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Defects in achieving a fully differentiated state and aberrant expression of genes and microRNAs (miRs) involved in differentiation are common to virtually all tumor types. Here, we demonstrate that the zinc finger transcription factor ZNF281/Zfp281 is down‐regulated during epithelial, muscle, and granulocytic differentiation in vitro. The expression of this gene is absent in terminally differentiated human tissues, in contrast to the elevated expression in proliferating/differentiating ones. Analysis of the 3'UTR of ZNF281/Zfp281 revealed the presence of numerous previously undescribed miR binding sites that were proved to be functional for miR‐mediated post‐transcriptional regulation. Many of these miRs are involved in differentiation pathways of distinct cell lineages. Of interest, ZNF281/Zfp281 is able to inhibit muscle differentiation promoted by miR‐1, of which ZNF281/Zfp281 is a direct target. These data suggest that down‐regulation of ZNF281/Zfp281 during differentiation in various cell types may occur through specific miRs whose expression is tissue‐restricted. In addition, we found that in rhabdomyosarcoma and leiomyosarcoma tumors, the expression of ZNF281/Zfp281 is significantly higher compared with normal counterparts. We extended our analysis to other human soft tissue sarcomas, in which the expression of ZNF281 is associated with a worse prognosis. In summary, we highlight here a new role of ZNF281/Zfp281 in counteracting muscle differentiation; its down‐regulation is at least in part mediated by miR‐1. The elevated expression of ZNF281/Zfp281 in soft tissue sarcomas warrants further analysis for its possible exploitation as a prognostic marker in this class of tumors. [ABSTRACT FROM AUTHOR]

Squamous cell carcinoma (SCC) is a treatment‐refractory tumour which arises from the epithelium of diverse anatomical sites such as oesophagus, head and neck, lung and skin. Accumulating evidence has revealed a number of genomic, clinical and molecular features commonly observed in SCC of distinct origins. Some of these genetic events culminate in fostering the activity of ΔNp63, a potent oncogene which exerts its pro‐tumourigenic effects by regulating specific transcriptional programmes to sustain malignant cell proliferation and survival. In this review, we will describe the genetic and epigenetic determinants underlying ΔNp63 oncogenic activities in SCC, and discuss some relevant transcriptional effectors of ΔNp63, emphasizing their impact in modulating the crosstalk between tumour cells and tumour microenvironment (TME). [ABSTRACT FROM AUTHOR]

Breeding for enhanced quality in lucerne ( Medicago sativa) frequently involves selection for higher leaf-to-stem ratio, multifoliolate leaves or short-internode stems. Three populations selected for such alternative morphologies and a reference cultivar were evaluated for forage yield, leaf-to-stem ratio and protein and fibre concentrations in leaves, stems and whole plants. Four managed environments were obtained by combining two stress levels (moderate or nil) with two sowing times. The population selected for high leaf-to-stem ratio, as well as the short-internode population, had highest leaf-to-stem ratio (1.27) across six harvests in two non-stress environments. The latter population had higher stem protein (12.9%) and lower stem neutral-detergent fibre ( NDF) concentration (58.7%) than other populations. The multifoliolate population had intermediate quality, showing low expression of the multifoliolate trait (14.0% across four environments), particularly under stress (10.5%). The autumn-sown, fully irrigated environment had, on average, highest dry-matter yield (4.19 t ha−1) and lowest leaf-to-stem ratio (0.74). Drought-stressed environments had lower plant NDF (−12.3% on average) and leaf protein (−9.7%), and higher stem protein (+8.6%) than fully irrigated environments. The results suggested that environmental effects might have greater impact on quality than genetic effects, even for a population set including material selected for quality-driven morphology. [ABSTRACT FROM AUTHOR]

