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The Sikkim-Himalaya represents one of the unique reservoirs of rice genetic resources in India owing to the presence of a large number of landraces adapted to extreme climatic and edaphic conditions. This valuable gene pool is now under threat due to the introduction of high-yielding varieties, wanting suitable genetic intervention for enhancing their productivity, and thus economic viability. Development of lodging resistant, high-yielding varieties tolerant to soil acidity through association mapping aided marker-assisted breeding programmes can help achieve this in a fast and efficient manner. But this requires information on genetic diversity, population structure, etc., of the germplasm collection, which is strikingly lacking. We, therefore, characterized a set of 53 rice landraces from Sikkim to address the above issues. The results revealed moderate diversity, poor divergence and high gene flow in our germplasm collection attesting its utility as an association mapping panel. Further, a total of 115 putative marker-trait associations (P < 0.05, R2 ≥ 10%) were obtained using the general linear model and mixed linear models of which 25 were identical in both. Some of the associated markers were positioned in those regions where Qualitative Trait Loci have been previously identified in rice, providing credence to our results. The resources generated from this study will benefit the rice breeders from this region and elsewhere for targeting the yield and related traits, in addition to conservation efforts by the interested researchers.

The tropical legume Mucuna pruriens (L.) DC. is one of the protein-rich crops well suited for the arid regions of the world, which suffers from low soil fertility and protein-energy malnutrition. Though thought to have originated in Southern China or Eastern India, which includes parts of Northeast (NE) India, the genetic diversity of M. pruriens from this region is poorly documented. In this study, we used 25 species-specific genic-microsatellite markers to investigate the diversity and population structure of sixty (60) M. pruriens accessions from Northeast India alongside assessing variability for the six seed-based economic traits. The study revealed high genetic diversity (I = 0.496), poor population differentiation (GST = 0.038 and FST = 0.061), extensive gene flow (Nm = 7.48), and admixture genotypes in addition to good variability for the seed-based economic traits. These findings will provide a strong basis for future studies on association mapping in addition to broadening the germplasm base for breeding programs in this lesser-known legume crop.

Velvet bean (Mucuna pruriens var. utilis) offers significant economic benefits to tropical agriculture as food, fodder and medicinal crop; but suffers from poor breeding efforts. The genetic diversity and taxonomic confusion prevailing in this plant are not well investigated so far. In this study, we used a set of 43 transcriptome derived genic-microsatellite markers on a panel of 18 pan-India velvet bean accessions to determine the genomic composition and population structure. The results revealed low to moderate genetic diversity (average Ht = 0.25), low population differentiation (Fst: 0.05) and a high estimate of gene flow (Nm: 4.71). Extensive admixture and absence of clear-cut population structure characterize this set of collection. The results underscore the need for comprehensive pre-breeding efforts to broaden the genetic diversity of this important medicinal legume crop.

Rice (O. sativa L.) is one among the necessary food crops worldwide. Due to ever-increasing demand, many are undertaking several efforts to enhance its productivity - the latest being the sequel of Rice genome sequencing projects. The accelerated developments in next-generation sequencing (NGS) has bolstered these efforts in hundreds to thousands of rice varieties, which has enabled researchers to unpack the hidden potential of vast and diverse rice germplasm. One of the important objectives of these projects is to accurately characterize the gene models, which has a major significance for the in-depth study of gene function and, thus, various applications. Bioinformatics plays a major role in gene structure identification and its biological function through various algorithms and software. Hence, this chapter aims to elucidate the approach of identifying, characterizing, and finding the function of different types of rice genes.

