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Abstract [Objectives] The effects of "Glimmer" treatment on dry matter accumulation， yield and cadmium accumulation in different types of rice varieties were investigated， in order to provide a theoretical basis for the regulation of low cadmium accumulation in rice grains.
[Methods] Under the treatment of cadmium contaminated soil with a concentration of 0.58 mg/kg， the effects of "Glimmer" treatment on dry matter accumulation， yield and cadmium content of different rice varieties were studied by pot experiment.
[Results] Spraying "Glimmer" can increase the biological yield of rice， and the different types of rice showed the order of conventional rice>twoline hybrid rice>threeline hybrid rice. Among the conventional rice， most significant increase was observed in Huanghuazhan， and in twoline hybrid rice， C Liangyou 651 increased the most. The "Glimmer" treatment had an obvious yield increasing effect on conventional rice， among which such two varieties as Xiangwanxian 13 and Huanghuazhan had the largest increases， followed by the twoline hybrid rice， and a little effect was observed on the threeline hybrid rice. The "Glimmer" treatment resulted in a significant reduction in cadmium content in different types of rice， which decreased by 13.33%-26.09%， and seven varieties showed a reduction over 21.74%.
[Conclusions] The "Glimmer" treatment can significantly reduce the cadmium content in rice， and generally promote the dry matter accumulation and yield increase of rice， of which conventional rice performed better.
Key words Glimmer; Rice; Cadmium absorption; Yield
Rice is the second largest food crop in China. Nearly twothirds of the countrys population live on rice. Therefore， rice quality and safety are directly related to national health and social stability. Heavy metal cadmium is a nonessential growth element of crops， which is easily absorbed and enriched by crops in the soil and eventually endangers human health through the food chain. A large number of scholars have carried out more exploration and practice on the control of cadmium pollution， mainly aboutthe biochar remediation method， the application of soil acidification conditioner to improve the soil pH value， the method of replacing topsoil with guest soil， phytoremediation and other methods[1-3]. Phytoremediation technology is considered to be the main means of soil remediation at this stage[4]. Some studies have found that there are big differences in cadmium enrichment ability between rice varieties[5-10]， and the accumulation of cadmium in the grains of the same variety is greatly affected by soil cadmium changes[11-13]. "Glimmer" is a natural organic polymer compound， the main component of which is humic acid. Studies have shown that the use of humic acid to improve heavy metal contaminated soil can achieve a better remediation effect[14-15]. At present， there are few reports on the application of "Glimmer" foliar application to regulate the accumulation of cadmium in rice grains. In view of this， in this study， "Glimmer" was sprayed on the leaves and panicles of 12 different genotypes of rice during grain formation， and the effects of "Glimmer" treatment on dry matter accumulation， yield and cadmium accumulation in different types of rice varieties were analyzed， aiming at providing a theoretical basis for the regulation of low cadmium accumulation in rice grains. Materials and Methods
Experimental materials
Twelve rice varieties cultivated in large area and being popularized were selected， including four conventional rice varieties， namely Huanghuazhan， Xiangwanxian 13， Xiangwanxian 16 and Nongxiang 18， four twoline hybrid rice varieties， namely C Liangyou 651， Y Liangyou 3218， Fengliangyou 4 and Zhunliangyou 527， and four threeline hybrid rice varieties， namely， Shenyou 9588， Tianyou 998， Chuanxiang 8 and Nei 5 You 263.
Experimental methods
The 12 varieties were sprayed with "Glimmer" to serves as the "Glimmer" treatments， with spraying clear water as control. "Glimmer"humic acid was applied at 200 ml/667 m2， once at rupturing stage and once at heading stage. The rice was planted in plastic pots， which had a surface area of about 0.16 m2 （diameter： 45 cm）. Each pot contained 15 kg of cadmium contaminated soil （taken from the polluted farmland soil in the tin mine area of Lengshuijiang City）. The soil was airdried， finely sieved and repeatedly stirred， until the soil cadmium content was uniform. Rice was planted according to 3 holes per pot， 2 plants per hole. The splitplot experiment design was adopted with three replicates （four pots per variety）. After pregermination of rice varieties， the rice seedlings were first raised in Cdfree rice field. After 30 d， the seedlings were transplanted into the pots. After transplanting， a 2-3 cm water layer was maintained on the soil surface during the whole growth period.
