eChapters

ABSTRACT

The present experiment was conducted in order to develop a protocol for rapid in vitro propagation of pomegranate Cv. Mridula. Shoot tip and nodal segment explants selected from mature plant were cultured in MS medium supplemented with NAA and BAP in different concentration and combinations. To control phenolic browning, sub- culturing of cultures was under taken at an interval of first and third day after inoculation. The MS medium supplemented with NAA 0.4 mg/l + BAP 1.0 mg/l showed highest percentage of shoot differentiation with 77.77 per cent and 81.25 per cent response from shoot tip and nodal segment explant respectively. In the same media, earlier shoot initiation as well as more number of multiple shoots/culture were obtained. The shoots when elongated up to 2.5 - 3.0 cm length were transferred for rooting in the ½ strength MS media supplemented with auxins. There was no significant difference for root induction among the type of auxin used either NAA, IBA or both in combination. The concentration of auxins 0.5 mg/l was found to be optimum. Rooted plantlets after hardening in green house gave 49 per cent survival.

ABSTRACT

Direct shoot organogenesis from several explant types excised from in vitro grown plants of local elite tomato cv. PKM1 was studied in response to zeatin, BAP, IAA and NAA. Cotyledonary leaves were found to be the most responsive explants. High shoot bud induction rate (>25 shoot buds/cotyledonary explant) was obtained in the presence of 2 mg/l zeatin. The organogenic calli were subcultured onto the same shoot bud induction medium for shoot development. Among different growth regulators tested, zeatin @ 2 mg/ l induced more number of shoots per explant compared to BAP, IAA and NAA combinations. Rooting was efficiently induced on half strength MS basal medium supplemented with 0.5 mg/l IAA. The effects of various growth hormones on tomato regeneration on rooting were discussed.

ABSTRACT

Vanilla (Vanilla planifolia Andrews) is a high value spice crop having immense potential for cultivation in India as a source for natural vanillin. Though the crop was introduced way back in 1835, its cultivation gained momentum only in the recent past due to various reasons. Lack of sufficient good quality planting materials is one of the constraints for expanding the area under the crop. Conventionally vanilla is propagated by vine cuttings, but this method is inadequate to have large number of planting materials in a short span of time. So, micropropagation was attempted and proved to be highly successful. In the present study, performance of vanilla plants raised from tissue culture plantlets and vegetative cuttings was assessed on large-scale in planters’ field covering a total area of 111 ha in Kerala(68ha), Karnataka(28ha) and Tamilnadu(15ha) with the financial assistance of the Department of Biotechnology, New Delhi under the project entitled “Tissue culture Vanilla : Product Plan“. Disease free elite accessions of vanilla identified by the Indian Cardamom Research Institute (Spices Board), Myladumpara from its germplasm repository were used as mother plant source for tissue culture multiplication and also for raising the nursery for producing vegetative cuttings. The field planting for the demonstration plots was carried out during 1996-1999 on a cluster approach basis having 400 plants in each unit or plot of 0.25 ha. Accordingly a total of 444 evaluation plots were laid out under the project covering the aforesaid three states. Out of the 400 plants in a plot, 80% were nursery hardened grown up tissue culture plants and the balance( 20% )vegetative cuttings of comparable length. Observations on growth and yield attributes such as vine length, number of leaves per vine, internodal length, number of beans per vine, bean size, yield etc. revealed that performance of tissue culture plants is on par with that of conventional plants raised from vegetative cuttings of comparable length. It is also observed that if good management practices are adopted, tissue culture plants perform better at the full bearing stage of the plant. This proves that tissue culture plants of vanilla can be popularized as a cost effective and faster source of planting materials compared to conventional vegetative cuttings. As the demonstration plots were distributed under varied agroclimatic situations, the influence of different weather parameters on yield was also ascertained. Further, the project could convince the farmers about the comparable performance of tissue culture plants and that is quite evident from the ever increasing request for tissue culture vanilla plants received by the Spices Board.

ABSTRACT

Dissected shoot tips from healthy suckers of banana var. Meitei Hei (local variety) were inoculated on Murashige and Skoog (MS) medium supplemented with different concentrations and combinations of plant growth regulators viz., NAA and BAP. After 15 days of incubation 50% of the shoot tips turned green in the medium with 5.0 mgl^-1 BAP. A maximum of 85.7% of the explants produced phenolic exudates in MS + 5.0 mgl^-1 BAP. After one month the explants were subcultured in fresh medium with the respective concentrations and combinations of plant growth regulators. After 75 days of incubation an average of 2.20 microshoots were induced in 78.57% of the explants in MS + 5.0 mgl^-1 BAP. The regeneration of shoots, leaves and roots was more proportionate in MS + 0.1 mgl^-l NAA + 0.5 mgl^-1 BAP. Under the treatment the microshoots had an average height of 1.19 cm with 4.13 leaves and 2.40 roots. The multiple microshoots were separated and subcultured on MS + 0.1 mgl^-l NAA + 0.5 mgl^-1 BAP for proper development. After 120 days the completely regenerated plantlets were hardened under green house environment.

