Potential of Bambara Groundnut in Stabilizing Food Legume Production in Semi Arid Tropics of India The document discusses research on the potential of Bambara groundnut as an intercrop with groundnut to stabilize food legume production in semi-arid regions of India. It summarizes research that found genetic variability in water use efficiency (WUE) between Bambara groundnut accessions. Specifically, it found that the carbon isotope discrimination (Δ13C) technique can be used to rapidly screen accessions for higher WUE, and that crosses can be made to transfer desirable WUE traits into cultivated varieties. The research aims to improve Bambara groundnut through breeding strategies using traits and

1. Potential of Bambara Groundnut
(Vigna subterranea L.)
in Stabilizing Food Legume
Production in Semi Arid Tropics
of India
Dr. M S Basu
Formerly, Director ICAR &
Sub-Project Leader (India)
Funded by EU to University of Nottingham, UK

2. Background
1. In India, Oilseeds and
Pulses are grown in about
42 million hectare of
which Groundnut occupies
close to 7 m. ha.

3. 2. 80% of Groundnut area
is under rainfed and
average productivity is
around 1500 kg/ha.

4. 3. Productivity, however
fluctuates violently
depending upon vagaries
of monsoon:
(700-1800 kg/ha)

5. 4. To stabilize production in
dry lands, intercrops are
often introduced as
insurance crop.

6. 5. Groundnut based important
intercrops are:
Sesame, Castor and
Pigeonpea.

7. 6. Groundnut + Pigeonpea
system is most popular in
Gujarat and Andhra Pradesh
and grown in about 500,000
hectares but Pigeonpea
suffers due to its longer
duration.

8. 7. Groundnut + Bambara
therefore, could be a
suitable intercrop under
rainfed characterized by
low rainfall (400-600 mm)
& high temperature.

9. 8. Thus, National Research
Centre for Groundnut
(NRCG) ICAR introduced
Bambara Groundnut
Cultivars / Land races to
work on this crop.

10. Bambara Groundnut

11. 9. Research Initiated at NRCG on
Bambara Groundnut
(a) Basic studies on Specific
Leaf Area; Carbon Isotope
Discrimination;
Transpiration Efficiency and
Partitioning under
contrasting environments.

12. (b) Screening genotypes
tolerant to drought; high
temperature; soil salinity
and acid soils and use them
in crop improvement
programme.

13. Bambara Groundnut–Pink Podded

14. Bambara – Green Podded

15. (c) Inheritance of important
agronomic and physiological
traits and breeding for
developing varieties to suit
diverse agro-ecological
requirements.

16. 10. WUE and  13 C
WUE is a stable
physiological parameter with
high heritable trait useful for
crop improvement.

17. 11. There is strong causal
relationship between this
carbon isotope
discrimination (13C) and
WUE and therefore, it
provides scope to assess the
genetic variability for WUE.

18. 12. 13C technique is being
extensively used in
groundnut as a time
averaged surrogate to
estimate the genetic
variability in WUE.

19. 13. Experimental Materials and Sites
• Ten Bambara groundnut landraces
(SiG-5A, SB4-2, S19-3, Gabc, DODR, DODC,
DIPC, UNISWA Red, AS 17, AHM 753)
were grown in pots as well as under
field cond. at two different locations in
India
– Junagadh, (Western India)
– Hyderabad, A. P. (Southern India)

20. (a) Discrimination (13C) was
measured in dried leaf powder
(second leaf from top) using
Isotope Ratio Mass Spectrometer
(IRMS) at the Australian
National University (Canberra).
14. Methodology

21. (b) Specific Leaf Area (SLA) is the ratio
of leaf area to dry wt. (cm2. mg-1)
(c) Specific Leaf Nitrogen (SLN) is the
amount of nitrogen per unit leaf
area (mg N cm2) SLN = N% / SLA
* 100

22. 15. Results and Discussion
Flowering, fruiting and yield attributes
(a) The canopy development,
flowering, and maturity of
Bambara Groundnut
accessions introduced in India
were at par with Groundnut
genotypes.