Cultivation management： The pure water produced by the pure water equipment was used for irrigation， and the soil was flooded by 1-4 cm water during the whole growth period （that is， 4 cm water was introduced after transplanting， and when the water level naturally decreased to 1 cm， water was supplemented to 4 cm then）. The fertilizing amount was calculated according to the soil area. Specifically， 180 kg of pure nitrogen was applied per hectare under N∶P∶K=1∶0.5∶0.8. In the base fertilizer， N， P and K accounted for 50%， 100% and 40% of the total， respectively， and 50%， 0% and 60% of the total amounts were applied as the tillering fertilizer. The fertilizers were fully dissolved， and the nutrient solution was quantitatively applied into the pots to ensure that the amount of fertilizer applied to every pot was the same.
Analysis of dry weight and yield： Representative plants were divided into roots， stems， leaves and panicles （seeds）. After drying at 105 ℃， the different parts were dried at 80 ℃ to constant weight. The yield was determined after airdrying the seeds at maturation stage. Determination of heavy metal cadmium： Soil and rice samples were digested by MARS microwave digestion system （manufactured by CEM， USA）， and cadmium content was determined by inductively coupled plasma atomic emission spectroscopy （ICPAES）.
Data processing
The data were processed and analyzed using DPS and Excel software.
Results and Analysis
Effects of "Glimmer" on dry matter accumulation in different rice varieties
From the perspective of rice type， spraying "Glimmer" can slightly increase the biological yield of rice compared with spraying water （control）， and the increase order was conventional rice>twoline hybrid rice>threeline hybrid rice. Among the conventional rice， most significant increase was observed in Huanghuazhan， of which the total dry matter quantity was 43.90 and 55.35 g/plant at heading and maturation stages， respectively， which increased by 11.56% and 32.04% compared with the control， respectively. As to the twoline hybrid rice， C Liangyou 651 increased the most， and its total dry matter quantity was 41.52 and 51.46 g/plant at heading and maturation stages， respectively， which increased by 4.19% and 9.10% compared with the control， respectively. Analyzing from different parts of rice plants， spraying "Glimmer" can increase the dry weight of roots at heading stage and the dry matter quantities of roots， leaves and grains at maturation stages， but had no significant effect on the dry matter quantity of stems （Table 1）. It indicated that the application of "Glimmer" can increase the dry matter quantity of conventional rice Huanghuazhan， mainly the dry matter quantity of the roots and the weight of leaves at maturation stage， thereby increasing root absorption and leaf photosynthesis， and finally， its dry matter increased significantly at maturation stage.
Effects of "Glimmer" on yield and yield structure of different rice varieties
Table 2 shows the effects of "Glimmer" on the yield and yield structure of different genotypes of rice. As can be seen from Table 2， the rice varieties treated with "Glimmer" increased yield by 28%-36%， of which the yield of threeline hybrid rice was increased by 36%， and that of conventional rice was increased by 28%. The plant height， panicle length， number of grains per panicle， number of panicles， seed setting rate and 1 000grain weight were increased to certain extents after treatment. Meanwhile， it can be seen that there were certain differences between different rice varieties. The 1 000grain weight varied from 16.8 to 25.7 g. Among the difference varieties， such four varieties as Chuanxiang 8， Zhunliangyou 527， Nongxiang 18 and Nei 5 You 263 all had a 1 000grainweight over 25 g， while the two varieties， Huanghuazhan and Xiangwanxian 16， both exhibited a yield below 20 g. By comparing and analyzing these traits， it was found that the number of grains per panicle of C Liangyou 651 was 270 grains/panicle， Shenyou 9588 had the most effective panicles （12.43 panicles/plant）， and Nongxiang 18 exhibited the largest 1 000grain weight （26.8 g）. "Glimmer" has a higher yielding potential for conventional rice varieties such as Xiangwanxian 13 and Huanghuazhan. Jing ZHOU et al. Study on the Effect of "Glimmer" on Cadmium Absorption and Yield of Rice
Effects of "Glimmer" on cadmium content in different rice varieties
It can be seen from Table 3 that the accumulation of cadmium in different genotypes of rice after spraying "Glimmer" at heading stage was reduced to a certain extent， and the reductions were in the range of 13.33%-26.09%. Among the different types of rice， the conventional rice， twoline hybrid rice and threeline hybrid rice showed an average reduction of 20.03%， 22.11% and 19.80%， respectively. There were seven rice varieties of different genotypes exhibited a reduction over 21.74% after sprayed with "Glimmer"， namely， Nongxiang 18， Fengliangyou 4， C Liangyou 651， Nei 5 You 263， Zhunliangyou 527， Xiangwanxian 13 and Tianyou 998， and only 2 varieties showed a reduction less than 15.00%（Xiangwanxian 16 and Y Liangyou 3218）. This indicated that "Glimmer" had a little effect on the cadmium contents in different types of rice， but a greater impact on different genotypes of rice.
