Morpho-taxonomic description of cypsela features in two genera of tribe Mutisieae (Asteraceae)

Micro-morphological, macro-morphological, anatomical features of cypsela features of two genera Leibnitzia nepalensis (Kuntze)Kitam. And Onoseris sagittatus  Rusby of tribe Mutisieae of family Asteraceae have been investigated by using light and scanning electron microscopy. Cypsela homomorphic and carpopodium symmetric in both genera. Cypsela narrow elliptic in cross section, ribbed. However, in Leibnitzia, cypsela slightly curved with ill-developed ribs; hairs sparsely distributed; stylopodium ill-developed; carpopodium diameter is comparable to the base of the cypsela; insertion of cypsela oblique;  pappus basally united; cypsela elliptic in T.S.; epicarpic cuticle absent; mesocarpic parenchyma absent; secretory ducts in each cotyledon equal in size. Contrastingly, in Onoseris, cypsela straight; ribs prominent; hairs densely distributed; stylopodium well-developed; diameter of carpopodium lesser than the base of the cypsela; insertion of cypsela straight;  pappus basally free; cypsela angular in T.S.; epicarpic cuticle present; mesocarpic parenchyma present; secretory ducts in each cotyledon unequal in size

Flavonoid-Deficient Mutants in Grass Pea (Lathyrus sativus L.): Genetic Control, Linkage Relationships, and Mapping with Aconitase and S-Nitrosoglutathione Reductase Isozyme Loci

Two flavonoid-deficient mutants, designated as fldL-1 and fldL-2, were isolated in EMS-mutagenized (0.15%, 10 h) M2 progeny of grass pea (Lathyrus sativus L.). Both the mutants contained total leaf flavonoid content only 20% of their mother varieties. Genetic analysis revealed monogenic recessive inheritance of the trait, controlled by two different nonallelic loci. The two mutants differed significantly in banding patterns of leaf aconitase (ACO) and S-nitrosoglutathione reductase (GSNOR) isozymes, possessing unique bands in Aco 1, Aco 2, and Gsnor 2 loci. Isozyme loci inherited monogenically showing codominant expression in F2 (1 : 2 : 1) and backcross (1 : 1) segregations. Linkage studies and primary trisomic analysis mapped Aco 1 and fld 1 loci on extra chromosome of trisomic-I and Aco 2, fld 2, and Gsnor 2 on extra chromosome of trisomic-IV in linked associations

Exogenous thiourea modulates antioxidant defence and glyoxalase systems in lentil genotypes under arsenic stress

Arsenic (As) is a wide-spread toxic and carcinogenic metalloid, affecting crop productivity worldwide. Lentil, an edible grain legume, is increasingly exposed to soil arsenic contamination. However, our understandings regarding mechanistic details and mitigation strategies against arsenic toxicity in edible legume are extremely poor. Main purpose of the present study was to investigate the As-effects and its mitigation by thiourea (TU), a sulfhydryl bioregulator, in lentil. Four widely grown lentil genotypes were grown in nutrient media, supplemented with 30 μM sodium arsenate (As), As + 6.5 mM TU and As + 13 mM TU, keeping an untreated control for 10 d. As severely affected plant dry weight by accumulating in shoots and roots. However, TU application sequestered As in crop roots and prevented up-ward translocation of As. TU coordinately modulated glyoxalase system I and II (Gly I and II) and ascorbate (AsA)-glutathione (GSH) redox, and antioxidant defense enzymes in both leaves and roots of four genotypes. Elevation of Gly system prevented toxic methyl glyoxal overaccumulation whereas stimulated AsA-GSH cycle enzymes and Glutathione s-transferase and catalase effectively scavenged H2O2 and prevented reactive oxygen species (ROS) -mediated onset of oxidative damage in four genotypes, as was evident from ROS-imaging study. Results suggested exogenous TU stimulated the Gly and antioxidant defense in fine tune against As-induced oxidative damage in lentil genotypes

RETRACTED: RAPD-based DNA fingerprinting in Lantana camara L. ecotypes and development of a digital database platform ‘LANRAD’

Retraction of: Talukdar, T and Talukdar, D. 2016. Plant Science Today 3(2): 72-8

Effect of arsenic-induced toxicity on morphological traits of Trigonella foenum-graecum L. and Lathyrus sativus L. during germination and early seedling growth.

