Critical weed-free period for large crabgrass (Digitaria sanguinalis) in transplanted watermelon (Citrullus lanatus)

Removal and plant-back studies were conducted in North Carolina in 1991 and 1992 to determine the critical period of large crabgrass competition in transplanted triploid (seedless) watermelon. For every week that large crabgrass remained in watermelon, medium (3.6 to 7.3 kg) melon yield decreased 3,996 kg and 716 fruit ha−1. For every week that large crabgrass emergence was delayed, yield increased by 814 kg and 142 fruit ha−1. Likewise, for every week that large crabgrass remained in watermelon, marketable (3.6 kg and over) yield decreased 5,582 kg and 911 fruit ha−1. For every week that large crabgrass emergence was delayed, yield was increased 881 kg and 151 fruit ha−1. Large crabgrass emerging after 6 wk had no effect on marketable fruit or number of watermelon. To achieve the greatest quality or quantity of medium or marketable fruit, a large crabgrass-free period between 0 and 6 wk after transplanting was necessary.

Download Full-text

Interaction of 2,4-DB With Postemergence Graminicides

Peanut Science ◽

10.3146/i0095-3679-20-1-15 ◽

1993 ◽

Vol 20 (1) ◽

pp. 57-61 ◽

Cited By ~ 6

Author(s):

Alan C. York ◽

John W. Wilcut ◽

W. James Grichar

Keyword(s):

North Carolina ◽

Field Experiments ◽

Sorghum Halepense ◽

Grass Species ◽

Digitaria Sanguinalis ◽

Eleusine Indica ◽

Brachiaria Platyphylla ◽

Growing Conditions ◽

Large Crabgrass

Abstract Field experiments were conducted in North Carolina, Georgia, and Texas to determine if grass control is affected when postemergence-applied graminicides are mixed with 2,4-DB. Grass species evaluated included broadleaf signalgrass [Brachiaria platyphylla (Griseb.) Nash], goosegrass [Eleusine indica (L.) Gaertn.], johnsongrass [Sorghum halepense (L.) Pers.], large crabgrass [Digitaria sanguinalis (L.) Scop.], southern crabgrass [Digitaria ciliaris (Retz.) Koel.], and Texas panicum (Panicum texanum Buckl.). Mixing 2,4-DB with the graminicides reduced grass control 8 to 15% at five of 11 locations. The antagonism was not specific for a particular grass species or graminicide, and it was not restricted to grasses under adverse growing conditions. Applying the 2,4-DB 24 hours after graminicide application alleviated the antagonism. Applying the 2,4-DB 24 hours before the graminicides overcame the antagonism at three of the five locations.

Download Full-text

Critical Period for Weed Control in Grafted and Nongrafted Watermelon Grown in Plasticulture

Weed Science ◽

10.1017/wsc.2018.76 ◽

2018 ◽

Vol 67 (2) ◽

pp. 221-228 ◽

Cited By ~ 1

Author(s):

Matthew B. Bertucci ◽

Katherine M. Jennings ◽

David W. Monks ◽

Jonathan R. Schultheis ◽

Frank J. Louws ◽

...

Keyword(s):

Weed Control ◽

Critical Period ◽

Field Experiments ◽

Citrullus Lanatus ◽

Weed Species ◽

Yellow Nutsedge ◽

Study Results ◽

Seedless Watermelon ◽

Common Purslane ◽

Weed Removal

AbstractField experiments determined the critical period for weed control (CPWC) in grafted and nongrafted watermelon [Citrullus lanatus(Thumb.) Matsum. & Nakai] grown in plasticulture. Transplant types included ‘Exclamation’ seedless watermelon as the nongrafted control as well as Exclamation grafted onto two interspecific hybrid squash (ISH) rootstocks, ‘Carnivor’ and ‘Kazako’. To simulate weed emergence throughout the season, establishment treatments (EST) consisted of two seedlings each of common purslane (Portulaca oleraceaL.), large crabgrass [Digitaria sanguinalis(L.) Scop.], and yellow nutsedge (Cyperus esculentusL.) transplanted in a 15 by 15 cm square centered on watermelon plants at 0, 2, 3, 4, and 6 wk after watermelon transplanting (WATr) and remained until the final watermelon harvest at 11 WATr. To simulate weed control at different times in the season, removal treatments (REM) consisted of two seedlings of the same weed species transplanted in a 15 by 15 cm square centered on watermelon plants on the same day of watermelon transplanting and allowed to remain until 2, 3, 4, 6, and 11 WATr, at which time they were removed. Season-long weedy and weed-free controls were included for both EST and REM studies in both years. For all transplant types, aboveground biomass of weeds decreased as weed establishment was delayed and increased as weed removal was delayed. The predicted CPWC for nongrafted Exclamation and Carnivor required only a single weed removal between 2.3 and 2.5 WATr and 1.9 and 2.6 WATr, respectively, while predicted CPWC for Kazako rootstock occurred from 0.3 to 2.6 WATr. Our study results suggest that weed control for this mixed population of weeds would be similar between nongrafted Exclamation and Exclamation grafted onto Carnivor. But the observed CPWC of Exclamation grafted onto Kazako suggests that CPWC may vary with specific rootstock–scion combinations.

