scholarly journals DIVERZITET I ANALIZA KVALITATIVNOG SASTAVA BILJNE ZAJEDNICE STRNIŠTA KAO POTENCIJALNE KRME

2021 ◽  
Author(s):  
Dusko Brkovic ◽  
◽  
Dalibor Tomic ◽  
Snežana Brankovic ◽  
◽  
...  

In the plant communities on stubble, 25 taxons were determined, classified into 22 genera and 13 families. Of the 7 most pre-stated families, five are present in this micro-company where asteraceae have 6 taxons (27.27%), Lamiaceae five species (20%) and Poaceae three representatives (12%). As feed can be used: Galinsoga parviflora Cav., Echinochloa crus-galli (L.) Beauv., Elymus repens (L.) Gould., Amaranthus retroflexus L., Chenopodium album L. and Leontodon hispidus L. Potentially toxic to domestic animals are: Colchicum autumnale L., Equisetum arvense L., Equisetum telmateia Ehrh., Ranunculus bulbosus L., Sonhus arvensis L.

Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 550
Author(s):  
Panagiotis Kanatas ◽  
Ioannis Gazoulis ◽  
Ilias Travlos

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.


1991 ◽  
Vol 71 (3) ◽  
pp. 831-839 ◽  
Author(s):  
A. G. Thomas

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


2012 ◽  
Vol 4 (3) ◽  
pp. 70-75 ◽  
Author(s):  
Hossein GHAMARI ◽  
Goudarz AHMADVAND

Dry bean is one of the most important pulse crops in Iran. Field study was conducted in 2011 to evaluate effects of weed competition from a natural flora on growth and yield of dry bean (Phaseolus vulgaris L.). The treatments consisted of weed infestation and weed removal periods (10, 20, 30, 40 and 50 days) after crop emergence. Control plots kept weed-infested and weed-free throughout growing season. To assess the weed competition effect on crop characteristics, Richards, Gompertz and logistic equations were fitted to the data. The most abundant weed species were Chenopodium album and Amaranthus retroflexus. Increase in duration of weed interference decreased the stem height of dry bean. At the end of the growing season, dry bean was 20 cm taller in season-long weed-free treatment compared to the season-long weed-infested treatment. As the number of days of weed interference increased, a declining trend of LAI and number of pods was observed. The minimum number of pods was obtained in season-long weed-infested treatment (5.01 pods/plant). Weed interference during the whole growing season, caused a 60% reduction in yield. Considering 5% and 10% acceptable yield lost, the critical period of weed competition was determined from 20 to 68 and 23 to 55 days after planting (DAE), respectively.


Land ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 967
Author(s):  
Aikaterini Voudouri ◽  
Evgenia Chaideftou ◽  
Athanassios Sfougaris

The topsoil seed bank was studied in four types of agricultural bird habitats: fields with cereals, maize, clover and tilled fields of a Mediterranean plain to determine the potentially richest habitat based on food supply for the wintering farmland birds. The diversity and abundance of topsoil seeds differed between seasons but did not differ significantly between habitats. The cereal habitat was the richest in food supply for the overwintering of farmland birds. The topsoil seed bank was dominated by Chenopodium album, Polygonum aviculare and Amaranthus retroflexus. The findings of this study provide insight for low-intensity management of higher-elevation mount agricultural areas of southern Mediterranean by preserving seed-rich habitats for farmland avifauna.


1957 ◽  
Vol 37 (1) ◽  
pp. 69-83 ◽  
Author(s):  
H. A. Friesen ◽  
D. R. Walker

