Feb 2017

Screening for drought tolerance in finger millet germplasmHenry Ojulong1, P Sheunda1, E Letayo2, L Nyaligwa2, J Kibuka1, D Otwani1 and E Manyasa1

Introduction• Drought is the most limiting abiotic stress in finger millet production• Very little has been done to explore resistance in the crop.• Finger millet is reported to have special mechanisms for drought resistance which

some varieties possess.• Drought tolerant lines will yield relatively well when water is scarce but do not lose

the ability to yield well in good seasons (Fleury et al. 2010)• A number of agronomic traits; seedling vigor, days to flowering (DAF), plant height,

number of productive tillers, amount of chaff (threshability) and grain yield have been used to assess drought tolerance in finger millet (Neshamba, 2010).

Material and Methods• 29 promising drought tolerant genotypes selected from the previous drought trials

and an improved drought tolerant check (U15) were tested in replicated trials at KALRO-Kiboko & KALRO-Kampi ya Mawe, Kenya and DRD-Miwaleni, Tanzania during the 2015 long rains and agronomic data taken.

• Supplementary irrigation was given at Kiboko and Miwaleni until 50% flowering

ResultsKiboko• Accessions with least DAF: IE 2957 (46), IE 3104 (48) & IE 501 (49). Check=68• Highest yielder: IE 6013 (2.0 t/ha), IE 593 (2.0 t/ha), IE 501 (2.1), IE 2187

(2.2 t/ha). Check =1.0 t/ha)Kampi ya Mawe• Accessions with least DAF: IE 2323 (57), IE 3104 (57), IE 5736 (59). Check=66 • Highest yielders: IE 5845 (0.5 t/ha), IE 5165 (0.5 t/ha), IE 546 (0.5 t/ha) & IEFV 0009

(1.0 t/ha). Check = 0.3 t/haMiwaleni• Accessions with least DAF: IE 501 (47), IE 2957 (47 & IE 593 (48)• Highest yielders KNE 741 (2.6 t/ha), IE 571 (2.8 t/ha) & IE 2187 (3.4 t/ha); Check

(2.0 t/ha)Combined analysis • Highest yielders: IE 595 (1.45 t/ha), IE 501 (1.48 t/ha), IEFV 0090, IE 2187 (2.02 t/ha).

Check= (1.1 t/ha) • Least DAF: IE 501 (52), IE 3104 (52), IE 2323 (53) & IE 2957 (53). Check (64)• Highest biomass IE 6013 (3.33 t/ha), IEFV 0090 (3.27 t/ha) & IE 5165 (2.99 t/ha)• Accessions U15, IEFV 0090 & IEFV 0094 were resistant to lodging.

1International Crops Research Institute for Semi-Arid Tropics (ICRISAT) Box 39063-00623, Nairobi-Kenya; 2 Department of Research and Development, Tanzania

About ICRISAT: www.icrisat.orgICRISAT’s scientific information: http://EXPLOREit.icrisat.org

Table 1. Means of agronomic traits of the best 10 yielders and a check across three locations.

VarietySeedling

vigorDays to

floweringPlant

heightProductive

tillersLodged Plants

Biomass (t/ha)

Grain Yield (t/ha)

1000 Seed

WeightIE 2187 2 59 65 6 3 2.82 2.02 2.30IEFV 0090 2 66 72 3 0 3.27 1.50 2.03IE 501 2 52 53 7 2 1.96 1.48 2.42IE 593 2 54 58 4 3 2.00 1.45 2.47IE 2030 2 56 53 7 3 2.51 1.43 2.35IE 5791 1 61 68 3 3 2.52 1.37 1.93IE 5165 2 61 65 2 1 2.99 1.37 2.15IE 5812 1 62 66 3 1 2.56 1.35 2.40IE 546 2 57 60 7 2 2.56 1.34 2.17KNE 741 2 57 78 2 4 1.88 1.32 2.08U 15 2 64 70 2 0 2.82 1.10 1.98Mean 2 59 64 4 3 2.39 1.23 2.21F pr. - <001 <001 <001 <001 <001 0.006 <001l.s.d. - 2.75 6.00 1.04 0.80 0.80 1.20 0.37cv% - 5.00 10.00 38.30 35.70 35.70 41.8 17.90

