Effect Of Nitrogen Form Research Articles

Effects of Nitrogen Forms on the Growth and Nitrogen Accumulation in Buchloe dactyloides Seedlings.

Buffalograss [Buchloe dactyloides (Nutt.) Engelm.] has become the most widely cultivated warm-season turfgrass in northern China because of its low-maintenance requirements. Nitrogen (N) can be applied to plants in a range of formulations. However, preference of nitrogen uptake and the effects of N form on plant growth and nitrogen accumulation has not been established in buffalograss. In this study, we evaluated the effects of different inorganic nitrogen forms (NO3−-N, NH4+-N, and NO3−-N: NH4+-N = 1:1) on growth and nitrogen accumulation in buffalograss seedlings. Results showed that supply of three N forms significantly increased buffalograss seedlings growth, biomass, and N contents of all plant organs compared with the seedlings receiving free nitrogen. Plants achieved better growth performance when they received nitrate as the sole N source, which stimulated stolon growth and increased the biomass of ramets, spacers, and aboveground and total plant biomass, and also allocated more biomass to ramets and more N to spacers. Meanwhile, those plants supplied with the treatment +NH4NO3 displayed a significantly greater N content in the ramet, 15N abundance, and 15N accumulation amount in all organs. These data suggest NO3−-N supplied either singly or in mixture increased vegetative propagation and thus facilitates buffalograss establishment. However, applications of ammonium caused detrimental effects on buffalograss seedlings growth, but +NO3− could alleviate NH4+-induced morphological disorders. Thus, recommendations to increase vegetative propagation and biomass accumulation in buffalograss seedlings should consider increasing NO3−-N in a fertility program and avoiding applications of nitrogen as NH4+-N.

Nitrogen induced DOC and heavy metals leaching: Effects of nitrogen forms, deposition loads and liming

Atmospheric nitrogen (N) deposition is believed to accelerate dissolved organic carbon (DOC) production and could lead to increased heavy metal mobility into water resources. We sampled intact soil cores from the Isle of Skye with low background N deposition history and having Serpentine rock known for its higher heavy metal concentrations including zinc (Zn), copper (Cu), nickel (Ni) and lead (Pb). The effects of 16 (16kgN) and 32 kg N ha−1 year−1 (32kgN), and liming with 32kgN (32kgN+Lime) on soil solution chemistry and heavy metal mobilization were investigated over the 15-month study. Nitrogen in deposition load was added at five ammonium (NH4+) to nitrate (NO3−) ratios of 9:1, 5:1, 1:1, 1:5 and 1:9 along NO3−dominance. We found significant effects of load on Cu and NH4+/NO3− ratio on pH, DOC and Zn in soil solution. However, under lime and ratio experimental factors, liming significantly influenced pH, DOC, Cu and Pb, and NH4+/NO3− ratio pH, DOC, Ni and Zn whereas interactions between lime and ratio was significant for Ni and Cu. pH and DOC increased with N load, liming and NO3− dominance, and both correlated significantly positively. Liming under NH4+ dominance enhanced DOC production due to supply of base cations in lime. Mobilization of Cu, Ni and Pb was driven by DOC concentrations and, therefore, increased with load, liming and NO3− dominance in deposition. However, in contrast, low pH and high NH4+ dominance was associated with Zn mobilization in soil solution. On the contrary, despite of some patterns, heavy metals in soil HNO3 extracts were devoid of any load, lime and NH4+/NO3− ratio effects. Our study suggests that the effects of N load and forms in deposition on sites with high accumulated loads of metals need to be better quantified through soil solution partitioning models.

