The response of perennial ryegrass to nitrogen in various periods of the growing season

SUMMARYThe response of irrigated, perennial ryegrass to fertilizer nitrogen was studied in four consecutive periods of the growing season by applying 0–350 kg N/ha to a fresh sward at the start of each period, and measuring both herbage dry matter and its content of nitrogen.Responses in yield were highest in the first period, which ended at inflorescence emergence; in this period, both the percentage recovery of nitrogen and the extent of its utilization in producing dry matter were greater than in the later periods. Some damage to the sward was seen following the harvest of grass grown with the high levels of nitrogen in the first period. When the yields were 90% of the predicted maximum the nitrate-N content of the herbage ranged from 1000 to 2000 ppm, except in the first period when it was 200 ppm.The response curves were used to calculate the nitrogen requirements of the grass which would maintain given incremental yield responses. To produce near-maximum yields, irrigated grass swards may require fertilizer nitrogen equivalent to 2 kg N/ha/day prior to inflorescence emergence, and up to 5 kg N/ha/day for the remainder of the growing season.The apparent efficiency of conversion of the radiant energy, usable for photosynthesis, into plant energy averaged 3·2%; it did not vary greatly among the four periods.The experimental results indicate the seasonal requirements of grass for fertilizer nitrogen and some of the implications for animal husbandry are discussed.

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Low rates of phosphorus fertiliser applied strategically throughout the growing season under rain-fed conditions did not affect dry matter production of perennial ryegrass (Lolium perenne L.)

Crop and Pasture Science ◽

10.1071/cp09259 ◽

2010 ◽

Vol 61 (5) ◽

pp. 353 ◽

Cited By ~ 12

Author(s):

L. L. Burkitt ◽

D. J. Donaghy ◽

P. J. Smethurst

Keyword(s):

Lolium Perenne ◽

Perennial Ryegrass ◽

Dry Matter ◽

Growing Season ◽

Dry Matter Production ◽

Pasture Production ◽

Lolium Perenne L ◽

Matter Production ◽

Extractable P ◽

Intensively Managed

Pasture is the cheapest source of feed for dairy cows, therefore, dairy pastures in Australia are intensively managed to maximise milk production and profits. Although soil testing commonly suggests that soils used for dairy pasture production have adequate supplies of phosphorus (P), many Australian dairy farmers still apply fertiliser P, often by applying smaller rates more frequently throughout the year. This study was designed to test the hypotheses that more frequent, but lower rates of P fertiliser applied strategically throughout the growing season have no effect on dry matter production and P concentration in perennial ryegrass (Lolium perenne L.), when soil extractable P concentrations are above the critical value reported in the literature. Three field sites were established on rain-fed dairy pasture soils ranging in P sorption capacity and with adequate soil P concentrations for maximising pasture production. Results showed that applied P fertiliser had no effect on pasture production across the 3 sites (P > 0.05), regardless of rate or the season in which the P was applied, confirming that no P fertiliser is required when soil extractable P concentrations are adequate. This finding challenges the viability of the current industry practice. In addition, applying P fertiliser as a single annual application in summer did not compromise pasture production at any of the 3 sites (P > 0.05), which supports the current environmental recommendations of applying P during drier conditions, when the risk of surface P runoff is generally lower. The current results also demonstrate that the short-term cessation of P fertiliser application may be a viable management option, as a minimal reduction in pasture production was measured over the experimental period.