Download Full-text

Evaluating Cucurbit Rootstocks to Prevent Disease Caused by Pythium aphanidermatum and P. myriotylum on Watermelon

Plant Disease ◽

10.1094/pdis-03-20-0474-re ◽

2020 ◽

Vol 104 (11) ◽

pp. 3019-3025

Author(s):

Sean M. Toporek ◽

Anthony P. Keinath

Keyword(s):

Interspecific Hybrid ◽

Citrullus Lanatus ◽

Disease Incidence ◽

Bottle Gourd ◽

Stem Rot ◽

Lagenaria Siceraria ◽

Cucurbita Maxima ◽

Pythium Species ◽

Seedless Watermelon ◽

Marketable Fruit

Pythium species cause root and stem rot in watermelon (Citrullus lanatus), but cucurbit rootstocks used to graft watermelon have not been evaluated for resistance. P. aphanidermatum and P. myriotylum were inoculated onto 15 nongrafted watermelon, citron (Citrullus amarus), bottle gourd (Lagenaria siceraria), and interspecific hybrid squash (Cucurbita maxima × C. moschata) cultivars in a growth chamber. Watermelon was more susceptible than bottle gourd and interspecific hybrid squash at 20 and 30°C. Twenty-one cultivars were inoculated in a field with an equal blend of both Pythium species. Interspecific hybrid squash was less susceptible than bottle gourd and watermelon in 2018 and 2019. Seedless watermelon cultivar Tri-X 313 was grafted to one citron, one bottle gourd, and three interspecific hybrid squash rootstocks. Plants were inoculated in the field as described. Grafting to interspecific hybrid squash rootstocks reduced disease incidence compared with nongrafted controls in 2018 and 2019. Mefenoxam and propamocarb applied at transplanting did not affect disease compared with non-fungicide-treated plots. Grafting to interspecific hybrid squash Camelforce significantly increased total and marketable fruit numbers and total weight in 2019 compared with the nongrafted control. In summary, interspecific hybrid squash was consistently resistant to Pythium, demonstrating resistance and utility in watermelon grafting.

Download Full-text

Absorption, Translocation, and Metabolism of14C-Glufosinate in Glufosinate-Resistant Corn, Goosegrass (Eleusine indica), Large Crabgrass (Digitaria sanguinalis), and Sicklepod (Senna obtusifolia)

Weed Science ◽

10.1614/ws-08-089.1 ◽

2009 ◽

Vol 57 (1) ◽

pp. 1-5 ◽

Cited By ~ 23

Author(s):

Wesley J. Everman ◽

Cassandra R. Mayhew ◽

James D. Burton ◽

Alan C. York ◽

John W. Wilcut

Keyword(s):

