University of Aden Journal of Natural and Applied Sciences
Tomato is known to contain nutritional components with several types of health-promoting actions.... more Tomato is known to contain nutritional components with several types of health-promoting actions. Lycopene which is an antioxidant present in tomatoes has been identified as being responsible for the beneficial effect of tomatoes. With the aim of increasing the antioxidants contents of tomato, two dark fruited single recessive mutants were crossed to produce double mutant with higher antioxidants contents. The high pigment (hp) mutant of tomato characterized by dark green fruits, when it is immature and deep red mature fruit which is a monogenic mutant of tomato, was crossed with atroviolacea (atv) monogenic non-allelic mutant which had the same phenotype. Although it was easy to distinguish the hpatv segregating double mutant in the f2 generation, the conformation of the hpatv double mutant was made genetically. The double mutant showed darker phenotype in stem, leaves,and much darker fruits due to higher pigments content. The double mutant qualitatively showed higher pigments cont...
Assiut University Bulletin for Environmental Researches, 2010
Yemen is the richest country in the Arabian Peninsula in its biodiversity at all levels; genes, s... more Yemen is the richest country in the Arabian Peninsula in its biodiversity at all levels; genes, species, ecosystems and traditional knowledge. It is believed that the two serious threats to biodiversity are habitat destruction and nonnative species invasion in any ecosystem. Inspite of the observed threats of exotic invasive plant species in Yemen, these plants continue to be unchecked and unmonitored. The objective of this study is to provide information and accurate identification of the most abundant exotic invasive plant species. Pilot survey of these plant species was carried out mainly in mountainous areas which is the most fragile ecosystems. Interviews with local people for primary assessment of the invasive plant species impact were also made, in addition to primary field observations. The results indicated that new invasive plant species were recorded in the country, although they are very abundant at this time, Parthenium hysterophorus was recorded for the first time in hillsides in Hajah. Parthenium hysterophorus is sensitizer causes many health problems to human and animals, it also strong allelopathic weed. This weed in addition to the unpalatable and allelopathic Tagetes minuta has replaced native grazing vegetation in escarpment and the last has also invested the wastelands, roadsides, grazing lands, and abandoned fields even at above elevation of 3000 m. Tagetes minuta has led to reduction in population of Acacia asak trees and other species in the invasion areas. Opuntia dillenii was found at Bura mountains at the core of the protected area, its very serious threat to biodiversity and it causes blindness to animals and human whom get in contact with it. Other species were moving from the valleys upward in way to Bura mountains like Prosopis sp., on the other hand, new invasive spices of Nicotiania glauca was recorded in mountains surrounding Sana'a city. The distribution of some of the most abundant invasive plant species and their observed impact will be presented in this paper. Harbarium, National Agriculture and Water Research Center, Riyadh. Saudi Arabia. Chaudhary, S.A (2000): Flora of the Kingdom of Saudia Arabia. V. (2), Part3. Ministry of Agricultural and water, national Herbarium, National Agriculture and effects induced by the plants. J. Environ.
International Journal of Biology, Pharmacy and Allied Sciences, 2018
There is general agreement that biodiversity in Yemen is under threat due to mechanized rain-fed ... more There is general agreement that biodiversity in Yemen is under threat due to mechanized rain-fed agricultural expansion, urban expansion, wood logging and overgrazing. For all these reasons, this study finds it urgent to provide this ecological assessment for the plant diversity and vegetation conservation in Taiz. The floristic composition and habitat information were recorded in 150 sample sites. The description of the floristic composition and diversity patterns of the study area was achieved by using of a range of species richness and abundance methods as well as diversity indices. The study area of West Taiz contains about 252 species (about 168 species per hectare) belonging to 57 families, with 12 dominant species (5 %), 5 endemic species, 14 near endemic species and 17 rare species. The investigated areasare estimated 1.5 ha, which corresponds to 150 samples X 100 m² sample sites. The largest families in terms of species in the study sites arePoaceae (Graminea) with 25 species, Euphorbiaceaewith 20 species, Apocynaceae with18 species, Acanthaceae with18 species, Fabaceae (Papilionoideae) with 12 species andMimosaceae with 11 species. The occurrence of species in different landforms of the study area shows a characteristic pattern: the total richness of 186 for mountains, 171 for hills, 155 for wadis and 118 for plains.
Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. ... more Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. granatum L., were compared for the first time. Analysis of one P. protopunica and eleven P. granatum accessions was performed using three molecular markers, i.e., sequence related amplified polymorphism (SRAP), target region amplification polymorphism (TRAP), and intron targeted amplified polymorphism (ITAP), along with analysis of pgWD40 sequences, a gene involved in anthocyanin biosynthesis. All markers revealed the relationship between the two species and placed them at 33% similarity. SRAP, TRAP, and ITAP generated a total of 299, 260, and 160 bands, respectively. Of these, 78, 74, and 41 bands were specific for P. protopunica, and 92, 85, and 57 bands, respectively, were shared between both species. Sequence analysis of pgWD40*870 bp amplicons exhibited 100% identity among P. granatum accessions and 98% identity to that of P. protopunica. Phylogenetic analysis of WD40 sequences from monocot and dicot species, including both Punica species confirmed the relation between P. protopunica and P. granatum, supporting earlier reports that P. protopunica could be an ancestral species of P. granatum. Furthermore, the genetic diversity among and within P. granatum accessions from Egypt (3), Mexico (5), and Yemen (3) was assessed. Molecular marker-based relationships among region-bulked accessions was approximately the same (*90% similarity), whereas the degree of genetic variation was altered within each region. Specific bands (alleles) for accessions of each region along with those shared among them were identified. Thus, these bands could be used for pomegranate genotyping and breeding programs.
Developmental mutants serve as a useful material to unravel the mechanisms necessary for organ de... more Developmental mutants serve as a useful material to unravel the mechanisms necessary for organ development. The polycotyledon (poc) mutant of tomato, with multiple cotyledons in the seedling and varied phenotypic effects in the adult plant is one such mutant. Studies using physiological and anatomical methods in our lab suggest that POC is involved in the negative regulation of polar auxin transport, which is likely the reason for the pleiotropic phenotype in the mutant. Because of the physiological significance of the polycotyledon mutant described in this paper and also being first of its kind in tomato and also other plant species, we are using a map-based cloning approach to map the polycotyledon gene. Molecular mapping of this locus using segregating interspecific F2 mapping population localized polycotyledon gene close to TG424 marker on the long arm of chromosome 9. The closest marker mapped was a PCR marker identified in this study, E8A2 at a distance of 7.4 cM from the poc locus. The absence of tightly linked RAPD markers and the non-availability of more mapped markers in this region led us to initiate chromosome walk to polycotyledon gene. Both the flanking markers TG248 and E8A2 were used to screen the BAC library and a contig was developed for TG248 marker. The BAC-end sequences were analyzed for their use as RFLP markers to enrich this region for markers. Analysis of the BAC-end sequences revealed that poc is localized in the region surrounded by copia-like retrotransposon elements explaining the absence of markers in the euchromatin region on long arm of chromosome 9. Further studies identified two BAC-end sequences which mapped around the poc locus and also indicated very low physical versus genetic distance ratio in this region. The double mutant analyses of poc with the other two known polycotyledon mutants of tomato, pct and dem revealed allelism with pct; therefore, the poc mutant was named as pct1-2, and also the original pct mutant was renamed as pct1-1.
The polycotyledon mutant of tomato (Lycopersicon esculentum L. cv Ailsa Craig) showed altered dev... more The polycotyledon mutant of tomato (Lycopersicon esculentum L. cv Ailsa Craig) showed altered development during embryogenesis and during vegetative and reproductive phases. The phenotype was pleiotropic and included the formation of extra cotyledons, changes in leaf shape, increased number of flowers (indeterminacy) with abnormal floral organs, the formation of epiphyllous structures, and altered gravitropism. The earliest defects were observed at the transition from the globular to the heart stage of embryogenesis with the formation of multiple cotyledons. Epidermal cells in the mutant embryo were smaller and less expanded compared with wild type. Examination of polar auxin transport (PAT) showed a striking enhancement in the case of the mutant. Increase in PAT did not appear to be caused by a decrease in flavonoids because the mutant had normal flavonoid levels. Application of 2,3,5-triiodobenzoic acid, an inhibitor of polar transport of auxin, rescued postgermination phenotypes ...
Plant seeds used rely on a wide range of internal mechanisms and physio-chemical factors to ensur... more Plant seeds used rely on a wide range of internal mechanisms and physio-chemical factors to ensure their germination under favorable environmental conditions. Most plant seeds have complex process of germination, including water, oxygen, temperature availability, ...
Assiut University Bulletin for Environmental Researches
Allelopathic effect of water extracts of Tagetes minuta (Asteraceae) on seed germination and seed... more Allelopathic effect of water extracts of Tagetes minuta (Asteraceae) on seed germination and seedling growth of Acacia asak (Mimosaceae) was investigated. The root extracts showed no effect on seed germination percentages while leaf extracts has shown the highest germination inhibition effect. The seedling emergence in sand soil was strongly inhibited by leaf extracts; interestingly, this inhibition of emergence was reduced in sand clay soil. Leaf extracts also had shown the strongest radicle growth inhibition resulted in burning of the radicles' tips. It is concluded that allelochemical exerting the inhibition effect is most abundant in leaves and its effect is reduced with clay sand soil.
