Shade avoidance in Trifolium repens: costs and benefits of plasticity in petiole length and leaf size

SummaryThe expression of symptoms of stem nematode reproduction on a total of 53 white clovers (26 cultivars, 14 genepools and 13 introductions from plant collections) was studied in a series of field and glasshouse experiments. Seedlings or stolon-tip cuttings were inoculated with nematodes and the clovers classified by the proportion of plants which developed symptoms. Significant differences were found between varieties although in each test the majority was intermediate between more resistant and susceptible extremes. There was significant positive correlation between tests, in spite of different inoculation methods and different average levels of susceptibility. Very large-leaved cv. Aran was more resistant than most other clovers tested, and small-leaved cv. S. 184 was more susceptible. There was no general correlation of leaf size with reaction to stemnematode. Small-leaved cv. Pronitro was also resistant while several large-leaved cultivars were susceptible. In observations of plants exposed to nematodes over a long period, either by sequential inoculations or through perpetuating latent infections, apparently resistant plants eventually succumbed and supported nematode reproduction. It has not been determined whether this was because selection for virulence in the nematodes had occurred.

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Heritability of frost tolerance in white clover (Trifolium repens)

The Journal of Agricultural Science ◽

10.1017/s0021859600072130 ◽

1990 ◽

Vol 114 (2) ◽

pp. 151-155 ◽

Cited By ~ 5

Author(s):

J. R. Caradus ◽

A. C. Mackay ◽

J. Van Den Bosch ◽

S. Wewala ◽

D. H. Greer

Keyword(s):

White Clover ◽

Trifolium Repens ◽

Size Effects ◽

Leaf Size ◽

Frost Damage ◽

Frost Tolerance ◽

Method Of Calculation ◽

Selection For ◽

Heritability Estimates ◽

High Selection

SUMMARYWhite clover genotypes selected for frost tolerance and susceptibility were pair-crossed in various combinations with unselected genotypes of Grasslands Huia. Progeny lines and parent genotypes were artificially frosted at −8°C and scored for percentage of leaves damaged. Progeny from crosses between frost-tolerant genotypes were less damaged by frost than progeny from crosses involving either susceptible genotypes or unselected Grasslands Huia genotypes. Heritability estimates for frost tolerance or susceptibility were high, ranging from 0·75 to 0·93, depending on method of calculation. Removal of leaf-size effects from scores of frost damage reduced heritability estimates to 0·54–0·73. It was concluded that, because heritability for frost tolerance was high, selection for this character and incorporation of frost tolerance into agronomically suitable but frost-sensitive cultivars by breeding would be successful.

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Vertical stratification and effect of petiole and dry leaf size on arthropod feeding guilds in Cecropia pachystachya(Urticaceae)

Brazilian Journal of Biology ◽

10.1590/1519-6984.15213 ◽

2015 ◽

Vol 75 (3) ◽

pp. 517-523 ◽

Cited By ~ 1

Author(s):

SMA Novais ◽

AS Alvarenga ◽

LAD Falcão ◽

FS Neves

Keyword(s):

Structural Complexity ◽

Leaf Size ◽

Vertical Stratification ◽

Feeding Guilds ◽

Insect Herbivores ◽

Climate Variations ◽

Petiole Length ◽

Nesting Sites ◽

Free Feeding ◽

Species Richness And Abundance

AbstractThis study aimed to test for vertical stratification and the effects of dry leaf size on herbivore and predator arthropods and petiole length on insect borers in Cecropia pachystachya. The leaves were sampled in three strata: attached to the plant, suspended on the vegetation and on the ground. We detected vertical stratification only in the guild of predator arthropods associated with dry leaves, with lower richness and abundance in the attached stratum. In addition, larger leaves positively affected the insect herbivore fauna, whereas the richness and abundance of insect borers increased with petiole length. The greater isolation of leaves attached to trees relative to the surrounding vegetation likely creates greater difficulty for dispersal and colonization by non-winged predators such as spiders. Larger dry leaves provide more shelter against predators and climate variations for insect herbivores. Moreover, larger petioles increase the availability of resources and nesting sites for insect borers. These results are consistent with other studies that found a similarity in the structure of feeding guilds across vertical strata and with studies that showed an increase in species richness and abundance of free-feeding insect herbivores with increasing structural complexity of their host.

