Interference of weeds in vegetable crop cultivation, in the changing climate of Southern Europe with emphasis on drought and elevated temperatures: a review

Abstract

It is challenging to predict the changes in weed flora that may occur because of changes in global climate. Limited data are available on the effect of climate change and drought conditions on weed flora and their competitiveness in Southern Europe. Future predictions by scientists indicate reduced and untimely rainfall, along with increased temperatures in this region. Weeds possess a variety of developmental and physiological mechanisms, including senescing, increased leaf cuticular wax deposition, well-developed palisade parenchyma in the leaves, high root/shoot ratio, stomatal closure, peroxidase accumulation and symbiosis with endophytes that enable them to adapt to drought and high temperatures. Because of high adaptability of weeds to adverse environmental conditions, it can be assumed that under future warmer and drier environmental conditions, their growth will be favoured, while the competitiveness of vegetable crops against weeds will be decreased. It is important to highlight that the predicted decrease in overall rainfall levels throughout the year may lead to increased problems of herbicide residues (carryover effects) to following crops. The current paper provides an up-to-date overview of the adaptation mechanisms of weed species commonly found in Southern Europe, in order to expand the available knowledge regarding their response to drought and elevated temperatures. Emphasis is placed on revealing the effects of drought and increased temperatures on vegetable–weed competition and, most importantly, its effect on vegetable crop yield.

Seed oil and seed oil byproducts of common purslane (Portulaca oleracea L.): A new insight to plant-based sources rich in omega-3 fatty acids

“…Genetically modified and transgenic plants have been also suggested as potential sources of EPA and DHA in aquaculture to replace direct use of fish oils for fish feeding (Tocher, 2015;Tocher et al, 2019). However, climate change and competition of weeds with conventional crops under unfavorable conditions should be also considered and alternative crops resilient to environmental constraints could be an option for plant sources rich in omega-3 fatty acids (Karkanis, Ntatsi, Alemardan, Petropoulos, & Bilalis, 2019).…”

Addition of Phosphorus and Nitrogen Support the Invasiveness of Alternanthera Philoxeroides Under Water Stress

“…Moreover, environmental factors play a leading role either positively or negatively on the distribution of invasive species during the process of intrusion. [ 5,6 ] For example, a recent meta‐analysis comparing the growth performance of 74 invasive species with 117 native species to environmental changes has shown that the invasive species significantly benefited more from increased nutrient concentration. [ 7,8 ] However, these preceding studies considered only an individual component of environmental change rather than to manipulate the interrelating effects of multiple components of global change on invasions.…”

Relative success of frost-resistant variants of Avena fatua: a field experiment

“…Adaptation to environmental changes, and especially climate change, is a major concern which receives much attention from evolutionists to shape how the genetic complement of plant species can determine the future of the communities (Davis and Shaw, 2001;Franks et al, 2007;Hoffmann and Sgrò, 2011). Global warming and resulting drought determine the length of suitable growth periods, the photosynthetic efficiency and the triggering of plant reproduction (Patterson, 1995;Karkanis et al, 2018). It impacts weeds and the crop-weed interference at different scales as pointed out by Peters et al (2014): '(1) range shifts at the landscape scale, (2) niche (or crop) shifts at the community scale and (3) trait shifts of individual species at the population scale'.…”