Adaptation to severe drought and to irrigated cropping can both contribute to increased water use efficiency of lucerne, but knowledge on the relevant adaptive traits is limited. Five cultivars featuring contrasting adaptive responses for 3-year forage yield across 10 agricultural environments of the western Mediterranean basin were currently studied, to identify physiological and morphological traits associated with specific and wide-adaptation responses. The landraces Mamuntanas, Demnat 203 and Erfoud 1, and the varieties SARDI 10 and Prosementi, were grown in replicated metal containers (55 cm long × 12 cm wide × 75 cm deep; 21 plants per container) under irrigation (weekly restoring soil field capacity) and under moderate and severe drought stress (implying decreased irrigation for 30 days followed by withheld irrigation for 33 and 58 days, respectively). Cultivar post-stress survival reflected the known cultivar adaptation to drought-prone agricultural environments. Demnat 203, specifically adapted to irrigated, frequently mown environments, displayed higher amounts of starch, soluble proteins and total nitrogen in the crown and the root under irrigation. This was due to outstanding organ size and, for starch, higher concentrations. Mamuntanas, specifically adapted to drought-prone environments, exhibited high water-soluble carbohydrate concentration in storage organs under severe stress, along with a water-conservation strategy implying less water used in initial drought-stress phases due to limited early root development that resulted in more water available under severe stress. Drought-tolerant germplasm also displayed lower wilting under early stress, more plants with green tissues under severe stress, and more stems per plant in stress or favourable conditions. Multivariate patterns of cultivar variation for physiological and morphological traits were strictly associated with cultivar variation for adaptation pattern. Our results highlighted the difficulty to combine some traits of environment-specific adaptive value into a unique widely adapted variety, supporting the selection of varieties specifically adapted to irrigated or severely drought-prone environments. [ABSTRACT FROM AUTHOR]

This study aimed to support red clover ( Trifolium pratense L.) breeding programmes by investigating germplasm adaptive variation. Four landraces representative of the former commercial ecotypes from northern and central Italy, thirteen natural populations collected in Italy across a wide latitudinal and altitudinal range in exploited or abandoned old natural grasslands, natural pastures or in the wild, and the varieties Perseo and Divin were evaluated for 2-year forage yield, for plant survival and for some morphophysiological traits. Evaluations were made at two sites, one with a subcontinental climate ( Lodi) and the other with a Mediterranean climate ( Viterbo). Specific adaptation was particularly large in natural populations, whose interaction with location implied a widespread inversion of population ranks across sites for forage yield depending on their geographical origin. Forage yield and persistence of the populations were not correlated, owing to the trend of landrace and variety germplasm towards high yield but poor persistence. At Lodi, forage yield was associated with winter hardiness and was maximized by landrace germplasm, whereas persistence depended on various factors and was high only in a set of natural populations collected from pastures. At Viterbo, natural populations that evolved under severe summer drought stress tended towards high yield and persistence, showing no yield disadvantage relative to the best-performing landrace or variety germplasm. [ABSTRACT FROM AUTHOR]

Extensive livestock is a basic socio-economic feature of the Mediterranean region whose environmental and economic sustainability depends on the ability of forage resources to withstand climatically stressful conditions. Perennial forages such as tall fescue can be a valuable alternative to annuals, if they can survive across successive summer droughts. Three-year dry matter yield and plant survival of five cultivars of Mediterranean-type tall fescue were evaluated in six sites of Algeria, France, Italy, Morocco and Portugal, with the following objectives: (i) modelling adaptive responses and targeting cultivars as a function of environmental factors associated with genotype × location interaction; and (ii) defining plant ideotypes, adaptation strategies and opportunities for international co-operation for regional breeding programmes. Site mean yield and winter temperatures were positively correlated, whereas sward persistence was positively correlated to lower site heat and drought stress. Cultivar adaptation was adequately modelled by factorial regression as a function of site spring-summer (April-September) drought stress (long-term potential evapotranspiration minus actual water available) for yield, and annual drought stress for final persistence. Specific-adaptation responses to high- or low-stress environments emerged which were consistent with drought-stress levels of cultivar selection environments. However, the wide-adaptation response of cultivar Flecha suggested that breeding for wide adaptation can be feasible. [ABSTRACT FROM AUTHOR]

White clover-grass mixtures should provide swards with a high dry matter (DM) yield with a clover proportion of at least 0·30. This study assessed the compatibility of one white clover variety selected for competitive ability (Giga) and four other large-leaved clover varieties (Aran, Espanso, Fantastico and Regal) in mown binary mixtures with each of four grass companions (cocksfoot cv. Padania, hybrid ryegrass cv. AberExcel, Italian ryegrass cv. Crema, and tall fescue cv. Magno) over 3 years in northern Italy. On average, the mixtures including Giga had at least a two-fold greater clover proportion in the total harvested DM ( P < 0·01) and contained fewer weeds ( P < 0·10) than those with other clover varieties, and also tended to have the highest total DM yields. On average, mixtures containing AberExcel had clover proportions of >0·25 but gave the lowest total DM yields, whereas those of Magno maximized total DM and had a higher proportion of clover than Padania or Crema. No clover × grass interaction was detected ( P > 0·05). The association with Giga allowed the tall fescue-based mixture to attain a clover proportion 0·331 along with a top-yielding total DM. This mixture, compared with the only one without Giga that displayed a near-sufficient clover proportion (Espanso with AberExcel), exhibited a 21·7% higher total DM ( P < 0·05) and had far fewer weeds. [ABSTRACT FROM AUTHOR]