Allelopathic effect of water extracts of Tagetes minuta (Asteraceae) on seed germination and seed... more Allelopathic effect of water extracts of Tagetes minuta (Asteraceae) on seed germination and seedling growth of Acacia asak (Mimosaceae) was investigated. The root extracts showed no effect on seed germination percentages while leaf extracts has shown the highest germination inhibition effect. The seedling emergence in sand soil was strongly inhibited by leaf extracts; interestingly, this inhibition of emergence was reduced in sand clay soil. Leaf extracts also had shown the strongest radicle growth inhibition resulted in burning of the radicles' tips. It is concluded that allelochemical exerting the inhibition effect is most abundant in leaves and its effect is reduced with clay sand soil. INTRODUCTION:
The reliability of indirect method for ploidy level determination in two tomato varieties with th... more The reliability of indirect method for ploidy level determination in two tomato varieties with the same ploidy level was tested. Observations were made on traits used as indirect indictors of ploidy levels in plants on two varieties of diploid tomato which are characterized by significant differences in their size. The results revealed that all the morphological traits, pollen grain measurements as well as chloroplasts number in stomata guard cells significantly, differ in the two varieties although they are both diploid. In contrary, number of germinal pores in pollen grains and different stomata measurements, like stomata size, guard cell size and stomata frequency in addition to epidermal cell frequency, showed nonsignificant differences between the tested varieties. Thus, investigated traits, including stomata measurements and number of germinal pores, cannot be used to screen plants of Solanum Lycopersicum for ploidy level. Furthermore, the indirect method of ploidy level determination is species-specific and need to be confirmed by other methods.
University of Aden Journal of Natural & Applied Science, 2012
Invasive species are a major threat to environment mainly to biodiversity. Tagetes minuta (Astera... more Invasive species are a major threat to environment mainly to biodiversity. Tagetes minuta (Asteraceae) is an invasive plant in Yemen and has an aggressive and negative impact. The present work aims at to determining the germination behavior of invasive T. minuta and and noninvasive Tagetes erecta under different nutrient and salinity. Results showed a strong inhibition effect of salinity on the germination of both Tagetes species. In low salinity treatment (0.5 %), germination of invasive T.minuta was significantly lower than control (80% vs. 100%) while no germination sings observed in medium (1%) and high salinity treatments (2%). In medium and high salinity treatments (1 % and 2%), achenes of invasive T. minuta germination reached 96.94% and 100% as recovery percentage, indicating an osmotic inhibitory effect. In contrast, the recovery percentages exhibited by non invasive T. erecta reached only 47.75% and 15% which is ascribed to toxic effect as well as low achenes viability. The high viability of invasive T.minuta achenes, in addition to its salt tolerance, are two attributes related to its invasiveness.
There is general agreement that biodiversity in Yemen is under threat due to mechanized rain-fed ... more There is general agreement that biodiversity in Yemen is under threat due to mechanized rain-fed agricultural expansion, urban expansion, wood logging and overgrazing. For all these reasons, this study finds it urgent to provide this ecological assessment for the plant diversity and vegetation conservation in . The floristic composition and habitat information were recorded in 150 sample sites. The description of the floristic composition and diversity patterns of the study area was achieved by using of a range of species richness and abundance methods as well as diversity indices. The study area of West Taiz contains about 252 species (about 168 species per hectare) belonging to 57 families, with 12 dominant species (5 %), 5 endemic species, 14 near endemic species and 17 rare species. The investigated areasare estimated 1.5 ha, which corresponds to 150 samples X 100 m² sample sites. The largest families in terms of species in the study sites arePoaceae (Graminea) with 25 species, Euphorbiaceaewith 20 species, Apocynaceae with18 species, Acanthaceae with18 species, Fabaceae (Papilionoideae) with 12 species andMimosaceae with 11 species. The occurrence of species in different landforms of the study area shows a characteristic pattern: the total richness of 186 for mountains, 171 for hills, 155 for wadis and 118 for plains.
Developmental mutants serve as a useful material to unravel the mechanisms necessary for organ de... more Developmental mutants serve as a useful material to unravel the mechanisms necessary for organ development. The polycotyledon (poc) mutant of tomato, with multiple cotyledons in the seedling and varied phenotypic eVects in the adult plant is one such mutant. Studies using physiological and anatomical methods in our lab suggest that POC is involved in the negative regulation of polar auxin transport, which is likely the reason for the pleiotropic phenotype in the mutant. Because of the physiological signiWcance of the polycotyledon mutant described in this paper and also being Wrst of its kind in tomato and also other plant species, we are using a map-based cloning approach to map the polycotyledon gene. Molecular mapping of this locus using segregating interspeciWc F 2 mapping population localized polycotyledon gene close to TG424 marker on the long arm of chromosome 9. The closest marker mapped was a PCR marker identiWed in this study, E8A2 at a distance of 7.4 cM from the poc locus. The absence of tightly linked RAPD markers and the non-availability of more mapped markers in this region led us to initiate chromosome walk to poly-cotyledon gene. Both the Xanking markers TG248 and E8A2 were used to screen the BAC library and a con-tig was developed for TG248 marker. The BAC-end sequences were analyzed for their use as RFLP markers to enrich this region for markers. Analysis of the BAC-end sequences revealed that poc is localized in the region surrounded by copia-like retrotransposon elements explaining the absence of markers in the euchromatin region on long arm of chromosome 9. Further studies identiWed two BAC-end sequences which mapped around the poc locus and also indicated very low physical versus genetic distance ratio in this region. The double mutant analyses of poc with the other two known polycotyledon mutants of tomato, pct and dem revealed allelism with pct; therefore, the poc mutant was named as pct1-2, and also the original pct mutant was renamed as pct1-1.
Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. ... more Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. granatum L., were compared for the first time. Analysis of one P. protopunica and eleven P. grana-tum accessions was performed using three molecular markers, i.e., sequence related amplified polymor-phism (SRAP), target region amplification polymor-phism (TRAP), and intron targeted amplified polymorphism (ITAP), along with analysis of pgWD40 sequences, a gene involved in anthocyanin biosynthesis. All markers revealed the relationship between the two species and placed them at 33% similarity. SRAP, TRAP, and ITAP generated a total of 299, 260, and 160 bands, respectively. Of these, 78, 74, and 41 bands were specific for P. protopunica, and 92, 85, and 57 bands, respectively, were shared between both species. Sequence analysis of pgWD40*870 bp amplicons exhibited 100% identity among P. granatum accessions and 98% identity to that of P. protopunica. Phylogenetic analysis of WD40 sequences from monocot and dicot species, including both Punica species confirmed the relation between P. protopunica and P. granatum, supporting earlier reports that P. protopunica could be an ancestral species of P. granatum. Furthermore, the genetic diversity among and within P. granatum accessions from Egypt (3), Mexico (5), and Yemen (3) was assessed. Molecular marker-based relationships among region-bulked accessions was approximately the same (*90% similarity), whereas the degree of genetic variation was altered within each region. Specific bands (alleles) for accessions of each region along with those shared among them were identified. Thus, these bands could be used for pomegranate genotyping and breeding programs.
Yemen is the richest country in the Arabian Peninsula in its biodiversity at all levels; genes, s... more Yemen is the richest country in the Arabian Peninsula in its biodiversity at all levels; genes, species, ecosystems and traditional knowledge. It is believed that the two serious threats to biodiversity are habitat destruction and nonnative species invasion in any ecosystem. Inspite of the observed threats of exotic invasive plant species in Yemen, these plants continue to be unchecked and unmonitored. The objective of this study is to provide information and accurate identification of the most abundant exotic invasive plant species. Pilot survey of these plant species was carried out mainly in mountainous areas which is the most fragile ecosystems. Interviews with local people for primary assessment of the invasive plant species impact were also made, in addition to primary field observations. The results indicated that new invasive plant species were recorded in the country, although they are very abundant at this time, Parthenium hysterophorus was recorded for the first time in hillsides in Hajah. Parthenium hysterophorus is sensitizer causes many health problems to human and animals, it also strong allelopathic weed. This weed in addition to the unpalatable and allelopathic Tagetes minuta has replaced native grazing vegetation in escarpment and the last has also invested the wastelands, roadsides, grazing lands, and abandoned fields even at above elevation of 3000 m. Tagetes minuta has led to reduction in population of Acacia asak trees and other species in the invasion areas. Opuntia dillenii was found at Bura mountains at the core of the protected area, its very serious threat to biodiversity and it causes blindness to animals and human whom get in contact with it.
The polycotyledon mutant of tomato (Lycopersicon esculentum L. cv Ailsa Craig) showed altered dev... more The polycotyledon mutant of tomato (Lycopersicon esculentum L. cv Ailsa Craig) showed altered development during embryogenesis and during vegetative and reproductive phases. The phenotype was pleiotropic and included the formation of extra cotyledons, changes in leaf shape, increased number of flowers (indeterminacy) with abnormal floral organs, the formation of epiphyllous structures, and altered gravitropism. The earliest defects were observed at the transition from the globular to the heart stage of embryogenesis with the formation of multiple cotyledons. Epidermal cells in the mutant embryo were smaller and less expanded compared with wild type. Examination of polar auxin transport (PAT) showed a striking enhancement in the case of the mutant. Increase in PAT did not appear to be caused by a decrease in flavonoids because the mutant had normal flavonoid levels. Application of 2,3,5-triiodobenzoic acid, an inhibitor of polar transport of auxin, rescued postgermination phenotypes of young seedlings. Our analysis reveals a level of control that negatively regulates PAT in tomato and its contribution to plant development and organogenesis.
