Seasonal fluctuations in the nitrogen content of the sultana vine

1957 ◽  
Vol 8 (2) ◽  
pp. 162 ◽  
Author(s):  
D McEAlexander

Estimates were made of dry matter and nitrogen contents of parts of sultana vines sampled a t frequent intervals from October to January in one season and January to July in the following season. From early October until the commencement of leaf drop in February there was a linear increase in the amount of nitrogen in the annual aerial growth. This nitrogen was present mainly in the laminae and fruit. After February the amount of nitrogen in the fruit continued to increase while that in the leaves decreased. The loss from the leaves could be partly accounted for by translocation to fruit or woody tissues and the remainder by leaf fall. The data obtained gave no indication of the best time for applying nitrogen to sultana vines. The amount of nitrogen in stems, and also the percentage of nitrogen in trunks, main roots, and feeder roots, increased to July, which suggested that root absorption from the soil continued throughout autumn. It is suggested that the total nitrogen content of laminae gives the most reliable indication of seasonal nitrogen uptake provided that due allowance is made for time of sampling. '

1972 ◽  
Vol 12 (55) ◽  
pp. 126 ◽  
Author(s):  
DA Little

Twelve feeds were given to oesophageally-fistulated cattle, and the chemical composition of each was compared with that of bolus material extruded while eating them. The nitrogen contents of the feeds ranged from 0.55 to 3.19 per cent on a dry matter basis. Feeds and complete boluses were dried and analysed for nitrogen, phosphorus, ash and neutral-detergent-soluble material (NDSM). Both nitrogen and NDSM in ingested feed could be reliably estimated by analysis of extruded bolus material ; the relation between feed and bolus nitrogen was slightly more precise when expressed on an organic matter basis, whereas that for material soluble in neutral detergent was closer on a dry matter basis. The phosphorus and ash contents of feeds were substantially and variably elevated by saliva and could not be estimated from analysis of the bolus. The nitrogen content of saliva secreted during rest was found to be significantly affected by dietary nitrogen concentration, but that of saliva secreted during chewing was not ; it is suggested that this explains the relative absence of an effect of salivary contamination on bolus nitrogen.


1961 ◽  
Vol 41 (3) ◽  
pp. 469-478 ◽  
Author(s):  
A. J. McGinnis ◽  
R. Kasting

The dry matter content of the internodes of the wheat varieties, Thatcher, Rescue, and Golden Ball, grown on non-irrigated land varied with age, variety, and internode. The nitrogen content of the stem tissues varied from 6 per cent for immature to less than 1 per cent for mature tissues. The nodes of these wheat plants generally contained less dry matter and more nitrogen than did the internodes. At maturity the top third of each of the two uppermost internodes of Thatcher grown on irrigated land contained the highest percentages of dry matter and nitrogen, and the bottom third contained the lowest. The stems of the wheats and of Eagle oats were not greatly different in dry matter and nitrogen content during the period when larvae of the wheat stem sawfly, Cephus cinctus Nort., usually die in oat plants.Resistance of solid-stemmed wheats to the sawfly does not appear to be associated with a quantitative nutritional deficiency of either moisture or nitrogen. The analyses are consistent with the hypothesis that older larvae in solid-stemmed wheats die as a result of desiccation. Pith of Golden Ball contained more moisture than did that of Rescue, which supports the view that greater egg mortality may occur in the former variety because of the higher moisture content.


