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Journal of Stress Physiology & Biochemistry, Vol. 9 No. 3 2013, pp. 333-344 ISSN 1997-0838 Original Text Copyright © 2013 by Warrier, Jayaraj, Balu
ORIGINAL ARTICLE
Variation in Gas Exchange Characteristics in Clones of Eucalyptus camaldulensis Under Varying Conditions of CO2
Rekha R. Warrier*, R.S.C. Jayaraj and A. Balu
Institute of Forest Genetics and Tree Breeding, (Indian Council of Forestry Research and Education), PB 1061, R.S. Puram Post, Coimbatore-641002, Tamil Nadu, India
*Phone: 0422 2484167 Mobile: +91 94429 18647
*E-Mail: [email protected], [email protected]
Received April 14, 2013
The Institute of Forest Genetics and Tree Breeding, Coimbatore, India has a long term systematic tree improvement programme for Eucalyptus species aimed at enhancing productivity and breeding for trait specific clones. In the process, thirty high yielding clones of Eucalyptus camaldulensis Dehnh. were identified. Carbondioxide enrichment studies in special chambers help in understanding the changes at individual level, and also at physiological, biochemical and genetic level. It also provides valuable information for establishing plantations at different geographic locations. Considerable variations were observed when the selected 30 clones of E. camaldulensis were subjected to physiological studies under elevated CO2 conditions (600 mol mol-1). Ten clones exhibited superior growth coupled with favourable physiological characteristics including high photosynthetic rate, carboxylation and water use efficiency under elevated carbon di oxide levels. Clones with minimal variation in physiological characteristics under elevated levels of CO2 suggest their ability to overcome physiological stresses and adapt to varying climatic conditions.
Key words: Eucalyptus camaldulensis, physiological, elevated CO2, gas exchange.
ORIGINAL ARTICLE
Variation in Gas Exchange Characteristics in Clones of Eucalyptus camaldulensis Under Varying Conditions of CO2
Rekha R. Warrier*, R.S.C. Jayaraj and A. Balu
Institute of Forest Genetics and Tree Breeding, (Indian Council of Forestry Research and Education), PB 1061, R.S. Puram Post, Coimbatore-641002, Tamil Nadu, India
*Phone: 0422 2484167 Mobile: +91 94429 18647
*E-Mail: [email protected], [email protected]
Received April 14, 2013
The Institute of Forest Genetics and Tree Breeding, Coimbatore, India has a long term systematic tree improvement programme for Eucalyptus species aimed at enhancing productivity and breeding for trait specific clones. In the process, thirty high yielding clones of Eucalyptus camaldulensis Dehnh. were identified. Carbondioxide enrichment studies in special chambers help in understanding the changes at individual level, and also at physiological, biochemical and genetic level. It also provides valuable information for establishing plantations at different geographic locations. Considerable variations were observed when the selected 30 clones of E. camaldulensis were subjected to physiological studies under elevated CO2 conditions (600 mol mol-1). Ten clones exhibited superior growth coupled with favourable physiological characteristics including high photosynthetic rate, carboxylation and water use efficiency under elevated carbon di oxide levels. Clones with minimal variation in physiological characteristics under elevated levels of CO2 suggest their ability to overcome physiological stresses and adapt to varying climatic conditions.
Key words: Eucalyptus camaldulensis, physiological, elevated CO2, gas exchange.
Clonal forestry programmes operating on a large scale are mostly with several species in the genus Eucalyptus and a number of clones are being deployed to increase the productivity of this species in India. Eucalyptus are primarily used for making pulp/paper and for charcoal in India. It also finds use as fuel wood, poles, stakes, fence posts, mining timber and particleboard. There exists tremendous
variation with reference to yield, tree form and physiological characteristics in clones of eucalypts. It is well understood that the cumulative growth of a tree is the result of genotypic and environmental effects and their interaction (Cornillon et al., 2002). Use of physiological parameters to assist in the determination of superior genotypes for tree improvement has been in practice (Kramer, 1986).
