Chemical weed control in oil-seed poppy (Papaver somniferum)

1977 ◽  
Vol 17 (88) ◽  
pp. 837 ◽  
Author(s):  
BJ Baldwin
Keyword(s):  
Weed Control ◽  
Crop Production ◽  
Field Experiments ◽  
Crop Yields ◽  
Chenopodium Album ◽  
Papaver Somniferum ◽  
Significant Interaction Effect ◽  
North West ◽  
Oil Seed ◽  
Yield Responses

Field experiments were conducted in north-west Tasmania to assess the herbicides diquat and nitrofen, used singly and in combination, for selective post-emergence weed control in oil-seed poppies (Papaver somniferum). The species of weeds infesting the crop influenced yield responses to the herbicides. In the absence of fat hen (Chenopodium album) and fumitory (Fumaria muralis), crop production increased linearly with rate of diquat. The highest rate of diquat (280 g ha-1) produced a yield that was not significantly different (P = 0.05) from the hand-weeded control. In the presence of these two weeds, linear yield responses to rates of both diquat and nitrofen were obtained. There was no significant interaction effect on crop yields between these two herbicides, but a mixture of both chemicals was required for effective weed control. The tolerance of the crop to the herbicides was measured in the absence of weed competition. No effects on crop yields were obtained, although some treatments retarded the growth of the crop and caused a significant (P = 0.05) reduction in the height of the crop at flowering.

Weed population responses to weed control practices. I. Seed bank, weed populations, and crop yields

Weed Science ◽  
1999 ◽  
Vol 47 (4) ◽  
pp. 416-422 ◽  
Author(s):  
Douglas D. Buhler
Keyword(s):  
Weed Control ◽  
Field Experiments ◽  
Crop Yields ◽  
Initial Density ◽  
Control Treatment ◽  
Weed Seed ◽  
Weather Factors ◽  
Giant Foxtail ◽  
Broadleaf Species ◽  
Yield Responses

Weed control practices affected the weed seed content of the soil, weed seedling populations, and corn and soybean yields in two 4-yr field experiments. When the initial weed seed density was high, giant foxtail seed numbers in soil declined rapidly under weed-free conditions. Changes in seed densities when initial densities were low varied over years. Mechanical and chemical control treatments had variable effects on weed seed numbers over the course of the experiment. Weed seed numbers and weed densities were sometimes greater if herbicides were banded, but crop yields were similar to full-rate herbicides in both experiments in all years. When the initial density was low, giant foxtail seed numbers in soil increased over the course of the experiment regardless of the weed control treatment. Seed densities of broadleaf species decreased under the same conditions. Also, when initial weed densities were low, weed control and crop yields were less sensitive to weed control practices than at high weed densities. Weather factors that influenced treatment efficacy had a major affect on weed populations and crop yield responses to the weed control treatments over years. The interactions of weed control practices, weed populations, and crop yields were complex. Initial weed density and species composition interacted with weed control treatments and weather patterns to generate the results observed.

Herbicide Inputs for a New Agronomic Crop, Annual Wormwood (Artemisia annua)

1991 ◽  
Vol 5 (1) ◽  
pp. 117-124 ◽  
Author(s):  
Charles T. Bryson ◽  
Edward M. Croom
Keyword(s):  
Clinical Trials ◽  
Weed Control ◽  
Crop Production ◽  
Large Scale ◽  
Field Experiments ◽  
Production Systems ◽  
Artemisia Annua ◽  
Small Scale ◽  
Herbicide Treatments ◽  
Large Scale Cultivation