Abstract: Effect of five different concentrations (0, 10, 20, 30 and 40 mg/L) of arsenic was studied on 11 different parameters of two important leguminous crops, namely Trigonella foenum-graecum L. (fenugreek) and Lathyrus sativus L. (grass pea) during germination and early seedling growth stage. Mean value of germination percentage, germination index and relative germination rate decreased with concomitant increase in arsenic-induced injury level in increasing concentration of arsenic in both plants and the effect was significant at 30 and 40 mg/L treatments. Fresh and dry weight of shoots, roots and their length also reduced significantly in these two treatment levels. There was significant accumulation of arsenic in tissues, and the effect was more severe on root than shoots. Based on the parameters responding to arsenic-induced stress, Arsenic Response Index (ARI) was developed for the first time in these two crops. Among the two crops, T. foenum-graecum L. exhibited better tolerance to arsenic-induced toxicity than L. sativus L. Considering mean and ARI value, 30 mg/L of arsenic was selected as toxic to L. sativus L., while the limit was 40 mg/L for T. foenum-graecum L. at the stages of germination and early seedling growth

Cytogenomics and Mutagenomics in Plant Functional Biology and Breeding

One of the most important breakthroughs in the history of genetics and plant breeding was the development of plant cytology and experimental mutagenesis, which later brought about plant cytogenetics and mutation breeding and now they have entered in functional biology era with the unprecedented development of plant molecular cytogenetics, genetics, and functional genomics. Application of cell biology particularly chromosome biology in the fields of plant genome structure and function has ushered the development of plant cytogenomics. Development of advanced technology like DNA base-specific fluorescence banding, GISH, and FISH-based chromosome painting has greatly facilitated the identification, localization, and mapping of chromosome-specific markers in plants, which is of high importance in plant molecular systematics, species identification, detection of hybrid nature, alien chromosomes and chromosomal aberrations, analysis of somaclonal variations, and diversity analysis. The dynamism of chromatin architecture and cell cycle, representing chromosome functional biology, is another important part of plant cytogenomics. On the other hand, mutagenomics is defined as applied mutation breeding, in which genomic information and tools are utilized in the designing of breeding strategies, screening, selection and verification/authentication of natural and induced mutants, and the utilization of desirable mutations in the breeding processes. Considerable progress has been made in recent times in breeding of cereals, legumes, oil seeds, vegetables, horticultural crops, spices and condiments, fiber-yielding plants, and medicinal and aromatic plants for diverse types of desirable agronomic and functional traits including disease and abiotic stress resistance/tolerance; herbicide resistance; lowering of anti-nutritional factors; enhancement of proteins, minerals, vitamins, essential amino acids, flavonoids, antioxidants, and dietary fibers; enrichment of soil nutrition; enhancement of ornamental, medicinal, and aromatic values; and development of functional and therapeutic foods and other diverse traits related to nutritional quality and high yield. This can be found in a mutant population which carries variant forms of potentially each and every gene present in a particular genome. The functionality of mutagenomics is greatly enhanced due to integration of classical mutagenesis with modern “omics” technology through the development of desirable diploid mutants, recombinant inbred lines, and aneuploid and polyploid lines as effective cytogenetic tools, utilizable in genome mapping and analysis. Functional sets of aneuploid tools are now available in different edible plants, through which several morphological, biochemical, and molecular traits/markers have been assigned on definite chromosomes to construct linkage maps. Recently, induced mutations showing alterations in antioxidant defense response have been identified and tested against diverse types of abiotic stresses to reveal intrinsic cellular and metabolic events toward sensitivity of seed plants to salinity, drought, metal toxicity, and other stresses. These mutations are giving vital inputs, which can be used in formulating effective breeding strategies in different agroclimatic conditions. Mutagenized population has revealed altered pattern of genome response and can also be exploited in enhancing production of natural plant products like antioxidants and flavonoids. Furthermore, these large mutant populations have the potential in reverse genetics approach by employing various techniques, particularly “Targeting Induced Local Lesions in Genomics (TILLING)” technology to better understand gene functions through high-throughput mutation screening, and have been successfully used in major crop plants along with model plant Arabidopsis. The development of mutagenomic approach, thus, provides a cost-effective, clean, and easy-to-use functional tool to increase the genetic diversity and in utilization of this diversity in plant molecular mutation breeding through modern genomic methods

