eChapters

ABSTRACT

Black pepper (Piper nigrum L.), known as the ‘King of Spices’ is an important export- oriented spice crop, valued for its medicinal and condimental properties. A perfect protocol for the rapid in vitro multiplication of this plant is available. However, systemic bacterial contamination is the single major constraint in the large scale in vitro production of plantlets. Based on morphological and biochemical characters, this bacterium was identified as Beijerinckia indica It grows profusely on nitrogen-free Jensen’s agar and solubilizes CaCO in the medium by acid production. It is resistant to a range of antibiotics and produces indole acetic acid. The bacterium is slow growing and has pH optima of 5.5 and temperature optima of 27oC. It has both endophytic as well as epiphytic association with the plant, the colonization being more in the stem and petiole. A single plasmid of 4.0 kb size was isolated from the bacterium and characterized. Competent cells of E. coli DH5a, transformed with this plasmid survived on Jensen’s nitrogen free agar, indicating its ability to fix atmospheric nitrogen. We stipulate that the nif genes are located on the plasmid of the bacterium. Since endophytic bacteria are known to stimulate plant growth through antagonistic activity against pathogens, production of growth promoting substances and inducing systemic resistance in several other agricultural crop species, the symbiotic association between Bejerinckia indica and black pepper could be further exploited through integrated nutrient management for improved growth and yield of this spice crop.

ABSTRACT

An effort was made to characterize twelve ber genotypes using RAPD markers. Of the twenty random decamer primers tested, 17 generated polymorphic bands, while rest of the primers showed monomorphic bands. The primers that amplified all the 12 genotypes were OPC-20, OPD-1, OPD-3 and OPD-4. The size of amplified DNA fragments varied from 0.56-4.26 kilobase pair. In total, 109 bands were obtained, of which 85 bands were polymorphic, while 24 bands were monomorphic. For the cultivars tested between 2-9 bands were obtained for each primer with an average of 5.45 bands per primer. The highest number of bands (9) were generated by OPA-4 and OPD-3. With un-weighted group method using arithmetic mean (UPGMA) cluster analysis, the twelve ber genotypes fell into four major clusters. The pair wise dissimilarities of ber genotypes showed that genotypes G-9 and G-8 were close to each other. Maximum dissimilarity was observed between the genotypes G-8 and G-12.

ABSTRACT

The study was conducted to fingerprint and to analyze genetic diversity among 20 genotypes. of Psidium guajava and two species P. friedrichsthalianum and P. cattleianum using random amplified polymorphic DNA. Genomic DNA was isolated using modified CTAB method and polymerase chain reaction was carried out using standard protocols. In all 41 primers were used, 39 of which amplified 376 alleles with 347 polymorphic alleles. All the primers discriminated between two and more genotypes. Primers produced 2-16 alleles. The size of amplified DNA alleles ranged from 0.12-2.2 kilobase pairs. Polymorphic index content value was found to be maximum for primer OPB-12 (0.916). In the dendrogram all the 22 genotypes were grouped into two major clusters. Cluster 1 comprised of Spear Acid, Apple Colour and P. friedrichsthalianum, while Cluster 2 constituted rest of the 19 genotypes. Thus, RAPD markers detected a high level of polymorphism and can be used for breeding of improved guava varieties.

ABSTRACT

Piper colubrinum is a wild relative of the cultivated species of black pepper, Piper nigrum. The enzyme hydroxy methyl glutaryl Co A reductase which catalyses mevalonate synthesis, is the key enzyme in isoprenoid biosynthesis.This is the rate limiting step in the pathway which leads to the formation of sesquiterpene phytoalecins, a group of plant defense metabolites. Piper colubrinum is known to be tolerant to the dreaded disease called foot rot, incited by Phytophthora capsici. The hmgr gene is reported to confer resistance to fungal pathogens. Hence we made an attempt to isolate gene encoding this enzyme. cDNA was synthesised by reverse transcription from total RNA of P.colubrinum using oligo dt primers. Specific degenerate primers designed based on the conserved boxes among various plant species were used for amplifying hmgr gene from the cDNA. The 700 bp amplicon was cloned in pGEMT vector and sequenced with T7 primer. Multiple sequence alignment using clustal W 1.8 revealed homology of the cDNA fragment with hmgr genes in several other plant species. Maximum similarity was observed among P. colubrinum, Solanum xanthocarpum and Nicotiana tabacum. The cDNA library of P. colubrinum constructed in lTriplEx2 when screened with radiolabelled hmgr amplicon, yielded positive signals. Attempts are being made to isolate full length gene from these clones, which could be later used for imparting biotic stress tolerance to cultivated crop species.