Evaluation of the behavior of certain physiological parameters can effectively be used to assess the clonal performances under given environmental conditions. Net photosynthesis rate (Pn), transpiration rate (Tr) and total leaf area per plant are the important factors that determine the biomass production and Water Use Efficiency of a species. Variation in Pn, has been reported as determinant of plant productivity in rubber (Nataraja and Jacob, 1999). Significant differences in Pn and stomatal conductance (gs) have been reported to exist in different tree species (Zipperlen and Press, 1996), viz., Eucalyptus camaldulensis (Farrel et al., 1996) Populus (Kalina and Ceulemans,
1997), Azadirachta indica (Kundu and Tigerstedt,
1998) and Hevea brasiliensis (Nataraja and Jacob,
1999).
As tree growth is the end result of the interactions of physiological processes that influences the availability of essential internal resources at meristematic sites, it is necessary to understand how these processes are affected by the environment to appreciate why trees grow differently under various environmental regimes (Kozlowski and Pallardy, 1997). Understanding the impacts of atmospheric CO2 and its response to changes in temperature is critical to improve predictions of plant carbon-exchange with atmosphere (Crous et al., 2011). Variations have been observed under tropical conditions in the responses of tree seedlings to elevated CO2 levels (Varadharajan et al., 2010).
Screening for genetic differences in ecophysiological traits such as net photosynthesis rates, respiration rates and nutritional attributes becomes imperative in a country with varied agro climatic and soil conditions, as the maximum performance potential of a tree species can be
assessed only when data on these aspects are available (Warrier, 2010). Carbon enrichment studies in special chambers help in understanding the changes at individual level, and also at physiological, biochemical and genetic level. Reports on variations in responses of Eucalyptus species to carbon enrichment have been reported by Roden and Ball (1996) and Lima et al., (2003). Considerable variation has been reported in clones of Eucalyptus camaldulensis Dehnh for important physiological characteristics including high photosynthesis, carboxylation efficiency and water use efficiency (Warrier et al., 2009). The objective of the present study was to analyse differences with respect to leaf photosynthetic characteristics in Eucalyptus camaldulensis Dehnh. clones subjected to varying levels of CO2 The information obtained would support designing further tree improvement and breeding strategies, to mitigate effects of climate change.
MATERIALS AND METHODS
The Institute of Forest Genetics and Tree Breeding, Coimbatore, Tamil Nadu (11016' N and 76°58'21"E, 411m MSL) is working towards improvement of Eucalyptus species for the past two decades. First generation provenance trials were established in ten different locations and 100 candidate clones of E. camaldulensis were selected, based on individual tree superiority for height, diameter at breast height and straightness of stem through index selection method. The clonal trials were established in three different locations, viz., Coimbatore (Tamil Nadu), Sathyavedu (Andhra Pradesh) and Kulathupuzha (Kerala). Thirty three clones across all the three trials were selected after comparing them with 10 commercial clones and seed origin plants of Eucalyptus camaldulensis (3 entries) and E. tereticornis (2 entries) to prove
clonal superiority for high productivity. These selected and tested superior clones of E. camaldulensis were subjected to elevated conditions of temperature and CO2 and physiological observations at six months of age were recorded.
Methods: The selected clones were grown inside the open top chambers (OTCs) of 3 m diameter and 10 m height lined with transparent PVC sheets (0.125 mm thickness) with a CO2 levels of 600 mol mol-1. Pure CO2 gas was used for the enrichment. Similarly OTCs were maintained at elevated temperatures (Ambient +4°C) under ambient CO2 (380 mol mol-1). Controls were maintained in open field outside OTCs, with ambient CO2 (380 mol mol-1). CO2 was provided throughout the day and night (24 h period). The experiments were laid in a Complete Randomized Design. The period of CO2 enrichment was 180 days. A software facility called Supervisory Control and Data Acquisition (SCADA) was used to continuosly control, record and display the actual and desired CO2 level, relative humidity and temperature in each OTC by feedback control loop passing through Programmable Logical Controllers (PLC) (Buvaneswaran et al., 2010). The set that was maintained in the open served as the control under ambient conditions while the set maintained inside the chamber under ambient CO2 conditions was used to eliminate the effects of the chamber on the response of the clones.
