scholarly journals Thermal inactivation of weed seeds and tubers during drying of pig manure.

1992 ◽  
Vol 40 (1) ◽  
pp. 11-19
Author(s):  
C.M.J. Bloemhard ◽  
M.W.M.F. Arts ◽  
P.C. Scheepens ◽  
A.G. Elema
Keyword(s):  
Thermal Inactivation ◽  
Chenopodium Album ◽  
Amaranthus Retroflexus ◽  
Solanum Nigrum ◽  
Abutilon Theophrasti ◽  
Pig Manure ◽  
Pig Slurry ◽  
Cyperus Esculentus ◽  
Sensitive Species ◽  
Industrial Processing

Propagules of 7 plant species were subjected to heat treatments comparable to industrial processing. Propagules of all species, which had been preincubated 1 day in pig slurry, responded to heat treatment in an oven in the range from 50 to 104 degrees C. Brassica napus and Solanum nigrum were the most heat-sensitive species. The viability of their seeds was greatly reduced after 15 min at 50 degrees C. Seeds of Amaranthus retroflexus, B. napus, Chenopodium album and S. nigrum were inactivated after 3 min at 75 degrees C, seeds of Echinochloa crus-galli and tubers of Cyperus esculentus after 3 min at 90 degrees , whereas seeds of Abutilon theophrasti only slightly responded to 3 min at 104 degrees . Heating seeds of A. theophrasti at 104 degrees with steam resulted in much less viability than heating at the same temperature in the oven. More than 1 day preincubation in slurry positively affected thermal inactivation of E. crus-galli seeds and C. esculentus tubers at 75 degrees , but not of A. theophrasti seeds at 75, 90, and 104 degrees . (Abstract retrieved from CAB Abstracts by CABI’s permission)

Comparison of the Photosynthetic Capacity between Intact Leaves of Triazine-Resistant and -Susceptible Biotypes of Six Weed Species

1984 ◽  
Vol 39 (5) ◽  
pp. 440-442 ◽  
Author(s):  
J.L.P. van Oorschot ◽  
P.H. van Leeuwen
Keyword(s):  
Photosynthetic Capacity ◽  
Chenopodium Album ◽  
Amaranthus Retroflexus ◽  
Solanum Nigrum ◽  
Poa Annua ◽  
Weed Species ◽  
Stellaria Media ◽  
Rate Of Photosynthesis ◽  
Intact Leaves ◽  
Polygonum Lapathifolium

The rate of photosynthesis in intact leaves of a triazine-resistant biotype of Amaranthus retroflexus was about 15% lower than that of a triazine-susceptible biotype. Differences in photosynthesis between resistant and susceptible biotypes of Polygonum lapathifolium, Poa annua and Solanum nigrum were not significant, and absent in Chenopodium album and Stellaria media. The results are brought in relation to the appearance of resistant biotypes in the field.

The Interaction of Acifluorfen and Bentazon in Herbicidal Combinations

Weed Science ◽  
1987 ◽  
Vol 35 (4) ◽  
pp. 449-456 ◽  
Author(s):  
Veldon M. Sorensen ◽  
W. F. Meggitt ◽  
Donald Penner
Keyword(s):  
Droplet Size ◽  
Chenopodium Album ◽  
Datura Stramonium ◽  
Amaranthus Retroflexus ◽  
Abutilon Theophrasti ◽  
Common Lambsquarters ◽  
Nitrobenzoic Acid ◽  
Redroot Pigweed

Acifluorfen {5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid} and bentazon [3-(1-methylethyl)-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide] were applied singly, in combination at various rates, with and without a crop oil concentrate to common lambsquarters (Chenopodium albumL. # CHEAL), redroot pigweed (Amaranthus retroflexusL. # AMARE), jimsonweed (Datura stramoniumL. # DATST), and velvetleaf (Abutilon theophrastiMedic. # ABUTH) grown in containers in the greenhouse and outdoors. Without crop oil concentrate, synergistic responses to the combinations were measured in common lambsquarters and velvetleaf. Antagonistic responses were measured in jimsonweed. Redroot pigweed response was antagonistic in the greenhouse and synergistic outdoors. The addition of a crop oil concentrate tended to mask the interactions. Crop oil concentrate also increased the droplet size for common lambsquarters, velvetleaf, jimsonweed, and redroot pigweed 53, 41, 28, and 27%, respectively. Neither herbicide at any rate or combination influenced droplet size. Radiolabeled studies showed reduced uptake of14C-acifluorfen when bentazon was present in common lambsquarters and redroot pigweed by 15 and 10%, respectively. Radiolabeled bentazon uptake was reduced 3% in jimsonweed and increased 20% in redroot pigweed when acifluorfen was present.