Conclusions and Discussion
The results of this study showed that the dry matter quantities in different types of rice increased after spraying "Glimmer"， and the increasing rule was that the increases of roots， panicles and total amount were significantly larger than those of stems， leaves and grains， i.e.， root>panicle>stem>leaf>grains. Different genotypes of rice increased in different degrees， which were expressed as conventional rice>twoline hybrid rice>threeline hybrid rice variety， and maturation stage>heading stage. It was also found that the conventional rice varieties and twoline hybrid rice varieties had higher yield increasing potential than threeline hybrid rice varieties. After the treatment with "Glimmer"， rice yield can be increased by 28%-36%， among which the yield increase of threeline hybrid rice yield was 36%， and that of conventional rice was 28%. The plant height， panicle length， number of grains per panicle， number of panicles， seed setting rate and 1 000grain weight increased to different degrees after treatment. Meanwhile， the accumulation of cadmium in different types of rice was significantly reduced after spraying "Glimmer" at heading stage， with a reduction of 13.33%-26.09%. There were no significant differencesin cadmium content between different types of rice， but the application of "Glimmer" treatment had a great effect on different genotypes of rice. Specifically， such seven varieties as Nongxiang 18， Fengliangyou 4， C Liangyou 651， Nei 5 You 263， Zhunliangyou 527， Xiangwanxian 13 and Tianyou 998 decreased more significantly. The results of this study were obtained by analyzing the effects of "Glimmer" on cadmium content， yield and dry matter accumulation in different types of rice cultivars under the conditions of planting rice cultivars in the potted soil contaminated with cadmiumat a low concentration of 0.58 mg/kg. Because the pot experiment had a certain influence on the growth and development of rice， the experimental results have yet to be further verified under the conditions of field cultivation. In addition， pot experiments can be carried out under moderate cadmiumcontaminated （1.0 mg/kg）and high cadmiumcontaminated （2.0 mg/kg） soil to further explore the effects of spraying "Glimmer" on yield， cadmium content and their change laws in different types of rice varieties， in order to better understand the impact of "Glimmer" on different genotypes of rice and provide a reference for largearea applications in field.
