A Comparison of Four Orchard Floor Management Strategies for Lemons in Southwestern Arizona

Four orchard floor management strategies—disking, mowing, chemical mow, and clean culture using herbicides—were evaluated in a `Limoneira 8A Lisbon' lemon orchard in Southern Arizona, starting in the fall of 1993. Disking was the cultural practice used to manage the orchard floor before the start of the experiment. Although disking the orchard floor may have injured shallow tree roots, it provided satisfactory weed control except underneath the tree canopies where bermudagrass, purple nutsedge, and other weed species survived. Chemical mowing with Roundup at 1.168 L/ha did not provide satisfactory control of many weed species and required too many applications to be commercially feasible. This treatment was converted to a combination clean culture and disk treatment (clean and disk) in Summer 1995. Mowing the orchard suppressed broadleaf weed species, allowing the spread and establishment of grasses, primarily bermudagrass, and to a lesser extent, southern sandburr. A fall application of Solicam and Surflan followed by a summer spot treatment application of Roundup was used to control the weed flora in the clean culture treatment. Spot treatment applications of sethoxydim (Poast and Torpedo) were also made to control bermudagrass growing under the tree canopies in the clean culture treatment. Total 1995 yield of the mow, clean & disk, disk, and clean culture treatments were 4867, 5112, 5216, and 6042 kg of fruit, respectively. For the first harvest of 1995, the trees under clean culture also had significantly greater numbers of large fruit than did the trees under the other treatments.

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Weed Flora of Vineyards in Diyarbakır Province, Turkey

Agricultural Science Digest - A Research Journal ◽

10.18805/ag.d-259 ◽

2020 ◽

Author(s):

Cumali Özaslan ◽

Esmanur Pekcan Kaçar

Keyword(s):

Weed Management ◽

Cynodon Dactylon ◽

Management Strategies ◽

Hordeum Spontaneum ◽

Weed Species ◽

Coverage Area ◽

Avena Sterilis ◽

Important Place ◽

Alopecurus Myosuroides ◽

Weed Flora

Background: Viticulture occupies an important place in agricultural production of Diyarbakır province, Turkey. However, weeds significantly impair the productivity of vineyards in the province. The knowledge of weed flora of a particular region is crucial to develop region-specific weed management strategies. Methods: This study was carried out to determine the weed species, their densities and frequency of occurrence in 78 vineyards of 13 districts in Diyarbakır province. Exploratory surveys were conducted to record the occurrence, density and coverage area of weed species. A 1×1 m quadrate was used, which was randomly placed in vineyards and weed species falling within the quadrate were noted. Result: A total 165 weed species and 128 taxa belonging to 35 botanical families (1 parasitic, 16 monocotyledons and 18 dicotyledons) were identified from the surveyed area. The weed species’ density over the whole province was 91 weeds m-2. Avena sterilis L. was the most widespread weed with the highest density (9.93 plants m-2) in the surveyed area followed by Fumaria asepale Boiss. (7.18), Galium tricornutum (4.85), Ranunculus arvensis (3.82), Silene aegyptiaca (3.70), Bromus sterilis (3.64) Lamium purpureum (3.58), Hordeum spontaneum (3.35), Anthemis sp. (3.07), Crepis alpina (2.94), Thlaspi perfoliatum (2.91), Alopecurus myosuroides (2.81), Bongardia chrysogonum (2.80), Scandix pecten-veneris (2.24), Cynodon dactylon (1.71), Hypecoum procumbens (1.69), Lolium perenne (1.41), Sorghum halepense (1.33), Sinapis arvensis (1.24), Buglossoides arvense (1.22), Daucus carota (1.21), Trifolium nigrescens (1.21), Vicia hybrida (1.05), Senecio vernalis (1.04) and Ornithogalum narbonense (1.02). The most prevalent weed were L. purpureum (66.68%), Papaver sp. (66.49%), S. vernalis (65.82%), Anthemis sp. (65.10%), A. sterilis (63.07%), R. arvensis (60.44%), Convolvulus arvensis (56.76%), Carduus pycnocephalus (55.79%), G. tricornutum (55.43%), Fumaria asepale (55.05%), Crepis alpina (54.08%), Thlaspi perfoliatum (51.95%) and S. arvensis (51.04%).