Mixed swards of white clover–grass mixtures in highly productive environments often fail to reach the minimum recommended annual clover proportion of about 0·30. This study assessed the effect on clover content and total dry matter (DM) yield of two spring N applications (0 and 45 kg N ha−1) and two distances between drilled grass-rows (0·18 and 0·36 m) over 3 years for mown swards of white clover–Italian ryegrass ( Trifolium repens–Lolium multiflorum) in binary mixtures in northern Italy. An additional aim was to determine the advantage of association of grass–clover compared with grass and clover monocultures. On average, N fertilization of mixtures resulted in almost 9% higher total yield ( P < 0·01; mean response = 18·1 kg of total DM per kg of N) but decreased the clover proportion (0·250 vs. 0·312). Wider grass-row spacing increased clover proportion (0·327 vs. 0·234; P < 0·01) with no reduction of total DM yield. N fertilization × grass-row spacing interaction occurred only for clover content ( P < 0·01). Without N fertilization, mixtures out-yielded clover and grass pure stands. With N fertilization, at double rate to pure grass, yields from mixtures were greater than from clover and comparable to Italian ryegrass. [ABSTRACT FROM AUTHOR]

Understanding of adaptation targets, selection environments, genetic resources, and plant types is required in breeding tall fescue [Lolium arundinaceum (Schreb.) S.J. Darbysh.] and orchardgrass (Dactylis glomerata L.) for Mediterranean environments prone to drought stress. Fourth-year forage yield of seven orchardgrass and five fescue cultivars grown in Algeria and Sardinia revealed (i) crossover cultivar × location interaction in orchardgrass, with dormant germplasm performing best in the drier Algerian site, and nondormant Mediterranean material performing best in Sardinia; and (ii) the advantage of tall fescue over orchardgrass in both sites. Yield of Algerian populations of orchardgrass and tall fescue grown in Algeria was generally lower than the best control ('Flecha' tall fescue). Other studies in Italy showed (i) the possibility to select orchardgrass from Mediterranean germplasm that combines summer survival under moderate stress with response to summer rain events; (ii) the nil effect in a Mediterranean site, and the slightly positive effect in a subcontinental climate site of endophyte infection on tall fescue survival; and (iii) the adaptation of Mediterranean and Continental fescue germplasm to their respective climatic areas. [ABSTRACT FROM AUTHOR]

Breeding for specific or wide adaptation would be more cost-efficient if preliminary indications on genotype adaptive responses could be provided by easily-detectable morphophysiological or molecular characteristics. We investigated the consistency among adaptation parameters, morphophysiological traits and SSR markers in estimating and structuring the genetic diversity among 24 durum wheat genotypes. Additive main effects and multiplicative interaction adaptation parameters were estimated across 14 Algerian locations belonging to a low- or a high-elevation subregion. Eight morphophysiological traits were assessed in two locations per subregion. Genotype Euclidean distances based on adaptation parameters were closely related to those based on morphophysiological traits ( r = 0.75, P = 0.01). Marker-based distances exhibited low correlation with those based on adaptation parameters ( r = 0.26, P = 0.01) or morphophysiological traits ( r = 0.32). The consistency between adaptation parameters and morphophysiological traits for genotype ordination and classification was greater than that between either information layer and SSR markers. Optima of phenology and plant height differed between subregions, whereas many kernels per spike and fertile tillers were associated with adaptation to both subregions. [ABSTRACT FROM AUTHOR]

Efficient crop growth with low nitrogen (N) application is becoming a requirement to face the concern on excessive N emission to the environment and the increasing cost of fertilizers. This study compared six natural populations and three improved varieties of tall fescue ( Festuca arundinacea Schreb.) for dry-matter yield over 4 years under ordinary N fertilization (450 kg ha−1 in the 4 years) and very low N fertilization (only 40 kg ha−1 prior to sowing). Both endophyte-infected (EI) and endophyte-free (EF) forms of each accession were sown. On average, ordinary fertilization implied 30 % higher yield than very low fertilization and the EI germplasm outyielded the corresponding EF germplasm (+4.4 %). Mean yield of improved varieties was higher than that of natural populations under ordinary fertilization (P < 0.05), whereas the two germplasm groups did not differ under very low fertilization. Accession × N fertilization interaction was found among natural populations but not among varieties (P < 0.05). A few natural populations were top-yielding under very low fertilization and may be exploited, possibly in combination with endophyte infection, to select tall fescue varieties with enhanced performance under limited N application. [ABSTRACT FROM AUTHOR]

