The response of juvenile and small adult western juniper (Juniperus occidentalis) to nitrate and ammonium fertilization

1991 ◽  
Vol 69 (11) ◽  
pp. 2344-2352 ◽  
Author(s):  
P. M. Miller ◽  
L. E. Eddleman ◽  
J. M. Miller
Keyword(s):  
Carbon Dioxide ◽  
Carbon Dioxide Assimilation ◽  
Negative Effects ◽  
Foliar Nitrogen ◽  
Juniperus Occidentalis ◽  
Nitrate N ◽  
Ammonium N ◽  
Nitrogen Concentrations ◽  
Use Efficiency ◽  
N Treatment

Effects of nitrate-N and ammonium-N fertilization on foliar nitrogen concentrations, carbon dioxide assimilation, leaf conductance, transpiration, intercellular carbon dioxide, xylem pressure potentials, specific leaf mass, and growth were measured on naturally established juvenile and small adult Juniperus occidentalis growing in central Oregon where ammonium-N was the dominant form of soil nitrogen throughout the summer. Fertilization with both forms of nitrogen increased foliar nitrogen concentrations in juveniles and small adults in May; concentrations in small adult foliage from the nitrate-N treatment were still higher than controls in September. Both forms of nitrogen reduced carbon dioxide assimilation and potential photosynthetic nitrogen-use efficiency. The negative relationship between nitrogen addition and carbon dioxide assimilation was more apparent in juveniles than in small adults; negative effects were more pronounced in the ammonium-N treatment than in the nitrate-N treatment. Leaf conductance and transpiration were also reduced, but reductions of water loss were greater than were negative effects of fertilization on carbon gain; thus water-use efficiency of juvenile and small adults increased in May and July. The depression in gas exchange processes was detectable for a longer period during the summer in juveniles than in small adult J. occidentalis. Branchlet elongation of juvenile and small adult J. occidentalis was increased with nitrate-N and ammonium-N addition, but variability reduced significance levels. Juniperus occidentalis appears to be adapted to utilize low, ambient levels of soil nitrate at the research site and did not preferentially utilize ammonium. Key words: gas exchange, water relations, foliar nitrogen, growth.

The response of western juniper (Juniperusoccidentalis) to reductions in above-and below-ground tissue

1991 ◽  
Vol 21 (2) ◽  
pp. 207-216 ◽  
Author(s):  
P. M. Miller ◽  
L. E. Eddleman ◽  
J. M. Miller
Keyword(s):  
Carbon Dioxide ◽  
Water Use ◽  
Lateral Roots ◽  
Nitrogen Concentration ◽  
Carbon Dioxide Assimilation ◽  
Ground Tissue ◽  
Photosynthetic Nitrogen Use Efficiency ◽  
Nitrogen Use ◽  
Below Ground ◽  
Use Efficiency

Plants are balanced systems that integrate processes of carbon fixation and uptake of water and nutrients to optimize resource acquisition. Response of Juniperusoccidentalis Hook. to reductions in above- and below-ground tissue was measured to determine effects on carbon dioxide assimilation, leaf conductance, intercellular carbon dioxide, xylem water potential, foliage nutrient concentration, aboveground growth, water-use efficiency, and potential photosynthetic nitrogen-use efficiencies. Approximately 50% of the old foliage was removed and lateral roots were severed at the canopy edge in early April 1988; physiological processes were measured during three periods in the summer of 1988. Foliage removal increased rates of carbon dioxide assimilation and photosynthetic nitrogen-use efficiency, but neither increased growth nor improved water status or nitrogen concentration of remaining foliage. Cutting lateral roots reduced assimilation, leaf conductance, foliage nitrogen concentration, branchlet elongation, water-use efficiency, and photosynthetic nitrogen-use efficiency. By late August, juvenile and small-adult J. occidentalis in the cut-top treatment had compensated for foliage removal by reestablishing patterns of water-use efficiencies similar to those of control plants, which may indicate that an overall metabolic control was functioning to regulate the balance between carbon dioxide assimilation and water loss. Cutting lateral roots had a more lasting effect on efficiencies; by late August, juveniles and small adults still had significantly lower water-use efficiencies than controls.

scholarly journals Cultivation of CNPA G3 sesame irrigated with saline water and fertilized with nitrate-N and ammonium-N

2017 ◽  
Vol 21 (1) ◽  
pp. 14-20 ◽  
Author(s):  
Geovani S. de Lima ◽  
Adaan S. Dias ◽  
Lauriane A. dos A. Soares ◽  
Hans R. Gheyi ◽  
José P. Camara Neto ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Water Use Efficiency ◽  
Water Use ◽  
Water Consumption ◽  
Saline Water ◽  
Early Maturation ◽  
Nitrate N ◽  
Ammonium N ◽  
Use Efficiency ◽  
Delayed Flowering

