Ninety-eight high-yielding recombinant inbred lines (RILs) of WAB638-1/PRIMAVERA rice were evaluated with the parents under reproductive stage drought stress. The study aimed at characterizing flowering time response under drought stress and consequently classifying the genetic resources for efficient use in breeding programmes. Two field trials were conducted during the 2016 and 2017 dry seasons using the randomized complete block design with two replications. In 2016, 12 RILs were evaluated with the parents for the rooting attributes under drought stress and well-watered treatments. Analysis of variance revealed a significant (P < 0.05) variation among the genotypes for the traits evaluated. Drought stress reduced most of the characters in this study, including grain yield. However, the inbred lines exhibited considerable tolerance to drought stress as indicated by yield-related stress indexes, including stress susceptibility and drought tolerance indexes. Delayed flowering (FD) was recorded in 75 genotypes (including WAB638-1), while 25 genotypes (including PRIMAVERA) had no delay under drought stress compared to the control. The genotypes were grouped into flowering delay (D) genotypes (FD > 1 d) and no delay (N) genotypes (FD < 1 d), which significantly differ (P ⩽ 0.05) for numbers of days to 50% flowering. The flowering delay genotypes may be suitable for intermittent drought, while genotypes with little or no delay may be selected for terminal drought conditions. There was a significant correlation (r > 0.5) between the root length and number of days to 50% flowering. The study indicated that root parameters, such as the root length, may contribute to the drought adaptation mechanisms of the RILs.

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.

Studying the evolutive and adaptative machanisms of prokayotes is a complicated task.As these machanisms cannot be easily studied "in vivo", it is necessary to consider other methods.We have therefore developed the RAevol model, a model designed to study the evolution of bacteria and their adaptationto the environment.Our model simulates the evolution of a population of artificial bacteria in a changing environment, providing us with an insight into the strategies that digital organisms develop to adapt to new conditions.In this paper we describe the principle and architecture of the model, focusing on the mechanisms of the regulatory networks of artificial organisms.Experiments were conducted on populations of artificial bacteria under conditions of stress.We study the ways in which organisms adapt to environmental changes and examine the strategies they adopt.An analysis of these adaptation strategies is presented and a brief overview was proposed concerning the patterns and topological characteristics of the evolved regulatory networks.