References
[1] SUN XJ. Study on the characteristics and treatment of heavy metal pollution in soil[J]. China Resources Comprehensive Utilization， 2018， 36（4）： 144-145，151. （in Chinese）
[2] LI XT， GU ST， ZHENG WJ， et al. Research progress on remediation technology of heavy metal contaminated soil[J]. Environmental Science & Technology， 2013， 36（S2）： 203-208. （in Chinese）
[3] GU JG， ZHOU QX. Cleaning up through phytoremediation： A review of Cd contaminated soils[J]. Ecological Science， 2002， 21（4）： 352-356. （in Chinese）
[4] MCGRATH SP， ZHAO J， LOMBI E. Phytoremediation of metals， metalloids， and radionuclides[J]. Advances in Agronomy， 2002， 75： 1-56. （in Chinese）
[5] ZHANG BJ， LUO GL， WEI YH， et al. Dynamic difference analysis of cadmium accumulation in different genotypes of rice[J]. Chinese Agricultural Science Bulletin， 2015， 31（9）： 25-30. （in Chinese）
[6] LI KQ， LIU JG， LU XL， et al. Uptake and distribution of cadmium in different rice cultivars[J]. Journal of AgroEnvironment Science， 2003， 22（5）： 529-532. （in Chinese）
[7] ZHANG XZ， ZHANG HJ， LI TX， et al. Differences in Cdtolerance of rice and screening for Cd lowaccumulation rice germplasm resources[J]. Chinese Journal of EcoAgriculture， 2013， 21（11）： 1434-1440. （in Chinese）
[8] CAI QL， LIN DS， WANG G， et al. Differences in cadmium accumulation and transfer capacity among different types of rice cultivars[J]. Journal of AgroEnvironment Science， 2016， 35（6）： 1028-1033. （in Chinese）
[9] LONG XL， XIANG XC， XU YF， et al. Absorption， transfer and distribution of Cd in indica and japonica rice under Cd Stress[J]. Chinese Journal of Rice Science， 2014， 28（2）： 177-184. （in Chinese） [10] TANG F， LEI M， TANG Z， et al. Cadmium accumulation and its dynamic distribution in different rice varieties[J]. Journal of AgroEnvironment Science， 2013， 32（6）：1092-1098. （in Chinese）
[11] YU H， WANG JL， FANG W， et al. Cadmium accumulation in different rice cultivars and screening for pollutionsafe cultivars of rice[J]. Science of the Total Environment， 2006， 370： 302-309.
[12] LIU JG， QIAN M， CAI GL， et al. Uptake and translocation of Cd in different rice cultivars and the relation with Cd accumulation in rice grain[J]. Journal of Hazardous Materials， 2007， 143： 443-447.
[13] ZHENG T， LI TX， ZHANG XZ， et al. Enrichment characteristics of Cd in rice cadmium accumulation[J]. Scientia Agricultura Sinica， 2013， 46（7）： 1492-1500. （in Chinese）
[14] HUANG ZB， ZHANG BL， TIAN YY， et al. Study and application of humic acid in soil improvement[J]. Humic Acid， 2017（5）：1-4， 25. （in Chinese）
[15] PAI HC. Soil washing of cadmium contaminated soil by lowmolecular weight organic acids and humic acid[D]. Chengdu： Sichuan Agricultural University， 2015. （in Chinese）
Editor： Yingzhi GUANG Proofreader： Xinxiu ZHU
[Methods] Under the treatment of cadmium contaminated soil with a concentration of 0.58 mg/kg， the effects of "Glimmer" treatment on dry matter accumulation， yield and cadmium content of different rice varieties were studied by pot experiment.
[Results] Spraying "Glimmer" can increase the biological yield of rice， and the different types of rice showed the order of conventional rice>twoline hybrid rice>threeline hybrid rice. Among the conventional rice， most significant increase was observed in Huanghuazhan， and in twoline hybrid rice， C Liangyou 651 increased the most. The "Glimmer" treatment had an obvious yield increasing effect on conventional rice， among which such two varieties as Xiangwanxian 13 and Huanghuazhan had the largest increases， followed by the twoline hybrid rice， and a little effect was observed on the threeline hybrid rice. The "Glimmer" treatment resulted in a significant reduction in cadmium content in different types of rice， which decreased by 13.33%-26.09%， and seven varieties showed a reduction over 21.74%.
[Conclusions] The "Glimmer" treatment can significantly reduce the cadmium content in rice， and generally promote the dry matter accumulation and yield increase of rice， of which conventional rice performed better.