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Influence of NPK fertilization on weed flora in maize field

Agrokémia és Talajtan ◽

10.1556/agrokem.63.2014.1.15 ◽

2014 ◽

Vol 63 (1) ◽

pp. 139-148 ◽

Cited By ~ 1

Author(s):

Éva Lehoczky ◽

M. Kamuti ◽

N. Mazsu ◽

J. Tamás ◽

D. Sáringer-Kenyeres ◽

...

Keyword(s):

Plant Nutrition ◽

Crop Production ◽

N Availability ◽

Weed Species ◽

Negative Effects ◽

Production Factors ◽

Maize Field ◽

Weed Flora ◽

Npk Fertilization

Plant nutrition is one of the most important intensification factors of crop production. The utilization of nutrients, however, may be modified by a number of production factors, including weed presence. Thus, the knowledge of occurring weed species, their abundance, nutrient and water uptake is extremely important to establish an appropriate basis for the evaluation of their risks or negative effects on crops. That is why investigations were carried out in a long-term fertilization experiment on the influence of different nutrient supplies (Ø, PK, NK, NPK) on weed flora in maize field.The weed surveys recorded similar diversity on the experimental area: the species of A. artemisiifolia, S. halepense and D. stramonium were dominant, but C. album and C. hybridum were also common. These species and H. annuus were the most abundant weeds.Based on the totalized and average data of all treatments, density followed the same tendency in the experimental years. It was the highest in the PK treated and untreated plots, and significantly exceeded the values of NK fertilized areas. Presumably the better N availability promoted the development of nitrophilic weeds, while the mortality of other small species increased.Winter wheat and maize forecrops had no visible influence on the diversity and the intensity of weediness. On the contrary, there were consistent differences in the density of certain weed species in accordance to the applied nutrients. A. artemisiifolia was present in the largest number in the untreated control and PK fertilized plots. The density of S. halepense and H. annuus was also significantly higher in the control areas. The number of their individuals was smaller in those plots where N containing fertilizers were used. Contrary to them, the density of D. stramonium, C. album and C. hybridum was the highest in the NPK treatments.

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Soil Nitrogen Movement under Sustainable Vegetable Production Systems

HortScience ◽

10.21273/hortsci.33.3.494f ◽

1998 ◽

Vol 33 (3) ◽

pp. 494f-495 ◽

Cited By ~ 1

Author(s):

Amy M. Johnson ◽

Greg D. Hoyt

Keyword(s):

Pest Management ◽

Soil Nitrogen ◽

Conservation Tillage ◽

Management Strategies ◽

Conventional Tillage ◽

Plant Diseases ◽

Vegetable Production ◽

Beneficial Arthropods ◽

Weed Species ◽

Available Nitrogen

An experiment was established to determine the effect of different tillage practices, vegetable crop rotations, and pest management strategies on crop yield, plant diseases, pest and beneficial arthropods, weed species changes over time, and soil environmental consequences. This poster describes nitrogen movement from the various treatments over a 3-year rotation. The treatments are: 1) conventional tillage with chemically based IPM; 2) conventional tillage with biologically based IPM; 3) conservation tillage with chemically based IPM; 4) conservation tillage with biologically based IPM; and 5) conventional tillage with no fertilizer or pest management. Mid-season soil analyses with depth showed chemical-fertilized plowed and conservation-tilled treatments with more soil available nitrogen at most depths compared to the biological-based IPM systems (soybean meal was used as a nitrogen source). However, the biological-based systems did supply enough soil nitrogen to produce similar yield results as the chemical-based systems. Less soil nitrate was measured in the 30- to 90-cm depths at harvest from the biological-based systems than chemical-based systems. Conservation-tilled systems had greater nitrate with depth compared to conventional-tilled systems.

