Plant-environment interactions (Hoboken, N.J.)最新文献

Controlled environment farming (CEF) systems, including tunnel houses, glasshouses, and vertical farms, are expanding worldwide. As the industry scales, growers need a broader range of crops that are adapted to CEF systems to take full advantage of the potential to increase yields and decrease weather-related risks. Dwarf grapevines (microvines) are ideal candidates for CEF due to their high economic value, phenotype, and phenology. This study aimed to develop propagation protocols, a critical first step for the successful integration of microvines in the CEF market, and to demonstrate the establishment, early growth, first flowering, and fruiting of table grape microvines in a fully indoor, LED-lit, CEF system. An experiment was conducted to investigate the efficiency of clonal propagation of a newly developed microvine variety, which had been bred for the production of seedless table grapes in response to two variables: (a) shoot position of cutting, and (b) length of time of misting exposure (from 3 to 7 weeks). A subset of successfully established plantlets were then transplanted into a hydroponic, CEF system, where their establishment, early growth, flowering, and fruit formation were assessed. Three weeks after cuttings were taken, 83.7% of the cuttings had formed roots, regardless of cutting section or misting treatment, while the remaining 16.7% of cuttings died. The sprouting success was lower with 49.3% of plants forming new leaves after 7 weeks. The highest level of sprouting was observed with cuttings taken from mid-shoot and lower shoot positions and the 5-week misting duration. While the rooting efficiency and survival of green shoot microvine cuttings are very high, further research is needed to increase the frequency of sprouting in the required timeframes to levels that are more acceptable for commercial production. The establishment success of sprouted cuttings after transplanting to hydroponics was 100% and their production and fruit quality were similar regardless of cutting tissue source. The crop cycle from planting to first harvest was 208 days (63 days for plantlet production and 145 days from transplanting to first harvest). The vines began flowering after an average of 33.9 days and the berries went through veraison (i.e., commencement of ripening) after an average of 116 days under the conditions tested. Microvine fruit grown under these conditions contained greater than the minimum total soluble solids content required for the Australian market. We have demonstrated that table grape microvines have potential as a novel crop for CEF systems.

Picophytoplankton are important primary producers, but not always adequately recognized, for example, due to methodological limitations. In this study, we combined flow cytometry and metabarcoding to investigate seasonal and spatial patterns of picophytoplankton abundance and community composition in the Elbe estuary. Due to the mixing of freshwater and seawater and the tidal currents this ecosystem is characterized by typical estuarine features such as salinity gradients and high turbidity. Picophytoplankton (mostly picoeukaryotes such as Mychonastes and Minidiscus) contributed on average 70% (SD = 14%) to the total phytoplankton counts. In summer picocyanobacteria (e.g., Synechococcus) played a more significant role. The contributions of picophytoplankton to the total phytoplankton were particularly high from summer to winter as well as in the mid estuary. However, at salinities of around 10 PSU in the mixing area of freshwater and seawater, the proportion of picophytoplankton was comparably low (average 49%, SD = 13%). Our results indicate that picophytoplankton prevail in the Elbe estuary year-round with respect to cell counts. Picophytoplankton could occupy important niche positions to maintain primary production under extreme conditions where larger phytoplankton might struggle (e.g., at high or low temperature, high turbidity, and in areas with high grazing pressure) and also benefit from high nutrient availability here. However, we did not find evidence that they played a particularly significant role at the salinity interface. Our study highlights the importance of including picophytoplankton when assessing estuarine phytoplankton as has been suggested for other ecosystems such as oceans.

This study investigated the prevalence of scab caused by Elsinoë phaseoli causing yield losses on beans in Kenya. The research focused on common practices and challenges faced by subsistence farmers with the aim of providing insights into scab prevalence, impact, and potential management challenges. A structured questionnaire was employed in a survey conducted in 2022 and 2023, covering major bean-growing regions using a three-stage sampling design. Data from 128 bean farmers included information on farm size, seed sources, cropping systems, awareness of challenges, and pest/disease management practices. Scab prevalence was determined by scouting for symptoms, with a total of 84 farms surveyed in 2021. The incidence of bean scab was confirmed in all surveyed clusters, indicating its widespread occurrence across various agro-ecological zones. Farmers exhibited common practices such as preference for uniform bean seeds (61%), use of uncertified seeds (83%), intercropping (80%), and limited crop rotation. Challenges included disease and pest infestations, with limited diversity in management options. Confirmation of the presence of bean scab in diverse agro-ecological zones emphasizes its importance and the need for further research on its impact and epidemiology. Challenges with crop rotation were evident due to small farm sizes and subsistence-focused farming. The study recommends further research for a comprehensive understanding of the link between increased scab importance and current bean farming practices such as short rotation periods and the use of susceptible varieties. Training programs are also vital to improve farmers' knowledge on safe agro-chemical use, ensuring sustainable constraint management in common bean cultivation in Kenya.