The different effects of nitrogen forms (NH4+ and NO3-) on cell wall phosphorus remobilization in rice

The different effects of nitrogen forms (NH4+ and NO3-) on cell wall phosphorus remobilization in rice

Effects of nitrogen forms on carbohydrate metabolism and storage‐root formation of sweet potato

AbstractIn this study, we examined the effects of different forms of nitrogen (N) fertilizer on carbohydrate metabolism and storage root formation in sweet potato [Ipomoea batatas L. (Lam.) cv. Shangshu 19 and cv. Jixu 23] in 2015–2016. Two fertilizer treatments, ammonium nitrogen (AN) and amide nitrogen (XN), were applied at 60 kg ha−1 in a two‐factor split‐plot design. The effects of nitrogen form on the morphology of adventitious roots, carbohydrate metabolism in potential storage roots, and number of storage roots per plant in sweet potato were investigated. The results show that during the early growth phase, the AN treatment significantly increased the number of adventitious roots, root tips, root length density, and fresh weight of roots (in pot trials). This treatment also significantly decreased the sucrose concentration of potential storage roots and increased the activities of cell wall, vacuolar, and cytoplasmic invertases. However, XN‐treated potential storage roots showed a relatively high starch concentration, activities of sucrose synthase and ADP‐glucose pyrophosphorylase, and transcription of sporamin genes. At the canopy closure period, the AN treatment significantly increased the number of storage roots of 0.5–5.0 cm in diameter and decreased the number of those > 5 cm in diameter compared to the control. The XN treatment induced the opposite effects. In the harvesting period, the AN treatment produced the highest storage root yield and number of storage roots per plant. Thus, in field trials the AN treatment induced a greater increase in production by increasing the number of storage roots.

Effects of nitrogen form on accumulation of alkaloids and expression of relative genes in Atropa belladonna

Hyoscyamine and scopolamine are two main alkaloids in Atropa belladonna with great medicinal value. In this paper, the contents of hyoscyamine and scopolamine, the upstream products in alkaloid synthesis, and the expression levels of key enzyme genes PMT, TRⅠ and H6H in secondary metabolism of A. belladonna seedlings were measured to clarify the mechanism of nitrogen forms regulating alkaloids synthesis.The results showed that the 50/50 (NH⁺₄/NO⁻₃) treatment was more favorable for the accumulation of alkaloids and the conversion of hyoscyamine to scopolamine. The content of putrescine was almost consistent with the change of key enzymes activities in the synthesis of putrescine, they both increased with the rise of ammonium ratio, reaching the highest at 75/25 (NH⁺₄/NO⁻₃). The detection of signaling molecule nitric oxide (NO) showed that the NO concentration decreased with the decrease of nitrate proportion. Further detection of gene expression levels of PMT, TRⅠ and H6H in TAs synthesis pathway showed that a certain amount of ammonium promoted the expression of PMT and H6H in roots. When the ratio of ammonium to nitrate was 50/50, PMT, TRⅠ and H6H in leaves and roots had higher expression levels. It can be speculated that the regulation of the formation of hyoscyamine to scopolamine by nitrogen forms mainly through affecting the expression of key enzyme genes. 50/50 (NH⁺₄/NO⁻₃) treatment increased the gene expression of TRⅠ in both leaves and roots as well as PMT and H6H in roots, promoting the synthesis of putrescine to hyoscyamine and the conversion of hyoscyamine to scopolamine.

Effect of Nitrogen Form on pH of Flooded Water by Photosynthesis of Periphyton on the Soil Surface

Effect of Nitrogen Form on pH of Flooded Water by Photosynthesis of Periphyton on the Soil Surface

Root ABA Accumulation Enhances Rice Seedling Drought Tolerance under Ammonium Supply: Interaction with Aquaporins.

In previous studies, we demonstrated that ammonium nutrition enhances the drought tolerance of rice seedlings compared to nitrate nutrition and contributes to a higher root water uptake ability. It remains unclear why rice seedlings maintain a higher water uptake ability when supplied with ammonium under drought stress. Here, we focused on the effects of nitrogen form and drought stress on root abscisic acid (ABA) concentration and aquaporin expression using hydroponics experiments and stimulating drought stress with 10% PEG6000. Drought stress decreased the leaf photosynthetic rate and stomatal conductivity and increased the leaf temperature of plants supplied with either ammonium or nitrate, but especially under nitrate supply. After 4 h of PEG treatment, the root protoplast water permeability and the expression of root PIP and TIP genes decreased in plants supplied with ammonium or nitrate. After 24 h of PEG treatment, the root hydraulic conductivity, the protoplast water permeability, and the expression of some aquaporin genes increased in plants supplied with ammonium compared to those under non-PEG treatment. Root ABA accumulation was induced by 24 h of PEG treatment, especially in plants supplied with ammonium. The addition of exogenous ABA decreased the expression of PIP and TIP genes under non-PEG treatment but increased the expression of some of them under PEG treatment. We concluded that drought stress induced a down-regulation of aquaporin expression, which appeared earlier than did root ABA accumulation. With continued drought stress, aquaporin expression and activity increased due to root ABA accumulation in plants supplied with ammonium.

