1. Zhuo Wei, Jim J. Wang, Negar Tafti, Yili Meng, and Changyoon Jeong,
Microbial Community Response to Different Biochar Amendments in Sugarcane and Rice Soils
Zhuo Wei, Jim J. Wang, Negar Tafti, Yili Meng, and Changyoon Jeong,
School of Plant, Environmental and Soil Sciences, Louisiana State University, Baton Rouge, LA
MORE NOTES! PLEASE READ (Nov. 20th, 2005)
SCNT and Activation Parthenogenesis seems a bit redundant in that the first part kind of describes the technique already and then it is explained again in the figure caption. Also, should we not say that the embryos are destroyed when cells of the ICM are removed?
3) ET means ‘embryo transfer’? What does it mean (from our stand point) that this may be considered a medical advancement. Does that outweigh the concern that they may be instrumentalized or does it imply that the concern will be overshadowed by this “perceived” benefit, ie. could be used to coerce people to subscribe to this method of AR so that science can produce more hES lines? Think it’s not clear what is being said there.
4) Not sure if you actually want to use the example of Meissner and Jaenisch here but I just put in a little argument which I did not think through totally but it’s there for you to work with.
Solutions:
1) Not sure if you just wanted to outline Eggan’s technique here? I assumed so and deleted the rest so it would fit. Do we have to reference on a poster?
(Nov. 19th, 2005)
Zubin, I will just outline quickly here some of the things I noted today and I told you about on the phone:
Lanza abstract says: “The most basic objection to human embryonic stem (ES) cell research is rooted in the fact that ES cell derivation deprives
embryos of any further potential to develop into a complete human being1,2.” Meissner and Jaenisch also makes reference only to destruction.
Is there somewhere we can say that yes this is a pertinent objection but certainly not the only objection and maybe not even the most basic objection. There are two distinctive criteria to satisfy: 1. not destroy the embryo 2. not treat them as instruments (which probably can’t avoid unless avoid embryological source altogether as you suggest). I tried to outline this in “The Moral Status of the Human Embryo”
There is also the issue of viability and “pseudo-embryos”, I think Baylis is wrong to draw the moral demarcation line where she does. She gives examples of what she thinks is non-viable: multipronucleate embryos, parthenogenetically activated eggs without fertilization, numerical/structural chromosomal abnormalities, genetic mutations, poor morphological quality….all of these are morally equivalent to a somatic cell? What do you think? Should this be addressed under 4) if at all? Meissner and Jaenisch are trying to pull the biological artifact fast one too, with their altered nuclear transfer method of turning off the cdx2 gene and thereby producing a non-viable embryo. Can’t be that easy to change the moral status…seems like a façade, especially since might be able to turn it back on in the hESC derived from that embryo. It seems we are intentionally holding it in that non-viable state and how is that any better (or any different) than destroying a viable embryo?
The moral philosopher Mary Warnock of Britain (I read this in the Jasanoff book) managed to created a space of authorized research on embryos by drawing a demarcation line at the 14-day old period when there is the first appearance of a “primitive streak”. This entity was excluded from the boundary of personhood. This seems wrong but I also don’t want to imply in this poster that abortion rights should be rolled back! Hard to reconcile with a permissive abortion law.
Baylis also raises another interesting question (but this may be beyond the scope of this paper)…suppose we achieve hESC production in an ethical manner, what then? Will women be coerced and exploited by this new technology? Will it be costly and benefit only a privileged few? Eugenics? Nevermind the moral status of the embryo, maybe one of these ethical consequences is reason enough not to pursue hESC research.
These are all just things that have come up in the last day, don’t need to incorporate or deal with them totally for this conference but probably for the paper.
Introduction
(a)
(b)
Rice
Sugarcane
Biochar, a product of biomass thermal carbonation under limited oxygen condition, has been used as a soil amendment to improve soil fertility, enhance carbon sequestration, and remediate contaminants. Recent research studies have reported contradicting observations about the effects of biochar applications on soil microbial community structure. While some found that biochar shifts soil microbial community structure through changing soil physicochemical properties and facilitating labile carbon for microorganisms to utilize, others observed that microbes can hardly use carbon source from biochar due to its resistance to biodegradation. In addition, biochars derived from certain feedstocks such pine wood increase the populations of fungi but not bacteria. Clearly, the exact nature of biochar influence on soil microbial communities is still unclear, and additional studies are needed to elucidate the impact of biochar amendment in different soils, especially under different agroecosystems.