Seed yield is of crucial importance for the marketing of lucerne varieties. Statistical records for farmers’ production of certified seed suggested a slightly higher seed-yielding ability of Italian landraces over improved varieties (proportionately 0·052). The aims were to: (i) assess the variation among landraces, and compare the germplasm of landrace and improved varieties, for seed-yielding ability; and (ii) investigate the relationships between seed yield, environment of origin and forage yield of the landraces. Thirteen farm landraces belonging to the seven commercial ecotypes of northern Italy and four improved varieties were evaluated for seed yield in the third cropping year and for herbage yield over twelve harvests. Landraces differed in seed yield and herbage yield ( P < 0·05). Landrace material, compared with variety germplasm, showed a non-significant trend towards higher seed yield (proportionately 0·047) and had similar herbage yield and plant density at the onset of the third cropping year. Seed yield of landraces was unrelated to forage yield and was associated with frequent mowing and earlier year of seed production on its farm of origin. [ABSTRACT FROM AUTHOR]

A comparison was made of landrace vs. variety inter- and intra-population genetic variation for leaf:stem ratio in lucerne and investigated its relationship with forage yield and other characters. Very early-flowering genotypes were excluded from the assessment to limit the impact of maturity stage on the variation in leaf:stem ratio. The evaluation was performed on a summer harvest of 390 genotypes belonging to ten landraces from northern Italy and to six well-performing varieties, and on nineteen clones of a single genotype which were used to estimate the environmental variance. Landrace and variety groups did not differ in mean leaf:stem ratio. Variation for this trait was significant among varieties ( P < 0·05) but not among landraces. Within-population variation was significant for both germplasm groups ( P < 0·01), being somewhat larger in landraces. The estimated within-population variance component largely exceeded the among-population variance component within varieties. Higher leaf:stem ratios were mainly associated with shorter and thinner main stems in genotypes and populations, and showed a modest inverse correlation with forage yield. The results highlight the importance of landrace germplasm and the paramount importance of selection within populations to identify parent material with a high leaf:stem ratio. [ABSTRACT FROM AUTHOR]

Turf quality is a complex character of fundamental importance in turfgrass evaluation. It takes into account aesthetic and functional aspects, and depends on several individual components which may vary with time. The use of a synthetic and simple quality score is necessary when evaluating large numbers of varieties. The quality of 110 turfgrass varieties belonging to four species ( Lolium perenne, Poa pratensis, Festuca arundinacea and F. rubra) was assessed in the second and third years of growth at three Italian locations, i.e. Lodi (Po Valley, continental climate), Perugia (central Italy, sub-Mediterranean climate) and Foggia (southern Italy, Mediterranean climate), using a visual score ranging from 9 (outstanding turf) to 1 (very poor turf). A randomized block design with three replicates was used, with varieties of the same species being blocked to facilitate the comparison within species. On average, F. rubra had the lowest turf quality score in summer, whereas the other species had the lowest quality score in winter and the highest quality score in summer and autumn. Components of variance were large for genotype (i.e. variety) main effects in all species. A variety × location interaction was found in F. arundinacea and higher-order interactions were also found for P. pratensis and F. rubra. Genotype × environment effects were small relative to genotypic effects in L. perenne. Variety × year interactions were small in all cases, whereas variety × location and variety × season interactions were greater. Stability of turf quality across sites, seasons and years was measured for each variety in terms of environmental variance, i.e. the variance of score values across sites, years and seasons. Mean scores and stability values of varieties were integrated into an index of reliability that estimated the lowest score value expected in 0·80 of cases. For each species, a small subset of highly reliable varieties could be identified. Implications of the results for the testing and breeding of varieties in Italy are discussed. [ABSTRACT FROM AUTHOR]