Medicinal legume Mucuna pruriens L. (DC.) is an ecologically and economically important species known world-wide for anti-Parkinson's drug L-Dopa. The plant is native to eastern India which includes parts of northeast India where it has long history of cultivation. Recently, with the discovery of novel medicinal properties and agronomic benefits, the prospects for its large-scale cultivation in the region is growing necessitating development of improved cultivars. However, little data is available on genetic diversity and population structure from its native range to use as resource base for future molecular breeding works and conservation planning. Here we describe first empirical study on genetic diversity and gene flow of M.pruriens from northeast India based on AFLP markers. The high estimates of Jaccard's coefficient and Shannon's index reveal good genetic diversity supporting centre of origin theory. However, pair-wise estimates of genetic differentiation (FST, Nei's D) were low and AMOVA revealed no evidence for genetic structuring suggesting high levels of gene flow and absence of genetic drift or bottleneck events. Clustering based on UPGMA and STRUCTURE analyses were in conformity with these findings, but point to existence of two independent gene pools representing perhaps Assam plains and eastern Himalayas – the two disparate components of geographically diverse northeast India. The mechanisms underlying such variation besides implications on genetic diversity along with scope for future investigations are discussed.

Silk Banana is amongst the most popular groups of bananas grown in different parts of the world. However, the commercial scale cultivation requires identification of superior genotypes with desirable attributes including growth, yield, quality and resistance to Panama wilt disease which is a major concern. Panama disease caused by the fungus Fusarium oxysporum f. sp. cubense has been wreaking havoc in banana plantations throughout the world. A large number of varieties fall prey to the pathogen and hence world’s banana production has been threatened to a considerable extent, Silk Banana being the most vulnerable. Long term use of chemicals has not only failed to provide protection against the disease but has also raised concern about the environmental health. Resistance breeding is thus only viable alternative; however, breeding in banana is hindered by a number of inherent problems. In this communication, a systematic approach was proposed taking a typical case of Silk Banana var. Nanjanagud Rasabale to preselect lines possessing Panama wilt resistance and other desired traits. The proposed methodology comprised of identification of spontaneous variants in growing regions of the variety and their subsequent screening using a multi-pronged strategy. A number of lines exhibiting superiority in terms of tolerance to panama wilt, precocity, plant stature, physicochemical and shelf life related attributes have been reported. Considering overall performance, six promising lines were identified. This methodology has wider applicability as it could be effectively exploited with suitable modifications for identifying lines with desired traits in other varieties of banana.

Mucuna pruriens is a nutritionally and pharmaceutically important underutilized legume belonging to genus Mucuna of Leguminosae family. Extensive intraspecific diversity and adverse morphological features among the members have led to taxonomical confusions in the species. A total of 12 Mucuna pruriens accessions including its two botanical varieties, var. pruriens and var. utilis with six accessions each were analyzed to characterize the intraspecific diversity among them using the three barcode markers viz. ITS2, matK and trnHpsbA. Extensive intraspecific sequence diversity was observed in the trnHpsbA region, where as ITS2 and matK exhibited significant conserved regions. Such intraspecific sequence diversity is a limitation in adapting trnHpsbA as barcode as it may lead to misinterpretations, but in the present study an attempt has been made to extrapolate this diversity to explain within the species variations among Mucuna pruriens genotypes. Intraspecific sequence variations exhibited by trnHpsbA sequences were 83% in correlation with morphological features. The between groups mean distance of var. pruriens and var. utilis was found to be 0.346. Results of this study will complement with the existing molecular, morphological, ytological and biochemical markers towards Velvet bean improvement programs.

