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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]

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]

Magnetic field is a variable abiotic factor, like temperature, air, soil and water that interacts with the living organisms. The use of different types of magnetic field at many different plant species is increasing and the results are promising. A two-year field experiment was established following a completely randomized design, to investigate the effect of pre-sowing magnetic field treatment for 0, 15, 30 and 45 min on three broad bean varieties. The obtained results showed that the treatment of seeds with pulsed electromagnetic field increased germination percentage, chlorophyll content, leaf area, photosynthetic rate, transpiration rate, stomatal conductance and dry weight. In general, the exposure of seeds for 15 min, gave the highest values compared to the control treatments for the three varieties used. A very interesting result is the fact that although there was an influence of the exposure of magnetic field on the dry weight of the plants, there was not a positive or a negative influence on the seed yield for both years. This means that magnetic field enhanced the vegetative development of the broad beans, but it had no effect on the reproductive development. The results indicate that magnetic field can be used in the cases that the productive direction of the cultivation of broad beans is for livestock forage and silage, as the pre-sowing treatment of seeds had a positive effect on plant dry weight. [ABSTRACT FROM AUTHOR]

This study describes seed germination and micropropagation of Senegalia nigrescens, an economic, medicinal and nitrogen-fixing species of South Africa. Seeds of S. nigrescens were subjected to pre-sowing treatments including soaking in cold water for 24 h, sulphuric acid (H2SO4) or hydrochloric acid (HCl) for 4, 8 and 12 min and mechanically scarifying seeds before sowing on Petri plates with wet filter paper. Mechanically-scarified seeds were also sown aseptically on a filter paper bridge, plain agar, ½ or full strength Murashige and Skoog (MS) basal medium. Single nodal explants from MS-derived seedlings were grown on MS media supplemented with 0.0, 0.5, 1.0 and 2.0 mg L−1 of benzylaminopurine (BAP) or kinetin (KIN) and a combination of 0.5 mg L−1 of BAP and KIN to investigate shoot multiplication. No significant differences were observed in the number of shoots produced across all treatments. However, the treatment containing 1.0 mg L−1 KIN produced a significantly higher shoot length (14.17 ± 5.20 mm) than 0.5, 1.0 and 2.0 mg L−1 BAP (7.67 ± 3.87, 6.75 ± 2.93 and 8.70 ± 3.56 mm, respectively). The highest rooting rate (16.7%) was obtained on ¼ strength MS supplemented with either indole-3-acetic acid (IAA) or indole-3-butyric acid (IBA) at concentrations 1.0 and 0.5 mg L−1, respectively. Rooted plantlets were successfully acclimatised with a 66.7% survival rate. The findings from this study would be of great benefit for the commercial propagation of S. nigrescens. [ABSTRACT FROM AUTHOR]

A field experiment was carried out at Tag Al EZZ Agricultural Research Station, ARC, Egypt (31°36'N/30°57'E) in two seasons of 2014-2015. This work aimed at assessing the effect of cultivating seeds treated with aerated solution of Salicylic Acid (SA) 1.00, 1.50, 2.00, 2.50 and 3.00 mM of 3 plants: kenaf (Hibiscus canabienus), sunflower (Helianthus annuus) and canola (Brassica napus) in phyto-remediating (bioreclamination) of a saline soil. Growth of plants (its seeds were presowing treated with salicylic acid) was higher than that of plants its seeds were not treated with the acid. The treatment induced tolerance to salt stress leading to promoting protective reactions to the photosynthetic pigments, maintained the membranes integrity and osmotic adjustment This increased growth led to removal of greater amounts of salts from the soil. Salinity as well as sodicity of the soil where treated plants were grown was lower than in soils where non-treated plants were grown. The 3.00 mM treatment was the most effective. [ABSTRACT FROM AUTHOR]

The present study was carried out to investigate the effect of pre-sowing treatments and environments on seed germination and seedling growth of guava (Psidium guajava L.). The study revealed that pre-soaking of guava seeds in hydrochloric acid (10%) for 2 minutes resulted in maximum seed germination percentage (54.16%). Scraping of seed coat with sand paper + soaking seeds in GA3 50 ppm for 24 hours has enhanced the seedling height (14.02 cm), stem girth (0.26 cm), number of leaves per seedling (15.24) and leaf area (3.38 cm2) while highest root length (6.56 cm) of seedlings were found in scraping of seed coat with sand paper + soaking seeds in GA3 100 ppm for 24 hours. All the germination and growth parameters were found to be the best in protected environment (viz., polyhouse) as compared to open field condition. Sowing of seeds without pre-sowing treatments showed poor results for all parameters. [ABSTRACT FROM AUTHOR]

Pre-sowing treatment of pulsed electromagnetic fields was used in corn seeds, in both indoor and outdoor conditions, in order to investigate the effect on plant growth and yield. The results of this research showed that pulsed electromagnetic fields can enhance plant characteristics, both under controlled environmental conditions and uncontrolled field conditions. The two varieties responded differently in the duration of magnetic field. Seeds were treated for 0, 15, 30, and 45 min with pulsed electromagnetic field ( MF-0, MF-15, MF-30, and MF-45). Common corn variety performed better results in MF-30 treatment, while sweet corn variety performed better in MF-45 treatment. Magnetic field improved germination percentage, vigor, chlorophyll content, leaf area, plant fresh and dry weight, and finally yields. In the very interesting measurement of yield, seeds that have been exposed to magnetic field for 30 and 45 min have been found to perform the best results with no statistical differences among them. Another interesting finding was in root dry weight measurements, where magnetic field has a negative impact in MF-30 treatment in both hybrids, however without affecting other measurements. Enhancements on plant characteristics with economic impact on producer's income could be the future of a modern, organic, and sustainable agriculture. [ABSTRACT FROM AUTHOR]

Two different pre-sowing techniques have been investigated for their influence in an important industrial plant, namely cotton. Priming methods are very useful for agricultural practices because they improve crop seedling establishment, especially when environmental conditions are not optimum. Pulsed electromagnetic fields have been found to promote germination and improve early growth characteristics of cotton seedlings. Such priming techniques are especially valuable in organic cultivation, where chemical compounds are prohibited. PEG treatment showed an enhancement in some measurements, however in some cases the results were not statistically different compared to control plants. In addition, PEG treatment is a sophisticated method that is far from agricultural practices and farmers. In this research, two different ages of seeds were used (1- and 2-year-old) in order to investigate the promotory effects of priming techniques. Magnetic field treatment of 15 min was found to stimulate germination percentage and to promote seeds, resulting in 85% higher values than control seeds under real field conditions. Furthermore, seeds that were treated with magnetic field performed better in terms of early-stage measurements and root characteristics. [ABSTRACT FROM AUTHOR]