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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2023

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Abstract

Soil salinization is a critical environmental issue restricting agricultural production. Deep return of straw to the soil as an interlayer (at 40 cm depth) has been a popular practice to alleviate salt stress. However, the legacy effects of straw added as an interlayer at different rates on soil organic carbon (SOC) and total nitrogen (TN) in saline soils still remain inconclusive. Therefore, a four-year (2015–2018) field experiment was conducted with four levels (i.e., 0, 6, 12 and 18 Mg ha–1) of straw returned as an interlayer. Compared with no straw interlayer (CK), straw addition increased SOC concentration by 14–32 and 11–57% in the 20–40 and 40–60 cm soil layers, respectively. The increases in soil TN concentration (8–22 and 6–34% in the 20–40 and 40–60 cm soil layers, respectively) were lower than that for SOC concentration, which led to increased soil C:N ratio in the 20–60 cm soil depth. Increases in SOC and TN concentrations in the 20–60 cm soil layer with straw addition led to a decrease in stratification ratios (0–20 cm:20–60 cm), which promoted uniform distributions of SOC and TN in the soil profile. Increases in SOC and TN concentrations were associated with soil salinity and moisture regulation and improved sunflower yield. Generally, compared with other treatments, the application of 12 Mg ha–1 straw had higher SOC, TN and C:N ratio, and lower soil stratification ratio in the 2015–2017 period. The results highlighted that legacy effects of straw application as an interlayer were maintained for at least four years, and demonstrated that deep soil straw application had a great potential for improving subsoil fertility in salt-affected soils.

Abstract

A major challenge for plants in a rapidly changing climate is to adapt to rising temperatures. Some plants adapt to temperature conditions by generating an epigenetic memory that can be transmitted both meiotically and mitotically. Such epigenetic memories may increase phenotypic variation to global warming and provide time for adaptation to occur through classical genetic selection. The goal of this study was to understand how warmer temperature conditions experienced during sexual and asexual reproduction affect the transcriptomes of different strawberry (Fragaria vesca) ecotypes. We let four European F. vesca ecotypes reproduce at two contrasting temperatures (18 and 28°C), either asexually through stolon formation for several generations, or sexually by seeds (achenes). We then analyzed the transcriptome of unfolding leaves, with emphasis on differential expression of genes belonging to the epigenetic machinery. For asexually reproduced plants we found a general transcriptomic response to temperature conditions but for sexually reproduced plants we found less significant responses. We predicted several splicing isoforms for important genes (e.g. a SOC1, LHY, and SVP homolog), and found significantly more differentially presented splicing event variants following asexual vs. sexual reproduction. This difference could be due to the stochastic character of recombination during meiosis or to differential creation or erasure of epigenetic marks during embryogenesis and seed development. Strikingly, very few differentially expressed genes were shared between ecotypes, perhaps because ecotypes differ greatly both genetically and epigenetically. Genes related to the epigenetic machinery were predominantly upregulated at 28°C during asexual reproduction but downregulated after sexual reproduction, indicating that temperature-induced change affects the epigenetic machinery differently during the two types of reproduction.

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Abstract

Renting agricultural land is a common practice in many countries. The possibility to rent land provides farmers with increased flexibility in terms of production volume. Land renting may have various effects on farmland management; however, results from studies analysing these are ambivalent. Farmland in the best possible state is a prerequisite for following up ambitions of feeding a growing population through a sustainable agriculture. Decisions regarding investments on farmland are key. The aim of this study is to increase the understanding of which factors are the most important ones for farmers’ decisions about investments on land they rent. We carried out a questionnaire survey followed by a multiple linear regression considering 34 variables. Although variables included in our model come out as significant in explaining investments, a large part of the variation is left unexplained (R2 = 0.22). Our interpretation of this result is that making investments is a complex decision. Non-economic factors impacting on farmers’ investment decisions such as trust or norms may contribute to the unexplained variation, but may only have been captured partly by our variables. Moreover, decisions regarding investments may not only vary among farmers but also among investments made by an individual farmer. The complex nature of the decisions on how to treat rented land makes it challenging for policymakers to develop measures targeted at farmers renting land. However, the finding that farmers are driving longer distances to rented land than they find acceptable deserves political attention. One potential policy implication may be strengthened incentives for land re-allotment. Re-allotment may address increasing distances and potential consequences such as reduced productivity and increased land abandonment. However, the sustainability of a re-allotment process needs to be considered carefully in terms of economic viability, ecological soundness and social responsibility.