inderdeep kaur | University of Delhi (original) (raw)

Papers by inderdeep kaur

Journal of nursing & care, Mar 21, 2017

The International Journal of Developmental Biology

Synergids are metabolically dynamic cells of the egg apparatus and represent an important compone... more Synergids are metabolically dynamic cells of the egg apparatus and represent an important component of the female gametophyte. Besides directing the growth of the pollen tube towards the micropylar end of the embryo sac, these ephemeral structures make room for the pollen tube cytoplasm. The nature of chemotrophic substances that direct the growth of the pollen tube, the mechanism of degeneration of one of the synergids before fertilization and the molecular aspects of synergid morphogenesis have been studied in detail. Research carried out on model systems such as Arabidopsis, Brassica, Capsella, Triticum and Torenia has expanded our understanding of the molecular regulation of the pollen tube journey, its guidance and navigation in the pistil. Recently, the critical role of the central cell in fertilization and prevention of polytubey has also been thoroughly investigated. Interesting aspects that lead to degeneration of synergids, and the factors governing degeneration, including...

Journal of Nursing and Health, Jul 4, 2018

Proceedings of the Indian …, 1991

... Ultrastructure and histochemistry of vegetative Thallus in Sargassum vulgare C. Agardh and S.... more ... Ultrastructure and histochemistry of vegetative Thallus in Sargassum vulgare C. Agardh and S. johnstonii Setchell & Gardner. Auteur(s) / Author(s). VIJAYARAGHAVAN MR ; INDERDEEPKAUR ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). Univ. Delhi, dep. ...

Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexua... more Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexual conceptacles which open outside by ostiole, and wherein gametangia (antheridia or oogonia) lie interspersed with paraphyses. Since out-put of eggs is extremely low, 4- 6 per female conceptacle, Sargassum sp. ensures its survival under all eco-physiological conditions. The released oogonium is “wrapped ” in sulphated polysaccharide-rich wall layer known to provide protection against desiccation. Oogonia after being “extruded ” out of ostiole, are “incubated ” on receptacle, where they grow into eggs that are easily contacted by spermatozoids. Gamete release is synchronous and almost si-multaneous ensuring high rates of fertilization. The release occurs on days falling near a full moon or new moon, during low tides when conceptacles lie exposed. Gamete release occurs first from upper conceptacles, which “house ” mature gametangia while lower ones are still developing. This results in gam...

Reproductive Ecology of Flowering Plants: Patterns and Processes

Sexuality in flowering plants is distinctly correlated with mating systems. Maximum numbers of fl... more Sexuality in flowering plants is distinctly correlated with mating systems. Maximum numbers of flowering plants are outbreeders, and cross-pollination is the predominant type of pollen transfer to increase genetic variation. Morphological traits that promote outbreeding include temporal (dichogamy) and spatial separation (herkogamy) of male and female functions of flowers, monoecy and dioecy. Monoecy permits both inbreeding and outbreeding, while outbreeding is the only means of reproduction in dioecious species. Outbreeding confers on plant an opportunity to 'move' its genes amongst conspecific populations and is largely influenced by the availability of pollinators. Though pollinator-driven mating is favoured by most plant species, certain populations may occasionally maximize their reproductive fitness under adverse conditions by adopting multiple strategies such as autonomous selfing, dichogamy, late and early selfing, prepotency and outbreeding. Sexual plasticity manifested through mixed-mating, multiple mating, biparental inbreeding and sex switching has helped plants not only reproduce sexually but also 'move on'. In addition, pollination environment also alters the outcrossing rates in a population emphasizing the fact that mating systems are labile. How various populations maintain potential for such shifts needs to be investigated. This chapter focuses on the outbreeding strategies in plants and also discusses how mating systems may evolve over the next few decades in response to challenges presented by changing environment.

Indian journal of plant physiology, 2000

Seeds of V. radiata were sown in pots containing 0-7.5 g lead nitrate/kg soil. Plant height, root... more Seeds of V. radiata were sown in pots containing 0-7.5 g lead nitrate/kg soil. Plant height, root-shoot ratio, dry weight, nodule number per plant, protein content and nitrate reductase activity decreased with increasing lead concentration, while the stomatal index of leaves ...