Measurements of photosynthesis and related parameters: Net photosynthesis rate (Pn), stomatal conductance (gs), intercellular CO2 concentration (Ci) and transpiration rate (E) were measured using a Portable Photosynthesis System, LiCor-6400 (LiCor Instruments, USA). The measurements were taken between 9.30 am and 11.30 am under cloud free
conditions at the end of six months. Observations were recorded from ten ramets per clone for all the physiological parameters. Water use Efficiency (WUE) was also estimated for the clones. Intrinsic water use efficiency was estimated as the ratio of net photosynthesis rate to stomatal conductance (Pn/gs) whereas instantaneous water use efficiency was estimated as the ratio of net photosynthesis rate to transpiration (Pn/E). Intrinsic carboxylation efficiency was derived as the ratio of net photosynthetic rate to intercellular CO2 concentration (Pn/Ci). Intrinsic mesophyll efficiency was estimated as the ratio of intercellular CO2 concentration to stomatal conductance (Ci/gs).
Statistical Analysis: The data were subjected to analysis of variance for completely randomsied design with five replications. A full-factorial multivariate general linear model (GLM) analysis was conducted using SPSS to determine whether there was significant variation in the different gas exchange characteristics between different CO2 conditions within the clones. Post hoc range tests using Waller Duncan t-test was performed to group the significantly different clones.
RESULTS AND DISCUSSION
Table 1 shows the details of effects of elevated temperature and CO2 on the gas exchange characteristics in Eucalyptus species. Information on the interclonal variation existing in net photosynthetic rate, stomatal conductance, intercellular CO2 concentration and transpiration rate and the derived parameters namely intrinsic and instantaneous WUE, intrinsic carboxylation efficiency and intrinsic mesophyll efficiency are given in Tables 2 and 3 respectively.
Reports state that photosynthetic rate varies among the plants belonging to different taxa and
also among the varieties within the same species (Arora and Gupta, 1996). Among the various
parameters, though the primary physiological
parameters were significantly higher for the clones maintained under control conditions, the clones subjected to elevated CO2 showed higher values for the derived parameters under elevated conditions of temperature and CO2 indicating the efficiency of the species to divert water and nutrients for photosynthesis than transpiration. The overall
variation in various gas exchange characteristics in clones of Eucalyptus subjected to conditions of elevated CO2 (Table 1) suggests the species'
inherent ability to assimilate more of CO2 and efficiency of photosynthesis under varying environmental conditions. Eucalyptus have been shown to precisely regulate transpiration rates, via stomatal movements (Bolhar- Nordenkampf, 1987), allowing this genus to take advantage of favourable conditions via enhanced CO2 uptake (Fordyce et al.,1995), especially when exposed to significant seasonal fluctuations (Greenwood et al., 2003).
Clone EC 52 ranked top with reference to the net photosynthesis rate followed by EC 70. Clones EC 9, 10, 19 and 111 exhibited poor photosynthetic rates. The Pn values varied from 0.204 to 7.94^mol m-2 s-1 with a mean of 3.01^mol m-2 s-1 under ambient conditions, 2.51^mol-2 s-1 in chamber control and 2.39 ^mol-2 s-1 under elevated CO2 levels. The photosynthetic rate was observed to reduce under elevated CO2 levels except in clones EC 101, 94, 54, 207 and 75. Palanisamy (1999) reported increase in net photosynthetic rates in Eucalyptus seedlings after eight months of differential CO2 exposure at 800 ppm CO2. In the present study similar observations were recorded in the clonal responses to physiological stresses. Clones 207, 53, 94, 17,54,70,88 and 116 showed
increased rates in chamber conditions under ambient CO2 levels. Clone EC 52 showed the same trend under chamber conditions and under elevated CO2. Clones EC 9, 10, 19 and 111 exhibited poor photosynthetic rates under the different conditions also.
Stomatal conductance varied between 0.008 to 0.264 mol-2 s-1 with a mean of 0.08 mol-2 s-1 under ambient conditions and there was a reduction in the stomatal conductance in eucalyptus when subjected to elevated CO2 conditions. The minimum and the maximum values of gs were recorded by clones EC 52, 53 198, 207 and EC 66, 11 191 respectively. Clone 207 which showed higher gs under ambient and chamber control conditions, exhibited very poor response (almost 300 per cent low) under e CO2 levels.
Among the 30 clones, EC 54, 75, 88 and 94 ranked higher for intercellular CO2 concentration. Clones EC 14, 19, and 188 recorded low values. Both minimum (106.9 ^l-1 )and the maximum (436.6 ^l-1 ) values for transpiration rate (E) were registered under ambient conditions. The intercellular CO2 concentration was 269.26 ^l-1 for ambient, 275.68 ^l-1 for chamber control and 239.22 ^l-1 for eCO2 conditions.