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Integration among ramets of Trifolium repens

Canadian Journal of Botany ◽

10.1139/b91-032 ◽

1991 ◽

Vol 69 (1) ◽

pp. 226-228 ◽

Cited By ~ 11

Author(s):

Roy Turkington ◽

Elena Klein

Keyword(s):

Key Words ◽

Trifolium Repens ◽

Leaf Size ◽

Dry Weight ◽

Leaf Number ◽

Subsequent Growth ◽

Shoot Dry Weight ◽

Neighbour Effects ◽

Stolon Length

Cuttings of Trifolium repens were grown in pots without neighbours. When individual interconnected stolons from these cuttings were directed into adjacent pots so that daughter ramets were growing with different grass neighbours, these neighbouring grasses had dissimilar effects on leaf number, leaf size, percent branching of nodes, stolon length, and shoot dry weight. When the T. repens cuttings were grown in pots with neighbours, the effects of different grass neighbours on subsequent growth of stolons and ramets evened out. Key words: integration, clone, ramet, neighbour effects, Trifolium repens.

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The island rule and its application to multiple plant traits

10.26686/wgtn.17136800 ◽

2021 ◽

Author(s):

◽

Annemieke Hendriks

Keyword(s):

Plant Traits ◽

Leaf Size ◽

Small Islands ◽

Small Species ◽

Island Rule ◽

Petiole Length ◽

Island Endemics ◽

Species Pairs ◽

Size Diversity ◽

Plant Stature

<p>The Island Rule refers to a continuum of body size changes where large mainland species evolve to become smaller and small species evolve to become larger on islands. Previous work focuses almost solely on animals, with virtually no previous tests of its predictions on plants. I tested for (1) reduced floral size diversity on islands, a logical corollary of the island rule and (2) evidence of the Island Rule in plant stature, leaf size and petiole length. Endemic island plants originated from small islands surrounding New Zealand; Antipodes, Auckland, Bounty, Campbell, Chatham, Kermadec, Lord Howe, Macquarie, Norfolk, Snares, Stewart and the Three Kings. I compared the morphology of 65 island endemics and their closest ‘mainland’ relative. Species pairs were identified. Differences between archipelagos located at various latitudes were also assessed. Floral sizes were reduced on islands relative to the ‘mainland’, consistent with predictions of the Island Rule. Plant stature, leaf size and petiole length conformed to the Island Rule, with smaller plants increasing in size, and larger plants decreasing in size. Results indicate that the conceptual umbrella of the Island Rule can be expanded to plants, accelerating understanding of how plant traits evolve on isolated islands.</p>

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Sweet Potato Canopy Morphology: Leaf Distribution

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.115.1.39 ◽

1990 ◽

Vol 115 (1) ◽

pp. 39-45 ◽

Cited By ~ 5

Author(s):

Zana C. Somda ◽

Stanley J. Kays

Keyword(s):

Leaf Area ◽

Sweet Potato ◽

Ipomoea Batatas ◽

Plant Density ◽

Leaf Size ◽

Progressive Increase ◽

Leaf Number ◽

Petiole Length ◽

Plant Densities ◽

Leaf Distribution

Changes in leaf distribution of the sweet potato [Ipomoea batatas (L.) Lam.] cultivar Jewel were assessed bi-weekly for 18 weeks at three plant densities (15, 30, and 45 cm × 96-cm spacing). The distribution of leaves on the branches and the timing at which leaf number stabilized were affected by the plant density. Plant density resulted in significant differences in the number of leaves and percentage of missing leaves during the growing season. Leaf number and total leaf area varied substantially in response to plant density, but individual lamina and petiole lengths and leaf area did not vary. Average petiole and leaf lengths and leaf size increased during the season, with the maximum length and area dependent on the type of branch on which the leaf was formed. Average petiole length per branch and the susceptibility to leaf loss increased with descending branch hierarchy (secondary branch < primary branch < main stem). Leaf losses after the 4th week tended to parallel a progressive increase in petiole length of new leaves, suggesting shading as a primary cause of leaf shedding and the loss of the oldest leaves first.