Algae, 1998

The plants of Lobophora variegata (Lamouroux) Womersley ex Oliveira are small, flat, fan-shaped a... more The plants of Lobophora variegata (Lamouroux) Womersley ex Oliveira are small, flat, fan-shaped and lobed at maturity. Growth of the plant occurs by means of a series of marginal initials resulting in a thallus composed of three tissues: epidermis, cortex and medulla. The walls of all cell types show a mixture of carboxylated and sulphated polysaccharides whereas the cytoplasm reveals differential distribution of physodes, vacuoles, proteins, polysaccharides and plastids. The tetrasporangia occur in groups and the associated hairs are absent. The present taxonomic status of Lobophora variegata, which had earlier been placed under the genus Dictyota is pointed out with reasonable certainty. The elucidation of asexual and sexual reproduction will provide further evidence of taxonomic status of Lobophora.

Soil Biology

Healthy soil is a key component to growing high quality crops, and it is essential that we manage... more Healthy soil is a key component to growing high quality crops, and it is essential that we manage our soils well. This would be majorly possible with intensive inputs of fertilizers, and irrigation as well as integrated soil management. Fertilization of soil with chemical-based inputs which has been practiced by farmers since several decades, has challenged the very existence of humankind. Intensive eco-friendly fertilization of soil is, therefore, a major challenge in face of synthetic fertilizers opening up the pandora box of environmental degradation and health hazards. Climate change, loss of biodiversity, and urbanization have also emerged as serious challenges to farmers. New innovations in fertilizer options for soil management need to be worked out. To lift agricultural productivity and food supply, fertilizer availability and affordability is prime concern of both farmers and stakeholders. Better still would be to adopt an integrated approach to soil management. It would not only address issues of environmental quality and land degradation but would potentially improve agricultural production and crop quality. Macro algae commonly referred to as seaweeds have fast emerged as promising candidates in soil management practices and “green” agriculture. Besides eliciting a growth-promoting effect on plants, seaweeds also affect the physical, chemical, and biological properties of soil which in turn influence plant growth. Seaweeds in fresh and dried form and seaweed concentrates enhance soil health by improving moisture-holding capacity and by promoting the growth of beneficial soil microbes, besides fertilizing it.

ALGAE, 2005

Anatomical organization of Stoechospermum marginatum reveals small cortical cells with moderately... more Anatomical organization of Stoechospermum marginatum reveals small cortical cells with moderately dense cytoplasm, overlying a multilayered medulla comparatively poor in cytoplasmic contents. The anticlinal walls of cortical cells show local thickenings rich in alginic acids. Sori form on both thallus surfaces and show tetrasporangia, paraphyses and sterile-cells. The unicellular paraphyses are rich in sulphated polysaccharides whereas multicellular ones have abundance of not only polysaccharides, but also of vacuoles and phenols. The sterile-cells are modified cortical cells present on either side of the tetrasporangium and bear cytoplasmic strands towards soral cavity. Various stages of tetrasporogenesis are seen in a single sorus. The developing tetrasporangium shows a two layered wall, where the outer one is rich in alginic acid and inner has sulphated polysaccharides. An apical pad aids tetraspore release. Also involved in the release process are sterile-cells, paraphyses and polysaccharides.

The plants of Dictyopteris australis (Sonder) Askensay are large, ribbon-like, dichotomously bran... more The plants of Dictyopteris australis (Sonder) Askensay are large, ribbon-like, dichotomously branched with a distinct midrib : The wing portion of the thallus is 2 or 3 celled thick and midrib is about 5 celled thick. The deflexed lines of hairs borne on both surfaces of the thallus show tetrasporangia at various stages of development. Tetrasporangia are partially embeddded and possess at maturity, a three layered wall with varying amounts of alginic acid and sulphated polysaccharides. The tetrasporangial cytoplasm shows abundant physodes, sulphated polysaccharides and vacuoles of various shapes and sizes. A reduction division results in the formation of tetraspores which are released by a highly coordinated mechanism. The outer layer of the tetrasporangium ruptures and the middle layer forms a stalk, temporarily holding the released tetraspore mass to the parent thallus. The tetraspores which are initially enclosed in middle and inner layer are later set free. The older thalli also show the formation of vegetative plants that remain attached to the parent thallus by means of branched rhizoids.

