Growth Of White Clover Research Articles

Competitiveness and persistence of introduced rhizobia on oversown clover: Influence of strain, inoculation rate and lime pelleting

Five strains of R. trifolii were evaluated, at two inoculation levels in the presence or absence of lime pelleting, for their ability to compete and persist in a tussock grassland soil containing a naturalized population of rhizobia. Effects on the growth of the oversown white clover ( Trifolium repens) were also investigated. Strains showed marked differences in their ability to form nodules on the host in competition with the naturalized population of rhizobia and also differed in their persistence over 15 months. The most competitive and persistent strain was PDDCC 2163 followed by 2153, 2666 and 2668 and the least competitive was 4144. Lime pelleting or increasing the rate of inoculation increased the competitive ability of strains. Strains that were highly competitive increased clover dry matter and N uptake.

Effect of root hair length on white clover growth over a range of soil phosphorus levels

Abstract In an attempt to improve the competitiveness of white clover within swards on low-phosphorus (P) soils, selections were made for plants with long or short root hairs within Trifolium repens L. cv. Tamar. Three populations with significantly different root hair lengths were grown at a range of soil-P levels. Increasing root hair length has a significant effect on plant dry weight because of increased P absorption, if the roots were not mycorrhizal. However, mycorrhiza are ubiquitous in New Zealand pastures and therefore increases in root hair length may not improve white clover performance on low-P soils.

Effects of Three Viruses on Growth of White Clover

Effects of Three Viruses on Growth of White Clover

Use of an (n, ?) nuclear reaction to study the long-distance transport of boron in trifolium repens after foliar application

The growth of white clover (Trifolium repens L.) is severely inhibited by boron starvation, but a foliar treatment with boric acid can transitorily alleviate the deficiency symptoms. The (10)B(n ,α)(7) Li nuclear reaction has been used to study boron transport in the plant after foliar application. More than 98% of the boron supplied remained at the point where it was applied to the leaves, and less than 2% was useful to the growth of the treated plant. This small "efficient" portion of boron was quite mobile. It was distributed to the different parts of the plant, then was transferred from the oldest parts to the newly formed leaves. Physiological and agronomical implications of these data are discussed.

Growth and carbon economy of nodulated white clover in the presence and absence of combined nitrogen

AbstractAn investigation of the carbon economy of single S184 white clover plants nodulated with an effective strain of Rhizobium trifolii growing on N‐free nutrient solution and supplied with 150 parts/106 N as NH4NO3 has shown that 10% more of the C fixed per day is available for growth in the plants supplied with combined N. The difference between the two groups of plants is a result of higher respiratory activity in the roots of plants growing exclusively on N2. In terms of shoot growth, however, the difference in growth rate is likely to be less than 10%, because the rate of root growth is greater in the plants supplied with a moderate level of combined N. There is no evidence that NO‐3 and CO2 compete for photosynthetically produced reductant in the leaves of plants grown on N2+NH4NO3, since no reduction in net photosynthesis was observed in plants assimilating combined N.An experiment carried out on detached leaflets of white clover grown on N2 and on N2+ NH4NO3 has shown that NO‐3 ‐reducing activity is present in the leaflets of plants grown on N2+ NH4NO3 but not in plants grown on N2 and that the activity is light‐dependent. Measurements of 14CO2 respired in the light and dark by leaflets previously allowed to photosynthesize 14CO2 showed that the ratio of 14CO2 output in the light to 14CO2 output in the dark was no higher in plants grown on N2+ NH4NO3 than in plants grown on N2. This observation is consistent with the finding that N source does not affect net photosynthesis in whole plants.

Establishment and growth of clovers and lotus on acid soils

Abstract Factors affecting the establishment and growth of ‘Grasslands Huia’ white clover (Trifolium repens), ‘Grasslands Pawera’ red clover (T. pratense), and ‘Grasslands Maku’ lotus (Lotus pedunculatus) oversown on an acid, low fertility tussock grassland soil were investigated under mowing conditions. Broadcast lime increased both the establishment and growth of clovers but increased only the establishment of lotus. Lime pelleting markedly increased nodulation of white clover but had no effect on lotus. Increasing the level of P to 60 kg/ha markedly increased the production of lotus but gave only a small increase in white clover growth, a result attributed to soil acidity limiting the white clover response. Once established, legume and total (legume and grass) yields were higher from lotus alone than from white clover alone, a 50:50 lotus:white clover mixture, and a 50:50 white:red clover mixture.

