Transgenerational plasticity is adaptive in the wild

Plants exhibit adaptive responses to light, but it is not known whether parental plants transmit environmental cues that elicit adaptive responses in offspring. We show that offspring life history (annual versus biennial) is influenced by the maternal light environment (understory versus light gap). This transgenerational plasticity is adaptive when offspring are grown in their maternal light environment, where seeds typically disperse. Projections of population growth show that plants that are appropriately cued for their light environment through maternal effects have 3.4 times greater fitness than otherwise. Transgenerational plasticity has evolved in response to natural variation in light and provides a flexible mechanism by which sedentary organisms cope with heterogeneous environments.     

Safe at any scale? Food scares,food regulation,and scaled alternatives

The 2006 outbreak of E. coli O157:H7, traced to bagged spinach from California, illustrates a number of contradictions. The solutions sought by many politicians and popular food analysts have been to create a centralized federal agency and a uniform set of production standards modeled after those of the animal industry. Such an approach would disproportionately harm smaller-scale producers, whose operations were not responsible for the epidemic, as well as reduce the agroecological diversity that is essential for maintaining healthy human beings and ecosystems. Why should responses that only reinforce the problem be proffered? We use the framework of accumulation and legitimation to suggest corporate and government motives for concealing underlying problems and reinforcing powerful ideologies of individualism, scientism, and centralizing authority. Food safety (or the illusion of safety) is being positioned to secure capital rather than public welfare. We propose implementing the principle of subsidiarity as a more democratic and decentralized alternative. Because full implementation of this principle will be resisted by powerful interests, some promising intermediate steps include peer production or mass collaboration as currently applied to disease prevention and surveillance, as well as studying nascent movements resisting current food safety regulations.     

Application of seaweed and pruning residue as organic fertilizer to increase soil fertility and vine productivity

Algae have an indisputable role in coastal ecosystems, but their accumulation and uncontrolled proliferation cause severe damage for the local municipalities. Fertilization with seaweed has been shown to increase soil fertility and crop production reducing ultimately the need for inorganic fertilizers. However, contradictory results of the compost effect have been reported. In the present work, we aimed at testing the suitability of three composted algae materials obtained in a previous study as soil amendments for vines. The composted materials consisted of pruning waste (P) and seaweed (S) mixed (henceforth, P2S1, P1S1 and P1S2, referring the number to the ratio of P to S). Overall, we observed an increase in soil organic matter, phosphorus (P) and potassium (K) in the soil treated in comparison with soils with inorganic fertilization. A moderate N soil enrichment (ca. 20%) was also detected. The leaf analysis reflected generally the greatest concentrations of NPK for the organic treatments, but this was remarkable only during the first year after seaweed application. A noticeable improvement in grape production was detected especially with the P1S1 compost without compromising grape quality although a decrease in sucrose content was noted with the compost with higher productivity (e.g. P2S1 and P1S1). This slight sucrose drop could be attributable to a greater water availability mediated by the compost or to a dilution factor of the sucrose content caused by a greater number of berries in those vines. These findings suggest that although monitoring of the long-term effects is needed, the use of seaweed amendments for agriculture could offer a cost-effective method for coastal municipalities to reduce excessive algae debris while also minimizing the impacts of inorganic fertilization.     

Farmed Gilthead Sea Bream (Sparus aurata) by-Products Valorization: Viscera Oil ω-3 Enrichment by Short-Path Distillation and In Vitro Bioactivity Evaluation

This study shows a pilot scale protocol aimed to obtain an omega 3-enriched oil after the processing of farmed gilthead sea bream viscera (SBV); this was oil was tested in vitro for bioactivity, attesting to the possibility to turn waste into profit The quality of the oil, in terms of requirements for animal and human consumption, was assessed by determining some chemical parameters, such as peroxide value (PV), thiobarbituric acid reactive substances (TBARS), ρ-anisidine (ρ-AV) content, total oxidation value (TOTOX), and phospholipids and free fatty acid (%), both in crude viscera oil (CVO) and refined viscera oil (RVO). Among the extraction conditions, the higher CVO yields were obtained at 60 °C for 10 min (57.89%) and at 80 °C for 10 min (67.5%), and the resulting oxidation levels were low when utilizing both extraction conditions. RVO, obtained from CVO extracted at 60 °C, showed the highest quality on the basis of the assessed parameters. The ethyl esters of the total fatty acid (TFA) contents extracted from RVO were enriched in the ω-3 polyunsaturated fatty acid fraction (PUFAE) up to almost 56% via short path distillation (SPD). Antioxidant activities and adipogenic properties were tested in vitro. PUFAE protected 3T3 L1 cells from oxidative stress and exerted an anti-adipogenic effect in Dicentrarchus labrax pre-adipocytes, attesting to the beneficial properties for both farmed fish and human health. These results could stimulate the adoption of solutions aimed to recover and utilize aquaculture by-products at a higher scale, turning “waste into profit” and indicating a strategy to reach more sustainable business models in aquaculture resource utilization according to the principles of the circular economy.     

Influences of water pH,alkalinity and acid additions on growth and nutrient relationships in chrysanthemum morifolium ’bright golden anne‘ 1

Growth of Chrysanthemum morifolium ‘Bright Golden Anne’ was assessed after application of irrigation water containing five alkalinity levels (0, 100, 250, 500, 1000 mg/liter bicarbonate) in a greenhouse study. Irrigation water having alkalinity levels exceeding 500 (week 12)or 1000 (week 6) mg/liter bicarbonate affected plant height and fresh and dry weights. High levels of irrigation water alkalinity altered nutrient availability in the growing medium and plant tissue nutrient content. This was attributed to a rise in growing medium pH. Between 6 and 12 weeks, the critical level of alkalinity in water that altered growing medium nutrient availability and plant growth decreased from 1000 to 500 mg/liter bicarbonate. Acid additions improved plant growth for the water treatment containing 500 mg/liter bicarbonate. Sulfuric acid was the most effective acid treatment.     