Xanthomonas campestris pv. dieffenbachiae, the causal agent of anthurium bacterial blight, is a major concern of the anthurium industry worldwide. This pathogen has many hosts in the family Araceae (e.g., Anthurium, Dieffenbachia, Syngonium, Aglaonema, Philodendron, Xanthosoma, Caladium, and Colocasia). Most anthurium cultivars are susceptible to bacterial blight, making it very difficult to manage the disease once introduced to a production area. Therefore, sanitation and exclusion of the pathogen through pathogen-free propagative stock are vital aspects of anthurium cultivation. The anthurium industry is expanding in India, and as many new cultivars are being imported, the plant material is subject to thorough quarantine inspection at the port of arrival. During routine inspections on three separate occasions, Anthurium andreanum plants imported from The Netherlands had watersoaked spots at leaf margins bordered by chlorotic or necrotic zones. Xanthomonas-like colonies were isolated from four different cultivars with semiselective media (2). Bacteriological tests confirmed that the cultures were X. campestris. Pathogenicity tests, performed by rubbing leaves with a cotton swab dipped into a suspension of the bacteria (approx. 107 CFU/ml), resulted in production of leafspots in 6 days and early blight symptoms in 10 to 12 days. The bacterium was further identified as X. campestris by carbon source utilization (similarity coefficient = 0.582; Biolog, Hayward, CA). Enzyme-linked immunosorbent assay reaction patterns with a panel of monoclonal antibodies for X. campestris pv. dieffenbachiae designated as Xcd1 (clone 72E-E3-B9-C5, isotype IgG2a), Xcd2 (clone 97-2-1-01, isotype IgM), Xcd3 (clone 72B-F9-B6-E9, isotype IgM), Xcd7 (clone72D-E10-C2-D9, isotype IgM), T1 (clone 92-16, isotype IgM), and T2 (clone 92-59-1-1, isotype IgG) showed that the intercepted strain belong to the serogroup 5 of X. campestris pv. dieffenbachiae (1). This pathogen is not known to occur in India, and there is high probability of risk of introduction through large-scale import of anthurium plants with either visible or latent infections. References: (1) R. L. Lipp et al. Phytopathology 82:677, 1992. (2) D. J. Norman and A. Alvarez. Plant Dis. 73:654, 1989.

Micropropagation of banana has become a routine procedure but high production cost is limiting the commercial use of tissue culture technology. Analytical grade sucrose is the most commonly used carbon source for the micropropagation banana, however, the cost is too high to justify the use at commercial scale. Therefore, inexpensive and readily available sources of carbon such as laboratory grade sucrose, common grade sugar, cube sugar, rock sugar, candy sugar, glucose, jaggery and sugarcane juice were evaluated for in vitro propagation of banana cv. 'GRANDE NAINE'. Best response in terms of shoot multiplication and rooting were achieved with rock sugar and common grade sugar, respectively which could be compared well with that of analytical grade sucrose. The results showed the possibility of successful use of cheaper carbon sources for micropropagation of banana cv. 'GRANDE NAINE'.

Cost of production is always stressed as the main obstacle for tissue culture. Nutrient media is one of the most costly input which accounts for 30-35 per cent of total cost of tissue culture propagation. Production cost, therefore, can be reduced by efficient utilization of culture media. To find out optimum quantity of media required for shoot proliferation, 1-5 multiple bud explants were incubated in each culture bottle. Explants density of 4/culture bottles was found best as it recorded higher total shoot production/l (291.94), shoot length (3.22 cm), number of leaves/shoot (2.81) and lower cost per shoot (Rs. 1.175). In vitro rooting was carried out with densities of 6, 8, 10 and 12 microshoots/culture bottle. The maximum response with regard to rooting had not yet been reached as there were no significant differences among the treatments. Incubation of 4 multiple bud explants and 12 microshoots per culture bottles is optimum for scaling-up of tissue culture production of banana cv. 'GRANDE NAINE'.

For an increasing number of plantlets, liquid culture methods have demonstrated a number of important advantages over conventional semi-solid micropropagation, including several fold increase in multiplication rate, reduction in medium cost and also space, energy and lobour requirements. These cost-saving advantages have been the driving force for increased attention to the use of liquid systems. Effects of liquid medium using different simple low cost culture containers on in vitro propagation of banana cv. 'GRAND NAINE' were investigated and compared with conventional solid medium. The treatments studied included: Growtech container with nylon wire mesh support; simple polypropylene container with cotton fibre support; simple polypropylene container with partial immersion, simple polypropylene container with full immersion and conventional baby jar bottle with agar gelled medium. Simple polypropylene container with cotton fibre support was found effective than that of agar-gelled medium. The plantlets produced were also sturdier and better quality.