Annual wormwood has been cultivated on a small scale for production of the artemisinin class of antimalarial drugs in sufficient quantities for preclinical and clinical trials. Large scale cultivation will require a reliable, efficient crop production system. Production systems using 32 herbicides alone or in combinations were evaluated in growth chamber, greenhouse, and field experiments at Stoneville, MS from 1985 through 1988. The herbicide treatments that provided the best weed control were (A) metolachlor at 2.2 kg ai ha-1preemergence (PRE), (B) chloramben at 2.2 kg ai ha-1(PRE), or (C) trifluralin at 0.6 kg ai ha-1preplant soil incorporated (PPI) followed by fluazifop at 0.2 + 0.2 kg ai ha-1postemergence broadcast (POST) and acifluorfen at 0.6 kg ai ha-1(POST). These herbicide production systems provided excellent weed control (≥85%) and minimal crop injury (≤10%) with no effect on crop height or weight at harvest. Production of artemisinin was not reduced by herbicide treatments A, B, and C in 1987 and treatments B and C in 1988 when compared with the hand-weeded plots.

MIXED FARMING SYSTEMS IN TRANSITION: THE CASE OF FIVE VILLAGES ALONG A RAINFALL GRADIENT IN NORTH-WEST SYRIA

2003 ◽  
Vol 40 (1) ◽  
pp. 109-126 ◽  
Author(s):  
B. RISCHKOWSKY ◽  
E. F. THOMSON ◽  
R. SHNAYIEN ◽  
J. M. KING
Keyword(s):  
Crop Production ◽  
Crop Yields ◽  
National Policy ◽  
Farming Systems ◽  
Farm Income ◽  
Forage Crops ◽  
Rainfall Gradient ◽  
North West ◽  
Mixed Farming ◽  
The Many

The changes taking place in the mixed farming systems of northwest Syria were examined by re-visiting, in 1996 and 2000, five villages along a rainfall gradient. The villages had been surveyed first in 1977–79. In those villages with moderate rainfall, intensification of crop production, namely a trend towards cereal monoculture and the planting of tree crops, did not lead to specialization in cropping at the expense of sheep ownership. In contrast, households in the areas too dry for most rainfed crops except barley (Hordeum vulgare) were more likely to sell their sheep because they depended heavily on off-farm income. Increases in crop yields were found but these only benefited the families in villages in the higher rainfall zones. Conversely, with the exception of ewe fertility, there was little evidence of improvements in sheep productivity. The mixed farming systems in the five villages sampled are still passing through a period of transition, and the cropping component will undoubtedly continue to change. This is less likely to happen to the small ruminant component in the near future unless the sector is given higher priority in national policy. As a strategy to increase feed production and balance the crop rotations, the prospects for closer crop/livestock integration at the farm level are limited by the many difficulties associated with the introduction of leguminous pasture and forage crops.

The effects of time of weed removal on growth and yield of sugar beet

1979 ◽  
Vol 93 (3) ◽  
pp. 693-709 ◽  
Author(s):  
R. K. Scott ◽  
S. J. Wilcockson ◽  
F. R. Moisey
Keyword(s):  
Sugar Beet ◽  
Field Experiments ◽  
Yield Loss ◽  
Crop Yields ◽  
Chenopodium Album ◽  
Growth And Yield ◽  
Stellaria Media ◽  
Leaf Production ◽  
Irreversible Effects ◽  
Hand Weeding

SUMMARYField experiments at Sutton Bonington between 1970 and 1974 tested how crop yields were affected by hand weeding at different stages in the life of early- and latesown crops. Losses where weeds were never controlled ranged from 95% where tallgrowingChenopodium albumL. predominated to 50% whenStellaria media(L.) Vill. andTripleurospermum maritimumL.) Koch ssp.inodorumHyl ex. Vaarama (T.inodorum) were most involved.In five of the seven crops examined the latest date (X) at which weeding had to commence to prevent irreversible effects on growth and yield and the earliest date at which weeding could cease without yield loss (Y) coincided. For late March/early April sowings this occurred 6 weeks after crop emergence, while for late April/early May sowings in which events were more rapid the same stage was reached 4 weeks after emergence. For an early-sown crop in 1973, when rainfall was frequent and heavy andC. albumprolific, X preceded Y with an interval of 4 weeks between the two dates (4–8 weeks after crop emergence, mid-May to mid-June). In complete contrast for a late-sown crop in 1974, when the weather was exceptionally dry andC. albumvirtually absent, Y preceded X and a single weeding at any time between 2 and 8 weeks after emergence would have prevented yield loss.Sugar beet had generally reached the late singling stage (4–6 true leaves) by the time weeding must have commenced. During the next 6 weeks, final yield was depressed by 120–150kg/ha (1·;5%) with each day that weeds were allowed to remain. However, leaf production continued throughout the season and the crop was capable of recovering from early checks caused by weed competition. It proved possible for crops whose weights were depressed by 25–30% when first weeded to recover completely by harvest.

