In the present study a number of compounds (acibenzolar-S-methyl, mineral and organic 12 fertilizers, plant extracts), known for their capability of inducing resistance in plants to several 13 pathogens, were tested in 2011 and 2012, in comparison with registered fungicides, cupper-based 14 fungicides and biocontrol agents, to control downy mildew of sweet basil (Ocimum basilicum L.), 15 incited by Peronospora belbahrii. Four experimental trials were carried out under glasshouse 16 conditions in the presence of a high disease incidence. The tested compounds were used alone or 17 applied in rotation in spray programmes. In all trials the best results, in terms of reduction of disease 18 incidence and disease severity were offered by metalaxyl-M + copper hydroxide, by the mineral 19 fertilizer Alexin, by mandipropanid and by azoxostrybin, followed by the glucohumates activator 20 complex and acibenzolar-S-methyl. Such products did significantly reduce disease incidence and 21 severity also 20 days after the last treatment. Among the copper-based products, the best results 22 were provided by copper hydroxide with terpenic alcohols and copper oxychloride + copper 23 hydroxide. The mineral fertilizer Kendal and prohexadione calcium, the biocontrol agent B. subtilis 24 QST 713, thyme oil extract and mustard oil on the contrary, were not effective. When different 25 combination of various products used in rotation were tested, it was possible to reduce disease 26 incidence and severity with different strategies, based on the rotation of fungicides and resistance 27 inducers as well as with the rotation of resistance inducers. 28 29

13Four plot trials were carried out under controlled conditions in order to evaluate the effectiveness 14 against Fusarium wilt of rocket (Fusarium oxysporum f. sp. conglutinans) and basil (F. oxysporum 15 f. sp. basilici), of soil amendments based on a patented formulation of Brassica carinata defatted 16 seed meal and compost, combined or not with a simulation of soil solarization. The soil solarization 17 treatment was carried out in a growth chamber by heating the soil for 7 and 14 days at optimal (55 18 to 52°C for 6 h, 50 to 48°C for 8 h and 47 to45°C for 10 h/day) and sub-optimal (50 to 48°C for 6 19 h, 45 to 43°C for 8 h and 40 to 38°C for 10 h/day) temperatures similar to those observed in 20 summer in solarized soil in greenhouses in Northern Italy. Two subsequent cycles of cultivation 21 were carried out in the same soil. Even at sub-optimal temperature regimes, 7 days of thermal permits a significant increase in the biomass, with a positive effect on yield. 28Key words: Thermal treatment; biofumigation; compost; Fusarium oxysporum f. sp. to soil in order to control soilborne pathogens has been widely studied and exploited, since it 37 represents a low cost and ecologically sound method (Gamliel and Stapleton 1997). Organic 61The incorporation of soil amendments can improve the efficiency of solarization, by 62 extending the spectrum of pathogens controlled, reducing the solarization duration, and preserving 63 soil microbial communities from the negative effects of heating (Stapleton 1984; 2000; Klein et al. 64 2011 b; Tjamos et al.2000). Previous studies carried out under field conditions showed improved 65 control of Fusarium wilt and dry root rot of clusterbean by combining 14 days of soil solarization 66 with urea and farmyard manure application (Lodha 1995 soil) and peat substrate (Tecno 2, 70% white peat and 30% clay, pH 5. 5-6, N 110-190 Italy (Gullino et al. 1998; Tamietti and Garibaldi, 1987). Immediately before starting the trial, soil 109In all four trials, at the end of each thermal treatment carried out under growth chamber conditions, 110 treated and untreated soil was transferred into 10 plastic pots of 2 L capacity and kept in a 111 greenhouse with temperatures ranging from 25 to 28 °C and 70-80 UR% (Table 2). 112Plants of cultivated rocket (Eruca sativa, cv. Coltivata, Bertolino) and basil (Ocimum basilicum, cv. 113Fine verde, Furia Sementi), both highly susceptible to Fusarium wilt, were used. Rocket seeds were The methodology used for soil infestation led to a good disease incidence in the control 159 plots in all trials for both pathogens on the two crops (Tables 2 to 5). The disease index for control (Tables 4 and 5). 162In the case of Fusarium wilt of rocket, in the presence of a disease incidence of 55 in the 163 inoculated and untreated plots, one week of soil solarization carried out at both sub-optimal and 164 optimal temperature regimes, lead to complete control (first crop) and almost complete 165 control(second crop) of the disease in the first ...

