Half-Century Ammonia Emissions From Agricultural Systems in Southern Asia: Magnitude, Spatiotemporal Patterns, and Implications for Human Health

Much concern has been raised about the increasing threat to air quality and human health due to ammonia (NH3) emissions from agricultural systems, which is associated with the enrichment of reactive nitrogen (N) in southern Asia (SA), home of more than 60% the world's population (i.e., the people of West, central, East, South, and Southeast Asia). Southern Asia consumed more than half of the global synthetic N fertilizer and was the dominant region for livestock waste production since 2004. Excessive N application could lead to a rapid increase of NH3 in the atmosphere, resulting in severe air and water pollution in this region. However, there is still a lack of accurate estimates of NH3 emissions from agricultural systems. In this study, we simulated the agricultural NH3 fluxes in SA by coupling the Bidirectional NH3 exchange module (Bi-NH3) from the Community Multi-scale Air Quality model with the Dynamic Land Ecosystem Model. Our results indicated that NH3 emissions were 21.3 ± 3.9 Tg N yr-1 from SA agricultural systems with a rapidly increasing rate of ~0.3 Tg N yr-2 during 1961-2014. Among the emission sources, 10.8 Tg N yr-1 was released from synthetic N fertilizer use, and 10.4 ± 3.9 Tg N yr-1 was released from manure production in 2014. Ammonia emissions from China and India together accounted for 64% of the total amount in SA during 2000-2014. Our results imply that the increased NH3 emissions associated with high N inputs to croplands would likely be a significant threat to the environment and human health unless mitigation efforts are applied to reduce these emissions.

CARD9 mutation linked to Corynespora cassiicola infection in a Chinese patient

Corynespora cassiicola is a plant pathogen associated with leaf-spotting disease. The fungus has been found on diverse substrates: leaves, stems and roots of plants; nematode cysts and human skin. It rarely causes human infections. Here we report one case of subcutaneous phaeohyphomycosis caused by C. cassiicola with prominent tissue necrosis in a woman. All of her clinical features pointed towards a genetic linkage. Hence, whole-exome sequencing and Sanger sequencing were performed on this patient. One mutation of CARD9 was detected.

Micromanipulation of male and female gametes ofNicotiana tabacum: II. Preliminary attempts for in vitro fertilization and egg cell culture

This research is part of an attempt to establish an in vitro fertilization system in tobacco to aid in understanding mechanisms of fertilization. Fusions of isolated male and female gametes were induced in a polyethylene glycol solution. Fusion appears similar to that in maize. One nuclear division of both an unfertilized egg cell and a synergid was induced in KM8p medium with 1 mg/l 2,4-dichlorophenoxyacetic acid in a microchamber culture; one cellular division of the egg cell was also induced in the same medium in solid-drop culture. The osmolality of suspension culture feeder cells was critical for the development of these cells. These results indicate that in vitro fertilization is possible in tobacco, which would be the first such system in dicots.

Micromanipulation of male and female gametes ofNicotiana tabacum: I. Isolation of gametes

The isolation of male and female gametes is a precondition for the micromanipulation of flowering plant gametes. To reflect their condition at fertilization, isolated gametes need to be physiologically mature and vigorous. Sperm cells are isolated from pollen tubes grown on cut styles using the "in vivo/in vitro" technique. Embryo sacs are isolated 2 days after anthesis using brief treatments of minimal concentrations of cell-wall-digesting enzymes on ovules of emasculated flowers. Egg cells are then mechanically separated from the embryo sac, allowing unambiguous identification of cells. Two days is usually the minimum required for the pollen tube to penetrate the ovule and effect fertilization in vivo.

[Plant regeneration from hypocotyl protoplasts of Lycium barbarum L]

The hypocotyl protoplasts of Lycium barbarum L. CV. Ningji No. 1 were isolated in an enzyme mixture solution containing 1% cellulase and 1% pectinase. The protoplasts were cultured in KM 8 p liquid medium containing 0.3 mg/L 2,4-D and 0.3 mg/L BA, The first division of regenerated cells occurred 3 days after culture. The small cell clumps could be observed by naked eyes 20 days after culture. 40 days after culture, microcalli of 1-2 mm in size were transferred to MS solid differentiation medium containing 3% sugar, 0.1-0.4 mg/L BA and 0.05-0.1 mg/L NAA. About 30 days after culture on MS solid medium, the calli with shoots were transferred to 1/2 MS medium containing 0.1 mg/L BA and 0.2 mg/L IBA, from which 80% of them differentiated roots and regenerated whole plantlets.