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The ‘pollen washes’ technique, based on the analysis of the pollen embedded in the porous surface of archaeological artefacts, is developed for investigating past plant usage and consumption and to characterize the functionality of artefacts related to plant processing, gathering and storage. The research presented results in relevant methodological improvements of this technique, which has never previously been applied on materials from European contexts. The improvements allow: (1) faster analysis of a broad series of artefacts or those with large use‐surface areas likely to retain more pollen; and (2) a more thorough, deeper and precise cleaning method, allowing the study of smoother artefacts. Finally, the recovery of Trifolium‐group pollen from a macro‐lithic tool from Xicotó rock shelter (Montsec ranges, Spain) demonstrates that the pollen washes technique can reveal new insights into both the use and consumption of wild and domestic plants by prehistoric societies, and the functionality of archaeological objects whose interpretation is still problematic. [ABSTRACT FROM AUTHOR]

Subterranean clover (Trifolium subterraneum) is an important forage legume in Mediterranean regions worldwide. Aphanomyces damping‐off and root disease (Aphanomyces trifolii) poses significant threat to its persistence and productivity. Studies were conducted to define how environmental explanatory variables (temperature, soil type, moisture, nutrition) and variety influence disease severity and consequent forage productivity and persistence. Relationships were modelled using linear and generalized linear models and boosted regression trees. Linear modelling highlighted complex relationships between environmental variables and each dependent variable (emergence, tap and lateral root disease, dry shoot and root weight). All environmental variables produced significant interaction and/or main effects within each dependent variable. Boosted regression trees supported the complex nature of relationships in linear models, with temperature and either soil or variety most, and nutrition least, influential. Heat maps showed more disease for low temperatures. Least tap root disease was under high temperatures, while least lateral root disease was under medium or high temperatures, low moisture, and in sand‐based soil. These are the first studies using modelling approaches to reveal the complexities of how fluctuating soil temperature, moisture and nutrition conditions, and soil type and variety, determine aphanomyces damping‐off and root disease severity and resultant adverse impacts on forage legume productivity and persistence. Outcomes are widely applicable across soilborne oomycete pathogens of forage legumes. Studies highlighted how warming temperatures and drying climate associated with climate change should reduce future impact and importance of this and other soilborne oomycete diseases of forage legumes favoured by cold temperatures and wet and waterlogged conditions. [ABSTRACT FROM AUTHOR]

Key message: Review on citrus reproduction.Abstract: Citrus is one of the most important and widely grown fruit crops. It possesses several special reproductive characteristics, such as nucellar embryony and self-incompatibility. The special phenomenon of nucellar embryony in citrus, also known as the polyembryony, is a kind of sporophytic apomixis. During the past decade, the emergence of novel technologies and the construction of multiple citrus reference genomes have facilitated rapid advances to our understanding of nucellar embryony. Indeed, several research teams have preliminarily determined the genetic basis of citrus apomixis. On the other hand, the phenomenon of self-incompatibility that promotes genetic diversity by rejecting self-pollen and accepting non-self-pollen is difficult to study in citrus because the long juvenile period of citrus presents challenges to identifying candidate genes that control this phenomenon. In this review, we focus on advances to our understanding of reproduction in citrus from the last decade and discuss priorities for the coming decade. [ABSTRACT FROM AUTHOR]

Mealybugs are major pests in grape-growing areas worldwide, causing direct and indirect crop damage. The vine mealybug Planococcus ficus ( Signoret) is a key pest in most of grape-producing countries, whereas the citrus mealybug Planococcus citri ( Risso) is reported as being destructive in Brazilian and Spanish vineyards., We examined the adaptation of the citrus mealybug to grapevine by investigating its development, reproduction and life-history parameters under Mediterranean field conditions in comparison with those of P. ficus., Both mealybug species developed and reproduced successfully on grapevine. However, P. ficus showed a shorter development time, larger female body size, and higher fecundity, fertility and survival than P. citri., The life-history parameters further highlighted the different growth potential of vine and citrus mealybug populations because P. ficus exhibited a net reproductive rate and an intrinsic rate of increase two- to four-fold higher than that of P. citri. Furthermore, the vine mealybug population doubled its number in approximately half time with respect to the citrus mealybug., Overall, the results of the present study show a better development and reproductive performance and a higher population growth potential of P. ficus compared with P. citri, indicating a higher capacity of the vine mealybug to develop on grapevine in Mediterranean vineyards. [ABSTRACT FROM AUTHOR]

