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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]

Propagation of wild fruit species is rare, somewhat difficult and necessitates for standardization for their conservation and uphold livelihood. Therefore, a trial was conducted on pre-sowing seed treatment to evaluate best treatment for germination of Dimocarpus longan Lour. (Sapindaceae) Falcourtia jangomas (Lour.) Raeusch. (Flacourtiaceae) and Myrica esculanta Buch. Ham. Ex. D. Don (Myricaceae) in the nursery of ICFRE- Rain Forest Research Institute, Sotai, Jorhat. The seed germination test was conducted in nursery bed filled with mixture of Soil and FYM at the ratio of 3:1. The study revealed that germination of seeds influenced by pre-sowing treatments. Among 6 pre-sowing seed treatments given for Dimocarpus longan, the highest germination percentage (80%) was obtained in cold water treatment for 24 hours and the lowest (26%) for the seed treated with 20% Suphuric acid (H2 So4 ) for 15 min. Likewise, amongst 7 pre sowing seeds treatments for Flacourtia jangomas, 80% germination was observed for the soaking treatment of 5% ethrel for 5 min, followed by Gibberellic acid (GA3 ) 800 ppm treatment for 18 hours was 63%. Among 6 different pre sowing seed treatments of Myrica esculenta, the 15 min soaking treatment with 20% H2 So4 was recorded for 30% germination, followed by 30% H2 So4 for 20 min was 20%. Observed that seeds of Dimocarpus longan were started germination on 9 day of sowing and completed within 30 days. Germination of Flacourtia jangomas seeds started on 45 day of sowing and completed within 90 days. The seed of Myrica esculenta was observed to germinate 6 months after sowing. [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]

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.

Context: Sorghum is a hosting plant of Melanaphis sacchari/sorghi. The control measures against the insect include the treatment of seeds. However, evaluation of the effect of insecticides on insect populations and the agronomic variables of the crop, are needed. Aim: To evaluate the influence of insecticides clothianidin, thiamethoxan, and imidacloprid during the treatment of hybrid 85 P15 (Pioneer®) seeds on the agronomic variables of the crop and infestation with M. sacchari/sorghi. Methods: The experiment was conducted in the School of Higher Studies in Xalostoc, Mexico, in 2018. Four doses of Poncho®, Cruiser® 5 FS, and Tools® TS in the treatment of hybrid 85 P15 (Pioneer®) seeds. A randomized block experimental design was applied, and the percentage of germination, M. sacchari/sorghi infestation, and agronomic parameters of the crop, were determined. Results: All the parameters achieved more than 90% of germination, which demonstrated that the products and doses did not affect this parameter. Likewise, no differences were observed in the treatments. The use of these insecticides in hybrid seeds had a little influence on aphid infestation. These treatments do not affect the content of chlorophyll, but other parameters, like Brix degree, and the fresh leaf weight were affected. Conclusions: The seed treatment does not reduce the percentage of germination of 85 P15 (Pioneer®) hybrids, a strong control was not achieved over infestation of aphids, but it did affect some agronomic variables; hence, evaluation of other hybrids is recommended.

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.

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]

Herbal medicines are in great demand for preliminary health care due to their wide medicinal value, with no side effects. Since many species are used in the system of traditional medicine, scientists have great opportunities to develop appropriate packages of practices for their multiplication and conservation. Abrus precatorius is the native plant of India and used in many ways in the Indian Ayurvedic system of medicine. This seeds of the species is dormant due to hard seed coat. So the aim of the study is to remove seed dormancy and enhance germination capacity within a short period. To overcome the problem of dormancy, seeds were scarified by seed scarifier and sand paper and also treated with acid (H2SO4) and hot water just before sowing. 60-95% germination was achieved under different treatment conditions while the seeds without any treatment fail to germinate. The highest (95%) germination was observed just 12 days after sowing in seeds treated with concentrated H2SO4 for 120 minutes. 70-75% germination was achieved when the seeds were treated with acid for 105 and 135 minutes. Seeds treated with con. H2SO4 for 150, 90 and 60 minutes and also scarified by sand paper showed similar results with 60-65% germination. The seeds scarified by a mechanical scarifier and treated with hot water did not show more than 32.5% germination.

Researchers have focused their efforts on the use of magnetic field as a pre-sowing method, as it is an inexpensive, environmentally friendly technique. This study provides a holistic approach of an agricultural cultivation that can lead to the comprehension of the exact mechanism of magnetic field effect on plant and lead to the appropriate application of magnetic fields. Pulsed electromagnetic field was used for 0, 15, 30 and 45 min as a pre-sowing treatment in durum wheat seeds in a field experiment for three years. The experiment followed a completely randomized design, with four treatments (Control, MF-15, MF-30 and MF-45), two cultivars and three replications. The aim of this study was to determine the effect of magnetic field exposure on durum wheat seeds, covering a complete range of agronomic characteristics. The results obtained in this three-year experiment showed a positive impact of pulsed electromagnetic field, in durum wheat cultivation. Magnetic field has been found to enhance germination, tillering, dry weight, leaf area, chlorophyll content, photosynthetic rate, transpiration rate, stomatal conductance and yield of two durum wheat cultivars. Duration of 30 and 45 min of pre-sowing magnetic field treatment gave the best results. Regarding yield measurement, all magnetic field treatments (MF-15, MF-30 and MF-45) gave statistically significantly higher values compared to control. In addition, α-amylase activity measurements showed that magnetic field affects enzymes and this could possibly explain the improved germination. [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]