Clones EC 17, 52, 53, 54 and 207 exhibited high transpiration rates (E). Clones EC 9, 19, 66, 124 and 198 recorded low transpiration rates. The E values varied from 0.56 to 6.1 mmol m-2 s-1 with a mean of 2.44 mmol m-2 s-1 under ambient conditions, 1.97 mmol m-2 s-1 in chamber control and 1.66 mmol m-2 s-1 under elevated CO2 . Carbondioxide is an essential substrate in the photosynthetic process and is incorporated in the light-independent reaction of photosynthesis to produce simple sugars (Kramer et al., 2004). For photosynthesis to occur stomata must open to obtain CO2 which
produces an unavoidable trade-off: as CO2 moves into the leaf, water from within the leaf is lost through the open staomata via transpiration (Gutschick,1999). In order to optimize photosynthetic returns the plant must balance CO2 uptake with transpirational losses, thereby trying to maximize carbon gain while minimizing water loss (Givnish, 1978).
The water molecules lost per molecule of carbon fixed by the plant during photosynthesis, is referred to as water use efficiency (Ellsworth,
1999). Intrinsic water use efficiency (Pn/gs) implies the inherent ability of the plant to assimilate CO2 (Ares and Fownes, 1999). A higher value indicates better ability of the plant for carbon assimilation. Intrinsic WUE ranged between 67.7 and 115.2 ^mol mol-1 with a mean of 56.2 ^mol mol-1 for ambient, 31.86 ^l-1 or chamber control and 43.89 ^l-1 for eCO2 conditions.
The maximum values were observed in clones EC 14 and 19. About ten clones registered low values (Table 3). Li (2000) reported that measurement of WUE may be a useful trait for selecting genotypes with improved drought adaptation and biomass productivity under different environmental conditions. Net photosynthesis and related gas exchange parameters have been suggested as early selection criteria to improve the efficiency of tree breeding (Ceulemans et al. 1996). The values ranged from 5.8-330 under varying levels of CO2. It was observed that water stressed Pinus radiata trees had higher WUE (Thompson and Wheeler 1992). Higher intrinsic WUE was associated with productivity in Prosopis glandulosa and Acacia smallii (Polley et al.1996). It is reported that long-term structural and growth adjustments as well as changes in intrinsic WUE are important mechanisms of Acacia koa to
withstand water limitation (Ares and Fownes 1999).
Restricted stomatal opening will result in decreased stomatal conductance, lower transpiration rates and hence, increased plant water use efficiency (Tricker et al, 2005). As a result, the plant may reduce stomatal frequencies under elevated CO2 concentration and maintain equal or increased carbon intake, so the relationship is of an inverse nature (Gregory, 1996; Fernandez et al., 1998). Combined with reduced stomatal opening, conductance and transpiration rates, elevated CO2 concentration also depresses dark respiration rates also leading to increased water use efficiency (Wullschleger et al., 1992; Murray, 1995). Increase in water use efficiency has been found to increase drought tolerance in many plant species, which may allow increased plant distributions (Tyree and Alexander, 1993; Huxman et al., 1998). Whether future increases in plant distribution are realized is dependent upon whether increased water use efficiency will be greater than enhanced transpiration, as a result of global warming (Houghton et al., 1990 & 2001; Crowley, 2000).
Transpiration is one of the major gas exchange related traits associated with plant growth and productivity. In tree species stomatal transpiration contributes more than 90% of total transpiration (Taiz and Zeiger 2002). Instantaneous water use efficiency, the ratio of amount of carbon fixed per unit amount of water lost through transpiration, differed significantly amongst the clones studied (Table 3). Transpiration and photosynthesis are two major gas exchange parameters, which determine WUE of plants. Thirteen clones showed higher values under elevated CO2 levels over ambient conditions. These clones could be the ideal clones for water limited conditions. Kannan Warrier et al.
(2007) found considerable variation with respect to physiological parameters including water use efficiency in 33 clones of Casuarina equisetifolia.
