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Aims: The effects of freeze-drying, spray-drying and fluidized bed-drying on survival of Epicoccum nigrum conidia were compared. Methods and Results: Viability of E. nigrum conidia (estimated by measuring its germination) was 100% after fluidized bed-drying and freeze-drying, but it was determined that skimmed milk must be added in the case of freeze-drying conidia. Addition of other protectants (Tween-20, peptone, sucrose, glucose, starch and peptone + starch) to skimmed milk before freeze-drying did not improve the conidial viability which was obtained with skimmed milk alone. Glycerol had a negative effect on the lyophilization of E. nigrum conidia. Epicoccum nigrum conidia freeze-dried with skimmed milk, or fluidized bed-dried alone maintained an initial viability for 30 and 90 days, respectively, for storage at room temperature. Epicoccum nigrum conidial viability after spray-drying was lower than 10%. Conclusions: The best method to dry E. nigrum conidia was fluidized bed-drying. Conidia without protectants dried by this method had 100% viability and survived for 90 days at room temperature. Significance and Impact of Study: This paper deals with methods for the potential formulation of a biocontrol agent which is being tested for eventual commercialization.

Aims:  To study the population dynamics of Epicoccum nigrum on peaches and nectarines and to enhance its colonization on fruit surfaces to improve its biocontrol efficacy against brown rot. Methods and Results:  Twelve surveys were performed to study E. nigrum populations and their effect on the number of the pathogenic Monilinia spp. conidia in peach orchards in Spain and Italy between 2002 and 2005. Fresh conidia and five different formulations of E. nigrum conidia were applied three to six times to peach and nectarine trees from full flowering to harvest. The size of the E. nigrum populations was determined from the number of colony‐forming units and conidial numbers per flower or fruit. Treatment with all conidial formulations increased the size of the indigenous conidial population on peach surfaces. Conclusions:  Formulations of E. nigrum having high viability are most effective against conidia of the pathogen when applied at pit hardening and during the month immediately before fruit harvest. Significance and Impact of the Study:  Application of an E. nigrum conidial formulation decreased the number of conidia of Monilinia spp. on fruit surfaces during the growing season to the same extent as fungicides.

In the framework of the study of the mode of action of biocontrol agents (BCAs) it is important to know if BCAs are antibiotic-producers. Epicoccum nigrum 282 and Candida sake CPA-1 are BCAs effective against post-harvest pathogens of stone and pome fruits. The antibiotics produced by these BCAs and the relationship to biocontrol were studied. Production of antibiotics by E. nigrum in in vitro cultures began at 5 days of incubation being maximal at different times depending on media used. However, no antibiotic was detected when E. nigrum was grown in a solid state-fermentation system or in peaches. In the case of C. sake, no antibiotic was detected either in vitro, in liquid fermentation cultures of the yeast, or in apples.

For olive genetic improvement work it is very important to obtain a high rate of seed germination and a shortening of the juvenile period of the plants raised. By in vitro embryo culture, a 100% of germination is attained in a few days and the supply of adequate nutritive solutions and photoperiod speeds up seedling development during hardening, thus shortening juvenility. Mycorrhizal is another resource to improve plant development. This work attempts to know the effect of the vesicular-arbuscular mycorrhizal Glomus intraradices on the survival and development of olive seedlings obtained by in vitro embryo germination, during greenhouse hardening phase.Olive seedlings obtained by in vitro embryo germination were transplanted to pots with sterile sandy soil. Half of the pots were inoculated with 5g of Glomus intraradices. Afterwards, the pots were transferred to a greenhouse and watered at field capacity. After 180 days in this conditions, the number of dead plants, stem and shoot length of the surviving plants, and leaves, stems, shoots, roots and whole plant fresh and dry weight were recorded. Also, the nutritive status of the above indicated organs was analysed.