scholarly journals Symbiotic N2-Fixation Estimated by the15N Tracer Technique and Growth ofPueraria phaseoloides(Roxb.) Benth. Inoculated withBradyrhizobiumStrain in Field Conditions

Scientifica ◽  
2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Papa Saliou Sarr ◽  
Judith Wase Okon ◽  
Didier Aime Boyogueno Begoude ◽  
Shigeru Araki ◽  
Zachée Ambang ◽  
...  
Keyword(s):  
Ipomoea Batatas ◽  
Dry Matter ◽  
N Uptake ◽  
Dry Weight ◽  
Soil N ◽  
Tracer Technique ◽  
Pueraria Phaseoloides ◽  
Rhizobial Inoculation ◽  
Soil N Uptake ◽  
Eastern Cameroon

This field experiment was established in Eastern Cameroon to examine the effect of selected rhizobial inoculation on N2-fixation and growth ofPueraria phaseoloides. Treatments consisted of noninoculated andBradyrhizobium yuanmingenseS3-4-inoculatedPuerariawith three replications each.Ipomoea batatasas a non-N2-fixing reference was interspersed in eachPuerariaplot. All the twelve plots received 2 gN/m2of15N ammonium sulfate 10% atom excess. At harvest, dry matter yields and the nitrogen derived from atmospheric N2-fixation (%Ndfa) of inoculatedPuerariawere significantly (P<0.05) higher (81% and 10.83%, resp.) than those of noninoculatedPueraria. The inoculation enhanced nodule dry weight 2.44-fold. Consequently, the harvested N significantly (P<0.05) increased by 83% in inoculatedPueraria, resulting from the increase in N2-fixation and soil N uptake. A loss of 55 to 60% of the N fertilizer was reported, and 36 to 40% of it was immobilized in soil. Here, we demonstrated that both N2-fixing potential ofP. phaseoloidesand soil N uptake are improved through field inoculations using efficient bradyrhizobial species. In practice, the inoculation contributes to maximize N input in soils by the cover crop’s biomass and represent a good strategy to improve soil fertility for subsequent cultivation.

scholarly journals Substantial Leaf Shedding—A Consistent Phenomenon among High-yielding Sweetpotato Cultivars

HortScience ◽  
1993 ◽  
Vol 28 (8) ◽  
pp. 826-827 ◽  
Author(s):  
W.J. McLaurin ◽  
S.J. Kays
Keyword(s):  
Ipomoea Batatas ◽  
Dry Matter ◽  
Negative Impact ◽  
Dry Weight ◽  
Lower Percentage ◽  
Strong Positive Correlation ◽  
Storage Roots ◽  
Leaf Shedding ◽  
Total Dry Weight ◽  
Positive Correlations

Four high-yielding sweetpotato [Ipomoea batatas (L.) Lam.] cultivars displayed substantial leaf shedding, under typical field production conditions, that was not due to pathological or herbivory causes. Losses ranged from ≈ 45% to 60% of the total leaves formed by the normal harvest date during 2 years. There was a strong positive correlation between leaf shedding and the number of vines (r2 = 0.80) and nodes (r2 = 0.89) per plant. Likewise, positive correlations were found between leaf shedding and total dry weight (r2 = 0.67), root fresh weight (r2 = 0.65), root dry weight (r2 = 0.60), and vine dry weight (r2 = 0.68). Distinct differences were found among cultivars in dry-matter allocation within the plant. `Jewel' allocated a lower percentage of dry matter into vines and a higher percentage into storage roots. Estimated leaf dry matter losses due to leaf shedding ranged from 1.2 to 2.6 t·ha-1. High leaf losses appear to be closely related to vigorous vine growth and subsequent shading of older leaves but did not have a negative impact on storage root yield in the cultivars tested.

scholarly journals Regulation of Nitrogen Uptake at the Whole-plant Level: A Study in Almond Trees

1999 ◽  
Vol 9 (4) ◽  
pp. 598-600 ◽  
Author(s):  
Farbod Youssefi ◽  
Patrick H. Brown ◽  
Steve A. Weinbaum
Keyword(s):  
N Uptake ◽  
Prunus Dulcis ◽  
Inhibitory Effect ◽  
Tree Level ◽  
Soil N ◽  
Phloem Sap ◽  
Whole Plant ◽  
Soil N Uptake ◽  
Almond Trees ◽  
Plant Level