This in vitro study provides a new insight into the phytochemical, antioxidant, antiplatelet and cytotoxic profiles of commercial trans -clovamide and clovamide-rich extracts, isolated from aerial parts of three Trifolium species (i.e. T. clypeatum L., T. obscurum Savi and T. squarrosum L.). Under inorganic experimental conditions, the EC 50 for the investigated substances varied between 4.87 (clovamide) and 7.91 μg/ml ( T. clypeatum ) according to the DPPH • assay. The most effective 1 mM ONOO − scavenger was clovamide (IC 50 = 19.29 μg/ml), and the weakest was the T. obsucurum extract (IC 50 = 41.79 μg/ml). The antioxidant action of the examined substances (1–50 μg/ml) was also evaluated in blood plasma (under 100 μM ONOO − -induced oxidative stress) using 3-nitrotyrosine, protein thiol groups, lipid hydroperoxides and thiobarbituric acid-reactive substances as biomarkers. All examined substances were more effective in limiting the oxidative damage to blood plasma components than the nitrative damage. Their anti-nitrative action was statistically significant only at the highest concentration (50 μg/ml). Measurements of platelet adhesion and aggregation found the compounds to have moderate antiplatelet properties of up to 20% inhibition of platelet adhesion at concentrations of 1–5 μg/ml. Additionally, clovamide and Trifolium extracts demonstrated no cytotoxicity towards blood platelets or peripheral blood mononuclear cells. [ABSTRACT FROM AUTHOR]

The topic of this research was to test a chemometric technique (Principal Components & Classification Analysis) to reflect some characteristics of a real case: the influence of fertilization management on FRAP antioxidant activity in summer of grassland perennial forages. An area of 25 m2 for each experimental trial was organised, with five replications, in complete randomized blocks design. StatSoft - STATISTICA, version 10, performed the chemometric matrix. Ten cases were included, nine of them with different fertilization management and one unfertilized. It was applied fermented sheep manure and/or mineral fertilizers based on NPK since 2003. The active variables of PC&CA were: the fertilization data, soil pH and the gravimetric percent of the spontaneous plants Calamagrostis epigejos (Ce%), Festuca rupicola (Fr%), Trifolium repens (Tr%), Inula britannica (Ib%), Filipendula vulgaris (Fv%) and Rosa canina (Rc%). The supplementary variable was the perennial feed FRAP antioxidant capacity. The coefficient for soil pH and Trifolium repens (%) correlation was 0.8, while in Calamagrostis epigejos (%) and Festuca rupicola (%) cases the coefficients were negatively: -0.6, respectively -0.8. Positive coefficients were obtained in summer for the correlations between grassland perennial feed FRAP antioxidant activity and Inula britannica (%), respectively Rosa canina (%). Principal Components & Classification Analysis can reflect as a mirror the perennial forage FRAP antioxidant activity at low pH, as grassland functional feed for animal, depending on fertilization management. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi can establish associations with over 80% of land plants. Most important beneficial effects for plants are: phosphorus availability, increased resistance to abiotic and biotic stress. Studies regarding the effects of mycorrhization on ornamental plants in our local pedoclimatic conditions are almost inexistent. The aim of this study was the evaluation of mycorrhizal inoculum effect over some vegetative characteristics for six Iris germanica cultivars. The experimental field was settled in Botanical Garden of UASVM Cluj-Napoca. For each cultivar were established two treatments: non-inoculated and inoculated with mycorrhizae. Results indicate that regarding the percentage of buds that entered vegetation in spring was higher for inoculated plants compared to non-inoculated plants. Inoculated cultivars 'Sultan's Palace' and 'Pinafore Pink' had a higher number of shoots grown in spring than number of buds present in autumn. For most of the studied cultivars the mycorrhizae products exercised beneficial effects regarding the entering in vegetation of buds, or stimulating formation of new buds. This phenomenon is attributed both to mycorrhizal fungi and auxins added to inoculum. [ABSTRACT FROM AUTHOR]

