Crop production is a constant battle with weeds, in which weeds, generally, are victorious. Therefore, rather than channeling our efforts into the development of a “silver bullet” to control weeds, the focus should be on sustainable weed management in both natural- and agro-ecosystems. However, sustainable weed management can be a challenge in the context of global climate change. Over the past few decades, global climate change, mostly indicated by phenomena such as increased atmospheric temperature and elevated CO₂ levels, is evident due to human activities and natural events. These phenomena also affect regional/local climate, resulting in significant influences on the agricultural systems of a particular region. Rising CO₂ levels may give comparative advantages to C₃ plants through increased photosynthesis, biomass production and yield, compared to C₄ plants. Plants with C₄ photosynthetic pathways, on the other hand, are likely to benefit more from rising global temperatures than C₃ plants. Thus, the differential responses of C₃ and C₄ plants to climate change may alter crop–weed interactions and competition outcomes, most likely at the expense of the crop. Climate change will likely cause shifts in weed community compositions, their population dynamics, life cycle, phenology, and infestation pressure. Some weed species may go extinct, while some others may become more aggressive invaders. Weeds are, generally, colonizers and have some unique biological traits and ecological amplitudes that enable them to successfully dominate crops in a habitat with changed environmental conditions. Moreover, climate shifts, especially erratic rainfall and drought, may affect herbicide selectivity and efficacy or the success of bio-control agents resulting in an establishment of a mixed and complex population of C₃ and C₄ weed species adding to the complexity of weed management. Although elevated CO₂ levels will stimulate the productivity of major C₃ crops, most troublesome agricultural weeds will likely be more responsive to a rise in CO₂ than crops, and thus may dominate the agro-ecosystem. It is predicted that, as temperature rises, the majority of the C₄ weeds will flourish and will pose serious crop yield losses. Understanding and assessment of the impact of simultaneous changes in multiple climate factors and their complex interactions on crops and weeds are therefore necessary to formulate an adaptive weed management approach and build resilience. Moreover, strategic policies and strong actions need to be taken to reduce the root causes of CO₂ and other greenhouse gas emissions to minimize the impact of climate change on weed biology and management.

To make potato production more sustainable for smallholder farmers, product diversification through processing is critical. On the other hand, the processing sector mandated some stringent standards in order to maintain product quality, hence potato quality evaluations are required for chip processing industries. Specific gravity, starch, reducing sugars, tuber dry matter, and chip color are all important characteristics to consider for processing. This study was designed to find suitable potato varieties with satisfactory attributes for processing chips, in comparison with other processing potato varieties. Keeping this in mind, the study was performed during the winter season of 2019–2020 and 2020–2021 in Bangladesh. Six processing types of potato varieties viz. BARI Alu-25 (Asterix), BARI Alu-28 (Lady Rosetta), BARI Alu-29 (Courage), BARI Alu-68 (Atlantic), BARI Alu-70 (Destiny), and BARI Alu-71 (Dolly) were evaluated for different quality parameters (specific gravity, dry matter, starch content, reducing sugar, chip color, and crispiness). The result of the study showed an ample variation in the studied parameters among the potato varieties. Among the varieties, BARI Alu-28 (Lady Rosetta) and BARI Alu-29 (Courage) were found better for all the quality parameters, such as dry matter, starch, reducing sugar, chip color, and crispiness, and could be recommended for the processing industries.

Weeds are a major constraint to the success of dry-seeded rice (DSR). The main means of managing these in a DSR system is through chemical weed control using herbicides. However, the use of herbicides alone may not be sustainable in the long term. Approaches that aim for high crop competitiveness therefore need to be exploited. One such approach is the use of high rice seeding rates. Experiments were conducted in the aman (wet) seasons of 2012 and 2013 in Bangladesh to evaluate the effect of weed infestation level (partially-weedy and weed-free) and rice seeding rate (20, 40, 60, 80, and 100 kg ha⁻¹) on weed and crop growth in DSR. Under weed-free conditions, higher crop yields (5.1 and 5.2 t ha⁻¹ in the 2012 and 2013 seasons, respectively) were obtained at the seeding rate of 40 kg ha⁻¹ and thereafter, yield decreased slightly beyond 40 kg seed ha⁻¹. Under partially-weedy conditions, yield increased by 30 to 33% (2.0–2.2 and 2.9–3.2 t ha⁻¹ in the 2012 and 2013 seasons, respectively) with increase in seeding rate from 20 to 100 kg ha⁻¹. In the partially-weedy plots, weed biomass decreased by 41–60% and 54–56% at 35 days after sowing and at crop anthesis, respectively, when seeding rate increased from 20 to 100 kg ha⁻¹. Results from our study suggest that increasing seeding rates in DSR can suppress weed growth and reduce grain yield losses from weed competition.

This study was conducted in the laboratory and screenhouse to determine the effects of temperature, light, osmotic stress, salt stress, burial depth, use of crop residues as mulch, depth of flooding, and use of POST herbicides on the emergence, survival, and growth of doveweed. In the light/dark regime, germination was higher at alternating day/night temperatures of 35/25 C (95%) than at 30/20 C (72%), and no germination occurred at 25/15 C. Light strongly influenced germination (95%) and dark completely inhibited germination. No germination occurred at an osmotic potential of −0.8 MPa and a salt concentration of 150 mM and above. The highest germination (91%) was observed from the seeds sown on the soil surface and emergence decreased by 78, 86, and 92% when burial depths were increased to 0.5, 1, and 2 cm, respectively. No seedlings emerged from seeds buried at depths of more than 2 cm. The use of rice residues as mulch significantly reduced the emergence and growth of doveweed seedlings. The amount of residue required to suppress 50% of the maximum biomass was 2.5 t ha⁻¹. Flooding had a more pronounced effect on seedling biomass than seedling emergence. Biomass was reduced by 78, 92, and 96% when flooding depths increased from 0 to 2, 4, and 6 cm, respectively, for the seeds placed on the soil surface, whereas for the seeds buried at 0.5 cm, these values were 78, 100, and 100%. Bentazon (100 g ha⁻¹) and bispyribac-sodium (30 g ha⁻¹) provided 100% control of doveweed when applied at the three-leaf stage. Doveweed control was less than 31% with glyphosate rates up to 2,000 g ha⁻¹. The application of 2,4-D (500 g ha⁻¹) provided 100% control of doveweed even when applied at the seven-leaf stage. The information from this study could help in developing more sustainable and effective integrated weed management strategies for the control of this weed and weeds with similar response in dry-seeded rice systems.