The study aimed at: i) assessing the agronomic value of the pure stand (PS), of the complex mixture (CM) and of the binary mixture with each of six white clover genotypes (MWC) of eight grass varieties belonging to four species and contrasting for earliness of flowering; and ii) investigating the relationships of competitive abilities in CM and MWC with some morpho-physiological traits of the grass varieties. CM showed a 24% dry matter yield (DMY) advantage over mean value of PS but did not outyield the pure stand of the best yielding component. For grass-white clover associations, the DMY advantage as Relative Yield Total over PS of the components averaged 43%. DMY of the grass varieties averaged across MWC conditions was related positively to total DMY (r = 0.99) and negatively to associated clover DMY (r = -0.96). Competitive abilities as Relative Yield of the grass varieties in CM and in MWC correlated (r = 0.84) and were both positively associated to DMY, canopy height and inclination of leaves in PS. The results suggested that association of white clover with a grass of moderately high vigour, intermediate earliness and relatively erect leaves may provide the best option for rotational meadows in the experiment environment. [ABSTRACT FROM AUTHOR]

Eighteen common-wheat varieties grown for three seasons at 31 locations in Italy were used to study the relationships between cultivar adaptation patterns, climatic factors and morphophysiological traits of genotypes, as well as defining macro-environments for the selection and recommendation of genotypes in the region. The variances of both the genotype and genotype-season interactions were significant, the former being almost 80 % greater than the latter. Some 10.4 % of genotype-location interaction was accounted for by heterogeneity of genotype regressions on site mean, 38.0 % by the first two axes of a principal components analysis and 32.0 % by definition of four macro-environments. Occurrence of genotype-location interaction was related to the level of late frosts, winter cold, and late drought and heat stress at each location, and to heading date and tolerance of frost, Septoria blotch and lodging in each genotype. Following estimates of broad-sense heritability, breeding for specific adaptation may be envisaged for northern and central Italy on the one hand and southern Italy on the other. Morphophysiological traits contributing to better performance in each of these macro-environments were indicated. [ABSTRACT FROM AUTHOR]

Twenty-two durum wheat landraces of various origins were evaluated for performance and stability of grain yield, protein content and gluten strength (SDS sedimentation volume) at two sites of Northern Syria situated in the drought-prone part of the local durum wheat belt. Yield was recorded in three seasons, while protein content and SDS volume were assessed in two seasons only. A high "entry × environment" interaction was observed for all traits, which was significantly attributable to heterogeneity of entry regressions on the environmental mean for grain yield only. Compared to the recently-bred widely-grown variety 'Sham 1', some landraces showed somewhat similar yield responses , whereas other proved more stable without being significantly lower yielding. Significant variation was found for SDS volume, through only few of the best-ranking landraces for this trait also possessed an acceptable yield level. The entries did not significantly differ for protein content. The board sense heritability estimates obtained for grain yield (0.59) and SDS volume (0.89) highlighted the interest in some of the landraces examined for improving grain yield and quality in the region. [ABSTRACT FROM AUTHOR]

A set of 20 accessions of durum wheat (Triticum turgidum L., durum group), which mostly included exotic landraces from various Mediterranean countries, and four Italian improved varieties were evaluated for grain yield in five environments and for quality traits in two environments of Sicily. Glutenin composition was also assessed electrophoretically on six seeds per entry. The cultivars differed (P &les; 0.01) for yield, protein content and sodium dodecyl sulphate (SDS-sed) sedimentation volume, in the presence of significant (P &les; 0.001) genotype-environment interaction effects. These effects were large for yield and moderately large for protein content relative to genotype main effects following estimation of variance components. Most exotic cultivars yielded comparably with, and some of them showed greater stability than, the best yielding Italian variety 'Simeto'. Some exotic cultivars combined outstanding yield, protein content and SDS-sedimentation values and represent therefore extremely valuable germplasm sources to broaden the local genetic base. The glutenin composition LMW-2 and HMW 7 + 8 was positively associated with gluten quality. Six entries showed heterogeneous electrophoretic patterns, suggesting the presence of different genotypes within the cultivar. [ABSTRACT FROM AUTHOR]

The genetic control of tall fescue forage yield has been poorly investigated. Full-sib families from diallel crosses of Mediterranean germplasm were evaluated for forage yield over 34 months in a Mediterranean environment with severe drought stress (diallel 1, with 20 parents) and over 16 months under irrigation in a heated greenhouse simulating the Mediterranean temperature pattern (diallel 2, with 15 parents). Genetic parameters were estimated for fresh biomass in diallel 1 and dry-matter yield in diallel 2. Additive genetic variance was always larger than non-additive (dominance) variance. Narrow-sense heritability was fairly high ( h2 = 0.61) in diallel 1 and moderate ( h2 = 0.45) in diallel 2. Predicted yield gains from one selection cycle were larger in the former diallel (23.9%) than in the latter (10.5%), suggesting that gains can be enhanced by selection under severe drought stress and over a time span sufficient to allow the variation in persistence to fully emerge. General combining ability effects of eight parents that were common to both diallel crosses were highly correlated ( r = 0.94) across the contrasting evaluation environments. The extent and consistency of additive genetic effects across environments suggest that rapid improvement of forage yield is possible. [ABSTRACT FROM AUTHOR]

