Improved technologies on yam for enhancing livelihood of farmers in Africa

Improved technologies on yam for enhancing
livelihood of farmers in Africa

-Progressed activities & further challenge-

Hidehiko KIKUNO (Yam physiologist)

International Institute of Tropical Agriculture
(IITA) Ibadan, Nigeria

14 October 2010
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org

Seed tubers

Seed yams required to plant one hectare

Stagnation of yam production could be mostly attributed to high production
costs.

Seed Tubers of Yam

• Expensive (as much as 63% of total variable cost)
• Bulky to transport
• Low multiplication rate in the field (1:5 – 1:10)
• Take time to release new varieties and breeding period
• Potential carriers of pests, pathogens and nematodes

Need for rapid methods for mass propagation
of high quality and healthy seed tubers


Capacity building
Development of meristem culture
protocol for yam germplasm
management

Communication

Improve propagation
Off-season yam
techniques
Other research
cropping system activities used
seedlings from
(Seed tuber from vine propagation
vine propagation) as new tool

Network Collaboration

Healthy seed tuber production
system on yam through vine
propagation

Development of meristem culture
protocol for yam germplasm
management

Communication Capacity building

Improve propagation
Off-season yam
techniques
Other research
cropping system activities used
seedlings from
(Seed tuber from vine propagation
vine propagation) as new tool

Network Collaboration

Healthy seed tuber production
system on yam through vine
propagation

Obstacle of meristem culture on yam

IITA has been maintaining germplasm collection
of yams (more than 3,000 accessions of
Dioscorea spp.) for distribution to NARIs

Meristem culture is an essential techniques
for virus free material and cryopreservation
for long term conservation

In vitro yam germplasm conservation
at IITA genebank

Low regeneration rate of shoots from meristem

Obstacle for clean germplasm collection and distribution


Materials and methods of meristem culture

Combination of plant growth regulators (NAA, BAP and GA3)
Basal media: MS, LS and B5 media

NAA (μM) BAP (μM) GA3 (μM)

0.05 0.20 0.00
0.05 0.20 0.30
0.05 0.60 0.00
0.05 0.60 0.30
0.10 0.20 0.00
0.10 0.20 0.30
0.10 0.60 0.00
0.10 0.60 0.30
0.50 0.20 0.00
0.50 0.20 0.30
0.50 0.60 0.00
0.50 0.60 0.30

10 meristems x 12 treatments = 120 x 3 media = 360 x 3 reps
= 1,080/accession (5meristem/petri-dish), 36 combinations


Procedure of meristem culture on yam

meristem

Plant materials Sterilization method
70% ethanol for 1 minute
（IITA Screen house） 1% sodium hypochlorite solution
for 15 minutes

TDr 95/18544 (White yam)
TDa 98/01183 (water yam)
Meristem on medium

Effect of plant growth regulator and media on shoot
regeneration (%) of (TDr 95/18544) 8 weeks after
meristem culture

Concentration of plant Medium
growth regulator (μM) MS LS B5*
NAA BAP GA3 N (%) N (%) N (%)
0.05 0.2 0.0 30 70.0 ab 29 55.9 abcd 21 85.7 a
0.3 27 55.2 abcd 29 58.9 abcd 21 76.0 a
0.6 0.0 30 73.3 a 30 26.7 e 21 76.0 a
0.3 30 73.3 a 30 63.3 abc 19 77.7 a
0.1 0.2 0.0 29 63.3 abc 30 66.7 ab 21 66.7 a
0.3 30 40.0 cde 30 51.8 abcd 21 90.7 a
0.6 0.0 30 73.3 a 25 33.3 de 21 71.7 a
0.3 25 66.7 ab 30 50.0 abcde 21 85.7 a
0.5 0.2 0.0 30 63.3 abc 25 66.7 ab 20 90.3 a
0.3 30 46.7 bcde 25 63.3 abcd 21 85.7 a
0.6 0.0 29 69.8 ab 30 53.3 abcd 21 62.0 a
0.3 29 58.1 abcd 30 40.0 cde 21 61.7 a
349 62.8 A 343 52.5 B 249 77.5