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Factors affecting Cyperus difformis seed germination and seedling emergence

Planta Daninha ◽

10.1590/s0100-83582013000400008 ◽

2013 ◽

Vol 31 (4) ◽

pp. 823-832 ◽

Cited By ~ 7

Author(s):

A. Derakhshan ◽

J. Gherekhloo

Keyword(s):

Seed Germination ◽

Integrated Management ◽

Germination Rate ◽

Seedling Emergence ◽

Management Strategies ◽

Soil Surface ◽

Weed Species ◽

Factors Affecting ◽

Cyperus Difformis ◽

Emergence Patterns

Specific knowledge about the dormancy, germination, and emergence patterns of weed species aids the development of integrated management strategies. Laboratory studies were conducted to determine the effect of several environmental factors on seed germination and seedling emergence of Cyperus difformis. Germination of freshly harvested seeds was inhibited by darkness; however, when seeds were subsequently transferred to complete light they germinated readily. Our results showed that 2 wk of cold stratification overcome the light requirement for germination. Seeds of C. difformis were able to germinate over a broad range of temperatures (25/15, 30/20, 35/25, and 40/30 ºC day/night). The response of germination rate to temperature was described as a non-linear function. Based on model outputs, the base, the optimum and the ceiling temperatures were estimated as 14.81, 37.72 and 45 ºC, respectively. A temperature of 120 ºC for a 5 min was required to inhibit 50% of maximum germination. The osmotic potential and salinity required for 50% inhibition of maximum germination were -0.47 MPa and 135.57 mM, respectively. High percentage of seed germination (89%) was observed at pH=6 and decreased to 12% at alkaline medium (pH 9) pH. Seeds sown on the soil surface gave the greatest percentage of seedling emergence, and no seedlings emerged from seeds buried in soil at depths of 1 cm.

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Germination Biology of Sesbania (Sesbania cannabina): An Emerging Weed in the Australian Cotton Agro-environment

Weed Science ◽

10.1017/wsc.2018.62 ◽

2018 ◽

Vol 67 (1) ◽

pp. 68-76 ◽

Cited By ~ 2

Author(s):

Nadeem Iqbal ◽

Sudheesh Manalil ◽

Bhagirath S. Chauhan ◽

Steve W. Adkins

Keyword(s):

Seed Germination ◽

Management Strategies ◽

Moisture Stress ◽

Integrated Weed Management ◽

Burial Depth ◽

Weed Species ◽

Physical Dormancy ◽

Sesbania Cannabina ◽

Wide Range ◽

The Impact

AbstractSesbania [Sesbania cannabina(Retz.) Pers.] is a problematic emerging weed species in Australian cotton-farming systems. However, globally, no information is available regarding its seed germination biology, and better understanding will help in devising superior management strategies to prevent further infestations. Laboratory and glasshouse studies were conducted to evaluate the impact of various environmental factors such as light, temperature, salt, osmotic and pH stress, and burial depth on germination and emergence of two Australian biotypes ofS. cannabina. Freshly harvested seeds of both biotypes possessed physical dormancy. A boiling-water scarification treatment (100±2 C) of 5-min duration was the optimum treatment to overcome this dormancy. Once dormancy was broken, the Dalby biotype exhibited a greater germination (93%) compared with the St George biotype (87%). The nondormant seeds of both biotypes showed a neutral photoblastic response to light and dark conditions, with germination marginally improved (6%) under illumination. Maximum germination of both biotypes occurred under an alternating temperature regime of 30/20 and 35/25 C and under constant temperatures of 32 or 35 C, with no germination at 8 or 11 C. Seed germination of both biotypes decreased linearly from 87% to 14% with an increase in moisture stress from 0.0 to −0.8 MPa, with no germination possible at −1.0 MPa. There was a gradual decline in germination for both biotypes when imbibed in a range of salt solutions of 25 to 250 mM, with a 50% reduction in germination occurring at 150 mM. Both biotypes germinated well under a wide range of pH values (4.0 to 10.0), with maximum germination (94%) at pH 9.0. The greatest emergence rate of the Dalby (87%) and St George (78%) biotypes was recorded at a burial depth of 1.0 cm, with no emergence at 16.0 cm. Deep tillage seems to be the best management strategy to stopS. cannabina’s emergence and further infestation of cotton (Gossypium hirsutumL.) fields. The findings of this study will be helpful to cotton agronomists in devising effective, sustainable, and efficient integrated weed management strategies for the control ofS. cannabinain cotton cropping lands.