23. (b) Days to flowering varies
with location:
SB 4-2 flowered earliest
(44 days) whereas DIPC
took 54 days to flower.

24. (c) DOD R from Tanzania had
the highest number of pods
(38/plants) followed by
AHM 753 and UNISWA
Red. The 100 seed mass
varied from 30.6 g (DOD C)
to 54.5 g (SIG-5A).

25. 16. Variability in 13C
(a) Significant differences in
13C observed, indicating
variability in WUE in
Bambara accessions.

26. (b) The 13C values of pot and
field grown plants showed
relationship indicating the
stability of this parameter.
y = 0.7737x + 4.2873
R2
= 0.6798
18.500
19.000
19.500
20.000
20.500
21.000
18.500 19.000 19.500 20.000 20.500 21.000
 13
C-field
Avg-D13C-pot
y = 0.69x + 5.9301
R2
= 0.4843
18.000
18.500
19.000
19.500
20.000
20.500
21.000
18.000 18.500 19.000 19.500 20.000 20.500 21.000
13
C-field (all reps)
13
C-pot(allreps)

27. (c) A significant inverse relationship between
N content and 13C suggest the
photosynthetic control of 13C and
WUE in Bambara groundnut accessions.
• Maintenance of a similar ranking
between field and pot plants indicate
lower G x E interaction for 13C and
hence WUE.
y = -2.7004x + 26.66
R2
= 0.5441
18.500
19.000
19.500
20.000
20.500
21.000
2.20 2.30 2.40 2.50 2.60 2.70 2.80 2.90
Avg-%N (pot)
Avg-13
C(pot)

28. 17. SLA showed an inverse relationship
with SLN indicating variability in
photosynthetic capacity of various
genotypes of Bambara groundnut.
y = -0.0089x + 3.275
R2
= 0.3719
1.50
1.60
1.70
1.80
1.90
2.00
2.10
2.20
2.30
2.40
2.50
90 100 110 120 130 140 150
Avg-SLA (pot)
Avg-SLN(pot)
y = - 1.3711x + 22.465
R 2
= 0.1594
18.500
19.000
19.500
20.000
20.500
21.000
1.75 1.85 1.95 2.05 2.15 2.25 2.35 2.45
Avg-SLN (pot)
Avg-3
C(pot)

29. 18. The 13C values in Bambara
groundnut were at par with
cultivated groundnut with high
WUE. The existing genetic
variability in WUE and 13C
suggests the possibility to
improve this species through
breeding strategies such as trait
based and marker aided.

30. 19. Further experiments are in
progress, which would
provide detailed insights
about the relationship of
these traits (SLN, SLA etc.)
with WUE.

31. Bambara Groundnut- Experiment

32. • As, 13C is a stable trait, it should be
used for rapid screening of Bambara
accessions for WUE and selection.
• Crosses can be effected to transfer
desirable traits into cultivated
background of Bambara and
segregating population can be
screened for superior biomass and
13C.
20. Conclusion

33. • The genotype that has superior
biomass coupled with low 13C
should perform better under any
given conditions of water
availability. In this direction, a
specific program has been initiated
at the NRCG in collaboration with
UAS, Bangalore.

34. • Also, the selected contrasting lines can
be crossed to develop mapping
populations (F2) of Bambara groundnut.
The most diverse cross combination can
be used for this purpose.
• Molecular assays by micro satellites or
any other suitable marker system can be
employed on these populations to
identify markers related to QTLs for the
traits of interest.

35. In Groundnut:
• Leaf N contributes to the capacity of
photosynthetic carbon fixation and WUE
and as photosynthetic capacity determines
WUE, SLN would be a better reflection of
WUE .
• The results suggest that SLN can be a good
indictor of mesophyll capacity in groundnut.
• The implications of SLA and SLN in
estimating WUE showed a strong inverse
relationship between SLA and SLN.