Oats, flax and barley were sprayed with various formulations of MCP (2-methyl-4-chlorophenoxyacetic acid) and 2,4-D (2,4-dichlorophenoxyacetic acid) at a number of Experimental Farms in Western Canada in 1954 and 1955. Each formulation was applied at 4 and 8 ounces of acid equivalent per acre at each of two dates, viz., Date 1, when the weeds were in the seedling stage less than 3 inches in height; and Date 2, at a stage coinciding with the first appearance of buds on the major weed species.Stinkweed (Thlaspi arvense, L.), wild mustard (Brassica kaber (DC.) L.C. Wheeler var. pinnatifida (Stokes) L.C. Wheeler), lamb's quarters (Chenopodium album L.), Russian pigweed (Axyris amarantoides L.), and ball mustard (Neslia paniculata L.), were effectively controlled by each of the MCP and 2,4-D formulations used. Russian thistle (Salsola kali L.), and red-root pigweed (Amaranthus retroflexus L.), were not satisfactorily controlled by MCP, whereas hemp nettle (Galeopsis tetrahit L.) was not controlled by 2,4-D. Wild buckwheat (Polygonum convolvulus L.) was not controlled by any of the treatments. Each treatment was more effective when applied during the seedling stage of the weeds.On the basis of wood control and yield of grain the results of this study favour the use of MCP over 2,4-D with either oats or flax. Oats was significantly more tolerant to MCP, particularly if treated during the early growth stages when weed competition was most critical. With flax, the difference in tolerance was most pronounced in favour of MCP at the later date of treatment. The 2,4-D ester and low volatile ester resulted in a preponderance of plant deformities, lowered the yields of both oats and flax and delayed the maturity of flax significantly. Barley yields in this study were not adversely affected by any of the treatments.


Weed Science ◽  
1979 ◽  
Vol 27 (6) ◽  
pp. 608-611 ◽  
Author(s):  
A. G. Ogg ◽  
S. Drake

Alachlor [2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide] at 3.4 kg/ha, EPTC (S-ethyl dipropylthiocarbamate) + R-25788 (N,N-diallyl-2,2-dichloroacetamide) at 4.5 + 0.4 and 9.0 + 0.8 kg/ha, vernolate (S-propyl dipropylthiocarbamate) + R-25788 at 4.5 + 0.4 and 9.0 + 0.8 kg/ha, metolachlor [2-chloro N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] at 1.7 and 3.4 kg/ha, and metolachlor + procyazine {2-[[4-chloro-6-(cyclopropylamino)1,3,5-triazine-2-yl] amino]-2-methylpropanenitrile} at 1.3 + 1.3 kg/ha were preplant incorporated. These herbicides controlled 95% or more of the barnyardgrass [Echinochloa crus-galli (L.) Beauv.], common lambsquarters (Chenopodium album L.), redroot pigweed (Amaranthus retroflexus L.), Powell amaranth (A. powellii S. Wats.), and yellow foxtail [Setaria lutescens (Weigel) Hubb.] without injuring sweetcorn (Zea mays L. ‘Golden Jubilee’) or reducing corn yields or quality. Similar results were obtained with preplant incorporated applications of butylate (S-ethyldiisobutylthiocarbamate) + R-25788 at 4.5 + 0.2 kg/ha followed by a postemergence application of the amine salt of 2,4-D [(2,4-dichlorophenoxy)acetic acid] at 0.6 kg/ha. Metribuzin [4-amino-6-tert-butyl-3-(methylthio)-as-triazin-5(4H)-one] at 0.3 and 0.6 kg/ha and metribuzin + alachlor at 0.6 + 2.2 kg/ha applied preplant and incorporated reduced corn stands, primary ear production, and corn yields significantly. None of the herbicides significantly affected total sugars, reducing sugars, soluble solids, moisture content, or succulence of the corn.


Weed Science ◽  
1981 ◽  
Vol 29 (3) ◽  
pp. 349-355 ◽  
Author(s):  
Richard Behrens ◽  
M. A. Elakkad

To study rainfall effects, simulated rainfall was applied to velvetleaf (Abutilon theophrastiMedic.), common lambsquarters (Chenopodium albumL.), wild mustard [Brassica kaber(DC.) L. C. Wheeler var.pinnatifida(Stokes) L. C. Wheeler], soybean [Glycine max(L.) Merr. ‘Hodgson’], and redroot pigweed (Amaranthus retroflexusL.) in greenhouse and field studies following foliar applications of the alkanolamine (AKA) salt or the butoxyethanol (BE) ester of 2,4-D [(2,4-dichlorophenoxy)acetic acid] at rates that induced equivalent levels of phytotoxicity. Simulated rainfall less than 1 min after herbicide treatment reduced the phytotoxicity of the AKA salt of 2,4-D to a much greater extent than that of the BE ester with effects ranging from elimination of all injury from the AKA salt to soybeans to no reduction in phytotoxicity of the BE ester to common lambsquarters. The quantity of simulated rainfall required to induce maximum reductions in phytotoxicity of the BE ester ranged from 1 mm on common lambsquarters to 15 mm on velvetleaf. The time interval from 2,4-D treatment until rainfall required to achieve a phytotoxic response level of 80% of that attained without rainfall varied greatly among plant species and herbicide formulations; ranging from less than 1 min for the BE ester on common lambsquarters to more than 24 h for the AKA salt on velvetleaf. The addition of an alkylarylpolyoxyethylene glycol surfactant to 2,4-D spray solutions reduced herbicide rates required to induce equivalent levels of phytotoxicity, increased losses in phytotoxicity of the BE ester caused by rainfall, and reduced the time interval from treatment to rainfall required to attain an equivalent level of phytotoxicity with the AKA salt.