ABSTRACT

Vanilla planifolia Andrews - the high value, exotic spice crop has recently gained wide acceptance in the southern and northeastern states of the country. Being an orchid, germination of naked embryo is limited and this favours genetic uniformity. An attempt was made to induce genetic variability in Vanilla through biotechnology tools for its exploitation in crop improvement programmes. In vitro embryo culture and mutagenesis were applied for the purpose. Plantlets were multiplied, hardened, planted out and evaluated for morphological, biochemical and molecular markers. Great interclonal variability was observed in the in vitro derived plantlets. The intraclonal variability was very low in tissue culture derived regenerants. Isozyme and RAPD assay confirmed genotypic variation. Six superior clones were identified and distributed to farmers for further evaluation.

ABSTRACT

Astudy was undertaken to evaluate the performance of tissue culture derived plants vis a vis open pollinated seedlings of cardamom (Elettaria cardamomum Maton). A total of 102.5 ha (units) covering 50 ha in Kerala, 37.5 ha in Karnataka and 15 ha in Tamil Nadu was selected for the present study out of which each demonstration plot (unit) had an area of one hectare in which 80% of the plants are tissue cultured and 20% are open pollinated. Elite cardamom clones were subjected to in vitro multiplication and their respective open pollinated seedlings were compared. The planting was initiated in 1989 and completed with 1991 in all the zones identified. Plant growth characters such as number of tillers, number of bearing tillers and panicles per clump were recorded and compared. The yield was recorded in 1993-94 and 94-95 seasons after its stabilisation. Results indicated that tissue culture plants performed better compared to open pollinated seedlings with regard to growth attributes and yield irrespective of the seasons and zones. In Kerala region tissue culture plants exhibited a yield increase of 24.3 and 36% over open pollinated seedlings for the 1989 and 1990 plantings respectively. Similar trend was observed in Tamil Nadu for 1989 and 1990 planting where the percentage increase in yield became 130 and 21 respectively. In Kerala, the yield performance of tissue culture plants and open pollinated seedlings was on par during 1990 planting but in the subsequent year (1991) tissue culture plants showed 24% increase in yield compared to their respective open pollinated ones. Further, the study enabled to identify cardamom clones suited to in various zones of the cardamom tract. Accordingly 14 clones with a yield potential of over 750 kg/ha under moderate management were identified and this indicated that cardamom clones are highly location specific in their performance.

ABSTRACT

Recognizing the need to apply plant tissue culture tools for generating planting materials of important spice crops especially vanilla, the Spices Board started Biotech Production Unit at its head quarters building at Kochi with an annual production potential of 8 lakhs plantlets. Complete tissue culture protocols were developed and scaled up for large scale production of vanilla and other spices viz. large cardamom, small cardamom and tree spices. The laboratory is equipped with all modern facilities and is established in an area of about 2000 sft. Department of Biotechnology, Govt. of India also participated in the venture by sanctioning a project entitled “Regional centre for large scale production of tissue culture plantlets of vanilla and other spices” with a financial out lay of Rs 95 lakhs equally shared by DBT, New Delhi and Spices Board, Cochin.

At present there is a stock of over 3.00 lakh vanilla cultures in the lab and already 1.25 lakh plant lets were sent for hardening. The Spices Board, in coll aboration with “Kudumbashree”, a poverty eradication mission of Govt. of Kerala, extend short term training in tissue culture techniques to undergraduates from ‘Below Poverty Line’ (BPL) families and engage them as long term trainees in the Biotech Production Unit. The Board also coordinates and extends support to Kudumbashree members for, establishing and maintaining hardening facilities for TC plantlets thus providing means for empowering women from BPL families.

ABSTRACT

Jasmine is one of the economically most important flower crops cultivated for its fragrant flowers and valuable essential oil. In vitro studies to explore the possibility of regeneration of plantlets from different explants and to undertake biochemical analysis to detect the flavour compounds if present in the in vitro cultures were taken up with local varieties of Jasminum grandiflorum.

