The effects of ozone and nitrogen fertilizer on tall fescue, ladino clover, and a fescue–clover mixture. II. Nitrogen content and nitrogen fixation

1983 ◽  
Vol 61 (8) ◽  
pp. 2159-2168 ◽  
Author(s):  
Ruben A. Montes ◽  
Udo Blum ◽  
Allen S. Heagle ◽  
Richard J. Volk

The effects of chronic doses of ozone (O3) and rates of nitrogen (N) fertilizer on N content of ladino clover (Trifolium repens L. cv. Tillman) and tall fescue (Festuca arundinacea Schreb. cv. Kentucky 31), and on N fixation by the clover were studied during the 1979 growing season. Plants of the two species were grown (i) in pots separately, (ii) together in open-top field chambers, and (iii) in ambient air plots. Mean 7 h/day (0930–1630 h eastern daylight time) O3 concentrations for the study period were 0.03 ppm in charcoal-filtered air chambers, 0.05 ppm in nonfiltered air chambers, 0.08 ppm in nonfiltered air chambers with O3 added for 7 h/day, and 0.05 ppm in ambient air. Shoot N concentrations (milligrams per gram dry weight) for clover and fescue were not modified by O3 exposures nor by N fertilization. Higher ozone levels led to reduced system N fixation (milligrams N per pot) by clover grown separately or together with fescue. Nitrogen fixation by ladino clover grown with tall fescue was 1.4 times greater than that by the clover grown alone. Nitrogen fixation by clover as estimated by the difference method was approximately 45% lower than N fixation as estimated by the 15N dilution method. Nitrogen fixation estimated by the difference method declined significantly with increasing N fertilization. This was not the case for N fixation estimated by the 15N dilution method.

1986 ◽  
Vol 56 (1) ◽  
pp. 131-140 ◽  
Author(s):  
T. Varvikko

1. In the previous work (Varvikko & Lindberg, 1985), 15N-labelled rapeseed (Brassica napus), barley, ryegrass (Lolium perenne) and barley straw were incubated in the rumen in nylon bags for 5, 12 and 24 h and microbial nitrogen in the residues was quantified using the feed 15N-dilution method. In the present study, residual amino acids (AA) of these feeds were analysed, and microbially corrected AA of feed origin (feed AA) were estimated as the difference between total residual AA and respective microbial AA, assuming a constant AA composition for the microbial protein.2. In barley and barley-straw residues, and also in ryegrass incubated in the rumen for 24 h, very large enrich- ment by microbial N and AA-N was found. The microbial enrichment was rather small in rapeseed residues and ryegrass incubated for 5 or 12 h. During the rumen incubation, feed N and AA-N (g/kg feed dry matter (DM)) decreased very clearly in all the feeds, and feed and incubation time effects were always statistically significant (P < 0.001).3. The slow degradation of essential (E) feed AA compared with the respective non-essential (NE) AA degradation increased the proportion of feed EAA (g/kg determined feed AA) in barley and barley-straw residues. In rapeseed and ryegrass, residual feed EAA: NEAA remained very similar to the original. Branched-chain (Br) AA tended to increase proportionally in all the feed residues, suggesting these AA to be, on average, more resistant against microbial degradation in the rumen than other AA. Similarly, lysine was clearly increased in barley residues. A rumen degradation faster than the average rate caused decreased residual feed glutamic acid in rapeseed; methionine, alanine and glycine in barley; arginine and alanine in ryegrass; and methionine, asparagine and tyrosine in barley straw. Feed and incubation time effects were significant (P < 0.054–001) for feed AA (g/kg determined feed AA) grouped as EAA, BrAA or NEAA, and for most individual AA, as well as for feed AA disappearance (%) and relative amounts (%) of feed AA in the respective residual AA.4. According to present findings, AA composition of the rumen-undegraded vegetable feed residues may markedly differ, either quantitatively or qualitatively (or both), from their original AA composition. When determining the feed AA composition of nylon-bag residues, the microbial error may be very large with starchy or fibrous feeds of low protein content. The microbial AA do not, however, considerably confuse the AA determination of protein-rich feeds.


HortScience ◽  
1993 ◽  
Vol 28 (10) ◽  
pp. 1015-1016 ◽  
Author(s):  
B.J. Johnson

Pendimethalin and oxadiazon are used commonly to control crabgrasses (Digitaria spp.) in tall fescue (Festuca arundinacea Schreb.) and common bermudagrass [Cynodon dactylon (L.) Pers.]. A field experiment was conducted for 2 years to determine if reduced pendimethalin and oxadiazon application rates would control large crabgrass [D. sanguinalis (L.) Sco.] effectively in tall fescue and common bermudagrass. Oxadiazon applied at 1.1 kg a.i./ha in each of two applications at a 60-day interval (less than recommended rate) effectively controlled large crabgrass (≥93%), regardless of turfgrass species. Pendimethalin applied at 1.1 kg a.i./ha in each of two applications controlled large crabgrass in common bermudagrass effectively (≥90%) but not large crabgrass in tall fescue (47%). The difference in pendimethalin performance between the two species was attributed to the ability of common bermudagrass to compete more successfully than tall fescue with large crabgrass during late summer. Chemical names used: 3-[2,4-dichloro-5-(1-methylethoxy)phenyl]-5-(1,1-dimethylethy1)-l,3,4-oxadiazol-2-(3 H)-one (oxadiazon); N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine (pendimethalin).