ABSTRACT

Central Plantation Crops Research Institute at Kasaragod maintains largest collection of coconut germplasm accessions representing different geographical regions. So far, morphological and isozyme markers were employed for germplasm characterization. To overcome the difficulties associated with the morphological markers, DNA based molecular markers are presently employed for germplasm characterization. In the present study, Inter Simple Sequence Repeat (ISSR) markers are utilized to estimate the genetic diversity among South East Asian germplasm accessions. Nineteen ISSR primers were used to amplify 8 germplasm accessions (4 palms per accession referred as population). The PCR products were electrophoresed in 1.80 % agarose gels. Binary data were analyzed using the software POPGENE ver. 1.32. Dendrogram was constructed based on Nei’s unbiased measure of genetic distance. Nineteen ISSR primers detected a total of 85 polymorphic markers across 32 individuals belonging to eight populations. The average genetic distance among the eight populations ranged from 0.7908 to 0.9327 with a mean of 0.8540. Of the 28 pair wise comparisons the accessions Laguna Tall and Kongthienyong Tall (KTYT) showed the highest genetic identity (0.9327). The lowest identity (0.7908) was between San Roman Tall (SNRT) and Philippines Dalig Tall (PDLT). The Shannon’s index ranged from 0.1615 to 0.299. Diversity parameters viz. number of effective alleles, gene diversity, number of polymorphic markers were calculated for each population. The dendrogram constructed based on the genetic distance revealed clustering of Kongthienyong Tall (KTYT) and Laguna Tall (LAGT) while Philippines Dalig Tall (PDLT) was positioned separately. In the genetic improvement programmes the diverse accessions can be used in hybridization for increased heterosis.

ABSTRACT

Purine Nucleoside Phosphorylase (PNP) is an enzyme that functions in the purine salvage pathway by catalyzing the phosphorolysis of purine nucleoside thereby releasing the purine bases and phosphorylated sugar. Interest in PNP as a drug target arises from its role in T-cell proliferation and T-cell mediated autoimmune diseases. Recently, we have isolated the compound, coixol, from the plant Scoparia dulcis L. and its three-dimensional structure has been elucidated. As the structure of the coixol mimics the structure of PNP inhibitors, we have undertaken the molecular modeling studies of this compound with Human PNP, as a screening test for further in vivo studies. Generally PNP inhibitors have been synthesized with a ribose sugar moiety attached to them. As the plant Scoparia dulcis L. contains glucose and rhamnose (six membered ring), these sugar moieties are also included along with ribose in the presen study. In order to understand the binding mode and interactions of the isolated compound attached with different sugar groups, we have carried out the docking studies with Human PNP. The interactions between the ligand molecules and active site residues of Human PNP are similar to those of solved complexes and the energy values are also comparable, which clearly indicate that these ligands may act as inhibitors.

4.1 Introduction

Many important traits such as yield, quality and some forms of disease resistance are controlled by many genes and are known as quantitative traits or characters (also called ‘metric’,‘polygenic,’ ‘multifactorial’ or ‘complex’ traits). The regions within genomes that contain genes associated with a particular quantitative trait are known as quantitative trait loci (QTLs). The identification of QTLs based only on conventional phenotypic evaluation is not possible. A major breakthrough in the characterization of quantitative traits that created opportunities to select for QTLs was initiated by the development of DNA (also called molecular) markers in the 1980s.

One of the main uses of DNA markers in agri-horticultural research has been in the construction of linkage maps for diverse crop species. Linkage maps have been utilised for identifying chromosomal regions that contain genes controlling simple traits (controlled by a single gene) and quantitative traits using QTL analysis. The process of constructing linkage maps and conducting QTL analysis–to identify genomic regions associated with traits–is known as QTL mapping (also called ‘genetic,’ ‘gene’ or ‘genome’ mapping). DNA markers that are tightly linked to agronomically important genes (called gene ‘tagging’) may be used as molecular tools for marker-assisted selection (MAS) in plant breeding. MAS involves using the presence/absence of a marker as a substitute for or to assist in phenotypic selection, in a way which may make it more efficient, effective, reliable and cost-effective compared to the more conventional plant breeding methods. The use of DNA markers in plant (and animal) breeding has opened a new realm in agriculture and horticulture called ‘molecular breeding’.

