An 'anomalous' negative flux, in which carbon dioxide (CO2) enters rather than is released from the ground, was studied in a saline/alkaline soil. Soil sterilization disclosed an inorganic process of CO2 dissolution into (during the night) and out of (during the day) the soil solution, driven by variation in soil temperature. Experimental and modeling analysis revealed that pH and soil moisture...

The common bean is the most important food legume in the world. We examined the potential of the fungal entomopathogens Beauveria bassiana and Metarhizium anisopliae applied as seed treatments for their endophytic establishment in the common bean. Endophytic colonization in sterile sand:peat averaged ca. 40% higher for fungus treatments and ca. six times higher for volunteer fungi (other fungal...

The purpose of this project was to use and improve current walnut tissue culture methodology to generate plants from somatic embryos and from mature Juglans regia cultivars. Ninty-eight somatic embryo derived plants are now in soil. Fiftyfour of these are derived from the same embryogenic line. Plants from the same line are phenotypically uniform with the exception of 15% which exhibit thickene...

Growing evidence suggests that plant-soil interactions have important implications for plant community composition. However, the role of phylogenetic relatedness in governing interactions between plants and soil biota is unclear, and more case studies are needed to help build a general picture of whether and how phylogeny might influence plant-soil interactions. We performed a glasshouse experi...

Soil organisms influence plant species coexistence and invasion potential. Plant-soil feedbacks occur when plants change soil community composition such that interactions with that soil community in turn may positively or negatively affect the performance of conspecifics. Theories predict and studies show that invasions may be promoted by stronger negative soil feedbacks for native compared wit...

Microbes can have profound effects on their hosts, driving natural selection, promoting speciation and determining species distributions. However, soil-dwelling microbes are rarely investigated as drivers of evolutionary change in plants. We used metabarcoding and experimental manipulation of soil microbiomes to investigate the impact of soil and root microbes in a well-known case of sympatric ...

BACKGROUND Allelopathic functions of plant-released chemicals are often studied through growth bioassays assuming that these chemicals will directly impact plant growth. This overlooks the role of soil factors in mediating allelopathic activities of chemicals, particularly non-volatiles. Here we examined the allelopathic potential of 8-hydroxyquinoline (HQ), a chemical reported to be exuded fro...

Wheat production around the world is severely compromised by the occurrence of "take-all" disease, which is caused by the soil-borne pathogen Gaeumannomyces graminis var. tritici (Ggt). In this context, suppressive soils are those environments in which plants comparatively suffer less soil-borne pathogen diseases than expected, owing to native soil microorganism activities. In southern Chile, w...

It is generally considered that desert ecosystems release CO2 to the atmosphere, but recent studies in drylands have shown that the soil can absorb CO2 abiotically. However, the mechanisms and exact location of abiotic carbon absorption remain unclear. Here, we used soil sterilization, (13)CO2 addition, and detection methods to trace (13)C in the soil of the Mu Us Desert, northern China. After ...

Field experiments were carried out at JUST agricultural research center during 1999-2000 growing season to evaluate the effects of soil amendment with olive mill by-products (Jift) on growth of faba bean and their symbiosis with VA fungi. Soil was amended with Jift at different levels (Jift: Soil; 0:10, 1:9, 2:8, 3:7 and 4:6) and exposed to solarization, methyl bromide and fungicide treatments....