Systemic Crop Signaling for Automatic Recognition of Transplanted Lettuce and Tomato under Different Levels of Sunlight for Early Season Weed Control

Conventional cultivation works to control weeds between the rows, but it ignores the weeds in crop rows which are most competitive with crops. Many vegetable crops still require manual removal of intra-row weeds not otherwise controlled by herbicides or conventional cultivation. The increasing labor costs of weed control and the continued emergences of herbicide-resistant weeds are threatening grower ability to manage weeds and maintain profitability. Intra-row weeders are commercially available but work best in low weed populations. One strategy for rapid weed crop differentiation is to utilize a machine-detectable compound to mark a crop. This paper proposes a new systemic plant signaling technology that can create machine-readable crops to facilitate the automated removal of intra-row weeds in early growth stages. Rhodamine B (Rh–B) is an efficient systemic compound to label crop plants due to its membrane permeability and unique fluorescent properties. The project involves applying solutions of Rh–B at 60 ppm to the roots of lettuce and tomato plants prior to transplantation to evaluate Rh–B persistence in plants under different levels of sunlight. Lettuce and tomato seedlings with the systemic Rh–B should be reliably recognized during their early growth stages. An intelligent robot is expected to be developed to identify the locations of plants based on the systemic signal inside. Reduced light treatments should help to alleviate the photodegradation of Rh–B in plants. After being exposed to full sunlight for 27 days, the systemic Rh–B would be detectable in tomato branches and lettuce ribs, and these plants are tolerant to root treatments with this fluorescent compound. This paper describes the project background and plan as well as the anticipated contributions of the research to allow the machine vision system to reliably identify the crop plants, and thus showing technical feasibility for outdoor weed control.

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Tulip (Tulipaspp.), Daffodil (Narcissusspp.), and Iris (Irisspp.) Response to Preemergence Herbicides

Weed Technology ◽

10.1017/s0890037x00040690 ◽

1996 ◽

Vol 10 (4) ◽

pp. 710-715 ◽

Cited By ~ 5

Author(s):

Kassim A Al-Khatib

Keyword(s):

Weed Control ◽

Early Growth ◽

Growth Stages ◽

Flower Quality ◽

Preemergence Herbicides ◽

Bulb Yield

Broadleaf weed control and tulip, daffodil, and iris response to alachlor, dithiopyr, diuron, isoxaben, napropamide, oryzalin, oxadiazon, oxyfluorfen, pendimethalin, pronamide, and thiazopyr applied preemergence were evaluated. All herbicides controlled broadleaf weeds for five months after application, but control with oxyfluorfen, pendimethalin, alachlor, pronamide, and napropamide decreased six months after application. The greatest weed control was with oxadiazon, isoxaben, thiazopyr, dithiopyr, and diuron, whereas the least weed control was with napropamide and alachlor. In general, tulip was more sensitive to herbicides than daffodil and iris. All herbicides injured tulips at early growth stages but bulb yield of tulip was reduced only by oxadiazon, oxyfluorfen at 0.28 kg ai/ha, pronamide, and dithiopyr. Tulip flower quality was reduced only by oxadiazon, oxyfluorfen at 0.28 lb/ha, and pronamide. Daffodil and iris were tolerant to thiazopyr, isoxaben, pronamide, alachlor, oryzalin, napropamide, and diuron.

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Problem Weed Control in Glyphosate-Resistant Soybean with Glyphosate Tank Mixes and Soil-Applied Herbicides

Weed Technology ◽

10.1614/wt-09-012.1 ◽

2009 ◽

Vol 23 (4) ◽

pp. 507-512 ◽

Cited By ~ 24

Author(s):

Stevan Z. Knezevic ◽

Avishek Datta ◽

Jon Scott ◽

Robert N. Klein ◽

Jeff Golus

Keyword(s):

