Search results for "Seed"
showing 10 items of 668 documents
Dianthus borbonicus (Caryophyllaceae), a new species from Sicily
2015
Dianthus borbonicus a new species occurring in North-Western Sicily is described and illustrated. It is a rare chasmophyte belonging to the D. sylvestris group, which is exclusive of a rupestrian stand near Rocca Busambra (Ficuzza). Its macro- and micromorphological features (seed testa sculptures, and leaf anatomy), ecology, conservation status and a comparison with the related species are provided too.
Correlations among fruit traits and evolution of different fruits within Melastomataceae
2000
Abstract The anatomy and morphology of nearly mature fruits in 85 mainly palaeotropical species of Melastomataceae were examined using microtome- and hand-sectioning, and differential staining. Much structural heterogeneity was observed in both capsules and berries. Multivariate analyses of 31 of the 52 characters recorded for each species, revealed that indehiscence is associated with fusion of ovary and hypanthium tissues, placenta persistence, lack of a persistent endocarp, and a dearth of sclereids in these tissues, while dehiscence is correlated with the opposite states and a persistent exocarp. Other fruit characters such as lignification or fleshiness of tissues do not show a consist…
Improvement of the nitrogen uptake induced by titanium (iv) leaf supply in nitrogen‐stressed pepper seedlings
1996
Abstract The beneficial effect of titanium (Ti) on plant metabolism can result in more profitable use of fertilizer applied to a crop. A crop chamber experiment with paprika pepper (Capsicum annuum L., cv. Bunejo) seedlings under differential nitrogen (N) concentration levels in a nutrient solution (100% N, 75% N, 50% N, and 25% N) was performed. A third of the seedlings growing under each N support level remained Ti‐untreated and were used as the reference. Another third of the seedling received one and two 0.042 mM Ti(TV) ascorbate, pH 6.0, leaf spray treatments, respectively. The biomass production of the Ti‐untreated plants was only affected by the N supply of 50% or less. The Ti(IV) le…
Morpho-physiological variations in response to NaCl stress during vegetative and reproductive development of rice
2012
The complex nature of plant resistance to adverse environmental conditions, such as salinity and drought requires a better understanding of the stress-induced changes that may be involved in tolerance mechanisms. Here we investigate stress-related morpho-physiological effects during vegetative and reproductive growth in two Japonica rice cultivars (Bomba and Bahia) exposed to a range of NaCl concentrations from the seedling stage. The stress-related detrimental effects were observed either earlier or to a higher extent in cv. Bomba than in Bahia. Damages to the photosynthetic apparatus were related to loss of chlorophyll (Chl) and to a decrease of the maximum potential efficiency of PSII (F…
Effect of rootstock on trunk growth and foliar mineral content in cv. Bianca pistachio (Pistacia vera L.) trees
1998
Trunk cross-sectional area (TCSA) and mineral content were recorded for 4 years in the major Sicilian pistachio cultivar, Bianca, budded in 1991 onto eight in v/fro-propagated clonal rootstocks (Pistacia atlantica and P. integerrima) and one seedling rootstock (P. terebinthus). The trees were grown using standard cultural practices for Sicilian dry-land farming in a fine sandy soil, located inland in Sicily (20 km SW of Palermo, 350 m a.s.l.). From nine trees per rootstock, samples of 10 leaflets from the mid-section of current year shoots were taken yearly in August and analyzed for the main plant mineral elements (N, P, K, Ca, Mg, Fe, Mn, Zn, Cu and B). The TCSA was measured at the end of…
Pollination biology in an endangered rocky mountain toadflax (Linaria cavanillesii)
2013
Knowledge about the reproductive system of species inhabiting rocky habitats is scarce. The reproductive biology (floral biology, experimental pollination, insect visits, inbreeding depression, and seed predation) of the rupicolous Linaria cavanillesii was analyzed under field and experimental conditions. Self-compatibility was revealed by the high fruit set, seed set, and seed mass in the pollination experiment. Furthermore, results disclose that this species does not need insect visitors for seed production since fruit set after autonomous self-pollination was similar to that by hand cross-pollination. Self-offsprings were not affected by a strong degree of inbreeding depression in early …
Does stump removal affect early growth and mycorrhizal infection of spruce (Picea abies) seedlings in clear-cuts?
2012
Abstract Stump removal procedure increases the extent of exposed mineral soil in the clear felled areas. In this study, our aim was to find out whether the early growth and mycorrhization of Norway spruce (Picea abies (L.) Karst.) seedlings differ between stump removal and mounding sites. Stumps were harvested from five one-hectare study sites and other five sites were mounded after clear felling. Twenty seedlings were planted on mounds at each study site. Although the height of spruce seedlings did not differ between the treatments after three growing periods, their mean growth was ca. 10% higher at the stump removal sites. The community of ectomycorrhizal (ECM) in the seedling roots did n…
New low-vigour apricot rootstocks compared
2010
About ten years ago nurseries began to test several novel apricot stocks developed either to reduce plant vigour and boost early as well as high cropping or as a more suitable replacement for Myrabolan (Prunus cerasifera) and Apricot seedling in water-logged or chlorotic soils. These stocks were the Italian bred selections of Prunus domestica Penta and Tetra, the P. cerasifera Adara and the Prunus insititia Adesoto® 101, both Spanish-bred seedlings, and Plumina@, a Prunus bessey × P. cerasifera hybrid developed in France. Performance testing was carried out under a national project. The trials were set up in 2001 in plots of pilot orchards at Imola in Bologna Province, Ancona, Caserta, Pale…
Seed germination in the Sicilian subspecies ofDianthus rupicolaBiv. (Caryophyllaceae)
2012
Abstract Five populations belonging to three subspecies of Dianthus rupicola Biv. (D. rupicola subsp. rupicola, D. rupicola subsp. aeolicus, and D. rupicola subsp. lopadusanus) and growing in different geographical areas of Sicily were tested for seed germination at various temperatures. All populations showed high germination rates with an optimum temperature between 15°C and 25°C. Efficient seed germination might contribute significantly to the preservation of these subspecies which are currently exposed to several environmental threats.
Growth increase of birch seedlings under the influence of earthworms—a laboratory study
1992
The effects of the earthworm Lumbricus rubellus (Hoffm.) on net production and nitrogen content of birch seedlings were studied in laboratory microcosms. Coniferous forest floors with litter, humus and mineral horizons were simulated in transparent plastic cylinders. The materials were partially sterilized by microwaving, and re-inoculated with microflora and -fauna. A young (9 cm) birch seedling (Betula pendula Roth) was planted in each container. Earthworms were added to half of the replicates. The microcosms, through which a constant air flow was maintained, were incubated in a climate chamber. After two growth periods, leaf and stem biomasses of birch in treatments with earthworms incre…