Integrating targeted metabolic profiling with genetic diversity estimates is vital for selecting genetic stocks for breeding as well as mapping a biochemical trait. In Mucuna pruriens (L.) DC., copious amount of L-Dopa in seeds is viewed both as a boon and bane. Our objective of this work was to assess in conjunction both L-Dopa and genomic diversity in a selected set of germplasm to elucidate their relationship and identify parents for L-Dopa breeding/mapping. The findings revealed good genetic as well as metabolic (L-Dopa) diversity among the studied accessions. However, we could not establish direct relationship between these two as the marker data measured using AFLP and ISSR were not correlated with the seed L-Dopa contents. Based on the consensus information from both the data sets, seven parental combinations have been suggested. These findings are expected to pave way for genetic improvement as well as genetic mapping of L-Dopa trait besides integration of molecular markers in M. pruriens breeding programs.

Mass multiplication of non-Cavendish group of bananas has been limited due to non availability of reliable multiplication protocol and higher cost of production. The process of root induction and hardening are considered to be the most capital and labour intensive activities in micropropagation of any species. Carbon sources being one of the prime components governing the ex vitro survival of the plants need to be studied to maximize the success rate. Present is an attempt to study the effect of kind and concentration of carbon source on concurrent ex vitro rooting and hardening (CEVRH) in Ney Poovan banana. The results revealed that kind and concentration of carbon source present in the nutrient pool at the time of multiplication had a significant effect on the ex vitro performance of the plantlets. Better ex vitro rooting and hardening performance was exhibited by the shoots obtained from glucose (2 %) supplemented medium. Though rooting percentage was reduced in this treatment, considering the superior performance of the plantlets, it could be recommended to the commercial units for large-scale propagation of Ney Poovan banana plants. The concept of simultaneous rooting and hardening could be a boon for the varieties showing poor multiplication rate resulting in their higher cost of production.

Mucuna pruriens(L.) DC is a tropical legume cover crop with promising nutritional and agronomic potentials. It is also a key source of 3,4 dihydroxy-L-phenylalanine (L-Dopa) – a precursor of dopamine used in the treatment of Parkinson's disease. However, lack of well-characterized germplasm plus poor accessibility to genomic resources has hindered its breeding programs. Furthermore, the cause and effect of various biotic and abiotic stresses impacting yield is also little studied. Systematic collection and evaluation of Indian germplasm by our group revealed presence of a diverse gene pool in India that can support a variety of breeding needs. The stability of L-Dopa trait across environments examined through Genotype and environment (G × E) interaction studies, as well as feasibility check on barcoding and phylogenetic analyses based on karyotype and conserved nuclear and chloroplast genes showed promising outcome. Germplasm screening for select biotic abiotic stresses identified resilient genotypes. Advances in use of DNA markers for diversity analysis, linkage map development, tagging of genes/quantitative trait loci for qualitative and quantitative traits, and progress in genomics are presented.

Separated bud clumps of Silk Banana containing single and double buds were transferred on media containing six different cytokinins at three different levels and the proliferation capacity was determined. Proliferation, though occurred in single bud explants, the rate of multiplication was lower when compared with double bud explants, irrespective of the type of cytokinin used. Maximum shoot proliferation was observed in explants cultured on media supplemented with thidiazuron and 2-isopentenyl adenine (2-iP), and was significantly superior when combined with kinetin and BAP. Meta-topolin though reported to be highly efficient in improving multiplication in other banana varieties, no appreciable response was observed during present investigation. Use of NAA (2 mg l−1) was found to promote rooting process with superior root induction parameters and survival.