Key words Glimmer; Rice; Cadmium absorption; Yield
Rice is the second largest food crop in China. Nearly twothirds of the countrys population live on rice. Therefore， rice quality and safety are directly related to national health and social stability. Heavy metal cadmium is a nonessential growth element of crops， which is easily absorbed and enriched by crops in the soil and eventually endangers human health through the food chain. A large number of scholars have carried out more exploration and practice on the control of cadmium pollution， mainly aboutthe biochar remediation method， the application of soil acidification conditioner to improve the soil pH value， the method of replacing topsoil with guest soil， phytoremediation and other methods[1-3]. Phytoremediation technology is considered to be the main means of soil remediation at this stage[4]. Some studies have found that there are big differences in cadmium enrichment ability between rice varieties[5-10]， and the accumulation of cadmium in the grains of the same variety is greatly affected by soil cadmium changes[11-13]. "Glimmer" is a natural organic polymer compound， the main component of which is humic acid. Studies have shown that the use of humic acid to improve heavy metal contaminated soil can achieve a better remediation effect[14-15]. At present， there are few reports on the application of "Glimmer" foliar application to regulate the accumulation of cadmium in rice grains. In view of this， in this study， "Glimmer" was sprayed on the leaves and panicles of 12 different genotypes of rice during grain formation， and the effects of "Glimmer" treatment on dry matter accumulation， yield and cadmium accumulation in different types of rice varieties were analyzed， aiming at providing a theoretical basis for the regulation of low cadmium accumulation in rice grains. Materials and Methods
Experimental materials
Twelve rice varieties cultivated in large area and being popularized were selected， including four conventional rice varieties， namely Huanghuazhan， Xiangwanxian 13， Xiangwanxian 16 and Nongxiang 18， four twoline hybrid rice varieties， namely C Liangyou 651， Y Liangyou 3218， Fengliangyou 4 and Zhunliangyou 527， and four threeline hybrid rice varieties， namely， Shenyou 9588， Tianyou 998， Chuanxiang 8 and Nei 5 You 263.
Experimental methods
The 12 varieties were sprayed with "Glimmer" to serves as the "Glimmer" treatments， with spraying clear water as control. "Glimmer"humic acid was applied at 200 ml/667 m2， once at rupturing stage and once at heading stage. The rice was planted in plastic pots， which had a surface area of about 0.16 m2 （diameter： 45 cm）. Each pot contained 15 kg of cadmium contaminated soil （taken from the polluted farmland soil in the tin mine area of Lengshuijiang City）. The soil was airdried， finely sieved and repeatedly stirred， until the soil cadmium content was uniform. Rice was planted according to 3 holes per pot， 2 plants per hole. The splitplot experiment design was adopted with three replicates （four pots per variety）. After pregermination of rice varieties， the rice seedlings were first raised in Cdfree rice field. After 30 d， the seedlings were transplanted into the pots. After transplanting， a 2-3 cm water layer was maintained on the soil surface during the whole growth period.
Cultivation management： The pure water produced by the pure water equipment was used for irrigation， and the soil was flooded by 1-4 cm water during the whole growth period （that is， 4 cm water was introduced after transplanting， and when the water level naturally decreased to 1 cm， water was supplemented to 4 cm then）. The fertilizing amount was calculated according to the soil area. Specifically， 180 kg of pure nitrogen was applied per hectare under N∶P∶K=1∶0.5∶0.8. In the base fertilizer， N， P and K accounted for 50%， 100% and 40% of the total， respectively， and 50%， 0% and 60% of the total amounts were applied as the tillering fertilizer. The fertilizers were fully dissolved， and the nutrient solution was quantitatively applied into the pots to ensure that the amount of fertilizer applied to every pot was the same.
Analysis of dry weight and yield： Representative plants were divided into roots， stems， leaves and panicles （seeds）. After drying at 105 ℃， the different parts were dried at 80 ℃ to constant weight. The yield was determined after airdrying the seeds at maturation stage. Determination of heavy metal cadmium： Soil and rice samples were digested by MARS microwave digestion system （manufactured by CEM， USA）， and cadmium content was determined by inductively coupled plasma atomic emission spectroscopy （ICPAES）.
Data processing
The data were processed and analyzed using DPS and Excel software.
Results and Analysis
Effects of "Glimmer" on dry matter accumulation in different rice varieties
From the perspective of rice type， spraying "Glimmer" can slightly increase the biological yield of rice compared with spraying water （control）， and the increase order was conventional rice>twoline hybrid rice>threeline hybrid rice. Among the conventional rice， most significant increase was observed in Huanghuazhan， of which the total dry matter quantity was 43.90 and 55.35 g/plant at heading and maturation stages， respectively， which increased by 11.56% and 32.04% compared with the control， respectively. As to the twoline hybrid rice， C Liangyou 651 increased the most， and its total dry matter quantity was 41.52 and 51.46 g/plant at heading and maturation stages， respectively， which increased by 4.19% and 9.10% compared with the control， respectively. Analyzing from different parts of rice plants， spraying "Glimmer" can increase the dry weight of roots at heading stage and the dry matter quantities of roots， leaves and grains at maturation stages， but had no significant effect on the dry matter quantity of stems （Table 1）. It indicated that the application of "Glimmer" can increase the dry matter quantity of conventional rice Huanghuazhan， mainly the dry matter quantity of the roots and the weight of leaves at maturation stage， thereby increasing root absorption and leaf photosynthesis， and finally， its dry matter increased significantly at maturation stage.
