The effect of auxins （IAA or IBA at 100, 200, 500 mg.L J） on rooting and sprouting parameters differed significantly （p 〈 0.05）. Rooting and sprouting percentages were higher in some treatments while other parame...The effect of auxins （IAA or IBA at 100, 200, 500 mg.L J） on rooting and sprouting parameters differed significantly （p 〈 0.05）. Rooting and sprouting percentages were higher in some treatments while other parameters were significantly higher in other treatments. The results of the present study revealed that rooting was significantly （p 〈 0.05） affected by the length of cuttings, as well as the position of shoots and type of cuttings. On average, 86.0 per cent rooting was observed in the 30-cm long cuttings com- pared to the other two lengths of cuttings, i.e., 20 and 25 cm, irrespective of any auxin treatment. In a control set, without any auxin treatment, a maximum of 60.0% rooting was recorded in the 30-cm long cuttings and a minimum of 40.0% of the cuttings rooted in the 20-cm long cuttings. Similarly, cuttings collected from the lower and upper portions of shoots resulted in 72.5 and 52.5 per cent rooting respectively, irrespective of auxin treatments. Maximum rooting was observed in the lower portion （40.0%） of cutting com- pared to the upper portion （30.0%） in the control set without auxin treatment. Leafless branches produced maximum （72.0%） rooting compared to the leafy cuttings （35.0%）, irrespective of the auxin treatment. The leafy cuttings produces a minimum of 15.0% sprout- ing and rooting in the control set.展开更多
Poor seedling emergence is a challenge for direct seeding of rice under deep-sowing field conditions.Here we reveal that UDP-glucosyltransferase OsUGT75A promotes rice seedling emergence under deepsowing conditions by...Poor seedling emergence is a challenge for direct seeding of rice under deep-sowing field conditions.Here we reveal that UDP-glucosyltransferase OsUGT75A promotes rice seedling emergence under deepsowing conditions by increasing shoot length.Expression of OsUGT75A was higher in the middle regions of the shoot and in shoots under deep-sowing conditions.Levels of free abscisic acid(ABA)and jasmonates(JA)were higher in shoots of OsUGT75A mutants than in those of wild-type plants,and OsUGT75A mutants were more sensitive to ABA and JA treatments.Reduced shoot length was attributed to higher ABA INSENSITIVE 3(OsABI3)expression and lower JASMONATE-ZIM domain protein(OsJAZ)expression in shoots.Shoot extension by OsUGT75A is achieved mainly by promotion of cell elongation.An elite haplotype of OsUGT75A associated with increased shoot length was identified among indica rice accessions.OsUGT75A acts to increase seedling emergence under deep-sowing conditions.展开更多
[Objective] This study was to investigate the allelopathic effects of J.curcas leaf leachates on seedling growth and antioxidative enzymes,and thus to reveal physiologically allelopathic effects of J.curcas trees on u...[Objective] This study was to investigate the allelopathic effects of J.curcas leaf leachates on seedling growth and antioxidative enzymes,and thus to reveal physiologically allelopathic effects of J.curcas trees on undergrowth plants.[Method] The allelopathic effects of leaf leachates of Jatropha curcas amended into soil were determined on the growth,proline and malondialdehyde（MDA） contentas well as superoxide dismutase（SOD）,catalase（CAT）,ascorbate peroxidase（APX）,guaiacol peroxidase（POD） in roots of marigold（Tagetes erecta） seedlings.[Results] The application of leaf leachates of J.curcas in the soil significantly inhibited the shoot and root length of marigold compared to un-amended soils.The leaf leachates increased the O-2,H2O2,MDA and proline content in the roots of marigold seedlings.The effects increased with the ascending of leaf leachates concentration.In addition,superoxide dismutase（SOD） and guaiacol peroxidase（POD） were not remarkably affected by the leachates at lower concentrations,but at higher concentration,SOD activity was ascended.Similarly,the activities of CAT and APX were also significantly increased with the increase of leachates concentrations.[Conclusion] These results show that J.curcas can release the phytotoxic compound（s） into soil,which are inhibitory to certain test species by interfering with physiological process.展开更多