Floral diversity and ecology in Kalyani area of Nadia district, West Bengal, India

An assessment of plant diversity was carried out to record different species of flowering plants (Angiosperms) in Kalyani township of Nadia district, West Bengal, India during January, 2014. All together 6 quadrats were laid down, and 30 flowering plant species belonging to 15 families were documented. Voucher specimens were preserved and digitized in departmental phyto-informatics center. Frequency and density varied greatly among the taxa, while many species were not evenly abundant in the study area. Out of total species, 11 species can be used as economic and medicinal plants. There are also some alien invasive species of diverse origin

Ethno-medicinal uses of plants by tribal communities in Hili block of Dakshin Dinajpur district, West Bengal

110-118Use of plants by different ethnic tribal communities for treatment of various ailments in ‘Hili’ block of Dakshin Dinajpur district of West Bengal, India has been documented. As many as 62 plant species belonging to 34 families (61 Angiosperms and one fern), used by Santhal, Oraon, <i style="mso-bidi-font-style: normal">Munda and other communities (Polia, Sabar, <i style="mso-bidi-font-style: normal">Lodha) for medicinal purposes were identified. Largest number of plants was found in the family Fabaceae (8), followed by Amaranthaceae and Euphorbiaceae (4 each), Acanthaceae, Apocynaceae, Asteraceae, Rubiaceae and Poaceae (3 each). Malvaceae, Scrophulariaceae, Cucurbitaceae, Moraceae and Polygonaceae contained two plants each, while rest of the families possessed one plant each. The common health problems such as fever, diarrhoea and dysentery, indigestion and respiratory troubles dominated among the tribes for which herbal medicines were used. Significantly, fairly high numbers of plants have been used in treating sexually transmitted diseases and diabetes. Among the plant parts, leaves have been used most frequently by ethnic peoples, of which Santhals were the best among tribal communities under study in acquiring, maintaining and using traditional knowledge of herbal plants

Leaf Rolling and Stem Fasciation in Grass Pea (Lathyrus sativus L.) Mutant Are Mediated through Glutathione-Dependent Cellular and Metabolic Changes and Associated with a Metabolic Diversion through Cysteine during Phenotypic Reversal

A Lathyrus sativus L. mutant isolated in ethylmethane sulfonate-treated M2 progeny of mother variety BioL-212 and designated as rlfL-1 was characterized by inwardly rolled-leaf and stem and bud fasciations. The mutant exhibited karyomorphological peculiarities in both mitosis and meiosis with origin of aneuploidy. The mitosis was vigorous with high frequency of divisional cells and their quick turnover presumably steered cell proliferations. Significant transcriptional upregulations of cysteine and glutathione synthesis and concomitant stimulations of glutathione-mediated antioxidant defense helped rlfL-1 mutant to maintain balanced reactive oxygen species (ROS) metabolisms, as deduced by ROS-imaging study. Glutathione synthesis was shut down in buthionine sulfoximine- (BSO-) treated mother plant and mutant, and leaf-rolling and stems/buds fasciations in the mutant were reversed, accompanied by normalization of mitotic cell division process. Antioxidant defense was downregulated under low glutathione-redox but cysteine-desulfurations and photorespiratory glycolate oxidase transcripts were markedly overexpressed, preventing cysteine overaccumulation but resulted in excess H2O2 in BSO-treated mutant. This led to oxidative damage in proliferating cells, manifested by severe necrosis in rolled-leaf and fasciated stems. Results indicated vital role of glutathione in maintaining abnormal proliferations in plant organs, and its deficiency triggered phenotypic reversal through metabolic diversions of cysteine and concomitant cellular and metabolic modulations