Microarray analysis of humic acid effects on Brassica napus growth: Involvement of N, C and S metabolisms
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Background & aims
Winter rapeseed (Brassica napus) is characterized by a low N recovery in seeds and requires high rates of fertilization to maintain yield. Its nutrient use efficiency could be improved by addition of a biostimulant such as humic acids whose physiological effects have been described previously in some plant species. However, to our knowledge, no study has focused on transcriptomic analyses to determine metabolic targets of this extract.
A preliminary screening of ten humic acids revealed a significant effect of one of them (HA7) on rapeseed root growth. Microarray analysis was then used on HA7-treated or non-treated plants to characterize changes in gene expression that were further supported by physiological evidence.
Stimulation of nitrogen uptake (+15% in shoots and +108% in roots) and assimilation was found to be increased in a similar manner to growth while sulfate content (+76% in shoots and +137% in roots) was more strongly stimulated leading to higher sulfate accumulation. In parallel, microscopic analysis showed an enhancement of chloroplast number per cell.
It is therefore suggested that HA7, which promotes plant growth and nutrient uptake, could be used as a supplementary tool to improve rapeseed nitrogen use efficiency.
KeywordsBrassica napus Humic acid Microarray Growth promotion Nutrient uptake Chloroplast
This study was a part of AZOSTIMER project selected and supported by the Pôle de compétitivité Mer-Bretagne and funded by the French FUI (Fond Unique Interministériel), Brittany Region and Saint-Malo Agglomeration. We thank Marie-Paule Bataillé and Raphaël Ségura for IRMS analyses. We acknowledge Patrick Beauclair for LICOR measurements, Julie Levallois for technical assistance in RNA extractions and q-PCR analyses, Xavier Sarda and Anne-Françoise Ameline for helping with plant culture and harvest and finally Nicolas Elie from GRECAN (Groupe Régional d’Etude sur le CANcer, Histo-imagerie quantitative, Caen, France) for microscopic analysis. We thank Laurence Cantrill for improving the English of the manuscript.
- Aguirre E, Leménager D, Bacaicoa E, Fuentes M, Baigorri R, Zamarreño AM, García-Mina JM (2009) The root application of a purified leonardite humic acid modifies the transcriptional regulation of the main physiological root responses to Fe deficiency in Fe-sufficient cucumber plants. Plant Physiol Biochem 47:215–223PubMedCrossRefGoogle Scholar
- Dell’Agnola G, Nardi S (1987) Hormone-like effect and enhanced nitrate uptake induced by depolycondensed humic fractions obtained from Allolobophora rosea and A. caliginosa faeces. Biol Fertil Soils 4:115–118Google Scholar
- Desclos M, Dubousset L, Etienne P, Bonnefoy J, Lecahérec F, Satoh H, Ourry A, Avice JC (2008) A proteomic profiling approach to reveal a novel role of BnD22 (Brassica napus drought 22)/water soluble chlorophyll binding protein in young leaves during nitrogen remobilization induced by stressful condition. Plant Physiol 147:1830–1844PubMedCrossRefGoogle Scholar
- Etienne P, Desclos M, Le Gou L, Gombert J, Bonnefoy J, Maurel K, Le Dily F, Ourry A, Avice JC (2007) N-protein mobilization associated with the leaf senescence process in oilseed rape in concomitant with the disappearance of trypsin inhibitor activity. Funct Plant Biol 34:895–906CrossRefGoogle Scholar
- Krouk G, Lacombe B, Bielach A, Perrine-Walker F, Malinska K, Mounier E, Hoyerova K, Tillard P, Leon S, Ljung K, Zazimalova E, Benkova E, Nacry P, Gojon A (2010) Nitrate-regulated auxin transport by NRT1.1 defines a mechanism for nutrient sensing in plants. Dev Cell 18:927–937PubMedCrossRefGoogle Scholar
- Malagoli P, Laine P, Rossato L, Ourry A (2005) Dynamics of nitrogen uptake and mobilization in field-grown winter oilseed rape (Brassica napus L.) from stem extension to harvest. II A 15N-labelling based simulation model of N partitioning between vegetative and reproductive tissues. Ann of Bot 95:1187–1198CrossRefGoogle Scholar
- Mora V, Bacaicoa E, Zamarreno AM, Aguirre E, Garnica M, Fuentes M, Garcia-Mina JM (2010) Action of humic acid on promotion of cucumber shoot growth involves nitrate-related changes associated with the root-to-shoot distribution of cytokinins, polyamines and mineral nutrients. J Plant Physiol 167:633–642PubMedCrossRefGoogle Scholar
- Muscolo A, Panuccio MR, Abenavoli MR, Concheri G, Nardi S (1996) Effect of molecular complexity and acidity of earthworm faeces humic fractions on glutamate dehydrogenase, glutamine synthetase, and phosphoenolpyruvate carboxylase in Daucus carota άII cells. Biol Fertil Soils 22:83–88CrossRefGoogle Scholar
- Okazaki K, Kabeya Y, Suzuki K, Mori T, Ichikawa T, Matsui M, Nakanishi H, Miyagishima S (2009) The PLASTID DIVISION1 and 2 component of the chloroplast division machinery determine the rate of chloroplast division in land plant cell differentiation. Plant Cell 21:1769–1780PubMedCrossRefGoogle Scholar
- Swift RS (1996) Organic matter characterization. In: Sparks DL (ed) Methods of soil analysis Part 3 Chemical methods SSSA Book Ser5. SSSA, Madison, pp 1011–1069Google Scholar
- Trevisan S, Botton A, Vaccaro S, Vezzaro A, Quaggiotti S, Nardi S (2011) Humic substances affect Arabidopsis thaliana physiology by altering the expression of genes involved in primary metabolism, growth and development. Environ. Exp Bot doi: 10.1016/j.envexpbot.2011.04.017
- Zhang X, Schmidt RE (1997) The impact of growth regulators on the α-tocopherol status in water-stressed Poa pratensis. Int Turfgrass Soc Res J 8:1364–1371Google Scholar