American Journal of Plant Sciences, 2012

Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexua... more Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexual conceptacles which open outside by ostiole, and wherein gametangia (antheridia or oogonia) lie interspersed with paraphyses. Since output of eggs is extremely low, 4-6 per female conceptacle, Sargassum sp. ensures its survival under all ecophysiological conditions. The released oogonium is "wrapped" in sulphated polysaccharide-rich wall layer known to provide protection against desiccation. Oogonia after being "extruded" out of ostiole, are "incubated" on receptacle, where they grow into eggs that are easily contacted by spermatozoids. Gamete release is synchronous and almost simultaneous ensuring high rates of fertilization. The release occurs on days falling near a full moon or new moon, during low tides when conceptacles lie exposed. Gamete release occurs first from upper conceptacles, which "house" mature gametangia while lower ones are still developing. This results in gamete release over an extended period of time. The zygote dispersal and propagule recruitment also show adaptations selectively advantageous for the alga.

Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexua... more Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexual conceptacles which open outside by ostiole, and wherein gametangia (antheridia or oogonia) lie interspersed with paraphyses. Since output of eggs is extremely low, 4-6 per female conceptacle, Sargassum sp. ensures its survival under all ecophysiological conditions. The released oogonium is "wrapped" in sulphated polysaccharide-rich wall layer known to provide protection against desiccation. Oogonia after being "extruded" out of ostiole, are "incubated" on receptacle, where they grow into eggs that are easily contacted by spermatozoids. Gamete release is synchronous and almost simultaneous ensuring high rates of fertilization. The release occurs on days falling near a full moon or new moon, during low tides when conceptacles lie exposed. Gamete release occurs first from upper conceptacles, which "house" mature gametangia while lower ones are still developing. This results in gamete release over an extended period of time. The zygote dispersal and propagule recruitment also show adaptations selectively advantageous for the alga.

Journal of Applied Phycology, 2013

This study was aimed at developing a protocol for improving soil health using Sargassum johnstoni... more This study was aimed at developing a protocol for improving soil health using Sargassum johnstonii as a conditioner and fertilizer. Tomato (Lycopersicon esculentum) plants were raised on seaweed-amended soil in experimental fields of Department of Botany, University of Delhi, India. Soil was amended with granular (G) and powder (P) seaweed forms in the proportion of 12.5 % (G1 and P1), 25 % (G2 and P2), and 37.5 % (G3 and P3) (w/w). To compare the efficacy of seaweed fertilizer with a conventional organic fertilizer, a parallel series (positive control) was run with vermicompost (V) in the above-mentioned proportions. Unamended soil served as control (C). The nutrient status of S. johnstonii and vermicompost was analyzed prior to giving treatments. Physicochemical properties of the amended soils as well as growth, productivity, and biochemical constituents of tomato grown in soil with each treatment were analyzed. Higher concentration of granular form of seaweed (G3) in the soil resulted in 144, 268, 122, 138, and 188 % increase in Na, K, Mg, Ca, and Zn, respectively. Seaweed-amended soil had higher porosity and water-holding capacity as compared to C. Tomato plants raised on seaweed (G3 and P3)-amended soil showed an increased overall growth, with earlier flowering and fruiting as compared to control plants. Plants raised on G3-amended soil showed significantly higher levels of proteins (95 mg g−1 FW) in leaves, and vitamin C (99.2 mg 100 g−1) and lycopene (5.78 mg 100 g−1) in fruits. The present study showed that S. johnstonii biomass has a high potential to condition and fertilize the soil for improved crop productivity.