This paper reports new chromosomal information and earliest proof on efficacy of nrITS and cp-psbA-trnH gene sequences for barcoding and phylogenetic studies in Mucuna sp. First cytological evidence on M. sempervirens and M. bracteata revealed symmetrical karyotype in both the species. Meiotic anomalies evident from the formation of chromosomal laggards and bridges in M. gigantea and M. atropurpurea and unreduced pollens in M. bracteata suggest evolutionary events that might have shaped annual species in this genus. Molecular investigations using nrITS and cp-psbA-trnH sequences revealed them to be phylogenetically informative. Vis-a-vis individual genes, combined sequences of ITS and psbA-trnH sequences offered reliable data for species delineation. The results summarized here are expected to galvanize molecular taxonomic studies and open-up newer means for answering phylogenetic questions in this genus.

Mucuna pruriens L. (DC.) is a tropical legume cover crop with important agronomic and medicinal uses. Assessment of intra-specific variability for salt tolerance can aid its introduction in salinity affected areas. This paper reports first study on germplasm screening for variability in this trait among 35 accessions evaluated using nine indicative parameters. The experiments carried out under controlled condition revealed different levels of tolerance for the selected growth (3), physiological (2), and biochemical (2) characters - of which the first two provided reliable indicators for large-scale screening. Overlaying this data with diversity estimates from the AFLP analysis revealed 19 genetically divergent (> 90%) parental combinations that are useful for breeding as well as genetic mapping of this trait. Thus, this investigation opens-up new prospects for genetic improvement of M. pruriens to resourcefully recover them for coastal agriculture.

Factors concerning aseptic culture establishment and hardening were studied in detail in choicest Silk Banana. Effect of size of sucker (small, medium and large), carbon concentration (10, 20 and 30 g/l), season of initiation (wet and dry) and pre-treatments such as segmentation and incision to the explants were studied during initiation. Further, hardening related factors such as substrates used for primary and secondary hardening, nursery nutrition (source and frequency of application) and pre-treatments for ex vitro rooting were also studied. Results revealed that small suckers were most suited for initiations with the least contamination, maximum establishment and higher percentage of greening. Lower concentration of sucrose, though delayed greening, resulted in 100 % establishment of explants. Initiations performed during the drier period were completely free from the fungal contamination and showed less bacterial contamination than those performed during the rainy season. Segmentation of explant into four parts during first subculture supported maximum shoot proliferation by overcoming apical dominance. Coir pith was observed to be the most congenial substrate during primary hardening, whereas coir pith alone or sand: red earth: coir pith (1:1:1) supported superior performance of plantlets during secondary hardening. Single application of mono ammonium phosphate improved growth of plantlets during secondary hardening. Pre-treatment with mono ammonium phosphate gave the best response in terms of rooting and hardening of un-rooted micro-shoots. Thus, the discussed methodology could help the industries to take up commercial scale propagation of Silk Banana.

Ney Poovan is a group of elite mixed diploid bananas characterized by superior dessert quality and agronomic attributes. However, its commercial scale cultivation is largely jeopardized due to tall stature and longer crop duration than the commercial counterparts such as Cavendish bananas. Surveys were thus carried out in banana growing regions of Karnataka, India with the objective to identify short and precocious natural variants. The exhaustive surveys yielded a number of superior clones with near-idiotypic characteristics. Significant diversity existed among the 37 lines evaluated for traits such as plant stature, cropping cycle, yield contributing characters and productivity index. The discussed pragmatic approach involving exploration and utilization of the existing diversity was not only helpful in addressing the aforesaid problems but could also form the basis for rapid crop improvement in other long duration varieties of banana.