5.1 Introduction

The development of quantitative trait loci (QTL) mapping methods to identify genes or QTLs controlling quantitative traits was a landmark achievement in plant genetics research in the late 1980s. Since then literally thousands of research papers have reported the identification of genes or QTLs for important traits across a diverse range of plant species. This wealth of genetic information was built on the foundation of decades of research in crop molecular genetics and genomics.

The selection and enrichment of QTLs within breeding material was the inevitable next step from QTL discovery to application, and there have been numerous reports of successful tracking of genes and QTLs within breeding programmes. DNA (or molecular) markers have enabled selection of major genes or QTLs for critical or important traits in a process called marker-assisted selection (MAS), which has revolutionized plant breeding. DNA markers are used as tools by breeders to improve the accuracy or efficiency of selection as well cost and time efficiency. Apart from MAS, DNA markers have numerous applications including DNA fingerprinting, genetic diversity analysis and parental characterization.

Recent developments in genotyping platforms and systems to implement molecular breeding schemes offer new tools for modern plant breeders. Single nucleotide polymorphism (SNP) markers are biallelic, co-dominant markers which are abundant in the genome. Insertion-deletion (Indel) markers are also prevalent and can be screened using high-throughput genotyping platforms. These platforms are cost-efficient, can handle large sample sizes and provide fast data turn-around time. The availability of genome sequences and genomic resources continues to provide a wealth of SNP and Indel markers which will undoubtedly be the marker type of choice for decades to come.

The availability of high-throughput SNP platforms in conjunction with advances in computational methods has also led to the molecular dissection of traits using genome-wide association studies (GWASs) across diversity panels and the development of genomics-based molecular breeding strategies. Association mapping (AM) has now emerged as a standard method for gene and QTL discovery for major crops.

ABSTRACT

Genetic improvement of crop plants through conventional plant breeding has made tremendous contributions to the breakthrough in the global agricultural production. Recently, an array tools and techniques in the field of molecular biology has become available for supplementing the conventional genetic approaches. Consequently, new integrated approaches are being designed. One of the approaches employs molecular markers for genome mapping, gene tagging and marker assisted selection (MAS). With the complete sequencing of whole plant-genomes and a large number of random cDNAs in many different crop species, newer opportunities are emerging. This presentation is an attempt to briefly describe the current applications of molecular markers and to highlight their future prospects.

Molecular markers

Molecular markers are heritable differences in nucleotide sequences of DNA at corresponding position on homologous chromosomes of two different individuals, which follow a simple Mendelian pattern of inheritance. These differences are detected employing two basic techniques: (a) Southern blot hybridization and (b) Polymerase chain reaction (PCR). Restriction Fragment Length Polymorphism (RFLP) is the first molecular marker system to be conceived and developed. It is based on the southern blot technique. Markers such as random amplified polymorphic DNA (RAPD), sequence tagged site (STS) and amplified fragment length polymorphism (AFLP) are generated by enzymatic amplification of DNA by extension of oligo nucleotide primers and therefore, are based on PCR. Single/simple nucleotide polymorphism (SNP) markers are based on DNA sequence differences as revealed by sequencing and assayed by various techniques.

The harmony between human beings and plants is one of the evergreen reasons that maintains and supports life on earth. This fact clearly explains why any hazard to the life of plants prominently affects man. One important feature distinguishing plants from other complex multicellular organisms is that plants are sessile and thus have to endure environmental challenges (Zhu, 2001).

Crop productivity is limited by stress factors. The stresses which pose major threats to survival of plants belong to two categories- abiotic and biotic stress. Drought, salinity, high or low temperatures, light, deficient or excess nutrients, heavy metals, pollutants etc., either individually or in combination causes abiotic stresses. Biotic stress refers to any stress provided by living organisms, be it unicellular or multicellular. Plants facing a variety of biotic and abiotic stresses are able to protect themselves by means of tolerance mechanisms which result from changes at the molecular level. They are often confronted by a multitude of stresses in their natural environment. To overcome this, plants have evolved various defence strategies, which involve comprehensive reprogramming of the cellular metabolism.