Journal of nursing & care, Mar 21, 2017

The International Journal of Developmental Biology

Synergids are metabolically dynamic cells of the egg apparatus and represent an important compone... more Synergids are metabolically dynamic cells of the egg apparatus and represent an important component of the female gametophyte. Besides directing the growth of the pollen tube towards the micropylar end of the embryo sac, these ephemeral structures make room for the pollen tube cytoplasm. The nature of chemotrophic substances that direct the growth of the pollen tube, the mechanism of degeneration of one of the synergids before fertilization and the molecular aspects of synergid morphogenesis have been studied in detail. Research carried out on model systems such as Arabidopsis, Brassica, Capsella, Triticum and Torenia has expanded our understanding of the molecular regulation of the pollen tube journey, its guidance and navigation in the pistil. Recently, the critical role of the central cell in fertilization and prevention of polytubey has also been thoroughly investigated. Interesting aspects that lead to degeneration of synergids, and the factors governing degeneration, including...

Journal of Nursing and Health, Jul 4, 2018

Proceedings of the Indian …, 1991

... Ultrastructure and histochemistry of vegetative Thallus in Sargassum vulgare C. Agardh and S.... more ... Ultrastructure and histochemistry of vegetative Thallus in Sargassum vulgare C. Agardh and S. johnstonii Setchell & Gardner. Auteur(s) / Author(s). VIJAYARAGHAVAN MR ; INDERDEEPKAUR ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). Univ. Delhi, dep. ...

Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexua... more Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexual conceptacles which open outside by ostiole, and wherein gametangia (antheridia or oogonia) lie interspersed with paraphyses. Since out-put of eggs is extremely low, 4- 6 per female conceptacle, Sargassum sp. ensures its survival under all eco-physiological conditions. The released oogonium is “wrapped ” in sulphated polysaccharide-rich wall layer known to provide protection against desiccation. Oogonia after being “extruded ” out of ostiole, are “incubated ” on receptacle, where they grow into eggs that are easily contacted by spermatozoids. Gamete release is synchronous and almost si-multaneous ensuring high rates of fertilization. The release occurs on days falling near a full moon or new moon, during low tides when conceptacles lie exposed. Gamete release occurs first from upper conceptacles, which “house ” mature gametangia while lower ones are still developing. This results in gam...

Reproductive Ecology of Flowering Plants: Patterns and Processes

Sexuality in flowering plants is distinctly correlated with mating systems. Maximum numbers of fl... more Sexuality in flowering plants is distinctly correlated with mating systems. Maximum numbers of flowering plants are outbreeders, and cross-pollination is the predominant type of pollen transfer to increase genetic variation. Morphological traits that promote outbreeding include temporal (dichogamy) and spatial separation (herkogamy) of male and female functions of flowers, monoecy and dioecy. Monoecy permits both inbreeding and outbreeding, while outbreeding is the only means of reproduction in dioecious species. Outbreeding confers on plant an opportunity to 'move' its genes amongst conspecific populations and is largely influenced by the availability of pollinators. Though pollinator-driven mating is favoured by most plant species, certain populations may occasionally maximize their reproductive fitness under adverse conditions by adopting multiple strategies such as autonomous selfing, dichogamy, late and early selfing, prepotency and outbreeding. Sexual plasticity manifested through mixed-mating, multiple mating, biparental inbreeding and sex switching has helped plants not only reproduce sexually but also 'move on'. In addition, pollination environment also alters the outcrossing rates in a population emphasizing the fact that mating systems are labile. How various populations maintain potential for such shifts needs to be investigated. This chapter focuses on the outbreeding strategies in plants and also discusses how mating systems may evolve over the next few decades in response to challenges presented by changing environment.

Indian journal of plant physiology, 2000

Seeds of V. radiata were sown in pots containing 0-7.5 g lead nitrate/kg soil. Plant height, root... more Seeds of V. radiata were sown in pots containing 0-7.5 g lead nitrate/kg soil. Plant height, root-shoot ratio, dry weight, nodule number per plant, protein content and nitrate reductase activity decreased with increasing lead concentration, while the stomatal index of leaves ...