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Interactions of Nitrogen Source and Rate and Weed Removal Timing Relative to Nitrogen Content in Corn and Weeds and Corn Grain Yield

International Scholarly Research Notices ◽

10.1155/2017/8961367 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Alexandra M. Knight ◽

Wesley J. Everman ◽

David L. Jordan ◽

Ronnie W. Heiniger ◽

T. Jot Smyth

Keyword(s):

Grain Yield ◽

Weed Management ◽

Management Strategies ◽

Field Studies ◽

Weed Species ◽

Weed Interference ◽

Coated Urea ◽

N Fertility ◽

Corn Grain ◽

Corn Grain Yield

Adequate fertility combined with effective weed management is important in maximizing corn (Zea mays L.) grain yield. Corn uptake of nitrogen (N) is dependent upon many factors including weed species and density and the rate and formulation of applied N fertilizer. Understanding interactions among corn, applied N, and weeds is important in developing management strategies. Field studies were conducted in North Carolina to compare corn and weed responses to urea ammonium nitrate (UAN), sulfur-coated urea (SCU), and composted poultry litter (CPL) when a mixture of Palmer amaranth (Amaranthus palmeri S. Wats.) and large crabgrass (Digitaria sanguinalis L.) was removed with herbicides at heights of 8 or 16 cm. These respective removal timings corresponded with 22 and 28 days after corn planting or V2 and V3 stages of growth, respectively. Differences in N content in above-ground biomass of corn were noted early in the season due to weed interference but did not translate into differences in corn grain yield. Interactions of N source and N rate were noted for corn grain yield but these factors did not interact with timing of weed control. These results underscore that timely implementation of control tactics regardless of N fertility management is important to protect corn grain yield.

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Seed germination ecology of Conyza stricta Willd. and implications for management

PLoS ONE ◽

10.1371/journal.pone.0244059 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0244059

Author(s):

Safdar Ali ◽

Fakhar Din Khan ◽

Rehmat Ullah ◽

Rahmat Ullah Shah ◽

Saud Alamri ◽

...

Keyword(s):

Seed Germination ◽

Osmotic Potential ◽

Cropping Systems ◽

Seedling Emergence ◽

Management Strategies ◽

Conservation Agriculture ◽

Weed Species ◽

Seed Burial ◽

Germination Ecology ◽

Tillage Practices

Numerous cropping systems of the world are experiencing the emergence of new weed species in response to conservation agriculture. Conyza stricta Willd. is being a newly emerging weed of barley-based cropping systems in response to conservational tillage practices. Seed germination ecology of four populations (irrigated, rainfed, abandoned and ruderal habitats) was studied in laboratory and greenhouse experiments. The presence/absence of seed dormancy was inferred first, which indicated seeds were non-dormant. Seed germination was then recorded under various photoperiods, constant and alternating day/night temperatures, and pH, salinity and osmotic potential levels. Seedling emergence was observed from various seed burial depths. Seeds of all populations proved photoblastic and required 12-hour light/dark period for germination. Seeds of all populations germinated under 5–30°C constant temperature; however, peak germination was recorded under 17.22–18.11°C. Nonetheless, the highest germination was noted under 20/15°C alternating day/night temperature. Ruderal and irrigated populations better tolerated salinity and germinated under 0–500 mM salinity. Similarly, rainfed population proved more tolerant to osmotic potential than other populations. Seeds of all populations required neutral pH for the highest germination, whereas decline was noted in germination under basic and alkaline pH. Seedling emergence was retarded for seeds buried >2 cm depth and no emergence was recorded from >4 cm depth. These results add valuable information towards our understanding of seed germination ecology of C. stricta. Seed germination ability of different populations under diverse environmental conditions suspects that the species can present severe challenges in future if not managed. Deep seed burial along with effective management of the emerging seedlings seems a pragmatic option to manage the species in cultivated fields. However, immediate management strategies are needed for rest of the habitats.

