In input-intensive cropping systems around the world, farmers rarely proactively manage weeds to prevent or delay the selection for herbicide resistance. Farmers usually increase the adoption of integrated weed management practices only after herbicide resistance has evolved, although herbicides continue to be the dominant method of weed control. Intergroup herbicide resistance in various weed species has been the main impetus for changes in management practices and adoption of cropping systems that reduce selection for resistance. The effectiveness and adoption of herbicide and nonherbicide tactics and practices for the proactive and reactive management of herbicide-resistant (HR) weeds are reviewed. Herbicide tactics include sequences and rotations, mixtures, application rates, site-specific application, and use of HR crops. Nonherbicide weed-management practices or nonselective herbicides applied preplant or in crop, integrated with less-frequent selective herbicide use in diversified cropping systems,...

https://bioone.org/journals/weed-technology/volume-20/issue-3/WT-05-084R1.1/Herbicide-Resistant-Weeds-Management-Tactics-and-Practices1/10.1614/WT-05-084R1.1.pdf

Herbicide-Resistant Weeds: Management Tactics and Practices

Populations of wild radish were collected from two fields in the northern Western Australian wheatbelt, where typical herbicide-use patterns had been practiced for the previous 17 seasons within an intensive crop production program. The herbicide resistance status of these populations clearly established that there was multiple-herbicide resistance across many herbicides from at least four modes of action. One population exhibited multiple-herbicide resistance to the phytoene desaturase (PDS)–inhibiting herbicide diflufenican (3.0-fold), the auxin analog herbicide 2,4-D (2.2-fold), and the photosystem II–inhibiting herbicides metribuzin and atrazine. Another population was found to be multiply resistant to the acetolactate synthase–inhibiting herbicides, the PDS-inhibiting herbicide diflufenican (2.5-fold), and the auxin analog herbicide 2,4-D amine (2.4-fold). Therefore, each population has developed multiple-herbicide resistance across several modes of action. The multiple resistance status of ...

https://bioone.org/journals/weed-science/volume-52/issue-1/WS-03-016R/Multiple-herbicide-resistance-across-four-modes-of-action-in-wild/10.1614/WS-03-016R.pdf

Multiple-herbicide resistance across four modes of action in wild radish (Raphanus raphanistrum)

Summary

In 2003, a random survey was conducted across the Western Australian wheatbelt to establish the extent and frequency of herbicide resistance in Raphanus raphanistrum populations infesting crop fields. Five hundred cropping fields were visited, with 90 R. raphanistrum populations collected, representative of populations present in crop fields throughout the Western Australian wheatbelt. Collected populations were screened with four herbicides of various modes of action that are commonly used for the control of this weed. The majority of Western Australian R. raphanistrum populations were found to contain plants resistant to the acetolactate synthase (ALS)-inhibiting herbicide chlorsulfuron (54%) and auxin analogue herbicide, 2,4-D amine (60%). This survey also determined that over half (58%) of these populations were multiple resistant across at least two of the four herbicide modes of action used in the screening. Only 17% of R. raphanistrum populations have retained their initial status of susceptibility to all four herbicides. The distribution patterns of the herbicide-resistant populations identified that there were higher frequencies of resistant and developing resistance populations occurring in the intensively cropped northern regions of the wheatbelt. These results clearly indicate that the reliance on herbicidal weed control in cropping systems based on reduced tillage and stubble retention will lead to higher frequencies of herbicide-resistant weed populations. Therefore, within intensive crop production systems, there is a need to diversify weed management strategies and not rely entirely on too few herbicide control options.

Frequency and distribution of herbicide resistance in Raphanus raphanistrum populations randomly collected across the Western Australian wheatbelt

A review of biological information is provided for Raphanus raphanistrum L. Native to the Mediterranean region, the species is widely introduced and naturalized in temperate regions around the worl...

The biology of Canadian weeds. 132. Raphanus raphanistrum L.