Weed Control ◽

Cropping Systems ◽

Field Studies ◽

Early Growth ◽

Growth Stages ◽

Herbicide Application ◽

Weed Species ◽

Common Lambsquarters ◽

Field Bindweed ◽

Crop Planting

Although glyphosate controls many plant species, certain broadleaf weeds in Nebraska's cropping systems exhibit various levels of tolerance to the labeled rates of this herbicide, including ivyleaf morningglory, Venice mallow, yellow sweetclover, common lambsquarters, velvetleaf, kochia, Russian thistle, and field bindweed. Therefore, two field studies were conducted in 2004 and 2005 at Concord and North Platte, NE, to evaluate performance of (1) seven preemergence (PRE) herbicides and (2) glyphosate tank mixes applied postemergence (POST) at three application times for control of eight weed species that are perceived as problem weeds in glyphosate-resistant soybean in Nebraska. The PRE herbicides, including sulfentrazone plus chlorimuron, pendimethalin plus imazethapyr, imazaquin, and pendimethalin plus imazethapyr plus imazaquin provided more than 85% control of most weed species tested in this study 28 d after treatment (DAT). However, sulfentrazone plus chlorimuron and pendimethalin plus imazethapyr plus imazaquin were the only PRE treatments that provided more than 80% control of most weed species 60 DAT. In the POST glyphosate tank-mix study, the level of weed control was significantly affected by the timing of herbicide application; control generally decreased as weed height increased. In general, glyphosate tank mixes applied at the first two application times (early or mid-POST) with half label rates of lactofen, imazamox, imazethapyr, fomesafen, imazaquin, or acifluorfen, provided more than 80% control of all species that were 20 to 30 cm tall except ivyleaf morningglory, Venice mallow, yellow sweetclover, and field bindweed. Glyphosate tank mixes applied late POST with lactofen, imazethapyr, or imazaquin provided more than 70% control of common lambsquarters, velvetleaf, kochia, and Russian thistle that were 30 to 50 cm tall. Overall, glyphosate tank mixes with half label rates of chlorimuron or acifluorfen were the best treatments; they provided more than 80% control of all the studied weed species when applied at early growth stages. Results of this study suggested that mixing glyphosate with other POST broadleaf herbicides, or utilizing soil-applied herbicides after crop planting helped effectively control most problematic weeds in glyphosate-resistant soybean in Nebraska.

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HIGH-SPEED CULTIVATION OF VEGETABLE CROPS WITH FINGER-WHEEL CULTIVATORS

HortScience ◽

10.21273/hortsci.31.5.748c ◽

1996 ◽

Vol 31 (5) ◽

pp. 748c-748

Author(s):

R.L. Parish ◽

R.P. Bracy ◽

W.C. Porter

Keyword(s):

Weed Control ◽

High Speed ◽

Crop Plants ◽

Crop Damage ◽

Vegetable Crops ◽

Agricultural Experiment Station ◽

Cultural System ◽

Experiment Station ◽

Wheel Rolling ◽

Agricultural Experiment

The Precision Cultural System (PCS) developed by the Louisiana Agricultural Experiment Station allows simple and precise cultivation of vegetable crops; however, speed of the cultivators in small vegetable crops has been limited. The standard PCS sweep cultivator was limited to about 1.6–2.4 km·h–1 in small crops because it would throw soil over the crop plants at higher speed. The standard PCS rotary tiller cultivator could operate at 3.2–4.8 km·h–1 in small crops but could not be operated faster in larger crops, due to its tendency to “walk” out of the soil at higher speeds. The standard PCS sweep cultivator was modified by replacing the sweeps between the twin drills with two pairs of straight finger-wheel (“rolling cultivator”) spiders non-angled and in tandem. The finger-wheel gangs on the bed sides were also inactivated by raising them above the soil. The resulting PCS cultivator was successfully operated in very small crop plants (≤25 mm high) at speeds of 8–10 km·h–1 with no crop damage. The cultivator could then be easily refitted for standard sweep cultivation on subsequent passes. No reductions in weed control or yield of mustard, kale, turnip, or spinach were noted when using the high-speed system.