Effects of nitrogen form of nutrient solution on uptake and concentration macro element and morphological trait in hydroponic tulip

ABSTRACTEffects of nutrient solution composition ratio on (Tulipa gesneriana L.) cv, ʹApricot Parrotʹ and ʹDaytonaʹ growth and flowering were studied hydroponics. Plants were grown with five treatments respectively: S1(0), S2(0.01), S3(0.02) S4(0.03) and S5(0.04) meq L.-1 ammonium or 0,0.38, 0.74, 0.11 and 0.14 ammonium (NH4+)/NH4+nitrate (NO3)−ratios. Flowering was accelerated by increase of ammonium level for both cultivars. Nutrition solution was not significant on the stem length of Daytona cultivar, but maximum flowering stem length occurred S2 solution for Apricot Parrot cultivar. Increasing ammonium level, decreased potassium concentration in the aerial parts. Total nitrogen of new bulbs decreased with increasing ammonium level for both cultivars. Maximum bulblet production rate occurred in plants that were fed with S5 solution. Maximum flower longevity was in S2 solution for both cultivars. growth and quality of tulip were affected by ammonium level in nutrient solution, so for obtain the best flower quality must added to nutrient solution.

Effects of Nitrogen Form and Its Application Time on Plant Growth and Tuber Yield of Potato

Effects of Nitrogen Form and Its Application Time on Plant Growth and Tuber Yield of Potato

Effect of nitrogen form (ammonium and nitrate) on quantitative and qualitative indices of Tulipa gesneriana cv. Apricot parrot

Effects of nutrient solutions on quantitative and qualitative indices of tulip (Tulipa gesneriana cv. Apricot parrot) were studied in a completely randomized design with 5 nutrient solutions, 4 experimental units and 3 replications. Plants were fed with five nutrient solutions (S1, S2, S3, S4 and S5) having NH4 -N/total N ratios of 0, 0.038, 0.074, 0.11 and 0.14, respectively. All nutrient solutions had similar concentrations of mineral elements. The five treatments consisted of 2.5 meq/L total N, and concentration of all the nutrients was 8.4 meq/L. Based on the results, increasing the ammonium level in nutrient solutions decreased N and total protein storage in the bulbs, but increased N concentration in the shoots. The ammonium level had no significant effect on potassium concentration of shoots, but increased phosphorus concentration in the shoots. Maximum calcium and magnesium concentration in shoots, wet weight and length and diameter of flowering stem were obtained in plants fed with S2 solution. Increasing the ammonium level increased number of bulblets, but decreased their size. Increasing the ammonium level decreased time to flowering of bulbs. The highest longevity of cut flowers was observed in plants fed with S2 solution. In general, based on the results of this research, with increasing the ammonium level in the nutrients solution, the qualitative traits of tulip, such as length and diameter of flowering stem, were increased, but longevity of cut flowers and number of produced bulblets were decreased.

The effects of nitrogen form on root morphological and physiological adaptations of maize, white lupin and faba bean under phosphorus deficiency.

Root morphological/physiological modifications are important for phosphorus (P) acquisition of plants under P deficiency, but strategies differ among plant species. Detailed studies on the response of maize roots to P deficiency are limited. Nitrogen (N) form influences root morphology/physiology, and thus may influence root responses to P deficiency. This work investigated adaptive mechanisms of maize roots to low P by comparison with white lupin and faba bean supplied with two N forms. Plants were grown for 7–16 days in hydroponics with sufficient (250 µmol L−1) and deficient P supply (1 µmol L−1) under supply of NH4NO3 or Ca(NO3)2. Plant growth and P uptake were measured, and release of protons and organic acid anions, and acid phosphatase activity in the root were monitored. The results showed that P deficiency significantly decreased shoot growth while increased root growth and total root length of maize and faba bean, but not white lupin. It enhanced the release of protons and organic acid anions, and acid phosphatase activity, from the roots of both legumes but not maize. Compared with Ca(NO3)2, NH4NO3 dramatically increased proton release by roots but did not alter root morphology or physiology of the three species in response to low P. It is concluded that the N form did not fundamentally change root morphological/physiological responses of the three species to P deficiency. Morphological variation in maize and morpho-physiological modifications in white lupin and faba bean were the main adaptive strategies to P deficiency.

