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.
2019
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
Aim Root growth strategies may be critical for seeding survival and establishment under dry conditions, but these strategies and their plasticity are little known. We aim to document the ability of young grass seedlings to adjust their root system architecture, root morphology and biomass allocation to roots to promote water uptake and survival under progressive drought. Methods Seedlings growing in columns filled with sand and exposed to drought or well-watered controls were repeatedly harvested for determination of biomass fractions, root length, −architecture and -morphology in a greenhouse experiment. Allometric scaling exponents and standardised major axis regression were used to investigate allocation patterns. Results Young seedlings were able to sustain leaf turgor and functions during eight weeks of progressive drought through phenotypic plasticity of the primary root system producing deeper and simpler roots. Biomass allocation to roots decreased or did not respond, and other components of root morphology showed only moderate plasticity. Conclusion Our results suggest that morphological and architectural plasticity of the primary root system may well be key features for dehydration avoidance and survival in grass seedlings under moderate drought when allocation of biomass to roots and development of secondary roots are constrained.
Authors
Fernanda Canassa Fernanda C. N. Esteca Rafael A. Moral Nicolai Vitt Meyling Ingeborg Klingen Italo DelaliberaAbstract
The effect of inoculation of strawberry roots by two entomopathogenic fungal isolates, Metarhizium robertsii (ESALQ 1622) and Beauveria bassiana (ESALQ 3375), on naturally occurring arthropod pests and plant diseases was investigated in four commercial strawberry fields during two growing seasons in Brazil. Three locations represented open-field production while strawberries were grown in low tunnels at the fourth location. Population responses of predatory mites to the fungal treatments were also assessed. Plants inoculated by the fungal isolates resulted in significantly fewer Tetranychus urticae adults compared to control plants at all four locations. The mean cumulative numbers ± SE of T. urticae per leaflet were: M. robertsii (225.6 ± 59.32), B. bassiana (206.5 ± 51.48) and control (534.1 ± 115.55) at the three open-field locations, while at the location with tunnels numbers were: M. robertsii (79.7 ± 10.02), B. bassiana (107.7 ± 26.85) and control (207.4 ± 49.90). Plants treated with B. bassiana had 50% fewer leaves damaged by Coleoptera, while there were no effects on numbers of whiteflies and thrips. Further, lower proportions of leaflets with symptoms of the foliar plant pathogenic fungi Mycosphaerella fragariae and Pestalotia longisetula were observed in the M. robertsii (4.6% and 1.3%)- and B. bassiana (6.1% and 1.3%)-treated plots compared to control plots (9.8% and 3.7%). No effect was seen on numbers of naturally occurring predatory mites. Our results suggest that both isolates tested may be used as root inoculants of strawberries to protect against foliar pests, particularly spider mites, and also against foliar plant pathogenic fungi without harming naturally occurring and beneficial predatory mites.