Cover crop identity determines root fungal community and arbuscular mycorrhiza colonization in following main crops

Cover crops (CC) can promote nutrient retention and recycling for main crops yet may also promote soilborne pathogens or suppress beneficial root symbionts such as arbuscular mycorrhizal fungi (AMF). We investigated how root fungal communities of main crop are affected by preceding CC monocultures and mixtures and by main crop identity. We expected that AMF abundance and diversity in main crops are promoted by AM-host CC, and suppressed by non-AM-host CC, and that mixtures of CC species can promote beneficial and suppress pathogenic root fungi. Our full-factorial field experiment comprised crop rotation in sand soil with different CC treatments (monocultures of radish [AM non-host], ryegrass, clover, vetch [AM hosts], mixtures of radish + vetch, ryegrass + clover and fallow) and two main crops (oat and endive). At peak crop growth, we investigated the root fungal communities in the main crops using microscopy and high throughput sequencing (Illumina MiSeq). Cover crop identity was of prime importance and CC legacy overruled main crop identity in determining root fungal communities in main crops. Compared with fallow, CC with ryegrass increased AMF colonization and richness in both main crops and of non-AMF in oat. Legacies of ryegrass, ryegrass + clover and vetch resulted in distinct root fungal communities in the main crops, while the legacy of CC with radish were similar to the legacy of fallow. Root fungal community in crops after clover had highest abundance of representative fungal pathogens in contrast with the other CC treatments that resulted in fungal communities where pathogens were scarce. Oppositely to expected, CC mixtures did not enhance fungal symbionts or suppressed pathogens. Overall, fungal communities in roots of the main crops in our field experiment were determined by the preceding CC species in monoculture, rather than by the CC AMF preference or functional group. This research highlights that the choice of CC determines the root fungal community in main crop which may influence crop quality.     

Limitations of farm management data in analyses of decadal changes in SOC stocks in the Danish soil-monitoring network

Changes in soil organic carbon (SOC) storage in agricultural land are an important part of the Land Use, Land-Use Change and Forestry component of national greenhouse gas emission inventories. Furthermore, as climate mitigation strategies and incentives for carbon farming are being developed, accurate estimates of SOC stocks are essential to verify any management-induced changes in SOC. Based on agricultural mineral soils in the Danish soil-monitoring network, we analysed management effects on SOC stocks using data from the two most recent surveys (2009 and 2019). Between 2009 and 2019, the average increase in SOC stock was 1.2 Mg C ha⁻¹ for 0–50 cm despite a loss of 1.2 Mg C ha⁻¹ from the topsoil (0–25 cm), stressing the importance of including deeper soil layers in soil-monitoring networks. Comparing all four national surveys (1986, 1997, 2009, 2019), the mean SOC stock of mineral soils in Denmark appears stable. The change in SOC stock between 2009 and 2019 was analysed in detail in relation to management practices as reported by farmers. We found that the effects of single management factors were difficult to isolate from co-varying factors including soil parameters and that the use of farm management data to explain changes in SOC stocks observed in soil-monitoring networks appears limited. Uncertainty in SOC stock estimates also arises from low sampling frequency and statistical challenges related to regression to the mean. However, repeated stock measurements at decadal intervals still represent a benchmark for the overall development in regional and national SOC storage, as affected by actual farm management.     

Soil carbon dioxide (CO2) fluxes in permanent upslope pasture and downslope riparian buffers with varying vegetation

Background

Riparian buffers are primarily implemented for their water quality functions in agroecosystems. Their location in the agricultural landscape allows them to intercept and process pollutants from immediately adjacent agricultural land. Vegetated riparian buffers recycle soil organic matter, which elevates soil carbon (C), which upon processing, processes and releases carbon dioxide (CO₂). The elevated soil C and seasonally anoxic environments associated with riparian buffers promote denitrification and fermentation, further increasing soil CO₂ production.

Aim

Against this context, a replicated plot-scale experiment was established at North Wyke, UK, to measure the extent of soil CO₂ emissions in permanent pasture served by grass, willow, and woodland riparian buffers, as well as a no-buffer control.

Methods

Soil CO₂ was measured using the static chamber technique in conjunction with soil and environmental variables between June 2018 and February 2019.

Results

Cumulative soil CO₂ fluxes were in the descending order: woodland riparian buffer; 11,927.8 ± 1987.9 kg CO₂ ha^–1 > no-buffer control; 11,101.3 ± 3700.4 kg CO₂ ha^–1 > grass riparian buffer; 10,826.4 ± 2551.8 kg CO₂ ha^–1 > upslope pasture; 10,554.6 ± 879.5 kg CO₂ ha^–1 > willow riparian buffer; 9294.9 ± 1549.2 5 kg CO₂ ha^–1. There was, however, no evidence of significant differences among all treatments of the current study.

Conclusions

Despite the lack of significant differences, the results from our short-term study show that the woodland riparian buffer had relatively larger soil CO₂ emissions than the remainder of the other riparian buffers and the upslope pasture it serves. Our short-term findings may be useful in developing soil CO₂ mitigation strategies through careful selection of riparian buffer vegetation and may be useful in calibrating mechanistic models for simulating such emissions from similar agro systems.