Phenotypic selection under spaced planting is frequently used in forage species. This study aimed to compare the predicted efficiency of direct selection for lucerne seed or forage yield under dense planting with indirect selection based on the same traits or seed yield components evaluated under spaced planting. Sixteen genotypes randomly chosen from a representative sample of locally adapted germplasm were grown for two years as individual clones spaced at 75 cm (density =1.78 plants/m2) and in dense plots formed by one row of four clones spaced at 10 cm (density = 50 plants/m2) using a randomized complete block design with three replications. Indirect selection based on seed yield under spaced planting was just 19% less efficient than direct selection, owing to moderate genetic correlation between plant densities ( rg = 0.66) and somewhat higher broad-sense heritability under spaced planting than under dense planting. The relative efficiency of indirect selection for seed yield in density based on individual seed yield components under spaced planting ranged from modest to very low and was always below 45%. The efficiency of indirect selection for dry matter yield based on yield response under spaced planting was moderate for total yield (64%) and very low for second-year yield (32%) relative to direct selection. [ABSTRACT FROM AUTHOR]

Higher ruminant intake potential andin vivodigestibility as indicated by lower neutral and acid detergent fibre (NDF and ADF), respectively, and higher crude protein (CP), may be valuable targets in tall fescue breeding. Some 105 full-sib families from a diallel cross of Mediterranean parent germplasm were grown in a heated greenhouse simulating the temperature pattern of a Mediterranean environment, to estimate genetic parameters for NDF, ADF, CP and dry matter (DM) yield in one autumn and one winter harvest. Family × harvest interaction was large for NDF and ADF, moderate for CP and absent for DM yield. Additive genetic variance was mostly larger than specific genetic variance, and tended to be small for quality traits and large for DM yield. Narrow-sense heritability was low for CP and ADF in autumn and moderate to fairly high in the remaining cases. Predicted gains per selection cycle never exceeded 5% for quality traits while being greater than 10% for DM yield. An inverse genetic correlation between DM yield and any quality trait emerged in the presence of sizeable genetic variation. [ABSTRACT FROM AUTHOR]

High persistence and seed yield are important targets in white clover breeding but their assessment is expensive. The efficiency of indirect selection for these traits performed on characters recorded during a medium-term dry matter (DM) yield evaluation was verified for large-leaved populations in separate experiments for medium-term (three-year) and long-term (fourth and fifth year) DM yield (Trial 1) and seed yield (Trial 2). The best results were provided by stolon density observed at the end of the third cropping year for prediction of long-term yield, and by the product of number of heads times number of florets per head assessed prior to mowing in Trial 1 for prediction of seed yield in Trial 2. Indirect selection was about as efficient as direct selection in these cases. Predictions of persistence from three-year or third year DM yield, and seed yield from single seed yield components in Trial I were less accurate. [ABSTRACT FROM AUTHOR]

Sixteen white clover genotypes and their half-sib progenies were grown in pure stand. Each clover progeny was also grown in a mixed stand that also included three grass varieties of different species. Dry matter (DM) yield was measured over 2 years and seed yield at the second year. Competitive ability of clover families was defined as the ratio between mixed stand and pure stand for clover DM yield. Narrow-sense heritability from parent–offspring regression of pure stand data was high to moderate (h2 > 0.50) for DM yield, seed yield and most of their components. Persistence as predicted by stolon density showed negative genetic correlations with seed yield (rg = -0.70) and DM yield (rg = -0.60), whereas seed yield and DM yield tended towards a negative correlation (rg = -0.45). Sizes of different vegetative or reproductive organs were generally correlated positively. Evidence was provided that the set of parent genotypes represents well the genetic variation available within the Ladino gene pool. The results highlighted the difficulty of combining relatively short-term DM yield, persistence and seed yield into a unique plant type. Differences in competitive ability emerged only in the second year, better ability being related mainly to petiole length among the traits assessed in pure stand. [ABSTRACT FROM AUTHOR]