Weed science as a new discipline and its status in some South Asian universities and colleges: examples from Bangladesh, Bhutan, Nepal and Pakistan.

Agriculture is the most important sector of the economy and livelihood in South Asia. Of the many biotic stresses in agriculture, weeds pose a continuous threat and cause considerable yield losses in the major crops. In the past, ample human labour was available for weed management in South Asia. However, in recent years, there has been a steady decline in labour availability in this region due to migration to other better-paying sectors. Thus, farmers are rapidly adopting less labour-intensive, chemical weed control methods. Adoption of chemical control methods requires formal and nonformal education in herbicide mode of action, safety and weed biology. We emphasize that sound formal and nonformal education in weed science is thus a necessity for this region as adoption of herbicides increases. In this paper, we review existing problems with weeds, current weed management options, herbicide use trends and development of curricula in weed science in academic institutions in Bangladesh, Bhutan, Nepal and Pakistan. We emphasize that herbicide resistance management programmes need to be developed before it becomes a major problem in the region.

Addressing Climate Change: What Can Plant Invasion Science and Weed Science Learn From Each Other?

Plant invasion science and weed science, both dealing with harmful plants, have historically developed in separation. This may also be true for how the two fields are addressing the consequences of future climate change. Here, we first conducted a literature survey to explore how researchers in these two disciplines study the effects of climate change, and then identified their characteristic approaches to determine what the disciplines can learn from each other to better understand, predict, and mitigate the outcomes of responses of harmful plants to climate change. Over the past 20 years, we found a much steeper increase in publications dealing with climate change for invasive alien plants (IAP) than for weeds. However, invasion scientists have to date only rarely investigated climate change effects at the local scale, such as on functional traits and population dynamics. In contrast, weed science could benefit from studies at larger scale, such as using a modeling approach to predict changes in weed distributions. Studies assessing the impacts of the target plants on ecosystem properties and on society, and on their management under climate change are important components of weed studies but remain neglected for IAP. This is despite an urgent need, especially because under climate change, abandoned cropland, and areas of high conservation value are facing increasing risk from IAP. We argue that the strengths and diversity of approaches of these two disciplines in studying the effects of climate change are complementary and that closer ties between them would be highly beneficial for both.

Simulation Models on the Ecology and Management of Arable Weeds: Structure, Quantitative Insights, and Applications

In weed science and management, models are important and can be used to better understand what has occurred in management scenarios, to predict what will happen and to evaluate the outcomes of control methods. To-date, perspectives on and the understanding of weed models have been disjointed, especially in terms of how they have been applied to advance weed science and management. This paper presents a general overview of the nature and application of a full range of simulation models on the ecology, biology, and management of arable weeds, and how they have been used to provide insights and directions for decision making when long-term weed population trajectories are impractical to be determined using field experimentation. While research on weed biology and ecology has gained momentum over the past four decades, especially for species with high risk for herbicide resistance evolution, knowledge gaps still exist for several life cycle parameters for many agriculturally important weed species. More research efforts should be invested in filling these knowledge gaps, which will lead to better models and ultimately better inform weed management decision making.

Karakteristik Hasil Tanaman Kedelai Akibat Aplikasi Berbagai Dosis Herbisida Oksifluorfen dan Pendimethalin