Use of morphological markers has continued till today for characterization of several crops including horticultural crops with the Mendel’s principles of inheritance by following visible traits in the progenies of sexual crosses. Genetic markers play an essential role  in the study of variability and diversity, in the construction of linkage maps, and in the diagnosis of individuals or lines carrying certain linked genes. Within this context, the limitations of morphological markers became quickly apparent. They tend to be restricted to relatively a few traits, display a low degree of polymorphism, are often environmentally variable in their manifestation, and can depend on the expression of several unlinked genes. Furthermore, some may affect plant viability or seed set, distorting gene frequencies in the progeny. Morphological markers were largely supplemented by biochemical markers, particularly isoenzymes that could be easily scored by electrophoresis (Ganapathy and Scandalios 1973; Tanksley 1983). The limitations of isoenzmyes as markers, in particular both the limited number of polymorphic enzymes that can be conveniently stained and the environmental effects on expression pattern, were apparent already twenty years ago (Tanksley 1983).

ABSTRACT

Mushrooms are in use for centuries in traditional system of medicines, and have importance in greater Chinese and western pharmacopeia. Morchella species are well known across the globe as a popular and prized edible fungi and unique culinary saprophytes. They have a long history of usage in the formulation of different traditional medicine for centuries due to their anti- oxidant, anti-inflammatory, anti-cancerous and immuno-stimulatory properties. Inspite of high demand and day-by-day increasing importance, cultivation of M. esculenta Dill.ex Pers and other morels are limited, however, there is a report that some species of Morchella are successfully cultivated in China. Phytochemical studies reveals that polysaccharide groups, phenolic compounds, tocopherols, ascorbic acid and vitamin D are the most active molecules present in morels. In addition to these compounds, morels are also rich in carbohydrates, amino acids, fatty acids, organic acids and several kinds of macro-and micronutrients. Literature revealed that no data on reproductive biology of M. esculenta are available till date. Future investigation is required to study the life cycle and the ecological association of different morels to high altitude regions, and causes of their association with coniferous and broad leaved trees such as Cedrus deodara, Pinus gerardiana, Picea smithiana, Quercus and Castanopsis species. There is an urgent need to explore all traditional knowledge associated with morels, phytochemistrys and associated pharmological studies of major compounds, reproductive cycle and their basic biology for future conservation of this precious mushrooms for man-kind.

Objective

1. To know the morphology of different spices and condiments.

Materials: The crop of spices and condiments available at Horticulture research farm

Method of observation: Identification of various spices and condiments plants by carefully observing the root, stem, leaves, inflorescence, flower, fruit and seeds of the plants.

General

1. Habitat: A habitat is an ecological or environmental area that is inhabited by a particular species of plant. The term typically refers to the zone in which the plant lives and where it can find food, shelter, protection and mates for reproduction It is the natural home of a plant. Each habitat has its own particular type of climate like:
   1. Tropical Spices: These are grown at 1800 m - 3500 m height from ground level eg. clove, nutmeg, cinnamon, konkam, galangal, small cardamom, vanilla, black pepper, ginger, turmeric.
   2. Subtropical Spices: These are grown at 300 m - 900 m height from ground level eg. cumin, dill, fennel, coriander, fenugreek, onion, garlic
   3. Temperate Spices: These are grown at 900 m - 1800 m height from ground level eg. saffron, asafetida, caraway seed, celery seed, savoy, caper, balm, origanum, calamus, thyme etc.

A. General Morphology

2.1 The Root

It is the organ of a plant that typically lies below the surface of the soil.The root is best defined as the non-leaf, non-nodes bearing parts of the plant’s body. However, important internal structural differences between stems and roots exist. Root spices are, rather surprisingly, rare. Some popular examples of spices having roots are: Apium graveolens (Celery), Armoracia rusticana (Horse radish), Coriandrum sativum (Coriander), Ferula asafoetida (Asafetida), Glycyrrhiza glabra (Licorice), Levisticum officinale (Lovage), (Petroselinum crispum (Parsley), etc. All of the mentioned plants have aromatic roots.Roots of gingiberaceae are adventitious and storage roots arise from among the nodes of these scales.

Purpose: In propagation of fruit plants by any vegetative methods such as cuttings, budding and in to the selection of ‘mother plants” and “bud-wood”. Use of bud-wood or any other propagation material from high yielding, true to-type, disease free trees (mother plant) will ensure uniform behaviour of trees in the orchard. If possible, propagation material from a single source is used.

