1,721,000 research outputs found
Coltura in vitro dell’olivo: applicazioni alla conservazione e valorizzazione della biodiversità. Workshop La coltura in vitro applicata alla conservazione e alla valorizzazione della biodiversità vegetale
No full textMorphological structure of the stigma and style of several genotypes of Prunus armeniaca L.
No full textThe morphology of the stigmatic surface and style of apricot (Prunus armeniaca L.) is described, in order to extend current knowledge of stylar and stigmatic structures. Eight apricot cultivars of different geographical origin and characterised by a different self-compatibility behaviour were analysed. Whole pistils were removed from flowers at different phenological stages. Analyses were performed on frozen-hydrated specimens by Low-Temperature SEM. Morphological observations were conducted on: stigma (shape, size and presence of exudate), stigmatic papillae (shape, size, density and distribution) and style (inner structures). A comparative study of thr different apricot cultivars showed several morphological differences related to the genotype
Fertility problems in cv. Antonio Errani: stigma pollen interaction.
No full textCultivar "Antonio Errani", selected in 1975 by our Department, was recently introduced in different cultivation areas in Italy. This cultivar is endowed with noteworthy organoleptic and commercial characteristics, but in some environments it is affected by poor and irregular fruiting. In the present study, some aspects of the floral biology of this variety were studied, in order to investigate possible causes of this infertility. Research focused on observation of compatibility and morphological analysis of the micro-gametophyte (characterization of pollen grain shape, viability and germination ability) and the macro-gametophyte (morpho-anatomic analysis of stigma structure by Scanning Electron Microscope observations). Directly on the stigmatic surface, observations were also carried out on pollen-pistil interaction, pollen retention on the stigma and germination ability. Moreover the pollen tube elongation in the style up to the ovary was observed. Results showed no anomaly involving the micro-gametophyte. Self-compatibility of the variety was confirmed, but poor pollen retention on the stigma was found, together with slow elongation of the pollen tube up to the ovary. Scanning Electron Microscope observations revealed early degeneration of stigmatic papillae, which were seen to be collapsed and therefore unable to retain pollen grains
Rodentomyces, a new hypocrealean genus from Italy
No full textAn ascomycete with non stromatic, narrowly ovoidal or subpyriform, pale yellow to luteous perithecia, a Nectria-like centrum, yellowish-brown reticulate ascospores, and a Trichothecium-like anamorph has been isolated from small rodent dung in Italy. Based on morphological, cultural and molecular (nrLSU and ITS sequences) data, a new genus, Rodentomyces, and a new species, R. reticulatus, are therefore introduced to accommodate this fungus. Rodentomyces represents a hypocrealean genus in the Nectriaceae. Within this family, and based on molecular data, R. reticulatus is placed in the group including Calonectria, Leuconectria, Nectricladiella, Neonectria and Nectria mariannaeae. Several coprophilous genera are recorded in Hypocreales almost evenly distributed among the main families of this order
Caratterizzazione morfologica della superficie stigmatica in diverse cultivar di albicocco.
No full textThe response of sugar beet to drip and low-pressure sprinkler irrigation in southern Italy
No full textScarce water resources frequently limit crop production in semi-arid lands. Drip irrigation may constitute a method for sagacious management of water resources, but there is still limited information on its use for sugar beet crop in Mediterranean environments. The present study was conducted to determine the effect of irrigation on sucrose accumulation and root yield, as well as on sugar beet physiological responses, and to compare drip and low-pressure sprinkler (high efficiency) irrigation performances for sugar quality. As the main scope of the study was to give indications to allow water saving, the comparison focused on the best irrigation method when a similar amount of water was applied. Sugar beets were grown in an experimental field site in southern Italy (Molise Region) for two consecutive growing seasons (1999/2000 and 2000/2001). The water applied ranged from 50, 75, and 100% of the estimated evapotranspiration (ET); unirrigated sugar beets were taken as control plants. In both years, harvest was completed in two periods. Increasing volume of water replaced was advantageous for crop performances, and yield and physiological responses of sugar beets drip irrigated with 75% of estimated ET matched in most cases those of low-pressure sprinkler irrigated with 100% of estimated ET, resulting in potential 25% of water volume saving. In general, drip irrigation influenced positively many of the considered physiological and technological parameters, as compared to low-pressure sprinkler irrigation. Differences in root production and sugar quality between the two harvest periods were not significant. Results indicate that (1) increasing the amount of water applied gives benefits in terms of sugar beet root yield and sucrose accumulation, (2) drip irrigation (even applied every-other-furrow) appears to be consistently advantageous with respect to low-pressure sprinkler irrigation for sugar beet performances in semi-arid environments, (3) there are indications that suggest sugar beet growers should harvest in advance (of traditional harvest dates
Dasineura oleae: morphological and physiological characterization following the midge attack on olive leaves.
No full textPhysiological response of two plive genotypes to gaseous pollutants
No full textPhysiological and morphological responses of young olive plants (Olea europaea cvs Frantoio and Moraiolo) exposed to SO2 vapors (0, 35, 70, 100 ppb for 150 d), and different O3 regimes (a single pulse of 150 ppb for 5 h and 0, 50 or 100 ppb for 5 h d for 120 d), were measured by an infra-red gas analyser. LTSEM observations were performed on cryofixed specimens kept frozen-hydrated during analysis. SO2 and O3 fumigated plants highlighted a different genotype response. No visible symptoms were induced by SO2, while symptoms appeared in the long-term O 3 treatment after 100 days in Moraiolo. The physiological and morphological effects observed were capable to induced a depression in photosynthetic activity and in transpiring surface. These depressions can cause a decrease in growth and yield parameters over a long growing period
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