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Yield and protein responses to nitrogen, and nitrogen fertiliser requirements of grain sorghum, in relation to soil nitrate levels

Australian Journal of Agricultural Research ◽

10.1071/a97003 ◽

1997 ◽

Vol 48 (8) ◽

pp. 1187 ◽

Cited By ~ 5

Author(s):

I. C. R. Holford ◽

J. F. Holland ◽

A. J. Good ◽

C. Leckie

Keyword(s):

Yield Response ◽

N Recovery ◽

Soil Nitrate ◽

Soil N ◽

Response Curves ◽

The North ◽

Nitrate N ◽

South Wales ◽

Yield Responses ◽

Protein Response

Sorghum fertiliser experiments at 40 sites on the north-western slopes andplains of New South Wales demonstrated that many soils are severely deficientin nitrogen (N), but most yield responses to fertiliser N occurred on sites inthe southern part of the region. Grain yields responded to fertiliser in fewerthan half of the experiments but protein concentrations responded in about75%.There were 4 distinct types of protein response curve, and the type of curvewas related to the degree of N deficiency. In the most deficient experiments(mean protein 6·1% or less), response curves were convex to thex -axis or linear; at intermediate deficiency (mean protein7·2%), response curves were sigmoid; and at low deficiency (meanprotein 9·7%), response curves were Mitscherlich. Yield responsenever occurred where grain protein was >10%.Maximum grain yield responses and amounts of fertiliser N for maximum profit,estimated by fitting the Mitscherlich equation to response curves, weresignificantly correlated with soil nitrate N levels at various depths in thesouthern experiments, but not in the northern experiments. This difference inN responses appeared to be caused by lower rainfall and higher soil N in mostof the northern experiments. Nitrate-N levels in soils sampled to 15 or 30 cmdepth were better correlated with yield response ( r> 0·81) and fertiliser requirement (r >0·72) than N levels to deeper depths.There was little or no fertiliser N recovery in the grain in the northern experiments but substantial recovery in the south where it was generallygreater than recovery by wheat in earlier experiments in the same region.Fertiliser requirement in relation to soil nitrate-N levels was lower thanthat of these wheat experiments. This was attributed to mid-spring soilsampling for sorghum which underestimates the soil N available to the sorghum

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The effect of a wide range of fertilizer nitrogen application rates and defoliation intervals on the dry-matter production, seasonal response to nitrogen, persistence and aspects of chemical composition of perennial ryegrass (Lolium perennecv. S.24)

The Journal of Agricultural Science ◽

10.1017/s0021859600037424 ◽

1977 ◽

Vol 88 (3) ◽

pp. 711-721 ◽

Cited By ~ 31

Author(s):

P. W. Bartholomew ◽

D. M. B. Chestnutt

Keyword(s):

Dry Matter ◽

Maximum Yield ◽

Ground Cover ◽

Growing Season ◽

Nitrate Content ◽

Nitrogen Application ◽

Fertilizer Nitrogen ◽

Application Rates ◽

Wide Range ◽

Small Plot

SUMMARYA small-plot experiment was made to assess the influence on dry-matter output from grass of a wide range of fertilizer nitrogen and defoliation interval treatments. There were five defoliation treatments, 22, 28, 45, 75 and 112-day regrowth intervalsroughout the growing season each at six levels of nitrogen application, ranging by 300 kg increments from 0 to 1500 kg/ha/year.There was a marked interaction effect between treatments; a positive dry-matter response was maintained to a higher level of applied nitrogen with more frequent defoliation. In 2 years out of 3 maximum dry-matter yield was produced under a 75·day defoliation interval although the mean yield advantage over a 45-day defoliation system was only 11%. Mean yield of digestible dry matter appeared to reach a maximum under a 45·day defoliation interval at 600 kg N/ha but at the lower levels of N the maximum yield was reached at the longest growth interval.Seasonal response to nitrogen under the 22–day and 28–day defoliation systems measured as the increase in yield resulting from increased N at each cutting date reached its peak in July–August. Application for these short growth periods early and late in the growing season appeared to be a relatively inefficient use of nitrogen.The less frequently the sward was harvested and the higher the nitrogen application the greater was the reduction in ground cover as estimated by eye at the end of the growing season, this reached an estimated 25% reduction under 112·day defoliation at 300 kg N/ha/year.In relation to published figures nitrate content of herbage did not reach dangerous levels until nitrogen application reached levels beyond those at which maximum dry·matter yield was achieved.

