6. Research
Objective
To determine the effects of different soils over
chlorophill, development and growth of native
J. curcas seedlings.
7. Research
Hypothesis
Ho: Jatropha curcas seedlings performance is
the same in sandy, sandy-loam, and clay-
loam textures
Ha: Jatropha curcas seedlings performance
is different in sandy, sandy-loam, and clay-
loam textures
8. Methodology
Site and conditions
Southeasth México
19° 16' 00" N and 96° 16' 32" W
18 m altitude
Natural conditions
Temperature: 19.8 ºC - 40.2 ºC
Humidity: 63.2%
9. Methodology
Biological material:
Non-toxic seeds
Location: 18º 59’52” N, 96º
15’ 31” W, 17 mosl
Physical data
Weight: 742.0 mg ± 24.3 mg
Length: 18.55 mm ± 0.68 mm
Width 10.3 mm ± 0.30 mm
Weight, Distribution: Normal
0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 1,1 1,2
0
20
40
60
80
100
120
140
160
180
No.ofobservations
11. Results
Soil analysis
Table 1. Soil chemical analysis and the method used for each test
Soil type pH Organic matter
(%)
Total N (%) P (ppm) Ca
(me/100g)
Mg
(me/100g)
Method Potentiometer Walkley-Black N=O.Mx0.05
Olsen-Kitson
Mellon Diehl et al. Diehl et al.
Sandy
7.81
(slightly alkaline)
Not detected
(very low)
Not detected
(very low)
2.8
(low) 3.859 7.717
Sandy-loam
7.26
(Neutral)
1.824
(medium)
0.0912
(low)
14.0
(medium) 8.770 14.733
Clay-loam
7.43
(slightly alkaline)
3.397
(high)
0.1698
(high)
34.0
(high) 16.487 25.958
12. Results
Soil effects on variables
Parameter
Substrates
Sandy Sandy-Loam Clay-Loam
Stem length (mm) 124 ± 19 c 226 ± 35 a 178 ± 23 b
Root collar diameter (mm) 9.9 ± 1.5 b 11.7 ± 1.7 a 10.8 ± 0.7 ab
Chlorophyll (SPAD) 23.4 ± 8.0 b 36.9 ± 12.0 a 29.3 ± 6.6 a
Number of true leafs 2.7 ± 1.4 b 7.3 ± 2.5 a 6.0 ± 3.3 a
Means within a column which do not share the same letter are significantly different (P < 0.05).
15. Results
Soil effects on variables
Number of leaves
Sandy Sandy-LoamClay-Loam
Number
0
2
4
6
8
Chlorophyll meter reading in leaves
Substract
Sandy Sandy-Loam Clay-Loam
SPADUnits
0
10
20
30
40
50
Sandy-Loam > Clay-Loam > Sandy
16. Results
Dry mass
a) Stem dry mass
Sandy Sandy-LoamClay-Loam
Weigth(g)
0,0
0,5
1,0
1,5
2,0
2,5
3,0
b) Root dry mass
Sandy Sandy-LoamClay-Loam
Rootsweigth(g)
0,0
0,2
0,4
0,6
0,8
1,0
1,2
1,4
1,6
c) Leaf dry mass
Sandy Sandy-LoamClay-Loam
Weigth(g)
0,0
0,5
1,0
1,5
2,0
2,5
3,0
Sandy-Loam > Clay-Loam > Sandy
17. Conclusions
Best growth on sandy-loam textures
Similar growth on clay-loam vs sandy-loam
Stem width, number of leaves, Chlorophyll, dry
mass
Chlorophyll level is higher in Sandy-loam
and clay-loam than in Sandy soils
Lowest growth on sandy textures
Clay-loam Sandy-loam Sandy
18. Conclusions
Null Hypothesis not accepted
J. curcas is sensitive to soil type
The nutritional contents are key for a good
development
Clay-loam Sandy-loam Sandy