Different letters imply significant difference at 5% *B5 medium was separately
level tested

Effect of plant growth regulator and media on shoot
regeneration (%) of (TDa 98/01183) 8 weeks after
meristem culture

Concentration of plant Medium
growth regulator (μM) MS LS B5
NAA BAP GA3 N (%) N (%) N (%)
0.05 0.2 0.0 30 33.3 bc 30 40.0 b 30 80.0 a
0.3 29 18.0 bcdefg 29 23.7 bcde 30 30.0 bcd
0.6 0.0 30 20.0 bcdefg 30 23.3 bcdef 30 3.3 g
0.3 29 6.7 efg 30 13.3 cdefg 30 3.3 g
0.1 0.2 0.0 30 23.3 bcdef 29 32.0 bc 30 66.7 a
0.3 28 0.0 30 3.3 g 25 36.7 bc
0.6 0.0 25 3.3 efg 29 6.7 efg 30 0.0
0.3 28 3.3 fg 30 0.0 30 0.0
0.5 0.2 0.0 30 16.7 cdefg 30 10.0 defg 29 20.0 bcdefg
0.3 29 3.3 fg 30 0.0 29 34.0 bc
0.6 0.0 30 10.0 defg 30 6.7 efg 30 0.0
0.3 29 0.0 30 0.0 30 0.0
347 11.5 B 357 13.3 B 353 22.8 A
Different letters imply significant difference at 5% level


Effect of media component on callus formation(%)
of yam 8 weeks after planting

Accession Media
MS LS B5
TDr 95/18544 1.6A 4.7B 0.0
TDa 98/01183 10.8A 8.7A 0.8B

D. alata 8 weeks after planting
(MS+NAA 0.5μM,BAP 0.6μM)

Comparison of media component with PGRs between
IITA current media and best media with PGRs
combination for meristem culture

(The best component under this trials)
MS media + NAA 0.05μM + BAP 0.6μM

(Current media component used at Gene bank)
MS media + NAA 1.07μM+ BAP 0.67μM+ GA3 0.23μM

Effect of plant growth regulator and media on shoot regeneration
(%) of D. rotundata (TDr 95/18544 ) 8 weeks after planting
Concentration of plant growth
regulator (μM)
NAA BAP GA3 N (%)
0.05 0.6 0 37 92.0 a
1.07 0.67 0.23 39 54.0 b


Conclusion
1) Best media component with PGRs combination showed
higher rate of regeneration compared with current media
component to have been used at IITA Gene bank

2) Application of GA did not enhance regeneration of shoot and

3) B5 media showed less callus formation compared with MS
and LS

For stable conservation of germplasm of yam, it is best to use a
media which has less callus and high regenereation of shoot.

Although B5 media has a potential, further trials to test on more
species and accessions for making the protocol are needed.

Y. Hasegawa, H. Kikuno, B. Gueye, D. Dumet, O. Oyelami, H. Shiwachi and H. Takagi. (2010)
Preliminary screening of growth regulator and mineral combination to establish in vitro
meristem regeneration protocol for yam genebanking. Japanese Society for Tropical
Tropical Agriculture, Research for Tropical Agriculture Vol. 3, Extra issue 2, pp115-116.
October 09-10.

Healthy seed tuber
production system on yam
through vine propagation


Advantages of vine propagation of yams

1) High multiplication (more than 50 times)
(Depend on plants, variety, growth, and season)

2) Elimination of nematodes from tubers
(Clean land without nematodes is needed for culture)

3) To reduce usage of tubers which can use for foods or
seed tubers for next cropping season

4) To be able to produce mini-tubers with high sprouting
rate and uniformity of sprouting compared with those
of mini setts


Cond.