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Seasonal and genetic variations in water-soluble carbohydrates and other quality traits in ecotypes and cultivars of perennial ryegrass (Lolium perenneL.)

Plant Genetic Resources ◽

10.1017/s1479262113000567 ◽

2013 ◽

Vol 12 (2) ◽

pp. 236-247 ◽

Cited By ~ 2

Author(s):

Sarah McGrath ◽

Trevor R. Hodkinson ◽

Andreas Frohlich ◽

Jim Grant ◽

Susanne Barth

Keyword(s):

Genetic Resources ◽

Perennial Ryegrass ◽

Dry Matter ◽

Growing Season ◽

Water Soluble ◽

Soluble Carbohydrates ◽

Soluble Carbohydrate ◽

Time Points ◽

Sequencing Technologies ◽

Breeding Programmes

Phenotyping of genetic resources remains the bottleneck in the characterization of genetic resources, since the advent of modern next-generation sequencing technologies has made genotyping much more cost- and time-effective. This article reports on the phenotyping of agriculturally important traits in perennial ryegrass (Lolium perenne). In the present study, water-soluble carbohydrate (WSC), crude protein and dry matter contents were recorded for 1320 individuals, pooled into 132 samples from 33 perennial ryegrass ecotypes and cultivars at five different harvest time points across the 2004 growing season. While, in general, the cultivars had higher WSC contents than the ecotypes, individual ecotypes did show potential to be used in breeding programmes, as they had higher values than all other accessions at particular cutting time points. In correlation analyses, positive relationships were observed between dry matter and glucose contents both early and late in the growing season. Principal components analysis allowed the split either between cultivars and ecotypes or between tetraploid cultivars and the rest of the accessions at four of the five cutting time points. In the analysis of variance, cutting time was the most significant factor influencing the variation in traits.

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The effects of fertilizers on herbage production Part I. The effect of nitrogen, phosphate and potash on yield

The Journal of Agricultural Science ◽

10.1017/s0021859600023765 ◽

1961 ◽

Vol 56 (1) ◽

pp. 17-29 ◽

Cited By ~ 34

Author(s):

J. W. S. Reith ◽

R. H. E. Inkson ◽

A. B. Stewart ◽

W. Holmes ◽

D. S. Maclusky ◽

...

Keyword(s):

Dry Matter ◽

Annual Production ◽

First Year ◽

Plant Food ◽

Factorial Experiments ◽

Response Curves ◽

Nitrogen Rate ◽

Fertilizer Nitrogen ◽

N Treatment ◽

Production Part

The paper reports the results for six factorial experiments carried out over a period of 3 years, and designed to measure the effects of nitrogen, phosphate and potash on the yield of dry matter and to determine the effect of nitrogen on the phosphate and potash requirements of grass being cut five times per annum for conservation.Heavy dressings of nitrogen reduced the percentage of dry matter in the fresh herbage, but produced a very large increase in the yield of dry matter. There were quite large variations in the response to this plant food, but 348 lb. N per acre per annum practically doubled the yield and generally the response curves were substantially linear.The response to nitrogen depended on an adequate supply of potash and at five of the centres there were very large interactions between these two nutrients. The need for potash was greatest at the highest nitrogen rate and was much greater in the second and third than in the first year of the experiments.At the highest nitrogen rate some of the responses to potash were very large. The yields of dry matter showed no large or consistent differences between applying 336 lb. K2O in one dressing during the winter months or applying this amount in five equal dressings, one for each cut. The results demonstrated the ability of the soils to supply potash and showed that the regular cutting and removal of herbage, especially if heavy dressings of nitrogen were applied, exhausted the potash reserves in the soil.Phosphate had practically no effect on the yield of dry matter either in the presence or absence of nitrogen.With adequate potash the production of dry matter per lb. of fertilizer nitrogen was practically independent of rate and the overall mean results are between 14·0 and 15·7 lb. In the absence of fertilizer potash there was a very large effect of rate: 15·0 lb. dry matter per acre was produced per lb. N with the 87 lb. N per annum treatment, 13·7 lb. with 174 lb. N and 10·0 lb. with the 348 lb. N treatment.Approximately 70–75% of the annual production was obtained before the end of July. Thus 1 lb. of fertilizer nitrogen produced considerably more dry matter per acre during May, June and July than later in the season.