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Early Postemergence Control of Woodland Bittercress (Cardamine flexuosa With.) and Yellow Woodsorrel (Oxalis stricta L.) with Dithiopyr and Isoxaben Combinations1

Journal of Environmental Horticulture ◽

10.24266/0738-2898-36.3.114 ◽

2018 ◽

Vol 36 (3) ◽

pp. 114-118

Author(s):

Debalina Saha ◽

S. Christopher Marble ◽

Annette Chandler

Keyword(s):

Weed Control ◽

Growth Stage ◽

Early Growth ◽

Growth Stages ◽

Fresh Weight ◽

Weed Species ◽

Leaf Stage ◽

Large Growth ◽

Cardamine Flexuosa ◽

Weight Data

Abstract The objective of this research was to evaluate dithiopyr and isoxaben combinations and indaziflam (Marengo) for early postemergence control of woodland bittercress (Cardamine flexuosa) and yellow woodsorrel at 4 different early growth stages. Herbicides evaluated included sprayable formulations of isoxaben, dithiopyr + isoxaben, dithiopyr, indaziflam, and prodiamine + isoxaben without any surfactants. Woodland bittercress growth stages included seed production (extra-large), recently flowered (large), 6 to 9 leaf (medium) or in 2 to 5 leaf stage (small), while yellow woodsorrel growth stages included 8 to 12 leaf stage (extra-large), 4 to 6 leaf stage (large), 2 to 4 leaf stage (medium) and cotyledon to 1 leaf stage (small). Shoot fresh weight data showed all treatments provided ≤98% of woodland bittercress at the small stage. Dithiopyr + isoxaben (98%), isoxaben (90%), and indaziflam (93%) provided the highest level of woodland bittercress control at the medium stage and were the only treatments providing acceptable control (≥80%). In the large stage, dithiopyr + isoxaben provided acceptable control (80%) and outperformed other treatments. All treatments with the exception of isoxaben generally provided acceptable control of yellow woodsorrel up to the large growth stage. Only indaziflam (86% control) provided acceptable control at the extra-large stage. Index words: herbicide, postemergence weed control, container-grown plants, phytotoxic damages. Herbicides used in this study: isoxaben (Gallery® 4SC) N-[3-(1-ethyl-1-methylpropyl)- 5-isoxazolyl]-2,6-dimethoxybenzamide; dithiopyr (Dimension® 2EW) S,S'-dimethyl 2-(difluoromethyl)-4- (2-methylpropyl)-6-(trifluoromethyl)- 3,5-pyridinedicarbothioate; indaziflam (Specticle® FLO) N-[(1R,2S)-2,3-dihydro-2,6-dimethyl-1H-inden-1-yl]-6-(1-fluoroethyl)-1,3,5-triazine-2,4-diamine; prodiamine + isoxaben (Gemini® SC) 2,4-dinitro-N3,N3-dipropyl-6-(trifluoromethyl)-1,3-benzenediamine + N-[3-(1-ethyl-1-methylpropyl)- 5-isoxazolyl]-2,6-dimethoxybenzamide; dithiopyr + isoxaben (Dimension® + Gallery®) S,S'-dimethyl 2-(difluoromethyl)-4- (2-methylpropyl)-6-(trifluoromethyl)- 3,5-pyridinedicarbothioate + N-[3-(1-ethyl-1-methylpropyl)- 5-isoxazolyl]-2,6-dimethoxybenzamide. Weed species evaluated: woodland bittercress (flexuous bittercress) (Cardamine flexuosa With.); yellow woodsorrel (Oxalis stricta L.).