University of Aden Journal of Natural and Applied Sciences
Tomato is known to contain nutritional components with several types of health-promoting actions.... more Tomato is known to contain nutritional components with several types of health-promoting actions. Lycopene which is an antioxidant present in tomatoes has been identified as being responsible for the beneficial effect of tomatoes. With the aim of increasing the antioxidants contents of tomato, two dark fruited single recessive mutants were crossed to produce double mutant with higher antioxidants contents. The high pigment (hp) mutant of tomato characterized by dark green fruits, when it is immature and deep red mature fruit which is a monogenic mutant of tomato, was crossed with atroviolacea (atv) monogenic non-allelic mutant which had the same phenotype. Although it was easy to distinguish the hpatv segregating double mutant in the f2 generation, the conformation of the hpatv double mutant was made genetically. The double mutant showed darker phenotype in stem, leaves,and much darker fruits due to higher pigments content. The double mutant qualitatively showed higher pigments cont...
Assiut University Bulletin for Environmental Researches, 2010
Yemen is the richest country in the Arabian Peninsula in its biodiversity at all levels; genes, s... more Yemen is the richest country in the Arabian Peninsula in its biodiversity at all levels; genes, species, ecosystems and traditional knowledge. It is believed that the two serious threats to biodiversity are habitat destruction and nonnative species invasion in any ecosystem. Inspite of the observed threats of exotic invasive plant species in Yemen, these plants continue to be unchecked and unmonitored. The objective of this study is to provide information and accurate identification of the most abundant exotic invasive plant species. Pilot survey of these plant species was carried out mainly in mountainous areas which is the most fragile ecosystems. Interviews with local people for primary assessment of the invasive plant species impact were also made, in addition to primary field observations. The results indicated that new invasive plant species were recorded in the country, although they are very abundant at this time, Parthenium hysterophorus was recorded for the first time in hillsides in Hajah. Parthenium hysterophorus is sensitizer causes many health problems to human and animals, it also strong allelopathic weed. This weed in addition to the unpalatable and allelopathic Tagetes minuta has replaced native grazing vegetation in escarpment and the last has also invested the wastelands, roadsides, grazing lands, and abandoned fields even at above elevation of 3000 m. Tagetes minuta has led to reduction in population of Acacia asak trees and other species in the invasion areas. Opuntia dillenii was found at Bura mountains at the core of the protected area, its very serious threat to biodiversity and it causes blindness to animals and human whom get in contact with it. Other species were moving from the valleys upward in way to Bura mountains like Prosopis sp., on the other hand, new invasive spices of Nicotiania glauca was recorded in mountains surrounding Sana'a city. The distribution of some of the most abundant invasive plant species and their observed impact will be presented in this paper. Harbarium, National Agriculture and Water Research Center, Riyadh. Saudi Arabia. Chaudhary, S.A (2000): Flora of the Kingdom of Saudia Arabia. V. (2), Part3. Ministry of Agricultural and water, national Herbarium, National Agriculture and effects induced by the plants. J. Environ.
International Journal of Biology, Pharmacy and Allied Sciences, 2018
There is general agreement that biodiversity in Yemen is under threat due to mechanized rain-fed ... more There is general agreement that biodiversity in Yemen is under threat due to mechanized rain-fed agricultural expansion, urban expansion, wood logging and overgrazing. For all these reasons, this study finds it urgent to provide this ecological assessment for the plant diversity and vegetation conservation in Taiz. The floristic composition and habitat information were recorded in 150 sample sites. The description of the floristic composition and diversity patterns of the study area was achieved by using of a range of species richness and abundance methods as well as diversity indices. The study area of West Taiz contains about 252 species (about 168 species per hectare) belonging to 57 families, with 12 dominant species (5 %), 5 endemic species, 14 near endemic species and 17 rare species. The investigated areasare estimated 1.5 ha, which corresponds to 150 samples X 100 m² sample sites. The largest families in terms of species in the study sites arePoaceae (Graminea) with 25 species, Euphorbiaceaewith 20 species, Apocynaceae with18 species, Acanthaceae with18 species, Fabaceae (Papilionoideae) with 12 species andMimosaceae with 11 species. The occurrence of species in different landforms of the study area shows a characteristic pattern: the total richness of 186 for mountains, 171 for hills, 155 for wadis and 118 for plains.
Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. ... more Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. granatum L., were compared for the first time. Analysis of one P. protopunica and eleven P. granatum accessions was performed using three molecular markers, i.e., sequence related amplified polymorphism (SRAP), target region amplification polymorphism (TRAP), and intron targeted amplified polymorphism (ITAP), along with analysis of pgWD40 sequences, a gene involved in anthocyanin biosynthesis. All markers revealed the relationship between the two species and placed them at 33% similarity. SRAP, TRAP, and ITAP generated a total of 299, 260, and 160 bands, respectively. Of these, 78, 74, and 41 bands were specific for P. protopunica, and 92, 85, and 57 bands, respectively, were shared between both species. Sequence analysis of pgWD40*870 bp amplicons exhibited 100% identity among P. granatum accessions and 98% identity to that of P. protopunica. Phylogenetic analysis of WD40 sequences from monocot and dicot species, including both Punica species confirmed the relation between P. protopunica and P. granatum, supporting earlier reports that P. protopunica could be an ancestral species of P. granatum. Furthermore, the genetic diversity among and within P. granatum accessions from Egypt (3), Mexico (5), and Yemen (3) was assessed. Molecular marker-based relationships among region-bulked accessions was approximately the same (*90% similarity), whereas the degree of genetic variation was altered within each region. Specific bands (alleles) for accessions of each region along with those shared among them were identified. Thus, these bands could be used for pomegranate genotyping and breeding programs.