scholarly journals A global dataset for crop production under conventional tillage and no tillage systems

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Yang Su ◽  
Benoit Gabrielle ◽  
David Makowski
Keyword(s):  
Crop Production ◽  
Management Practices ◽  
Field Experiments ◽  
Crop Yields ◽  
Growing Season ◽  
Conventional Tillage ◽  
High Variability ◽  
Environmental Externalities ◽  
No Tillage ◽  
Insight Into

AbstractNo tillage (NT) is often presented as a means to grow crops with positive environmental externalities, such as enhanced carbon sequestration, improved soil quality, reduced soil erosion, and increased biodiversity. However, whether NT systems are as productive as those relying on conventional tillage (CT) is a controversial issue, fraught by a high variability over time and space. Here, we expand existing datasets to include the results of the most recent field experiments, and we produce a global dataset comparing the crop yields obtained under CT and NT systems. In addition to crop yield, our dataset also reports information on crop growing season, management practices, soil characteristics and key climate parameters throughout the experimental year. The final dataset contains 4403 paired yield observations between 1980 and 2017 for eight major staple crops in 50 countries. This dataset can help to gain insight into the main drivers explaining the variability of the productivity of NT and the consequence of its adoption on crop yields.

scholarly journals Effects of spacings and butachlor levels on weed control, growth and yield of NERICA 1 rice (Oryza sativa L. x Oryza glaberrima L.)

2017 ◽  
Vol 62 (4) ◽  
pp. 361-369
Author(s):  
Hassan Kasim ◽  
Ibrahim Musa ◽  
Mustapha Muhamman
Keyword(s):  
Oryza Sativa ◽  
Grain Yield ◽  
Weed Control ◽  
Crop Production ◽  
Field Experiments ◽  
Oryza Sativa L ◽  
Growth And Yield ◽  
Oryza Glaberrima ◽  
Control Growth ◽  
Main Plot

Poor agronomic practices coupled with herbicide mismanagement influence crop performance, yield, weed infestation and environmental hazards. Thus, field experiments were carried out to investigate the effect of spacing and reduced levels of butachlor on weed control and yield of NERICA 1 rice (Oryza sativa L. x Oryza glaberrima L). The experiments were conducted in the 2011 rainy season at the Teaching and Research Farm of the Department of Crop Production and Horticulture, Modibbo Adama University of Technology, Yola, and Lake Gerio, Yola in the 2012 dry season. Yola is located between latitude 9o14? N and longitude 12o28? E in the Northern Guinea Savanna ecological zone of Nigeria. Treatments consisted of four spacings (20 cm x 20 cm, etc.) and four butachlor levels (3, 2, 1, and 0 kg ha-1 a.i.). The experiments were laid out in a split-plot design with spacings assigned to the main plot and butachlor levels assigned to the sub-plot and were replicated three times. Data were taken on percentage establishment, number of leaves per plant, general weed cover, panicle length and grain yield per hectare. Data generated were subjected to analysis of variance. Means showing a significant F-test were separated using LSD. Results obtained showed that butachlor at 1 kg ha-1 and 14 cm x 14 cm spacing gave the highest grain yield of 1441 kg ha-1 and maximum weed control. They are, therefore, recommended for adoption by farmers in Yola and similar environments.