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Solar Heating of the Soil: Involvement of Environmental Factors in the Weed Control Process

Weed Science ◽

10.1017/s0043174500058653 ◽

1984 ◽

Vol 32 (1) ◽

pp. 138-142 ◽

Cited By ~ 47

Author(s):

Baruch Rubin ◽

Abraham Benjamin

Keyword(s):

Cynodon Dactylon ◽

Soil Depth ◽

Control Process ◽

Solar Heating ◽

Cyperus Rotundus ◽

Weed Species ◽

Purple Nutsedge ◽

Deep Layers ◽

Hot Season ◽

Vegetative Propagules

Solar heating (SH) of wet soil by mulching it with transparent polyethylene (PE) during the hot season increased soil temperature in a typical daily course which varied with soil depth. Annual weed species responded to soil heating in the laboratory with the same pattern as under SH conditions in the field. Rhizomes of bermudagrass (Cynodon dactylonL. Pers. ♯3CYNDA) and johnsongrass (Sorghum halepenseL. Pers. ♯ SORHA) were very sensitive to heat treatment, but purple nutsedge (Cyperus rotundusL. ♯ CYPRO) tubers were able to survive temperatures as high as 80 C for 30 min. Species having big and heavy seeds or vegetative propagules were able to emerge from deep layers of soil, thus practically escaping the lethal temperature prevailing in the upper layer. Transparent and black PE mulching effectively prevented water loss from soil, as compared with perforated PE and nonmulched control. CO2concentration in the soil atmosphere under transparent PE mulching increased rapidly during the first week and reached a maximal level which was 20-fold higher than that formed in nonmulched soil. Ethylene at 0.2 ppm was detected only in a mulched soil environment. No differences in levels of CH4or CO were detected.

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Yellow and purple nutsedges survey in the southeastern Buenos Aires Province, Argentina

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2001000100025 ◽

2001 ◽

Vol 36 (1) ◽

pp. 205-209 ◽

Cited By ~ 2

Author(s):

Juan José Eyherabide ◽

María Inés Leaden ◽

Sara Alonso

Keyword(s):

Buenos Aires ◽

Management Strategies ◽

Buenos Aires Province ◽

Relative Importance ◽

Purple Nutsedge ◽

Yellow Nutsedge ◽

Perennial Weeds ◽

Heavy Infestation

A survey of 79 fields was conducted between December 1993 and January 1994, to determine the distribution and relative importance of species of the genus Cyperus, to justify developing management strategies in the southeastern of Buenos Aires Province, Argentina. Yellow and purple nutsedge were found in 43% and 9% respectively of the surveyed fields. Thirty eight per cent of the surveyed area showed a heavy infestation of yellow nutsedge, and in 90% of cases yellow nutsedge was invading fields cultivated with summer crops and associated with one or more of other seven perennial weeds, mainly bermudagrass.

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Model of rice (Oryza sativa) yield reduction as a function of weed interference

Weed Science ◽

10.1017/s0043174500092742 ◽

1997 ◽

Vol 45 (2) ◽

pp. 218-224 ◽

Cited By ~ 21

Author(s):

Karl W. VanDevender ◽

Thomas A. Costello ◽

Roy J. Smith

Keyword(s):

Weed Management ◽

Management Strategies ◽

Economic Assessment ◽

Richards Equation ◽

Yield Reduction ◽

Published Data ◽

Weed Species ◽

Individual Parameter ◽

Alternative Weed Control ◽

Parameter Values

Economic assessment of weed management strategies in rice is dependent upon a quantitative estimate of the yield impact of a given weed population. To assist rice producers in making such assessments, a mathematical model was developed to predict rice yield reduction as a function of weed density and duration of interference. The nonlinear empirical model was a unique 3-dimensional adaptation of the Richards equation with 4 parameters. Using published data, individual parameter values were fitted for each of 6 weed species interfering with either conventional or semi-dwarf statured rice cultivars. The functional form of the equation produced surfaces that were qualitatively consistent with available data and experience regarding rice-weed biology. Hence, predictions from the model should be useful and reliable in assessing the economic impact of weeds and in determining the feasibility of alternative weed control treatments for various field scenarios.

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