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EXPERIMENT: MINIMAL PROCESSING OF CAULIFLOWER (FREEZING PRESERVATION AND STEEPING PRESERVATION)

Materials and reagents

Material : Fresh cauliflower, glass jars, polythene pouches

Reagents: 15% sodium chloride

Greens and salad crops are grown for their foliage and are used since antiquity in soups, boiled, pickled or eaten raw and are recognized as important ingredients in the diet. Stephen Switzer, in Practical Kitchen Gardner (1727) identified 30-40 species as raw salads. Plants like Purslane, Burdock, Orache, Borage, Salad Burnet, Sea Kale, Dandelion, French Sorrel, Alexanders and many other plants are used as greens.
 
Greens and salads are very well represented in the garden works of John Randolph and Joseph Prentis in Williamsburg who  described that markets carried a wide selection of greens making available to the general public. But the salad greens were not mentioned in local diaries as often as common vegetables like cauliflowers, artichokes or melons, because they were used more as a garnish than as a main dish.
 
The popularity of individual varieties of greens changed over time. Many of the minor greens, like Purslane and Alexanders were common in the 17th century and before, but largely disappeared by the 18th century. Rocket, or Arugula, was listed by all authors in 16th and 17th century works but fell out of favor in England by the middle of  18th century.

New Technique of Food Preservation

1. High Pressure Processing (HPP)

High Pressure Processing (HPP) is a method of food processing where food is subjected to elevated pressures (up to 87,000 pounds per square inch or approximately 6,000 atmospheres), with or without the addition of heat, to achieve microbial inactivation or to alter the food attributes in order to achieve consumer-desired qualities. Pressure inactivates most vegetative bacteria at pressures above 60,000 pounds per square inch. HPP retains food quality, maintains natural freshness, and extends microbiological shelf life. The process is also known as high hydrostatic pressure processing (HHP) and ultra high-pressure processing (UHP).

Edaphology is the study of soil properties in relation to plant higher production.

Pedology refers to study of origin of soils in their natural environment, classification and description.

pH is the negative logarithm of the concentration of H+ ions in soil solution.

Soil profile is a vertical exposure of horizon sequence.

Soil texture is not changed by cultural management.

Cation exchange capacity (CEC) is defined as sum total of exchangeable cations that a soil can absorb.

Mites are small arthropods belonging to the sub-class Acari (also known as Acarina) and the class Arachnida. The scientific discipline devoted to the study of ticks and mites is called acarology. In soil ecosystems, mites are favored by high organic matter content and by moist conditions, wherein they actively engage in the fragmentation and mixing of organic matter (Nyle and Ray, 2009).

Mites are small arthropods which attack number of crops damaging different parts of the plants (leaves, buds, flowers and fruits) and due to short duration of life cycle and high fecundity, their population increases at a fast rate and when feeding in large numbers they become serious pest of many crops. Since last few years the menace of mites is on the increase in Indian sub-continent causing enormous losses. One of the probable reasons for it is attributed to excessive use of broad-spectrum pesticides, which have led to the development of resistance in mites. Further, owing to their deleterious effect on non target organisms, especially natural enemies of the mites in the ecosystem there is often a spurt in the population of mites which otherwise may be of minor pest category. Because of their small size, the infestation goes unnoticed in the beginning and by the time prominent symptoms appear a lot of damage has already been done.

FRUIT CROPS

In fruit crops, being perennial in nature, the infestation of mites not only affects the trees at a particular time but their overall vigour gets reduced which is reflected in reduction in production as well as poor quality of the fruit in the years to come. The identification characters, nature of damage and the symptoms must be well understood in order to manage the mite pests effectively. A number of mites are associated with various fruit crops and those infesting major fruit crops are discussed herewith.

ABSTRACT

The potato is one of the most important food crops both in developed as well as in developing countries. Developing countries today produce 37 per cent of world’s output of potatoes. Potato is an important food crop in India. Both area under potato cultivation and production has increased manifolds during past decades. The efforts are being made to improve potato quality and its post harvest life as well.

An experiment was conducted to isolate mitochondria from potato tubers and succinate dehydrogenase (SDH) assay and protein profiling were performed in the tissue. Three varieties namely, Kufri Bahar, Kufri Lauvkar and Kufri Jyoti were taken into consideration for the present investigation. Kufri Bahar showed the minimum values for SDH activity and Kufri Jyoti the maximum SDH activity. On the basis of SDH activity, the mitochondria in Kufri Jyoti were seemed to be more viable, functional and coupled as compared to Kufri Bahar and Kufri Lauvkar. This finding also suggested that the respiratory degradation of starch in Kufri Jyoti was higher as compared to Kufri Bahar and Kufri Lauvkar. Thus these result showed that the shelf life of Kufri Jyoti was less as compared to Kufri Bahar and Kufri Lauvkar. Protein profiling performed by SDS-PAGE was found to be similar in all the potato tubers.