An attempt to improve the yield and quality of direct-drilled winter wheat grown continuously

1982 ◽  
Vol 99 (1) ◽  
pp. 163-172 ◽  
Author(s):  
J. R. Holbrook ◽  
J. D. Osborne ◽  
W. J. Ridgman
Keyword(s):  
Winter Wheat ◽  
Field Experiments ◽  
Crop Yields ◽  
Field Trials ◽  
Variety Trials ◽  
Time Of Application ◽  
Yield And Quality ◽  
New Varieties ◽  
Treatment Interaction ◽  
Yield Responses

SUMMARYSix field experiments on the effects of rate and time of application of nitrogen, three variety trials and one trial combining varieties with rates of application of nitrogen, all on winter wheat grown continuously and direct-drilled on a single farm, are described and the results discussed.The experiments showed that worthwhile yield responses could be obtained to very high rates of N application and that percentage protein in the grain increased linearly with amount of N supplied even to the highest rate (350 kg N/ha) applied. The effects of time of application were variable but there was a suggestion that applying the nitrogen in two doses in the spring gave more yield than a single dose, in one experiment. Applying some N in the autumn gave no more yield than applying it all in the spring.The variety trials gave results reasonably consistent with those of the National Institute of Agricultural Botany but the variety x nitrogen trial showed clear differences between varieties in response to nitrogen; the oldest variety, Maris Huntsman, showed a maximum at about 240 kg N/ha whereas none of the new varieties had reached their maximum by 270 kg N/ha.It is argued that field trials devoted to improving crop yields for a particular farm are worthwhile if site x treatment interaction is large and season x treatment interaction is small.

Application Timing of Lactofen for Broadleaf Weed Control in Peanut (Arachis hypogaea)

1993 ◽  
Vol 20 (2) ◽  
pp. 129-131 ◽  
Author(s):  
David L. Jordan ◽  
John W. Wilcut ◽  
Charles W. Swann
Keyword(s):  
Weed Control ◽  
Field Experiments ◽  
Chenopodium Album ◽  
Application Timing ◽  
Common Lambsquarters ◽  
Nitrobenzoic Acid ◽  
Eclipta Prostrata ◽  
Sida Spinosa ◽  
Prickly Sida ◽  
Herbicide Programs

Abstract Field experiments compared single and sequential applications of lactofen {+-2-ethoxy-1-methyl-2-oxoethyl 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoate} to the standard herbicide programs of alachlor [2-chloro-N-2,6-diethylphenyl)-N-(methoxymethyl)-acetamide] + paraquat (1,11-dimethyl-4,41-bipyridinium ion) and acifluorfen {5-[2-chloro-4-(trifluromethyl)phenoxy]-2-nitrobenzoic acid} + bentazon {3-(1-methyl-ethyl)-1H-2,1,3-benzothiadiazon-4(3H) 2,2-dioxide} for broadleaf weed control. A single late postemergence (LPOST) application of lactofen controlled morningglory species (Ipomoea spp.) and prickly sida (Sida spinosa L.) as well as lactofen applied early POST (EPOST) and LPOST. Lactofen applied sequentially at groundcracking (GC) and EPOST provided greater and/or more consistent control of common lambsquarters (Chenopodium album L.) and prickly sida than alachlor+paraquat applied GC or acifluorfen+bentazon applied LPOST. Ipomoea spp. control was less with a single LPOST application of lactofen than with acifluorfen+bentazon applied LPOST in 1988. Eclipta (Eclipta prostrata L.) was controlled with single or sequential lactofen applications and with acifluorfen+bentazon applied LPOST. Peanut yield was greater when lactofen was applied at GC followed by an EPOST application compared with a single application of lactofen applied LPOST, acifluorfen+ bentazon applied LPOST, or alachlor+paraquat applied GC.

scholarly journals Contributions of Climate and Soil Properties to Wheat and Maize Yield Based on Long-Term Fertilization Experiments

