Nitrogen nutrition index and leaf chlorophyll concentration and its relationship with nitrogen use efficiency in barley (Hordeum vulgare L.)

2017 ◽  
Vol 40 (8) ◽  
pp. 1190-1203 ◽  
Author(s):  
Christos Dordas
2016 ◽  
Vol 44 (2) ◽  
pp. 375-381 ◽  
Author(s):  
Hermann RESTREPO-DIAZ ◽  
Jorge BETANCOURT-OSORIO ◽  
Diego SANCHEZ-CANRO

Climate change has altered rainfall patterns causing waterlogging periods that often negatively affect the performance of horticultural crops in the Andean region in Colombia. An experiment was carried out under greenhouse conditions using three-month-old tamarillo (Solanum betaceum Cav.) seedlings, which were grown under two levels of nitrogen (N) (10 and 150 mg N∙L H2O). At 28 days after transplanting (DAT), waterlogging treatments were established when well-nourished plants (150 mg N L-1 H2O) significantly showed a higher shoot length than poor-nourished plants (10 mg N L-1 H2O) (~20 cm vs. ~10 cm, respectively). Three different periods of waterlogging were performed between 35 and 37, 51 and 55, and 64 and 70 DAT by covering the holes in the plastic pots to ensure a constant water depth. Results showed that well-nourished plants without waterlogging treatments through the experiment’s stress showed a greater shoot length (30 cm), total plant dry weight (7.95 g), Fv/Fm ratio (0.62) and leaf chlorophyll content (37.51 SPAD units) than poor-nourished plants without stress condition (15 cm, 5.57 g, 0.5 and 12.69 SPAD units, respectively) at the end of the experiment. Overall, waterlogging reduced leaf area and nitrogen use efficiency (about 75% and 50%, respectively) in both N levels. However, periods of waterlogging enhanced dry matter partitioning to stems (around 30-35%) in both N levels. This study showed that tamarillo plants are susceptible to landscaping situations where periods of waterlogging can be expected regardless of their N nutritional status.


Author(s):  
Mónica Liliana Garcia-Bañuelos ◽  
Esteban Sanchez ◽  
Alfonso Antero Gardea-Béjar ◽  
Ezequiel Muñoz-Marquez ◽  
Juan Manuel Soto-Parra ◽  
...  

The aim of the current study was to evaluate the performance of nitrogen (N) efficient use by ‘Fascinato’ (F), ‘Jannette’ (J), ‘Orangela’ (O), and ‘Sweet’ (S) cultivars grafted onto ‘Terrano’ (T) and ‘Robusto’ (R) rootstocks. Such evaluation was achieved by analyses of physiological and biochemical variables involved in N metabolism between grafted and ungrafted plants. Our findings point out that grafted ‘Fascinato’ cultivar (F/T) registered greatest relative leaf chlorophyll content, total chlorophyll concentration, a higher NR activity than did graft ‘Janette’ cultivar (J/T). In addition, these results reveal high significance with the interaction variety*date for these variables (relative leaf Chl, total Chl and NR activity), during the months of fruit yield of grafted bell pepper cultivars. This situation suggest than the effect of grafting under the increased of crop yield depend on the type of variety, as resulted with grafted ‘Fascinato’ cultivar.


Plants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1738
Author(s):  
Nirmal Sharma ◽  
Raquel Schneider-Canny ◽  
Konstantin Chekhovskiy ◽  
Soonil Kwon ◽  
Malay C. Saha

Wheat is a major cool-season forage crop in the southern United States. The objective of this study is to understand the effect of nitrogen (N) fertilization on wheat biomass yield, quality, nitrogen use efficiency (NUE), and nitrogen nutrition index (NNI). The experiments were conducted in a greenhouse and a hoop house in a split-plot design, with three replications. Twenty wheat cultivars/lines were evaluated at four N rates (0, 75, 150, and 300 mg N.kg−1 soil) in the greenhouse and (0, 50, 100, and 200 mg N.kg−1 soil) in the hoop house. In general, high-NUE lines had lower crude protein content than the low-NUE lines. None of the cultivars/lines reached a plateau for biomass production or crude protein at the highest N rate. The line × N rate interaction for NUE was not significant in the greenhouse (p = 0.854) but was highly significant in the hoop house (p < 0.001). NNI had a negative correlation with NUE and biomass. NUE had strong positive correlations with shoot biomass and total biomass but low to moderate correlations with root biomass. NUE also had a strong positive correlation with N uptake efficiency. Lines with high NUE can be used in breeding programs to enhance NUE in wheat for forage use.


Sign in / Sign up

Export Citation Format

Share Document