Weed Science ◽  
1979 ◽  
Vol 27 (1) ◽  
pp. 7-10 ◽  
Author(s):  
R. B. Taylorson

AbstractGermination of seeds of 10 grass and 33 broadleaved weed species was examined for response to ethylene. Germination was promoted in nine species, inhibited in two, and not affected in the remainder. Of the species promoted, common purslane (Portulaca oleraceaL.), common lambsquarters (Chenopodium albumL.), and several Amaranths, including redroot pigweed (Amaranthus retroflexusL.), were affected most. Transformation of phytochrome to the active form (Pfr) gave interactions that ranged from none to syntergistic with the applied ethylene. In subsequent tests seeds of purslane, redroot pigweed, and giant foxtail (Setaria faberiHerrm.), a species not responsive to ethylene, were examined for germination response to 14 low molecular weight hydrocarbon gases other than ethylene. Some stimulation by the olefins propylene and propadiene was found for purslane and pigweed. Propionaldehyde and butyraldehyde were slightly stimulatory to purslane only.


Weed Science ◽  
1979 ◽  
Vol 27 (4) ◽  
pp. 401-415 ◽  
Author(s):  
Robert N. Andersen ◽  
Willard L. Koukkari

In growth chamber studies, we measured the movement of cotyledons and leaves or leaflets in seedlings of nine weed species to determine: the magnitude of movement, whether movements followed a rhythmic pattern, and if rhythmic movements were endogenously controlled. Seedlings were always entrained under a 15-h light:9-h dark regime. Measurements were made at 3-h intervals for 3 to 4 days under four light regimes: alternating 15-h light:9-h dark; continuous light; one 15-h light:9-h dark span, followed by continuous light; and a 15-h light:9-h dark regime, in which the dark span was advanced 9 h (phase shift) when measurements were begun. No clearly defined pattern of leaf movement was found in wild mustard [Brassica kaber(DC.) L. C. Wheeler var.pinnatifida(Stokes) L. C. Wheeler]. Daily rhythmic leaf movements that did not appear to be endogenously controlled were found in redroot pigweed (Amaranthus retroflexusL.) and black nightshade (Solanum nigrumL.). Circadian rhythmic leaf movements that appeared to be under endogenous control were found in jimson-weed (Datura stramoniumL.), common lambsquarters (Chenopodium albumL.), common cocklebur (Xanthium pensylvanicumWallr.), prickly sida (Sida spinosaL.), sicklepod (Cassia obtusifoliaL.), and coffee senna (Cassia occidentalisL.).


1977 ◽  
Vol 57 (1) ◽  
pp. 243-249 ◽  
Author(s):  
RUSSELL TKACHUK ◽  
V. JEAN MELLISH

Weed seeds commonly found in Western Canadian cereals and oil seeds as dockage were examined for their amino acid, protein, oil and fiber contents. The weeds analyzed were Sinapis arvenis L.(wild mustard), Thlaspi arvense L. (stinkweed), Descurainia sophia (L.) Webb (flixweed), Polygonum convolvulus L. (wild buckwheat), Rumex pseudonatronatus L. (field dock), Avena fatua L. (wild oats), Setaria viridis (L.) Beauv. (green foxtail), Iva xanthifolia Nutt. (false ragweed), Chenopodium album L. (lamb’s-quarters), and Amaranthus retroflexus L. (redroot pigweed). Composite analysis showed that some of the weed seeds are high in protein and oil content. Amino acid analysis showed that many weeds have an excellent essential amino acid balance, and also a higher content of essential amino acids than do the commonly grown cereals. These results suggest that some weed seeds could be excellent sources of protein and oil for feed or food purposes.


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