Control of water leakage from below the root zone by summer-active pastures is associated with persistence, density and deep rootedness

2016 ◽  
Vol 67 (6) ◽  
pp. 679 ◽  
Author(s):  
M. R. McCaskill ◽  
G. A. Kearney

Temperate pastures that leak water below the root zone have been linked to an increase in dryland salinity in southern Australia through their conservative use of stored water. An experiment was conducted at Hamilton in south-western Victoria to test the hypothesis that deep-rooted, summer-active perennial pasture species can substantially reduce leakage. On topographic crests the experiment compared lucerne and chicory with a traditional perennial ryegrass variety with low summer activity, whereas on the poorly drained valleys the comparison was between tall fescue, kikuyu and a perennial ryegrass variety with high summer activity. Lucerne developed a buffer of dry soil to a depth of at least 5 m. An empirical relationship with June–September rainfall indicated that with this dry buffer, leakage below the root zone would not occur even in the wettest of years. Chicory developed a dry buffer to the depth of measurement (3 m), but plant density gradually declined and leakage started to occur 5 years after sowing. The perennial ryegrass with low summer activity had leakage nearly every year. On the valleys kikuyu was initially the most effective at drying the soil in summer, but its density declined at the expense of annuals and 3 years after sowing it became wetter than the other treatments. None of the pasture options on the valley fully controlled leakage, but both the summer-active perennial ryegrass and tall fescue were persistent and there was little difference in their capacity to extract summer moisture. This study showed that four characteristics were associated with a pasture that controlled leakage – summer activity, persistence, adequate density and deep rootedness. Of the species tested only lucerne satisfied all these criteria.

Crop Science ◽  
1992 ◽  
Vol 32 (6) ◽  
pp. 1366-1370 ◽  
Author(s):  
W. W. Xu ◽  
David A. Sleper ◽  
S. Chao

1997 ◽  
Vol 11 (1) ◽  
pp. 24-29 ◽  
Author(s):  
Clyde L. Elmore ◽  
Victor A. Gibeault ◽  
David W. Cudney

Overseeding established kikuyugrass swards with tall fescue or perennial ryegrass reduced kikuyugrass cover. Renovation prior to seeding did not aid in the establishment of these two species. Increasing the seeding rate from 79 to 157 kg/ha improved the establishment of perennial ryegrass but not tall fescue. When kikuyugrass plugs were introduced into established turf, tall fescue reduced the invasion of kikuyugrass stolons more than perennial ryegrass. Tall fescue reduced percent kikuyugrass cover, number and spread of stolons, and biomass (compared to perennial ryegrass). The newer turf-type tall fescue cultivars ‘Bonsai,’ ‘Falcon,’ and ‘Olympic’ were more effective than the older tall fescue cultivar ‘Fawn’ in reducing kikuyugrass invasion by reducing stolon number, stolon length, and biomass.


2010 ◽  
Vol 24 (4) ◽  
pp. 440-445 ◽  
Author(s):  
Daniel T. Earlywine ◽  
Reid J. Smeda ◽  
Travis C. Teuton ◽  
Carl E. Sams ◽  
Xi Xiong

Oriental mustard seed meal (MSM), a byproduct generated by pressing the seed for oil, exhibits herbicidal properties. In turfgrass, soil fumigants such as methyl bromide are used to control weeds prior to renovation of turf. Environmental concerns have resulted in deregistration of methyl bromide, prompting the need for alternatives. The objective of this research was to determine the effect of MSM on the establishment of selected turfgrass weeds as well as inhibitory effects on establishment of desirable turfgrasses. Greenhouse experiments were conducted in 2006 and 2007 at the University of Missouri. MSM was amended in soil at 0, 1,350 (low), 2,350 (medium), and 3,360 kg ha−1(high) concentrations. Weed species included annual bluegrass, large crabgrass, buckhorn plantain, white clover, and common chickweed. Turfgrass species included: Rembrandt tall fescue, Evening Shade perennial rye, and Riviera bermudagrass. All species were seeded into soil amended with MSM and either tarped or left untarped. All treatments were compared to dazomet (392 kg ha−1), a synthetic standard. Plant counts and biomass of all species were recorded 4 wk after seeding. Overall, tarped treatments suppressed weed emergence 27 to 50% more compared to untarped treatments, except for large crabgrass. High rates of MSM suppressed emergence of all weeds ≥ 63%. Compared to the untreated control, the density of buckhorn plantain, white clover, and common chickweed was reduced by ≥ 42% at low rates of MSM. Biomass of buckhorn plantain, annual bluegrass, common chickweed, white clover, and large crabgrass was reduced from 37 to 99% at high rates of MSM. MSM at high rates reduced stand counts of tall fescue and perennial ryegrass up to 81% and 77% respectively, compared to the untreated control. Regardless of MSM rates or tarping, suppression of common bermudagrass emergence did not exceed 30%; tarped treatments actually increased bermudagrass emergence by 22%. The biomass for tall fescue, perennial ryegrass, and bermudagrass was reduced by 85, 68, and 10%, respectively, at high rates of MSM. For tall fescue, MSM at all rates strongly suppressed seed germination by 7 d after planting (DAP) (up to 100%), with additional germination observed through 14 DAP, but not thereafter. In both trials, dazomet completely suppressed emergence of all weeds. MSM appears to suppress emergence and growth of a number of weeds common in turf, with potential selectivity for bermudagrass.