Improved growth of white clover in hill grasslands by mycorrhizal inoculation

SUMMARYField trials in a hill grassland area of mid‐Wales showed that growth of white clover could be improved by inoculation with selected vesicular‐arbuscular (VA) mycorrhizal fungi. After one growing season mycorrhizal inoculation had approximately doubled shoot dry weight, runner number and nodulation at two sites previously improved by adding lime and fertiliser and by replacing the native vegetation mainly with rye‐grass and white clover. At a previously unimproved site, limed at the time of planting, mycorrhizal inoculation increased shoot dry weight by up to two and a half times, almost doubled runner formation, and increased nodulation up to five‐fold where 90 kg P/ha as basic slag had been applied. Responses to mycorrhiza at this site were smaller with 22‐5 kg P/ha as basic slag and were absent where no P was added. After two growing seasons inoculation responses were even more pronounced at this previously unimproved site; where clovers were being overgrown by adjacent native grasses only those given both 90 kg P/ha and mycorrhizal inoculation survived well.

Effect of vesicular-arbuscular mycorrhizas on growth of white clover, lotus, and ryegrass in some eroded soils

Abstract Vesicular-arbuscular mycorrhizal fungi were absent or poorly represented in most of the eroded soils tested. In pot experiments their reintroduction generally increased plant growth. These results are discussed in relation to the re-establishment of vegetation on eroded land

Mycorrhizal Infection in Pennine Grassland. III. Effects of Mycorrhizal Infection on the Growth of White Clover

Mycorrhizal Infection in Pennine Grassland. III. Effects of Mycorrhizal Infection on the Growth of White Clover

Growth of white clover in undisturbed soils after inoculation with efficient mycorrhizal fungi

Abstract Clover seedlings were inoculated with the indigenous or one of three introduced mycorrhizal fungi and transplanted into undisturbed cores of eight hill country soils. After several harvests, at least one of the introduced fungi had increased shoot growth in each soil from between 16 to 117%. In most soils, the growth benefit from inoculating with an introduced mycorrhizal fungus tended to decrease after the initial shoot harvest, and was then maintained at a lower level over subsequent harvests. In a Taihape silt loam, however, the growth benefit from Glomus tenuis inoculation increased steadily over six harvests. In four out of five soils, previous application of phosphate fertiliser (50 kg P/ha/year) did not reduce mycorrhizal growth responses.

Influence ofHeterodera trifoliicyst inoculum on white clover growth and final cyst count in pots of a yellow-brown pumice soil

Influence of<i>Heterodera trifolii</i>cyst inoculum on white clover growth and final cyst count in pots of a yellow-brown pumice soil

Growth and Maintenance Requirements of White Clover as a Function of Daylength1

Carbon dioxide exchange rates of white clover (Trifolium repens L.) stands were monitored for several days at 30 C, a high light level (2.0 mE.s−1.m−2), and different day/night lengths in the range 6/18 to 18/6 hours. The plants were then kept in continuous darkness for 2 days. Thornley's growth and maintenance coefficients were calculated from the 24 hour CO2 exchange rates. The yield of new biomass carbon (C) per unit of C input into growth (Yg) was found to be independent of daylength, the average value being 0.74 ± 0.01. The maintenance loss rate of C per unit of biomass C present (m), increased from 36 to 53 mg.g−1 24hour−1 as the daylength increased from 6 to 18 hours. This was shown to be an indirect effect of the seven‐fold increase in the growth rate (24 hour net gain) from 12 to 90 g Co2.m−3.24hour−1. No direct effect of daylength on either growth or maintenance requirements was found.

Effect of strains of Rhizobium trifolii on the establishment of oversown white clover ( Trifolium repens)

Strains of Rhizobium trifolii incorporated into commercial peat inoculants were compared for their effect on the establishment and growth of oversown white clover ( Trifolium repens) on soils devoid of infective rhizobia. There were marked differences in numbers of seedlings establishing and clover dry matter production per hectare with the various strains. However, when adjusted to a constant number of established seedlings, dry matter production from all strains, apart from one strain at one site, were similar indicating that the strains did not appear to influence the growth of individual clover plants. The marked differences in establishment of clover inoculated with the various strains could not be accounted for by differences in the number of rhizobia in the peat inoculant. Selecting strains of rhizobia for ability to increase establishment is considered important where clover is oversown onto soils devoid of rhizobia.

