Scientia Agricultura Sinica ›› 2022, Vol. 55 ›› Issue (3): 467-478.doi: 10.3864/j.issn.0578-1752.2022.03.004

• TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION • Previous Articles     Next Articles

The Photosynthesis Characteristics of Colored Rice Leaves and Its Relation with Antioxidant Capacity and Anthocyanin Content

CHEN TingTing(),FU WeiMeng(),YU Jing,FENG BaoHua,LI GuangYan,FU GuanFu,TAO LongXing   

  1. State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006
  • Received:2021-04-06 Accepted:2021-06-21 Online:2022-02-01 Published:2022-02-11
  • Contact: GuanFu FU,LongXing TAO E-mail:chentingting@caas.cn;fuwmeng@163.com

Abstract:

【Objective】 In recent years, due to colored rice unique appearance and special nutritional value, it has been developed rapidly in the sightseeing agriculture, selection and production of special nutritional rice. The objective of this study was to elucidate the mechanism underlying the photosynthetic response of leaves in colored rice to light.【Method】 In this experiment, four rice varieties with different chlorophyll content in leaves were selected, including deep purple (DP), pale green (PG), dark green (DG) and pale purple (PP). The change characteristics of leaf photosynthesis were studied and the response mechanisms were revealed.【Result】 The results indicated that the highest chlorophyll content was showed in DP, followed by the DG and PP, while the lowest value was found in PG. Under this case, the PG variety attained the highest value of actual fluorescence quantum efficiency of PSII, photosynthetic rate, ribulose-1,5-bisphosphate carboxylase (Rubisco) activity and total dry matter weight, which were significantly higher than those in the other varieties. The content of hydrogen peroxide and malondialdehyde in PG leaves were significantly lower than those in other rice varieties. Besides, there was no significant difference in leaf chlorophyll content and carotenoid content between DP and DG, while the actual fluorescence quantum efficiency of PSII, net photosynthetic rate, Rubisco activity in leaves of DP were significantly higher than those of DG. Correspondingly, the activities of antioxidant enzymes in leaves of DP were significantly higher than those of DG, while the content of hydrogen peroxide and malondialdehyde in leaves of DP were significantly lower than those of DG. This might be related to the anthocyanin content in the leaves, because the anthocyanin content in the leaves of DP was significantly higher than that of DG. The leaf photosynthetic rate was significantly increased and hydrogen peroxide content was significantly decreased after foliar application of anthocyanin. 【Conclusion】 It was inferred that anthocyanin might exert important role in alleviating the inhibition effect caused by excess optical quantum on the photosynthesis of leaves under natural conditions. The results could provide a theoretical basis for rice high light efficiency breeding, and cultivation technology exploitation for collaborative development in grain yield and quality of colored rice.

Key words: colored rice, chlorophyll, photosynthesis, antioxidant capacity, anthocyanin

Table 1

The growth period of the rice varieties in this experiment"

供试品种
Variety
平均生育期
Average whole growing period (d)
播种日期
Sowing date (M-D)
抽穗日期
Heading date (M-D)
收获日期
Harvest date (M-D)
2018 2019 2018 2019 2018 2019
深紫叶DP14005-1005-2008-0808-2009-2410-08
淡绿叶PG13405-1005-2008-0108-1209-1910-02
深绿叶/常规叶色DG13405-1005-2008-0208-1209-1910-02
淡紫叶PP13705-1005-2008-0408-1609-2210-05

Table 2

The grain yield and its components of rice with different leaf colors"

供试品种
Variety
穗数
Panicle numbers per pot
每穗粒数
Spikelets numbers per panicle
结实率
Seed-setting rate (%)
粒重
Grain weight (mg)
产量
Yield (g/pot)
深紫叶DP18.2a95.8b77.7a21.4a29.0b
淡绿叶PG17.9a108.7a79.1a21.6a33.3a
深绿叶/常规叶色DG18.5a91.8b74.8ab20.5b26.1c
淡紫叶PP17.8a103.1a79.4a21.9a31.9ab

Fig. 1

Plant height and panicle length of rice varieties with different leaf colors at maturity(a) Plant morphology at maturity; (b) Panicle phenotype; (c) Plant height; (d) Panicle length. DP, deep purple; PG, pale green; DG, dark green; PP, pale purple. Different letters above column indicate significant difference among the rice varieties with different leaf color (P<0.05). The same as below"

Fig. 2

Contents of chlorophyll and carotenoids in leaves of rice with different leaf colors(a) Growth phenotype at tillering stage; (b) Leaf phenotype; (c) Chloropyll content; (d ) Carotenoid content. Chl: Chlorophyll(a) Growth phenotype at tillering stage; (b) Leaf phenotype; (c) Chloropyll content; (d ) Carotenoid content. Chl: Chlorophyll"

Fig. 3

Chlorophyll fluorescence parameters of rice leaves with different leaf colors"

Fig. 4

Dry matter accumulation and leaf photosynthesis of rice with different leaf colors"

Fig. 5

Antioxidant enzyme activities of rice leaves with different leaf colors"

Fig. 6

The content of H2O2 and MDA in rice leaves with different leaf colors"

Table 3

Correlations of the anthocyanin content in rice leaves with the photosynthesis and chlorophyll fluorescence parameters, antioxidant enzyme activity, peroxides content, dry matter weight and grain yield"

与相关
Correlated with
花青素含量
Anthocyanin content
叶绿素含量
Chlorophyll content
类胡萝卜素含量
Carotenoids content
光合荧光参数 Photosynthesis and chlorophyll fluorescence parameters
净光合速率Net photosynthetic rate0.877*0.6130.016
核酮糖-1,5-二磷酸羧化酶活 Rubisco activity0.995**0.4270.250
最大荧光量子效率 Maximum fluorescence quantum efficiency0.0190.2610.179
PSI实际光量子效率 Actual fluorescence quantum efficiency of PSI0.956**0.6050.018
PSII实际光量子效率 Actual fluorescence quantum efficiency of PSII0.983**0.3860.136
抗氧化酶类Antioxidant enzyme
过氧化物酶POD activity0.946**0.4820.108
超氧化物歧化酶活性SOD activity0.996**0.3600.223
过氧化氢酶CAT activity0.965**0.2930.112
过氧化物含量Peroxides content
过氧化氢含量H2O2 content-0.998**-0.400-0.235
丙二醛含量MDA content-0.991**-0.438-0.320
其他Others
干物质重 Dry matter weight0.974**0.5430.277
产量Yield0.841*0.4530.218

Fig. 7

Anthocyanin content of rice leaves with different leaf colors"

Fig. 8

Effects of foliar application of anthocyanin on photosynthetic rate and hydrogen peroxide contentH2O: Foliar application of water; Atc: Foliar application of anthocyanin"

Fig. 9

Analysis of the pathways of anthocyanins acting on leaf photosynthesis under natural conditions Red → indicates the effect of promotion, and green ┤indicates inhibition in the figure"

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