Cissus quadrangularis is a succulent vine that degrades forests where it is not native by growing over trees and causing them to break or by impeding regeneration. Methods for its control have been tried but no satisfactory approach has been found yet. We carried out an experiment to analyze how much desiccation Cissus can endure before losing its ability to grow when rehydrated, using fragments of 0.5, 1, 2, and 3 internodes to test if desiccation tolerance was affected by fragment length. We found that Cissus remains viable after losing up to 80% of its weight, with shorter fragments losing viability (capacity to grow) at 70% weight loss. No fragments sustained viability at 90% water loss, establishing a critical threshold for Cissus desiccation tolerance. Our study also showed that shorter fragments (0.5 internodes) were less viable compared to longer ones (1, 2 or 3 internodes). Cissus has a remarkable tolerance to desiccation. Therefore, management strategies should ensure complete dehydration of Cissus fragments to prevent its regrowth. Reducing fragments to smaller sizes could amplify the effectiveness of control measures by reducing their viability, but risks of increasing propagule numbers should be considered.

Selecting the right rootstock is crucial for successful fruit production and managing both biotic and abiotic stresses in commercial fruit orchards. To enhance the resilience of peach orchards, this study evaluated the physiological and biochemical responses of Prunus spp. rootstocks , 'Flordaguard' and 'MP-29,' under normoxia (sufficient oxygen content) or short-term hypoxia (low-oxygen content) and ambient or high temperature (40°C) in the root zone. Physiological responses measured were net photosynthesis, stomatal conductance, transpiration, intercellular CO₂ concentration, water use efficiency, the leaf chlorophyll index, and the maximum potential quantum efficiency of photosystem II. The leaf concentrations of nitrogen, phosphorus, potassium, magnesium, calcium, sulfur, boron, zinc, manganese, iron, and copper were also analyzed. Reactive oxygen species (ROS) and antioxidants analyzed were superoxide dismutase (SOD) activity, peroxidase (POD) activity, catalase (CAT) activity, ascorbate peroxidase (APX) activity, glutathione peroxidase (GPX) activity, proline content, glycine betaine content (GB), lipid peroxidation (LPO), superoxide (O₂ ^-) concentration, and hydrogen peroxide (H₂O₂) concentration. When subjected to root zone hypoxia or high temperature individually, 'MP-29' performed better physiologically than 'Flordaguard'. However, when root zone hypoxia and high temperature were combined, 'MP-29' performed better biochemically with enhanced antioxidant activity, osmolyte content, and nutrient absorption. Nutrient analysis of leaves revealed that 'MP-29' had higher N, P, K, Ca, and B concentrations than 'Flordaguard'. Consequently, 'MP-29' demonstrated greater tolerance to short-term exposure to the combined effects of high root zone temperature and hypoxia. This research contributes to identifying a suitable rootstock within the Prunus genus able to withstand root zone conditions that often result from severe weather events commonly experienced in Florida and other parts of the world.

Biological Nitrification Inhibition (BNI) encompasses primarily NH₄ ⁺-induced release of secondary metabolites to impede the rhizospheric nitrifying microbes from performing nitrification. The intermediate wheatgrass Thinopyrum intermedium (Kernza®) is known for exuding several nitrification inhibition traits, but its BNI potential has not yet been identified. We hypothesized Kernza® to evince BNI potential through the presence and release of multiple BNI metabolites. The presence of BNI metabolites in the biomass of Kernza® and annual winter wheat (Triticum aestivum) and in the root exudates of hydroponically grown Kernza®, were fingerprinted using HPLC-DAD and GC-MS/MS analyses. Growth bioassays involving ammonia-oxidizing bacteria (AOB) and archaea (AOA) strains were conducted to assess the influence of the crude root metabolome of Kernza® and selected metabolites on nitrification. In most instances, significant concentrations of various metabolites with BNI potential were observed in the leaf and root biomass of Kernza® compared to annual winter wheat. Furthermore, NH₄ ⁺ nutrition triggered the exudation of various phenolic BNI metabolites. Crude root exudates of Kernza® inhibited multiple AOB strains and completely inhibited N. viennensis. Vanillic acid, caffeic acid, vanillin, and phenylalanine suppressed the growth of all AOB and AOA strains tested, and reduced soil nitrification, while syringic acid and 2,6-dihydroxybenzoic acid were ineffective. We demonstrated the considerable role of the Kernza® metabolome in suppressing nitrification through active exudation of multiple nitrification inhibitors.