Comparative Effect of Nitrogen Forms on Nitrogen Uptake and Cotton Growth Under Salinity Stress

The effects of nitrogen (N) forms (ammonium- or nitrate-N) on plant growth under salinity stress [150 mmol sodium chloride (NaCl)] were studied in hydroponically cultured cotton. Net fluxes of sodium (Na+), ammonium (NH4+), and nitrate (NO3−) were also determined using the Non-Invasive Micro-Test Technology. Plant growth was impaired under salinity stress, but nitrate-fed plants were less sensitive to salinity than ammonium-fed plants due mainly to superior root growth by the nitrate-fed plants. The root length, root surface area, root volume, and root viability of seedlings treated with NO3-N were greater than those treated with NH4-N with or without salinity stress. Under salinity stress, the Na+ content of seedlings treated with NO3-N was lower than that in seedlings treated with NH4-N owing to higher root Na+ efflux. A lower net NO3− efflux was observed in roots of nitrate-fed plants relative to the net NH4+ efflux from roots of ammonium-fed plants. This resulted in much more nitrogen accumulation in different tissues, especially in leaves, thereby enhancing photosynthesis in nitrate-fed plants under salinity stress. Nitrate-N is superior to ammonium-N based on nitrogen uptake and cotton growth under salinity stress.

Effects of nitrogen form on growth and quality of Chrysanthemums morifolium

This paper is aimed to study the effects of nitrogen form on the growth and quality of Chrysanthemums morifolium at the same nitrogen level. In order to provide references for nutrition regulation of Ch. morifolium in field production, pot experiments were carried out in the greenhouse at experimental station of Nanjing Agricultural University. Five proportions of ammonium and nitrate nitrogen were set up and a randomized block design was applied four times repeatedly. The results showed that the growth and quality of Ch. morifolium were significantly influenced by the nitrogen form. The content of chlorophyll and photosynthesis rate were the highest at the NH4(+) -N /NO3(-) -N ratio of 25:75; The activities of NR in different parts of Ch. -morifolium reached the highest at the NH4(+) - N/NO3(-) -N ratio of 0: 100. The contents of nitrate nitrogen in the root and leaves reached the highest at the NH4(+) -N/NO3(-) -N ratio of 50:50. The activities of GS, GOGAT and the content of amylum increased with the ratio of NO3(-) -N decreasing and reached it's maximum at the NH4 + -N/NO3 - -N ratio of 100: 0. The content of ammonium nitrogen were the highest at the NH4 + -N /NO3 --N ratio of 75: 25, while the content of soluble sugar reached the highest at the NH4(+)-N/NO3(-) -N ratio of 25: 75. The content of flavones, chlorogenic acid and 3,5-O-dicoffeoylqunic acid were 57.2 mg x g(-1), 0.673% and 1.838% respectively, reaching the maximum at the NH4(+) -N /NO3(-) -N ratio of 25:75; The content of luteoloside increased with the ratio of NO3(-) -N increasing and reached it's maximum at the NH4(+) -N/NO3(-) -N ratio of 0: 100. The yield of Ch. morifolium reached it's maximum at the NH4(+) -N /NO3(-) -N ratio of 25:75. Nitrogen form has some remarkable influence on the nitrogen metabolism, photosynthesis and growth, Nitrogen form conducive to the growth and quality of Ch. morifolium at the NH4(+) -N /NO3(-) -N ratio of 25: 75.