Plants ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2002
Author(s):  
Shengbao Wei ◽  
Anchun Peng ◽  
Xiaomin Huang ◽  
Aixing Deng ◽  
Changqing Chen ◽  
...  
Keyword(s):  
Soil Properties ◽  
Crop Yield ◽  
Crop Production ◽  
Field Experiments ◽  
Crop Yields ◽  
Climatic Factors ◽  
Maize Yield ◽  
Positive Interactions ◽  
Climate Factors ◽  
Average Contribution

Identifying the contributions of climate factors and soil fertility to crop yield is significant for the assessment of climate change impacts on crop production. Three 20-year field experiments were conducted in major Chinese wheat-maize cropping areas. Over the 20-year period, crop yield and soil properties showed significantly dissimilar variation trends under similar climate changes at each experimental site. The correlation between climatic factors and crop yield varied greatly among the fertilization regimes and experimental sites. Across all the fertilization regimes and the experimental sites, the average contribution rates of soil properties to wheat and maize yield were 45.7% and 53.2%, respectively, without considering climate factors, and 40.4% and 36.6%, respectively, when considering climate factors. The contributions of soil properties to wheat and maize yield variation when considering climate factors were significantly lower than those without considering climate factors. Across all experimental sites and all fertilization regimes, the mean contribution rates of climate factors to wheat and maize yield were 29.5% and 33.0%, respectively. The contribution rates of the interaction of climate and soil to wheat and maize yield were 3.7% and −0.9%, respectively. Under balanced fertilization treatments (NPK and NPKM), the change in the contribution rate of soil properties to wheat or maize yield was not obvious, and the average contribution rates of the interaction of climate and soil to wheat and maize yield were positive, at 14.8% and 9.5%, respectively. In contrast, under unbalanced fertilization treatments (CK and N), the contribution rates of soil properties to wheat or maize yield decreased, and the average contribution rates of the interaction of climate and soil were negative, at −7.4% and −11.2%, respectively. The above results indicate that climate and soil synergistically affected crop yields and that, with the optimization of the fertilization regime, positive interactions gradually emerged.

scholarly journals Effects of Living Mulch and Fertilizer on the Performance of Broccoli in Plasticulture

HortScience ◽  
2015 ◽  
Vol 50 (2) ◽  
pp. 218-224 ◽  
Author(s):  
Nicholas D. Warren ◽  
Richard G. Smith ◽  
Rebecca G. Sideman
Keyword(s):  
Cover Crops ◽  
Crop Production ◽  
Field Experiments ◽  
Crop Yields ◽  
Organic Fertilizer ◽  
Fertilizer Application ◽  
Italian Ryegrass ◽  
Living Mulch ◽  
Fertilizer Rate ◽  
Cash Crop

Living mulch systems allow cover crops to be grown during periods of cash crop production, thereby extending the duration of cover crop growth and associated beneficial agroecosystem services. However, living mulches may also result in agroecosystem disservices such as reduced cash crop yields if the living mulch competes with the crop for limiting resources. We examined whether the effects of an Italian ryegrass [Lolium multiflorum (Lam.) Husnot]–white clover (Trifolium repens L., cv. New Zealand) living mulch on broccoli (Brassica oleracea L. var. italica) yield and yield components were dependent on fertilizer rate in field experiments conducted in Durham, NH, in 2011 (Expt. 1) and 2012 (Expt. 2). Drip-irrigated broccoli was grown under a range of organic fertilizer application rates in beds covered with plastic, with and without a living mulch growing in the uncovered, interbed space. Broccoli yields were similar in the living mulch and bare soil controls under the highest rates of fertilizer application in Expt. 1. In Expt. 2, living mulch reduced broccoli yields from 28% to 63%, depending on fertilizer rate. Differences in leaf SPAD values suggest that yield reductions were attributable, in part, to competition for nitrogen; however, other factors likely played a role in determining living mulch effects. Despite yield reductions, the living mulch reduced the prevalence of hollow stem in broccoli in Expt. 1. Organic fertilizer may have inconsistent effects on broccoli yields in living mulch systems.

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