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Yield and stolon characteristics of white clover (Trifolium repens L.) cultivars in perennial pasture in Victoria

Australian Journal of Experimental Agriculture ◽

10.1071/ea96069 ◽

1997 ◽

Vol 37 (2) ◽

pp. 159 ◽

Cited By ~ 3

Author(s):

S. G. Clark ◽

M. J. McFadden

Keyword(s):

White Clover ◽

Trifolium Repens ◽

Leaf Size ◽

Summer Drought ◽

Sheep Grazing ◽

Drought Period ◽

Diverse Range ◽

Herbage Yield ◽

Seed Reserves ◽

Trifolium Repens L

Summary. The herbage yield, stolon characteristics and soil seed reserves of a diverse range of white clover (Trifolium repens L.) cultivars were studied at Hamilton in south-western Victoria. The cultivars were sown with perennial grass (Phalaris aquatica L.) and the pasture was rotationally grazed by sheep. The aim of the study was to identify white clover types which would persist under sheep grazing. The widely used cultivar, Haifa, fails to persist in this environment. Cultivars were divided into 3 groups depending on leaf size (range 2.5–13.0 cm2). Large-leaved cultivars were the most productive in the first year of the experiment but by year 3 some of the intermediate leaf-size cultivars were the most productive. Haifa (large leaved) was particularly unproductive in the third year compared with other large and intermediate leaf-size cultivars. Stolon characteristics were measured in early spring 1987, mid summer 1988 and early autumn 1988. Total stolon yield on each occasion was 0.46–0.99, 0.65–1.68 and 0.05–0.25 t DM/ha respectively. Intermediate leaf- size cultivars tended to have the highest stolon yields on each occasion. Stolon yield declined at the same rate (mean 87%; range 81–92%) in all cultivars between the second and third sampling date indicating that there is no variation in the cultivars’ ability to survive the summer drought period. Although seed reserves for most cultivars were high at the end of the experiment (range 11–130 kg/ha) no seedling recruitment was observed and seed is thought to play no role in sward survival in this environment. Plant breeders developing white clover cultivars for this environment should concentrate on maximising stolon yield at the beginning and end of the summer drought period (January–mid March). Intermediate leaf-size genotypes are likely to provide the best combination of stolon and herbage yield. Grazing management should also aim to maximise stolon yield at these critical times. The use of large-leaved, non-stoloniferous cultivars should be discouraged by advisers as they are not suited to this marginal environment under sheep grazing.

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Characteristics of naturalized populations of white clover (Trifolium repens) in Atlantic Canada

Canadian Journal of Botany ◽

10.1139/b89-293 ◽

1989 ◽

Vol 67 (8) ◽

pp. 2297-2301 ◽

Cited By ~ 3

Author(s):

Joanna Fraser

Keyword(s):

White Clover ◽

Trifolium Repens ◽

Prince Edward Island ◽

Leaf Size ◽

Atlantic Canada ◽

Length Width ◽

Trifolium Repens L ◽

Native Pastures ◽

Agronomic Features ◽

Vegetative Characters

Some characteristics of seven populations of naturalized white clover (Trifolium repens L.) from native pastures in Nova Scotia, Prince Edward Island, and New Brunswick were investigated. Nine vegetative characters were measured on 16- to 18-week-old plants, and within and between population differences determined for cyanogenesis. Variation was observed between and within populations for all measured characteristics. Leaf marks were predominately the central V-shaped chevron; one population had plants without the chevron. Relative leaf size (length × width) ranged from 145 to 784 mm2. Hydrogen cyanide concentrations in leaf laminae were lower in cyanogenic (AcLi) and glucosidic (Acli) genotypes than enzymatic (acLi) genotypes. HCN concentrations in genotypes varied between and within populations. A population from Charlottetown, Prince Edward Island, had several desirable agronomic features, e.g., larger leaves, longer petioles, and thicker stolons than other populations, and could be used in a breeding programme for improved winter-hardy white clover varieties suited for rotational grazing and silage in Atlantic Canada.