Effects of Nitrogen Form in Nutrient Solution on Passion Fruit Quality

Effects of Nitrogen Form in Nutrient Solution on Passion Fruit Quality

Effects of Nitrogen Form and Concentration in Fertilizer on Vegetative Growth, Flowering, and Leaf Mineral Contents of Passion Fruit

Effects of Nitrogen Form and Concentration in Fertilizer on Vegetative Growth, Flowering, and Leaf Mineral Contents of Passion Fruit

Effects of Nitrogen Form and Application Rates on the Growth of Petunia and Nitrogen Content in the Substrate

Fertigation practices have been proposed for decreasing nitrogen (N) leaching losses and for nutrient efficiency increase, including the use of nutrient solutions with low concentrations of N and the application of nitrification inhibitors with ammonium ammonium (NH4 +) N fertilizers. The effects of N form, application rates, and use of an inhibitor of nitrification [3,4- dimethylpyrazole phosphate (DMPP)] on the growth and the N percentages in leaves of Petunia × hybrida, as well as the N content in the substrate, were tested. Plants were placed in a venlo-glass greenhouse. Five treatments were established, changing N form, application rates, and with or without the inhibitor of nitrification: T1, 120 mg L−1 of N- nitrate (NO3 −); T2, 120 mg L−1 of N-NH4 +; T3, 80 mg L−1 of N-NH4 + with DMPP; T4, 120 mg L−1 of N-NH4 + with DMPP; and T5, 160 mg L−1 of N-NH4 + with DMPP. Nitrogen form did not have an effect on plant dry and fresh weight, plant height, or number of buds; however, ammonium treatments increased ammonium concentration and reduced nitrate concentration in the substrate solution. The use of DMPP achieved a significant reduction in nitrate concentrations in the substrate solution. Nitrogen percentage in leaves was not affected by N form, whereas the leaves of the plants treated with ammonium showed an increase in color, probably due to an increase in iron concentration. Ammonium fertilization increased the percentage of plants that survived in dark storage conditions.

Effects of nitrogen forms and ratios on photosynthetic characteristics of Newhall navel orange in calcareous yellow soils

采用盆栽方法, 在避雨透光棚内, 研究不同形态氮源及其配比[NO₃^--N∶NH₄⁺-N=100∶0(硝酸钙42.16 g·盆^-1)、NO₃^--N∶NH₄⁺-N=75∶25(硝酸钙31.62 g·盆^-1, 碳酸氢铵7.06 g·盆^-1)、NO₃^--N∶NH₄⁺-N= 50∶50(硝酸钙21.08 g·盆^-1, 碳酸氢铵14.12 g·盆^-1)、NO₃^--N∶NH₄⁺-N=25∶75(硝酸钙10.54 g·盆 ^-1, 碳酸氢铵21.19 g·盆^-1)、NO₃^--N∶NH₄⁺-N=0∶100(碳酸氢铵28.25 g·盆^-1)、尿素10.71 g·盆^-1]对枳砧纽荷尔脐橙叶片光合速率(Pn)日变化、光合色素含量、叶片光补偿点和光饱和点的影响, 为柑橘的氮素营养及施肥管理提供科学依据。结果表明: NO₃^--N∶NH₄⁺-N为75∶25处理的脐橙叶片中叶绿素a(Chl. a)、叶绿素b(Chl. b)和类胡萝卜素(Car.)含量和全天Pn都显著或极显著高于其他氮源配比处理, 上午10:00脐橙叶片的Pn、Tr、WUE和Gs均是最高的, 极显著高于其他氮源处理, 其Pn、Tr、WUE和Gs分别为4.81 μmol(CO2)·m^-2·s^-1、2.30 mmol(H2O)·m^-2·s^-1、2.09和0.09 mol·m^-2·s^-1。随着NH₄⁺-N比例的增加, 脐橙叶片中Chl. a、Chl. b和Car.的含量与Pn、Tr、WUE和Gs均逐渐下降。100% NO₃^--N处理的脐橙叶片Pn也极显著低于NO₃^--N∶NH₄⁺-N为75∶25处理, 其Pn仅为3.53 μmol(CO2)·m^-2·s^-1。单一尿素氮处理(施用10.71 g·盆^-1尿素)的脐橙叶片中Chl. a、Chl. b、Car.和Pn含量最低, 其Pn为3.07 μmol(CO2)·m^-2·s^-1, 与单纯施用NH₄⁺-N处理无显著性差异。不同氮源处理的脐橙叶片光饱和点和光补偿点均无显著性差异, 其值分别维持在861.51 μmol·m^-2·s^-1和10.09 μmol·m^-2·s^-1左右。NO₃^--N和NH₄⁺-N混合比例为75∶25时有利于提高纽荷尔脐橙Pn。