2003 ◽  
Vol 9 ◽  
pp. 25-40
Author(s):  
A.M. Nicol ◽  
T.N. Barry

Pasture is the primary feed source for NZ deer production with the greatest proportion grazed in situ. The quantity and quality of the pastures available to grazing deer varies markedly as a result of environmental factors and feed planning decisions by deer farmers. The grazing behaviour of deer responds to changes in pasture height and mass and the effect of pasture variables (height, pre -and post-grazing pasture mass and pasture allowance) on deer productivity are presented. These show that maximum levels of deer production from pasture will be achieved at a pasture height of around 8 cm (continuously stocked or post-grazing) although there is some evidence that for large genotypes, higher pasture availability is required. The relationship of liveweight gain of young deer with pasture availability shows marked seasonal effects. At the same level of pasture availability liveweight gain in spring is about twice that in winter, with autumn and summer intermediate. Increasing pasture availability cannot compensate for seasonal differences in liveweight gain. Furthermore, liveweight gain increases at a greater rate in spring than winter to increasing pasture availability, thus it is more important that appropriate pasture allowances are provided in spring than in winter. There is more variability in liveweight gain at a similar pasture availability in summer than in other seasons because of the greater variation in pasture quality in summer with the potential accumulation of seedheads and dead material. Alternative forage species are used in deer production for times of the year when quantity and quality of perennial ryegrass-based pastures limit productivity. Relative to weaner red deer grazed on perennial ryegrass/ white clover pasture, grazing on pure swards of red clover or chicory increased growth during autumn by 26-47% and during spring by 10-14%. The proportion of stags attaining target slaughter liveweight at 12 months of age increased from 75 to 94%. Pre-weaning growth during lactation was increased by approximately 20%. Red clover and chicory produce a greater proportion of their total DM during late summer and autumn than does perennial ryegrass/white clover pasture, and are therefore better aligned with deer feed requirements, particularly those of lactating hinds. Grazing on sulla in autumn and spring increased the growth of weaner deer by 33 and 10%, relative to pasture fed deer. Indoor studies showed that relative to perennial ryegrass, chicory was of higher organic matter digestibility, disintegrated more rapidly in the rumen with a low rumination time and had shorter mean retention time of material in the rumen. This explains differences in voluntary feed intake which were 56, 26 and 15% higher for deer grazing chicory than perennial ryegrass/white clover pastures during summer, autumn and spring respectively. Similar r esults have been found for the digestion of red clover versus perennial ryegrass by red deer. Plant density in stands of both chicory and red clover declines with time, with their lifetime under deer grazing being approximately 4 years. A mixture of both plants offers a food option as specialist forage for increasing deer growth and also fixing nitrogen. To ensure good persistence such forages should not be grazed in periods of prolonged wet weather. Best persistence is obtained when these are managed as specialist forages for increasing deer growth on a small area of the farm, (10- 20% total area), rather than being sown as a mixture with grasses over large areas of the farm. There is no specific comparison of deer production under different stocking systems and both continuous grazing and rotational grazing are used. Based on evidence and practices with other species, choice of stocking system has more to do with pasture/forage species, feed budgeting, pasture management and animal behaviour than with productivity. At high stocking densities (150 deer/ha), the grazing time of subordinate animals is reduced. Where possible, without inducing undue stress (e.g. at weaning), young deer should be grouped for grazing by liveweight. Deer production systems have a seasonal pattern of energy demand that does not match that of pasture growth in most NZ environments. This calls for manipulation of the feed demand by integration of livestock systems and/ or modification of the feed supply through conservation and supplementation. The most commonly used supplements are pasture and lucerne silage/baleage and grain. The quality (ME/kg DM) has a significant impact on the resulting liveweight gain.


2020 ◽  
Author(s):  
Jing Yan ◽  
Nathaniel A. Bogie ◽  
Teamrat Ghezzehei

Abstract. Most plants derive their water and nutrient needs from soils, where the resources are often scarce, patchy, and ephemeral. In natural environments, it is not uncommon for plant roots to encounter mismatched patches of water-rich and nutrient-rich regions. Such an uneven distribution of resources necessitates plants to rely on strategies that allow them to explore and acquire nutrients from relatively dry patches. We conducted a laboratory study to provide a mechanistic understanding of the biophysical factors that enable this adaptation. We grew plants in split-root pots that permitted precisely controlled spatial distributions of resources. The results demonstrated that spatial mismatch of water and nutrient availability does not cost plant productivity compared to matched distributions. Specifically, we showed that nutrient uptake is not reduced by overall soil dryness, provided that the whole plant has access to sufficient water elsewhere in the root zone. Essential strategies include extensive root proliferation towards nutrient-rich dry soil patches that allows rapid nutrient capture from brief pulses. Using high-frequency water potential measurements, we also observed nocturnal water release by roots that inhabit dry and nutrient-rich soil patches. Soil water potential gradient is the primary driver of this transfer of water from wet to dry soil parts of the root zone, which is commonly known as hydraulic redistribution (HR). The occurrence of HR prevents the soil drying from approaching the permanent wilting point, and thus supports root functions and enhance nutrient availability. Our results indicate that roots facilitate HR by increasing root-hair density and length and deposition of organic coatings that alter water retention. Therefore, we conclude that biologically-controlled root adaptation involves multiple strategies that compensate for nutrient acquisition under mismatched resource distributions. Based on our findings, we proposed a nature-inspired nutrient management strategy for significantly curtailing water pollution from intensive agricultural systems.


