GGE BIPLOT ANALYSIS OF YIELD STABI LITY FOR ANDEAN DRY BEAN ACCESSIONS GROWN UNDER DIFFERENT ABIOTIC STRESS REGIMES IN TANZANIA

Large seeded Andean dry beans (Phaseolus vulgaris L.) are most preferred in Africa. However, low soil fertility and increasing drought stress conditions due to climate change are among the challenges faced by farmers in this region. The purpose of this study was to identify Andean genotypes with yield stability and to identify the best environments for selection of this trait. GGE-Biplot analysis was used to examine 183 Andean bean genotypes in Tanzania. Results indicated significant environment (E), genotype (G) and genotype x environment (GE) effects for seed yield. The environment explained 46%, genotype 20%, and GE 34% of the total (G + E + GE) variation. Two principal components explained 41.21% (PC1) and 26.35% (PC2) of GGE sum of squares. The Andean genotypes, ADP-102 (Jessica)- purple mottle, large seed, bush plant habit, released by Selian Agriculture Research Institution (ARI) in Tanzania; ADP-220 (G5625)- red, large seed, vine plant habit, from Central America; ADP-276 (G13654) - brown, medium seed, vine, from Mexico; and ADP-648 (‘Red Kloud’) large red kidney, with bush plant habit, were stable across environments and can be recommended for general adaptation across environments. An individual location for selection for yield stability was not identified, thus justifying the continued need for multiple test sites

GGE BIPLOT ANALYSIS OF YIELD STABI LITY FOR ANDEAN DRY BEAN ACCESSIONS GROWN UNDER DIFFERENT ABIOTIC STRESS REGIMES IN TANZANIA

Large seeded Andean dry beans (Phaseolus vulgaris L.) are most preferred in Africa. However, low soil fertility and increasing drought stress conditions due to climate change are among the challenges faced by farmers in this region. The purpose of this study was to identify Andean genotypes with yield stability and to identify the best environments for selection of this trait. GGE-Biplot analysis was used to examine 183 Andean bean genotypes in Tanzania. Results indicated significant environment (E), genotype (G) and genotype x environment (GE) effects for seed yield. The environment explained 46%, genotype 20%, and GE 34% of the total (G + E + GE) variation. Two principal components explained 41.21% (PC1) and 26.35% (PC2) of GGE sum of squares. The Andean genotypes, ADP-102 (Jessica)- purple mottle, large seed, bush plant habit, released by Selian Agriculture Research Institution (ARI) in Tanzania; ADP-220 (G5625)- red, large seed, vine plant habit, from Central America; ADP-276 (G13654) - brown, medium seed, vine, from Mexico; and ADP-648 (‘Red Kloud’) large red kidney, with bush plant habit, were stable across environments and can be recommended for general adaptation across environments. An individual location for selection for yield stability was not identified, thus justifying the continued need for multiple test sites

The Potential of Local Landrace Varieties in Pearl Millet Improvement

SADCIICRISAT SMIP jointly naluated wth NARS rhr par1 millr! gennplasm from Tanzanta andZimbabwe in 1988189, andfrom Namibia in 1991/92 The obtectiva wre to tdentil.v. some su'o enor accessions that could be ra.~ td.iv t m. protied through gnd mars selertion or Itmired backcrossing and then release these back ro the fanning rmmuniryfor mitivation, and to select accessionr that could be tncorporatrd into he breeding program by crossing to create a dit~rntjed segregatingpopulation/rom which new improved vanntrs could be drveloprd Much heterosis tigor was observed in crossa betu~ern local landrace sanety (LLVJ arcessionr unth tmproved relellred vanetin Yteld supenonty of 6 8- 46 6% over the released vanety in Zimbabwe (PMV 2) w observed among intervaneta1 hybn& unth LLVs from Zimbabwe. Heterosts valuer as hlgh llr 98.9% over superior parents and a yteld superiority of up to 89 8Y) over the released tmriery tn Tanzunia (Serere 17) wen observed utirhin crosses tnvobiing 7hnzanian LLVs. In backcross studies to improve Okashanc I , progenies simdar to O k a s h a ~tn gnln sire and ttme to mtunry, but unih up to 24% supmoriry in yield and other tratt advantap, were tdrntified in the thtrd backcross ene era ti on. This study suggesrs that conrtderable potential exists for tmprovtng yirld and other traits prefrned by fanners through greater uttllration of LLVs tn bnrding progra