5) To be able to produce tubers (seed or ware) through
year round, leading off-season yam cropping

6) To be able to produce healthy seed tuber production
system (Availability of seedlings from tissue culture
materials propagated from meristem）

7) Rapid propagation of high yield improved varieties at
the beginning stage of dissemination to NARS or
farmers
8) Usage of research tools (i.e. screening materials,
rapid multiplication of breeding line or F1 plants)

Important technical points for
vine propagation studied

1)Healthy plant materials as mother plants of
vine cuttings
2) Type of planting materials
3) Physiological age of mother plants
4) New shoots formation from vine cutting
5) Timing of vine propagation (excising &
culture)

vine propagation

1)Healthy plant materials as mother plants of
vine cuttings
culture)

Production system for healthy plant materials as mother
plants of vine cuttings
In vitro plantlets Established plants in screen house

Seedlings acclimatized

Meristem culture Preparation of vine cuttings

Cond.


Effect of flowering & virus infection on the survival rate
Of vine cutting of white yam
Flowering Score of virus infection Flowering Mean of
Clone Survival % (No=0, (Nil=0,Low=3, Middle=6, survival
Yes=1) High=9) rate (%)
Amula 80.0ab 1 3 0 54.6A
TDr 95/19177 62.2bcde 0 3
TDr 95/18544 55.6cdef 0 3 1 44.4B
TDr 93-31 75.6abc 0 3
TDr 99/02789 37.8 1 6
TDr 96/00604 82.2a 0 0 Virus Inf. Mean of
TDr 97/00925 17.8 0 6 survival
TDr 96/01818 15.6 1 6 rate (%)
Meccakusa 48.9 0 3 0 82.2A
TDr 95/01932 64.4abcde 1 3
3 59.2B
TDr 89/02665 71.1abcd 0 3
TDr 98/01946 71.1abcd 0 6 9 33.7C
TDr 96/01750 15.6 1 3
TDr 01/00382 6.7 0 9
TDr 00/00365 53.3 1 9

Mean 50.5 0.4 4.4
Different letters indicate significant differences at the 1% level.

● Flower and virus infection effects on survival rate of vine propagation.


Type of planting materials


vine propagation

1)Use healthy plant materials as mother plants
of vine cuttings
culture)

Correlation between rooting of vine cutting and dry weight
of tuber formed on mother plants

100 (screen house) 50

Dry weight of tubers
80 40
Rooting (%)

Per plant (g)
60 30

40 20

20 10

0 0
60 90 120 150
Days after transplanting
100 300
(Field)

Dry weight of tubers
80 250

Per plant (g)
Rooting (%)

200
60
150
40 100
20 50
0
0
60 90 120 150
Days after transplanting
H. Kikuno, R. Matsumoto, H. Shiwachi, H. Toyohara and
Time course of rooting of vine cuttings and growth of R. Asiedu. (2007) Comparative effects of explants sources
tubers of mother plants on yams (D. alata cv. TDa and age of plant on rooting, shooting and tuber formation of
95/00361). Bars in each fig indicate % of vine cuttings vine cuttings from yams (Dioscorea spp.). Japanese Journal
of Tropical Agriculture Vol. 51, Extra issue 2, October 13-14.
with rooting.

60
a a

Shoot forma
50 b
40 a
a
30 b
20
b
10
b
0
1st 2nd 3rd 4th

100 Type A 100 Type B
Shoot formation rate (%)

90 a a
90
K-1 K-42 a *
80 80 K-44 Obuko.
70 a K-45 Arata 70 a
a
60 60
a a
50 b 50 b
40 a 40
a
30 b 30
b b
20 20
b
10 10
b b
0 0
1st 2nd 3rd 4th 1st 2nd 3rd 4th