Functional traits are important in understanding how plants respond and adapt to their immediate environment. Parrotia subaequalis is a highly endangered arbor species found throughout eastern China, primarily inhabiting hillsides and valleys, yet, little is known about the variation in leaf traits across these environments. In the present study, we tested this by comparing leaf surface area, leaf weight, leaf length, leaf symmetry and leaf mass per unit area, as well as the relationship between leaf traits and environmental factors and the scaling relationship between leaf surface area versus leaf dry mass. We observed significant differences in leaf surface area, weight, and length among the population sites, and these variables were strongly affected by environmental factors, especially high mean annual temperatures in hillside habitats and high mean annual precipitation in valley habitats. The scaling exponents remained numerically variant among the 10 populations, with different slopes greater than 1.0, and the scaling exponents increased significantly with hillside habitats. These metrics correlated with soil thickness associated with different habitat types. The areal ratio (AR) values in all populations deviated from 1, indicating that the two lamina sides were asymmetrical. The standardized symmetry index (SI) values displayed significant variation, especially in leaves from hillside habitats with a high degree of asymmetry. Collectively, our findings demonstrated that leaf functional traits exhibit considerable variability in response to different environmental contexts and provide valuable reference data that could be useful for conserving this endangered species.

The Southern African region suffers from drought and food system uncertainty with increased risks due to climate change, natural disasters, and global catastrophes. Increasing crop diversity with more appropriate and resilient crops is an effective way of increasing food system resilience. We focus on crop species that are native or naturalized to an area because of their increased resilience than those that are not naturally occurring. Additionally, crops that are easily stored are more useful in times of drought and disaster. In this systematic review, we use scientific interest in neglected and underutilized species (NUS) from Southern Africa to help define next steps toward their cultivation and development as a marketable crop. We found that although scientific interest is minimal for storable Southern African NUS, these crops are worth scaling up due to their economic and nutritional value. We outline next actionable steps and specific NUS for production in a more agrobiodiverse and resilient agriculture system.

This study examines the critical interaction between seasonal precipitation variability and forest maturity in determining ion deposition patterns in rehabilitated forest ecosystems. This research was conducted in rehabilitated forest sites in Bintulu, Sarawak, Malaysia that had ecologically similar plant distribution, species, and age in each planting area. This facilitated the standardization of rainfall deposition in the different study plots which streamlined the study of these specific facets of ecosystem dynamics. The goal is to understand how seasonal changes and the age of the forest influence the chemical composition of the flux that relates to the movement and deposition of nutrients through the forest ecosystem. This flux is a key factor in the health of the forest ecosystem and nutrient cycling. Using ion exchange resin (IER) samplers, we accurately measured and compared the deposition of different ions (Ca²⁺, Na⁺, Fe²⁺, Cu²⁺, NO₃ ^-, NH₄ ⁺ and SO₄ ^2-) across different seasons and forest ages. The deposition of Ca²⁺ and NH₄⁺ was significantly lower in the low-precipitation season than in the high-precipitation season in all forest stands, regardless of the year they were established (1996, 1999, 2002, 2005, and 2009). In contrast, ions such as Na⁺, Fe²⁺, Cu²⁺, NO₃ ^- and SO₄ ^2- showed no clear seasonal fluctuations. In addition, the study shows that through-fall in forest stands from 2002, 2005 and 2009 had higher concentrations of Ca²⁺ in both seasons than in 1996 and 1999. Interestingly, forest stands from 2009 and 2002 had elevated levels of Na⁺ and SO₄^2- in seasons with low precipitation, while stands from 1996 had higher levels in seasons with high precipitation. Our results emphasize the crucial role of precipitation amount and canopy age in determining ion deposition in forest ecosystems. By demonstrating the significant influence of precipitation seasonality and forest maturity on the chemical composition of throughfall, this study contributes to a deeper understanding of nutrient dynamics in developing forest landscapes and provides valuable insights for ecological restoration measures.

Plant-parasitic nematodes pose a significant threat to finger millet crops, potentially causing yield reduction of up to 70%. Extracts derived from finger millet varieties contain potent bioactive compounds that can mitigate nematode damage and promote plant growth. This study aimed at isolating and characterizing bioactive compounds from the finger millet varieties Ikhulule, Okhale-1, and U-15; evaluating the impact of Ikhulule and U-15 extracts on the mortality of the root lesion nematode Pratylenchus vandenbergae; assessing the growth promotion effects of Ikhulule and U-15 extracts on the finger millet variety Okhale-1; and determining the efficacy of these extracts in managing plant-parasitic nematodes under greenhouse conditions. Extracts were obtained from both leaves and roots and tested in vitro for nematode mortality and in vivo for growth promotion and nematode control. The results showed that finger millet extracts exhibited strong nematicidal properties in vitro, achieving a mortality rate of up to 98% against P. vandenbergae nematodes. Applying these extracts to finger millet shoots significantly reduced nematode populations in both soil and roots and decreased the reproductive factor to below one (1), indicating an effective nematode control. The study attributes the enhanced nematicidal effects of finger millet extracts to their bioactive compounds, particularly dodecanoic acid, phytol, 1,1,4a-trimethyl-6-decahydro naphthalene, 2,3-dihydro-benzofuran, 2-methoxy-4-vinylphenol and ethyl ester, and hexadecanoic acid. These findings suggest that finger millet-derived extracts offer a natural solution for nematode management and broader agronomic benefits, ultimately contributing to overall plant health and productivity.