Evaluation of Crop Performance and Farmer Preference for Pearl Millet Varieties in Tanzania

This study was camed out to select an improved pearl millet variety acceptable to the farming community of Tanzania, after comparison with farmers' local kandrace varieties [LLVs). Twenty-one farmers from three districts participated. Improved varieties TSPM 91 01 8 and TSPM 91 001, which had been used in national on-station trials for more than three seasons and were found to be promising, were established in the farmers' fields in three districts in the 1993/94 season. The farmers' LLV and Serere 17, an improved released variety, were included in the Singida district trial for additional comparison

Seedling root architecture and its relationship with seed yield across diverse environments in \u3ci\u3ePhaseolus vulgaris\u3c/i\u3e

Seedling root phenotypes may have important impacts on fitness and are more easily measured than mature root phenotypes. We phenotyped the roots of 577 genotypes of common bean (Phaseolus vulgaris), representing the bulk of the genetic diversity for recent cultivars and landraces in this species. Root architectural phenotypes of seedlings germinated for nine days were compared to root architectural phenotypes in the field as well as seed yield across 51 environments with an array of abiotic stresses including drought, nutrient deficiency, and heat, as well as non-stress conditions. We observed repeatability ranging from 0.52–0.57 for measures of root phenotypes in seedlings, significant variation in root phene states between gene pools and races, relationships between seedling and field phenotypes, and varying correlations between seedling root phenes and seed yield under a variety of environmental conditions. Seed yield was significantly related to seedling basal root number in 22% of environments, seedling adventitious root abundance in 35% of environments, and seedling taproot length in 12% of environments. Cluster analysis grouped genotypes by their aggregated seedling root phenotype, and variation in seed yield among these clusters under non-stress, drought, and low fertility conditions was observed. These results highlight the existence and influence of integrated root phenotypes for adaptation to edaphic stress, and suggest root phenes have value as breeding targets under real-world conditions

Seedling root architecture and its relationship with seed yield across diverse environments in \u3ci\u3ePhaseolus vulgaris\u3c/i\u3e

Seedling root phenotypes may have important impacts on fitness and are more easily measured than mature root phenotypes. We phenotyped the roots of 577 genotypes of common bean (Phaseolus vulgaris), representing the bulk of the genetic diversity for recent cultivars and landraces in this species. Root architectural phenotypes of seedlings germinated for nine days were compared to root architectural phenotypes in the field as well as seed yield across 51 environments with an array of abiotic stresses including drought, nutrient deficiency, and heat, as well as non-stress conditions. We observed repeatability ranging from 0.52–0.57 for measures of root phenotypes in seedlings, significant variation in root phene states between gene pools and races, relationships between seedling and field phenotypes, and varying correlations between seedling root phenes and seed yield under a variety of environmental conditions. Seed yield was significantly related to seedling basal root number in 22% of environments, seedling adventitious root abundance in 35% of environments, and seedling taproot length in 12% of environments. Cluster analysis grouped genotypes by their aggregated seedling root phenotype, and variation in seed yield among these clusters under non-stress, drought, and low fertility conditions was observed. These results highlight the existence and influence of integrated root phenotypes for adaptation to edaphic stress, and suggest root phenes have value as breeding targets under real-world conditions

Seedling root architecture and its relationship with seed yield across diverse environments in \u3ci\u3ePhaseolus vulgaris\u3c/i\u3e

Seedling root phenotypes may have important impacts on fitness and are more easily measured than mature root phenotypes. We phenotyped the roots of 577 genotypes of common bean (Phaseolus vulgaris), representing the bulk of the genetic diversity for recent cultivars and landraces in this species. Root architectural phenotypes of seedlings germinated for nine days were compared to root architectural phenotypes in the field as well as seed yield across 51 environments with an array of abiotic stresses including drought, nutrient deficiency, and heat, as well as non-stress conditions. We observed repeatability ranging from 0.52–0.57 for measures of root phenotypes in seedlings, significant variation in root phene states between gene pools and races, relationships between seedling and field phenotypes, and varying correlations between seedling root phenes and seed yield under a variety of environmental conditions. Seed yield was significantly related to seedling basal root number in 22% of environments, seedling adventitious root abundance in 35% of environments, and seedling taproot length in 12% of environments. Cluster analysis grouped genotypes by their aggregated seedling root phenotype, and variation in seed yield among these clusters under non-stress, drought, and low fertility conditions was observed. These results highlight the existence and influence of integrated root phenotypes for adaptation to edaphic stress, and suggest root phenes have value as breeding targets under real-world conditions