100 Type B 100 Type C

90 90
* 80 K-31 K-32
80 a K-44 Obuko. Changes in shoot formation rate of vine
70
70 a
cuttings at different collection times.
60
60 50
Note) Different letters indicate significant
50 b 40
40 difference at the 5% level by LSD test.
30
30 ＊Obuko. stands for Obukosumbori
20
b b 10
20
0
10
b 1st 2nd 3rd 4th
0
Matsumoto R., H. Shiwachi, H. Kikuno, K. Irie, H. Toyohara, A. Komamine and H. Fujimaki. Characterization mother plantand shoot-forming
1st 2nd 3rd 4th Growth stage of of sprouting
processes of rooted cuttings of water yam (Dioscorea alata L.). Japanese Journal of Tropical Agriculture, Vol. 54 (3 or 4) (In press)
(%)

100 Type C International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org

Effect of collecting time of scions and, treatment of gibberellin and
Table 2 Effect of collecting time of scions and, treatment of gibberellin and uniconazol - P
on the growth of vine cuttings in water yam cuttings in water yam
uniconazol-P on the growth of vine
Rate of root fomation Rate of shoot formation Rate of mini tuber formation
Treatment 56 DAP
*
87 DAP 130 DAP 56 DAP 87 DAP 130 DAP 56 DAP 87 DAP 130 DAP
（ Jul.) （ Aug.）（ Oct.）
28 28 10 （ Jul.) （ Aug.）（ Oct.）
28 28 10 （ Jul.)
28 （ Aug.）（ Oct.）
28 10

control 90 a** 100 a 50 ab 100 a 65 b 0 0 35 b 100 a
10 mgl-1 30 c 50 b 50 ab 0 8c 0 100 a 92 a 100 a
GA
100 mgl-1 50 bc 60 ab 20 b 0 0 0 100 a 100 a 100 a
5 mgl-1 65 b 60 ab 65 a 44 b 83 ab 13 a 56 b 38 b 88 a
UZP
25 mgl-1 65 b 90 ab 30 ab 60 b 90 a 8a 40 b 10 b 92 a
* Day after planting (date of cutting)
** Different alphabets indicate significant difference at the 5% level by LSD test.

Matsumoto R., H. Shiwachi, H. Kikuno, K. Irie and H. Toyohara. Effect of collecting time of scions and treatment of gibberellin and uniconazole-P
on the growth of vine cuttings in water yam (Dioscorea alata L.). Japanese Journal of Tropical Agriculture Vol. 3 (2) or Vol. 4 (1) (2010) (In press).

R. Matsumoto, H. Shiwachi, H. Kikuno, K. Irie and H. Toyohara. (2010) Effect of collecting time of scions and, treatment of gibberellins and
uniconazol-P on the growth of vine cuttings in water yam (Dioscorea alata L.). Japanese Society for Tropical Agriculture, Research for Tropical
Agriculture Vol. 3, Extra issue 2, pp51-52. October 09-10, Okinawa, Japan.


Seedlings of vine cutting with new shoots


New shoots formation from vine
cutting

Table. Comparison of survival rate (%) of seedlings from vine cuttings of
yam (TDr 95/18544) at 60 days after transplanting at open-field under dry
season with irrigation.
Vine cuttings (VC) with Vine cuttings (VC) without
new shoots new shoots
No of planted
n = 120 n = 640
vine cuttings
No of survived
n = 102 n = 145
vine cuttings
% of survived
85.0 ± 5.0 22.7 ± 9.0
vine cuttings
Vine cuttings both planting materials (with and without new shoots) were
excised same day (10 October). Seedlings were cultured in screen house
for 1 month, then transplanted at open field by 25cm x 1m spacing. Data of
VC with new shoots and VC without new shoots were collected from 3 and
4 replications respectively.