Mycorrhizas in hill country soils

Abstract Indigenous mycorrhizal fungi quickly infected oversown white clover in Waingaro steepland (hill country) soil throughout the year, except in late winter when the rate was reduced as the soils became waterlogged. Infection rates and growth responses in Dunmore silt loam were determined for three grasses and three legumes infected with the indigenous and two other mycorrhizal fungi and grown in the field and in sterilised soil in the glasshouse. Mycorrhizal infection rates were slower and dependence on infection for growth and P uptake was usually less in Lotus and in grasses than in clovers. Of the fungi tested, Gigaspora margarita was the most efficient at stimulating growth of grasses and white clover, but was less efficient than the indigenous fungi at stimulating red clover growth. Mycorrhizal infection greatly stimulated legume nodulation.

Effect of vesicular-arbuscular mycorrhizas on response of ‘Grasslands Huia’ and ‘Tamar’ white clovers to phosphorus

Abstract Inoculation with vesicular-arbuscular mycorrhizal fungi stimulated the uptake of soil P and enhanced the growth of white clover at low levels of applied P. At high levels of applied P mycorrhizal fungi depressed growth. ‘Tamar’ white clover outyielded ‘Grasslands Huia’, particularly at the high levels of applied P. At the lowest level of applied P Tamar had more of its roots converted to mycorrhizas and was more mycotrophic than Huia. Endomycorrhizas formed by the indigenous fungi may benefit field-grown white clover in Warepa silt loam with applications of up to and possibly in excess of 20 kg P/ha.

Effect of soil aeration on the growth of white clover in a glasshouse pot experiment

Abstract The possibility that growth might be limited when plants are grown in pots without holes in the base was investigated. The growth of white clover in either Wairakei sand or Wharekohe silt loam was measured, in pots with no holes, or 1, 5, or 13 holes. In the Wairakei sand varying the number of holes in the pots had no significant effect on dry matter yield In the Wharekohe soil, there was a gradual increase m total dry matter yields from four harvests with increasing number of holes in the pots; clover yields from pots with 5 or 13 holes were significantly higher than those from pots without holes.

Effects of soil temperature on growth and nutrient content of white clover in a glasshouse pot experiment

Abstract In a glasshouse pot experiment comparing the growth of white clover in aluminium-painted containers and containers evaporatively cooled with moist absorbent paper, the cooled pots showed significant increases in dry matter yields in the latter part of the trial during the summer of 1974–75. There were higher concentrations of mineral nutrients, especially of magnesium, calcium, manganese, zinc, and boron, in herbage grown at higher soil temperatures.

The effects of tungstate and nitrogen source on the dry weight and nitrogen yields, and molybdenum and tungsten content, of white clover (Trifolium repens)

The effect of tungstate on the growth of white clover was investigated in sand cultures in a glasshouse, using three different nitrogen sources; symbiotic nitrogen fixation, nitrate, and ammonium. Each nitrogen treatment solution was subdivided into three groups containing 0, 5 and 50 ppm tungsten as tungstate and the effect on dry weight and nitrogen yields, and molybdenum and tungsten content, was determined for each treatment.

RED CLOVER: A NOTE

AMONG legumes used in pastures red clover has an important role in maintaining pasture production in late summer. whentemperature and soil moisture levels may limit the growth of white clover. Under these conditions red clover is capable of high levels of growth and is one of the most productive pasture species at that time.

Interaction of lime and seed pelleting on the nodulation and growth of white clover

Abstract The effects of inoculation level, seed pelleting, and broadcast lime on the establishment and growth of white clover (Trifolium repens) oversown on an acid (pH 4.8) high country yellow-brown earth were investigated. When inoculated seed was effectively pelleted with lime there was no significant effect of broadcast lime on the percentage of healthy seedlings, percentage cover, or clover dry matter, although there was an increase in the percentage nitrogen in the foliage. In contrast, broadcast lime increased all these parameters in the absence of pelleting.