The 28th APWSS Conference to be held at Phuket, Thailand during 26 to 29 November 2023           |           Weeds-Journal of the APWSS Vol. 4, Issue 2, 2022

Volume-1 | Issue-1 (January-June) | Year 2019

Making a Difference- The New ‘Weeds’ Journal
Nimal R. Chandrasena

KEYWORDS:

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Abstract:

Email

nimal.chandrasena@gmail.com

Address

Current Address: Nature Consulting, 1, Kawana Court, Bella Vista, NSW 2153, Australia
Founders of the Asian-Pacific Weed Science Society – An Appreciation
Nimal R. Chandrasena

KEYWORDS:

Asian-Pacific Weed Science Society, Donald L. Plucknett, William R. Furtick, Roman R. Romanowski Jr.

Abstract:

The APWSS, born on 22 June 1967, is now 52 years old. It is now taking a major step forward by publishing a dedicated, weed science journal - Weeds. In this Special Editorial for the journal’s inaugural issue, I am privileged to have the opportunity to reflect on the landmark events, which preceded the Society’s birth. We were not born by accident; momentous events within the discipline of Weed Science, and related fields, shaped our birth. It is appropriate, in this first issue of the new journal to acknowledge our Society’s gratitude to the three founding fathers. While providing my own views on some important challenges ahead, I recall the essence of what our founding fathers achieved, so the readers might be inspired. We stand tall today because of their vision and commitment, over five decades ago. In 2017, celebrating 50 years of existence as a professional society, we recorded the society’s achievements and contributions to Weed Science and the broad spirit in which they were achieved. Applying Weed Science across the Asian-Pacific and possibly, other tropical regions, must continue to be our goal, while continuing to take up new challenges. This will require APWSS to engage more broadly with similar global movements, by networking to share knowledge and experience to inspire the current and next generation of weed scientists. Given there is little consistency in the way we deal with weeds in the different member countries, developing a common agenda to educate and influence national policies must be a priority for the APWSS in the 21st Century.

Email

nimal.chandrasena@gmail.com

Address

Current Address: Nature Consulting, 1, Kawana Court, Bella Vista, NSW 2153, Australia
Some Thoughts About Ethics for Agriculture
Robert L. Zimdahl

KEYWORDS:

Agriculture, ethics, philosophy, production, values, Weed Science

Abstract:

This paper is a result of a 50-year career in Weed Science, which evolved to study aspects of the moral philosophy and the ethics of Agriculture. It is in many ways a personal story, but it concludes with a plea for careful consideration of the ethics of the agricultural enterprise

Email

r.zimdahl@colostate.edu

Address

Colorado State University, Fort Collins, CO, USA 80524
Broadening the APWSS Horizon in the AsianPacific Region
Kil-Ung Kim

KEYWORDS:

Agriculture, Weed Science, Asian-Pacific region

Abstract:

The major challenge facing the Asian-Pacific Weed Scientists and land managers in the region is to develop the most effective and sustainable weed management approaches for all systems, including agriculture and natural land systems. Whatever weed management approach we develop must be sustainable, in both the short- and long-term and acceptable as safe for the community, wildlife, and the natural environment. Given my previous involvements with the APWSS, in this inaugural issue of the APWSS Journal, I wish to reflect upon how the Society may assist all member countries, particularly, those which are yet to be affiliated to the Society. We are challenged by the rapidly increasing human population in our region, food scarcity, some new weed problems, a changing climate and special issues, such as the development of herbicide resistance, as a result of overuse of herbicides and unsustainable farming practices. What options do we have to meet these challenges? I propose that APWSS must expand its involvement across the region, and to do so, requires a renewed effort to obtain funding from donors for more training, seminars, and conferences on weeds. As our founders expected, we must also develop a programme to assist various governments and agencies of different countries in identifying national needs on weed-related matters and solutions

Email

kukim@knu.ac.kr

Address

Kyungpook National University (KNU), Daegu, South Korea
Taxonomy of Echinochloa (L.) P. Beauv (barnyard grass) in the Asian-Pacific Region: An Update
Peter W. Michael

KEYWORDS:

Echinochloa, barnyard grass, Asian-Pacific grasses

Abstract:

This paper provides a revised key to the identification of taxa of Echinochloa in the Asian-Pacific region, the result of many years’ study of this important weedy genus, with an emphasis on the importance of association with the Asian-Pacific Weed Science Society. Descriptions of two new Indian species are included

Email

pwjemichael@hotmail.com

Address

Current Address: 5, George Street, Epping, NSW 2121, Australia
Biodegradation of topramezone by a Trichoderma Isolate in soil
Partha P. Choudhury Abha Singh and Rajan Singh

KEYWORDS:

Biodegradation, Bioremediation, Herbicide, Topramezone, Trichoderma sp.

Abstract:

Topramezone, a pyrazolone compound, has been introduced in many countries as a post-emergence herbicide. It inhibits 4-hydroxyphenylpyruvate dioxygenase (HPPD), a key enzyme in carotenoid pigment biosysnthesis, in susceptible plants, and can effectively control annual grasses and broadleaf weeds in maize (Zea mays L.), sweet corn (Zea mays convar. Saccharata var. rugosa) and popcorn (Zea mays var. everta). Topramezone is a highly persistent herbicide, which has high mobility in soil, posing a risk of leaching to ground and surface water. Despite its increasing use, not much is known about topramezone degradation and the potential impact of its persistence in the agricultural environment. We investigated the interaction between the herbicide and soil microorganisms in topramezone-treated soil, in order to test its bio-remediation potential particularly by soil fungi, and to elucidate the possible degradation pathways. One microbial strain, capable of transforming topramezone, was isolated from soils treated with the herbicide and identified as a species of Trichoderma, a well-known, common soil organism. The isolate survived in the minimal broth, incorporated with topramezone, at a concentration of 1000 mg/L of the medium. In sterilized soil, spiked with the herbicide, the Trichoderma isolate degraded 85% of the applied topramezone within 30 days of incubation, which is much faster than the reported, standard half-life of the herbicide (about 120 days). Based on the eight breakdown products (I to VIII), which were identified by liquid chromatography-mass spectroscopy (LC-MS) analyses, we propose that the herbicide was degraded by the fungus through various biochemical reactions, viz. demethylation, desulfonylation followed by hydroxylation of the herbicides, alkyl hydroxylation, hydrolysis of the carbonyl group of ketone, methoxylation, and hetero ring hydroxylation. Our results add to previous research that Trichoderma species and its strains are capable of degrading some pesticides, including herbicides in soil. The degradation products identified strongly imply the presence of a substrate recognition mechanism and a corresponding metabolic response system in the Trichoderma isolate, which can effectively degrade topramezone in the agricultural soil.

Email

Partha.Choudhury1@icar.gov.in

Address

ICAR-Directorate of Weed Research, Jabalpur-482004, India; current address: Division of Plant Physiology and Biochemistry, ICAR-Indian Institute of Horticultural Research, Hessaraghatta Lake Post, Bangalore-560089, India