Effects of substrates,type of auxin,treatment concentration and time on rooting ability of Acacia mangium were systematically studied,and the change trend of rooting ability over time were analyzed.The results obtaine...Effects of substrates,type of auxin,treatment concentration and time on rooting ability of Acacia mangium were systematically studied,and the change trend of rooting ability over time were analyzed.The results obtained from the experiment indicated that the substrate of yellow subsoil could improve the rooting rate of the cuttings significantly.IBA was superior to other auxins in increase the number of mean roots and the longest root length.And general rooting effect for different treatments was evaluated based on subordinate function values analysis.The optimized combinations were the cutting treated by IBA 400 mg·L-1 soaked for 2 hours.Callus were occurred in 5 d after cutting,and higher rooting period occurred in 10—15 d and 25—30 d after cutting.展开更多
Shoots of Citrus sp. Kuharske were used to develop protocols for rooting reportedly HLB resistance rootstocks under intermittent mist. Investigated were shoot maturity, nodes per cutting, leaves per cutting, effects o...Shoots of Citrus sp. Kuharske were used to develop protocols for rooting reportedly HLB resistance rootstocks under intermittent mist. Investigated were shoot maturity, nodes per cutting, leaves per cutting, effects of buds, auxin concentrations and auxin solvent. Shoot maturity was most influential for success, with cuttings taken below the first 30 cm of active terminal growth producing greater root generation. Use of a thickening agent (Natrosal) to dilute the commercial auxin was second most in importance for rooting success. Root mass increased with increasing number of leaves. Cutting stems between nodes or below the lowest bud were inconsequential. To produce maximum number of viable cuttings, single node-single leaf cuttings were preferred. Single bud cuttings produced one shoot after rooting. This was adventitious since multi-node cuttings usually sprouted new shoots that would need to be removed before budded. Evaluation of the best combination of auxin and cutting-related attributes were evaluated with four additional common rootstocks in June 2016. Rooting was 100% successful. A quick dip (0.5 s) in a 7500 ppm solution of Dip&Gro produced the most root generation in six weeks for all rootstocks. Root quantity varied by rootstock.展开更多
Auxin regulates cell division and elongation of the primordial cells through its concentration and then shaped the plant architecture. Cell division and elongation form the internode of soybean and result in different...Auxin regulates cell division and elongation of the primordial cells through its concentration and then shaped the plant architecture. Cell division and elongation form the internode of soybean and result in different plant heights and lodging resistance. Yet the mechanisms behind are unclear in soybean. To elucidate the mechanism of the concentration difference of auxin related to stem development in soybean, samples of apical shoot, elongation zone, and mature zone from the developing stems of soybean seedlings, Charleston, were harvested and measured for auxin concentration distributions and metabolites to identify the common underlying mechanisms responsible for concentration difference of auxin. Distribution of indole-3-acetic acid(IAA), indole-3-butyric acid(IBA), and methylindole-3-acetic acid(Me-IAA) were determined and auxin concentration distributions were found to have a complex regulation mechanism. The concentrations of IAA and Me-IAA in apical shoot were significantly different between elongation zone and mature zone resulting in an IAA gradient. Tryptophan dependent pathway from tryptamine directly to IAA or through indole-3-acetonitrile to IAA and from indole-3-propionic acid(IPA) to IAA were three primary IAA synthesis pathways. Moreover, some plant metabolites from flavonoid and phenylpropanoid synthesis pathways showed similar or reverse gradient and should involve in auxin homeostasis and concentration difference. All the data give the first insight in the concentration difference and homeostasis of auxin in soybean seedlings and facilitate a deeper understanding of the molecular mechanism of stem development and growth. The gathered information also helps to elucidate how plant height is formed in soybean and what strategy should be adopted to regulate the lodging resistance in soybean.展开更多
文摘Effects of substrates,type of auxin,treatment concentration and time on rooting ability of Acacia mangium were systematically studied,and the change trend of rooting ability over time were analyzed.The results obtained from the experiment indicated that the substrate of yellow subsoil could improve the rooting rate of the cuttings significantly.IBA was superior to other auxins in increase the number of mean roots and the longest root length.And general rooting effect for different treatments was evaluated based on subordinate function values analysis.The optimized combinations were the cutting treated by IBA 400 mg·L-1 soaked for 2 hours.Callus were occurred in 5 d after cutting,and higher rooting period occurred in 10—15 d and 25—30 d after cutting.
文摘Shoots of Citrus sp. Kuharske were used to develop protocols for rooting reportedly HLB resistance rootstocks under intermittent mist. Investigated were shoot maturity, nodes per cutting, leaves per cutting, effects of buds, auxin concentrations and auxin solvent. Shoot maturity was most influential for success, with cuttings taken below the first 30 cm of active terminal growth producing greater root generation. Use of a thickening agent (Natrosal) to dilute the commercial auxin was second most in importance for rooting success. Root mass increased with increasing number of leaves. Cutting stems between nodes or below the lowest bud were inconsequential. To produce maximum number of viable cuttings, single node-single leaf cuttings were preferred. Single bud cuttings produced one shoot after rooting. This was adventitious since multi-node cuttings usually sprouted new shoots that would need to be removed before budded. Evaluation of the best combination of auxin and cutting-related attributes were evaluated with four additional common rootstocks in June 2016. Rooting was 100% successful. A quick dip (0.5 s) in a 7500 ppm solution of Dip&Gro produced the most root generation in six weeks for all rootstocks. Root quantity varied by rootstock.
基金financially supported by the National Natural Science Foundation of China(31571693)the earmarked fund for China Agriculture Research System(CARS-04-04B)。
文摘Auxin regulates cell division and elongation of the primordial cells through its concentration and then shaped the plant architecture. Cell division and elongation form the internode of soybean and result in different plant heights and lodging resistance. Yet the mechanisms behind are unclear in soybean. To elucidate the mechanism of the concentration difference of auxin related to stem development in soybean, samples of apical shoot, elongation zone, and mature zone from the developing stems of soybean seedlings, Charleston, were harvested and measured for auxin concentration distributions and metabolites to identify the common underlying mechanisms responsible for concentration difference of auxin. Distribution of indole-3-acetic acid(IAA), indole-3-butyric acid(IBA), and methylindole-3-acetic acid(Me-IAA) were determined and auxin concentration distributions were found to have a complex regulation mechanism. The concentrations of IAA and Me-IAA in apical shoot were significantly different between elongation zone and mature zone resulting in an IAA gradient. Tryptophan dependent pathway from tryptamine directly to IAA or through indole-3-acetonitrile to IAA and from indole-3-propionic acid(IPA) to IAA were three primary IAA synthesis pathways. Moreover, some plant metabolites from flavonoid and phenylpropanoid synthesis pathways showed similar or reverse gradient and should involve in auxin homeostasis and concentration difference. All the data give the first insight in the concentration difference and homeostasis of auxin in soybean seedlings and facilitate a deeper understanding of the molecular mechanism of stem development and growth. The gathered information also helps to elucidate how plant height is formed in soybean and what strategy should be adopted to regulate the lodging resistance in soybean.
