Interactive effects of nitrogen form and pH on growth, morphology, N uptake and mineral contents of Coix lacryma-jobi L.

2013 ◽  
Vol 111 ◽  
pp. 144-149 ◽  
Author(s):  
Arunothai Jampeetong ◽  
Dennis Konnerup ◽  
Narumol Piwpuan ◽  
Hans Brix
HortScience ◽  
2008 ◽  
Vol 43 (2) ◽  
pp. 575-579 ◽  
Author(s):  
Silvia Jiménez Becker ◽  
Maria Teresa Lao ◽  
Mari Luz Segura

Adjusting fertility programs according to peak demand periods will help prevent periodic nutrient disorders during crop growth, allowing enhanced use efficiency of water and fertilization. The objectives of this article were to investigate 1) the evolution of the changes in the concentration of nitrate and ammonium in the recycled solution with different N-NO3 –/N-NH4 + ratios; 2) the influence of the N form supply (N-NO3 – or N-NH4 +) on the nitrogen uptake, the nitrogen:water uptake ratio, and nitrogen use and uptake efficiency; and 3) the development of empirical models that would allow the prediction of nitrogen nutritional needs of Dieffenbachia amoena to increase the N use efficiency in a recycled system. To achieve these aims, N uptake has been correlated to climate parameters such as temperature, vapor pressure deficit and global radiation, and growth parameters such as leaf area index. The trial was carried out with Dieffenbachia amoena plants growing in a recycled system with expanded clay as substrate. The crop was placed in an INSOLE (Buried Solar Greenhouse), the plants being supplied with equal amounts of N, differing in the percentage of the N form applied (NO3 –:NH4 +): TA (100:0), TB (50:50), and TC (0:100). The nitrogen form generated important changes in the pH and nitrate and ammonium concentration in nutritive solution during the recirculating solution. In N-NO3 – treatment, pH increased and nitrate concentration showed a tendency to drop slightly. N-NH4 + treatment showed an abrupt N-NH4 + concentration decrease, and N-NO3 – concentration increased along with a pH drop. Also, the nitrogen form applied to the Dieffenbachia amoena crop affects nitrogen uptake. Nitrogen uptake rates and nitrogen uptake concentration were higher in the plants supplied with N-NH4 + or NO3 –+NH4 + than in the plants provided with N-NO3 – alone. The supply of a combination of 50:50 NO3 –+NH4 + improved the N use efficiency. The study also indicated the possibility of predicting the N uptake rate and N uptake concentration using the proposed models.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Seema Sahay ◽  
Luis Robledo-Arratia ◽  
Katarzyna Glowacka ◽  
Meetu Gupta

AbstractLittle is known about the interactive effects of exogenous nitric oxide (NO) and abscisic acid (ABA) on nitrogen (N) metabolism and related changes at molecular and biochemical levels under drought stress. The present study highlights the independent and combined effect of NO and ABA (grouped as “nitrate agonists”) on expression profiles of representative key genes known to be involved in N-uptake and assimilation, together with proline metabolism, N–NO metabolism enzyme’s activity and nutrient content in polyethylene glycol (PEG) treated roots of Indian mustard (B. juncea cv. Varuna). Here we report that PEG mediated drought stress negatively inhibited growth performance, as manifested by reduced biomass (fresh and dry weight) production. Total N content and other nitrogenous compounds (NO3−, NO2−) were decreased; however, NH4+, NH4+/ NO3− ratio and total free amino acids content were increased. These results were positively correlated with the PEG induced changes in expression of genes and enzymes involved in N-uptake and assimilation. Also, PEG supply lowered the content of macro- and micro-nutrients but proline level and the activity of ∆1-pyrroline-5-carboxylate synthetase increased indicating increased oxidative stress. However, all these responses were reversed upon the exogenous application of nitrate agonists (PEG + NO, PEG + NO + ABA, and PEG + ABA) where NO containing nitrate agonist treatment i.e. PEG + NO was significantly more effective than PEG + ABA in alleviating drought stress. Further, increases in activities of L-arginine dependent NOS-like enzyme and S-nitrosoglutathione reductase were observed under nitrate agonist treatments. This indicates that the balanced endogenous change in NO and ABA levels together during synthesis and degradation of NO mitigated the oxidative stress in Indian mustard seedlings. Overall, our results reveal that NO independently or together with ABA may contribute to improved crop growth and productivity under drought stress.


Horticulturae ◽  
2021 ◽  
Vol 7 (8) ◽  
pp. 260
Author(s):  
Reda. M. Y. Zewail ◽  
Maha Ali ◽  
Ibrahim S. H. El-Gamal ◽  
Sherine H. A. Al-Maracy ◽  
Khandakar R. Islam ◽  
...  

Stevia (Stevia rebaudiana, L.) is receiving increasing global interest as a diabetes-focused herb associated with zero-calorie stevioside sweetener glycoside production. This study was conducted to determine whether the arbuscular mycorrhiza (AM), as a biofertilizer integrated with nano boron (B), zinc (Zn), and molybdenum (Mo), would improve stevia growth and stevioside content. A factorial experiment with four replicates was conducted to evaluate the effect of AM at 0, 150, and 300 spore/g soil and three nano microelements B at 100 mg/L, Zn at 100 mg/L, and Mo at 40 mg/L on growth performance, stevioside, mineral contents, and biochemical contents of stevia. Results indicated that the combination of AM at 150 and B at 100 mg/L significantly increased plant height, number of leaves, fresh and dry-stem, and herbal g/plant during the 2019 and 2020 growing seasons. Chlorophyll content was increased by the combination between AM at 150 spore/g soil and B at 100 mg/L during both seasons. Stevioside content in leaves was increased by AM at 150 spore/g soil and B at 100 mg/L during the second season. In addition, N, P, K, Zn, and B in the leaf were increased by applying the combination of AM and nano microelements. Leaf bio constituent contents were increased with AM at 150 spore/g soil and B at 100 mg/L during both seasons. The application of AM and nano B can be exploited for high growth, mineral, and stevioside contents as a low-calorie sweetener product in stevia.


Author(s):  
Tadesse Debele ◽  
Birhanu Iticha

Nitrogen is the most limiting plant nutrient in Vertisols in western Ethiopia. Vertisols properties and management factors as well as fertilizer source and time of application could influence nutrient uptake by crops. With this view, a field study was conducted at Ambo Agriculture Research Centre experimental site during the main cropping season of 2013- 2014, with the aim to determine interactive effects of drain depth of Vertisols, N source and time of N application on nutrient uptake by maize. Treatments comprised five drain depths (0, 15, 30, 45 and 60 cm), two N sources (urea and ammonium sulfate) and two timings of N applications (twice and thrice). The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. Result showed that there was significant interactions effect of drain depths, N source and time of application on the concentration of nutrients in the grain and stover. The NH4-N uptake by maize was found to be significantly better than NO3-N utilization by maize. Grain and stover uptake of N, P and K by maize increased with drain depth and thrice split application of ammonium sulfate. It is concluded that draining off excess soil water from the rhizosphere is the key factor in improving nutrient uptake by maize in Vertisols in Ambo area.Int. J. Agril. Res. Innov. & Tech. 7 (1): 1-7, June, 2017


Sign in / Sign up

Export Citation Format

Share Document