Effects of "Glimmer" on yield and yield structure of different rice varieties
Table 2 shows the effects of "Glimmer" on the yield and yield structure of different genotypes of rice. As can be seen from Table 2， the rice varieties treated with "Glimmer" increased yield by 28%-36%， of which the yield of threeline hybrid rice was increased by 36%， and that of conventional rice was increased by 28%. The plant height， panicle length， number of grains per panicle， number of panicles， seed setting rate and 1 000grain weight were increased to certain extents after treatment. Meanwhile， it can be seen that there were certain differences between different rice varieties. The 1 000grain weight varied from 16.8 to 25.7 g. Among the difference varieties， such four varieties as Chuanxiang 8， Zhunliangyou 527， Nongxiang 18 and Nei 5 You 263 all had a 1 000grainweight over 25 g， while the two varieties， Huanghuazhan and Xiangwanxian 16， both exhibited a yield below 20 g. By comparing and analyzing these traits， it was found that the number of grains per panicle of C Liangyou 651 was 270 grains/panicle， Shenyou 9588 had the most effective panicles （12.43 panicles/plant）， and Nongxiang 18 exhibited the largest 1 000grain weight （26.8 g）. "Glimmer" has a higher yielding potential for conventional rice varieties such as Xiangwanxian 13 and Huanghuazhan. Jing ZHOU et al. Study on the Effect of "Glimmer" on Cadmium Absorption and Yield of Rice
Effects of "Glimmer" on cadmium content in different rice varieties
It can be seen from Table 3 that the accumulation of cadmium in different genotypes of rice after spraying "Glimmer" at heading stage was reduced to a certain extent， and the reductions were in the range of 13.33%-26.09%. Among the different types of rice， the conventional rice， twoline hybrid rice and threeline hybrid rice showed an average reduction of 20.03%， 22.11% and 19.80%， respectively. There were seven rice varieties of different genotypes exhibited a reduction over 21.74% after sprayed with "Glimmer"， namely， Nongxiang 18， Fengliangyou 4， C Liangyou 651， Nei 5 You 263， Zhunliangyou 527， Xiangwanxian 13 and Tianyou 998， and only 2 varieties showed a reduction less than 15.00%（Xiangwanxian 16 and Y Liangyou 3218）. This indicated that "Glimmer" had a little effect on the cadmium contents in different types of rice， but a greater impact on different genotypes of rice.
Conclusions and Discussion
The results of this study showed that the dry matter quantities in different types of rice increased after spraying "Glimmer"， and the increasing rule was that the increases of roots， panicles and total amount were significantly larger than those of stems， leaves and grains， i.e.， root>panicle>stem>leaf>grains. Different genotypes of rice increased in different degrees， which were expressed as conventional rice>twoline hybrid rice>threeline hybrid rice variety， and maturation stage>heading stage. It was also found that the conventional rice varieties and twoline hybrid rice varieties had higher yield increasing potential than threeline hybrid rice varieties. After the treatment with "Glimmer"， rice yield can be increased by 28%-36%， among which the yield increase of threeline hybrid rice yield was 36%， and that of conventional rice was 28%. The plant height， panicle length， number of grains per panicle， number of panicles， seed setting rate and 1 000grain weight increased to different degrees after treatment. Meanwhile， the accumulation of cadmium in different types of rice was significantly reduced after spraying "Glimmer" at heading stage， with a reduction of 13.33%-26.09%. There were no significant differencesin cadmium content between different types of rice， but the application of "Glimmer" treatment had a great effect on different genotypes of rice. Specifically， such seven varieties as Nongxiang 18， Fengliangyou 4， C Liangyou 651， Nei 5 You 263， Zhunliangyou 527， Xiangwanxian 13 and Tianyou 998 decreased more significantly. The results of this study were obtained by analyzing the effects of "Glimmer" on cadmium content， yield and dry matter accumulation in different types of rice cultivars under the conditions of planting rice cultivars in the potted soil contaminated with cadmiumat a low concentration of 0.58 mg/kg. Because the pot experiment had a certain influence on the growth and development of rice， the experimental results have yet to be further verified under the conditions of field cultivation. In addition， pot experiments can be carried out under moderate cadmiumcontaminated （1.0 mg/kg）and high cadmiumcontaminated （2.0 mg/kg） soil to further explore the effects of spraying "Glimmer" on yield， cadmium content and their change laws in different types of rice varieties， in order to better understand the impact of "Glimmer" on different genotypes of rice and provide a reference for largearea applications in field.
