[Effect of exogenous carbon monoxide donor hematin on seed germination and physiological characteristics of Cassia obtusifolia seedlings under NaCl stress].

OBJECTIVE: In order to get the method to improve the salt resistance of seeds and seedlings for Cassia obtusbifolia under NaCl stress, seed germination and physiological characteristics of C. obtusifolia seedlings were studied. METHOD: Several physiological indexes of C. obtusifolia seeds treated with exogenous carbon monoxide donor hematin under NaCl stress like the germination vigor, germination rate, germination index and vigor index were measured. And other indexes like the relative water content, the contents of photosynthetic pigment, chlorophyll fluorescence parameters, the contents of soluble sugar, protein and proline, malondialdehyde (MDA), the activities of superoxide (SOD), peroxidase (POD) and catalase (CAT) were also measured. RESULT: The germination indexes of C. obtusifolia seeds under NaCl stress had been inhibited obviously. But after the treatment of hematin, every germination indexes were all increased. The result showed that the treatment of exogenous CO donor hematin obviously improved the germination vigor, germination rate, germination index and vigor index, increased the content of chlorophyll a, chlorophyll b, total chlorophyll, improved the photochemical efficiency of photosystem II (Fv/Fm), photochemical efficiency (Fv'/Fm'), PS II actual photochemical efficiency (phiPS II), photochemical quench coefficient (qP), decreased non-photochemical quenching coefficient (NPQ) and the content of malondialdehyde (MDA) , increased the relative water content of leaves and the content of soluble surge, protein and proline. Meanwhile, the results also indicated that CO improved the activities of superoxide (SOD), peroxidase (POD) and catalase (CAT). The effects of CO could be reversed when CO scavenger Hb is added. CONCLUSION: Exogenous CO donor hematin with appropriate concentration could significantly alleviate the damages to the seeds and seedlings of C. obtusifolia under NaCl stress and promote the salt resistance of the seeds and seedlings through improving the germination indexes, the photochemical efficiency and the antioxidase activities of the seedlings.

[Effect of exogenous nitric oxide donor SNP on seed germination and antioxidase activities of Perilla frutescens seedlings under NaCl stress].

OBJECTIVE: To explore the method of improving the salt resistance ability of seeds and seedlings of Perilla frutescens under NaCl stress. METHODS: Physiological indexes of Perilla frutescens seeds treated by sodium nitroprusside (SNP) under NaCl stress like the germination vigor, germination rate, germination index and vigor index were measured. And other indexes like the activities of nitrate reductase (NR), malondialdehyde (MDA), superoxide (SOD), peroxidase (POD) and catalase (CAT) were also measured. RESULTS: The germination indexes of Perilla frutescens seeds under NaCl stress had obvious inhibition. But after the treatment with different concentrations of SNP, every germination indexes were all increased. And the seeds that treated with SNP with the concentration of 0.1 mmol/L has the most significantly increase in every index. The germination vigor was 60.4%, the germination rate was 78.3%, the germination index and vigor index were 13.7 and 0.1093 respectively. The content of MDA was decreased after the treatment of SNP. The activities of four enzymes included NR, SOD, POD and CAT were increased with the treatment of SNP, and get the maximin (1.52 microg/g x h, 0.32 U/mg, 5.9 U/mg and 4.8 U/mg respectively) with the concentration of 0.1 mmol/L SNP. CONCLUSION: SNP with concentration of 0.1 mmol/L could significantly alleviate the damages to the seeds and seedlings of Perilla frutescens under NaCl stress, and promote the salt resistance of the seeds and seedlings.

[Effect of exogenous Ca2+ and NO donor SNP on seed germination and antioxidase activities of Perilla frutescens seedlings under NaCl stress].

OBJECTIVE: In order to find a method for improving the salt resistance of seeds and seedlings for Perilla frutescens under NaCl stress, seed germination and physiological characteristics of P. frutescens seedlings were studied. METHOD: Several physiological indexes of P. frutescens seeds treated by Ca2+ and sodium nitroprusside (SNP) under NaCl stress like the germination vigor, germination rate, germination index and vigor index were measured. And other indexes like the biomass of the seedlings, the content of malondialdehyde (MDA) in leaves, the activities of superoxide (SOD), peroxidase (POD) and catalase (CAT) were also measured. RESULT: The germination of P. frutescens seeds under NaCl stress was inhibited obviously. But after the treatment with Ca2+ and SNP, all of the germination indexes increased. And the seeds that treated with SNP + Ca2+ had the most significantly increase in all indexes. The germination vigor was 65.1%, the germination rate was 89.3%, the germination index and vigor index were 13.9 and 0.1109, respectively. The content of MDA decreased after the treatment. The activities of three enzymes include SOD, POD and CAT were increased by the treatment and get the maximin 0.84, 5.71 and 4.92 U x mg(-1) respectively. And the EGTA showed an obvious inhibition to the effect of SNP on P. frutescens. CONCLUSION: SNP (0.1 mmol x L(-1)) and Ca2+ (10 mmol x L(-1)) could significantly alleviate the damages to the seeds and seedlings of P. frutescens under NaCl stress, and promote the salt resistance of the seeds and seedlings. These results might suggest that exogenous NO might enhance P. frutescens salt resistance and alleviate salt injury possible by enhancing Ca2+ influx by activating Ca2+ channels and improving concentration of Ca2+ of P. frutescens seedlings.

[Effect of exogenous Ca2+, ALA, SA and Spd on seed germination and physiological characteristics of Perilla frutescens seedlings under NaCl stress].

OBJECTIVE: To find a method for improving the salt resistance of seeds and seedlings for Perilla Frutescens under NaCl stress, seed germination and physiological characteristics of P. frutescens seedlings were studied. METHOD: Several physiological indexes of P. frutescens seeds treated with different concentrations of Ca2+, 5-aminolevulinic acid (ALA), salicylic acid (SA) and spermidine (Spd) under NaCl stress like the germination vigor, germination rate, germination index and vigor index were measured. And other indexes like the biomass of the seedlings, the content of malondialdehyde (MDA) in leaves, the activities of superoxide (SOD), peroxidase (POD) and catalase (CAT) were also measured. RESULT: The germination of P. frutescens seeds under NaCl stress (100 mmol x L(-1)) was inhibited obviously. But after the treatment with Ca2+, ALA , SA and Spd, all germination indexes were increased. Ca2+ (10 mmol x L(-1)), ALA (100 mg x L(-1)), SA (50 mg x L(-1)) and Spd (0.25 mmol x L(-1)) could obviously alleviate the damage of salt stress to the seeds of P. frutescens. ALA (100 mg x L(-1)) significantly increased all indexes. The germination vigor was 65.3%, the germination rate was 89.7%, the germination index and vigor index were 15.2 and 0.1238, respectively. All treatments decreased the content of MDA in leaves. The activities of three enzymes including SOD, POD and CAT were all increased. ALA (100 mg x L(-1)) had the enzymes activity reach the maximum with 0.72, 6, 82 and 5.64 U x mg(-1), respectively. CONCLUSION: Ca2+ ALA , SA and Spd with appropriate concentration could significantly alleviate the damages to the seeds and seedlings of P. frutescens under NaCl stress and promote the salt resistance of the seeds and seedlings.