1990 ◽  
Vol 115 (4) ◽  
pp. 608-611 ◽  
Author(s):  
Jennifer M. Johnson-Cicalese ◽  
C.R. Funk

Studies were conducted on the host plants of four billbug species (Coleoptera:Curculionidae: Sphenophorus parvulus Gyllenhal, S. venatus Chitt., S. inaequalis Say, and S. minimus Hart) found on New Jersey turfgrasses. A collection of 4803 adults from pure stands of various turfgrasses revealed all four billbugs on Kentucky bluegrass (Poa pratensis L.), tall fescue (Festuca arundinacea Schreb.), and perennial ryegrass (Lolium perenne L.), and S. parvulus, S. venatus, and S. minimus on Chewings fescue (F. rubra L. ssp. commutata Gaud.). Since the presence of larvae, pupae, or teneral adults more accurately indicates the host status of a grass species, immature billbugs were collected from plugs of the various grass species and reared to adults for identification. All four species were reared from immature billbugs found in Kentucky bluegrass turf; immatures of S. venatus, S. inaequalis, and S. minimus were found in tall fescue; S. venatus and S. minimus in perennial ryegrass; and S. inaequalis in strong creeping red fescue (F. rubra L. ssp. rubra). A laboratory experiment was also conducted in which billbug adults were confined in petri dishes with either Kentucky bluegrass, perennial ryegrass, tall fescue, or bermudagrass (Cynodon dactylon Pers.). Only minor differences were found between the four grasses in billbug survival, number of eggs laid, and amount of feeding. In general, bermudagrass was the least favored host and the other grasses were equally adequate hosts. The results of this study indicate a need for updating host-plant lists of these four billbug species.


Author(s):  
A.G. Scott ◽  
D.W.R. White

Tissue culture was used in an attempt to obtain a fertile perennial ryegrass x tall fescue hybrid. Regenerated hybrid plants were found to be morphologically variable and contain extensive chromosome rearrangements. Spontaneous chromosome doubling had occurred as well as chromosome elimination. though no fertile hybrid plants have been obtained to date. Keywords: somaclonal variation, Lolium perenne, Festuca arundinacea, intergeneric hybrids


2011 ◽  
Vol 15 ◽  
pp. 157-162
Author(s):  
G.D. Milne

Recent discussion about pasture persistence concentrates on pastures based on perennial ryegrass, the most commonly used grass species. This paper raises the question as to whether some of the causes of poor pasture persistence are due to perennial ryegrass being used in environments to which it is not suited. The adaptation to environmental stresses, particularly water, temperature and nutrient deficiencies, in different regions of New Zealand of tall fescue, cocksfoot, phalaris, and lucerne are discussed, and how this impacts on persistence advantages over perennial ryegrass. Keywords: persistence, pasture, Dactylis glomerata, Festuca arundinacea, Lolium perenne, Medicago sativa, Phalaris aquatica


2021 ◽  
Vol 17 ◽  
Author(s):  
Tom Maxwell ◽  
Grant Edwards ◽  
Katherine Tozer ◽  
Gerald Cosgrove

Persistence is an important component of perennial pasture-grass productivity. Defining traits that affect persistence is essential for improving pasture longevity through plant breeding and for identifying persistence traits that should be included in cultivar ranking indices. Compared with conventional longitudinal studies, where a single sowing is monitored over time, repeated annual sowings allow the effects on persistence of sowing year and the ensuing interactions between environment and age of pasture to be identified. An experiment was commenced in 2015 under sheep grazing in Canterbury and in 2016 under cattle grazing in Waikato, where eight cultivars of perennial ryegrass representing different ploidy, flowering date, and cultivar age (release date), and one cultivar each of tall fescue and cocksfoot were sown in four randomised complete blocks in autumn each year. This paper reports interim data on spring and autumn pasture yield, composition, and density of 3-year-old, 2-year-old and 1-year-old pastures exposed to the same environmental conditions within the same, single year. There were significant effects on yield, botanical composition, basal cover and tiller density due to cultivar, pasture age, and their interaction. When the confounding effect of year-to-year variation was removed by comparing each age cohort in the same year, the underlying differences among grass species and cultivars, and ages of pasture, is starting to reveal the nature of this influence on pasture persistence.


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