Herbal medicines are in great demand for preliminary health care due to their wide medicinal value, with no side effects. Since many species are used in the system of traditional medicine, scientists have great opportunities to develop appropriate packages of practices for their multiplication and conservation. Abrus precatorius is the native plant of India and used in many ways in the Indian Ayurvedic system of medicine. This seeds of the species is dormant due to hard seed coat. So the aim of the study is to remove seed dormancy and enhance germination capacity within a short period. To overcome the problem of dormancy, seeds were scarified by seed scarifier and sand paper and also treated with acid (H2SO4) and hot water just before sowing. 60-95% germination was achieved under different treatment conditions while the seeds without any treatment fail to germinate. The highest (95%) germination was observed just 12 days after sowing in seeds treated with concentrated H2SO4 for 120 minutes. 70-75% germination was achieved when the seeds were treated with acid for 105 and 135 minutes. Seeds treated with con. H2SO4 for 150, 90 and 60 minutes and also scarified by sand paper showed similar results with 60-65% germination. The seeds scarified by a mechanical scarifier and treated with hot water did not show more than 32.5% germination. [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]

Abstract: Glyphosate is world-wide seen as the most widely used herbicide ingredient. In Germany, from 1999 to 2010, the use of glyphosate based herbicides (GBH) increased by 100%. Many agronomical benefits are attributed to glyphosate, but there is also public criticism. To analyse current application patterns and to assess the agronomical importance of GBH in Germany, a survey was carried out among 896 arable farmers. The survey took place in early 2011, taking 2009 as a reference year. In Germany, cultivation of transgenic crops is generally not permitted and, therefore, herbicide resistance trait does not play any role in application patterns. Based on farmer''s statements, a calculated application area of 4.3 million hectare arable land was estimated, representing 39% of total arable area. Three application modes receive major proportions of glyphosate use, these are: pre-sowing (20.7% of application area), pre-harvest (11.2%) and stubble application (68.1%). Among the field crops, oilseed rape (including oilseed rape stubbles) is treated with 27.5% of the nation-wide glyphosate amount followed by winter barley (20.1%) and winter wheat (15.8%). Without using glyphosate, farmers expect an increase in the share of ploughed arable land from 38.1% to 71.4%. Also, without glyphosate the use of cultivator on stubble land is expected to increase about 1.6 passes on average. If applied pre-sowing, glyphosate could save herbicide applications in the following crop. Saving one application of a post-emergence herbicide was estimated by farmers for corn and sugar beet (46% of pre-sowing applications), silage maize (40%), oilseed rape (27%), and winter wheat (22%). Most applications are applied on off-crop fields, so farmers did not quote any observation of yield savings due to glyphosate. The nation-wide economic benefit of glyphosate due to savings of other agricultural measures such as soil cultivation and post emergence herbicides is calculated between 79 and 202 million Euro per year, depending on glyphosate price. We conclude, that glyphosate offers large benefits to farmers, though some routine applications results in only moderate economic benefit compared to the non chemical practices being replaced. Developing decision rules for farmers might allow for an optimum allocation of glyphosate use. [Copyright &y& Elsevier]

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]

Abstract: Chemical control of weeds in seedbed sown onion (Allium cepa L. cv. Geza 20) and the effect of different herbicides on onion seedlings and weed growth were investigated in two field experiments conducted at the central Jordan Valley during the 1998/1999 growing season. Weed competition reduced average onion fresh yield by 62% compared with the weed-free control. Out of 14 herbicides tested in 16 treatments, oxadiazon at a dose of 0.75kgaiha−1 and oxyfluorfen at 0.6kgaiha−1, both applied as pre-sowing and post-emergence to onion seedlings resulted in the highest seedlings yield and the lowest weed biomass. Post-emergence application of both herbicides gave a similar yield of onion seedlings to that of the weed-free control. Paraquat at 20gaiha−1 significantly increased yield of onion seedlings over the weed-infested control and other herbicides tested. Many of the herbicides used including pronamid, prometryn, methabenzthiazuron, diphenamid, metribuzin and pyrazon were phytotoxic to seedbed sown onion in both sites and reduced seedlings growth and stand below the weed-infested control. Oxadiazon in pre-sowing and oxyfluorfen in post-emergence application were the best in controlling many “hard to kill” weeds including Chenopodium murale, Malva sylvestris, and Cyperus rotundus, and in increasing seedlings yield, while oxyfluorfen in a post-emergence application treatment was the best of all herbicides used. [Copyright &y& Elsevier]