Weed Species ◽

Digitaria Sanguinalis ◽

Eleusine Indica ◽

Leaf Stage ◽

Senna Obtusifolia ◽

Harvest Timing ◽

Treated Leaf ◽

Harvest Intervals ◽

Corn Plants ◽

Large Crabgrass

Greenhouse studies were conducted to evaluate14C-glufosinate absorption, translocation, and metabolism in glufosinate-resistant corn, goosegrass, large crabgrass, and sicklepod. Glufosinate-resistant corn plants were treated at the four-leaf stage, whereas goosegrass, large crabgrass, and sicklepod were treated at 5, 7.5, and 10 cm, respectively. All plants were harvested at 1, 6, 24, 48, and 72 h after treatment (HAT). Absorption was less than 20% at all harvest intervals for glufosinate-resistant corn, whereas absorption in goosegrass and large crabgrass increased from approximately 20% 1 HAT to 50 and 76%, respectively, 72 HAT. Absorption of14C-glufosinate was greater than 90% 24 HAT in sicklepod. Significant levels of translocation were observed in glufosinate-resistant corn, with14C-glufosinate translocated to the region above the treated leaf and the roots up to 41 and 27%, respectively. No significant translocation was detected in any of the weed species at any harvest timing. Metabolites of14C-glufosinate were detected in glufosinate-resistant corn and all weed species. Seventy percent of14C was attributed to glufosinate metabolites 72 HAT in large crabgrass. Less metabolism was observed for sicklepod, goosegrass, and glufosinate-resistant corn, with metabolites composing less than 45% of detectable radioactivity 72 HAT.

Download Full-text

Influence of Selected Fungicides on Efficacy of Clethodim and 2,4-DB

Peanut Science ◽

10.3146/ps11-14.1 ◽

2012 ◽

Vol 39 (2) ◽

pp. 121-126 ◽

Cited By ~ 1

Author(s):

Gurinderbir S. Chahal ◽

David L. Jordan ◽

Barbara B. Shew ◽

Rick L. Brandenburg ◽

James D. Burton ◽

...

Keyword(s):

North Carolina ◽

Sampling Interval ◽

Palmer Amaranth ◽

Amaranthus Palmeri ◽

Solution Ph ◽

Affect Control ◽

Solution Preparation ◽

Positive Correlations ◽

Sampling Times ◽

Large Crabgrass

Abstract A range of fungicides and herbicides can be applied to control pests and optimize peanut yield. Experiments were conducted in North Carolina to define biological and physicochemical interactions when clethodim and 2,4-DB were applied alone or with selected fungicides. Pyraclostrobin consistently reduced large crabgrass [Digitaria sanguinalis (L.) Scop.] control by clethodim. Chlorothalonil and tebuconazole plus trifloxystrobin reduced large crabgrass control by clethodim in two of four experiments while prothioconazole plus tebuconazole and flutriafol did not affect control. Palmer amaranth [Amaranthus palmeri S. Wats] control by 2,4-DB was not affected by these fungicides. Although differences in spray solution pH were noted among mixtures of clethodim plus crop oil concentrate or 2,4-DB and fungicides, the range of pH was 4.40 to 4.92 and 6.72 to 7.20, respectively, across sampling times of 0, 6, 24, and 72 h after solution preparation. Permanent precipitates were formed when clethodim, crop oil concentrate, and chlorothalonil were co-applied at each sampling interval. Permanent precipitates were not observed when clethodim and crop oil concentrate were included with other fungicides or when 2,4-DB was mixed with fungicides. Significant positive correlations were noted for Palmer amaranth control by 2,4-DB and solution pH but not for clethodim and solution pH.

Download Full-text

Critical Period for Palmer Amaranth (Amaranthus palmeri) Control in Pickling Cucumber

Weed Technology ◽

10.1017/wet.2018.58 ◽

2018 ◽

Vol 32 (5) ◽

pp. 586-591

Author(s):

Samuel J. McGowen ◽

Katherine M. Jennings ◽

Sushila Chaudhari ◽

David W. Monks ◽

Jonathan R. Schultheis ◽

...

Keyword(s):