In the present study, clones EC 9,10,14,19,63,66,69,100,111,123,124,187,191 were found to exhibit low water use efficiency. The Pn/Ci ratio explained as the intrinsic carboxylation efficiency (CE) also differed significantly among the clones and the same clones which showed relatively higher WUE had high CE also. These clones might have greater dependency of photosynthesis on mesophyll characters than stomatal characters. This was evident from the comparatively higher intrinsic
mesophyll efficiency values for these clones over those exhibiting higher WUE and CE. Similar observations have been made in rubber (Hevea brasiliensis) (Nataraja and Jacob, 1999) and sandal wood (Arunkumar et al., 2009). Net photosynthesis and related physiological parameters have been suggested as early selection criteria to improve the efficiency of tree breeding (Balasubramanian and Gurumurthi, 2001). The selections made in the study could be potential candidates' for different agroclimatic zones due to their ability to adapt to varied climatic conditions and also for the development of site specific seed orchards.
Table 1. Various gas exchange characteristics in clones of Eucalyptus subjected to conditions of elevated temperature and CO2 at the end of six months
S. No Characteristics Treatments
Control Elevated Temperature Elevated CO2
1 Net Photosynthetic Rate (Pn) (^mol m-2 s-1) 3.01a 2.51ab 2.39b
2 Stomatal Conductance (gs) (mol m-2 s-1) 0.08a 0.05b 0.04b
3 Intercellular CO2 Concentration (Ci) (Hl l-1) 269.26a 275.68a 239.22b
4 Transpiration Rate (E) (mmol m-2 s-1) 2.44a 1.97b 1.66c
5 Intrinsic Water Use Efficiency (^mol mol-1) 56.2a 31.86c 43.89b
6 Instantaneous Water Use Efficiency (^mol mmol-1) 11.4b 29.64a 37.33a
7 Intrinsic Carboxylation Efficiency (nmol m-2 s-1 (nl l-1)-1 0.0145ab 0.0105b 0.0152a
8 Intrinsic Mesophyll Efficiency Hl l-1 (mol m-2 s-1)-1 5619.6b 9828.2a 8512.5a
JOURNAL OF STRESS PHYSIOLOGY & BIOCHEMISTRY Vol. 9 No. 3 2013
SI No. Clone No. Net Photosynthetic Rate (Pn) (pmol m'2 s'1) Sig. Stomatal Conductance (gs) (mol m'2 s'1) Sig. Intercellular C02 Concentration (Ci) (Hi I1) Sig. Transpiration Rate (E) (mmol m'2 s'1) Sig.
A CC EC A CC EC A CC EC A CC EC
1. 7 2.824 2.784 2.488 e-h 0.040 0.056 0.080 c-f 232.0 292.6 285.2 d-f 2.06 1.03 3.31 d-g
2. 9 1.486 1.234 1.148 i 0.020 0.016 0.016 i 213.0 211.3 215.4 ij 0.85 1.17 0.82 i
3. 10 1.502 0.420 1.076 i 0.020 0.044 0.014 g-i 223.4 338.2 221.6 d-g 0.91 1.90 0.78 hi
4. 14 3.230 0.108 2.072 hi 0.022 0.040 0.014 hi 106.9 346.8 116.9 j 1.04 1.74 0.89 hi
5. 17 4.098 5.292 4.312 be 0.146 0.054 0.048 a-c 370.7 245.4 233.7 b-e 5.11 2.08 2.24 a-c