1961 ◽  
Vol 41 (1) ◽  
pp. 176-187 ◽  
Author(s):  
E. A. Grant ◽  
C. S. Brown

Over 2 tons of dry matter per acre were obtained from pure seedings of timothy and of brome in the seeding year with an application of 100 pounds of nitrogen per acre. Nitrogen at 200 and 400 pounds per acre produced no further significant yield increase. In the second year, yields were significantly increased by each increment of nitrogen applied in the seeding year up to and including 400 pounds per acre with brome and 200 pounds per acre with timothy. Nitrogen content of grasses increased with each increment of nitrogen in the seeding year but this effect was not consistent in the second year. Over the 2-year period grasses recovered approximately 65 per cent of the applied nitrogen at the 100- and 200-pound levels and about 40 per cent at the 400-pound level.Red clover and alfalfa seeded in mixture with timothy and with brome were about equal in yield to grass alone plus 100 pounds of nitrogen in the seeding year and were much superior in the second year. Application of 100 pounds of nitrogen to grass-legume mixtures increased both yield and nitrogen content in the first cutting. In subsequent cuttings, total yield and legume fraction of the yield were often depressed by nitrogen treatment; exceptions were noted where legume stands were weak.Apparent nitrogen fixation by the legumes was consistently reduced by nitrogen treatment. Vigorous legume stands had an apparent nitrogen fixation of 60 pounds per acre in the seeding year and up to 200 pounds in the second year.


1968 ◽  
Vol 8 (32) ◽  
pp. 270 ◽  
Author(s):  
DJ Minson ◽  
R Milford

Pangola (Digitaria decumbens), kikuyu (Pennisetum clandestinum), setaria (Setaria sphacelata), and buffel grasses (Cenchrus ciliaris) were cut at different stages of growth and artificially dried to provide ten feeds with a range of leaf percentages (13-56), nitrogen contents (0.42-3.70 per cent), and acid detergent fibre percentage (26.3-43.3). Half of each cut was chaffed and the remainder pelleted. Both pellets and chaff were fed to Merino wethers in metabolism cages. Pelleting decreased the mean digestibility of dry matter by 6.8 percentage units, nitrogen by 2.2 percentage units, and ADF by 11.5 percentage units. Pelleting increased the mean voluntary intake by sheep 47 per cent for dry matter and 27 per cent for digestible dry matter with only minor differences in response to pelleting mature and young grass. The smallest increase from pelleting was 4.1 per cent for buffel grass containing 0.42 per cent N. In grass of the same age in which the nitrogen content had been increased to 0.75 by fertilizer nitrogen, pelleting increased intake by 26.6 per cent. It was concluded that with mature tropical grasses the response to pelleting may be limited by a low nitrogen content. Pelleting may be a useful technique for eliminating the effect of physical structure when studying factors affecting the voluntary intake of pasture plants.


1985 ◽  
Vol 21 (2) ◽  
pp. 175-182 ◽  
Author(s):  
S. P. Wani ◽  
S. Chandrapalaiah ◽  
P. J. Dart

SUMMARYThe results of field experiments conducted with millet cultivars inoculated with different nitrogen-fixing bacteria at the ICRISAT Centre, Hyderabad, India are described. Significant interactions were observed between host cultivars and bacterial strains, but some cultivars showed consistently increased grain and dry matter yields, suggesting the possibility of exploiting suitable plant and nitrogen-fixing bacterial associations for increasing grain yield. Inoculation also resulted in increased nitrogen uptake up to 14.9 kg ha−1, and larger grain nitrogen contents.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiaodan Wang ◽  
Yaliang Wang ◽  
Yuping Zhang ◽  
Jing Xiang ◽  
Yikai Zhang ◽  
...  