Weed control andZea maystolerance as affected by timing of RP-201772 application

Weed Science ◽  
1999 ◽  
Vol 47 (4) ◽  
pp. 375-382 ◽  
Author(s):  
Christy L. Sprague ◽  
Donald Penner ◽  
James J. Kells
Keyword(s):  
Zea Mays ◽  
Chenopodium Album ◽  
Field Studies ◽  
Amaranthus Retroflexus ◽  
Ambrosia Artemisiifolia ◽  
Abutilon Theophrasti ◽  
Physiological Basis ◽  
Setaria Faberi ◽  
Spray Solution ◽  
Herbicide Treatments

Field studies were conducted in 1996 and 1997 to determine the effects of RP-201772 and RP-201772 tank mixtures applied to emergedZea mays.RP-201772 at 105 g ha−1and tank-mixed metolachlor/benoxacor or atrazine were applied preemergence and to spike, 2-leaf, and 4-leafZ. mays.Herbicide treatments over the four application timings provided greater than 90%Chenopodium album, Ambrosia artemisiifolia, Amaranthus retroflexus, andAbutilon theophrasticontrol. However,Setaria fabericontrol varied among years and application timings. SevereZ. maysinjury, 70% and 40%, was observed when RP-201772 tank-mixed with metolachlor/benoxacor was applied to 2-leaf and 4-leafZ. mays, respectively. Greenhouse studies confirmedZ. mayssensitivity from delayed applications of RP-201772 tank-mixed with metolachlor/benoxacor. Similarly, increasedZ. maysinjury was observed from postemergence applications of RP-201772 tank-mixed with acetochlor/MON-13900. Herbicide absorption, translocation, metabolism, and retention studies were conducted to determine the physiological basis for the observedZ. maysinjury from delayed applications of the RP-201772 tank mixture with metolachlor/benoxacor. Metolachlor/benoxacor increased radiolabeled RP-201772 absorption when applied to spike, 2-leaf, and 4-leafZ. mays.RP-201772 translocation and metabolism did not explain enhancedZ. maysinjury. However, RP-201772 retention increased fivefold when metolachlor/benoxacor was present in the spray solution and applied to 2-leaf and 4-leafZ. mays.Increased RP-201772 absorption and retention appeared to be the basis forZ. maysinjury when tank-mixed with metolachlor/benoxacor and applied to emergedZ. mays.

scholarly journals Transmission of Tomato chlorosis virus (ToCV) by Bemisia tabaci Biotype Q and Evaluation of Four Weed Species as Viral Sources

Plant Disease ◽  
2016 ◽  
Vol 100 (10) ◽  
pp. 2043-2049 ◽  
Author(s):  
C. G. Orfanidou ◽  
P. G. Pappi ◽  
K. E. Efthimiou ◽  
N. I. Katis ◽  
V. I. Maliogka
Keyword(s):  
Bemisia Tabaci ◽  
Chenopodium Album ◽  
Amaranthus Retroflexus ◽  
Solanum Nigrum ◽  
Virus Concentration ◽  
Weed Species ◽  
Sonchus Oleraceus ◽  
Transmission Parameters ◽  
Arable Weeds ◽  
Tomato Chlorosis Virus

Tomato chlorosis virus (ToCV) is implicated in tomato yellows disease in many countries worldwide. It has a wide host range, including cultivated species as well as arable weeds, and it is transmitted in a semipersistent manner by at least five whitefly species or biotypes of the genera Trialeurodes and Bemisia. ToCV is not seed transmitted and more than 36 weed species have been recorded as natural reservoirs, acting as unique sources both for the virus and its vectors when susceptible crops are harvested. In this study, experiments were conducted to determine the transmission parameters of ToCV by biotype Q, the most abundant biotype of Bemisia tabaci in Greece. Results showed that biotype Q is an efficient vector of ToCV and it is able to retain the virus for at least 6 days. This vector was then used for the evaluation of four widespread weed species (Solanum nigrum, Sonchus oleraceus, Amaranthus retroflexus, and Chenopodium album) as ToCV sources through transmission experiments. Solanum nigrum was shown to be the most significant viral source among the tested weeds, followed by Sonchus oleraceus, A. retroflexus, and, lastly, C. album. Nevertheless, none of them was as efficient a ToCV source as tomato. This variation could be attributed to differences in virus concentration in each plant species or possible host preference by the whitefly vector.

