Plant morphophysiological and anatomical factors associated with nitrous oxide flux from wheat (Triticum aestivum)

Abstract

Experiments were conducted to study the dynamics of nitrous oxide (N₂O) emission from wheat varieties viz., Sonalika, HUW 468, HUW 234 and DBW 14 grown in alluvial soils of North Bank Plain Agroclimatic Zone of Assam, India. Attempts were made to find out the relationship of N₂O emission with plant morphophysiological, anatomical and soil properties. N₂O fluxes from wheat varieties ranged from 40 μg N₂O-N m⁻² h⁻¹ to 295 μg N₂O-N m⁻² h⁻¹. Soil organic carbon and soil temperature have shown significant relationship with N₂O flux. The rate of leaf transpiration recorded from the wheat varieties at different growth stages exhibited a positive correlation with N₂O emission suggesting that movement of N₂O along with the transpirational water flow may be an important mechanism of N₂O transport and emission through wheat plants. Anatomical investigation by scanning electron microscope revealed that N₂O emission has relationship with stomatal frequency of leaf and leaf sheaths. Variety HUW 234 with the highest stomatal frequency of leaf and leaf sheath also recorded higher seasonal N₂O emission compared to other varieties. Seasonal N₂O emission (E(sif)) of the varieties ranged from 3.25 to 3.81 kg N₂O-N ha⁻¹. Significant variations in E(sif) values were recorded within the varieties.

Effect of organic amendments with varied C-N ratios on grain productivity and nitrous oxide (N2O) emission from wheat grown in alluvial soil

“…In our study we report a strong correlation of N 2 O emission with soil organic carbon and mineral N (NH 4 + and NO 3 -). There are reports that an increase in soil organic carbon provides the carbon source to the microbial populations for carrying out nitrification and denitrification reactions, which influences the N 2 O emission (Tiedje et al, 1982;Baruah et al, 2012). Similar results have been corroborated by Huang et al, 2004;Toma and Hotana, 2007. In consequence to high C-N ratio, the microbes immobilize the soil nitrogen during the decomposition of residues.…”

Response surface methodology based optimization of cadmium and lead remediation from aqueous solution by water hyacinth (Eichhornia crassipes [Mart.] Solms) and its anatomical study

“…The process of bioremediation continues until an equilibrium is established between the amount of toxicant sorbate species and its portion remaining in the solution (Mahmood et al, 2010). Earlier studies of aquatic plants also stated that toxicant acts as an on/off switch for stomata (Baruah et al, 2012;Iida et al, 2016). Hyperaccumulating aquatic plants like water hyacinth (Eichhornia crassipes), water caltrop (Trapa natans) and water lettuce (Pistia stratiotes) which are capable to remove heavy metals from contaminated water bodies commonly known as phytoremediation of heavy metals from wastewaters (Liao and Chang, 2004;Deka and Sarma, 2011;Kumar et al, 2017a;Kumar et al, 2018).…”

Changes in organic carbon pool in a tropical soil planted to rice in relation to photosynthetic carbon fixation

“…The soil samples were collected from various locations of the experimental area, and then three composite samples were prepared as representatives of the plot. The physico-chemical properties of the initial soil samples (soil texture, p H , bulk density, available N, available P and available K) collected prior to the start of the experiment, were analyzed by the methods of Baruah et al, (2012). Soil samples from 0 -15cm soil layer were collected at tillering, panicle initiation, 50 % flowering and at harvest for analyzing SOC changes during the growth period of the rice crop during 2012, 2013 and 2014.…”