Effects of seasons of vine cutting on the development of roots and tubers of yam
D.rotundata (TDr 89/2665) at 21days after vine cutting (DAC) each month.
Date of preparation of Number of % of vine cuttings % of vine cuttings
cuttings cuttings with new roots with new roots &
tubers

2009-05-26 n = 75 47 41
2009-06-25 n = 75 64 48
2009-07-30 n = 75 20 9
2009-08-30 n = 75 11 4

This results obtained from collaborative research with NARS partner
(NRCRI Umudike, Nigeria, Mazza Mary-Ann and Ikeorgu J. G.) in 2009

Yield of tubers through vine
propagation


200

180

160

140

120
Frequence

100

80

60

40

20

0
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Fresh w ei of tuber (g)
ght
Difference size of tubers harvested from plants which were propagated from vine cutting of
white yam (cv. TDr 95/ 18544) without rooting stage before planting into open field. Black and
white bars show frequency of tubers propagated from vine cuttings excised from plants
cultured in screen house which originated from tissue culture materials and from plants
cultured in open field propagated by mini sett of tuber. Plants were cultured from June 2008 to
December 2008 under natural weather condition.

How size of tuber can we harvest from seed tubers
propagated by vine cuttings？
Yield of tubers harvested from plants which were used different size of seed
tubers produced by vine propagation.
Size of seed tubers Fresh weight of tubers (g) / Estimated yield per ha
and mini-setts plant (Mt)

Less 10g (SHM) 427.6ab 17.2
Less 10g (FM) 325.6b 13.2
10-30g (SHM) 570.0a 22.8
10-30g (FM) 555.8a 22.4
25-30g sett
(Control) 391.6b 15.6
Mean 454.1±105.9 18.2±4.2
Seed tubers were planted by 25cm x 1m spacing on ridges. Seed tubers were
produced by vine propagation. Vine cuttings were directly planted in field
without rooting stage in July and seedlings established were cultured by
December for 6 months under natural rain condition. SHM: Plants (originated
from tissue culture materials) cultured in screen house, FM: Plants cultured
in open field (from mini-sett).


Harvested tubers from the plants
which seed tubers were propagated
by vine cuttings

From Mini-sett

*This trial has been repeated to use different clones in 2010.

Further direction for innovation to stabilize
vine propagation on yams

1) Stabilize shooting and rooting from vine cutting for all
type of plant materials (species and varieties)
2) To reduce technical steps for vine propagation (direct
planting of vine cutting)
3) Find alternative of carbonized rice husk (CRH) for
rooting media or reduce of quantity of CRH
4) Introduce virus detection test into this system
5) Expansion of usage of vine propagation for research
tools (i.e. breeding)


-Control of tuber dormancy-
Breakthrough of off-season (all year round)
yam cropping
Selection early or late sprouted tuber (traditional)

Broken dormancy
Plant growth regulators
(Gibberellic acids: GAs synthesis inhibitors)

Prolong dormancy
GA treatment
Low temperature storage (15℃)

Controlled cultivation through year round
Acclimatized plants from in vitro plantlets
Seedlings from vine propagation

Model of natural growth cycle of yam (cultivation) and
controlled growth cycle of yam for off-season cropping
Jan Jan
Dec Dorman- Feb
cy
Dec Sprout-
Maturing Dorman-
Planting Feb
-Harvest cy Sprout- Growth
Planting of top

Nov Mar Nov
Maturing Sprout- Dorman- Growth
-Harvest Planting cy of top
Mar

Oct Apr Oct i.e. VC
Tuber
Sprout- Dorman- Growth
enl.-
Planting cy of top
Apr
Harvest

Sep
Milking
Tuber Tuber
Growth Maturing
Sep enl.- May -Harvest
enlarge May
Harvest
of top Milking ment

Tuber
Tuber Maturing
Growth Aug -Harvest
enl.-
enlargem
ent
of top Jun Tuber Harvest Jun
Aug Growth enl.-
of top Harvest

Jul
Jul

Natural growth cycle of yam Controlled growth cycle of yam
★Clones from dormancy season shifted tubers will keep same life cycle. Control dormancy of tubers would be
Preferred by research institutes and it’s special seed tubers as like breeding variety disseminate to farmers.
Famers will just plant field in inland valleys, wet land or irrigated land under dry season.

• Strong price fluctuation of yam through year
• Yam price higher than other crops

Retail prices of major crops in Bida market
Millet
Yam 200
Rice
180
Sorghum
160
Cassava
140 Gari
Yam Tubers
Price (Naira/kg)

120

100

80

60

40

20

0
2004.01 2004.07 2005.01 2005.07 2006.01 2006.07 2007.01 2007.07 2008.01 2008.07
Year

Note: rainfall data is only available from 2005 to 2008.