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CONSTRUCTING A DEMONSTRATION VEGETABLE GARDEN

HortScience ◽

10.21273/hortsci.27.6.671f ◽

1992 ◽

Vol 27 (6) ◽

pp. 671f-671

Author(s):

M. Marutani ◽

R. Quitugua ◽

C. Simpson ◽

R. Crisostomo

Keyword(s):

Weed Control ◽

Cultural Practices ◽

Irrigation System ◽

Agricultural Science ◽

Drip Irrigation System ◽

Vegetable Crops ◽

University Campus ◽

Crop Cover ◽

Different Types ◽

The University

A demonstration vegetable garden was constructed for students in elementary, middle and high schools to expose them to agricultural science. On Charter Day, a University-wide celebration, students were invited to the garden on the University campus. The purpose of this project was twofold: (1) for participants to learn how to make a garden and (2) for visitors to see a variety of available crops and cultural techniques. Approximately 30 vegetable crops were grown. The garden also presented some cultural practices to improve plant development, which included weed control by solarization, mulching, a drip irrigation system, staking, shading and crop cover. Different types of compost bins were shown and various nitrogen-fixing legumes were displayed as useful hedge plants for the garden.

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RESPONSE OF GERMINATION AND SEEDLING GROWTH OF SOME VEGETABLE CROPS TO DIFFERENT LEVELS OF MAGNETIZED SALINE WATER IRRIGATION

Egyptian Journal of Applied Science ◽

10.21608/ejas.2019.105427 ◽

2019 ◽

Vol 34 (9) ◽

pp. 201-224

Keyword(s):

Seedling Growth ◽

Saline Water ◽

Vegetable Crops ◽

Saline Water Irrigation ◽

Different Levels

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Osmotic Stress or Ionic Composition: Which Affects the Early Growth of Crop Species More?

Agronomy ◽

10.3390/agronomy11030435 ◽

2021 ◽

Vol 11 (3) ◽

pp. 435

Author(s):

Agnieszka Ludwiczak ◽

Monika Osiak ◽

Stefany Cárdenas-Pérez ◽

Sandra Lubińska-Mielińska ◽

Agnieszka Piernik

Keyword(s):

Osmotic Stress ◽

Stress Responses ◽

Ionic Composition ◽

Degradation Process ◽

Early Growth ◽

Cultivated Plants ◽

C3 Plants ◽

Growth Stages ◽

Crop Species ◽

Ionic Salt

Salinization is a key soil degradation process. An estimated 20% of total cultivated lands and 33% of irrigated agricultural lands worldwide are affected by high salinity. Much research has investigated the influence of salt (mainly NaCl) on plants, but very little is known about how this is related to natural salinity and osmotic stress. Therefore, our study was conducted to determine the osmotic and ionic salt stress responses of selected C3 and C4 cultivated plants. We focused on the early growth stages as those critical for plant development. We applied natural brine to simulate natural salinity and to compare its effect to NaCl solution. We assessed traits related to germination ability, seedlings and plantlet morphology, growth indexes, and biomass and water accumulation. Our results demonstrate that the effects of salinity on growth are strongest among plantlets. Salinity most affected water absorption in C3 plants (28% of total traits variation), but plant length in C4 plants (17–27%). Compensatory effect of ions from brine were suggested by the higher model plants’ growth success of ca 5–7% under brine compared to the NaCl condition. However, trait differences indicated that osmotic stress was the main stress factor affecting the studied plants.

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Evaluation of weed control in acetyl coA carboxylase-resistant rice with mixtures of quizalofop and auxinic herbicides

Weed Technology ◽

10.1017/wet.2019.134 ◽

2019 ◽

Vol 34 (4) ◽

pp. 498-505

Author(s):

Tameka L. Sanders ◽

Jason A. Bond ◽

Benjamin H. Lawrence ◽

Bobby R. Golden ◽

Thomas W. Allen ◽

...