HortScience ◽  
1991 ◽  
Vol 26 (11) ◽  
pp. 1391-1392 ◽  
Author(s):  
A.D. Brede

A field study was conducted to evaluate the effect of tall fescue (Festuca arundinacea Schreb.) cultivar, seeding rate, N fertilization rate, and cutting height on the severity of dollar spot (Lanzia and Moellerodiscus spp.) disease incidence. All possible two-factor interactions among these four management factors were statistically significant when averaged over the 2 years of study. Disease severity tended to be lowest at low fescue seeding rate (2100 pure-live seeds/m*) at the lower (19 mm) height of cut. `Mustang', the turf-type cultivar with improved density, was more susceptible to dollar spot than `Kentucky-31', the common-type cultivar.


Author(s):  
T.G. Judd ◽  
N.A. Thomson ◽  
D.A. Mccallum

Dry matter (DM) production and seasonal distribution of old ryegrass/white clover pasture defoliated at 14- and 28day intervals, and new sowings of 'Grasslands Maru' phalaris (Phaluris aquatica L.), 'Grasslands Roa' tall fescue (Festuca arundinacea Schreb.), and 'Grasslands Kara' cocksfoot (Dactylis glomerata L.) at 28day defoliation intervals were evaluated in an environment prone to grass grub damage and dry summer/autumn periods. Under a 28&y defoliation interval old ryegrass produced 2O%more DM that the 14-day defoliation interval, the difference occuring mainly in spring. Annual production, in the initial 4 years, of phalaris and tall fescue was respectively 17 % and 20 % more than that of old ryegrass. Phalaris was superior to old ryegrass in all seasons. Cocksfoot annual production was similar to that of old ryegrass, producing more in summer (9%) and autumn (19%) but 15% less in spring. Results from year 5 and 6 suggest that phalaris may not be as persistent as tall fescue. A 28-day rotation in spring is recommended to maximise production of old ryegrasslclover pasture. Phalaris and tall fescue are recommended as alternative species to old ryegrass in a grass grub prone and/or summer dry environment. Cocksfoot is not recommended. Keywords pasture production, seasonal distribution, cow requirements, old ryegrass, phalaris, tall fescue, cocksfoot


1997 ◽  
Vol 129 (1) ◽  
pp. 19-31 ◽  
Author(s):  
D. E. HUME ◽  
J. L. BROCK

The effects of contrasting management systems either of infrequent rotational grazing by town milk supply dairy cattle, or of frequent defoliation by continuously grazing sheep and beef cattle, on the morphology of independent plants and populations of ‘Grasslands Roa’ tall fescue in mixed pastures, were measured over 1 year (1992/93) in New Zealand. Volunteer perennial ryegrass plants were also measured for comparison.While both species exhibited a similar pattern of clonal growth, tall fescue developed more plants of higher branching complexity than perennial ryegrass, chiefly through maintaining more connective stems, as herbage production was confined to the three youngest branching orders in both species. Greater resistance to microbial degradation of old stems through poorer quality organic matter (wide C[ratio ]N ratio) compared to perennial ryegrass may be responsible for the greater complexity of fescue plants. In addition, tillering rates in tall fescue were three times lower which was offset by greater longevity and size of leaves and tillers, compared to perennial ryegrass. As a result, seasonal fluctuation in the distribution of plants among the various branching orders in tall fescue was small, producing a more stable population relative to the distinct seasonal changes in the population of perennial ryegrass plants. Grazing management had no effect on the seasonal population structure in either species.Differences in plant structure due to grazing management were small, with only slightly more tillers on sheep-grazed than on cattle-grazed tall fescue plants. The major effect of grazing management was on dry weight or size of plant components. Cattle-grazed tall fescue plants were 120% heavier, with greater numbers and lengths of stolons and flower heads than those under sheep grazing. For the volunteer perennial ryegrass, the difference was only 65%, possibly due to competition from the more vigorous tall fescue under rotational cattle grazing.Both species produced stolons throughout the year, although these were primarily associated with reproductive growth in spring. In tall fescue, an additional distinction was made between stolon and rhizome, the latter occurring mainly in the summer–autumn. Their possible functions in plant growth are discussed.


Author(s):  
J. Monk ◽  
E. Gerard ◽  
S. Young ◽  
K. Widdup ◽  
M. O'Callaghan

Tall fescue (Festuca arundinacea) is a useful alternative to ryegrass in New Zealand pasture but it is slow to establish. Naturally occurring beneficial bacteria in the rhizosphere can improve plant growth and health through a variety of direct and indirect mechanisms. Keywords: rhizosphere, endorhiza, auxin, siderophore, P-solubilisation


Author(s):  
B.R. Watkin

AN Aberystwyth selection of tall fescue (Festuca arundinacea Schreb.), known as S170, was sown with certified New Zealand white clover (Trifolium repens) and re' clover (T. pratense) and compared under sheep grazing with other grass/clover pastures at the Grasslands Division Regional Station at Lincoln (Watkin, 1975) .


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