Raphanus raphanistrum is a problematic weed, which has become increasingly difficult to control in Australian cropping regions. In 2010, a random survey was conducted across 14 million ha of the Western Australian grain belt to establish the frequency of herbicide resistance in R. raphanistrum and to monitor the change in resistance levels by comparing results with a previous survey in 2003. Screening R. raphanistrum populations with herbicides commonly used to control this weed revealed that most populations (84%) contained individual plants resistant to the acetolactate synthase-inhibiting herbicide chlorsulfuron, whereas 49% of populations also had plants resistant to the imidazolinone herbicides. Resistance to other mode of action herbicides (2,4-D (76%) and diflufenican (49%)) was also common. Glyphosate, atrazine and pyrasulfotole bromoxynil remained effective on most R. raphanistrum populations. These results demonstrate that resistance to some herbicides has increased significantly since 2003 when the values were 54% for chlorsulfuron and 60% for 2,4-D; therefore, a wide range of weed management options that target all phases of the cropping program are needed to sustain these cropping systems in the future.

https://bioone.org/journals/crop-and-pasture-science/volume-66/issue-10/CP15063/Multiple-herbicide-resistant-wild-radish-Raphanus-raphanistrum-populations-dominate-Western/10.1071/CP15063.pdf

Multiple herbicide-resistant wild radish (Raphanus raphanistrum) populations dominate Western Australian cropping fields

This study documents the first case of triazine resistance in wild radish and the resistance mechanism involved. The high survival (57 to 97%) of the resistant (R) biotype progeny plants treated at a rate four times higher than the commonly recommended rate of simazine or atrazine clearly established that the R biotype plants were resistant to triazines. All the plants of the susceptible (S) biotype plants were killed when treated at half the commonly recommended rate of atrazine (0.5 kg/ha) or simazine (0.25 kg/ha). The dry weight of the S biotype was reduced by 89 to 96% at the commonly recommended rate of atrazine or simazine, while the dry weight of the R biotype plants was reduced by only 36 to 54% even when treated at a rate four times higher than the commonly recommended rate of atrazine or simazine. The growth-reduction–ratio values indicated that the R biotype progeny plants were 105 and 159 times more resistant to atrazine and simazine, respectively, than the S biotype plants. Leaf chlorophyll f...

Triazine Resistance in a Biotype of Wild Radish (Raphanus raphanistrum) in Australia1

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Crop Updates 2000 - Weeds

Recommended Citation Sweetingham, M, Buirchell, B J, French, B, Wahlsten, L, Wtoth, J, Bayliss, K, Cowling, W, Brennan, R F, Dracup, M, Galwey, N, Thomsom, B, Salam, M, Diggle, A, Thomas, G, O'Neill, B, Thackray, D, Walden, K, Shankar, M, Wright, D, Burges, N, Yang, H, You, M P, Bowran, D, Hashem, A, Wilkins, N, Cheam, A, Piper, T, Blackwell, P, Obst, M, Sandison, A, Weeks, C, Hasson, E, Moreschi, L, Glencross, B, Clements, J, Dracup, M, Hall, R, Johnson, S, Ball, M, Sipsas, S, and Petterson, D. (2001), Crop Updates 2001 Lupins. Agriculture Western Australia, Perth. Conference Proceeding.

/pdf/crop-updates-2001-lupins-2pqulsrgre.pdf

Crop Updates 2001 - Lupins

Recommended Citation Borger, C, Hashem, A, Clarke, M, Cheam, A, Walsh, M, Dhammu, H, Lambert, V, Roberts, C, Quartermaine, R, Nicholson, D, Jackson, M, Campbell, B, Moore, J, D'Antuono, M, Matson, P, Newman, P, Peltzer, S, Minkey, D, Powles, S B, Yu, Q, Owen, M, Busi, R, Manalil, S, Smith, L, White, P, Evans, F, Diggle, A, Borger, C, Michael, P, Lee, S, Grima, R, Adam, G, Bell, T, Davies, S, and Riethmuller, G. (2009), Crop Updates 2009 Weeds. Department of Agriculture and Food, Perth. Conference Proceeding.

/pdf/crop-updates-2009-weeds-4tkilijhad.pdf

Crop Updates 2009 - Weeds

/pdf/crop-updates-2010-weeds-2ho1dwnpza.pdf

Aik Cheam

Papers

Triazine Resistance in a Biotype of Wild Radish (Raphanus raphanistrum) in Australia1

Crop Updates 2000 - Weeds

Crop Updates 2001 - Lupins

Crop Updates 2009 - Weeds

Crop Updates 2010 - Weeds