Regina H. Y. Fu, H. Kikuno, M. Maruyama. Research on yam production, marketing and consumption of Nupe farmers of Bida region, Niger
State, central Nigeria. 47th Japan Association for African Studies, May 2010, Nara, Japan.

Off-season yam cropping

1) Enhance income of small householders to access in land valleys, wetland,
and irrigation land

2) Diversify crops to be adopted into wetland, irrigation land and inland
valleys with or without rice based cropping system

3) Supply foods in off crop season (especially beginning of rainy season)

Preliminary surveys to understand basic back ground of agricultural environments,
production of Bida, Niger state, Nigeria---JIRCAS collaborative research

Effects of nitrogen application on growth and yield under “Rice – Yam cropping
system”----JIRCAS collaborative research


Cultivated crops during dry season in inland valley
in Bida, Niger state Nigeria
Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug
Season Rain Rain Dry Dry Dry Dry Dry Dry Rain Rain Rain Rain
Dry Rain

Traditional R R R R C C C C C C C C
culitvation or or or or or or or or
V V V V V V V V

R = Rice, C = Cassava, V = Vegetables


Rice-Yam cropping system tested at inland valleys (3 villages)
in Bida, Niger state, Nigeria (support of WIN2000)

Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug
Season Rain Rain Dry Dry Dry Dry Dry Dry Rain Rain Rain Rain
Dry Rain

Traditional R R R R C C C C C C C C
culitvation or or or or or or or or
V V V V V V V V
Off-season R R R R R
yam cropping Y Y Y Y Y Y Y Y
(2009-2010) C C C C C C C C
F F F F F F F F
Off-season R R R R R
yam cropping
(2010-2011)

R = Rice (WITA4), C = Cassava, V = Vegetables, Y = Yam (TDr 95/18544), and F = Fallow


Rice-Yam cropping system tested at inland valleys (3 villages)
in Bida, Niger state, Nigeria (support of WIN2000)

Nov Jul
2009 2010

Jan Jul
2010 2010

Yield of yam & cassava in dry season cropping in inland valleys at Bida,
Niger state

Cassava Yam

Fresh weight of Water Fresh weight of tuber Water
Village Site
tuber (kg) /plant content (%) (kg)/plant content (%)
A 1.06 69.8 1.29 70.6
B 1.12 63.5 0.98 66.6
Lagun
C 1.77 62.4 1.22 69.1
Mean 1.32ac 65.2 1.16 a 68.8
A 0.24 68.4 0.76 65.8
B 0.76 61.8 1.26 67.2
Ejeti
C 0.77 57.8 0.83 71.5
Mean 0.59 b 62.6 0.95ab 68.2
A 1.04 64.3 0.66 70.6
B 1.68 56.4 0.82 71.8
Emitundata
C 0.47 64.8 0.94 70.8
Mean 1.06 c 61.8 0.80 b 71.0
Mean
0.99 63.2 0.97 69.3
(Total)
Different letters indicate significant differences at the 1% level.


Effects of nitrogen application on growth and yield of
yam under “Rice – Yam cropping system”

No of Fresh Weight of Water content in Dry Weight of
N treatment (t/ha)
tuber/plant tubers/plant （kg） tuber(%) top/plant (g)
Rice 0 -Yam 0 1.7 1.74 63.4 157.2
Rice 0 -Yam 60 2.0 2.62** 60.9** 224.8**
Rice 30 -Yam 0 1.4 1.43 63.1 136.1
Rice 30 -Yam 60 1.7 2.55** 59.1** 215.0**

Mean 1.7 2.08 61.7 183.3
** indicates significant differences at the 1% level.

Oct 2009 Jan 2010 July 2010


【Further
plan】
As those trials have been carrying out, all some
data will be collected by middle of 2011.