Ingredient of 1kg mixed pickles: Cauliflower + diced carrot + turnip slice + vegetable pea each in equal amount of 1kg, salt 100g, ginger chopped 20g, onion chopped 50g, garlic chopped 10g, red chilli powder, black pepper, turmeric, cardamom large, aniseed powder, cumin, fenugreek powder each of 10g, clove headless 5 number and mustard 50g, vinegar 200 ml and mustard oil 450 ml.

1. MIXING AND DIVIDING

The main objective of mixing and dividing of seeds is to obtain the representative homogenous seed sample for analysis by reducing the submitted sample to the desired size of working sample.

2. TYPES OF MECHANICAL DIVIDERS

2.1. Boerner divider

The principle involved in mixing and dividing in gravitational force. It consists of a hopper, a cone and series of baffles directing the seeds into 2 spouts. The baffles are of equal size and equally spaced and every alternate one leading to one spout. They are arranged in circle and are directed inward. A valve at the base of the hopper retains the seeds in the hopper. When the valve is opened, the seeds fall by gravity over the cone where it is equally distributed and approximately equal quantity of seeds will be collected in each spout. A disadvantage of this divider is that it is difficult to check for cleanliness (Fig. 1).

Horticulture includes fruits, vegetables, floriculture, spices, tubers, plantation crops, medicinal and aromatic plants and mushrooms. The sector has established its importance in improving land use, promoting crop diversification, generating employment and above all providing nutritional security to the people. Even though India is the second largest producer of horticulture produces in the world, our per capita consumption of fruits and vegetables are very low.

6.1 Introduction

The process by which living beings give rise to the progeny of similar kind is called reproduction. Reproduction allows both multiplication and maintenance of a genotype/line/cultivar/species. So, the process of reproduction is also called propagation, and the plant part used for this purpose is called propagule. The way progeny originate is known as mode of reproduction (also called breeding system or reproductive system). The mode of reproduction of a crop determines its genetic composition which, in turn, is the deciding factor to develop suitable breeding methods. Knowledge of mode of reproduction is also essential for its artificial manipulation to breed improved types. The methods to be adopted for multiplication and maintenance of improved cultivars are also governed by the mode of reproduction. Especially in undertaking breeding investigations with new plants the nature of reproduction must be known before efficient breeding plans can be developed. The mode of reproduction has been well established for most of our important crop species.

6.2 Mode of Reproduction

Mode reproduction in crop plants may be sexual or asexual. In sexual reproduction (also called amphimixis), specialized reproductive cells called gametes are formed by the process of gametogenesis. Fusion of the male and female gametes leads to the development of an embryo and eventually the seed. In asexual reproduction, fusion of the male and female gametes does not occur, and new plants arise from unfertilized gametes (but not from zygote), or from specialized vegetative organs such as rhizome, tuber, bulb, corm, runner, sucker, stolon, bulbil etc., or by various artificial means of propagation such as rooting of stem and root cuttings, layering, grafting, gootee, etc., or tissue culturing.

The different modes of reproduction applied in vegetable crops are

Asexual

In this case the vegetative parts of the plants viz. rhizomes, corms, tubers, bulbs etc whole or part there off are utilized to produce new individuals. The typical examples are potato, sweetpotato, parwal, artichoke, colocasia, zinger, turmeric elephant foot yam, etc. There are some vegetative crops which can be reproduced through bcth vegetative part as well as seed e.g. asparagus.

The shift from vegetative to reproductive phase in plants is the result of multiple gene cascades in response to photoperiodic and temperature dependent pathways, gibberellic acid pathway, vernalization pathway and autonomous pathway. The environmental cues are initially detected in the leaves and the mRNA of the flowering signal integrator FT gene, moving to the shoot apical meristem, acts as a long-distance signal for floral meristem identity. At SAM, FT-FD protein complex, based on signals from above said pathways in association with the signals from age-dependent and miRNA pathways, leads to the activation of master regulator gene of flowering AP1. The activation of genes involved in ABCDE model of floral organ differentiation, based on the directions of various cadastral genes lead to the development of floral organs. Thus, the sequential action of floral meristem identity genes, floral organ developmental genes, floral meristem size and organ number genes, floral organ pattern genes and cadastral genes leads to the flower development. This chapter sums up the gene interactions happening in leaf and SAM, leading to the development of a complete flower.

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.

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.