5. 19 1.874 0.204 1.858 i 0.012 0.058 0.014 g-i 112.4 356.3 134.4 j 0.61 1.74 0.94 i
7. 52 7.550 7.940 4.614 a 0.138 0.082 0.038 ab 335.8 240.9 206.4 d-g 4.60 3.29 1.55 a-c
8. 53 3.022 3.838 2.504 d-g 0.160 0.086 0.014 ab 391.8 356.6 137.2 a-d 4.74 3.73 0.64 a-c
9. 54 2.884 5.746 4.348 b-d 0.078 0.116 0.058 a-c 349.5 311.3 284.0 ab 2,96 4.20 2.49 ab
10. 63 3.230 0.204 2.864 g-i 0.046 0.036 0.052 e-i 232.7 340.3 246.2 c-f 1.95 1.69 2.87 d-g
11. 66 2.390 1.066 1.218 hi 0.018 0.034 0.016 i 128.0 308.7 202.3 ij 0.86 1.31 0.98 i
12. 69 4.306 2.040 1.820 e-h 0.072 0.024 0.024 f-i 244.3 193.8 217.2 h-j 2.32 1.60 1.20 f-i
13. 70 4.346 6.920 3.822 b 0.176 0.044 0.038 ab 391.4 164.7 250.2 def 4.57 1.70 1.73 b-e
14. 75 1.792 3.664 5.552 c-e 0.164 0.070 0.050 ab 404.1 348.3 225.6 a 3.44 2.57 2.19 b-d
15. 88 3.354 7.024 2.762 b-d 0.100 0.080 0.050 a-d 377.1 270.4 326.3 a 2,98 3.44 2.10 b-d
16. 94 1.590 4.524 4.116 c-f 0.264 0.062 0.058 d-h 436.6 308.0 245.9 a 3,51 2.46 2.60 b-d
17. 100 4.150 0.976 0.982 6-i 0.062 0.036 0.056 e-i 225.5 301.3 317.8 b-e 2.74 1.91 2.46 c-f
IS. 101 2.288 1.752 2.388 E-i 0.042 0.042 0.052 f-i 274.0 240.6 282.8 d-g 1,26 2.64 1.91 e-h
19. 111 2.062 0.796 1.006 i 0.016 0.048 0.036 f-i 142.7 321.5 289.3 e-i 0.82 2.27 2.18 f-i
20. 115 2.470 0.272 1.662 hi 0.044 0.050 0.018 b-e 247.0 362.9 173.6 d-g 2,07 1.13 1.07 g-i
21. 116 2.748 7.388 1.604 b-e 0.102 0.064 0.046 f-i 381.7 206.1 260.1 b-e 3.67 2.71 2.24 b-d
22. 123 2.506 0.164 2.072 hi 0.032 0.046 0.028 f-i 208.3 342.6 212.4 d-i 1.54 2.11 1.58 f-i
23. 124 2.912 0.890 0.716 hi 0.050 0.008 0.034 f-i 264.4 173.8 318.3 d-i 1,24 0.58 1.38 i
24. 186 3.544 1.934 1.556 f-i 0.082 0.024 0.020 f-i 278.7 198.2 216.2 f-j 2.32 1.86 0.96 f-i
25. 187 2.818 0.916 1.390 hi 0.020 0.048 0.024 f-i 107.8 332.7 236.0 fi-j 0.95 1.49 1.56 hi
26. 188 3.334 0.872 1.950 6-i 0.078 0.010 0.020 d-g 262.7 155.1 158.1 j 2.85 0.56 1.10 E-i
27. 191 3.878 1.316 1.398 f-i 0.066 0.016 0.080 f-i 255.3 188.0 332.6 d-h 2.06 0.90 2.03 f-i
28. 196 1.528 0.562 2.474 hi 0.040 0.016 0.064 g-i 269.5 279.4 302.6 b-e 1.48 1.22 1.26 hi
29. 198 3.832 1.258 0.536 6-i 0.044 0.014 0.030 a 209.8 186.1 337.6 e-i 1.68 0.92 0.80 i
30. 207 2.764 3.116 5.310 c-e 0.176 0.088 0.040 a 400.7 348.7 191.1 a-c 6.10 3.03 1.82 a
340 Variation in Gas Exchange Characteristics...
JOURNAL OF STRESS PHYSIOLOGY & BIOCHEMISTRY Vol. 9 No. 3 2013
SI No. Clone No. Wate ( Intrinsic r Use Efficiency jimol mol1) Sig. Instantaneous Water Use Efficiency (nmol mmol1) Sig. Intrinsic Carboxylation Efficiency (pmol m ; s'1 (ill I1)1 Sig- Intrinsic Mesophyll Efficiency (ill1 (mol m' s'1)1 Sig.
