The American cranberry (Vaccinium macrocarpon Ait.) is a perspective and marketable crop both in Latvia and foreign markets, but berries are affected by rot in storage. The aim of the study was to detect the incidence level of cranberry fruit rot at the beginning of storage period in different places in Latvia. In 2007 - 2011, two hundred sound berries (out of 1000) were randomly collected by hand along a diagonal from five different cranberry plantations from locations all over Latvia. Berries were kept in plastic bags for a month and refrigerated at +7 °C. At the end of November, berries were sorted and rotten berries were separated from the sound ones. Over the period of 2007 - 2011, the incidence of storage rot reached 12 - 15% at the end of November, with an upwards trend observed every year, but the hot and rainy summer of 2010 significantly reduced the quality of fruit in storage, peaking on the average 33% of decayed berries. The incidence of fruit rot varied among the inspected cranberry plantations, but a tendency was observed that older plantations produced more rotting fruit and incidence of the disease was 12 - 50% after a month’s storage in the oldest plantation. The application of fungicides during the vegetation season did not affect development of post-harvest rot. Storage rot was a problem in the cranberry samples from all inspected plantations in Latvia, and in future the incidence of fruit rot is expected to increase.

Wheat crown rot is a harmful disease that can be caused by different pathogens. The control of this disease is complicated because of the diversity of pathogens and an insufficient efficacy of fungicides; therefore, the agronomic practices of wheat production are an important tool for reducing the disease development. The aim of this study was to estimate the incidence of wheat crown rot depending on soil tillage system and on the pre-crop of wheat in the year 2016. The field experiment was carried out at the Research and Study farm ‘Peterlauki’ of the Latvia University of Agriculture in the autumn of 2008. The data obtained in 2016 are analysed in this study: A – soil tillage system: 1 – traditional soil tillage with ploughing at the depth of 22 – 24 cm, 2 – reduced soil tillage with disc harrowing up to the depth of 10 cm; B – pre-crop of winter wheat: 1 – wheat, 2 – oilseed rape, 3 – faba beans. The incidence of crown rot was not influenced by soil tillage system, but the impact of pre-crop was significant (p = 0.006). The level of disease was essentially higher in continuous wheat sowings. The experiments showed that the main causal agents of the disease were Fusarium spp. and Oculimacula spp. The spectrum of pathogens was not dependent on a particular agronomic practice.

In this study, antifungal properties of an organoclay additive were investigated. Two types of organoclay (red and white) were tested in Petri dishes to determine their toxicity against the brown rot fungus Coniophora puteana and the white rot fungus Trametes versicolor. Red organoclay was more efficient than the white one and, depending on the fungus, inhibited or stopped the fungal growth. Red organoclay was chosen as an additive to produce a new type of plywood product. Biological durability of this plywood product was determined according to the methods: NF B 51-295 (bending strength test) and LVS ENV 12038:2002 (mass loss test). The loss in bending strength exceeded 81% and 65% after exposure to brown and white rot fungi, respectively. The mass loss of the plywood product after the decay test was higher than 3%, which defined the material as not fully resistant against decay fungi. According to CEN/TS 15083-1:2005, the plywood product corresponded to the durability class 3 (moderately durable) to 5 (not durable) depending on the fungus.

Japanese quince (Chaenomeles japonica) is cultivated as a fruit crop because its fruit possesses valuable properties. The total area of Japanese quince in Latvia is continuously increasing; therefore, fruit rot can become an important reason of yield loss. The aim of this study was to clarify the fruit rot incidence in Japanese quince plantations in Latvia and explore the influencing factors of rot development in the year 2017. The evaluation of fruit rot was carried out during the fruit development in eight places of different regions of Latvia where Japanese quince is grown commercially. Three plantations of different Japanese quince cultivars in Dobele and seven plantations where Japanese quince is grown from seedlings were observed. Fruit rot incidence among plantations had no significant differences. Statistically significant differences in fruit rot incidence depending on quince growth stage (p is less than 0.05) were found. Significant differences in fruit rot incidence were found between cultivars in Dobele.