Effect of Nitrogen Form on Gene Expression in Leaf Tissue of Greenhouse Grown Potatoes During Three Stages of Growth

This study examined the expression of genes in leaf tissue of greenhouse-grown potatoes to the form of N supplied in the context of development of a diagnostic tool for detection of N status. Potato cultivar ‘Shepody’ was grown over a two-week period at three stages of growth (tuber initiation, flowering and early tuber bulking) with three forms of N (NO3− only, NH4+ only, or 1:1 NO3−:NH4+) at two levels of N supply (0.75 or 7.5 mM). Leaf disks were collected and extracted for RNA, and 28 genes examined for expression using nCounter. Expression of ammonium transporter AT1 was increased when the N supply was reduced, regardless of N form, and was generally independent of growth stage. Expression of AT1 was less influenced by N form than currently used chemical or optical measures of plant N status. Expression of AT1 can be used as a quantitative indicator for plant N status of potato regardless of nitrogen form and crop growth stage.

Effect of Nitrogen Form on the Effectiveness of a Phosphate-Solubilizing Fungus to Dissolve Rock Phosphate

An in vitro experiment was carried out to evaluate the effect of nitrogen (N) form (NH4+ and/or NO3-) on the dissolution of rock phosphate (RP) by a phosphate solubilizing fungus (PSF) identified as Mortierella sp. In the presence of NH4Cl or NH4NO3, the solution of pH significantly decreased from an initial value of 7.6 to 3.4 and 3.7 respectively. In the presence of KNO3, the pH went down only to 6.7. As a result, significantly more P was detected in solution in the presence of NH4Cl (129.65 mg/L) than in the presence of NH4NO3 (109.25 mg/L). The concentration of P in solution in the presence of KNO3 was only 0.08 mg/L. The excess of NH4+ adversely affected the growth of Mortierella sp. However, this may have promoted a more active H+-pumping that decreased solution’s pH. In the presence of NO3- as the only source of N, Mortierella sp. not only dissolved a small amount of Pi from the RP but also immobilized most of it into its mycelia. In contrast, in the presence of NH4Cl, Mortierella sp. was effective to dissolve RP and the Pi released remaining in solution while only a little portion was immobilized by the fungal mycelia.

In vivo speciation of zinc in Noccaea caerulescens in response to nitrogen form and zinc exposure

Nitrate has been shown to enhance Zn hyperaccumulation in the shoots of Noccaea caerulescens (formerly Thlaspi caerulescens) (Prayon); however, the mechanisms beyond the effect of nitrogen form are unknown. This study used synchrotron X-ray absorption near-edge spectroscopy (XANES) on alive and intact plants at room temperature to examine whether enhanced Zn hyperaccumulation in nitrate-fed plants was associated with differences in Zn speciation, and to correlate Zn species with mechanisms of Zn uptake, translocation and hyperaccumulation. The higher Zn concentration in plants supplied with nitrate compared to ammonium, or with high Zn exposure (300 μΜ), was not due to differences in Zn speciation. The importance of carboxylates for Zn hyperaccumulation in the shoots was supported by a predominance of Zn-malate or Zn-citrate. Zinc-phytate was detected for the first time in this species and may assist Zn-tolerance in the roots. The feasible presence of Zn-histidine in the roots but not in the xylem sap suggests a mechanism for Zn binding and non-toxic transport through the cytoplasm and release of aqueous Zn into the xylem vessels. Zinc was translocated in the xylem as Zn-malate and weakly complexed or aqueous Zn forms. Zinc speciation in roots, shoots and xylem did not differ between nitrate- and ammonium-fed plants.