AbstractDetermination of the optimal fertilization method is crucial to maximize nitrogen use efficiency and yield of different rice cultivars. Side-deep fertilization with controlled-release nitrogen, in conjunction with machine transplanting and subsequent topdressing, was applied to Indica–japonica hybrid rice ‘Yongyou1540’ (YY1540) and indica hybrid rice ‘Tianyouhuazhan’ (TYHZ). Four nitrogen treatments were applied in 2018 and 2019: traditional nitrogen application with quick-release nitrogen (T1), single-dose deep fertilization at transplanting with 100% controlled-release nitrogen (T2), and deep fertilization of 70% controlled-release nitrogen and topdressing of 30% quick nitrogen at tillering (T3), or at panicle initiation (T4). Side-deep fertilization reduced the fertilizer application frequency without causing yield loss, T4 enhanced the yield of YY1540 by increasing the number of productive tillers and number of spikelets per panicle compared with T1, T2 and T3. The yield of TYHZ showed no significant difference among treatments. The T4 treatment decreased the number of tillers at the tilling peak stage and increased the percentage productive tillers and number of differentiated spikelets. Compared with the other treatments, T4 increased dry matter accumulation and leaf area index during panicle initiation and grain ripening, and contributed to enhanced nitrogen uptake and nitrogen utilization in YY1540. On average, nitrogen uptake and utilization in YY1540 were highest in T4, but no significant differences among treatments were observed in TYHZ. Dry matter accumulation and nitrogen uptake from panicle initiation to heading of YY1540 were correlated with number of spikelets per panicle, but no significant correlations were observed for TYHZ. Supplementary topdressing with quick-release nitrogen at the panicle initiation stage was required to increase yield of indica–japonica hybrid rice, whereas single-dose deep fertilization with controlled-release nitrogen is satisfactory for the indica hybrid cultivar.


2021 ◽  
Vol 3 (1) ◽  
pp. 29-49
Author(s):  
Ghizlane Astaoui ◽  
Jamal Eddine Dadaiss ◽  
Imane Sebari ◽  
Samir Benmansour ◽  
Ettarid Mohamed

Our work aims to monitor wheat crop using a variety-based approach by taking into consideration four different phenological stages of wheat crop development. In addition to highlighting the contribution of Red-Edge vegetation indices in mapping wheat dry matter and nitrogen content dynamics, as well as using Random Forest regressor in the estimation of wheat yield, dry matter and nitrogen uptake relying on UAV (Unmanned Aerial Vehicle) multispectral imagery. The study was conducted on an experimental platform with 12 wheat varieties located in Sidi Slimane (Morocco). Several flight missions were conducted using eBee UAV with MultiSpec4C camera according to phenological growth stages of wheat. The proposed methodology is subdivided into two approaches, the first aims to find the most suitable vegetation index for wheat’s biophysical parameters estimation and the second to establish a global model regardless of the varieties to estimate the biophysical parameters of wheat: Dry matter and nitrogen uptake. The two approaches were conducted according to six main steps: (1) UAV flight missions and in-situ data acquisition during four phenological stages of wheat development, (2) Processing of UAV multispectral images which enabled us to elaborate the vegetation indices maps (RTVI, MTVI2, NDVI, NDRE, GNDVI, GNDRE, SR-RE et SR-NIR), (3) Automatic extraction of plots by Object-based image analysis approach and creating a spatial database combining the spectral information and wheat’s biophysical parameters, (4) Monitoring wheat growth by generating dry biomass and wheat’s nitrogen uptake model using exponential, polynomial and linear regression for each variety this step resumes the varietal approach, (5) Engendering a global model employing both linear regression and Random Forest technique, (6) Wheat yield estimation. The proposed method has allowed to predict from 1 up to 21% difference between actual and estimated yield when using both RTVI index and Random Forest technique as well as mapping wheat’s dry biomass and nitrogen uptake along with the nitrogen nutrition index (NNI) and therefore facilitate a careful monitoring of the health and the growth of wheat crop. Nevertheless, some wheat varieties have shown a significant difference in yield between 2.6 and 3.3 t/ha.


