scholarly journals Dry matter and nitrogen accumulation and use in spring barley

2011 ◽  
Vol 49 (No. 1) ◽  
pp. 36-47 ◽  
Author(s):  
N. Przulj ◽  
V. Momčilović

During growth, kernel of cereals can be provided with carbohydrate and nitrogen (N) from the translocation of pre-anthesis accumulated reserves stored either in the vegetative plant parts or from current assimilation during kernel development. This study was conducted to assess the effects of nitrogen level and cultivars on dry matter and N accumulation and mobilization during pre-anthesis and post-anthesis. Twenty two-rowed spring barley (Hordeum vulgare L.) cultivars were grown on a non-calcareous chernozem soil in four growing seasons (1995–1998) atNovi Sad (45°20'N, 15°51'E,86 m a.s.l.) at two nitrogen levels. Dry matter accumulation before anthesis ranged from less than 50% in unfavorable to 90% in favorable growing conditions. Dry matter translocation occurred in favorable growing conditions only. Pre-anthesis accumulated N represented 57–92% and 54–129% of total N at maturity at the low and high N levels, respectively. Translocated N represented 41–85% and 37–153% of grain N at the low and high N level, respectively. N losses occurred in favorable growing conditions when anthesis N exceeded 150 kg/ha. N accumulation during grain filling was in negative correlation with dry matter and N accumulation before anthesis. The N harvest index was 0.57–0.63 and 0.71–0.74 in unfavorable and favorable growing conditions, respectively. Selection of genotypes with a higher ability of pre-anthesis reserve utilization or genotypes with longer leaf area duration after anthesis may be two possible solutions in spring barley breeding for Mediterranean growing conditions.

1981 ◽  
Vol 96 (1) ◽  
pp. 167-186 ◽  
Author(s):  
D. W. Lawlor ◽  
W. Day ◽  
A. E. Johnston ◽  
B. J. Legg ◽  
K. J. Parkinson

SUMMARYThe effects of water deficit on growth of spring barley were analysed under five irrigation treatments. One crop was irrigated at weekly intervals from emergence throughout the growing season, and one was not irrigated at all after emergence. Soil water deficits in the other treatments were allowed to develop early, intermediate or late in the crop's development.Weekly irrigation produced a crop with a large leaf area index (maximum value 4) and maintained green leaf and awns throughout the grain-filling period. Early drought decreased leaf area index (maximum value 2) by slowing expansion of main-stem leaves and decreasing the number and growth of tiller leaves. Leaf senescence was also increased with drought. Drought late in the development of ears and leaves and during the grain-filling period caused leaves and awns to senesce so that the total photosynthetic areas decreased faster than with irrigation. Photosynthetic rate per unit leaf area was little affected by drought so total dry-matter production was most affected by differences in leaf area.Early drought gave fewer tillers (550/m2) and fewer grains per ear (18) than did irrigation (760 tillers/m2 and 21 grains per ear). Late irrigation after drought increased the number of grains per ear slightly but not the number of ears/m2. Thus at the start of the grain-filling period crops which had suffered drought early had fewer grains than irrigated (9·5 and 18·8 × 103/m2 respectively) or crops which suffered drought later in development (14 × 103/m2).During the first 2 weeks of filling, grains grew at almost the same rate in all treatments. Current assimilate supply was probably insufficient to provide this growth in crops which had suffered drought, and stem reserves were mobilized, as shown by the decrease in stem mass during the period. Grains filled for 8 days longer with irrigation and were heavier (36–38 mg) than without irrigation (29–30 mg). Drought throughout the grainfilling period after irrigation earlier in the season resulted in the smallest grains (29 mg).Grain yield depended on the number of ears, the number of grains per ear and mass per grain. Early drought decreased tillering and tiller ear production and the number of grains that filled in each ear. Late drought affected grain size via the effects on photosynthetic surface area.Drought decreased the concentrations of phosphorus, potassium and magnesium in the dry matter of crops, and irrigation after drought increased them. Concentration of nitrogen was little affected by treatment. Possible mechanisms by which water deficits and nutrient supply affect crop growth and yield are discussed.


