Olive pollination is anemophilous and an adult olive tree can produce large amounts of pollen grains spread in the air during the flowering period. Viability of pollen grains can be checked by using different methods such as cytoplasmic stains, enzymatic reactions or germination. The aim of the work was to verify either if quality and number of pollen grains were similar in 'off' year with respect to 'on' year or differences occurred among olive cultivars. In 2006 and 2007, the viability and number of pollen grains per anther have been investigated in four Italian olive cultivars: 'Ascolana Tenera', 'Cazzinicchio', 'Cima di Melfi' and 'Coratina'. Grains viability was estimated by using three different techniques: acetic carmine, fluorescein diacetate and germination. The three techniques obtained statistically different data, with acetic carmine always showing the highest values but staining also heat-killed pollen grains. Fluorescein diacetate and germination were significantly correlated with a high R2 (0.862). The number of pollen grains significantly varied among the cultivars and between the two years. The average number of pollen grains per anther ranged from 65,722 ('Ascolana Tenera') up to 97,160 ('Cazzinicchio'). A significant difference was detected between the two years for the number of pollen grains per anther, ranging from 98,037 in 2006 ('on' year) down to 70,630 in 2007 ('off' year). The study also showed that the viability (with all the techniques) of the pollen grains was significantly higher in the 'off' year with respect to the 'on' one, with important consequences on the fertilization process.

Abnormally developed pistils often occur in different apricot cultivars, as a consequence of physiological-biochemical factors and climatic conditions. Apricot is genetically prone to the formation of a high percentage of flowers morphologically hermaphroditic but physiologically unisexual due to pistil hypotrophy, atrophy and/or necrosis. The number of anthers, the amount of the total and stainable number of pollen grains per anther and per flower and flower (pistil) anomalies have been investigated in apricot (Prunus armeniaca L.) cultivars. Anthers and pollen were investigated for two years, 2004 and 2005, whereas flower bud differentiation and anomalies for three years, 2008, 2009 and 2010.Pistil hypo(a)-trophy anomalies occurred between the Baggiolini stages C and D and appeared to be significantly more frequent on the basal portion of long twigs with respect to either the apical portion or spurs and short twigs. All pollen characteristics taken into account varied significantly among the cultivars. The number of anthers per flower ranged from a maximum of 33.2 ('Rouge de Fournes') to a minimum of 22.6 ('Boccuccia Liscia'); the number of pollen grains per anther ranged from 2369 ('Kioto') to 1267 ('Ninfa'), and the pollen stainability was very high in all the examined cultivars (95.0-98.8%). The mean number of stainable pollen grains per flower was 57,149, ranging from 35,629 ('Boccuccia Liscia') up to 76,728 ('San Castrese'). These results indicate that cultivars both producing the greatest amount of stainable and compatible pollen grains per flower and bearing mainly on spurs or short twigs (lower flower anomalies) should be preferred either when planting new apricot orchards or for breeding programs.

The aim of this work was to define the most appropriate time of harvesting early ripening peach fruit using destructive and non-destructive quality indexes such as the index of absorbance (IAD), measured with the DA-Meter, a portable equipment able to measure the degradation of chlorophyll in the pericarp. In this context our research was carried out in 2009 and 2010 on several peach cultivars. Total soluble solid content increased while flesh firmness and total acidity decreased with IAD values, but no significant correlation was found between destructive and non-destructive parameters.