White clover living mulch (LM) increases the uptake of phosphorus (P) and the yield of the main crop by promoting the colonization of arbuscular mycorrhiza (AM). However, the extent to which the P fertilizer application rate can be reduced by using LM is not yet known. This study aimed to address this question. Two field experiments were conducted from 2008 to 2009 (Experiment 1) and from 2009 to 2010 (Experiment 2) at the fields where the available P of soil fluctuated near the lower limit of the optimum P level (43.6 mg kg −1 : Truog method). Experiment 1 had a randomized block design, and Experiment 2 had a split-plot design with a factorial arrangement of two cropping systems (LM and no LM) with three P application treatments (0 kg ha −1 , 43.6 kg ha −1 , and 87.3 kg ha −1 ). LM increased P concentrations in the early stages of growth and the yield of corn. This can be attributed to the increased AM colonization rate in the early stages of growth. The yield and total digestible nutrient yield of corn in LM with no P application was comparable to the maximum yield in no LM with or without P application. Therefore, LM could make unnecessary P fertilization in soils where P fertilization is required for silage corn. [ABSTRACT FROM AUTHOR]

Genetic resources of red clover (Trifolium pratense L.) are the basis for the improvement of this important forage legume. The objective of this study was microsatellite characterization of the accessions from the collection of the Institute of Field and Vegetable Crops in Novi Sad, Serbia. Molecular evaluation of 46 red clover genotypes was performed by applying the set of 14 primer pairs of microsatellite markers. These primer pairs amplified a total of 187 alleles, with an average of 13.36 alleles per locus and average polymorphism information content (PIC) value was 0.306. The minimum values of Dice genetic distances based on polymorphism of microsatellite markers were found among genotypes NCPGRU2 and NCPGRU5 (0.311) and the highest values of genetic distances were determined for a couple of genotypes Violeta and BGR2 (0.933). The average genetic distance between all pairs of genotypes amounted 0.587. The results of the principal coordinate analysis (PCoA) were consistent with the results obtained on the basis of cluster analysis, except that the PCoA allocated another four genotypes. There was no relationship between groups of genotypes formed by the use of cluster analyses and PCoA with their geographical origin. Analysis of molecular variance of 46 red clover genotypes by the status and ploidy level was significant, but it also suggested a weak genetic differentiation of groups formed on the basis of those characteristics. Observed groups of genotypes, according to the cluster analyses and PCoA of microsatellite data, could be used in future breeding programs for the selection of germplasm. [ABSTRACT FROM AUTHOR]

Maximum aphid numbers on wheat are positively related to the length of the period elapsed from immigration to the population peak. We predicted that maximum abundances on late maturing cultivars would be greater than on early ones. This was tested using 8 spring wheat cultivars that differed in the length of time to senescence. In a 4-year experiment, numbers of aphids were checked at weekly intervals. Maximum abundances on late-maturing cultivars were significantly greater than those on early cultivars. However, the length of the vegetation period affected maximum abundances less than did the annual variation in aphid abundance. Genetic disposition for early ripening thus tends to decrease aphid numbers, but manipulation of this character is unlikely to become an important source of aphid resistance. [ABSTRACT FROM AUTHOR]

Sulfur dioxide (SO2) is one of the most common and harmful air pollutants. High concentrations of SO2 can cause stress and limit growth in plants. Some of the plants can resist stress by bacterial symbiosis such as Rhizobium symbiosis. Rhizobium is a beneficial bacterium that enhances plant growth and yield. To study the effects of SO2 pollution on growth indexes, protein, proline and sulfur contents, 31 days old plants of Trifolium resupinatum (Persian clover), inoculated with native and standard Rhizobium were exposed to the different concentrations of SO2 (0 as control, 0.5, 1, 1.5 and 2 ppm) for 5 consecutive days. Results showed that inoculation increased leaf area, leaf number, shoot height, root length, shoot fresh and dry weight and protein content of Persian clover but didn't show any significant effect on proline and sulfur contents. Different concentrations of SO2 had a significant effect on leaf number, shoot height, root length, shoot fresh and dry weight, protein, proline and sulfur contents but didn't have effects on leaf area. 0.5 ppm concentration of SO2 increased growth indexes and protein content. Proline and sulfur contents didn't change in 0.5 ppm. Increasing SO2 decreased growth indexes and protein, and increased proline and sulfur contents. Interaction between Rhizobium inoculation and SO2 treatment improved the stress effects of high concentrations of SO2 on growth indexes, protein, proline and sulfur contents. It was therefore concluded that Rhizobium can increase tolerance and resistance of this plant to the abiotic stresses such as SO2 pollution. [ABSTRACT FROM AUTHOR]