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Variation in waterlogging response among ecotypes of Trifolium subterraneum ssp. yanninicum and their relationships with site of origin

10.21203/rs.3.rs-896192/v1 ◽

2021 ◽

Author(s):

Gereltsetseg Enkhbat ◽

Megan H. Ryan ◽

Phillip G. H. Nichols ◽

Kevin J. Foster ◽

Yoshiaki Inukai ◽

...

Keyword(s):

Leaf Size ◽

Trifolium Subterraneum ◽

Dry Weight ◽

Phenotypic Traits ◽

Petiole Length ◽

Waterlogging Tolerance ◽

Seedling Traits ◽

Shoot Dry Weight ◽

Summer Temperatures ◽

Length Reduction

Abstract Background and AimsIn the annual pasture legume Trifolium subterraneum, ssp. yanninicum exhibits higher waterlogging tolerance than ssp. brachycalycinum and ssp. subterraneum. This study investigates waterlogging tolerance within ssp. yanninicum ecotypes and explores correlations with seedling phenotypic traits and site of origin eco-geographic variables.MethodsTwenty eight diverse ssp. yanninicum ecotypes collected from the Mediterranean region and four cultivars were grown in a controlled environment glasshouse. After 14 days of growth seedling traits were measured. After 21 days of growth, free-drained (control) and waterlogged treatments were imposed for 28 days. Eco-geographic variables were generated from ‘WorldClim’ using collection site locations.ResultsUnder waterlogging, shoot relative growth rate (RGR) ranged from 87–108% and root RGR ranged from 80–116% of controls. Waterlogging reduced shoot dry weight (DW) in four of 32 genotypes, while root DW was reduced in 13 genotypes. Leaf size was maintained, or even increased, under waterlogging in 31 genotypes. However, petiole length was more affected by waterlogging and has value as a waterlogging tolerance indicator. Waterlogging tolerance was not significantly correlated with seedling DW, flowering time or precipitation at the site of origin, while shoot growth under waterlogging had a positive correlation with summer temperatures at origin.ConclusionsGenotypes of ssp. yanninicum tolerated transient waterlogging and greater tolerance was observed among ecotypes, rather than cultivars. An easy-to-measure indicator of tolerance was found in petiole length reduction. This study highlights untapped genotypic variability for breeders to improve the productivity and persistence of ssp. yanninicum under waterlogging.

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Trends in the global marketing of white clover cultivars

NZGA: Research and Practice Series ◽

10.33584/rps.6.1995.3374 ◽

1996 ◽

Vol 6 ◽

pp. 7-14

Author(s):

R.D.J. Mather ◽

D.T. Melhuish ◽

M. Herlihy

Keyword(s):

New Zealand ◽

South America ◽

White Clover ◽

Trifolium Repens ◽

Western Europe ◽

Leaf Size ◽

Global Market ◽

Production Region ◽

Trifolium Repens L ◽

Clover Seed

White clover (Trifolium repens L.) is the dominant legume of temperate pastures, having been improved by breeding since the 1930s. The 1994 OECD Register lists 93 cultivars, with a further 25-30 cultivars also known to commerce. Therefore, in excess of 100 cultivars are available to fulfil a world annual market of 8500-10,500 MT. Globally, New Zealand is the major white clover production region, providing 50- 55% of the seed. Other key production regions are Denmark, USA and South America. Consumption of white clover has been relatively static for some time, ranging from 8000-10,000 MT per annum. Between 55-60% of the seed is used in the northern hemisphere (approx. 40% by Western Europe - UK, France, Germany). USA, South America and New Zealand all consume similar tonnages annually (approx. 1000-2000 MT each) with smaller tonnages used in Australia. One cultivar, Grasslands Huia, has dominated the world white clover seed market for many years and it still remains the world's major cultivar by volume. However, in the last 10 years its position has come under increasing pressure from New Zealand and international proprietary cultivars. Eventually proprietary cultivars with improved agronomic performance will supersede the consumption of commodity/public white clovers in those countries where national listing is required to obtain release and recommended listing is need to ensure successful marketing. Despite this, Grasslands Huia will continue for many years to play a major role in supplying markets where national listing is not a prerequisite to release and price is a major factor in purchase decisions. Keywords: commodity cultivar, global market, Grasslands Huia, leaf size, market share, production trends, proprietary cultivar, seed industry, Trifolium repens L., white clover

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