Developmental mutants serve as a useful material to unravel the mechanisms necessary for organ de... more Developmental mutants serve as a useful material to unravel the mechanisms necessary for organ development. The polycotyledon (poc) mutant of tomato, with multiple cotyledons in the seedling and varied phenotypic effects in the adult plant is one such mutant. Studies using physiological and anatomical methods in our lab suggest that POC is involved in the negative regulation of polar auxin transport, which is likely the reason for the pleiotropic phenotype in the mutant. Because of the physiological significance of the polycotyledon mutant described in this paper and also being first of its kind in tomato and also other plant species, we are using a map-based cloning approach to map the polycotyledon gene. Molecular mapping of this locus using segregating interspecific F2 mapping population localized polycotyledon gene close to TG424 marker on the long arm of chromosome 9. The closest marker mapped was a PCR marker identified in this study, E8A2 at a distance of 7.4 cM from the poc locus. The absence of tightly linked RAPD markers and the non-availability of more mapped markers in this region led us to initiate chromosome walk to polycotyledon gene. Both the flanking markers TG248 and E8A2 were used to screen the BAC library and a contig was developed for TG248 marker. The BAC-end sequences were analyzed for their use as RFLP markers to enrich this region for markers. Analysis of the BAC-end sequences revealed that poc is localized in the region surrounded by copia-like retrotransposon elements explaining the absence of markers in the euchromatin region on long arm of chromosome 9. Further studies identified two BAC-end sequences which mapped around the poc locus and also indicated very low physical versus genetic distance ratio in this region. The double mutant analyses of poc with the other two known polycotyledon mutants of tomato, pct and dem revealed allelism with pct; therefore, the poc mutant was named as pct1-2, and also the original pct mutant was renamed as pct1-1.
The polycotyledon mutant of tomato (Lycopersicon esculentum L. cv Ailsa Craig) showed altered dev... more The polycotyledon mutant of tomato (Lycopersicon esculentum L. cv Ailsa Craig) showed altered development during embryogenesis and during vegetative and reproductive phases. The phenotype was pleiotropic and included the formation of extra cotyledons, changes in leaf shape, increased number of flowers (indeterminacy) with abnormal floral organs, the formation of epiphyllous structures, and altered gravitropism. The earliest defects were observed at the transition from the globular to the heart stage of embryogenesis with the formation of multiple cotyledons. Epidermal cells in the mutant embryo were smaller and less expanded compared with wild type. Examination of polar auxin transport (PAT) showed a striking enhancement in the case of the mutant. Increase in PAT did not appear to be caused by a decrease in flavonoids because the mutant had normal flavonoid levels. Application of 2,3,5-triiodobenzoic acid, an inhibitor of polar transport of auxin, rescued postgermination phenotypes ...
Plant seeds used rely on a wide range of internal mechanisms and physio-chemical factors to ensur... more Plant seeds used rely on a wide range of internal mechanisms and physio-chemical factors to ensure their germination under favorable environmental conditions. Most plant seeds have complex process of germination, including water, oxygen, temperature availability, ...
Assiut University Bulletin for Environmental Researches
Allelopathic effect of water extracts of Tagetes minuta (Asteraceae) on seed germination and seed... more Allelopathic effect of water extracts of Tagetes minuta (Asteraceae) on seed germination and seedling growth of Acacia asak (Mimosaceae) was investigated. The root extracts showed no effect on seed germination percentages while leaf extracts has shown the highest germination inhibition effect. The seedling emergence in sand soil was strongly inhibited by leaf extracts; interestingly, this inhibition of emergence was reduced in sand clay soil. Leaf extracts also had shown the strongest radicle growth inhibition resulted in burning of the radicles' tips. It is concluded that allelochemical exerting the inhibition effect is most abundant in leaves and its effect is reduced with clay sand soil.