Algae, 1998

The plants of Lobophora variegata (Lamouroux) Womersley ex Oliveira are small, flat, fan-shaped a... more The plants of Lobophora variegata (Lamouroux) Womersley ex Oliveira are small, flat, fan-shaped and lobed at maturity. Growth of the plant occurs by means of a series of marginal initials resulting in a thallus composed of three tissues: epidermis, cortex and medulla. The walls of all cell types show a mixture of carboxylated and sulphated polysaccharides whereas the cytoplasm reveals differential distribution of physodes, vacuoles, proteins, polysaccharides and plastids. The tetrasporangia occur in groups and the associated hairs are absent. The present taxonomic status of Lobophora variegata, which had earlier been placed under the genus Dictyota is pointed out with reasonable certainty. The elucidation of asexual and sexual reproduction will provide further evidence of taxonomic status of Lobophora.

Soil Biology

Healthy soil is a key component to growing high quality crops, and it is essential that we manage... more Healthy soil is a key component to growing high quality crops, and it is essential that we manage our soils well. This would be majorly possible with intensive inputs of fertilizers, and irrigation as well as integrated soil management. Fertilization of soil with chemical-based inputs which has been practiced by farmers since several decades, has challenged the very existence of humankind. Intensive eco-friendly fertilization of soil is, therefore, a major challenge in face of synthetic fertilizers opening up the pandora box of environmental degradation and health hazards. Climate change, loss of biodiversity, and urbanization have also emerged as serious challenges to farmers. New innovations in fertilizer options for soil management need to be worked out. To lift agricultural productivity and food supply, fertilizer availability and affordability is prime concern of both farmers and stakeholders. Better still would be to adopt an integrated approach to soil management. It would not only address issues of environmental quality and land degradation but would potentially improve agricultural production and crop quality. Macro algae commonly referred to as seaweeds have fast emerged as promising candidates in soil management practices and “green” agriculture. Besides eliciting a growth-promoting effect on plants, seaweeds also affect the physical, chemical, and biological properties of soil which in turn influence plant growth. Seaweeds in fresh and dried form and seaweed concentrates enhance soil health by improving moisture-holding capacity and by promoting the growth of beneficial soil microbes, besides fertilizing it.

ALGAE, 2005

Anatomical organization of Stoechospermum marginatum reveals small cortical cells with moderately... more Anatomical organization of Stoechospermum marginatum reveals small cortical cells with moderately dense cytoplasm, overlying a multilayered medulla comparatively poor in cytoplasmic contents. The anticlinal walls of cortical cells show local thickenings rich in alginic acids. Sori form on both thallus surfaces and show tetrasporangia, paraphyses and sterile-cells. The unicellular paraphyses are rich in sulphated polysaccharides whereas multicellular ones have abundance of not only polysaccharides, but also of vacuoles and phenols. The sterile-cells are modified cortical cells present on either side of the tetrasporangium and bear cytoplasmic strands towards soral cavity. Various stages of tetrasporogenesis are seen in a single sorus. The developing tetrasporangium shows a two layered wall, where the outer one is rich in alginic acid and inner has sulphated polysaccharides. An apical pad aids tetraspore release. Also involved in the release process are sterile-cells, paraphyses and polysaccharides.

The plants of Dictyopteris australis (Sonder) Askensay are large, ribbon-like, dichotomously bran... more The plants of Dictyopteris australis (Sonder) Askensay are large, ribbon-like, dichotomously branched with a distinct midrib : The wing portion of the thallus is 2 or 3 celled thick and midrib is about 5 celled thick. The deflexed lines of hairs borne on both surfaces of the thallus show tetrasporangia at various stages of development. Tetrasporangia are partially embeddded and possess at maturity, a three layered wall with varying amounts of alginic acid and sulphated polysaccharides. The tetrasporangial cytoplasm shows abundant physodes, sulphated polysaccharides and vacuoles of various shapes and sizes. A reduction division results in the formation of tetraspores which are released by a highly coordinated mechanism. The outer layer of the tetrasporangium ruptures and the middle layer forms a stalk, temporarily holding the released tetraspore mass to the parent thallus. The tetraspores which are initially enclosed in middle and inner layer are later set free. The older thalli also show the formation of vegetative plants that remain attached to the parent thallus by means of branched rhizoids.

