Biochemical trapping of unidentified events

Michel Bounias: Université et INRA - Avignon, Laboratoire de Biochimie, B.P.91, F 84140 Montfavet, France, 1990
Use ARROWS to page backward or forward

Imagemap

Page 15

The natural plots obtained from samples collected at D+ 40 (Figs. 5E and 5F) exhibited positive, fairly good correlations. In all cases, leucine and isoleucine parameters are rather similar, without statistically significant differences.

A Positive Correlation Links Glucose to Chlorophyll A Concentrations in Normal Leaves of Barley, (Bounias, 1975).

Here also, using natural units, the concentrations of glucose are positively correlated to those of chlorophyll A, with all samples that can be considered as controls (i.e.,B, G to Q. For N= 9 pairs, p= +0.824 (p= 0.04), and b= 8.98 (sigmab = 3.56). Then, with the 4 most exposed samples of D + 40 (i.e., C, D, E, F), there appears a significantly negative correlation: for N= 4, p= -0.906 (p= 0.06) and b= - 19.6 (sigmab = 5, 3). The low variability of carbohydrate and pigment levels at D+ 730 did not allow a better correlation to be observed because of the gathering of the points in one limited area. However, this basic phenomenon, which was repeatedly found because of stress conditions, was completely reversed in the samples most exposed to the UE (Figure 6). It is noteworthy that, again, exposed samples at D + 4 are well situated at an extreme (lower) part of the control curve.

Discussion and Conclusions

The level of photosynthetic pigments decreased in all samples collected at D+ 4 and D+ 40 near the epicenter of the UE. Then, at D+ 40 only, glucose contents increased. These observations, strengthened by the significant increase of variability at D+ 40 by contrast with D+ 730, are characteristic of an early alteration of the photosynthetic apparatus, maintained and followed by a decrease in glucose utilization. It was doubtful that after a two-year delay, nothing could ever be related to the influence of anything situated at the point corresponding to the epicenter of the trace of the initial event. At this step, one can assert that something actually happened in the studied area.


Fig. 6. Functional relationships between glucose and chlorophyll A concentrations (nmols per mg).
A = control sample (black dot) = distance 1.5 m at D + 4.
B = 4 most exposed samples at D + 40.