Allelopathic effect of water extracts of Tagetes minuta (Asteraceae) on seed germination and seed... more Allelopathic effect of water extracts of Tagetes minuta (Asteraceae) on seed germination and seedling growth of Acacia asak (Mimosaceae) was investigated. The root extracts showed no effect on seed germination percentages while leaf extracts has shown the highest germination inhibition effect. The seedling emergence in sand soil was strongly inhibited by leaf extracts; interestingly, this inhibition of emergence was reduced in sand clay soil. Leaf extracts also had shown the strongest radicle growth inhibition resulted in burning of the radicles' tips. It is concluded that allelochemical exerting the inhibition effect is most abundant in leaves and its effect is reduced with clay sand soil. INTRODUCTION:
The reliability of indirect method for ploidy level determination in two tomato varieties with th... more The reliability of indirect method for ploidy level determination in two tomato varieties with the same ploidy level was tested. Observations were made on traits used as indirect indictors of ploidy levels in plants on two varieties of diploid tomato which are characterized by significant differences in their size. The results revealed that all the morphological traits, pollen grain measurements as well as chloroplasts number in stomata guard cells significantly, differ in the two varieties although they are both diploid. In contrary, number of germinal pores in pollen grains and different stomata measurements, like stomata size, guard cell size and stomata frequency in addition to epidermal cell frequency, showed nonsignificant differences between the tested varieties. Thus, investigated traits, including stomata measurements and number of germinal pores, cannot be used to screen plants of Solanum Lycopersicum for ploidy level. Furthermore, the indirect method of ploidy level determination is species-specific and need to be confirmed by other methods.
University of Aden Journal of Natural & Applied Science, 2012
Invasive species are a major threat to environment mainly to biodiversity. Tagetes minuta (Astera... more Invasive species are a major threat to environment mainly to biodiversity. Tagetes minuta (Asteraceae) is an invasive plant in Yemen and has an aggressive and negative impact. The present work aims at to determining the germination behavior of invasive T. minuta and and noninvasive Tagetes erecta under different nutrient and salinity. Results showed a strong inhibition effect of salinity on the germination of both Tagetes species. In low salinity treatment (0.5 %), germination of invasive T.minuta was significantly lower than control (80% vs. 100%) while no germination sings observed in medium (1%) and high salinity treatments (2%). In medium and high salinity treatments (1 % and 2%), achenes of invasive T. minuta germination reached 96.94% and 100% as recovery percentage, indicating an osmotic inhibitory effect. In contrast, the recovery percentages exhibited by non invasive T. erecta reached only 47.75% and 15% which is ascribed to toxic effect as well as low achenes viability. The high viability of invasive T.minuta achenes, in addition to its salt tolerance, are two attributes related to its invasiveness.
There is general agreement that biodiversity in Yemen is under threat due to mechanized rain-fed ... more There is general agreement that biodiversity in Yemen is under threat due to mechanized rain-fed agricultural expansion, urban expansion, wood logging and overgrazing. For all these reasons, this study finds it urgent to provide this ecological assessment for the plant diversity and vegetation conservation in . The floristic composition and habitat information were recorded in 150 sample sites. The description of the floristic composition and diversity patterns of the study area was achieved by using of a range of species richness and abundance methods as well as diversity indices. The study area of West Taiz contains about 252 species (about 168 species per hectare) belonging to 57 families, with 12 dominant species (5 %), 5 endemic species, 14 near endemic species and 17 rare species. The investigated areasare estimated 1.5 ha, which corresponds to 150 samples X 100 m² sample sites. The largest families in terms of species in the study sites arePoaceae (Graminea) with 25 species, Euphorbiaceaewith 20 species, Apocynaceae with18 species, Acanthaceae with18 species, Fabaceae (Papilionoideae) with 12 species andMimosaceae with 11 species. The occurrence of species in different landforms of the study area shows a characteristic pattern: the total richness of 186 for mountains, 171 for hills, 155 for wadis and 118 for plains.
Developmental mutants serve as a useful material to unravel the mechanisms necessary for organ de... more Developmental mutants serve as a useful material to unravel the mechanisms necessary for organ development. The polycotyledon (poc) mutant of tomato, with multiple cotyledons in the seedling and varied phenotypic eVects in the adult plant is one such mutant. Studies using physiological and anatomical methods in our lab suggest that POC is involved in the negative regulation of polar auxin transport, which is likely the reason for the pleiotropic phenotype in the mutant. Because of the physiological signiWcance of the polycotyledon mutant described in this paper and also being Wrst of its kind in tomato and also other plant species, we are using a map-based cloning approach to map the polycotyledon gene. Molecular mapping of this locus using segregating interspeciWc F 2 mapping population localized polycotyledon gene close to TG424 marker on the long arm of chromosome 9. The closest marker mapped was a PCR marker identiWed in this study, E8A2 at a distance of 7.4 cM from the poc locus. The absence of tightly linked RAPD markers and the non-availability of more mapped markers in this region led us to initiate chromosome walk to poly-cotyledon gene. Both the Xanking markers TG248 and E8A2 were used to screen the BAC library and a con-tig was developed for TG248 marker. The BAC-end sequences were analyzed for their use as RFLP markers to enrich this region for markers. Analysis of the BAC-end sequences revealed that poc is localized in the region surrounded by copia-like retrotransposon elements explaining the absence of markers in the euchromatin region on long arm of chromosome 9. Further studies identiWed two BAC-end sequences which mapped around the poc locus and also indicated very low physical versus genetic distance ratio in this region. The double mutant analyses of poc with the other two known polycotyledon mutants of tomato, pct and dem revealed allelism with pct; therefore, the poc mutant was named as pct1-2, and also the original pct mutant was renamed as pct1-1.
Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. ... more Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. granatum L., were compared for the first time. Analysis of one P. protopunica and eleven P. grana-tum accessions was performed using three molecular markers, i.e., sequence related amplified polymor-phism (SRAP), target region amplification polymor-phism (TRAP), and intron targeted amplified polymorphism (ITAP), along with analysis of pgWD40 sequences, a gene involved in anthocyanin biosynthesis. All markers revealed the relationship between the two species and placed them at 33% similarity. SRAP, TRAP, and ITAP generated a total of 299, 260, and 160 bands, respectively. Of these, 78, 74, and 41 bands were specific for P. protopunica, and 92, 85, and 57 bands, respectively, were shared between both species. Sequence analysis of pgWD40*870 bp amplicons exhibited 100% identity among P. granatum accessions and 98% identity to that of P. protopunica. Phylogenetic analysis of WD40 sequences from monocot and dicot species, including both Punica species confirmed the relation between P. protopunica and P. granatum, supporting earlier reports that P. protopunica could be an ancestral species of P. granatum. Furthermore, the genetic diversity among and within P. granatum accessions from Egypt (3), Mexico (5), and Yemen (3) was assessed. Molecular marker-based relationships among region-bulked accessions was approximately the same (*90% similarity), whereas the degree of genetic variation was altered within each region. Specific bands (alleles) for accessions of each region along with those shared among them were identified. Thus, these bands could be used for pomegranate genotyping and breeding programs.
Yemen is the richest country in the Arabian Peninsula in its biodiversity at all levels; genes, s... more Yemen is the richest country in the Arabian Peninsula in its biodiversity at all levels; genes, species, ecosystems and traditional knowledge. It is believed that the two serious threats to biodiversity are habitat destruction and nonnative species invasion in any ecosystem. Inspite of the observed threats of exotic invasive plant species in Yemen, these plants continue to be unchecked and unmonitored. The objective of this study is to provide information and accurate identification of the most abundant exotic invasive plant species. Pilot survey of these plant species was carried out mainly in mountainous areas which is the most fragile ecosystems. Interviews with local people for primary assessment of the invasive plant species impact were also made, in addition to primary field observations. The results indicated that new invasive plant species were recorded in the country, although they are very abundant at this time, Parthenium hysterophorus was recorded for the first time in hillsides in Hajah. Parthenium hysterophorus is sensitizer causes many health problems to human and animals, it also strong allelopathic weed. This weed in addition to the unpalatable and allelopathic Tagetes minuta has replaced native grazing vegetation in escarpment and the last has also invested the wastelands, roadsides, grazing lands, and abandoned fields even at above elevation of 3000 m. Tagetes minuta has led to reduction in population of Acacia asak trees and other species in the invasion areas. Opuntia dillenii was found at Bura mountains at the core of the protected area, its very serious threat to biodiversity and it causes blindness to animals and human whom get in contact with it.
The polycotyledon mutant of tomato (Lycopersicon esculentum L. cv Ailsa Craig) showed altered dev... more The polycotyledon mutant of tomato (Lycopersicon esculentum L. cv Ailsa Craig) showed altered development during embryogenesis and during vegetative and reproductive phases. The phenotype was pleiotropic and included the formation of extra cotyledons, changes in leaf shape, increased number of flowers (indeterminacy) with abnormal floral organs, the formation of epiphyllous structures, and altered gravitropism. The earliest defects were observed at the transition from the globular to the heart stage of embryogenesis with the formation of multiple cotyledons. Epidermal cells in the mutant embryo were smaller and less expanded compared with wild type. Examination of polar auxin transport (PAT) showed a striking enhancement in the case of the mutant. Increase in PAT did not appear to be caused by a decrease in flavonoids because the mutant had normal flavonoid levels. Application of 2,3,5-triiodobenzoic acid, an inhibitor of polar transport of auxin, rescued postgermination phenotypes of young seedlings. Our analysis reveals a level of control that negatively regulates PAT in tomato and its contribution to plant development and organogenesis.
Mastery project مشروع اصلاح برامج اعداد معلمي العلوم واالرياضيات في اليمن , 2012
This chapter looks at the issues of Quality Assurance in MASTERY. It describes the activities und... more This chapter looks at the issues of Quality Assurance in MASTERY. It describes the activities undertaken to develop quality assurance tools and mechanisms which culminated in the evaluation of the programs and courses in 2010-2011. Introduction:
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