1)Identify the growth and yield of rice

2)Analysis of soil fertilities before rice, after yam
and after rice

3)Analysis of nutrients uptake from rice and yam


Optimum time for collection of root samples for
chromosome observation on yams
(Dioscorea spp.)

Obstacle of chromosome observation on yam

● Large number & very small size of chromosome (0.5μm～2.9μm)
● Acicular crystal in cell

● Difficult to collect picture of chromosomes in metaphase in cell which
is appropriate to chromosome observation.

Effective chromosome observation protocol for yam are needed.


Optimum time for collection of root samples for
chromosome observation

Roots from seedlings Roots from mini-sett
of vine cutting (dark condition)


1 2 3

1 Interphase
2 Prophase
3 Metaphase
4 Anaphase
5 Telophase

4 5

Periodicity in the cell division, TDr. 95/18544
(white yam)


【Results】
Roots from minisett

White yam Water yam

8 TDr. 95/18544 8 TDa. 98/01183
m ean no. of m etaphase cell
etaphase cell

m ean no.of m etaphase cels
l
7 LSD: 3.09 7 LSD: 3.56
6
a ab 6
5
ab 5 a a
4 4
3 b 3 a a a
2 b 2 a a
b b b a
1 1
0 0
1 4 7 10 13 16 19 22 1 4 7 10 13 16 19 22
ti e peri from sunrise (hours)
m od sunri (hours)
se ti e peri f
m od rom sunri (
se hours)

Chronometrical changes in the frequency of metaphase cells of root tips from minisett.
Different letters indicate significant differences at the 5% level. (Fisher’s LSD test)

● The peak in the frequency of metaphase cells is at 7 hr after sunrise (13:00pm)


【Results】
Roots from seedlings of vine cuttings

White yam Water yam

8 8
TDa. 98/01183

m ean no. of m etaphase cell
mean no. of metaphase cell

l
TDr. 95/18544

etaphase cel
a LSD: 3.13
7 7
LSD: 3.19
6 a 6
5 ab 5 ab ab
4 ab ab ab 4
b b
3 b 3 b
2 b b 2 b
1 1 b
0 0
1 4 7 10 13 16 19 22 1 4 7 10 13 16 19 22
time period from sunrise (hours)
timeperiod from sunrise (hours) ti e peri from sunrise
m od sunrise

Chronometrical changes in the frequency of metaphase cells of root tips from seedlings
of vine cutting. Different letters indicate significant differences at the 5% level. (Fisher’s
LSD test)
● The peak in the frequency of metaphase cells is at 4 hr after sunrise (10:00am)


【Conclusion】

Identified optimum time for collection of root
samples for chromosome observation through
year round due to usage of minisett (tuber-
under storage period) and seedlings of vine
cutting (growth stage)

Babil P.K., H. Kikuno, H. Shiwachi, H. Toyohara, J. Fujigaki,
H. Fujimaki, and R. Asiedu. Optimum time for collection of
root samples for chromosome observation in yams
(Dioscorea spp.). Tropical Agriculture and Development
Vol. 54 (3) (2010): pp.71-75.H.


Capacity building (Major research fellows)

Degree related students from African countries (more than 12 months)
1) 2007: Mr. Acha Ivo (Ph. D), Univ. Ibadan, Cameroon
2) 2009: Ms. Delphine Mapiemfu (Ph. D), (as adviser) Cameroon
3) 2010: Mr. Oyelami F. Olayemi (Msc), Univ. Ibadan, Nigeria
4) 2010: Ms. Okunade Adnike Oluwagade (Msc), Univ. Ibadan, Nigeria

Degree related students from Asian countries (6-7 months)
1) 2007: Mr. Babil Pachakkil Kalari Thotathil (Msc), Tokyo Univ. Agri. Japan, India
2) 2008: Mr. Kabindra Prasad Kandel (Msc), Tokyo Univ. Agri. Japan, Nepal
3) 2009: Mr. Yuichi Hasegawa (Msc), Tokyo Univ. Agri. Japan
4) 2010: Mr. Jyunya Ohata (Msc), Tokyo Univ. Agri. Japan

Japan-CGIAR Fellowship Program (2 months)
1) 2009: Mr. Takuya Koyama (Msc), Nagoya Univ., Japan
2) 2009: Ms. Saori Namba (Msc), Kobe Univ., Japan


On-the Job training (3-5 months)
Japan capacity building program for African
Agricultural Researchers funded by MAFF and
implemented by ICCAE, Nagoya Univ.