Uptake of barium (Ba) from soil by vascular plants varies among species. Despite the toxicity of soluble Ba compounds to plants, research on mechanisms controlling Ba uptake from natural soils is scarce. This study investigated the treatment effect of lime (CaCO3) added to a sandy soil containing a total of 500 mg Ba kg−1 on uptake and interspecies distribution of Ba in legumes and other cultivated food and feed plants. Nine species of grasses, vegetables, herbs, and legumes were cultivated under controlled conditions in a greenhouse experiment. The plants were harvested at maturity or flowering, dried, milled, and digested with nitric acid using the microwave technique prior to ICP-MS analysis. All plant species acquired Ba from the soil in considerable amounts, probably due to low Ba adsorption potential of the sandy soil. Shoot tissue concentrations ranged from about 100 (grass) to 600 mg Ba kg−1 (legume) and root concentrations from about 100 (tuber vegetable) to 700 mg kg−1 (legume). Vicia cracca L. (bird vetch) showed an accumulation capacity due to high shoot concentrations of Ba compared to the other species. Higher yield accompanied by a potential dilution effect can partly explain why Trifolium repens L. (white clover), Pisum sativum ssp. arvénse L. (gray pea) and Hordeum vulgare L. (barley) did not display the highest Ba concentrations, but showed the highest Ba uptake from soil. High plant uptake of calcium (Ca) also seemed to enhance Ba uptake, by legumes in particular. However, liming reduced shoot Ba concentrations, particularly of species with low affinity for Ca. The risk of Ba accumulation thus raises toxicity concerns when forage legumes are cultivated in soils containing elevated concentrations of Ba. [ABSTRACT FROM AUTHOR]

Cacti are transplanted when their occurrence conflicts with road and pipeline construction and mitigation requires relocation, or they are transplanted for personal use. Methods used in transplanting have credence by virtue of common practice; however, there are few scientific studies comparing different methods. Our objective was to determine if different transplanting techniques, time of year of transplanting, and association with a nurse plant upon transplanting affected the long-term survival (8 years) and vigor of Sclerocactus parviflorus (Clover and Jotter). The 3 transplanting procedures were as follows: (1) cacti excavated, soil removed from roots, roots trimmed, plants placed in shaded open environment for 2 days and then transplanted (modification of conventional procedure); (2) cacti excavated to maintain a root ball and transplanted within 2 hours; and (3) cacti excavated, soil shaken off the roots and transplanted within 2 hours. Mortality was documented every spring and fall for 8 years. Plant vigor was determined in the eighth year by measuring flower and tubercle production. There was no difference in cactus survival among the 3 transplanting techniques, time of year of transplanting, and association with a nurse plant. There was no difference in vigor among the treatments as measured by flower and tubercle production. Three years after transplanting, 97% of the cacti were alive, and after 8 years 84% were alive. Based on this study, transplanting of S. parviflorus with high long-term survival can be done by any of these procedures, at any time of year, and with or without an associated nurse plant. [ABSTRACT FROM AUTHOR]

The aim of this work was to develop a red clover variety adapted to agro-climatic conditions of Latvia, suitable for different requirements of forage producers, resistant to most widespread diseases and producing high seed yield annually. Medium late ripening diploid red clover variety 'Jancis' was created at the LLU Research Institute of Agriculture in long-term work carried out since 1985. After free pollination of best samples of red clover collections from the VIR (St. Petersburg), individual and family selection among hybrids were carried out for approximately 20 years. Finally, best breeding line Nr. 43047 was registered as a variety 'Jancis'. The variety is characterised by good winter hardiness, high dry matter yield (10-12 t·ha-1) and good persistence in the sward - up to 3-4 years. The variety is characterised by a long stem (90-110 cm) with 8-9 internodes, dark green leaves with a distinctive brighter picture, medium length and width of medial leaflet, and bright pink flower heads. 'Jancis' has stable annual seed yield in the conditions of Latvia; under favourable conditions reaching 500- 600 kg·ha-1 seeds. Since 2010, the variety 'Jancis' has been included in the common Latvian and EU Plant Variety Catalogue. [ABSTRACT FROM AUTHOR]

The article discusses fatty acid compositions of seeds of "Trifolium" species with highest diversity is found in Turkey. It is suggested that legumes are the important food source and play a significant role in traditional diets in many regions of the world. Other topics addressed include palmitic and stearic acids of seed oils of Trifolium species and the major unsaturated fatty acids found in the seed oils including oleic, linoleic and linolenic acids.

