The aim of the opening chapter of Agricultural Research Updates. Volume 27 is to discuss the role of phenolic compounds in the interactions of plants with abiotic stress, with special attention paid to their antioxidant properties. The second chapter attempts to assess the sustainability level of different types of agro-ecosystems in Bulgaria. A holistic hierarchical framework for measuring the integral, economic, social and ecological sustainability of agro-ecosystems in Bulgaria is proposed. Following this, a study is presented with the goal of identifying and evaluating social and economic sustainability indices in corn production. Statistical regression models were derived to estimate summer precipitation in a single location derived using lineal backward regression techniques, and the different efficiency between the derived models was analyzed. Next, an analytical Fourier series solution to the equation for heat transfer by conduction in a spherical shell with an internal stone consisting of insulating material is presented, and an internal heat source linearly reliant on temperature is considered as a model of conduction of heat in stone fruits. The subsequent study analyses the effects of certain parameters on the baking properties of wheat in years with different weather conditions. The results indicate statistically significant correlation coefficients between protein content, wet gluten content, alveograph properties, exstensograph properties and bread loaf volume. Lastly, a summary of recent knowledge is evaluated in order to contribute to a better understanding of how farming practices affect berry composition and consequently, the sensory characteristics of raspberries.