American Journal of Plant Sciences, 2012

Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexua... more Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexual conceptacles which open outside by ostiole, and wherein gametangia (antheridia or oogonia) lie interspersed with paraphyses. Since output of eggs is extremely low, 4-6 per female conceptacle, Sargassum sp. ensures its survival under all ecophysiological conditions. The released oogonium is "wrapped" in sulphated polysaccharide-rich wall layer known to provide protection against desiccation. Oogonia after being "extruded" out of ostiole, are "incubated" on receptacle, where they grow into eggs that are easily contacted by spermatozoids. Gamete release is synchronous and almost simultaneous ensuring high rates of fertilization. The release occurs on days falling near a full moon or new moon, during low tides when conceptacles lie exposed. Gamete release occurs first from upper conceptacles, which "house" mature gametangia while lower ones are still developing. This results in gamete release over an extended period of time. The zygote dispersal and propagule recruitment also show adaptations selectively advantageous for the alga.

Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexua... more Sargassum vulgare C. Agardh shows androgynous receptacles, each bearing on an average 12 unisexual conceptacles which open outside by ostiole, and wherein gametangia (antheridia or oogonia) lie interspersed with paraphyses. Since output of eggs is extremely low, 4-6 per female conceptacle, Sargassum sp. ensures its survival under all ecophysiological conditions. The released oogonium is "wrapped" in sulphated polysaccharide-rich wall layer known to provide protection against desiccation. Oogonia after being "extruded" out of ostiole, are "incubated" on receptacle, where they grow into eggs that are easily contacted by spermatozoids. Gamete release is synchronous and almost simultaneous ensuring high rates of fertilization. The release occurs on days falling near a full moon or new moon, during low tides when conceptacles lie exposed. Gamete release occurs first from upper conceptacles, which "house" mature gametangia while lower ones are still developing. This results in gamete release over an extended period of time. The zygote dispersal and propagule recruitment also show adaptations selectively advantageous for the alga.

Journal of Applied Phycology, 2013

This study was aimed at developing a protocol for improving soil health using Sargassum johnstoni... more This study was aimed at developing a protocol for improving soil health using Sargassum johnstonii as a conditioner and fertilizer. Tomato (Lycopersicon esculentum) plants were raised on seaweed-amended soil in experimental fields of Department of Botany, University of Delhi, India. Soil was amended with granular (G) and powder (P) seaweed forms in the proportion of 12.5 % (G1 and P1), 25 % (G2 and P2), and 37.5 % (G3 and P3) (w/w). To compare the efficacy of seaweed fertilizer with a conventional organic fertilizer, a parallel series (positive control) was run with vermicompost (V) in the above-mentioned proportions. Unamended soil served as control (C). The nutrient status of S. johnstonii and vermicompost was analyzed prior to giving treatments. Physicochemical properties of the amended soils as well as growth, productivity, and biochemical constituents of tomato grown in soil with each treatment were analyzed. Higher concentration of granular form of seaweed (G3) in the soil resulted in 144, 268, 122, 138, and 188 % increase in Na, K, Mg, Ca, and Zn, respectively. Seaweed-amended soil had higher porosity and water-holding capacity as compared to C. Tomato plants raised on seaweed (G3 and P3)-amended soil showed an increased overall growth, with earlier flowering and fruiting as compared to control plants. Plants raised on G3-amended soil showed significantly higher levels of proteins (95 mg g−1 FW) in leaves, and vitamin C (99.2 mg 100 g−1) and lycopene (5.78 mg 100 g−1) in fruits. The present study showed that S. johnstonii biomass has a high potential to condition and fertilize the soil for improved crop productivity.