A CC EC A CC EC A CC EC A CC EC
1. 7 67.6 54.7 30.6 g-j 1.40 3.10 0.70 c 0.012 0.012 0.008 e 541.4 598.7 453.2 d-g
2. 9 83.5 77.1 78.2 b-d 1.80 1.10 1.40 c 0.010 0.006 0.004 e 1220 1390.4 1441.7 b
3. 10 76.0 92.5 73.8 f-i 1.70 0.20 1.40 c 0.006 0.001 0.004 e 1137.4 749.3 1790.5 be
4. 14 148.6 275.0 139.9 A 3.10 0.10 2.40 c 0.056 0.001 0.028 de 475.1 878.9 793.8 og
5. 17 97.0 279.0 107.7 K 3.70 10.90 9.60 c 0.010 0.022 0.028 de 342.1 535.9 505,2 e-fi
6. 19 146.9 330.0 125.7 Ab 3.10 0.10 2.00 c 0.022 0.001 0.016 de 833.5 761.1 923.6 b-g
7. 52 16.6 26.2 33.4 K 5.60 10.80 13.40 c 0.024 0.034 0.034 de 250.3 332 525 g
S. 53 79.0 88.0 38.2 K 2.60 3.80 1.80 c 0.010 0.012 0.026 de 352.8 462.1 1185.8 c-g
9. 54 120.0 171.0 190.0 K 4.90 6.70 8.20 c 0.010 0.022 0.016 de 555.4 319.4 499.8 e-g
10. 63 67.9 60.9 55.3 h-j 1.70 0.10 1.00 c 0.016 0.001 0.014 de 598.1 1001.5 512.8 e-g
11. 66 136.9 30.3 80.9 a-c 3.10 0.80 1.30 c 0.020 0.004 0.010 de 682.6 991.5 1327.4 b-f
12. 69 62.0 90.9 7S.6 Cd 1.80 1.20 1.50 c 0.020 0.014 0.008 de 436.1 861.7 2056.6 b-d
13. 70 100.0 41.6 22.7 K 2.70 16.20 10.60 c 0.012 0.044 0.040 de 235.4 386.8 740.9 e.g
14. 75 84.0 12.3 26.7 K 2.00 4.70 12.00 c 0.004 0.010 0.028 de 379.3 772.1 461 d-g
15. 88 12.6 20.9 13.S K 3.50 9.00 5.80 c 0.010 0.024 0.012 de 405.2 341.5 691.7 <?-g
16. 94 52.0 79.0 23.5 K 0.70 7.30 11.10 c 0.004 0.016 0.028 de 182.9 584.4 510.3 ffi
17. 100 70.5 27.2 17.S J 1.50 0.50 0.40 c 0.020 0.001 0.001 de 396.3 843.5 597 c-g
IS. 101 51.6 59.8 44.5 e-j 1.70 0.90 1.20 c 0.008 0.006 0.008 de 745.6 1320.7 550,2
19. 111 126.2 16.5 26.9 e-h 2.60 0.30 0.50 c 0.016 0.001 0.002 de 899.2 691.6 903.4 b-g
20. 115 57.8 5.8 101.2 f-i 1.20 0.20 1.60 c 0.008 0.001 0.012 e-e 876.7 745.6 1008 b-g
21. 116 79.0 29.5 12.3 K 2.90 13.20 6.40 b 0.008 0.038 0.040 b-e 421.5 386.8 615.6 e-g
22. 123 82.8 35.1 77.5 f-i 1.70 0.10 1.40 b 0.012 0.001 0.012 b-e 789.6 758.5 776.4 b-g
23. 124 60.5 103.7 20.8 2.40 1.50 0.50 b 0.010 0.004 0.001 b-e 598.7 4006 973 a
24. 186 42.4 85.7 S1.0 c-e 1.40 1.10 1.60 b 0.012 0.012 0.010 b-e 501 1038.1 1131.8 b-g
25. 187 148.5 19.7 60.0 Cd 3.20 0.60 1.00 b 0.038 0.002 0.004 b-e 478.1 704.7 1147.9 b-g
26. 188 50.5 114.7 115.6 A 1.30 1.50 2.10 b 0.012 0.006 0.018 a-d 512.3 2193.4 815 be
27. 191 60.2 94.9 17.4 e-g 1.90 1.40 0.70 ab 0.016 0.006 0.002 a-C 429.1 1871.4 469.5 b-g
28. 196 48.9 32.9 41.7 lj 1.20 0.50 2.20 ab 0.006 0.001 0.010 ab 854.9 1799.7 512.8 b-e
29. 198 86.8 95.3 16.8 d-f 2.30 1.40 0.70 a 0.018 0.008 0.001 a 493 1538.7 1143.5 b-e
30. 207 50.0 127.0 311.0 K 1.80 4.70 14.20 a 0.004 0.008 0.034 a 235.2 618.8 474.4 e-g
Warrier et al.
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