Industrialization and urbanization have led to an increased accumulation of waste materials that are transformed into a nutrient-rich and high-quality product called vermicompost by the vermicomposting process. Vermicomposting is an ecofriendly and economically favorable biotechnological process that involves the interaction of earthworms and microorganisms. Due to the importance of this process and its great potential in dealing with the consequences of waste accumulation, this review aims to provide key insights as well as highlight knowledge gaps. It is emphasized that there is a great challenge in understanding and clarifying the mechanisms involved in the vermicomposting process. The optimization of the factors affecting the possible application of vermicompost is crucial for obtaining the final product. Information on the composition of bacterial communities, amount of vermicompost, effect on heavy metal content, plant pathogens, diseases and organic waste selection is here recognized as currently the most important issues to be addressed. By answering these knowledge gaps, it is possible to enable wider utilization of vermicompost products.
Due to climate change in recent years, there has been an increasing water deficit during the winter wheat sowing period. This study evaluated six Croatian winter wheat varieties’ physiological, biochemical, and molecular responses under two drought stress levels at the germination/seedling growth stage. Lipid peroxidation was mainly induced under both drought stress treatments, while the antioxidative response was variety-specific. The most significant role in the antioxidative response had glutathione along with the ascorbate-glutathione pathway. Under drought stress, wheat seedlings responded in proline accumulation that was correlated with the P5CS gene expression. Expression of genes encoding dehydrins (DHN5, WZY2) was highly induced under the drought stress in all varieties, while genes encoding transcription factors were differentially regulated. Expression of DREB1 was upregulated under severe drought stress in most varieties, while the expression of WRKY2 was downregulated or revealed control levels. Different mechanisms were shown to contribute to the drought tolerance in different varieties, which was mainly associated with osmotic adjustment and dehydrins expression. Identifying different mechanisms in drought stress response would advance our understanding of the complex strategies contributing to wheat tolerance to drought in the early growth stage and could contribute to variety selection useful for developing new drought-tolerant varieties.