Fig.1. Effect of field treatments on total PLFA in rice and sugarcane soils. Letters above bars indicate statistically difference among treatments at α=0.05
Objective
Rice
Sugarcane
Fig. 4, PCA analysis of individual PLFA variance of both rice and sugarcane soils (a), and factor analysis of principal components (b). AB
In this research, we investigated biochar applications in two representative production agroecosystems in Louisiana, rice and sugarcane, respectively, with the aim to evaluate and compare the effects of different biochar applications on soil microbial community changes using phospholipid fatty acid analysis (PLFA).
Results
Biochar applications generally increased total microbial biomass in both rice and sugarcane soils (Fig.1). Biochar amendment tends to greatly increase HFAs group followed by SFAs, MUFAs in rice soil, whereas it only elevated HFAs and branched FAs in sugarcane soil (Fig. 2). This indicates that biochar enhances particularly G- besides the positive impact on the activity of the most microorganisms in rice soil, whereas it affects positively on both G+ and G+ bacteria in sugarcane soil. Biochar application affects little on fungal biomarker polyunsaturated fatty acid 18:2w9,12.
Wood biochar decreased stress indicators, ratios of cyc/precusor from 0.7 to 0.5 and trans/cis from 1.0 to 0.7, respectively, in rice soil, but had little effect in sugarcane soil. This suggests that biochar tend to improve soil quality that help to reduce stress level microorganisms in rice soil. In addition, for both fields, biochar increased terminal branched FAs, which indicates the improvement in nutrient sufficiency and low pollution environment.
PCA analysis showed that cyclopropyl fatty acids (cy17:0, cy19:0), monounsaturated fatty acids (MUFAs)(16:1w9 cis, 18:1w9 trans,18:1w9cis), and terminal branched PLFA groups were more influenced by biochar treatments. Factor analysis clearly showed the separation of two soil systems of rice and sugarcane, and biochar amendment influenced soil microbial community structure more significantly in rice than sugarcane agroecosystem.
Methods and Material
Site Experiments
Two experimental sites with one sugarcane in Duson, LA and the other one rice in Crowley, LA were established. The sugarcane field was applied with sugarcane biochar and wood biochar, while the rice field was applied rice biochar and wood biochar, respectively. At the end of growth season, surface soil (0-15 cm) samples were collected, freeze-dried and grounded to pass through 2 mm sieve before analysis. Samples include two field replications and two lab replications.
PLFA Analysis
Soil samples of 3 grams from each field treatment were extracted using a solvent mixture of ethanol:Chloroform:phosphate buffer (2:1:0.8) and the supernatants were separated by separation funnel overnight. Organic phase of the supernatants was collected and concentrated using N2, followed by dissolving in 0.5 mL chloroform. The sample was then transferred into a preconditioned silicon column and washed with chloroform and acetone, respectively, to remove nonpolar lipid and glycolipid. The polar lipids were collected by eluting the silicon column with methanol, dried under N2, and methylated with KOH-methanol solution. The collected FAMEs were analyzed using a Shimadzu gas chromatograph with C19:0 as internal standard (White, 2012). The quantified FAMEs were categorized into 7 groups: general biomarkers for all microorganisms (14:0, 16:0, 18:0); saturated fatty acid (SFAs) for bacterial (15:0, 17:0, 19:0); cyclopropyl fatty acids ( cy17:0, cy19:0), monounsaturated fatty acids (MUFAs) (16:1w9 cis, 18:1w9 trans, 18:1w9cis), and hydroxyl fatty acids (HFAs) (2OH 12:0, 3OH12:0, 2OH14:0, 3OH 14:0 and 2OH 16:0) for Gram negative bacteria (G-), terminal branched PLFA (i15:0, a15:0, i16:0 and i17:0) for Gram positive bacteria (G+), polyunsaturated fatty acid (PUFAs) 18:2w9,12 for fungi. Two-way ANOVA (SAS 9.4) along with principle component analysis (PCA) and factor analysis (SPSS 24) were performed for statistical analysis. A
Sugarcane
Fig. 2 Effect of field treatments on the ratio of cyclopropyl PLFA (cy17:0+cy19:0) /monounsaturated precursor (16:1cis+18:1cis), and the ratio of 18:1w9 cis/ 18:1w9 trans.
Sugarcane
Rice
Conclusion
PLFA results show biochar applications significantly affect soil microbial community structure. Wood biochar tends to have greater effect than rice and sugarcane residue biochars. An integrated difference of both soil type and production system likely contributed to the differential effect of biochar amendments on soil microbial activity and community structure between rice and sugarcane agroecosystems.
Fig. 3 Effect of field treatments on specific PLFA groups in rice and sugarcane soils.