Table 2. ANOVA table for the different agronomic traits evaluated on 30 genotypes.Mean squares

Source of variation

Days to flowering Plant height

Productive tillers

Lodged plants Biomass

Seed weight

Grain yield

Rep 25.4 91.5 16.2*** 2.6 0.7* 0.7* 0.3Genotype (G) 154*** 611.2*** 27.1*** 116*** 2.4*** 0.4** 0.6**Location (L) 1361*** 8763*** 28.3*** 131*** 83.0*** 8.1*** 48.4***G x L 18.6*** 55.7 3.4* 12.6 0.8 0.3* 0.4*Residual 8.7 41.5 2.2 11.4 0.7 0.2 1.6CV 5.0 10.0 38.3 60.0 35.7 17.9 41.8

Table 3. Principle component coefficient of the various traits with principles of the various yield related traits.

Eigen loadingsTraits PC 1 PC 2 PC 3 PC 4 PC 5Seedling_vigor 0.292 0.385 0.550 -0.465 0.216Agronomic score 0.446 -0.078 0.012 0.175 -0.479Days to Flowering -0.459 0.180 0.073 -0.031 0.023Plant Height -0.447 -0.163 -0.241 -0.005 -0.176Productive tillers 0.403 0.276 -0.162 0.476 -0.148No of lodged plants 0.248 -0.494 -0.088 0.197 0.733Biomass -0.250 0.494 0.187 0.626 0.2871000 Seed weight 0.141 0.472 -0.752 -0.309 0.227Eigen value 3.97 2.00 0.71 0.47 0.43Percent total variance 49.68 24.96 8.91 5.87 5.38Cumulative Variance 49.68 74.64 83.55 89.42 94.80

Principal component analysis• First three PCs explained most variation

(83.6%) (Table 3)• On PC1 variability contributed most by

Agronomic score (0.446), productive tillers (0.403), days to flowering (-0.459) & plant height (-447)

• PC 2: Above ground biomass (0.494) and number of lodged plants (-0.447)

• PC 3: 1000 Seed weight (-0.752) & plant vigor (0.550)

Principal component analysis • Kiboko and KYM ideal for selection for

drought tolerance• Entries performed best at Kiboko and

least at Miwaleni• Best genotypes for Kiboko: IE6013,

IE501 & IE593• Best for KYM: IEFV 0009, IE 2323,

IE 5845 & IE 2957

ANOVA• Genotype and Location were

highly significant for all the traits assessed (table 2).

• G x L were highly significant (P<001) for days to flowering and significant (P=0.05) for number of productive tillers, seed weight and grain yield

• Location was the main source of variation in all the traits

Conclusion• Finger millet varieties have previously been selected purely for yield traits

and blast. However, ample variability exists within the germplasm to select for drought tolerance

• KALRO Kiboko and KALRO-Kampi ya Mawe are ideal sites for terminal drought screen under supplementary irrigation and sole natural precipitation respectively

• Genotypes should be tested in their specific drought prone locations due to the high location influence

• Agronomic score, number of productive tillers, maturity period, plant height, number of lodged plants above ground biomass and seed size are suitable as secondary traits for drought screening

• Drought tolerant accessions have been identified for potential release and drought tolerant breeding population has been initiatedDrought susceptible Drought resistant

• Best for KYM: KNE 5791 & KNE 741• Most stable genotypes across the locations: IE 5791, KNE 741, IE 546, IE 6176, IE

5165, IE 5736, IE 5733 & IE 5635• Best across locations: IE 6013, IE 5635, IE 5845, IE 2957

Short growth duration enables escapes of end of season (terminal) stress.

Genotype ranking across locations based on yield.

HOPE