North Carolina ◽

Critical Period ◽

Relative Yield ◽

Field Studies ◽

Palmer Amaranth ◽

Amaranthus Palmeri ◽

Marketable Yield ◽

Yield Data ◽

Pickling Cucumber ◽

Cucumber Yield

AbstractField studies were conducted in North Carolina to determine the critical period for Palmer amaranth control (CPPAC) in pickling cucumber. In removal treatments (REM), emerged Palmer amaranth were allowed to compete with cucumber for 14, 21, 28, or 35 d after sowing (DAS) in 2014 and 14, 21, 35, or 42 DAS in 2015, and cucumber was kept weed-free for the remainder of the season. In the establishment treatments (EST), cucumber was maintained free of Palmer amaranth by hand removal until 14, 21, 28, or 35 DAS in 2014 and until 14, 21, 35, or 42 DAS in 2015; after this, Palmer amaranth was allowed to establish and compete with the cucumber for the remainder of the season. The beginning and end of the CPPAC, based on 5% loss of marketable yield, was determined by fitting log-logistic and Gompertz equations to the relative yield data representing REM and EST, respectively. Season-long competition by Palmer amaranth reduced pickling cucumber yield by 45% to 98% and 88% to 98% during 2014 and 2015, respectively. When cucumber was planted on April 25, 2015, the CPPAC ranged from 570 to 1,002 heat units (HU), which corresponded to 32 to 49 DAS. However, when cucumber planting was delayed 2 to 4 wk (May 7 and May 21, 2014 and May 4, 2015), the CPPAC lasted from 100 to 918 HU (7 to 44 DAS). This research suggested that planting pickling cucumber as early as possible during the season may help to reduce competition by Palmer amaranth and delay the beginning of the CPPAC.

Download Full-text

Weed Seed Response to Methyl Isothiocyanate and Metham

Weed Science ◽

10.1017/s0043174500067357 ◽

1986 ◽

Vol 34 (4) ◽

pp. 520-524 ◽

Cited By ~ 31

Author(s):

John R. Teasdale ◽

Ray B. Taylorson

Keyword(s):

Laboratory Experiments ◽

Weed Seed ◽

Digitaria Sanguinalis ◽

Methyl Isothiocyanate ◽

Delayed Germination ◽

Sodium Methyldithiocarbamate ◽

Sublethal Concentrations ◽

Metham Sodium ◽

Large Crabgrass

Methyl isothiocyanate (MIT) consistently killed large crabgrass [Digitaria sanguinalis(L.) Scop. # DIGSA] seed at concentations of 4.0 mM or greater. Concentrations of 0.6 to 1.0 mM MIT delayed germination of large crabgrass seed but ultimately allowed the majority of seed to germinate. Dormant large crabgrass seed were killed at concentrations of MIT similar to those required to kill nondormant seed. MIT stimulated germination of dormant large crabgrass seed at sublethal concentrations (0.1 to 1.0 mM). Experiments with metham (sodium methyldithiocarbamate) in the greenhouse and field (metham rapidly degrades to MIT in soils) confirmed results of laboratory experiments with MIT.

Download Full-text

Reduced Preemergence Herbicide Rates for Large Crabgrass (Digitaria sanguinalis) Control in Six Tall Fescue (Festuca arundinacea) Cultivars

Weed Technology ◽

10.1017/s0890037x00024106 ◽

1995 ◽

Vol 9 (4) ◽

pp. 716-723 ◽

Cited By ~ 2

Author(s):

B. Jack Johnson ◽

Robert N. Carrow

Keyword(s):

Field Experiment ◽

Tall Fescue ◽

Festuca Arundinacea ◽

Digitaria Sanguinalis ◽

Made In ◽

Large Crabgrass

A field experiment was conducted over a 2-yr period to determine the effects of reduced PRE herbicide rates on large crabgrass infestation in six tall fescue cultivars. With the exception of oryzalin and benefin plus oryzalin in 1993, there was no cultivar by herbicide interaction for large crabgrass infestation when final ratings were made in 1993 and 1994. This interaction was caused by moderate to severe turfgrass injury that thinned the turf. When cultivars were disregarded, prodiamine was the only herbicide applied at one-third recommended rate in 1993 that effectively suppressed large crabgrass for the full season. Prodiamine and dithiopyr were the only PRE herbicides applied at one-third recommended rates for two consecutive years that effectively suppressed large crabgrass in 1994. Two-thirds recommended rate was needed for two consecutive years for oxadiazon, pendimethalin, oryzalin, benefin plus oryzalin, and benefin plus trifluralin to maintain optimum large crabgrass suppression in 1994.

Download Full-text

Effects of Three Fertilization Methods on Weed Growth and Herbicide Performance in Soilless Nursery Substrates1

Journal of Environmental Horticulture ◽

10.24266/0738-2898-36.4.133 ◽

2018 ◽

Vol 36 (4) ◽

pp. 133-139

Author(s):

Cody J. Stewart ◽

S. Christopher Marble ◽

Brian E. Jackson ◽

Brian J. Pearson ◽

P. Christopher Wilson

Keyword(s):