1985 ◽  
Vol 65 (4) ◽  
pp. 897-903 ◽  
Author(s):  
D. M. VEIRA ◽  
M. IVAN ◽  
G. BUTLER ◽  
J. G. PROULX

Following weaning at 6–7 mo of age, 36 beef steers were used to determine production responses when grass silage was supplemented with barley or fishmeal. The silage was made from direct-cut, formic- acid-treated grass harvested from a mixed sward and had a high nitrogen content but poor fermentation characteristics. The silage was fed ad libitum for 98 days either alone or supplemented with 500 g fishmeal or 500 g barley per day. Both fishmeal and barley increased total dry matter intake (P < 0.01) by an amount equivalent to the quantity of supplement offered but had no effect on silage intake (P > 0.05). Steers fed the fishmeal grew substantially faster than either the barley (0.53 kg/day) or unsupplemented (0.54 kg/day) groups (P < 0.01). Fishmeal supplementation resulted in a large reduction (35%) in the amount of feed required per kilogram of gain. Key words: Cattle, grass silage, fishmeal, growth


1972 ◽  
Vol 52 (4) ◽  
pp. 681-687 ◽  
Author(s):  
R. J. BOILA ◽  
T. J. DEVLIN

Four dairy steers were allotted to four lysine infusion levels in a 4 × 4 latin square design and fed an 11.5% crude protein (90% dry matter (DM)) diet continuously (10-min intervals every 24 hr). Lysine hydrochloride equivalent to 0.0, 3.0, 6.0, and 9.0 g lysine per day was infused per abomasum. When 9 g lysine were infused per day, the percent of absorbed nitrogen (N) retained was significantly (P < 0.05) reduced; urinary N excretion as a percentage of N intake and plasma-free lysine were increased significantly compared with the other three infusion treatments. The infusion of 9 g lysine per day apparently exceeded the body tissue requirements for this amino acid and the excess N was excreted in the urine. A possibility of lysine being limiting (0.28% lysine of a 100% DM diet) was apparently offset by the synthesis of lysine by rumen microorganisms, which increased the dietary lysine two- to threefold. Increased levels of infused lysine did not result in a linear increase of lysine in the abomasum. With 3 g per day lysine infusion rumen ammonia and N retentions were high. However, a smaller amount of N reached the abomasum with steers on this treatment.


1972 ◽  
Vol 79 (1) ◽  
pp. 99-103 ◽  
Author(s):  
A. M. Raven

SUMMARYA 6 x 6 Latin Square balance experiment was carried out using six Friesian steers, each of which initially weighed about 304 kg. The six treatments studied were an all-hay diet and five other diets containing 20,40,60,80 and 100 % of rolled barley fortified with mineral and vitamin supplements, accompanied by correspondingly reduced proportions of hay. Each diet was fed at an estimated maintenance level of feeding.The progressive increase in the proportion of concentrate gave a significantly linear increase (P < 0·001) in both digestible and calculated metabolizable energy. The actual increase in digestible energy was from 2·62Mcal/kg dry matter (59·3% of the gross energy) on the all-hay treatment to 3·42 Mcal/kg dry matter (79·5% of the gross energy) on the all-concentrate treatment. Use of the determined digestible energy values for the all-hay and fortified barley diets to calculate the digestible energy of the four mixed diets gave results in reasonably good agreement with the determined values, the maximum difference being 0·12 Mcal/kg dry matter, which represented 3·83 % of the determined value. The losses of energy in the urine expressed as percentages of the gross energy of the diets showed a small but significantly linear decrease (P < 0·01) with increase in proportion of barley in the diet. The molar proportions of steamvolatile acids in samples of rumen fluid taken from two animals on each treatment indicated that increase in the proportion of concentrate was associated with tendencies for increase in acetic acid, decrease in propionic acid and little change in butyric acid. The mean digestibility of the organic matter was 62·6 % on the all-hay treatment and 81·8 % on the all concentrate treatment. The progressive increase in the proportion of concentrate gave a significantly linear increase (P < 0·001) in digestibility of the organic matter. Although intakes of nitrogen decreased with increase in the proportion of concentrate due to a decrease in the amount of dry matter fed, the weights of nitrogen retained were well maintained and when expressed as percentages of intake showed a significantly linear increase (P < 0·01).


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