It has been proposed that a pool of amino N, whose size is determined by aboveground N demand, cycles in the plant and regulates soil N uptake by exerting an inhibitory effect at the root level. Several experiments were carried out to study this hypothesis in almond trees [Prunus dulcis (Mill.) D.A. Webb]. Based on the evidence found, there is an association, at the whole tree level, between sap N content and soil N uptake. The data are consistent with the possibility that increased phloem sap amino acids result in decreased uptake of soil N.

scholarly journals Evaluation of CROPGRO-Tomato Model under Different Dates of Planting and Cultivars under Semi-arid Environment

2021 ◽  
Vol 12 (5) ◽  
pp. 570-576
Author(s):  
L. Shravika ◽  
◽  
G. Sreenivas ◽  
A. Madhavi ◽  
A. Manohar Rao ◽  
...  
Keyword(s):  
Dry Matter ◽  
N Uptake ◽  
Dry Weight ◽  
Arid Environment ◽  
Field Investigation ◽  
Fruit Yield ◽  
Matter Production ◽  
Main Plot ◽  
Agriculture Research Institute ◽  
Semi Arid

A field investigation was undertaken during Kharif (June–September) 2019 at Agriculture Research Institute, Professor Jayashankar Telangana State Agriculture University, Rajendranagar, Hyderabad, Telengana State, India with an object to evaluate the CROPGRO-Tomato model under different dates of planting and cultivars.The experiment was carried out with dates of planting (02nd Jul, 12th Jul, 22nd Jul, 02nd Aug, 11th Aug, 23rd Aug, 03rd Sep and 13th Sep) as main plot treatments and cultivars US 440 and TO-3251 (Saaho) as sub-plot treatments. The CROPGRO-Tomato model performed well in the simulation of phenology, biomass, fruit yield and N uptake during calibration for US 440 and TO-3251.Calibration results revealed that the model perfectly predicted days to anthesis with no difference between simulated and observed data for both cultivars with RMSE of 0 days, the further model simulated the days to last picking,biomassat maturity, fruit yield and nitrogen uptake with RMSE of 0.9 and 0.7 day, 285 and 435 kg ha-1, 545 kg ha-1 and 389 kg ha-1 (dry weight), 6 and 5 kg ha-1 for US 440 and TO-3251 cultivars respectively. The calibrated model was used to further validate the experimental data and found that, simulation of days to anthesisand days to the last picking was excellent with NRMSE value of less than 10% for both cultivars,fair with dry matter production with NRMSE value of 25% for both cultivars and was poor with total fruit yield greater than 30% and N uptake for both cultivars under study was poor with NRMSE value more than 30%.

Winter wheat growth and nitrogen demand in south coastal British Columbia

1994 ◽  
Vol 74 (4) ◽  
pp. 443-451 ◽  
Author(s):  
A. A. Bomke ◽  
W. D. Temple ◽  
S. Yu
Keyword(s):  
British Columbia ◽  
Winter Wheat ◽  
Dry Matter ◽  
N Uptake ◽  
Growth Stages ◽  
Dry Matter Accumulation ◽  
Soil N ◽  
Low Input ◽  
Crop Development ◽  
Coastal British Columbia

Winter wheat, Triticum aestivum, is a new crop in south coastal British Columbia. The purposes of this study were to characterize plant development, dry matter accumulation and N uptake under low input and intensively managed systems as well as to assess the capability of some of the region’s soils to supply N to the crop. Grain yields, crop development and dry matter and N accumulation were similar to those reported from southern England. High amounts of winter rainfall (November–April precipitation ranged from 523 to 1111 mm) leach virtually all residual NO3 from south coastal B.C. soils and, without N fertilization, result in uniformly N deficient winter wheat. The low input N regime, 75 kg N ha−1 at Zadoks growth stage 31, plus soil N mineralized subsequent to the winter leaching period were sufficient in this study to maximize grain and total aboveground crop dry matter yields, but not to achieve adequate grain protein contents. The soils in the study were capable of supplying N in amounts sufficient to support only 30–53% of the maximum N uptake between growth stages 31 and 78. Appropriate quantities and timing of N are critical to successful production of high-yielding, good-quality wheat in south coastal British Columbia. Nitrogen management is likely to be most efficient when guided by the stage of crop development and demand and not by spring soil sampling and mineral N analysis. Key words: Winter wheat, N demand, soil N supply, crop development, intensive crop management, low input

Analysis of growth and tuber yield in sweet potato (Ipomoea batatas) cultivars

1977 ◽  
Vol 88 (2) ◽  
pp. 421-430 ◽  
Author(s):  
B. A. C. Enyi
Keyword(s):  
Sweet Potato ◽  
Ipomoea Batatas ◽  
Dry Matter ◽  
Tuber Yield ◽  
Dry Weight ◽  
Tuber Weight ◽  
Crop Growth Rate ◽  
Growing Seasons ◽  
Total Dry Weight ◽  
Bulking Rate