Among the different explants tried, leaf bits were found ideal for callus induction, followed by petals and shoot tips. MS medium with 2, 4-D at 1.25 ppm was the suitable medium for callus induction in leaf explants. Miller medium with NAA at 1.25 ppm and BAP at 1.25 ppm was the suitable medium for callus induction in petal explants collected from 18 days old buds of local varieties of Jasminum grandiflorum. Among the different media combinations tried, MS medium supplemented with 0.2 ppm NAA and 0.3 ppm GA₂ is the best medium for callus induction in shoot apex explants of 10mm size. Direct regeneration of plants was obtained in 10 per cent of shoot apex explants cultured in MS medium supplemented with 0.2 ppm GA₁ and 3 ppm BAP in 60 days. A maximum of 95 per cent embryogenicity is induced in leaf callus transferred to MS basal medium supplemented with 1.5 per cent sucrose from MS medium with 2, 4-D at 1.0 ppm.

The peroxidase assay indicated that embryogenic calli had six isoperoxidases while the non-embryogenic had only two. Biochemical analysis of the callus samples showed high Phenylalanine ammonia lyase and phenol indicating the initiation of phenolic pathway, which branches out and ultimately leads to the synthesis of flavour compounds in callus.

ABSTRACT

Donor-recipient protoplast fusion vis-à-vis cybridization is an effective technique to transfer plasmon-coded traits in cultivated tetraploid (2n=4x=48) potato (Solanum tuberosum L.) from its diploid (2n=2x=24) cross-incompatible wild relatives. However, the method, although attractive, is difficult in terms of not only inactivation of nuclear and plasmonic genomes of the participating donor and recipient protoplasts, but also post- fusion culture and regeneration of putative cybrids. Here, we report an improved method for donor-recipient protoplast fusion and subsequent post-fusion culture and regeneration of electrofused protoplasts in potato. In the present experiment, Solanum verrucosum Schlechtd. (2n=2x=24) accessions CPC 1339 (CGN No. 17774) and HAW 2246 (CGN No. 17766) containing sensitive [Tr^s] plasmon for tetrad-type cytoplasmic male sterility were used as donors and S. tuberosum subsp. tuberosum cvs Kufri Ashoka, Kufri Chipsona-1 and Professor Broekema as recipients. For nuclear inactivation, the in vitro-cultured donor plants were exposed to 1000 Gy of unfiltered γ-rays before protoplast preparation using a revised protoplast isolation medium (PIM) containing 2.0 % Cellulase ‘Onozuka’ RS and 0.25 % Macerozyme R-10. The recipient protoplasts were treated with antimetabolite iodoacetate (1.0 mM ) for 45 min at 10 °C for chondriome inactivation. The protoplasts were aligned in an amplitude of 300 Vcm^-1 for 0.5-1.0 s before being electrofused by one DC pulse of 600-800 Vcm^-1 for 40 μs using a Cell Electrofusion Processor FPH 01001 (Bioelectronics Corporation, Troy, Michigan). The fused protoplasts were immobilized in alginate-plates, and cultured on modified VKM medium containing 0.3 M glucose at about 400 mOsmol (pH 5.6). After 8-10 weeks, the developing protocalluses were dissociated from alginate-plates and cultured for regeneration on MS medium supplemented with varying concentrations of zeatin/ zeatin riboside and gibberellic acid. The protocalluses derived from electrofusion between donor S. verrucosum accession CPC 1339 and recipient S. tuberosum cv. Kufri Chipsona-1 could be successfully regenerated into plantlets. Morphological as well as molecular-genetic characterization of regenerated microplants, both for nuclear and chondriome genomes, confirmed the putative cybridity as well as established the extent and pattern of mitochondrial recombination following donor-recipient protoplast fusion. The results have been discussed in relation to donor-recipient protoplast fusion approach and its potential application in potato genetic improvement.

ABSTRACT

The investigation was carried out to develop protocol for micropropagation of acid lime (Citrus aurantifolia S) var. Sai-Sharbati. Shoot tip and nodal segment explants were obtained from axenically grown seedlings having 21 to 30 days age. Direct regeneration of shoots, roots and whole plant without intervention of callus was obtained from both the explants on MS basal media. In both the explants 100 per cent shoot proliferation was induced in nutrient medium MS + BA 0.25 mg/l + ME 200 mg/l. The shoot proliferation rate was more (5.0) in nodal segment as compare to the shoot tip explant (4.33). Regenerated shoots of more than 2.5 cm length with minimum of 4 leaves were transferred for rooting. Half strength MS medium supplemented with IBA 1.0 mg/l was best for root induction and root initiation within 15.66 days. More than 75 per cent plantlets were survived after hardening period of four weeks.

