Accumulation of arsenic was detected only in the root systems of B. juncea (cvs. Rai and BARI-11) at lower concentrations. Hence, this can be used as an agriculturally viable and efficient phytoaccumulator in the arsenic affected areas where contamination level is low and the contamination occurs at the rooting level.
基金funded by the National Key Research and Development Program of China(2016YFD0100202)the Natural Science Foundation of Hunan Province,China(2016JJ1010)the Scientific Research Fund of Hunan Provincial Education Department,China(18C0305,17K035,17C0652,and 17C0653)。
文摘Anthocyanins confer the wide range of colors for plants and also play beneficial health roles as potentially protective factors against heart disease and cancer. Brassica juncea is cultivated as an edible oil resource and vegetable crop worldwide, thus elucidating the anthocyanin biosynthetic pathway would be helpful to improve the nutritional quality of Brassica juncea through the breeding and cultivating of high anthocyanin content varieties. Herein, 129 genes in B. juncea were identified as orthologs of 41 anthocyanin biosynthetic genes(ABGs) in Arabidopsis thaliana by comparative genomic analyses. The B. juncea ABGs have expanded by whole genome triplication and subsequent allopolyploidizatoin, but lost mainly during the whole genome triplication between B. rapa/B. nigra and A. thaliana, rather than the allopolyploidization process between B. juncea and B. rapa/B. nigra, leading to different copy numbers retention of A. thaliana homologous genes. Although the overall expansion levels ABGs were similar to the whole genome, more negative regulatory genes were retained in the anthocyanin biosynthesis regulatory system. Transcriptional analysis of B. juncea with different anthocyanin accumulation showed that BjDFR, BjTT19, BjTT8 are significantly up-regulated in plants with purple leaves as compared with green leaves. The overexpression of BjTT8 and these target genes which were involved in late anthocyanin biosynthesis and transport might account for increasing levels of anthocyanin accumulation in purple leaves. Our results could promote the understanding of the genetic mechanism of anthocyanin biosynthesis in B. juncea.