Various chemical tests are being used to reveal chemical differences among the seeds or seedlings of different cultivars. Study to characterize and identify 24 tomato cultivars based on chemical test chemicals viz., Standard phenol test, Modified phenol test, NaOH test, KOH test and Seedling growth response to added chemicals reveled that, most of the cultivars studied were distinct from other cultivars. No single chemical test could distinguish all the varieties. However, distinguishable chemical characteristics were used to develop the keys for identification of each and every cultivar and all the cultivars were distinguished based on these identification keys. [ABSTRACT FROM AUTHOR]

Abstract: Selected engineering properties of seeds of four red clover varieties were studied. The seeds of diploid and tetraploid forms were statistically different in terms of true and bulk density, porosity, volume, 1000 seed weight, equivalent diameter and yellowness index. The volume, 1000 seed weight and equivalent diameter were found to be statistically higher for tetraploid than for diploid forms. The accuracy of varietal classification based on the physical properties of seeds was found to be most satisfactory. Varieties of Bona and Jubilatka were identified with 100% accuracy based on the physical properties of seeds. Bona was the most conducive variety for the classification of red clover seeds based on four groups of engineering properties. The relationships between groups of properties described by total redundancy did not exceed 50% for any of variable pairs. [Copyright &y& Elsevier]

Phosphorus (P) is often reported as a nutrient whose availability increases by lime application, although some research suggests a decline in the short-term P availability upon liming. This study addresses the effects of applying different sized limestone (2-4, 0.5-2, 0.25-0.5, and <0.25 mm) on the forms and availability of soil P, P concentrations and extraction by pasture, and yields of plant species. Soil P was partitioned into organic and inorganic forms, using an ignition method. Available P was determined by the Olsen and Mehlich 3 methods. Phosphorus in plants was determined after acid digestion. Most P was present in organic form. One year after sowing, inorganic P increased and organic P decreased. Liming had no significant influences on soil P. Phosphorus extracted by Mehlich 3 explained 40% of the total dry-matter yield in the first harvest. No significant effect of liming on P concentration in plants was observed. [ABSTRACT FROM AUTHOR]

Some modern agrochemicals with antioxidant potential were tested for their protective effect against ozone injury using clover and tobacco ozone-sensitive cultivars as model plants subjected to ambient ozone at two sites (Kyiv city in Ukraine and Szarów village in Poland). All used agrochemicals showed partial protective effects against ozone injury on clover and tobacco. Conducted studies confirmed the effectiveness of modern fungicides belonging to strobilurin group as protectants of sensitive crops against ozone damage. The effectiveness of new growth regulators "Emistym C" and "Agrostymulin" was showed for the first time. Out of the studied agrochemicals, fungicide "Strobi" and natural growth regulator "Emistym C" demonstrated the best protective effects. These agrochemicals present promise for further studies of their possible utilization for enhancement of ozone tolerance of sensitive crops. [ABSTRACT FROM AUTHOR]

Red clover (Trifolium pratense L.) is botanically a perennial, although it often behaves as a biennial. The crop usually lives 2 to 3 seasons in most clover-growing regions of the world and is generally conceded to be lacking in persistence. The objective of this investigation was to analyze the production potential and persistence of domestic and imported red clover varieties. Experiments were conducted at Rimski Sancevi Experiment Field during the period 2004-2006. The experimental materials were six varieties (K-17, Kolubara, Una, Viola, Start, Nike) which were analyzed for the most important production characteristics: yield of green mass, dry matter yield and persistence. [ABSTRACT FROM AUTHOR]

