Pbytopbtbora cactorum was isolated from necrotic stem lesions on 20-80% of diseased Betula pendula seedlings sampled from three nurseries in Finland. Fusarium avenaceum and Godronia sp. were also found in all nurseries. Inoculation of P. cactorum on B. pendula seedlings caused necrotic lesions and the spread of these lesions around the stem was detrimental. Neither the timing of N application nor two different PK-levels apphed to the seedhngs the previous year significantly affected the size of lesions caused by P. cactorum.

Fungi were isolated from the cone seales and seeds of Scots pine using plating on malt-extraet agar and/or the standard blotter method in a Jaeobsen's apparatus.Alternaria alternata, Epicoccum purpurascens and (jlocladium atrum were isolated from dampingoff seedlings germinating on agar or filter paper, but, in pathogenieity tests with peat-sand (1 :3) growth substrate, they were not pathogenic. All the Fusarium species isolated were pathogenic in growth substrate. Some E. avenaceum colonies formed no aerial hyphae and they provect to be a mixed eulture of the fungus, a fluorescent Pseudomonas sp., and a gram-negative bacterium. The bacterial associates appeared to inereasc the pathogenicity of F. avenaceum. All the micro-organisms tested were more pathogenie in sterilized than in unsterilized peat-sand substrate.

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Smartphone based visual assessment of vegetation cover is a promising, fast and repeatable approach that allows land managers to compare measurement on their farm with other farms. This study determined the influence of the smartphone device on green cover measurements on several crops. The hypothesis was that different smartphones would provide similar green cover (reflectance) for management purposes (i.e. < 10% difference).Forty fields in Finland were sampled between 10 and 28 July 2020 with Motorola Moto G7 and Samsung Galaxy A6 smartphones. The results were compared also to Sentinel-2 remote sensing of NDVI (Normalized Difference Vegetation Index) and biomass quadrants. The two smartphones had different green reflectance values that were correlated to each other.Both green reflectance measurements correlated with the normalized difference vegetation index (NDVI) that was measured with the Sentinel 2 satellite sensor and biomass. These finding suggest that smartphone-based monitoring can be used at least to classify vegetation to low, medium and high density, but that results from different cameras should not be compared.

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