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The proliferation of weeds in agricultural fields competes directly with crops for essential resources such as, leading to reduced crop yields and economic profitability. The objective of this study was to evaluate the effect of weed management practices on dry bean productivity and economic profitability. Field experiments were conducted between 2018 and 2019 following a Randomized Complete Block Design with four replications and seven treatments. The treatments included: MW (Manual hoe weeding 21DAS), H1 (paraquat 3 l ha−1), H2 (acetochlor 3 l ha−1), H3 (atrazine 3 l ha−1), H1H2 (paraquat 1.5 l ha−1plus acetochlor 1.5 l ha−1), H1H3 (paraquat 1.5 l ha−1 plus atrazine 1.5 l ha−1) and H2H3 (atrazine 1.5 l ha−1 plus acetochlor 1.5 l ha−1). Dry seed yield obtained in 2018 were similar regardless of treatments. However, in 2019, among the herbicides, H1 induced the highest yield (1t ha−1), while the lowest (0.45 t ha−1) was recorded with H2. In addition, the decrease in yield under MW (0.86 t ha−1) was due to the high density of following species: Cynodon dactylon, Commelina benghalensis, Imperata cylindrica, Bidens pilosa, Euphorbia heterophylla and Euphorbia hirta. The economic analysis of treatments using the Ratio Cost Value (RVC > 1) classified them in descending order: MW > H1 > H2H3 > H3 > H1H3 > H2 > H1H2. However, when the cultivated area to be weeded is expanding and labor becomes scarce, the rains are regular and abundant, manual hoeing may become tedious. In this case, the application of 3 l ha−1 of paraquat becomes an alternative to manual hoeing for farmers wishing to increase dry bean seed production. [ABSTRACT FROM AUTHOR]

Primary Trans Chromosomal Tritipyrum (PTCT) amphiploid is a new cereal grown in saline soil and brackish water for grain and forage production. We evaluated the tolerance to seed deterioration in 13 promising PTCT lines, assessing accelerated aging (AA) tests by using AA boxes with 100% relative humidity at 40 °C for 72 h. The (Ma/b)(Cr/b)F4 and (St/b)(Cr/b)F4) PTCT lines, more sensitive to seed aging, were primed with NaCl, Salicylic Acid (SA), and Polyethylene Glycol (PEG) to increase the seed vigor of artificially aged seeds. Germination and emergence traits, biochemical parameters, and chromosomal abnormalities induced by artificial aging were measured in deteriorated and not-deteriorated seeds. The highest reduction percentages related to seed vigor were observed in (Ka/b)(Cr/b)F2 (34.52) and La(4B,4D)/b (28.15) lines, while the lowest was found in (Ma/b)(Cr/b)F4 (7.65) and (St/b)(Cr/b)F4 (7.46) lines. Seed aging also increases electrolytes, potassium, and protein leakages. Chromosomal abnormalities are caused by seed aging that interferes with chromosome behaviors during cell division. Seed priming on aged seeds revealed an increase in the germination percentage (GP) with PEG treatment, while the priming by SA showed an increase in seedling traits, such as the seedling length (SL2). In conclusion, we highlighted the potential use of different PTCT lines and the effective use of seed priming on deteriorated seed to enhance seed viability and seedling vigor as a useful tool for sustainable agriculture. [ABSTRACT FROM AUTHOR]

In recent decades, cereal agriculture across main producing areas in Spain has progressively adopted direct sowing, associated with an increased use of herbicides in pre-sowing. Weedy species from genus Avena have been observed after the application of glyphosate in wheat. Here, Avena fatua (two accessions), Avena byzantina and Avena sterilis subsp. sterilis, one accession each, were taxonomically characterized by a biometric study. Dose-response trials confirmed that one A. fatua accession evolved to resistance, because it was four times more resistant (R) than the others, ascribed as susceptible (S). In addition, based on LD50, A. byzantina and A. sterilis had low susceptibility to glyphosate, with 604 and 458 g ae ha−1. Shikimic acid accumulation was able to discriminate between high susceptible (A. fatua (S)), low susceptible (A. byzantina and A. sterilis), and low resistant (A. fatua (R)) populations. On the other hand, the study revealed that A. fatua (R), A. byzantina and A. sterilis had low foliar uptake and decreased movement of glyphosate. In addition, the metabolism study showed less metabolite accumulation in A. byzantina and A. fatua (S). However, at 96 h after glyphosate application, A. fatua (R) and A. sterilis were able to convert more than 30% of glyphosate to aminomethylphosphonic acid (AMPA) and sarcosine. Enzyme basal activity and I50 values predicted high affinity between the herbicide and the target enzyme for all accessions, thus indicating that a target-site (TS) mechanism is probably not involved in the differences in glyphosate susceptibility. In closing, non-target site (NTS) mechanisms could participate both in A. fatua R to glyphosate, and low susceptibility in A. byzantina and A. sterilis from Spain. [ABSTRACT FROM AUTHOR]

During the period 2021–2022 in the Institute of Forage Crops - Pleven was established the influence of pre-sowing treatment (priming) of seeds with Siliplant under laboratory conditions on the initial development of three varieties of alfalfa grown by conventional ("Dara" and "Pleven 6") and BSP5A001 biological method. Laboratory seed germination and primary plant development in vitro conditions and their response were evaluated using the complex plant growth index (GI) of the cultivars included in the study. It was established that the recommended working concentration for pre-sowing treatment of alfalfa seeds with Siliplant for field conditions is in the range of 0.5÷0.6%, determining a complex stimulating effect on the growth of the root, epicotyl, and seedling, respectively and on the initial development of alfalfa in the "sowing-emergence" period. By means of polynomial regression analysis, equivalence was established between stimulating and/or depressing effect on seedling growth as a result of the pre-sowing treatment of alfalfa seeds with Siliplant, expressed by the plant development index (GI). [ABSTRACT FROM AUTHOR]

In recent decades, cereal agriculture across main producing areas in Spain has progressively adopted direct sowing, associated with an increased use of herbicides in pre-sowing. Weedy species from genus Avena have been observed after the application of glyphosate in wheat. Here, Avena fatua (two accessions), Avena byzantina and Avena sterilis subsp. sterilis, one accession each, were taxonomically characterized by a biometric study. Dose-response trials confirmed that one A. fatua accession evolved to resistance, because it was four times more resistant (R) than the others, ascribed as susceptible (S). In addition, based on LD50, A. byzantina and A. sterilis had low susceptibility to glyphosate, with 604 and 458 g ae ha−1. Shikimic acid accumulation was able to discriminate between high susceptible (A. fatua (S)), low susceptible (A. byzantina and A. sterilis), and low resistant (A. fatua (R)) populations. On the other hand, the study revealed that A. fatua (R), A. byzantina and A. sterilis had low foliar uptake and decreased movement of glyphosate. In addition, the metabolism study showed less metabolite accumulation in A. byzantina and A. fatua (S). However, at 96 h after glyphosate application, A. fatua (R) and A. sterilis were able to convert more than 30% of glyphosate to aminomethylphosphonic acid (AMPA) and sarcosine. Enzyme basal activity and I50 values predicted high affinity between the herbicide and the target enzyme for all accessions, thus indicating that a target-site (TS) mechanism is probably not involved in the differences in glyphosate susceptibility. In closing, non-target site (NTS) mechanisms could participate both in A. fatua R to glyphosate, and low susceptibility in A. byzantina and A. sterilis from Spain.