Seedling root architecture and its relationship with seed yield across diverse environments in \u3ci\u3ePhaseolus vulgaris\u3c/i\u3e

Seedling root phenotypes may have important impacts on fitness and are more easily measured than mature root phenotypes. We phenotyped the roots of 577 genotypes of common bean (Phaseolus vulgaris), representing the bulk of the genetic diversity for recent cultivars and landraces in this species. Root architectural phenotypes of seedlings germinated for nine days were compared to root architectural phenotypes in the field as well as seed yield across 51 environments with an array of abiotic stresses including drought, nutrient deficiency, and heat, as well as non-stress conditions. We observed repeatability ranging from 0.52–0.57 for measures of root phenotypes in seedlings, significant variation in root phene states between gene pools and races, relationships between seedling and field phenotypes, and varying correlations between seedling root phenes and seed yield under a variety of environmental conditions. Seed yield was significantly related to seedling basal root number in 22% of environments, seedling adventitious root abundance in 35% of environments, and seedling taproot length in 12% of environments. Cluster analysis grouped genotypes by their aggregated seedling root phenotype, and variation in seed yield among these clusters under non-stress, drought, and low fertility conditions was observed. These results highlight the existence and influence of integrated root phenotypes for adaptation to edaphic stress, and suggest root phenes have value as breeding targets under real-world conditions

Seedling root architecture and its relationship with seed yield across diverse environments in \u3ci\u3ePhaseolus vulgaris\u3c/i\u3e

Seedling root phenotypes may have important impacts on fitness and are more easily measured than mature root phenotypes. We phenotyped the roots of 577 genotypes of common bean (Phaseolus vulgaris), representing the bulk of the genetic diversity for recent cultivars and landraces in this species. Root architectural phenotypes of seedlings germinated for nine days were compared to root architectural phenotypes in the field as well as seed yield across 51 environments with an array of abiotic stresses including drought, nutrient deficiency, and heat, as well as non-stress conditions. We observed repeatability ranging from 0.52–0.57 for measures of root phenotypes in seedlings, significant variation in root phene states between gene pools and races, relationships between seedling and field phenotypes, and varying correlations between seedling root phenes and seed yield under a variety of environmental conditions. Seed yield was significantly related to seedling basal root number in 22% of environments, seedling adventitious root abundance in 35% of environments, and seedling taproot length in 12% of environments. Cluster analysis grouped genotypes by their aggregated seedling root phenotype, and variation in seed yield among these clusters under non-stress, drought, and low fertility conditions was observed. These results highlight the existence and influence of integrated root phenotypes for adaptation to edaphic stress, and suggest root phenes have value as breeding targets under real-world conditions

Seedling root architecture and its relationship with seed yield across diverse environments in \u3ci\u3ePhaseolus vulgaris\u3c/i\u3e

Seedling root phenotypes may have important impacts on fitness and are more easily measured than mature root phenotypes. We phenotyped the roots of 577 genotypes of common bean (Phaseolus vulgaris), representing the bulk of the genetic diversity for recent cultivars and landraces in this species. Root architectural phenotypes of seedlings germinated for nine days were compared to root architectural phenotypes in the field as well as seed yield across 51 environments with an array of abiotic stresses including drought, nutrient deficiency, and heat, as well as non-stress conditions. We observed repeatability ranging from 0.52–0.57 for measures of root phenotypes in seedlings, significant variation in root phene states between gene pools and races, relationships between seedling and field phenotypes, and varying correlations between seedling root phenes and seed yield under a variety of environmental conditions. Seed yield was significantly related to seedling basal root number in 22% of environments, seedling adventitious root abundance in 35% of environments, and seedling taproot length in 12% of environments. Cluster analysis grouped genotypes by their aggregated seedling root phenotype, and variation in seed yield among these clusters under non-stress, drought, and low fertility conditions was observed. These results highlight the existence and influence of integrated root phenotypes for adaptation to edaphic stress, and suggest root phenes have value as breeding targets under real-world conditions