Browsing by Person "Hilger, Thomas"

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Acrocomia spp.: Neglected crop, ballyhooed multipurpose palm or fit for the bioeconomy? A review
(2021) Vargas-Carpintero, Ricardo; Hilger, Thomas; Mössinger, Johannes; Souza, Roney Fraga; Barroso Armas, Juan Carlos; Tiede, Karen; Lewandowski, Iris
Acrocomia spp., a genus of wild-growing palms in the neotropics, is rapidly gaining interest as a promising multipurpose crop. Diverse products can be derived from various components of the palm, the oils being of highest interest. Acrocomia shows similar oil yield and fatty acid composition to the African oil palm (Elaeis guineensis). It is, however, able to cope with a wider range of environmental conditions, including temporary water scarcity and lower temperatures, thus potentially a more sustainable alternative to its tropical counterpart. Acrocomia’s research history is recent compared to other traditional crops and thus knowledge gaps, uncertainty, and challenges need to be addressed. This review attempts to assess the acrocomia’s preparedness for cultivation by highlighting the state-of-the-art in research and identifying research gaps. Based on a systematic literature search following a value web approach, it (a) provides a comprehensive overview of research topics, (b) shows the development of publication activities over time and the drivers of this development, and (c) compiles main findings to assess the acrocomia’s preparedness for commercial cultivation. Our results confirm its multipurpose characteristic as a potential feedstock for manifold sectors. Research has continued to increase over the last decade, especially on A. aculeata and is driven by the interest in bioenergy. Increasing knowledge on botany has contributed to understanding the genetic diversity and genus-specific biology. This has enabled applied research on seed germination and propagation toward domestication and initial plantation activities, mostly in Brazil. Main research gaps are associated with genotype–environment interaction, planting material, crop management, and sustainable cropping systems. Overall, we conclude that acrocomia is at an early phase of development as an alternative and multipurpose crop and its up-scaling requires the integration of sustainability strategies tailored to location-based social-ecological conditions.
A collaborative, systems approach for the development of biomass-based value webs: The case of the acrocomia palm
(2022) Vargas-Carpintero, Ricardo; Hilger, Thomas; Tiede, Karen; Callenius, Carolin; Mössinger, Johannes; Souza, Roney Fraga; Barroso Armas, Juan Carlos; Rasche, Frank; Lewandowski, Iris
The diversification of biomass resources is key to the transition towards a bioeconomy. Acrocomia spp., a neotropical genus of palms, is an example of plants’ diversity potential for a sustainable bioeconomy. Acrocomia’s adaptability to environments outside rainforests, its specific fruit properties and high yields has generated the interest of researchers and entrepreneurs, triggering its introduction as a multipurpose oil crop. Developing sustainability-oriented and knowledge-based acrocomia value webs requires a collaborative, systems approach from the outset. Fostering an inter- and transdisciplinary dialogue on acrocomia through a participatory workshop with both academic and non-academic actors contributed to this endeavor. This allowed the identification of priorities, knowledge gaps, and stakeholder roles, and served as the basis for the co-creation of a research and development roadmap. Key steps for the introduction of acrocomia include intertwined technical aspects relating to the development of planting material, cultivation systems, processing technologies and applications, market entry, and value web governance aspects. A broad collaboration among scientists, the public and private sectors, farmers, and civil society, is required for the development of acrocomia value webs. The incorporation of sustainability and a consideration of context in the design and development phases are fundamental to fostering the sustainable performance of acrocomia value webs.
Combined effects of drought and soil fertility on the synthesis of vitamins in green leafy vegetables
(2023) Park, Taewan; Fischer, Sahrah; Lambert, Christine; Hilger, Thomas; Jordan, Irmgard; Cadisch, Georg
Green leafy vegetables, such as Vigna unguiculata, Brassica oleraceae, and Solanum scabrum, are important sources of vitamins A, B1, and C. Although vitamin deficiencies considerably affect human health, not much is known about the effects of changing soil and climate conditions on vegetable vitamin concentrations. The effects of high or low soil fertility and three drought intensities (75%, 50%, and 25% pot capacity) on three plant species were analysed (n = 48 pots) in a greenhouse trial. The fresh yield was reduced in all the vegetables as a result of lower soil fertility during a severe drought. The vitamin concentrations increased with increasing drought stress in some species. Regardless, the total vitamin yields showed a net decrease due to the significant biomass loss. Changes in vitamin concentrations as a result of a degrading environment and increasing climate change events are an important factor to be considered for food composition calculations and nutrient balances, particularly due to the consequences on human health, and should therefore be considered in agricultural trials.
Mungbean response to regulated deficit irrigation: a trade‐off between productivity and adaptability?