Fertilizer Treatment ◽

Fertility Rates ◽

Weed Species ◽

Fertilizer Placement ◽

Digitaria Sanguinalis ◽

Fertilizer Rate ◽

Weed Growth ◽

Eclipta Prostrata ◽

Preemergence Herbicides ◽

Large Crabgrass

Abstract Research objectives were to determine the effect of fertilization method (incorporation, subdress, and topdress) on weed growth and the performance of preemergence herbicides applied to soilless substrates. Nursery containers were filled with a pine bark:peat substrate and fertilized at two different rates [4.4 and 9.5 kg.m−3 (8.9 and 19.2 lb.yd−3)] via topdressing, subdressing, or incorporating. Containers were treated with either dimethenamid-P for spotted spurge (Euphorbia maculata L.), flumioxazin for eclipta (Eclipta prostrata L.) or prodiamine for large crabgrass (Digitaria sanguinalis L.). A control was established for each fertilizer rate/placement and weed species that was not treated. Incorporating or subdressing fertilizer resulted in reduced large crabgrass and spotted spurge growth in non-treated containers. Weeds grew larger at the higher fertility rates in both topdress and incorporated treatments but fertilizer rate did not affect growth of spotted spurge or large crabgrass when fertilizers were subdressed. Herbicides generally provided commercially acceptable weed control regardless of fertilizer treatment, but results varied with species. Results suggest that in the absence of herbicides, topdressing may result in greater weed growth compared with subdressing or incorporating fertilizers; however, fertilizer placement will have less impact on herbicide performance if proper herbicides are chosen and applied correctly. Index words: topdress, subdress, incorporate, large crabgrass, eclipta, spotted spurge, preemergence Chemicals used in this study: Flumioxazin (SureGuard®); 2-[7-fluoro-3,4-dihydro-3-oxo-4-(2-propynyl)-2H-1,4-benzoxazin-6-yl]-4,5,6,7-tetrahydro-1H-isoindole1,3(2H)-dione; Dimethenamid-P (Tower) 2-chloro-N-[(2,4-dimethyl-3-thienyl)-N-(2-methoxy-1-methylethyl)acetamide; Prodiamine (Barricade) 2,4-dinitro-N3, N3-dipropyl-6-(trifluoromethyl)-1,3-benzenediamine (Barricade®) Species used in this study: Large crabgrass (Digitaria sanguinalis L.); Eclipta (Eclipta prostrata L.); Spotted spurge (Euphorbia maculata L.)

Download Full-text

Fusarium oxysporum f.sp. niveum. [Distribution map].

Distribution Maps of Plant Diseases ◽

10.1079/dmpd/20113091536 ◽

2011 ◽

Author(s):

Keyword(s):

North Carolina ◽

South Carolina ◽

New Mexico ◽

Fusarium Oxysporum ◽

Citrullus Lanatus ◽

Uttar Pradesh ◽

Distribution Map ◽

Federated States Of Micronesia ◽

New Distribution ◽

Distribution In Europe

Abstract A new distribution map is provided for Fusarium oxysporum f.sp. niveum W.C. Snyder & H.N. Hansen. Ascomycota: Hypocreales. Hosts: watermelon (Citrullus lanatus). Information is given on the geographical distribution in Europe (Bulgaria, Croatia, Cyprus, Greece, Mainland Greece, Hungary, Italy, Montenegro, Poland, Serbia, Spain, Mainland Spain, UK, Ukraine), Asia (Armenia, Azerbaijan, Bangladesh, China, Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hebei, Heilongjiang, Henan, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Nei Menggu, Ningxia, Qinghai, Shaanxi, Shandong, Sichuan, Xinjiang, Yunnan, Zhejiang, India, Karnataka, Punjab, Rajasthan, Uttar Pradesh, Iran, Iraq, Israel, Japan, Korea Republic, Malaysia, Sabah, Pakistan, Philippines, Taiwan, Turkey, Vietnam), Africa (Egypt, South Africa, Tunisia), North America (Canada, Alberta, British Columbia, Manitoba, Ontario, Quebec, Mexico, USA, California, Colorado, Delaware, Florida, Georgia, Hawaii, Idaho, Indiana, Iowa, Maryland, Michigan, Mississippi, Montana, New Mexico, North Carolina, Oklahoma, Oregon, South Carolina, Texas, Washington, Wisconsin), Central America and Caribbean (Panama), South America (Argentina, Brazil, Pernambuco, Sao Paulo, Chile), Oceania (Australia, Western Australia, Federated States of Micronesia, New Zealand, Palau).

Download Full-text