Rapid & mass propagation system for yams (Dioscorea spp.)
based on vine cuttings and tissue culture techniques

1) 2007: Mr. Shaali Mohamed Shaali, Kizimbani Research Station,
Zanzibar, (Tanzania)

2) 2007: Mr. Gerald Sereje, Root and Tuber Improvement Program, Mutanda
Research Station, Solwezi, Zambia

3) 2008: Mr. Yahaya Asieku, CSIR, Savanna Agric Research Institute (SARI),
Ghana

4) 2009: Mr. Ikoro Ikoro Anyim, NRCRI Umudike, Nigeria

5) 2009: Mr. Ouyabe Michel, CSRS/ESA (INP-HB), Cote d’Lvoire

6) 2010: Ms. Christine Kaari Gitonga, Kenya Agricultural Resaerch Institute,
National Genebank of Kenya, Kenya


Communication, Collaboration &
Network

Communication (Media)

2009: NHK-BS special and General, Japan, “Root and tuber
crops save the world” on air at 3 times
2009: NHK-BS, Japan, “World-Agora”
2010: Press tour 2010 hosted by the embassy of Japan
2007-2010: News papers, Magazines

Collaboration & Network

JIRCAS (2009-)
Tokyo University of Agriculture (2006-)
Kinki University (2006-)
Private sectors in Japan


Further challenges for enhancing
livelihood of farmers in Africa
through improved technologies on
yam

Packaging & distribution of clean seed production
system through improved propagation technologies

Development screening tools for agricultural traits
of yam using mini tubers or seedlings through vine
propagation

Other physiological & agronomic research activities

Expanding and strengthen research networks,
funding and collaboration

Packaging & distribution of clean seed
production system
through improved propagation

Activity 1:
Identification of robust technologies for propagation (vine
propagation, minisett techniques and in vitro micropropagation)
of high quality breeder’s and foundation seed to be adopted by
NARS in West Africa

Activity 2:
Backstopping study on vine propagation to be used by
commercial seed production farmers or intensive farmers with
potential to adopt mechanization

Activity 3:
Introduce clean & mass yam seed tuber production system
through vine propagation with/without in vitro micropropagation
for 5 NARS partners in West African countries.


Development diagnostic tools for agricultural traits
of yam using mini tubers or seedlings through vine
propagation

Activity 1:
Develop screening tools for resistance of nematodes using seedling
of vine cuttings

Activity 2:
Rapid & small-footprint method to identify and screen physiological
traits on yam (screening of maturity of plants, response of chemical
fertilizer, day length response, dormancy as well as drought
resistance) using seedlings or mini-tubers produced by vine
propagation


Thanks

*MOFA, Japan and embassy of Japan
*JIRCAS, Japan
*ICCAE, Nagoya University, Japan
*Tokyo University of Agriculture, Japan
*Kinki University (Hirose Project), Japan


Improved technologies on yam for enhancing livelihood of farmers in Africa

Empfohlen

Empfohlen

Weitere ähnliche Inhalte

Was ist angesagt?

Was ist angesagt? (20)

Ähnlich wie Improved technologies on yam for enhancing livelihood of farmers in Africa

Ähnlich wie Improved technologies on yam for enhancing livelihood of farmers in Africa (20)

Mehr von International Institute of Tropical Agriculture

Mehr von International Institute of Tropical Agriculture (20)

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

Improved technologies on yam for enhancing livelihood of farmers in Africa