1995 ◽  
Vol 43 (4) ◽  
pp. 419-433
Author(s):  
H. Biemond ◽  
J. Vos ◽  
P.C. Struik

Three greenhouse trials and one field trial were carried out on Brussels sprout cv. Icarus SG2004 in which the treatments consisted of different N amounts and application dates. DM and N accumulation in stems, apical buds and groups of leaf blades, petioles and sprouts were measured frequently throughout crop growth. Total amounts of accumulated DM and N were affected by amount of N applied and date of application, but the final harvest indexes for DM and N (0.10-0.35 and 0.20-0.55, respectively) were not significantly affected by treatments in most experiments. Nitrate N concentrations were only high (up to about 2%) shortly after planting. The total N concentration of leaf blades and petioles increased with increasing leaf number. This increase resulted from a decreasing N concentration during the leaf's life. The total N concentration in sprouts changed little with leaf number.


1983 ◽  
Vol 29 (8) ◽  
pp. 924-929 ◽  
Author(s):  
Vera L. D. Baldani ◽  
José Ivo Baldani ◽  
Johanna Döbereiner

In two field experiments, wheat was inoculated with various strains of Azospirillum spp. The two A. brasilense nir− strains isolated from surface-sterilized wheat roots increased the number of Azospirillum in surface-sterilized roots, plant dry matter, and percent N. The total N accumulated in plant tops at heading stage was increased by 30% in the first experiment (strain Sp 107 st) and by 51 and 89% (strains Sp 107 st and Sp 245, respectively) in the second experiment. The Azospirillum numbers (MPN) in chloramine-t treated roots were correlated with total nitrogen accumulation in plant tops (r = 0.92**). Numbers of Azospirillum in nonsterilized roots did not correlate with total plant N accumulation.


1994 ◽  
Vol 122 (3) ◽  
pp. 385-391 ◽  
Author(s):  
K. F. Ng Kee Kwong ◽  
J. Deville

SUMMARYThe patterns of N uptake and dry matter synthesis by sugarcane (Saccharum hybrid spp.) were studied at four locations in Mauritius with 15N–labelled ammonium sulphate (100 kg N/ha) applied either in a single dressing in September or in two split applications in September and the following February. More than 80% of the total N recovered at harvest (100–120 kgN/ha) was absorbed by the sugarcane during an active uptake period from October to January. Split application prolonged this active N uptake until April only and had no effect on dry matter accumulation. While total Nabsorbed by above-ground sugarcane showed no decline over time, 10–20 kg N/ha of the 15N–labelled N was lost from the green tops even when the N was applied on two occasions. The fertilizer N losses from above-ground sugarcane were, however, not evident when fertilizer N recovery with time was studied by the difference method. In view of the observed losses of fertilizer N from the aerial parts of sugarcane, measurement of fertilizer N recovery at harvest by the N isotope dilution technique underestimates fertilizer N uptake by sugarcane and attributes too large a fraction of N loss to denitrification/volatilization of NH3.


Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2310
Author(s):  
Yang Yang ◽  
Wenxin Zha ◽  
Kailei Tang ◽  
Gang Deng ◽  
Guanghui Du ◽  
...  

Hemp is a multipurpose crop that is cultivated worldwide for fiber, oil, and cannabinoids. Nitrogen (N) is a key factor for getting a higher production of hemp, but its application is often excessive and results in considerable losses in the soil–plant–water continuum. Therefore, a rational N supply is important for increasing N efficiency and crop productivity. The main objective of this paper was to determine the responses of four hemp cultivars to different levels of exogenous-N supply as nutrient solution during the vegetative growing period. The experiment was conducted at Yunnan University in Kunming, China. Yunma 1, Yunma 7, Bamahuoma, and Wanma 1 were used as the experimental materials, and five N supplying levels (1.5, 3.0, 6.0, 12.0, and 24.0 mmol/L NO3-N in the nutrient solution) were set by using pot culture and adding nutrient solution. The root, stem, and leaf of the plant were sampled for the determination of growth indexes, dry matter and N accumulation and distribution, and physiological indicators. The plant height, stem diameter, plant dry weight, and plant N accumulation of four hemp cultivars were significantly increased with the increase in exogenous-N supply. Root/shoot dry weight ratios, stem mass density, and N use efficiency decreased significantly with the increase in exogenous-N supply. Nitrogen accumulation, chlorophyll content, soluble protein content, and nitrate reductase activity in leaves were increased with the increase in exogenous-N supply. Among the four indexes, the increase in N accumulation was more than the increase in NR activity. The activities of superoxide dismutase and peroxidase in leaves were increased first and then decreased with the increase in exogenous-N supply, with the maximum value at N 6.0 mmol/L, while the content of malondialdehyde in leaves increased significantly when the level of exogenous-N supply exceeded 6.0 mmol/L. These results revealed that increasing the exogenous-N supply could improve the plant growth, dry matter accumulation, and N accumulation in hemp during the vegetative growth period, but N supply should not exceed 6.0 mmol/L. Among four hemp cultivars, Wanma 1 performed well at 6.0 mmol/L N application.