Επίδραση της άρδευσης και της χλωρής λίπανσης στη ζιζανιοχλωρίδα

2007 ◽  
Author(s):  
Ανέστης Καρκάνης
Keyword(s):  
Datura Stramonium ◽  
Amaranthus Retroflexus ◽  
Solanum Nigrum ◽  
Abutilon Theophrasti ◽  
Portulaca Oleracea ◽  
Xanthium Strumarium ◽  
Hibiscus Trionum ◽  
Orobanche Ramosa ◽  
Setaria Glauca

Σκοπός της διδακτορικής διατριβής ήταν η μελέτη της επίδρασης της άρδευσης και της χλωρής λίπανσης στην ζιζανιοχλωρίδα. Σε πείραμα που πραγματοποιήθηκε σε φυτοδοχεία μελετήθηκε η επίδραση της άρδευσης στην ανάπτυξη και τα φυσιολογικά χαρακτηριστικά των ζιζανίων αγριοβαμβακιάς (Abutilon theophrasti), αγριομελιτζάνας (Xanthium strumarium), στύφνου (Solanum nigrum) και τάτουλα (Datura stramonium). Οι μεγαλύτερες τιμές του ξηρού βάρους, της αγωγιμότητας των στοματίων, του ρυθμού διαπνοής και του ρυθμού φωτοσύνθεσης των ζιζανίων καταγράφηκε σε επαρκώς αρδευόμενα φυτά. Σε πειράματα αγρού μελετήθηκε η ικανότητα ανταγωνισμού του βίκου αλλά και του λειμώνιου τριφυλλιού. Τα πειράματα πραγματοποιήθηκαν τα έτη 2005 και 2006, στον Δομοκό και στον αγρό του εργαστηρίου Γεωργίας. Παρατηρήθηκε ότι ο βίκος είναι πιο ανταγωνιστικός στα ζιζάνια σε σχέση με το λειμώνιο τριφύλλι. Επιπλέον το λειμώνιο τριφύλλι παρουσίασε μεγαλύτερη ικανότητα ανταγωνισμού στην Επαρχία Δομοκού. Επίσης σε πειράματα αγρού μελετήθηκε η επίδραση της χλωρής λίπανσης και των συστημάτων άρδευσης στην ζιζανιοχλωρίδα, σε καλλιέργεια καπνού. Τα πειράματα πραγματοποιήθηκαν τα έτη 2005 και 2006, στον Δομοκό και στον αγρό του εργαστηρίου Γεωργίας. Ακολουθήθηκε το πειραματικό σχέδιο των υποδιαιρεμένων τεμαχίων με 4 επαναλήψεις, δύο κύρια τεμάχια (σύστημα στάγδην άρδευσης και σύστημα καταιονισμού) και τρία υποτεμάχια (βίκος ως χλωρή λίπανση, λειμώνιο τριφύλλι ως χλωρής λίπανση και μάρτυρας (χωρίς λίπανση)). Ο μικρότερος αριθμός και το ξηρό βάρος των ζιζανίων καταγράφηκε στο σύστημα της στάγδην άρδευσης. Επίσης παρατηρήθηκε ότι ενσωμάτωση βιομάζας λειμώνιου τριφυλλιού της τάξης των 400Kg/στρέμμα (ξηρό βάρος) ήταν αρκετή ώστε να περιόρισα το φύτρωμα και την ανάπτυξη των ζιζανίων για χρονικό διάστημα 30 ημερών από την μεταφύτευση. Ακόμη ο μικρότερος αριθμός και ξηρό βάρος της οροβάγχης (Orobanche ramosa) καταγράφηκε στο σύστημα της στάγδην άρδευσης. Επίσης καταγράφηκε θετική συσχέτιση (R²=0.97; p=0.001) μεταξύ της ποσότητας του νερού άρδευσης και του αριθμού των φυτών της οροβάγχης. Ακόμη οι μεγαλύτερες τιμές της αγωγιμότητας των στοματίων, του ρυθμού διαπνοής και του ρυθμού φωτοσύνθεσης των σημαντικότερων ζιζανίων (Amaranthus retroflexus, Solanum nigrum, Convolovulus arvensis, Datura stramonium, Echinochloa crus-galli, Portulaca oleracea, Hibiscus trionum, Setaria glauca) καταγραφηκαν στα τεμάχια όπου έγινε χλωρή λίπανση με βίκο. Επίσης στις περισσότερες μετρήσεις οι μεγαλύτερες τιμές της αγωγιμότητας των στοματίων και του ρυθμού φωτοσύνθεσης καταγράφηκαν στα τεμάχια της στάγδην άρδευσης. Δεν παρατηρήθηκαν στατιστικά σημαντικές διαφορές για την θερμοκρασία των φύλλων των ζιζανίων μεταξύ των συστημάτων άρδευσης. Επιπρόσθετα το τραχύ βλήτο παρουσίασε τους μεγαλύτερους ρυθμούς φωτοσύνθεσης από όλα τα ζιζάνια. Τέλος στην αντράκλα, την σετάρια και την μουχρίτσα καταγράφηκαν οι μικρότερες τιμές της αγωγιμότητας των στοματίων.

