Physiological and molecular responses in tomato under different forms of N nutrition

Genetic variation in eggplant for Nitrogen Use Efficiency under contrasting NO3‐ supply

“…Among physiological traits, NUtE was more influenced by genotype than NUE and NUpE. According to these results, NUtE was recently demonstrated more determinant than NUpE in NUE features in tomato (Abenavoli et al 2016; Lupini et al 2017), representing a useful trait to improve the utilization efficiency in Solanaceae. Therefore, it is noteworthy that the ability to utilize nitrate (NUtE) showed a significant phenotypic variation due to the genetic variance, underlined a rather high heritability (Table ).…”

“…Among physiological traits, NUtE was more influenced by genotype than NUE and NUpE. According to these results, NUtE was recently demonstrated more determinant than NUpE in NUE features in tomato Lupini et al 2017), representing a useful trait to improve the utilization efficiency in Solanaceae. Therefore, it is noteworthy that the ability to utilize nitrate (NUtE) showed a significant phenotypic variation due to the genetic variance, underlined a rather high heritability (Table 1) Through the hierarchical clustering, the pair of Nuse efficient/inefficient genotypes AM222/AM22 based on their different origin (Turkey vs. China), genetic distance (Cericola et al 2013) and their extreme contrasting root traits, were selected.…”

“…Differential gene expression levels among the contrasting genotypes on the nitrate transporters SmNPF6.3 and SmNRT2.1 involved in root formation and acquisition (Garnet et al 2009), confirmed the role of root system to confer N‐use efficiency (Figure ). Indeed, root size plays a critical role in nutrient uptake in tomato (Abenavoli et al 2016; Lupini et al 2017), maize (Li et al 2015) and rapeseed (Wang et al 2017). In eggplants, the N‐key gene expression and enzyme activities highlighted a strong correlation with N‐efficiency.…”

“…Five plants (28 days old) for each genotype, exposed to LN and HN for 18 days, were collected and divided into shoots and roots. Roots were dipped in 0.1% (w/v) toluidine blue (Sigma Aldrich, #89160) for 5 min and then scanned at 300 dpi resolution (WinRhizo STD 1600, Instruments Règent Inc., Quebec, Canada) to determine primary (PRL; cm), lateral (LRL; cm) and total root length (TRL; cm), and volume (cm 3 ) using WinRhizo Pro System v. 2002a software (Lupini et al 2016, 2017). Lateral root number (LRN, #) was manually counted as reported by Lupini et al (2014).…”

“…Shoots and roots were then dried at 72°C for 48 h to determine their dry weight (SDW and RDW, respectively, g). Based on the above measurements, Root length ratio (RLR, root length/whole dry weight, cm g ‐1 ), root mass ratio (RMR, root dry weight/whole dry weight, g g ‐1 ), specific root length (SRL, root length/root dry weight, cm g ‐1 ), root fineness (RF, root length/root volume, cm cm ‐3 ), and root tissue density (RTD, root dry weight/root volume, g cm ‐3 ) were also calculated (Lupini et al 2016, 2017).…”