Abstrak. Penelitian ini bertujuan untuk mengetahui hasil tanaman kedelai akibat aplikasi herbisida oksifluorfen dan pendimethalin. Penelitian ini telah dilaksanakan dari Mei hingga Agustus 2019 di Desa Rumpeet dan Laboratorium Ilmu Gulma, Fakultas Pertanian, Universitas Syiah Kuala. Desain penelitian ini menggunakaan rancangan acak kelompok faktorial 2 x 5 dengan 3 ulangan. Faktor-faktor yang diteliti adalah jenis herbisida yakni terdapat 2 taraf (Oksifluorfen dan Pendimethalin) dan dosis herbisida yakni terdapat 5 taraf (Kontrol, 0,5, 1, 1,5 dan 2 kg b.a ha-1). Adapun hasil penelitian yang dilakukan oleh peneliti membuktikan bahwa jenis herbisida dan dosis herbisida tidak mempengaruhi peubah jumlah polong per tanaman, berat biji per tanaman, berat 100 biji, dan hasil biji kering. Tidak ditemukan interaksi antara kedua faktor tersebut terhadap peubah yang diamati. Saran untuk selanjutnya perlu dilakukan penelitian mengenai berbagai variasi jenis dan dosis herbisida lainnya terhadap hasil kedelai.Characteristics of Soybean Yields Due to Application of Various Dosages of Herbicides oxyfluorphene and pendimethalinAbstract. This research aims to determine the yield of soybean plants due to the application of oxyfluorphene and pendimethalin herbicides. This research was conducted in May to August 2019 in Rumpeet Village and Weed Science Laboratory, Faculty of Agriculture, Syiah Kuala University. The design used was a Randomized Factorial Block Design 2 x 5 with 3 replications. The factors observed were the type of herbicide consisting of 2 levels (Oxyfluorphene and Pendimethalin) and the dosages of the herbicide consisting of 5 levels (Control, 0,5, 1, 1,5 and 2 kg a.i ha-1). The results of research conducted by researchers prove that the type of herbicide and dosage of herbicide does not affect the number of pods per plant, weight of seeds per plant, weight of 100 seeds, and yield of dried seeds. No interaction was found between these two factors with the observed variables. Suggestions for further research needs to be done on a variety of types and dosages of other herbicides on soybean yields.

Potensi Terang Bulan, Kirinyuh dan Nimba Sebagai Mulsa pada Tanaman Kedelai

Abstrak: Penelitian ini bertujuan mendapatkan jenis dan dosis mulsa gulma terang bulan, kirinyuh dan nimba yang tepat terhadap hasil tanaman kedelai, serta interaksi antara keduanya terhadap hasil tanaman kedelai. Penelitian ini dilaksanakan di Desa Rumpeet Meunasah Manyang, Kecamatan Krueng Barona Jaya, Aceh Besar, serta di Laboratorium Ilmu Gulma, Fakultas Pertanian, Universitas Syiah Kuala, Banda Aceh dari Januari sampai April 2018. Bahan yang digunakan adalah benih kedelai dega-1, yang diperoleh dari Balai Penelitian Tanaman Aneka Kacang dan Umbi (Balitkabi), Malang. Rancangan percobaan yang dilakukan dalam penelitian ini adalah rancangan acak kelompok (RAK) pola faktorial 3 x 4 dengan 3 ulangan. Jenis mulsa tidak berpengaruh terhadap jumlah polong tanaman-1, jumlah biji tanaman-1, bobot biji tanaman-1, bobot 100 butir dan hasil biji kering kedelai. Dosis mulsa organik berpengaruh terhadap jumlah polong tanaman-1 dan hasil biji kering kedelai, Dosis 24 ton ha-1 dapat meningkatkan jumlah polong tanaman-1 dan hasil biji kering. Tidak terdapat interaksi antara jenis dan dosis mulsa gulma. The Potential of Mexican Sunflower, Siam Weed and Neem As Weeds Mulch in Soybean Plants Abstrack: This Study aims to obtain types and the right mulch dosage of mexican sunflower, siam weed and neem for soybean yields, and both interaction to yields. This research was conducted on Teuku Nyak Arief Street, Rumpeet Village Meunasah Manyang, Kreung Barona Jaya districts, Aceh Besar, and in Weed Science Laboratory, faculty of Agriculture, University of Syiah Kuala, Banda Aceh from January to April 2018. The materials used is soybean seeds variety of Dega-1 that collected from Balai Penelitian Tanaman Aneka Kacang dan Umbi (Balitkabi), Malang. This research using Randomized Completely Block Design with Factorial pattern 3 x 4 repeated 3 times. Types of weed mulch has no effects to number of plants pod, number of plants seeds, grains weight, 100 grains weight and dry yields. Weeds mulch dosage has effects to number of pod-1 and dry yields. On 24 tons ha-1 can increase number of pod-1 and dry yields. There is no interaction between weeds type and weed mulch dosage.