scholarly journals Evaluation of Broadleaf Weeds Control with Selectivity of Post-Emergence Herbicides in Sugar Beet (Beta vulgaris L.)

2014 ◽  
Vol 6 (4) ◽  
pp. 491-497
Author(s):  
Ali Asghar CHITBAND ◽  
Reza GHORBANI ◽  
Mohammad Hassan RASHED MOHASSEL ◽  
Majid ABBASPOOR ◽  
Rahmat ABBASI
Keyword(s):  
Sugar Beet ◽  
Chenopodium Album ◽  
Dry Weight ◽  
Amaranthus Retroflexus ◽  
Solanum Nigrum ◽  
Portulaca Oleracea ◽  
Response Curves ◽  
Main Research ◽  
Significant Difference ◽  
Weeds Control

The reduction of herbicide applications is a main research priority in recent years. In order to study the effect of individual post-emergence application of sugar beet broad-leaf herbicides at four to six true-leaf stage of weeds, experiments were conducted during 2013. Treatments included untreated control and several rates of desmedipham + phenmedipham + ethofumesate, chloridazon and clopyralid on Portulaca oleracea, Solanum nigrum, Amaranthus retroflexus and Chenopodium album. A completely randomized layout with three replications was used for each herbicide. Three weeks after spraying (WAS), plants were harvested and measured their dry weight. These herbicides were more effective to control Portulaca oleracea than other weeds, thereupon minimum dose required for a satisfactory efficacy of 90% reduction of Portulaca oleracea aboveground dry matter (ED90) were 299.22, 1138.31 and 129.44 g a.i ha-1 of desmedipham + phenmedipham + ethofumesate, chloridazon and clopyralid, respectively. Solanum nigrum was more affected by clopyralid application (132.40 g a.i ha-1), and did not make significant difference in Portulaca oleracea. Chloridazon had lower effect for control of Chenopodium album due to existence of powdery covering on abaxial side of the leaves. Biomass ED50 or ED90, based on log-logistic dose–response curves, for Chenopodium album was considerably higher than other species. These results showed that tank mixtures with other herbicides may be required for satisfactory weed control and reduction in applied herbicides doses.

scholarly journals Innovations in anaerobic digestion: a model-based study

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Karol Postawa ◽  
Jerzy Szczygieł ◽  
Marek Kułażyński
Keyword(s):  
Mathematical Model ◽  
Anaerobic Digestion ◽  
Production Efficiency ◽  
Biogas Production ◽  
Biogas Plant ◽  
Methane Content ◽  
Pig Manure ◽  
Pig Slurry ◽  
Production Chain ◽  
The Impact

Abstract Background Increasing the efficiency of the biogas production process is possible by modifying the technological installations of the biogas plant. In this study, specific solutions based on a mathematical model that lead to favorable results were proposed. Three configurations were considered: classical anaerobic digestion (AD) and its two modifications, two-phase AD (TPAD) and autogenerative high-pressure digestion (AHPD). The model has been validated based on measurements from a biogas plant located in Poland. Afterward, the TPAD and AHPD concepts were numerically tested for the same volume and feeding conditions. Results The TPAD system increased the overall biogas production from 9.06 to 9.59%, depending on the feedstock composition, while the content of methane was slightly lower in the whole production chain. On the other hand, the AHPD provided the best purity of the produced fuel, in which a methane content value of 82.13% was reached. At the same time, the overpressure leads to a decrease of around 7.5% in the volumetric production efficiency. The study indicated that the dilution of maize silage with pig manure, instead of water, can have significant benefits in the selected configurations. The content of pig slurry strengthens the impact of the selected process modifications—in the first case, by increasing the production efficiency, and in the second, by improving the methane content in the biogas. Conclusions The proposed mathematical model of the AD process proved to be a valuable tool for the description and design of biogas plant. The analysis shows that the overall impact of the presented process modifications is mutually opposite. The feedstock composition has a moderate and unsteady impact on the production profile, in the tested modifications. The dilution with pig manure, instead of water, leads to a slightly better efficiency in the classical configuration. For the TPAD process, the trend is very similar, but the AHPD biogas plant indicates a reverse tendency. Overall, the recommendation from this article is to use the AHPD concept if the composition of the biogas is the most important. In the case in which the performance is the most important factor, it is favorable to use the TPAD configuration.

