Comparison between flaming, mowing and tillage weed control in the vineyard: Effects on plant community, diversity and abundance

Non-chemical weed management: Harnessing flame weeding for effective weed control

The goal of the current study was to create and assess the effectiveness of a hand-pulled ergonomically designed flame weeder. The developed weeder was tested in the field at three operating pressures (20, 30 and 40 Psi) and forward speeds (1.00, 1.25 and 1.50 km/h) to study their effects on plant damage, survival rates, weight preservation rates, weed management effectiveness, soil temperatures, and gas and energy consumption. Thereafter, at optimized values of forward speed and operating pressure, a comparative assessment of flame weeding with traditional methods (mechanical and manual weeding) was done in terms of weed control effectiveness, operational time, energy consumption, and cost of operation. Results showed that the optimal performance of the designed flame weeder was achieved when operated at a speed of 1 km/h and an operating pressure of 40 psi. The survival rate, weight preservation rate, weed control efficiency, change in soil temperature, recovery rate, plant damage, gas consumption, and energy consumption were observed to be 27.3 %, 32.5 %, 91.1 %, 40.74 °C, 8.5 %, 2.2 %, 4.05 kg/h, and 2500.24 MJ/ha, respectively, at optimized values of forward speed (1.00 km/h) and operating pressure (40 Psi). The actual field capacity, field efficiency and operating cost of the flame weeder were 0.0755 ha/h, 94.94 %, and 3620.81 ₹/ha, respectively. Hand weeding had the best level of weed control effectiveness, but it was a laborious, time-consuming process. When compared to manual weeding, flame weeding was 50.42 % cheaper and 94.82 % faster.

Glyphosate uses, adverse effects and alternatives: focus on the current scenario in Brazil

Brazil, a global frontrunner in pesticide consumption and sales, particularly glyphosate, appears to be at odds with other countries that increasingly ban these products in their territories. This study gathers the values of Acceptable Daily Intake and Maximum Residue Limits (MRL) in the European Union for dozens of substances and subsequently contrasts them with the corresponding benchmarks upheld in Brazil concerning its predominant crops. Furthermore, this study delves into the toxicity levels and the potential health ramifications of glyphosate on humans through the ingestion of food containing its residues. The findings from this research underscore a notable surge in glyphosate and pesticide sales and usage within Brazil over the past decade. In stark contrast to its European counterparts, Brazil not only sanctioned the sale and application of 474 new pesticides in 2019, but extended the authorization for glyphosate sales while downgrading its toxicity classification. Finally, this review not only uncovers disparities among research outcomes but also addresses the complexities of replacing glyphosate and introduces environmentally friendlier alternatives that have been subject to evaluation in the existing literature.

Herbicide Use in the Era of Farm to Fork: Strengths, Weaknesses, and Future Implications

Climate change mitigation is a major concern of the European Union (EU). In 2019, the EU presented the European Green Deal (EGD), a new environmental strategy that aimed to neutralize climate change by 2050. Within its policy areas, the EGD included the Farm to Fork (F2F) Strategy that aims to reduce pesticide use by 50%, by 2030. This reduction was proposed due to the supposed negative effects of pesticides on the environment and its biota. Among the different pesticide groups (herbicides, fungicides, insecticides, etc.) though, herbicides are perhaps the hardest to reduce. This review aimed to shed light to any factors that might hinder the reduction of herbicide use; thus, the implementation of the Farm to Fork Strategy underlines some of its weaknesses and highlights key points of a viable herbicide reduction-related policy framework. The literature suggests that integrated weed management (IWM) consists perhaps the most suitable approach for the reduction of herbicides in the EU. Even though it is too soon to conclusively assess F2F, its success is not impossible.

Plant functional diversity is affected by weed management through processes of trait convergence and divergence

Weed management involving tillage and/or herbicides has generally led to a decline of plant diversity in agroecosystems, with negative impacts on ecosystem services provision. The use of plant covers has become the predominant alternative in vineyard management, with numerous studies focusing on analyzing the advantages and disadvantages of plant covers compared to the aforementioned management. Although the impacts of weed management on taxonomic diversity have been widely studied, many gaps remain on their effects on plant functional diversity. As plant functional diversity is linked to the delivery of key ecosystem services in agroecosystems, understanding these effects could enable the development of more sustainable practices. From 2008 to 2018, a long-term trial was carried out in a Mediterranean vineyard to assess different agricultural practices. In this article, we examined how weed management, as well as irrigation use, could affect plant functional diversity. Based on 10 functional traits, such as plant height, specific leaf area or seed mass, we measured different indices of functional diversity and used null models to detect processes of trait convergence and divergence. Our results revealed that weed management and irrigation use had a significant effect on plant functional diversity. Mown plots showed the highest functional richness but were functionally convergent, since mowing was a strong functional filter on most of the traits. Tillage also behaved as a functional filter on some vegetative traits, but favored the divergence of certain reproductive traits. Herbicide-treated and irrigated plots showed the highest values of functional divergence by promoting more competitive species with more divergent trait values. The effect of weed management on these community assembly processes was shaped by the use of irrigation in vineyard rows, leading to functional divergence in those vegetative traits related to resource acquisition and seed mass. These results suggest that greater functional diversity may be associated with the bias caused by higher occurrence of competitive species (e.g. Convolvulus arvensis, Sonchus asper) with contrasting values for certain traits. Therefore, since these species are considered harmful to crops, higher plant functional diversity might not be a desirable indicator in agroecosystems.

Linkages between traits and decomposition of weed communities along a soil management and pedoclimate gradient in Mediterranean vineyards

BACKGROUND AND AIMS

Decomposition is a major ecosystem process which improves soil quality. Despite that, only a few studies have analysed decomposition in an agricultural context, while most agrosystems (e.g. vineyards) are facing decreasing soil quality. The objective of this study is to understand the impacts of both pedoclimate and weed management on the mass loss of vineyard weed communities during the early stages of the decomposition process through their functional properties.

METHODS

In 16 Mediterranean vineyards representing both a pedoclimate and a soil management gradient, we measured the mass loss of green above-ground biomass of 50 weed communities during decomposition in standard conditions and key leaf traits of dominant species [e.g. leaf dry matter content (LDMC) and leaf lignin to nitrogen ratio (lignin:N)]. Both the mean [i.e. community-weighted mean (CWM)] and diversity (i.e. Rao index) were computed at the community level. Path analysis was used to quantify the effects of agro-environmental filters on the mass loss of weed communities through their functional properties.

KEY RESULTS

Tillage and mowing filtered more decomposable communities than chemical weeding (16 and 8 % of higher mass loss after 2 months of decomposition). Path analysis selected weed management practice type as the main factor determining mass loss through its effect on functional properties, while soil and climate had minor and no effects, respectively. Chemical weeding favoured communities with higher investment in resistant leaves (e.g. 38 % higher lignin:N, 22 % lower leaf nitrogen content) which resulted in lower mass loss compared with tilled and mowed communities. Mowing favoured communities with 47 % higher biomass and with 46 % higher nitrogen content.

CONCLUSIONS

Weed management significantly influenced weed mass loss, while the pedoclimate had little effect. Our results suggest that mowing is a promising alternative to herbicide use, favouring higher biomass, nitrogen content and decomposability potential of weeds.