文摘The effect of auxins （IAA or IBA at 100, 200, 500 mg.L J） on rooting and sprouting parameters differed significantly （p 〈 0.05）. Rooting and sprouting percentages were higher in some treatments while other parameters were significantly higher in other treatments. The results of the present study revealed that rooting was significantly （p 〈 0.05） affected by the length of cuttings, as well as the position of shoots and type of cuttings. On average, 86.0 per cent rooting was observed in the 30-cm long cuttings com- pared to the other two lengths of cuttings, i.e., 20 and 25 cm, irrespective of any auxin treatment. In a control set, without any auxin treatment, a maximum of 60.0% rooting was recorded in the 30-cm long cuttings and a minimum of 40.0% of the cuttings rooted in the 20-cm long cuttings. Similarly, cuttings collected from the lower and upper portions of shoots resulted in 72.5 and 52.5 per cent rooting respectively, irrespective of auxin treatments. Maximum rooting was observed in the lower portion （40.0%） of cutting com- pared to the upper portion （30.0%） in the control set without auxin treatment. Leafless branches produced maximum （72.0%） rooting compared to the leafy cuttings （35.0%）, irrespective of the auxin treatment. The leafy cuttings produces a minimum of 15.0% sprout- ing and rooting in the control set.
基金supported by the Key-Area Research and Development Program of Guangdong Province(2022B0202060006)the Natural Science Foundation of Guangdong Province(2023A1515012052,2023A1515012092)+2 种基金the Science and Technology Project of Guangzhou(2023A04J0749,2023A04J1452)the Special Fund for Student Cultivation of Scientific and Technological Innovation of Guangdong Province(pdjh2021b0084)the Double First-Class Discipline Promotion Project of South China Agricultural University(2021B10564001).
文摘Poor seedling emergence is a challenge for direct seeding of rice under deep-sowing field conditions.Here we reveal that UDP-glucosyltransferase OsUGT75A promotes rice seedling emergence under deepsowing conditions by increasing shoot length.Expression of OsUGT75A was higher in the middle regions of the shoot and in shoots under deep-sowing conditions.Levels of free abscisic acid(ABA)and jasmonates(JA)were higher in shoots of OsUGT75A mutants than in those of wild-type plants,and OsUGT75A mutants were more sensitive to ABA and JA treatments.Reduced shoot length was attributed to higher ABA INSENSITIVE 3(OsABI3)expression and lower JASMONATE-ZIM domain protein(OsJAZ)expression in shoots.Shoot extension by OsUGT75A is achieved mainly by promotion of cell elongation.An elite haplotype of OsUGT75A associated with increased shoot length was identified among indica rice accessions.OsUGT75A acts to increase seedling emergence under deep-sowing conditions.
基金Supported by National Key Technologies R&D Program of China(2008BAK51B01-7-3)~~
文摘[Objective] This study was to investigate the allelopathic effects of J.curcas leaf leachates on seedling growth and antioxidative enzymes,and thus to reveal physiologically allelopathic effects of J.curcas trees on undergrowth plants.[Method] The allelopathic effects of leaf leachates of Jatropha curcas amended into soil were determined on the growth,proline and malondialdehyde（MDA） contentas well as superoxide dismutase（SOD）,catalase（CAT）,ascorbate peroxidase（APX）,guaiacol peroxidase（POD） in roots of marigold（Tagetes erecta） seedlings.[Results] The application of leaf leachates of J.curcas in the soil significantly inhibited the shoot and root length of marigold compared to un-amended soils.The leaf leachates increased the O-2,H2O2,MDA and proline content in the roots of marigold seedlings.The effects increased with the ascending of leaf leachates concentration.In addition,superoxide dismutase（SOD） and guaiacol peroxidase（POD） were not remarkably affected by the leachates at lower concentrations,but at higher concentration,SOD activity was ascended.Similarly,the activities of CAT and APX were also significantly increased with the increase of leachates concentrations.[Conclusion] These results show that J.curcas can release the phytotoxic compound（s） into soil,which are inhibitory to certain test species by interfering with physiological process.