scholarly journals Irrigation Timing as a Practice of Effective Weed Management in Established Alfalfa (Medicago sativa L.) Crop

Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 550
Author(s):  
Panagiotis Kanatas ◽  
Ioannis Gazoulis ◽  
Ilias Travlos
Keyword(s):  
Medicago Sativa ◽  
Weed Management ◽  
Cultural Practices ◽  
Block Design ◽  
Chenopodium Album ◽  
Stand Density ◽  
Climatic Conditions ◽  
Amaranthus Retroflexus ◽  
Forage Yield ◽  
Medicago Sativa L

Irrigation is an agronomic practice of major importance in alfalfa (Medicago sativa L), especially in the semiarid environments of Southern Europe. Field experimentation was conducted in Western Greece (2016–2018) to evaluate the effects of irrigation timing on weed presence, alfalfa yield performance, and forage quality. In a randomized complete block design (four replications), two cultivars (“Ypati 84” and “Hyliki”) were the main plots, while three irrigation timings were the subplots (split-plot). The irrigation timings were IT-1, IT-2, and IT-3, denoting irrigation 1 week before harvest, 1 week after harvest, and 2 weeks after harvest, respectively. IT-1 reduced Solanum nigrum L. density by 54% and 79% as compared to IT-3 and IT-2, respectively. Chenopodium album L. density was the highest under IT-2. IT-3 resulted in 41% lower Amaranthus retroflexus L. density in comparison to IT-2, while the lowest values were observed under IT-1. Stand density and stems·plant−1 varied between years (p ≤ 0.05). Mass·stem−1 and alfalfa forage yield were affected by the irrigation timings (p ≤ 0.001). Total weed density and forage yield were negatively correlated in both the second (R2 = 87.013%) and the fourth (R2 = 82.691%) harvests. IT-1 and IT-3 increased forage yield, leaf per stem ratio, and crude protein as compared to IT-2. Further research is required to utilize the use of cultural practices for weed management in perennial forages under different soil and climatic conditions.

Floristic composition and relative abundance of weeds in annual crops of Manitoba

1991 ◽  
Vol 71 (3) ◽  
pp. 831-839 ◽  
Author(s):  
A. G. Thomas
Keyword(s):  
Relative Abundance ◽  
Chenopodium Album ◽  
Floristic Composition ◽  
Sampling Procedure ◽  
Amaranthus Retroflexus ◽  
Wild Buckwheat ◽  
Wild Oats ◽  
Wild Mustard ◽  
Green Foxtail ◽  
Lamb’S Quarters

Annual surveys for weeds of fields seeded to spring wheat, barley, oats, flax, and canola in Manitoba were conducted during 1978, 1979, and 1981. Fields were surveyed during July and early August each year using a stratified random sampling procedure. Data for the crops and years were combined for analysis. The frequency, the area infested, and the density of the infestation were determined for each species. These three measures of the abundance of the weed were combined into a single synthetic value called relative abundance. Nine of the 152 species recorded by the surveyors accounted for 77% of the total relative abundance. Ranked in order by relative abundance, these species were green foxtail (Setaria viridis (L.) Beauv.), wild oats (Avena fatua L.), wild buckwheat (Polygonum convolvulus L.), annual smartweed (Polygonum spp.), Canada thistle (Cirsium arvense (L.) Scop.), lamb's-quarters (Chenopodium album L.), wild mustard (Sinapis arvensis L.), perennial sow-thistle (Sonchus arvensis L.), and redroot pigweed (Amaranthus retroflexus L.). Green foxtail was the predominant weed with an abundance value three times larger than wild oats or wild buckwheat. The pattern of dominance found in Manitoba fields was similar to results from comparable surveys in Saskatchewan and North Dakota. Key words: Relative abundance, weed survey, weed density, green foxtail, wild oats, wild buckwheat

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