ABSTRACT The study aimed to evaluate the effects of irrigation with saline water and fertilization with nitrate (NO3--N) and ammonium (NH4+-N) ratios on growth, flowering, water consumption and water use efficiency of the sesame cv. CNPA G3. The treatments were distributed in randomized blocks in a 5 x 5 factorial with three replicates, referring to five levels of electrical conductivity of the irrigation water - ECw (0.6, 1.2, 1.8, 2.4 and 3.0 dS m-1) and nitrate (NO3--N) and ammonium (NH4+-N) (200/0, 150/50, 100/100, 50/150, 0/200 mg kg-1) ratios. Irrigation with saline water above 0.6 dS m-1 inhibited the growth, delayed flowering and promoted early maturation of capsules of sesame, cv. CNPA G3. The proportion of 0/200 mg kg-1 of NO3--N/NH4+-N promoted the greatest increase relative to stem diameter and height of sesame plants. Water consumption decreases with increasing ECw and was significantly lower in plants fertilized with the proportion of 0/200 of NO3--N/NH4+-N. The interaction between ECw levels and ammonium/nitrate proportions significantly affect water use efficiency, and the highest value was obtained with ECw of 0.6 dS m-1 and fertilization with 150:50 mg kg-1 of NO3--N and NH4+-N.

scholarly journals HEAVY CARBON AS A TRACER IN HETEROTROPHIC CARBON DIOXIDE ASSIMILATION

1941 ◽  
Vol 139 (1) ◽  
pp. 365-376 ◽  
Author(s):  
H.G. Wood ◽  
C.H. Werkman ◽  
Allan Hemingway ◽  
A.O. Nier
Keyword(s):  
Carbon Dioxide ◽  
Carbon Dioxide Assimilation ◽  
Heavy Carbon

scholarly journals Slow-release nitrogen fertilizers enhance growth, yield, NUE in wheat crop and reduce nitrogen losses under an arid environment

2021 ◽  
Author(s):  
Iqra Ghafoor ◽  
Muhammad Habib-ur-Rahman ◽  
Muqarrab Ali ◽  
Muhammad Afzal ◽  
Wazir Ahmed ◽  
...  
Keyword(s):  
Harvest Index ◽  
Nutrient Balance ◽  
Growth Yield ◽  
Wheat Crop ◽  
Negative Effects ◽  
Coated Urea ◽  
Use Efficiency ◽  
Partial Factor Productivity ◽  
Partial Factor ◽  
Coated Fertilizers

AbstractHigher demands of food led to higher nitrogen application to promote cropping intensification and produce more which may have negative effects on the environment and lead to pollution. While sustainable wheat production is under threat due to low soil fertility and organic matter due to nutrient degradation at high temperatures in the region. The current research explores the effects of different types of coated urea fertilizers and their rates on wheat crop under arid climatic conditions of Pakistan. Enhancing nitrogen use efficiency by using eco-friendly coated urea products could benefit growers and reduce environmental negative effects. A trial treatment included N rates (130, 117, 104, and 94 kg ha-1) and coated urea sources (neem coated, sulfur coated, bioactive sulfur coated) applied with equal quantity following split application method at sowing, 20 and 60 days after sowing (DAS). The research was arranged in a split-plot design with randomized complete block design had three replicates. Data revealed that bioactive sulfur coated urea with the application of 130 kg N ha-1 increased chlorophyll contents 55.0 (unit value), net leaf photosynthetic rate (12.51 μmol CO2 m-2 s-1), and leaf area index (5.67) significantly. Furthermore, research elucidates that bioactive sulfur urea with the same N increased partial factor productivity (43.85 Kg grain Kg-1 N supplied), nitrogen harvest index (NHI) 64.70%, and partial nutrient balance (1.41 Kg grain N content Kg-1 N supplied). The neem-coated and sulfur-coated fertilizers also showed better results than monotypic urea. The wheat growth and phenology significantly improved by using coated fertilizers. The crop reached maturity earlier with the application of bioactive sulfur-coated urea than others. Maximum total dry matter 14402 (kg ha-1) recorded with 130 kg N ha-1application. Higher 1000-grain weight (33.66 g), more number of grains per spike (53.67), grain yield (4457 kg ha-1), and harvest index (34.29%) were obtained with optimum N application 130 kg ha-1 (recommended). There is a significant correlation observed for growth, yield, and physiological parameters with N in the soil while nitrogen-related indices are also positively correlated. The major problem of groundwater contamination with nitrate leaching is also reduced by using coated fertilizers. Minimum nitrate concentration (7.37 and 8.77 kg ha-1) was observed with the application of bioactive sulfur-coated and sulfur-coated urea with lower N (94 kg ha-1), respectively. The bioactive sulfur-coated urea with the application of 130 kg N ha-1 showed maximum phosphorus 5.45 mg kg-1 and potassium 100.67 mg kg-1 in the soil. Maximum nitrogen uptake (88.20 kg ha-1) is showed by bioactive sulfur coated urea with 130 kg N ha-1 application. The total available NPK concentrations in soil showed a significant correlation with physiological attributes; grain yield; harvest index; and nitrogen use efficiency components, i.e., partial factor productivity, partial nutrient balance, and nitrogen harvest index. This research reveals that coating urea with secondary nutrients, neem oil, and microbes are highly effective techniques for enhancing fertilizer use efficiency and wheat production in calcareous soils and reduced N losses under arid environments.

Sign in / Sign up

Export Citation Format

Share Document