Wheat Pest Dynamics, Forecasting and Current Importance of the Attack, to Develop Integrated Control System in the Center of Transylvania (ARDS Turda, 2006-2016)

Abstract

The paper presents data about wheat pest attack in Transylvania in the last 10 years, under the different climatic, phenological and technological conditions, with details of the correlations of the climatic factors with the bio-ecology of the species or pest groups. Such data may be important for modelling and forecasting wheat pest attacks. The climatic warming, represented strong environmental factors (R2 = 0.43), which led to changes in the species structure, favouring the development of the populations of a narrow spectrum of species becoming dominant and dangerous by numerical increases. In the years 2006-2015, the eudominance of thrips (58%), the dominance of aphids (14%) and of wheat flies (12%), the subdominant species of Chrysomelidae and the increase of entomophagus abundance were revealed. In the year 2016, the weight of the dominant groups of wheat flies (25%), aphids (21%), leafhoppers (18%), thrips (17%), of the subdominant group of Chrysomelidae (10.6%) and cereal bugs (4.5%) increased. Changes in entomocenotic interactions phytophagusentomophagus, changes in pest dynamics, and of optimal moments for treatments important in the development of integrated pest control systems, have occurred in wheat crops. In the conditions of the area, the annual abundance of entomophagus is determined by the annual abundance of phytophagous insects, as expressed by a positive correlation (R2 = 0.464 and D% = 46.4%). Under the conditions of the last 10 years, the annual ratio of the number of phytophagous / entomophagus fluctuated between 2.35 and 12.42. The size of the phytophagous / entomophagus ratio was strongly correlated with the increase of the average annual temperatures, with a percentage determination coefficient D% = 15.5%, having an optimum of the interactions at values of 6.3 phytophagous / 1 entomophagus, and less well correlated with the annual precipitations. These changes in wheat entomocenoses, the biological potential accumulated over the last 10 years and at the level of 2016 indicate the importance of adapting pest control strategies, which should include preventive methods (respecting the optimum sowing time, agro-technical and phytosanitary methods), insecticide treatments on seed and on vegetation, at optimal application times for the groups of pests whose attacks overlap, respectively the first treatment in the spring, no later than the end of tillering, for wheat flies, leafhoppers, Chrysomelidae etc.; the second treatment at the phenophase of flag leaf stage and ear appearance, for thrips, aphids, bugs etc.; and other treatments at warning. Given the importance of entomophagous arthropod fauna in limiting wheat pests it is necessary to protect and use the auxiliary entomophagus, flora biodiversity involved in achieving the productivity and stability of wheat crops.

Expert-Based Assessment of the Potential of Agroforestry Systems in Plain Regions across Bihor County, Western Romania

“…These combinations of agricultural crops and forest plantations generate a broad range of benefits, such as: the development of rural communities and farms due to a sustainable production and livelihood improvement [29][30][31][32][33], increased biodiversity and biological control of the pests [34,35], improved and healthier soils [36,37], food production [38,39], carbon sequestration [1,40] and a veritable strategy to fight against changing climatic conditions. It was recently reported [41] that most of these benefits could be also provided by promoting agroecology techniques.…”