Effect of Exogenous Methyl Jasmonate on Growth and Nitrogen Uptake of Tobacco Seedlings

Wu Qiangwen; Liu Keqiang; Han Shixin; He Yingyu; Tang Tingting; Li Shuaibing; Wang Yong; Zhao Min; Zeng Weiguo; Yan Huifeng

doi:10.14083/j.issn.1001-4942.2025.05.016

Abstract：The experiment was aimed to investigate the effects of exogenous methyl jasmonate(MeJA)on growth and development of flue-cured tobacco seedlings and nitrogen accumulation in different organs in or-der to provide theoretical supports for regulation of flue-cured tobacco growth and development and nitrogen ab-sorption by exogenous hormones.The flue-cured tobacco variety Zhongchuan 208 was used as test material,and three concentrations of 0.45,4.5 and 45 μmol·L-1 MeJA were sprayed on leaves with water spraying as control.The effects of different treatments on the growth and development of flue-cured tobacco seedlings,dry matter accumulation in each organ,root morphological characteristics and nitrogen content in each organ were studied by pot method.The results showed that spraying 0.45 μmol·L-1 MeJA and 4.5 μmol·L-1 MeJA had no significant effects on plant height,stem circumference and new leaf area of flue-cured tobacco seedlings.At 7 days after treatment,the dry matter accumulation of roots under 0.45 μmol·L-1 MeJA treatment and leaves un-der 4.5 μmol·L-1 MeJA treatment were significantly increased compared with the control.However,at 14 days after treatment,there was no significant difference in dry matter accumulation of each organ under 0.45 μmol·L-1 MeJA treatment compared with the control,the dry matter accumulation of roots and leaves when treated with 4.5 μmol·L-1 MeJA was increased compared with the control,and that of roots reached a signifi-cant level.At 7 days after treatment,45 μmol·L-1 MeJA treatment had no significant effect on plant height,stem circumference and new leaf area,and also dry matter accumulation of various organs.When treated for 14 days,the new leaf area of seedlings significantly reduced,and the dry matter accumulation of stems and leaves also decreased compared with the control.The three concentrations of MeJA treatments had no significant effect on leaf thickness,but increased the specific leaf weight and leaf density,total root length,total surface area and total volume,and most increased the leaf nitrogen content and the proportion of leaf nitrogen content in plants.In conclusion,foliar spraying with 0.45 and 4.5 μmol·L-1 MeJA was beneficial to dry matter accumula-tion of flue-cured tobacco seedlings,while 45 μmol·L-1 MeJA had little effect on dry matter accumulation.The application of MeJA with different concentrations promoted the development of leaves and roots,promoted the transfer of nitrogen to leaves,and increased the nitrogen content in leaves.