2011 ◽  
Vol 39 (2) ◽  
pp. 196 ◽  
Author(s):  
Nurdilek GULMEZOGLU ◽  
Nihal KAYAN

This research aimed to determine the effect of different levels of nitrogen (N) on the growth, yield and the N accumulation of lentil plants grown under rain-fed conditions. The two-year field experiments with lentil were arranged in a randomised complete block design. Nitrogen was applied at four rates (0, 20, 40 and 60 kg ha-1) and all of the plots received half of the N rates before sowing in October and the remaining N rate in spring. The plants were harvested in the following stages: the first multifoliate leaf unfolding at the fifth node (V5) full seed or seed on nodes 10-13 that fill pod cavities (R6) and maturity (R8). The dry weight and N concentration of the shoot (leaf+stem), pod wall, and seed were then measured. It has been found that N application significantly affected the lentil characteristics. The maximum biomass accumulation and N accumulation were obtained at R6, and the N fertiliser had a positive effect on the seed weight and N accumulation. It can be suggest that 20 kg N ha-1 will increase the per-plant dry matter and N accumulation of the seeds under rain-fed conditions.


2004 ◽  
Vol 142 (6) ◽  
pp. 639-657 ◽  
Author(s):  
D. R. KINDRED ◽  
M. J. GOODING

Four field experiments over 2 years investigated whether wheat hybrids had higher nitrogen-use efficiency (NUE) than their parents over a range of seed rates and different N regimes. There was little heterosis for total N in the above-ground biomass (NYt), but there was high-parent heterosis for grain N yields (NYg) in two of the hybrids, Hyno Esta and Hyno Rista, associated with greater nitrogen harvest index (NHI). Overall, the hybrids did not significantly increase the total dry matter produced per unit N in the above-ground crop (NUtEt), but did increase the grain dry matter per unit N in the above ground crop (NUtEg). The improvement in NUtEg was at the partial detriment of grain N concentration. Heterosis for grain NYg in Hyno Esta was lower at zero-N, suggesting that it did not achieve higher yields through more efficient capture or utilization of N. The greater NHI in Hyno Esta appeared to be facilitated by both greater N uptake, and remobilization of N from vegetative tissues, after anthesis.The response of N efficiency and uptake to seed rate was dependent on N supply and season. Where N fertilizer was applied, N uptake over time was slower at the lower seed rates, but where N was withheld N capture at the lowest seed rate soon approached the N capture of the higher seed rates. During grain filling, the rate of accumulation of N into the grain increased with seed rate and the duration of N accumulation decreased with seed rate. With N applied, N yields increased to an asymptote with seed rate, when N was withheld there was little response of N yields to seed rate. In 2002, N utilization efficiency (NUtEt and NUtEg) also increased asymptotically with seed rate, but in 2003 seed rate had little effect on N utilization efficiency. When nitrogen fertilizer had not been applied, NHI consistently decreased with increasing seed rate. The timing of N application made little difference to NUE, NY, or NUtE.


