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As the continuous demography registered during the last decades of the last century increases, the population on the Earth reached alarming levels due to the increasing needs of the population in continuous increase on the one hand and on the other hand, due to the human intervention in larger areas of the Earth. This continuously increased ominous anthropic influence, that attracts also the limitation of the planetary resources of all kinds, conducted during the last years to the unanimous recognition of the fact that the plants have the status of vital element within the world natural heritage, being a main element for maintaining the life on Earth and representing at the same time an essential resource for the future, for the planet existence (Convention on Biological Variety, 1992; The Declaration from Grand Canaria on World Program for Plants Preservation, 2000).

The use of high-performant varieties could help to improve the production of food legumes and thus meet the demand of the growing world population. However, long periods needed to develop new varieties through traditional breeding are a major obstacle. Thus, new techniques allowing faster genetic advance are needed. Speed breeding using longer periods of light exposure on plants, appears to be a good solution for accelerating plant life cycles and generation turnover. However, applying extended photoperiod causes plant stress and mortality due to lack of information on the adequate intensity to be used in speed breeding protocol. This study examines the impact of light intensity under speed breeding conditions on the development and growth of lentils and chickpeas, with a keen interest in enhancing genetic gain in these key food legumes. Four distinct levels of light intensity (T1: Green-house: 2000 µmol/m 2 /s; T2: 148-167 µmol/m 2 /s; T3: 111-129 µmol/m 2 /s; T4: 74-93 µmol/m 2 /s) under a photoperiod of 18 h of light and 6 h of darkness were tested in a growth chamber. Significant variation depending on light intensity was observed for plant height, total biomass, number of secondary stems, pods number, number of seeds per plant, growth rate, green canopy cover, time to flowering, time of pod set, time to maturity, vegetative stage length, reproduction stage length and seed filling stage length. Light intensity significantly influenced flowering/maturity and plant's stress compared to normal conditions in green-house where flowering/maturity were around 67/97 days for lentil and 79/111 days for chickpea. Therefore, lentils in treatment 2 flowered and reached maturity in 30/45 days respectively, with high stress, while chickpeas in the same treatment did not flower. In contrast, treatment 4 showed interesting results, promoting optimal growth with low stress, and flowering/maturity in 27/46 days and 28/54 days, respectively for lentils and chickpeas. These results underline the crucial importance of light management in speed breeding to accelerate vegetative growth and phenology while allowing healthy growth conditions for plants to produce enough seeds for generation turnover., (© 2024. The Author(s).)

Lentil is an important pulse that contributes to global food security and the sustainability of farming systems. Hence, it is important to increase the production of this crop, especially in the context of climate changes through plant breeding aiming at the development of high-yielding and climate-smart cultivars. However, conventional plant breeding approaches are time and resources consuming. Thus, speed breeding techniques enabling rapid generation turnover could help to accelerate the development of new varieties. The application of extended photoperiod prolonging the duration of the plant's exposure to light and shortening the duration of the dark phase is among the simplest speed breeding techniques. In this study, genetic variability response under extended photoperiod (22 h of light/2 h of dark at 25 °C) of a lentil collection of 80 landraces from diverse latitudinal origins low (0°-20°), medium (21°-40°) and high (41°-60°), was investigated. Significant genetic variations were observed between accessions, for time to flowering [40 → 120 days], time of pods set [45 → 130 days], time to maturity [64 → 150 days], harvest index [0 → 0.24], green canopy cover [0.39 → 5.62], seedling vigor [2 → 5], vegetative stage length [40 → 120 days], reproduction stage length [3 → 13 days], and seed filing stage length [6 → 25 days]. Overall, the accessions from Low latitudinal origin demonstrated a favorable response to the extended photoperiod application with almost all accessions flowered, while 18% and 57% of accessions originating from medium and high latitudinal areas, respectively, did not successfully reach the flowering stage. These results enhanced our understanding lentil responses to photoperiodism under controlled conditions and are expected to play important roles in speed breeding based on the application of the described protocol for lentil breeding programs in terms of choosing appropriate initial treatments such as vernalization depending on the origin of accession., (© 2024. The Author(s).)

The aim of this study was the phenotypic and genotypic analysis of the antibiotic resistance and virulence markers in enterobacterial strains isolated from the hospital environment. In this purpose, 100 enterobacterial strains isolated from hospital surfaces were investigated for their susceptibility patterns, for the ability to colonize the cellular (HeLa) and inert substrate and for the production of soluble, enzymatic factors. The bacterial strains were also investigated for the presence of resistance and virulence genes (aggR, aggA, EaggEC, EAST1, hlyA). The enterobacterial strains isolated from the hospital surfaces exhibited high levels resistance rates to beta-lactams, including 3'd generation cephalosporins, teteracyclines, sulphametoxazole and nalidixic acid. The PCR analysis demonstrated the presence of TEM1, tetA, tetB, tetC, dfrA12, sulI and sulII in a low percentage of the resistant strains. The majority of the tested strains exhibited ability to colonize the inert and cellular substrate and also the ability to produce a series of soluble enzymes implicated in enteric and extra-intestinal pathogenesis (pore forming enzymes, proteases, mucinases, iron chelating agents). The presence of beta-haemolysis on sheep blood agar was well correlated with the presence of hlyA gene, while the aggregative adherence pattern with the presence of aggA, aggR and EAST/1 genes, in different combinations. Our results are demonstrating that the E. coli strains isolated from the hospital environment harbor phenotypic and genetic virulence markers, thus contributing to the development of resistance and virulence genes reservoirs with potential implication for the human health in the hospital environment.