Pesticides and Phytomedicine / Pesticidi i fitomedicina

Sclerotinia species in Serbia and possibilities of their control

Milica Mihajlović — 2023-12-29

Sclerotinia species are economically important, necrotrophic and aggressive plant

pathogens with a broad host range and worldwide distribution. They act as airborne or

soilborne pathogens, and can be transmitted by seed. These pathogens can affect crops

both during the growing season and after harvest. Yield losses due to Sclerotinia diseases

in susceptible crops vary and may be as high as 100%. The most common pathogen from

the genus Sclerotinia in Serbia is S. sclerotiorum. It occurs regularly on sunflower and its

incidence may exceed 50% in some years, thus causing economically important crop losses

in Vojvodina. Recently, two new species were detected in Serbia: S. trifolium in alfalfa and

S. minor in lettuce plants. Diseases caused by Sclerotinia spp. are difficult to control due to

the long-term survival of sclerotia in the soil and development of airborne ascospores. As

with many other diseases, there is no single treatment that can completely control these

pathogens. Implementation of multiple strategies, such as cultural practices (sanitation, crop

rotation and tillage), physical, chemical and biological protection, as well as deployment of

resistant cultivars, is necessary for effective disease management.

The effects of medium nutritional profile on Bacillus sp. Par 3 plant-growth promoting and biocontrol activity against Botrytis cinerea

Tatjana Dujković — 2023-12-29

Substantial agricultural losses resulting from plant diseases caused by different plant pathogens are one of the worldwide challenges today. Among these, Botrytis cinerea, responsible for gray mold disease, stands out for its capacity to devastate significant quantities of diverse valuable crops. Utilization of biocontrol agents for suppressing phytopathogens has become imperative, and bacteria from the genus Bacillus hold an immense potential due to their rapid replication rate, resistance to adverse environmental conditions, enhanced effectiveness in promoting plant growth and broad-spectrum activity. The objective of this study was to determine the best sources of carbon, nitrogen and phosphorus in cultivation media with the aim of maximizing both antimicrobial activity against B. cinerea and plant growth-promoting (PGP) potential during the early stages of cucumber plant development, exhibited by Bacillus sp. isolate Par 3. Antimicrobial activity was tested using the well diffusion method. The influence of Bacillus sp. isolate Par 3 on plant germination was tested on cucumber seeds. The largest inhibition zones were achieved in two cases, with 1) sucrose as carbon source, ammonium nitrate as nitrogen source, and diammonium hydrogen phosphate as phosphorus source and 2) glycerol as carbon source, ammonium nitrate as nitrogen source and dipotassium hydrogen phosphate as phosphorus source. Seeds treated with a culture liquid of Bacillus sp. isolate Par 3 using the optimized medium exhibited the best results in terms of cucumber germination percentage (100%), root length (53.09 mm) and shoot length (13.26 mm). Bacillus sp. Par 3 isolate was identified as Bacillus subtilis using 16S rRNA gene sequencing. The results of this study underscore the significance of media optimization for the production of biocontrol agents, taking into account both antimicrobial efficacy and PGP characteristics.

Impact of neem cake amendment in the casing soil on control of Trichoderma aggressivum Samuels & W. Gams and Lycoriella ingenua (Dufour) and mushroom yield

Tanja Drobnjaković — 2023-12-29

The study was focused on improvement of the integrated management strategy against green mould disease agent Trichoderma aggressivum Samuels & Gams and mushroom fly Lycoriella ingenua (Dufour) as pests of the white button mushroom Agaricus bisporus (Lange) Imbach. The impact of neem cake amendment in casing soil on regulation of the abundance of mushroom sciarid fly adults, efficacy in controlling the green mould disease agent, and mushroom yield was evaluated. Casing soil was supplemented with different concentrations of neem cake: 1, 2.5, 5, 10 and 15%. Neem cake added as a supplement to casing soil at a rate of 2.5% reduced the number of mushroom fly adults by 83.93% and green mould disease incidence by 59.6% in comparison to the control. No adverse effect on mushroom formation, yield and quality of fruiting bodies was observed at that concentration. Amendment of 2.5% neem cake in the casing soil could be recommended for application in mushroom production to control L. ingenua and symptoms of green mould disease without negative impact on mushroom yield.

Species of the genus Parthenolecanium (Hemiptera: Coccidae) in urban environments in Serbia

Marina Dervišević — 2023-12-29

Four species of soft scales from the genus Parthenolecanium have been registered in urban areas in Serbia: Parthenolecanium corni, P. fletcheri, P. pomeranicum, and P. rufulum. They all develop one generation annually and overwinter as second-instar nymphs on host twigs. P. corni reproduces by gamogenesis, while the other three species reproduce by parthenogenesis. The species were recorded on the territory of Serbia in 22 locations on 20 host plants, whereby P. corni was identified on 8 new host plants, and P. fletheri on one new host. The intensity of scale attacks and damage symptoms on the infested plants were variable. P. corni, P. fletcheri, and P. rufulum formed numerous colonies on some woody and bushy plants, causing branches of individual plants to dry and decay.

Corrigendum to "Sensitivity of Cuscuta species and their hosts to Anethum graveolens essential oil"

Marija Sarić-Krsmanović — 2023-12-29

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