SUMMARYGrowth and tuber yield of local sweet potato cultivars were compared during the 1974 and 1975 growing seasons. Three cultivars significantly outyielded the others. The cultivar effect was associated with differences in individual tuber weight, rate of bulking and percentage of total dry matter diverted into the vine or stem. Mean crop growth rate (C) and percentage of total dry matter diverted into the tubers were greater in the higher yielding cultivars and there was positive and significant correlation between Cand final total dry weight. Leaf area duration (D) was greater in 1975 than in 1974 but the differences between cultivars in D was not consistent. Higher yielding cultivars had significantly greater tuber/leaf ratio than the other cultivars.Bulking rate and tuber weight were positively correlated with tuber yield, while the percentage of total dry matter diverted into the vine was negatively correlated with tuber yield.

DRY MATTER PRODUCTION AND NITROGEN ACCUMULATION IN NO-TILL WINTER WHEAT

1990 ◽  
Vol 70 (2) ◽  
pp. 461-472 ◽  
Author(s):  
B. A. DARROCH ◽  
D. B. FOWLER
Keyword(s):  
Winter Wheat ◽  
Nitrogen Fertilization ◽  
Dry Matter ◽  
N Uptake ◽  
Growing Season ◽  
Grain Protein ◽  
Soil N ◽  
N Yield ◽  
No Till ◽  
N Concentration

Norstar winter wheat (Triticum aestivum L.) was examined in 11 trials with the objective of determining the pattern of dry matter and nitrogen (N) accumulation in dryland stubbled-in winter wheat grown in Saskatchewan. In all 4 yr of this study, replicated no-till field trials were supplemented with 0, 34, 67 and 100 kg N ha−1 applied as ammonium nitrate (34-0-0) in early spring. A fifth treatment of 200 kg N ha−1 was evaluated in the final year of trials. Plant samples were collected at 2-wk intervals. Early season N uptake was more rapid than dry matter accumulation and 89% of the total N, compared to 70% of the total dry matter, was present at anthesis (Zadoks growth stages 60–68). Poor soil moisture availability limited N uptake after anthesis. Consequently, N uptake during the growing season was best described by a quadratic equation, Nitrogen yield = −29.1 + 3.02 Z − 0.018 Z2, where Z represents the Zadoks growth stage. Nitrogen concentrations of the stems and leaves decreased during the growing season while the N concentration of spikes varied among trials. Nitrogen fertilization often produced large increases in tissue N concentration at the beginning of the growing season. These differences decreased with time and by the end of the season tissue N concentrations were usually similar for all N rates. In general, when residual soil N levels were low to intermediate and rainfall was adequate, N fertilization increased dry matter yield, plant N yield, grain yield and grain protein yield. Nitrogen fertilization increased plant N concentration, plant N yield, grain protein concentration and grain protein yield when soil N reserves were intermediate to high and rainfall was adequate.Key words: Nitrogen uptake, wheat (winter), nitrogen response, tissue nitrogen, grain protein, environment

scholarly journals Inhibition of N2 Fixation by N Fertilization of Common Bean (Phaseolus vulgaris L.) Plants Grown on Fields of Farmers in the Eastern Cape of South Africa, Measured Using 15N Natural Abundance and Tissue Ureide Analysis

2021 ◽  
Vol 3 ◽  
Author(s):  
Simon J. Habinshuti ◽  
Sipho T. Maseko ◽  
Felix D. Dakora
Keyword(s):  
South Africa ◽  
Single Dose ◽  
Phaseolus Vulgaris ◽  
N Uptake ◽  
N Fertilizer ◽  
Double Dose ◽  
Soil N ◽  
Eastern Cape ◽  
Bean Plants ◽  
Soil N Uptake