Abroma augusta has been used in folk Indian system of alternative medicine, for treating various conditions like diabetes mellitus, amenorrhea, nervous dysmenorrhea, antifertility and dermatitis. The objective of present study was to evaluate the phytochemical content, antioxidant activity, polyphenolic compounds and elemental analysis of the ethanol extract of leaves of A. augusta of Malaysian descent for the first time. Qualitative analysis of A. augusta leaf extract showed the presence of reducing sugars, alkaloids, tannins, phenols and flavonoids. Total phenolic and flavonoid content were found to be 15.76±0.16 mg/g gallic acid equivalent and 8.6±0.11 mg/g quercetin equivalent, respectively. Antioxidant activity showed that the IC50 value was 790±3.6 µg/ml and 367.6±16.9 mg/g ferrous sulfate equivalent by 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power assay, respectively. Presence of gallic acid, quercetin, ascorbic acid and essential elements such as calcium (Ca), copper (cu), iron (Fe) manganese (Mn), lead (Pb), zinc (Zn), nickel (Ni), magnesium (Mg) and sodium (Na) were determined by high performance liquid chromatography and atomic absorption spectroscopy, respectively. This study provided ample evidences that A. augusta is a rich source of polyphenolic compounds with good antioxidant activity. Thus, A. augusta may be a great natural source for the establishment of new drugs.

A number of factors are known to influence the aseptic culture multiplication, rooting and subsequent hardening in banana. Study of these factors would not only improve the in vitro response but also help in increasing the understanding of its basis. During present investigation, in vitro culture proliferation and root induction response in Silk banana as affected by different monochromatic lights (red, white, green and blue) was studied. In multiplication stage, cultures were grown on media with or without supplemental cytokinins. Results revealed that white light promoted shoot multiplication and growth on cytokinin rich media, when compared with other lights studied. Shoot multiplication was also improved in red light as compared to blue and green, but noticeable reduction in the quality of shoots was reported. Incubation of shoots under blue lights improved the quality of the shoots, and the regenerants were uniform in growth. White and blue lights also supported root induction and growth related parameters during in vitro root induction phase. Considering the growth response and uniformity of the cultures, blue light could be effectively used as an option in the slow growth culture in banana, however further investigations could help in optimizing the culture conditions.

Winged bean, Psophocarpus tetragonolobus (L.) DC., is analogous to soybean in yield and nutritional quality, proving a valuable alternative to soybean in tropical regions of the world. The presence of anti-nutritional factors and high costs associated with indeterminate plant habit have been major concerns in this crop. But occurrence of good genetic variability in germplasm collections offers precious resources for winged bean breeding. However, lack of germplasm characterization is hindering such efforts. From a genomic standpoint, winged bean has been little studied despite rapid advancement in legume genomics in the last decade. Exploiting modern genomics/breeding approaches for genetic resource characterization and the breeding of early maturing, high yielding, determinate varieties which are disease resistant and free of anti-nutritional factors along with developing consumer friendly value-added products of local significance are great challenges and opportunities in the future that would boost cultivation of winged bean in the tropics. We review past efforts and future prospects towards winged bean improvement.

A two-stage algorithm that detects and locates damages in thin walled structures using Lamb wave signals is proposed. Isotropic plate and shell structures with adhesively bonded piezoelectric transducers in circular and rectangular array patterns are considered. Lamb waves are generated and sensed by these transducers in pitch-catch mode, before and after making damages in the structure-under-test for baseline subtraction. In the damage identification process, first the correlation coefficient is determined using current and baseline signals. Further, the Trilateration method is adopted to locate the damage using parameters like Time-of-Flight and Group velocity from the damage-scattered Lamb wave signals.

Sensor data validation is a key module in any fault diagnosis system. A pattern recognition based algorithm is therefore proposed to validate the reliability of an arbitrarily distributed sensor network and its data. Single-frequency Lamb wave experiments are conducted on aircraft qualified aluminium plates, which have perfectly bonded and debonded Lead Zirconate Titanate patches along with structural damage in the form of holes. Sensor debondings are examined using sensor network data. Simple features like standard deviation, autocorrelation are extracted from Lamb wave signals and employed in the pattern recognition system that distinctly identifies the sensor debonding albeit the structural damage is present.