The present review examines the main attributes and agronomic characteristics of arrowleaf clover (Trifolium vesiculosum Savi) and its incorporation into production systems in dryland areas of the Andean foothills of the humid Mediterranean climate zone of Chile. It is a new species of annual legume in Chile for light and medium textured soils. The root system can reach a depth of 1.5 m and its seeds have a high percentage of hardseedness (99.8%). It is an upright plant, with purplish-white flowers. The mature plant has large arrow-shaped leaves up to 50 mm long, often marked with a large white "V". Dry matter and seed production in the Andean foothills is high (3.9-8.8 t DM ha-1 and 700-900 kg ha-1, respectively), surpassing the productivity of sub clover (Trifolium subterraneum L.) cv. Mount Barker and crimson clover (Trifolium incarnatum L.). However, DM production in the second year was lower, possibly because the high percentage of hardseedness inhibited plant emergence. The phenological records and productive performance suggest that arrowleaf clover could contribute to improving pastoral production in dryland areas with annual rainfall levels of more than 800 mm, such as the Andean foothills in the central-southern region of Chile. [ABSTRACT FROM AUTHOR]

Plants in Nordic regions can be more ozone sensitive at a given ozone concentration than plants at lower latitudes. A recent study shows that the Nordic summer photoperiod, particularly the dim nighttime light, can increase visible foliar injury and alter leaf transpiration in subterranean clover. Effects of photoperiod on the ozone sensitivity of white and red clover cultivars adapted to Nordic conditions were investigated. Although ozone induced visible foliar injury and leaf transpirational changes in white clover, the effects were independent of photoperiod. In red clover, ozone combined with a long photoperiod with dim nights (8 nights) induced more severe visible injuries than with a short photoperiod. Furthermore, transpirational changes in red clover depended on photoperiod. Thus, a long photoperiod can increase ozone sensitivity differently in clover cultivars with different degrees of adaptation to northern conditions, suggesting that ozone indices used in risk analysis should take this effect into account. [ABSTRACT FROM AUTHOR]

The total amount and the composition of varieties of all forage grass and clover seed delivered for farm use in Northern Ireland was monitored over the 25-year period of 1980–2004. Total seed use in Northern Ireland declined from the 1980s to the 1990s but then stabilized despite isolated drops in sales associated with outbreaks of animal diseases. This profile was mirrored by similar declines in the rest of the UK. The survey revealed the annual volatility of the market and its sensitivity to changes in government financial support, to changes in farm practice and farm incomes. Examination of the data on the grassland area under 5 years old showed them to be poor indicators of actual seed use. Levels of species use were very stable over the 25 years of the survey but reseeding of varieties of perennial ryegrass differing in maturity and ploidy type changed dramatically. When sufficient seed was available, selection of varieties complied with the contemporary recommended list ratings of agronomic value but in a few cases selection of varieties was determined by price. The current survey of seed sales provides a benchmark against which responses by farmers following the latest changes in the Common Agricultural Policy of the European Union can be measured. [ABSTRACT FROM AUTHOR]

Dry matter content in overground biomass in six varieties and four breeding populations of white clover (Trifolium repens L.) were studied at the Lithuanian Institute of Agriculture (Dotnuva) during the period 2001-2003. In this study, the AMMI model was used with the objective of assessing dry matter content in the overground biomass of white clover genotypes, selecting stable genotypes and investigating genotype by environments (G x E) effects. The effects of environments, genotypes and G x E interaction were highly significant (P < 0.01). The first two bilinear AMMI model terms accounted for 88%. The biplot showed three groups of genotypes: Nos. 1123 and 1124 unstable but high-yielding; varieties 'Suduviai', 'Bitunai', 'Atoliai' and No. 1421 stable but low or medium yielding; variety 'Nemuniai', 'Rivendel' and No. 1435 unstable, low or medium yielding. To breed a new ecologically stable variety of white clover we intend to use the variety 'Nemuniai' and No. 1124 as initial material for hybridization. They have a high level of dry matter productivity but differ by GE response. [ABSTRACT FROM AUTHOR]

The article discusses ways of preventing rabbits from destroying plants. One strategy is to plant the four-leaf-clover variety on the lawn since rabbits prefer the clover to fruits or vegetables in the garden. According to the author, a pet Bengal cat that eats rabbits and other animals helps control plant damage in the garden.

Presents information on a hexaploid backcross of the hybrid Trifolium ambiguum. When the backcross was released; Detailed information on the backcross.