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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]

Legume-based annual forages could be pivotal for the sustainable intensification of forage production in drought-prone Mediterranean cereal-livestock systems. This study aimed to optimise the composition of these crops for three climatically contrasting areas. Four legumes (field pea of semi-dwarf and tall type; Narbon vetch; common vetch) and two cereals (oat; triticale) were grown in three autumn-sown sites (Sassari, Italy; Sétif, Algeria; Marchouch, Morocco) for 2 years as pure stands and legume-cereal binary and four-component mixtures. We assessed dry matter yield, weed content and farmers' acceptability of the crops, and legume content and Land Equivalent Ratio of the mixtures. Legumes' competitive disadvantage ranged from very high in Sétif to nearly nil in Sassari. Pea- and common vetch-based mixtures out-performed Narbon vetch-based ones in terms of yield, legume content and farmers' acceptability. The tall pea, featuring greatest competitive ability against cereals, maximised the yield and legume content of legume-cereal crops. Vetch-cereal mixtures exhibited lower weed content than the average of the components' pure stands. Oat monoculture was top-yielding but modestly appreciated by farmers. Pea provided the only legume monoculture combining good yielding ability and high farmers' appreciation. Greater species diversity as provided by complex mixtures did not display any production advantage over binary mixtures. [ABSTRACT FROM AUTHOR]

Highlights: [•] We assessed yield and persistence of elite grass cultivars across Mediterranean sites. [•] Cultivar adaptive responses were modelled as a function of relevant climatic variables. [•] Our results support crop recommendation and breeding, also in view of climate change. [•] Tall fescue has general interest for Mediterranean drought-prone areas. [•] Completely summer-dormant cocksfoot with improved yield can be useful in warmer sites. [ABSTRACT FROM AUTHOR]

Abstract: Legume-based pastures can increase the forage feeding value, the self-provision of protein sources and the sustainability of grazing systems. This 4-year study provided further knowledge on adaptation of forage legume species and cultivars for pasture sowing in extensive livestock systems of inland Italian areas. Three cultivars of lucerne (Medicago sativa L.), two of birdsfoot trefoil (Lotus corniculatus L.) and two of sainfoin (Onobrychis viciifolia Scop.) were evaluated at Casina (northern Apennines) under cattle grazing and at Torricella Sicura (central Apennines) under sheep grazing in farms using rotational grazing with high stocking rates. Semi-erect lucerne and birdsfoot trefoil morphological types, presumably more grazing-tolerant, were compared with erect types. Species showed contrasting adaptive responses, with lucerne at Casina and birdsfoot trefoil at Torricella Sicura being highest ranking for overall dry-matter yield. Lucerne at the former location, and both lucerne and birdsfoot trefoil at the latter one showed the highest final ground cover. The kind of exploitation at Casina (mob-grazing) may have contributed to lower persistence of birdsfoot trefoil. Sainfoin mostly showed potential as a short-term grazing species. Performance of cultivars within species varied with location. Erect cultivars yielded and persisted as well as, or better than, semi-erect cultivars, possibly because of the adoption of rotational grazing and their Italian origin (implying possible better adaptation to local conditions). Erect cultivars of lucerne were specifically adapted to the geographical area in which they were selected. Specific adaptation and targeted intensity of grazing may be the main determinants in the choice of species and cultivars. [Copyright &y& Elsevier]

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 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]

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]