Keyword(s):

Weed Control ◽

Rice Yield ◽

Field Studies ◽

Growth Stages ◽

Acetyl Coa Carboxylase ◽

Acetyl Coa ◽

Herbicide Treatments ◽

Herbicide Mixture ◽

Sequential Treatments ◽

And Control

AbstractRice with enhanced tolerance to herbicides that inhibit acetyl coA carboxylase (ACCase) allows POST application of quizalofop, an ACCase-inhibiting herbicide. Two concurrent field studies were conducted in 2017 and 2018 near Stoneville, MS, to evaluate control of grass (Grass Study) and broadleaf (Broadleaf Study) weeds with sequential applications of quizalofop alone and in mixtures with auxinic herbicides applied in the first or second application. Sequential treatments of quizalofop were applied at 119 g ai ha−1 alone and in mixtures with labeled rates of auxinic herbicides to rice at the two- to three-leaf (EPOST) or four-leaf to one-tiller (LPOST) growth stages. In the Grass Study, no differences in rice injury or control of volunteer rice (‘CL151’ and ‘Rex’) were detected 14 and 28 d after last application (DA-LPOST). Barnyardgrass control at 14 and 28 DA-LPOST with quizalofop applied alone or with auxinic herbicides EPOST was ≥93% for all auxinic herbicide treatments except penoxsulam plus triclopyr. Barnyardgrass control was ≥96% with quizalofop applied alone and with auxinic herbicides LPOST. In the Broadleaf Study, quizalofop plus florpyrauxifen-benzyl controlled more Palmer amaranth 14 DA-LPOST than other mixtures with auxinic herbicides, and control with this treatment was greater EPOST compared with LPOST. Hemp sesbania control 14 DA-LPOST was ≤90% with quizalofop plus quinclorac LPOST, orthosulfamuron plus quinclorac LPOST, and triclopyr EPOST or LPOST. All mixtures except quinclorac and orthosulfamuron plus quinclorac LPOST controlled ivyleaf morningglory ≥91% 14 DA-LPOST. Florpyrauxifen-benzyl or triclopyr were required for volunteer soybean control >63% 14 DA-LPOST. To optimize barnyardgrass control and rice yield, penoxsulam plus triclopyr and orthosulfamuron plus quinclorac should not be mixed with quizalofop. Quizalofop mixtures with auxinic herbicides are safe and effective for controlling barnyardgrass, volunteer rice, and broadleaf weeds in ACCase-resistant rice, and the choice of herbicide mixture could be adjusted based on weed spectrum in the treated field.

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Coastal Mangrove Response to Marine Erosion: Evaluating the Impacts of Spatial Distribution and Vegetation Growth in Bangkok Bay from 1987 to 2017

Remote Sensing ◽

10.3390/rs12020220 ◽

2020 ◽

Vol 12 (2) ◽

pp. 220 ◽

Cited By ~ 2

Author(s):

Han Xiao ◽

Fenzhen Su ◽

Dongjie Fu ◽

Qi Wang ◽

Chong Huang

Keyword(s):

Spatial Distribution ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Mangrove Ecosystem ◽

Early Growth ◽

Growth Stages ◽

Human Disturbances ◽

Vegetation Growth ◽

Two Parameters ◽

The Impact

Long time-series monitoring of mangroves to marine erosion in the Bay of Bangkok, using Landsat data from 1987 to 2017, shows responses including landward retreat and seaward extension. Quantitative assessment of these responses with respect to spatial distribution and vegetation growth shows differing relationships depending on mangrove growth stage. Using transects perpendicular to the shoreline, we calculated the cross-shore mangrove extent (width) to represent spatial distribution, and the normalized difference vegetation index (NDVI) was used to represent vegetation growth. Correlations were then compared between mangrove seaside changes and the two parameters—mangrove width and NDVI—at yearly and 10-year scales. Both spatial distribution and vegetation growth display positive impacts on mangrove ecosystem stability: At early growth stages, mangrove stability is positively related to spatial distribution, whereas at mature growth the impact of vegetation growth is greater. Thus, we conclude that at early growth stages, planting width and area are more critical for stability, whereas for mature mangroves, management activities should focus on sustaining vegetation health and density. This study provides new rapid insights into monitoring and managing mangroves, based on analyses of parameters from historical satellite-derived information, which succinctly capture the net effect of complex environmental and human disturbances.

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