References
[1] SUN XJ. Study on the characteristics and treatment of heavy metal pollution in soil[J]. China Resources Comprehensive Utilization， 2018， 36（4）： 144-145，151. （in Chinese）
[2] LI XT， GU ST， ZHENG WJ， et al. Research progress on remediation technology of heavy metal contaminated soil[J]. Environmental Science & Technology， 2013， 36（S2）： 203-208. （in Chinese）
[3] GU JG， ZHOU QX. Cleaning up through phytoremediation： A review of Cd contaminated soils[J]. Ecological Science， 2002， 21（4）： 352-356. （in Chinese）
[4] MCGRATH SP， ZHAO J， LOMBI E. Phytoremediation of metals， metalloids， and radionuclides[J]. Advances in Agronomy， 2002， 75： 1-56. （in Chinese）
[5] ZHANG BJ， LUO GL， WEI YH， et al. Dynamic difference analysis of cadmium accumulation in different genotypes of rice[J]. Chinese Agricultural Science Bulletin， 2015， 31（9）： 25-30. （in Chinese）
[6] LI KQ， LIU JG， LU XL， et al. Uptake and distribution of cadmium in different rice cultivars[J]. Journal of AgroEnvironment Science， 2003， 22（5）： 529-532. （in Chinese）
[7] ZHANG XZ， ZHANG HJ， LI TX， et al. Differences in Cdtolerance of rice and screening for Cd lowaccumulation rice germplasm resources[J]. Chinese Journal of EcoAgriculture， 2013， 21（11）： 1434-1440. （in Chinese）
[8] CAI QL， LIN DS， WANG G， et al. Differences in cadmium accumulation and transfer capacity among different types of rice cultivars[J]. Journal of AgroEnvironment Science， 2016， 35（6）： 1028-1033. （in Chinese）
[9] LONG XL， XIANG XC， XU YF， et al. Absorption， transfer and distribution of Cd in indica and japonica rice under Cd Stress[J]. Chinese Journal of Rice Science， 2014， 28（2）： 177-184. （in Chinese） [10] TANG F， LEI M， TANG Z， et al. Cadmium accumulation and its dynamic distribution in different rice varieties[J]. Journal of AgroEnvironment Science， 2013， 32（6）：1092-1098. （in Chinese）
[11] YU H， WANG JL， FANG W， et al. Cadmium accumulation in different rice cultivars and screening for pollutionsafe cultivars of rice[J]. Science of the Total Environment， 2006， 370： 302-309.
[12] LIU JG， QIAN M， CAI GL， et al. Uptake and translocation of Cd in different rice cultivars and the relation with Cd accumulation in rice grain[J]. Journal of Hazardous Materials， 2007， 143： 443-447.
[13] ZHENG T， LI TX， ZHANG XZ， et al. Enrichment characteristics of Cd in rice cadmium accumulation[J]. Scientia Agricultura Sinica， 2013， 46（7）： 1492-1500. （in Chinese）
[14] HUANG ZB， ZHANG BL， TIAN YY， et al. Study and application of humic acid in soil improvement[J]. Humic Acid， 2017（5）：1-4， 25. （in Chinese）
[15] PAI HC. Soil washing of cadmium contaminated soil by lowmolecular weight organic acids and humic acid[D]. Chengdu： Sichuan Agricultural University， 2015. （in Chinese）
Editor： Yingzhi GUANG Proofreader： Xinxiu ZHU