(2025) Pataczek, Lisa; Hakenberg, Tim; Hilger, Thomas; Nair, Ramakrishnan M.; Schafleitner, Roland; Asch, Folkard; Cadisch, Georg
Water scarcity, elevated temperatures, as well as pests and diseases have been demonstrated to have a detrimental effect on the yield potential of mungbean ( Vigna radiata ). The cultivation of improved mungbean genotypes with regulated deficit irrigation (RDI), a water‐saving irrigation strategy, has been identified as a promising approach to enhance yield stability of the crop and ensure food security. Thus, the purpose of this study was to identify adaptation strategies and possible trade‐offs to drought of mungbean genotypes under deficit irrigation and the effect on yield by investigating in particular assimilate re‐allocation. Four genotypes (NM11, AVMU 1604, AVMU 1635, KPS2) were cultivated in a greenhouse under three treatments of RDI with depletion fractions as a percentage of total available soil water (TAW) of 0.45, 0.65, and 0.8, corresponding to a recommended irrigation schedule, moderate and severe water deficit, respectively. Samples were collected at the flowering and maturity stages, and the dry matter, dry matter partitioning, yield, harvest index, pod harvest index, water use efficiency, and carbon‐13 isotope discrimination to estimate transpiration efficiency were determined. The study found that productivity (i.e., grain yield) was not lowered as a trade‐off of adaptability to water deficit irrigation. The genotypes either did not respond to deficit irrigation (KPS2 and AVMU 1635) in terms of grain yield or exhibited increased remobilisation of assimilates, either from pod walls to seeds (NM11) or from vegetative plant parts to pods/seeds (AVMU 1604), thereby increasing yields by 38% and 52%, respectively, under water deficit. However, the genotype KPS2 demonstrated stable yields and the greatest harvest index/pod harvest index (36%/69%) across all RDI treatments, suggesting superior adaptability to fluctuating water availability and efficient resource allocation, providing a suitable choice for a range of environmental conditions.
Single-strain inoculation of Bacillus subtilis and Rhizobium phaseoli affects nitrogen acquisition of an improved mungbean cultivar
(2024) Pataczek, Lisa; Armas, Juan Carlos Barroso; Petsch, Theresa; Hilger, Thomas; Ahmad, Maqshoof; Schafleitner, Roland; Zahir, Zahir Ahmad; Cadisch, Georg
Plant growth-promoting rhizobacteria (PGPR) increase plant root growth, potentially improving soil nitrogen (N) uptake, and productivity. Legumes, for instance mungbean, could also benefit from a rise in potential infection sites for nodulation, thereby increasing rates of biological N2 fixation (BNF). Consequently, the objectives of this study were (i) to assess whether PGPR had an effect on mungbean root biomass and if that was linked to N accumulation and productivity; (ii) to identify whether multi-strain inoculation showed greater efficacy in increasing N accumulation and overall productivity than single-strain inoculation; (iii) to test whether N acquisition was based on BNF rather than on soil N uptake. Field trials were conducted in two seasons at the University of Agriculture, Faisalabad with mungbean cultivar NM11 and multi-strain inoculation consisting of Rhizobium phaseoli, Bacillus subtilis, and Pseudomonas fluorescens. The strains were tested additionally in the second season as single-strain inoculation. Multi-strain and inoculation with P. fluorescens alone had no effect on root biomass, total plant-N, BNF or soil N uptake. Inoculation with B. subtilis, however, resulted in significantly increased root dry matter (+ 211 kg ha− 1), total dry matter (+ 1.7 t ha− 1), and total plant-N (+ 36 kg ha− 1). Only inoculation with R. phaseoli enhanced BNF (+ 24%). Yield was not affected by any inoculation. The results suggested that total plant-N was based on soil N uptake rather than on BNF and demonstrated that only single strains affected total N accumulation, pointing to antagonistic mechanisms of the strains in a mixed inoculum.
Thermal imaging for assessment of maize water stress and yield prediction under drought conditions
(2022) Pradawet, Chukiat; Khongdee, Nuttapon; Pansak, Wanwisa; Spreer, Wolfram; Hilger, Thomas; Cadisch, Georg
Maize production in Thailand is increasingly suffering from drought periods along the cropping season. This creates the need for rapid and accurate methods to detect crop water stress to prevent yield loss. The study was, therefore, conducted to improve the efficacy of thermal imaging for assessing maize water stress and yield prediction. The experiment was carried out under controlled and field conditions in Phitsanulok, Thailand. Five treatments were applied, including (T1) fully irrigated treatment with 100% of crop water requirement (CWR) as control; (T2) early stress with 50% of CWR from 20 days after sowing (DAS) until anthesis and subsequent rewatering; (T3) sustained deficit at 50% of CWR from 20 DAS until harvest; (T4) late stress with 100% of CWR until anthesis and 50% of CWR after anthesis until harvest; (T5) late stress with 100% of CWR until anthesis and no irrigation after anthesis. Canopy temperature (FLIR), crop growth and soil moisture were measured at 5‐day‐intervals. Under controlled conditions, early water stress significantly reduced maize growth and yield. Water deficit after anthesis had no significant effect. A new combination of wet/dry sponge type reference surfaces was used for the determination of the Crop Water Stress Index (CWSI). There was a strong relationship between CWSI and stomatal conductance (R² = 0.90), with a CWSI of 0.35 being correlated to a 64%‐yield loss. Assessing CWSI at 55 DAS, that is, at tasseling, under greenhouse conditions corresponded best to the final maize yield. This linear regression model validated well in both maize lowland (R² = 0.94) and maize upland fields (R² = 0.97) under the prevailing variety, soil and climate conditions. The results demonstrate that, using improved standardized references and data acquisition protocols, thermal imaging CWSI monitoring according to critical phenological stages enables yield prediction under drought stress.