1992 ◽  
Vol 72 (4) ◽  
pp. 1067-1074 ◽  
Author(s):  
B. L. Vasilas ◽  
R. L. Nelson

A positive relationship generally exists between the duration of seed-fill period (SFP) and seed yield in soybean, but exceptions have been reported. The objective of this research was to determine if differences in N2 fixation or N accumulation could explain inconsistent relationships between duration of SFP and seed yield in soybean. For this study, five experimental soybean (Glycine max L. [Men.]) lines were selected on the bases of differences in SFP and seed yield in previous experiments. The experiment was designed to compare lines differing in both SFP and seed yield, differing in SFP but not seed yield, and differing in seed yield but not SFP. Total N2 fixation, using 15N-dilution techniques; total N accumulation, using a semi-micro-Kjeldahl procedure; and total dry matter accumulation, including all vegetative material abscised before maturity were measured on these lines grown in a Flanagan silt loam (fine, montmorillonitic, mesic Aquic Argiudolls) in 1984 and 1985 at Urbana, IL. Mean dinitrogen fixed ranged from 36 to 76 kg ha−1 in 1984 and from 65 to 113 kg ha−1 in 1985. The percentage of the total plant N derived from fixation ranged from 17 to 35% in 1984 and from 32 to 48% in 1985. Statistically significant differences in seed yield were not detected in this experiment because of the high coefficient of variation associated with the small plot size. High N2 fixation was not related to duration of SFP or previous seed yield classification. Total plant N did not differ among these genotypes. For these soybean lines differences in duration of SFP and previous seed yield classification were not related to total N2 fixation or N accumulation.Key words: Glycine max, harvest index, N partitioning, N2 fixation, seed-fill period


Plants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1222
Author(s):  
Lía Olmedo Pico ◽  
Tony Vyn

Progressive N assimilation by maize kernels may constrain dry matter (DM) accumulation and final kernel weights (KW). We sought to better understand whole-plant and kernel N mechanisms associated with incremental DM and N accumulation patterns in kernels during grain fill. Maize was grown with multiple fertilizer N rates and N timings or plant densities to achieve a wide N availability gradient. Whole-plant DM and N sampling enabled determination of apparent N nutrition sufficiency at flowering (NNIR1) and when linear-fill began (NNIR3). Linear-plateau, mixed-effects models were fitted to kernel DM and N accumulation data collected weekly from early R3. Higher N supply, regardless of application timing or plant density, increased grain-fill duration (GFD) and, more inconsistently, effective grain-filling rate (EGFR). Kernels accumulated DM and N for similar durations. Both final KW and kernel N content increased consistently with N availability mostly because of higher kernel N accumulation rates (KNAR) and duration (KNAD). Both NNIR1 and NNIR3 were positively associated with KNAD and KNAR, and less strongly with EGFR. These results confirm the direct role of kernel N accumulation, in addition to prior NNI, in limiting KW gain rates and duration during grain filling.


2012 ◽  
Vol 32 (5) ◽  
pp. 831-839 ◽  
Author(s):  
Rilner A. Flores ◽  
Segundo Urquiaga ◽  
Bruno J. R. Alves ◽  
Leonardo S. Collier ◽  
Robert M. Boddey

The objective of this study was to evaluate the performance of two genotypes of elephant grass, fertilized with and without N, for biomass production for energy use under the edaphoclimatic conditions of the Cerrado. The genotypes Roxo and Paraíso, grown in a field experiment in a Latosol in the Cerrado region were evaluated for biomass yield, nitrogen accumulation, C:N and stem:leaf ratios, fibre, ash and P and K contents and calorific value. The accumulated dry biomass ranged from 30 to 42 Mg ha-1 and showed no response to nitrogen fertilization with the lowest biomass obtained by the genotype Paraíso and the highest by Roxo. The total N accumulation followed the same pattern as for dry matter, ranging from 347 to 539 kg N ha-1. C:N and stem:leaf ratio of the biomass produced did not vary with treatments. The fibre contents were higher in genotype Paraíso and the highest levels of ash in the genotype Roxo. The K content in the biomass was higher in genotype Roxo and P did not vary between genotypes. The calorific value averaged 18 MJ kg-1 of dry matter and did not vary with the levels of N in leaves and stems of the plant. Both genotypes, independent of N fertilization, produced over 30 Mg ha-1 of biomass under Cerrado conditions.


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