46 (eds M.C.S. Wopereis et al.) wateror nutrient-limited production levels in a given rice environment. Yield-reducing factors induce yield losses by reducing or hampering growth, including abiotic and biotic factors. Biotic factors include weeds, pests and diseases; abiotic factors include salinity, alkalinity and iron toxicity. Attainable yield (Ya) refers to the yield that can be achieved wi...

Most species reproduce seasonally, even in the tropics where activity occurs year-round. Squamate reptiles provide ideal model organisms to clarify the ultimate (adaptive) reasons for the restriction of reproduction to specific times of year. Females of almost all temperate-zone reptile species produce their eggs or offspring in the warmest time of the year, thereby synchronizing embryogenesis ...

The relationships between cover and AGB for the dominant and widely distributed alpine grasslands on the northern Tibetan Plateau is still not fully examined. The objectives of this study are to answer the following question: (1) How does aboveground biomass (AGB) of alpine grassland relate to plant cover at different spatial scales? (2) What are the major biotic and abiotic factors influencing...

Mangrove forests, important tropical coastal habitats, are in decline worldwide primarily due to removal by humans. Changes to mangrove systems can alter ecosystem properties through direct effects on abiotic factors such as temperature, light and nutrient supply or through changes in biotic factors such as primary productivity or species composition. Despite the importance of mangroves as tran...

High-throughput, culture-independent surveys of bacterial and archaeal communities in soil have illuminated the importance of both edaphic and biotic influences on microbial diversity, yet few studies compare the relative importance of these factors. Here, we employ multiplexed pyrosequencing of the 16S rRNA gene to examine soil- and cactus-associated rhizosphere microbial communities of the So...

Abiotic stresses elicit complex cellular responses. This complexity made many believe for a long time that tolerance to abiotic stresses cannot be experimentally manipulated. Fortunately, this contention has proven wrong in recent years. Considered once to be an arduous task, genetic engineering for increasing tolerance to abiotic stresses has been achieved to an extent. This change has come du...

Abiotic stresses, including drought, salinity, heat, and cold, negatively affect maize (Zea mays L.) development and productivity. To elucidate the molecular mechanisms of resistance to abiotic stresses in maize, RNA-seq was used for global transcriptome profiling of B73 seedling leaves exposed to drought, salinity, heat, and cold stress. A total of 5,330 differentially expressed genes (DEGs) w...

Homeobox transcription factors play critical roles in plant development and abiotic stress responses. In the present study, we raised rice transgenics over-expressing stress-responsive OsHOX24 gene (rice homeodomain-leucine zipper I sub-family member) and analyzed their response to various abiotic stresses at different stages of development. At the seed germination stage, rice transgenics over-...

What makes a community invasible? For over a century ecologists have sought to understand the relative importance of biotic and abiotic factors that determine community composition. The fact that we are still exploring this topic today hints at both its importance and complexity. As the impacts from harmful non-native species accumulate, it has become increasingly urgent to find answers to the ...

Aflatoxins are carcinogenic secondary metabolites produced mainly by Aspergillus flavus during infection of susceptible crops, such as corn. A. flavus infection and subsequent aflatoxin contamination is a serious issue in the southern US, especially during a drought. Field studies demonstrate that reduction of drought stress by irrigation reduces aflatoxin contamination in corn and peanut. Drou...