Effect of Nitrogen Fixation on Yield and some Yield Component of Common Bean (Phaseolus vulgaris L.) Genotypes under Moisture Stress

Moisture stress is a worldwide production constraint for common beans and biological nitrogen fixation. The effect of drought has been widely reported and is an important environmental factor resulting in crop yield losses. This study aims at assessing the effect of nitrogen fixation on yield and some yield component of common bean (Phaseolus vulgaris L.) genotypes under moisture stress levels. Experiments were carried out in screen house and field at Sokoine University of Agriculture. The genotypes used were Kijivu, Yellow, Msolini, Masusu, Kasukanywele, Uyole 04, Mbulamtwe, Bilfa-Uyole and G 51495 A, a non-nodulating genotypes as a check. The soil moisture was maintained at 100, 75, 50 or 25% of the soil’s field capacity. Moisture stress reduced yield up to 67%. Genotypes Yellow (2.9 and 11.2g/palnt), Msolini (3.3 and 10.7g/plant), Masusu (3.6 and 7.7g/plant) and Bilfa Uyole (4.1 and 7.2g/plant) were observed to have some degree of drought tolerance based on its response under moisture stress environments for yield. These results suggest that moisture stress has a substantial impact on the general performance of common bean genotypes. Selection of superior performing genotypes under moisture stress, and integrating them into the breeding programs is an important to increase crop productivity. Keywords; N2-fixation; Drought; Nodulation; Legume

Description of Baetao-Manteiga 41 and ‘Yunguilla’ superior Andean common beans for Tanzanian production environments

An international effort was initiated with the evaluation of a diverse set of largeseeded Andean common beans (Phaseolus vulgaris L.), the Andean Diversity Panel, in sub-Saharan Africa. Several entries in the panel have been selected for extensive characterization on the basis of high performance acrossmultiple location × year trials in Tanzania—conducted both on station and on farm. Baetao- Manteiga 41, tested asADP-190, has a commercialKablanketi (light purple speckled) seed type, and ‘Yunguilla’, tested as ADP-447, has a commercial Calima (red mottled) seed type. Both lines exhibited yield stability, vigorous growth under low fertility conditions, angular leaf spot resistance, andmoderate common bacterial blight resistance; Yunguilla also possessed rust resistance. These two lines were tested, selected, and characterized cooperatively by Sokoine University of Agriculture (SUA), the Tanzanian Agricultural Research Institute (TARI), the USDA-ARS, and the Agricultural Research Council (ARC) of South Africa, and in collaboration with local farmers in Tanzania

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

Resistance of arcelin incorporated bean (Phaseolus vulgaris L.) hybrids and their parental cultivars against the bean bruchid Zabrotes subfasciatus (Boh)

Tanzania Journal of Agricultural Sciences 2001, Vol 4(1) : 23-28A hybridization bean breeding programme aimed at breeding beans resistant against the bean bruchid species Z. subfasciatus which destroys beans in storage was carried out at Sokoine University of Agriculture (SUA) Morogoro. Tanzania between 1994-1997. Five potential local bean varieties/lines were crossed to a bruchid resistant bean line RAZ 24-2 which was developed at SUA by selection from ClAT segregating RAZ bean populations. Seeds of RAZ lines contain arcelin a protein which confers resistance against Z. subfasciatus and can be transferred into other varietiess by hybridization. The backcross breeding procedure was adopted and five arcelin containing progenies were developed from this breeding programme. Seed of the developed progenies and those of the parents were then tested for resistance against Z. subfasciatus a randomized complete block design with 5 replications. There were significant difference, (P < 0. 05) in resistance against Z. subfasciatus among the genotypes. Results indicated that arcelin incorporated genotypes were superior over the arcelin deficient parents for resistance against Z. subfasciatus. Generally, the presence of arcelin in bean seeds delayed bruchid development reduced the number of emerged bruchids damage on bean seeds. However, bruchids managed to lay many eggs on seeds of all cultivars tested suggesting that bruchids are not inhibited from laying eggs on archelin containing seeds

Research note on the distribution and relative importance of bean bruchid species aconthoscelides obtectus (say.) and zabrotes subfosciatus (boh.) in Tanzania

Tanzania Journal of Agricultural Sciences 2000, VoL 3(2) : 181-184Two bean bruchid species Acanthoscelides·obtectus (Say.) and Zabrotes subfasciatus (Boh.) are known to destroy beans in storage. However, the distribution and relative. importance of these species have not been established in Tanzania. In this study, a bf!an bruchid survey was carried out to find out if the two bean bruchid species occurred in th~ country. The survey was corzduded In 1993 and it was observed that both bean bruchid species were present in all regions surveyed. However, the speCies A. obtectus was more dominant in all. regions except in Ruvuma and therefore' appeared to be relatively more important than Z. subfasciatus. The occurrence of the two species in all surveyed regions indicates that both species are of economic importance in the country. There was no indication that the two species occur in well defined ecological zones

Description of Baetao-Manteiga 41 and ‘Yunguilla’ superior Andean common beans for Tanzanian production environments

An international effort was initiated with the evaluation of a diverse set of largeseeded Andean common beans (Phaseolus vulgaris L.), the Andean Diversity Panel, in sub-Saharan Africa. Several entries in the panel have been selected for extensive characterization on the basis of high performance acrossmultiple location × year trials in Tanzania—conducted both on station and on farm. Baetao- Manteiga 41, tested asADP-190, has a commercialKablanketi (light purple speckled) seed type, and ‘Yunguilla’, tested as ADP-447, has a commercial Calima (red mottled) seed type. Both lines exhibited yield stability, vigorous growth under low fertility conditions, angular leaf spot resistance, andmoderate common bacterial blight resistance; Yunguilla also possessed rust resistance. These two lines were tested, selected, and characterized cooperatively by Sokoine University of Agriculture (SUA), the Tanzanian Agricultural Research Institute (TARI), the USDA-ARS, and the Agricultural Research Council (ARC) of South Africa, and in collaboration with local farmers in Tanzania