Feb 2017 Screening for drought tolerance in finger millet germplasm Henry Ojulong 1 , P Sheunda 1 , E Letayo 2 , L Nyaligwa 2 , J Kibuka 1 , D Otwani 1 and E Manyasa 1 Introduction • Drought is the most liming abioc stress in finger millet producon • Very lile has been done to explore resistance in the crop. • Finger millet is reported to have special mechanisms for drought resistance which some variees possess. • Drought tolerant lines will yield relavely 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 producve llers, 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 irrigaon was given at Kiboko and Miwaleni unl 50% flowering Results Kiboko • 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/ha Miwaleni • 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. 1 International Crops Research Institute for Semi-Arid Tropics (ICRISAT) Box 39063-00623, Nairobi-Kenya; 2 Department of Research and Development, Tanzania About ICRISAT: www.icrisat.org ICRISAT’s scienfic informaon: hp://EXPLOREit.icrisat.org Table 1. Means of agronomic traits of the best 10 yielders and a check across three locaons. Variety Seedling vigor Days to flowering Plant height Producve llers Lodged Plants Biomass (t/ha) Grain Yield (t/ha) 1000 Seed Weight IE 2187 2 59 65 6 3 2.82 2.02 2.30 IEFV 0090 2 66 72 3 0 3.27 1.50 2.03 IE 501 2 52 53 7 2 1.96 1.48 2.42 IE 593 2 54 58 4 3 2.00 1.45 2.47 IE 2030 2 56 53 7 3 2.51 1.43 2.35 IE 5791 1 61 68 3 3 2.52 1.37 1.93 IE 5165 2 61 65 2 1 2.99 1.37 2.15 IE 5812 1 62 66 3 1 2.56 1.35 2.40 IE 546 2 57 60 7 2 2.56 1.34 2.17 KNE 741 2 57 78 2 4 1.88 1.32 2.08 U 15 2 64 70 2 0 2.82 1.10 1.98 Mean 2 59 64 4 3 2.39 1.23 2.21 F pr. - <001 <001 <001 <001 <001 0.006 <001 l.s.d. - 2.75 6.00 1.04 0.80 0.80 1.20 0.37 cv% - 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 variaon Days to flowering Plant height Producve llers Lodged plants Biomass Seed weight Grain yield Rep 25.4 91.5 16.2*** 2.6 0.7* 0.7* 0.3 Genotype (G) 154*** 611.2*** 27.1*** 116*** 2.4*** 0.4** 0.6** Locaon (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 1.6 CV 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 loadings Traits PC 1 PC 2 PC 3 PC 4 PC 5 Seedling_vigor 0.292 0.385 0.550 -0.465 0.216 Agronomic score 0.446 -0.078 0.012 0.175 -0.479 Days to Flowering -0.459 0.180 0.073 -0.031 0.023 Plant Height -0.447 -0.163 -0.241 -0.005 -0.176 Producve llers 0.403 0.276 -0.162 0.476 -0.148 No of lodged plants 0.248 -0.494 -0.088 0.197 0.733 Biomass -0.250 0.494 0.187 0.626 0.287 1000 Seed weight 0.141 0.472 -0.752 -0.309 0.227 Eigen value 3.97 2.00 0.71 0.47 0.43 Percent total variance 49.68 24.96 8.91 5.87 5.38 Cumulave Variance 49.68 74.64 83.55 89.42 94.80 Principal component analysis • First three PCs explained most variaon (83.6%) (Table 3) • On PC1 variability contributed most by Agronomic score (0.446), producve llers (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 selecon 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 Locaon 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 producve llers, seed weight and grain yield • Locaon was the main source of variaon in all the traits Conclusion • Finger millet variees 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 irrigaon and sole natural precipitaon respecvely • Genotypes should be tested in their specific drought prone locaons due to the high locaon influence • Agronomic score, number of producve llers, 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 idenfied for potenal release and drought tolerant breeding populaon has been iniated Drought suscepble Drought resistant • Best for KYM: KNE 5791 & KNE 741 • Most stable genotypes across the locaons: IE 5791, KNE 741, IE 546, IE 6176, IE 5165, IE 5736, IE 5733 & IE 5635 • Best across locaons: IE 6013, IE 5635, IE 5845, IE 2957 Short growth duraon enables escapes of end of season (terminal) stress. Genotype ranking across locaons based on yield. HOPE