Inhibition of N2 fixation in N-fertilized common bean (Phaseolus vulgaris L.) plants growing on the fields of farmers in the Eastern Cape of South Africa was measured using 15N natural abundance and tissue ureide analysis. The N-fertilized bean plants revealed greater soil N uptake, higher concentrations of nitrate in organs, low tissue ureide levels, and much lower percent relative ureide-N abundance when compared with unfertilized plants. In contrast, the unfertilized plants showed greater nodule fresh weight, higher N derived from fixation (e.g., 84.6, 90.4, and 97.1% at Lujecweni fields 2, 3, and 4, respectively), increased amount of N-fixed (e.g., 163.3, 161.3, and 140.3 kg ha−1 at Lujecweni fields 2, 3, and 4, respectively), greater ureide concentration in stems and petioles, higher % relative ureide-N abundance, and low soil N uptake. We also found that the percent N derived from fixation (%Ndfa) was very high for some bean plants receiving a double dose of N fertilizer [e.g., Lujecweni field 1 (51.8%) and Tikitiki field 1 (53.3%], and quite high for others receiving a single dose of N fertilizer [e.g., Tikitiki field 2 (50.1%), Mfabantu fields 1 and 2 (45.5 and 79.9%, respectively), and St. Luthberts field 1 (58.9%)]. Though not assessed in this study, it is likely that the rhizobia that effectively nodulated the N-fertilized bean plants and fixed considerable amounts of symbiotic N had constitutive and/or inducible nitrate reductase genes for reducing nitrate in nodules and bacteroids, hence their ability to form root nodules and derived high %Ndfa in bean with added N. While single- and double-dose N fertilizer applications increased plant growth and grain yield compared to unfertilized bean plants, the single-dose N fertilizer application produced much greater grain yield than the double dose. This indicates that farmers should stop using a double dose of N fertilizers on bean production, as it decreases yields and can potentially pollute the environment. This study has however shown that government supply of free N fertilizers to resource-poor farmers in South Africa increased bean yields for food/nutritional security.

scholarly journals Contribution of previous year’s leaf N and soil N uptake to current year’s leaf growth in sessile oak

2016 ◽  
Author(s):  
Stephane Bazot ◽  
Chantal Fresneau ◽  
Claire Damesin ◽  
Laure Barthes
Keyword(s):  
Leaf Growth ◽  
N Uptake ◽  
Soil N ◽  
Rhizospheric Soil ◽  
Growing Seasons ◽  
Soil N Uptake ◽  
Previous Autumn ◽  
Leaf N ◽  
N Pool

Abstract. The origin of the N which contributes to the synthesis of N reserves of in situ forest trees in autumn, and to the growth of new organs the following spring, is currently poorly documented. To characterize the metabolism of various possible N sources (plant N and soil N), six distinct 20 year-old sessile oaks were 15N labelled by spraying 15NH415NO3: (i) on leaves in May, to label the N pool remobilized in the autumn for synthesis of reserves; (ii) on soil in the autumn, to label the N pool taken up from soil; (iii) on soil at the beginning of the following spring, to label the N pool taken up from soil in the spring. The partitioning of 15N in leaves, twigs, phloem, xylem, fine roots, rhizospheric soil and microbial biomass was followed during two growing seasons. Results showed a significant incorporation of 15N in the soil-tree system; more than 30 % of the administered 15N was recovered. Analysis of the partitioning clearly revealed that in autumn, roots’ N reserves were formed from foliage 15N (73 %) and to a lesser extent from soil 15N (27 %). The following spring, 15N used for the synthesis of new leaves came first from 15N stored during the previous autumn, mainly from 15N reserves formed from foliage (95 %). Thereafter, when leaves were fully expanded, 15N uptake from soil during the previous autumn and before budburst contributed to the formation of new leaves (60 %).

scholarly journals 614 Nitrogen Uptake Efficiency of Apple Rootstocks and Scions

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 553C-553
Author(s):  
Paula B. Aguirre ◽  
Teryl R. Roper ◽  
Armand R. Krueger
Keyword(s):  
Ammonium Nitrate ◽  
Nitrogen Uptake ◽  
N Uptake ◽  
Soil N ◽  
Apple Rootstocks ◽  
Total N ◽  
Wood Tissue ◽  
Nitrogen Uptake Efficiency ◽  
Uptake Efficiency ◽  
Soil N Uptake

The uptake efficiency of apple scions and rootstocks has not been studied in the field. Using 15N (ammonium nitrate, 1 atom % 15N) we compared nitrogen uptake efficiency of 12 rootstocks grafted to one scion (Gala) and of 20 scions on the same clonal rootstock (M.9 EMLA) in orchards located in northeastern Wisconsin. Trees were treated in either Fall or Spring 1998 with 40 g actual N per tree applied as a liquid to the soil. N uptake was assessed by measuring 15N in leaf and wood tissue taken monthly from June to Oct. 1998. Tissues were oven-dried and analized using a ratio mass spectrometer. Treatment differences were greater among scions with the same rootstocks than among rootstocks with the same scion. Total N and 15N content differences were found between roostocks and these values were inversely related to tree size.

Sign in / Sign up

Export Citation Format

Share Document