The use of repeated measurements analysis for the evaluation of seasonal variation in the dry matter yield and nutritive value of perennial ryegrass (Lolium perenne L.) cultivars

1998 ◽  
Vol 38 (2) ◽  
pp. 145 ◽  
Author(s):  
K. F. Smith ◽  
G. A. Kearney ◽  
R. A. Culvenor
Keyword(s):  
Seasonal Variation ◽  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
Dry Matter ◽  
Nutritive Value ◽  
Repeated Measurements ◽  
Water Soluble ◽  
Lolium Perenne L ◽  
Harvest Dates ◽  
Serial Correlations

Summary. Seasonal variation in herbage yield, and in the concentrations of water-soluble carbohydrates, crude protein, in vitro dry matter digestibility, neutral detergent fibre, acid detergent fibre and lignin in the herbage was measured for 5 perennial ryegrass (Lolium perenne L.) cultivars grown in 3 contrasting environments. Two separate trials were sown in one of the environments. The yield and nutritive value data were subjected to antedependence analyses to detect the presence of serial correlations between data from different harvest dates. Significant (P<0.05) antedependence was found in 2, 3, 3 and 6 of the 7 variables in the 4 experiments respectively. It was shown that serial correlations between harvest dates had the potential to cause the overestimation of the significance of cultivar effects in ANOVA of data from individual harvest dates, and in harvest and cultivar × harvest effects in combined ANOVA across all harvest dates unless statistical procedures appropriate for use with repeated measurements data were adopted.

scholarly journals Thermal Time as a Parameter to Determine Optimal Defoliation Frequency of Perennial Ryegrass (Lolium perenne L.) and Pasture Brome (Bromus valdivianus Phil.)

Agronomy ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 620 ◽  
Author(s):  
Iván Calvache ◽  
Oscar Balocchi ◽  
Máximo Alonso ◽  
Juan Pablo Keim ◽  
Ignacio F. López
Keyword(s):  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
Dry Matter ◽  
Leaf Growth ◽  
Metabolizable Energy ◽  
Water Soluble ◽  
Neutral Detergent Fiber ◽  
Thermal Time ◽  
Soluble Carbohydrates ◽  
Lolium Perenne L

The herbage mass and nutritional value of harvested forage are fundamental determinants of the production potential of pastoral systems. The objective of this study was to evaluate the growth dynamics and accumulated herbage mass expressed in dry matter (DM) of perennial ryegrass (Lolium perenne L.) and pasture brome (Bromus valdivianus Phil.) pastures, using thermal time (TT) as a defoliation criterion. Thirty plots (15 of L. perenne and 15 of B. valdivianus) were distributed in three field blocks and subjected to five defoliation frequencies (DF) determined by TT, expressed as the accumulated growing degree-days (AGDD; DF1 = 90, DF2 = 180, DF3 = 270, DF4 = 360, and DF5 = 450 AGDD) for one year (2016), at the Austral Agricultural Experimental Station of the Universidad Austral de Chile. Every three days, the total leaf length (TLL) was measured, and the leaf elongation rate (LER, cm L−1), leaf growth rate (LGR, cm L−1), leaf appearance rate (LAR, d L−1), phyllochron (AGDD L−1), and accumulated herbage mass per hectare (kg DM ha−1) were calculated. Defoliations were scheduled according to AGDD, and a sample was taken from each cutting to determine (dry matter ‘DM’, crude protein ‘CP’, neutral detergent fiber ‘NDF’, acid detergent fiber ‘ADF’, water-soluble carbohydrates ‘WSC’ and metabolizable energy ‘ME’). The pastures that were allocated to DF5 presented higher DM yields (12,600 kg DM ha−1 year−1), TLL (54.6 cm), and LER (0.63 cm d−1) compared to pastures with high DF (90 and 180 ADGG). B. valdivianus presented a lower phyllochron than L. perenne (74.4 vs 87.9 AGDD L−1, respectively). Concentrations of CP and ME decreased from the shortest DF (90 AGDD) to the largest DF (450 AGDD), dropping from 221 to 138 g kg−1 CP and from 2.6 to 2.4 Mcal kg−1 DM of ME. All variables were affected by the season (Ssn) (p < 0.001). The AGDD can be used as a defoliation criterion and a tool to balance yield with nutritive value according to the farmer’s needs.