Bud-wood used for budding purpose from high yielding, true-to-type and disease free trees certified for the above character by a certifying agency is referred as ‘certified bud’

Procedure: By adopting the flow sheet given below, clean scion from healthy, productive plants, can be selected for vegetative propagation.

ABSTRACT

Green revolution provided sufficient amount of foods but the way resources were utilized causes the degradation of natural resources in various aspect. The adverse effect on the ecological system can be visualized in the form of various diseases in human and loss of biodiversity. The population burst is the root cause of imbalanced ecological system because agricultural land decreases drastically. Therefore we must aim to develop and improve the agri- economic growth of farmers by introducing elite variety of Mucuna pruriens (L.) DC. M. pruriens, a member of Fabaceae family, is an adaptogen and known for its tonifying, strengthening and all around beneficial properties from every part of the plant. M. pruriens has range of medicinal applications, because of unusual amino-acid L-DOPA (L3, 4dihydroxyphenylalanine) a precursor of neurotransmitter dopamine (Anti Parkinson’s) and involved in various secondary metabolite pathways. It acts like aphrodisiac, anti-snake venom, anti-depressant, antidiabetic, anti-microbial. It has a nutritional quality comparable to soyabeans. M. pruriens exhibits a tolerance for various kinds of environmental stresses such as drought, low soil fertility, and high soil acidity. M. pruriens suppresses weeds through indeterminate growth and large leaves reduce the amount of light for weeds. It shows allelopathy and effective in lowering nematodes. M. pruriens is used as forage, fallow, green manure prevents the soil erosion. It has a longer time span to be used in rotations for management of various pathogens.

Mulching

It means covering of soil surface by some organic or inorganic materials for conserving the soil moisture besides covering on the soil moisture several other advantage of mulching. The materials which are used in mulching called mulch.

1. Introduction

Lichens are the most fascinating and widely distributed organisms on earth. The lichens are unique in having two microorganism in a single plant- a phycobiont (alga) and a mycobiont (fungus) forming a thallus that does not resemble either symbionts in the free living (non- lichenized) state. By virtue of the peculiar structure and physiology, lichens have high tolerance of drought and cold and are able to grow in the diverse geographical regions from icy expanses to tropical and subtropical parts and from drier, hot deserts to moist humid climate. Lichens grow on any substratum that provides a convenient foot hold to them. This may be soil (terricolous), humus (humicolous), stones, rocks, brick (saxicolous), lime plaster (calcicolous), leaves (folicolous), tree trunk (corticolous), decaying wood (lignicolous) and other man made substratum like iron pipes, asbestos sheet and glass panes. Sometimes lichens also grow on some insects and animals. Lichens which are bigger in size and shape can be easily recognized as leaf like (foliose) and thread like (fruticose) (commonly called macrolichens), while those which forming a crust over the substratum and quite smaller in size are categorized under microlichens.

Apart from altitudinal variation, the vegetation and forest types of higher plants also play an important role in determining the type of lichen flora of the region. Based on the forest types six lichen vegetation zones are known in India such as: Moist tropical evergreen forest, Cold deserts in the Himalayas, South Peninsular region, Mid Eastern Indian & Peninsular Plateau, Dry and arid regions and Indo-gangetic plains of central India, Coastal regions of India and Andaman & Nicobar Islands. The cold deserts in the Himalayas exhibit some unique group of lichens having restricted distribution only in such habitats.

1. Introduction

A combination of art and science had been used for a longer but due to the exponential increase in human population and reduction in operational land holdings its practices became narrow. Nowadays, gardening has gained much popularity among people, as the Covid-19 pandemic has forced them to lock themselves in their houses. These days Mass population is involved in gardening for growing their own food, resulting in a more personal approach to more economical, better-tasting, and healthier products (Pawelek et al., 2009). Gardens have grown increasingly significant for producing nutrient-dense food, protecting biodiversity, and conducting biological and ecological research and education. Biological communities, which are interacting groups of numerous species in the same place, can also be found in gardens. Pollinators and other visitors to flowers eat nectar and pollen from flowers, and some may use floral volatile oils, lipids, or resins for their food, shelter, and mating locations (Simpson and Neff, 1983).

1. Tea require months from plantation to reach plucking is:
    (a)    18-20     (b)    22-24     
    (c)    36-40     (d)    30-34
2. Fruit of coffee is:
    (a)    Pome     (b)    Drupe     
    (c)    Berry     (d)    Aggregate