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The comparison of five response curves for representing the relationship between the annual dry-matter yield of grass herbage and fertilizer nitrogen

The Journal of Agricultural Science ◽

10.1017/s0021859600038910 ◽

1979 ◽

Vol 93 (3) ◽

pp. 513-520 ◽

Cited By ~ 23

Author(s):

P. E. Sparrow

Keyword(s):

Dry Matter ◽

Dry Matter Yield ◽

Response Curves ◽

Fertilizer Nitrogen ◽

The Relationship

SUMMARYThe results of 84 experiments with six levels of nitrogen were used to investigateresponse curves relating the dry-matter yield of grass herbage to fertilizer nitrogen. Of the five curves tested, the inverse quadratic represented the relationship well, although no one curve fitted best on all experiments.

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Effect of second pond dairy effluent applied in spring to silage regrowth of perennial ryegrass based pasture in southern Australia. 1. Dry matter yield and botanical composition changes

Australian Journal of Agricultural Research ◽

10.1071/ar06159 ◽

2007 ◽

Vol 58 (2) ◽

pp. 137 ◽

Cited By ~ 7

Author(s):

J. L. Jacobs ◽

G. N. Ward

Keyword(s):

Perennial Ryegrass ◽

Dry Matter ◽

Standard Treatment ◽

Growing Season ◽

Soil Characteristics ◽

Linear Increase ◽

Primary Response ◽

Botanical Composition ◽

Dairy Effluent ◽

Composition Changes

In southern Australia the standard treatment system for dairy shed effluent is a 2-pond system. Effluent from the dairy is first treated in a deep anaerobic pond where sedimentation and breakdown of organic matter occur. Treated liquid effluent then enters a shallow aerobic pond where it is stored. Relatively little information is available on forage agronomic responses to application of this second pond liquid. The effect of applying this second pond dairy effluent to perennial ryegrass based pasture was measured over a 3-year period. Effluent was applied at 6 rates: 0, 15, 30, 45, 60, and 75 mm following spring silage harvest each year. Changes to herbage dry matter (DM) accumulation, and botanical composition were determined at each subsequent grazing. Over the 3 years of application, the average concentrations of phosphorus, potassium, and sulfur in the effluent were 31, 454, and 20 kg/ML, respectively. In addition, the effluent contained 149 kg/ML of nitrogen and 529 kg/ML of sodium. For all 3 years, the application of effluent resulted in a linear increase (P > 0.05) in annual herbage DM accumulation. Response rates for the 3 years were 27, 22, and 9 kg DM/mm applied effluent, respectively. The majority of this response occurred by the first grazing after application, where effluent application gave rise to linear responses (P > 0.05) in herbage DM accumulation of 17, 18, and 7 kg DM/mm for Years 1, 2, and 3, respectively. Botanical composition was not significantly affected by effluent application. This experiment has highlighted the potential of using second pond dairy effluent following pasture harvesting for silage as a means to grow additional herbage and extend the growing season. Based on the N content of effluent, herbage DM accumulation responses (Year 1, 10.4; Year 2, 11.4; Year 3, 5.1 kg DM/kg N) were similar to those expected from application of fertiliser N. It is likely that the primary response in terms of herbage accumulation is due to the N component within dairy effluent. While this study has shown positive herbage DM accumulation responses to applied effluent, further work is required to determine longer term effects of repeated effluent application, especially sodium, to soil characteristics.

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