The effect of biological additives on the composition and nutritive value of silage

1990 ◽  
Vol 1990 ◽  
pp. 139-139
Author(s):  
M Gonzalez Yanez ◽  
R Mcginn ◽  
D H Anderson ◽  
A R Henderson ◽  
P Phillips
Keyword(s):  
Cell Wall ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
Nutritive Value ◽  
Enzyme System ◽  
Lolium Perenne L ◽  
Grass Silage ◽  
Forage Harvester

It Is claimed that the use of the correct enzyme system as an additive on grass silage will satisfactorily control the fermentation and reduce the cell-wall fibre content, thus preserving the nutrients In the silage and aiding their utilisation by the animal (Henderson and McDonald, 1977; Huhtanen et al, 1985; Raurama et al, 1987; Chamberlain and Robertson, 1989; Gordon, 1989;).The aim of the present experiment was to assess the effect of biological additives, enzymes or a combination of enzymes with an Inoculum of lactic acid bacteria, on the composition of silage and on its nutritive value when offered to store lambs as the sole constituent of their diet.On 1st June 1988, first cut perennial ryegrass (Lolium perenne L) at pre-ear emergence was ensiled direct cut untreated (U), treated with a commercial enzyme (E) or with a commercial inoculum of lactic acid bacteria with enzymes (I) in 6t capacity bunker silos. The grass was cut with a mower and lifted with a New Holland precision chop forage harvester. The additives were pumped onto the grass using a dribble bar sited over the pick-up drum.

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.)

2010 ◽  
Vol 61 (5) ◽  
pp. 353 ◽  
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.

Regrowth of prairie grass (Bromus willdenowii Kunth) and perennial ryegrass (Lolium perenne L.) in response to temperature and defoliation

2000 ◽  
Vol 51 (5) ◽  
pp. 555 ◽  
Author(s):  
K. Slack ◽  
W. J. Fulkerson ◽  
J. M. Scott
Keyword(s):  
High Temperature ◽  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
Growth Rates ◽  
Water Soluble ◽  
The Other ◽  
Effect Of Temperature ◽  
Lolium Perenne L ◽  
Leaf Stage ◽  
Prairie Grass

This glasshouse study was undertaken to determine the effect of temperature and defoliation on the regrowth of prairie grass (Bromus willdenowii Kunth cv. Matua) in comparison with perennial ryegrass (Lolium perenne L. cv. Dobson). Individual plants of prairie grass and perennial ryegrass were grown in 2 mini-swards with one half as prairie grass and the other as ryegrass. From H0 (13 weeks after sowing) to the completion of the experiment at H3, one sward was maintained at a day/night temperature of 18/10˚C and the other at 25/15˚C. From H0 to H1, prairie grass was defoliated 4 times at the time taken to regrow 1 new leaf per tiller (1-leaf stage), 2 times at the 2-leaf stage, or once at the 4-leaf stage to 60, 90, or 120 mm stubble height. Similarly, ryegrass was defoliated 3 times at the 1- leaf stage, once at the 1-leaf stage then once at the 2-leaf stage, or once at the 3-leaf stage to 30, 60, or 90 mm stubble height. Plants were subsequently harvested at H1, H2, and H3, being the commencement, mid-point, and completion of the full regrowth cycle (4- and 3-leaf stage for prairie grass and ryegrass, respectively). Prairie grass was more adversely affected by frequent defoliation than ryegrass. The combination of high temperature and frequent defoliation reduced growth rates by 66 v. 54%, stubble dry matter (DM) by 50 v. 11%, root DM by 62 v. 45%, and stubble water-soluble carbohydrate (WSC) by 52 v. 21% for prairie grass and ryegrass, respectively. In contrast, ryegrass was more affected by defoliation height than prairie grass, particularly at the higher temperature. Close defoliation and high temperature reduced growth rate by 35 v. 25%, root DM by 18 v. 0%, and stubble WSC by 84% v. 36% for ryegrass and prairie grass, respectively. The number of tillers per plant was reduced by close defoliation, more so at the high temperature in ryegrass but not in prairie grass. Defoliating prairie grass to 90 mm stubble height at the 4-leaf per tiller stage compared with the 1-leaf per tiller led to maximum restoration of stubble WSC reserves as well as maximising leaf and root growth. The higher stubble WSC and greater root DM of prairie grass, together with its ability to maintain growth rates and tillering under high temperature, are attributes which explain why prairie grass appears to be more productive and persistent than ryegrass in a subtropical environment.

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