Phytophthora capsici, a pathogen causing crown and root rot of zucchini in southern Italy since the 1980s, has recently been observed in open field in northern Italy, causing severe losses. Since chemical control on zucchini is complicated by a limited availability of registered chemicals, as well as by the scalar harvest, a number of resistance inducers, organic amendments, biocontrol agents and fungicides were tested against P. capsici, under greenhouse conditions.Experiments were carried out at the nursery level, with different timing and number of applications. In the presence of a very high disease pressure, the best disease control was provided by mefenoxam, followed by the phosphite-based products, which acted as resistance inducers and also provided a positive effect on plant biomass. Acibenzolar-S-methyl, although effective, was sometimes phytotoxic. The biocontrol agents tested as well as the patented formulation of Brassica carinata defatted seed meals were not effective, providing results statistically similar to the untreated control. The efficacy of resistance inducers is interesting in view of their possible use in alternation with chemicals, or as stand-alone treatments in cultivation systems which do not adopt chemical control.

In vitro evaluation was carried out on seed samples of wild and cultivated rocket cultivars, most frequently grown in Italy, and obtained from farms affected by the leaf spot caused by Alternaria japonica in Piedmont and Lombardy during the fall of 2010. Twelve seed samples were collected and assayed for the presence of A. japonica. The pathogen was isolated only from not disinfected seeds. Among the two seed samples of cultivated rocket (Eruca vesicaria), only one was infected by A. japonica at a level of one infected seed out of 800. Four out of ten samples of wild (Diplotaxis tenuifolia) rocket seeds were contaminated by A. japonica with the highest level of infection detected in a single sample of 3 out of 800. All tested isolates of A. japonica obtained from seeds were pathogenic on both wild and cultivated rocket.

Experimental trials have been carried out in order to evaluate the efficacy of preventative treatments based on plant defense activator products, biocontrol agents, a microbial complex with arbuscular mycorrhizal fungi, and Brassica carinata pellets against Fusarium oxysporum f. sp. lactucae race 1 on lettuce and Fusarium oxysporum f. sp. raphani on cultivated rocket under greenhouse conditions. These products were compared with fungicides known for their ability to induce host resistance (phosethyl-Al and acibenzolar-S-methyl), and with azoxystrobin. Three and four applications of the tested products were carried out on lettuce and rocket seedlings grown in nursery conditions. Treated and untreated plants were transplanted into soil infested with Fusarium wilt agents to obtain an average disease severity (DS) of 65.6-69.2 and of 56.9-62.1 on the untreated lettuce and rocket plants, respectively. The best Fusarium wilt biocontrol was obtained after four 2 applications of Bacillus subtilis Qst713 and with the Glomas microbial complex (42 and 46.7%, efficacy, respectively). Brassica carinata pellets provided a consistent control when applied 14 days before the rocket and lettuce were transplanted into the infested soil. Acibenzolar-S-methyl, applied at 0.025 g/liter, showed a DS reduction in F. oxysporum f. sp. lactucae from 36 to 61% and of F. oxysporum f. sp. raphani from 54 to 73%, thus showing statistically similar results to those of azoxystrobin, which was used as a reference (DS reduction from 59 to 65%). Although the Fusarium wilt control provided by such products was not complete in the present experimental conditions, these products can be considered interesting components for an integrated pest management of the Fusarium wilt of leafy vegetables, starting from nursey applications. Moreover, the tested BCAs could become potentially useful, especially for plant monocultures. This study has been produced new information on the effects of potassium phosphite, applied at the nursery level, on reducing lettuce and rocket fusarium wilt. An average efficacy of 69.5% was observed for lettuce, while an average efficacy of 65.2% was observed for cultivated rocket. The good fungicidal activity of the phosphite-based product, coupled with the positive effect on plant biomass, is of special interest.