ABSTRACT

Immature seeds of Garcinia indica were excised from the green fruits and cultured on Woody Plant Medium (WPM) with a combination of auxins and cytokinins. Somatic embryos were obtained on the media supplemented with BAP (0.5-5.0 mg/l) alone or in combination with NAA 90.5 mg/l) with 80 per cent frequency within a period of 2-3 weeks. Subculture of primary embryos on maturation medium containing BAP (3.0 mg/l) supplemented with IAA (0.5-1.0 mg/l) and / or Kinetin (1.0 mg/l) gave rise to clusters of secondary somatic embryos. In the subsequent subculture on hormone free half strength WPM the embryo clusters germinated with repetitive secondary embryogenesis. About 70 per cent somatic embryos germinated into complete plantlets, which were successfully transferred to the green house conditions.

ABSTRACT

The totipotency of triploid endosperm tissue is exploited in many vegetatively propagated crops. Hevea brasiliensis, the most important commercial source of natural rubber, is a highly heterozygous perennial tree with a long breeding cycle. Conventional method of triploid production by crossing a diploid with an artificially induced tetraploid is a lengthy and laborious process. Hence in vitro regeneration of plants from endosperm tissue provides an easy and direct approach for the production of large number of triploids. Hevea fruits at different developmental stages were collected and sterilized using 0.1% HgCl₂ for 15 minutes. Seeds were dissected out and the embryos and inner integuments were removed. Endosperm is cut into small pieces and cultured over MS medium supplemented with various levels of sucrose, phytagel and growth regulators viz BA, Kin thidiazuron, 2,4-D, IBA, NAA, zeatin & GA. Organic supplements viz. yeast extract, casein hydrolysate, coconut milk and banana powder were used for callus and embryo induction. Optimum callus induction was obtained in media supplemented with 2,4-D (2.0 mg ^-1) and Kinetin (3.0 mg^-1). On further subculture of the primary calli to medium containing zeatin (1.0 mg ^-1), embryogenic calli could be obtained. Embryos were induced in MS medium supplemented with ABA (0.3 mg ^-1) , Kin (0.3 mg ^-1) and GA (0.5 mg ^-1). Maturation, germination and bipolar differentiation of the embryos were achieved in MS medium devoid of growth regulators. Root tips from the germinating embryos were subjected to cytological analysis and found to be triploids (3n=54). Regeneration from Hevea endosperm is being reported for the first time. The results indicates that like many other crops, Hevea endosperm responds well under in vitro conditions and endosperm culture could be utilized as a viable technique for triploid plant production.

ABSTRACT

Microbial contamination is perceived as the most serious threat faced by plant tissue culture research laboratories and commercial production units. A culture is often viewed as contaminated when obvious microbial growth incited by fungi, yeast or bacteria is noticed on the culture medium. On the other hand, there can be situations when microbes may be present in a covert or latent form with serious side effects on the cultures. The present investigations were taken up with the objectives of elucidating the cause of poor growth, lack of regeneration response or modification of rooting observed with visibly clean cultures of different horticultural crops. Apparently clean cultures of grape, banana, watermelon, eggplant, gerbera and chrysanthemum of recent origin or after long-term in vitro culturing were used in this study. Indexing the medium of such cultures using fungal/ yeast and bacteriological media brought out the covert association of one or more bacterial types with varying proportions of incidence in such cultures. Indexing of tissue revealed bacterial presence in different parts of in vitro plantlets. In some instances, bacteria showed endophytic colonization while being not detectable in the tissue culture medium subsequent to a disinfection or antibiotic treatment. Such bacterial association appeared to be the cause of in vitro decline observed with long-term micropropagated cultures, lack of reproducibility of tissue culture protocols, failure of in vitro rooting etc. besides being a threat to in vitro gene banks and germplasm exchange.

ABSTRACT

Techniques could be standardized for the induction, initiation, maturation and germination of somatic embryoids from the nucellar tissue isolated from 30-45 day old fruits of mono embryonic mango variety Neelum and poly embryonic variety Vellari Manga. The treatment half strength Murashige and Skoog basal medium containing 2,4-D 5.0 mgl^-1, GA3 5.0 mgl^-1, glutamine 400 mgl^-1, coconut water 200 mll^-1, activated charcoal 500 mgl^-1, sucrose 60 gl^-1and agar gl^-1was found to be the best in induction of embryogenic callus. The treatment 2,4-D 4.0 mgl^-1 + BA 1.0 mgl^-1+ GA3 5.0 mgl^-1in half strength MS basal medium supplemented with glutamine 400 mgl^-1, casein hydrolysate 500 mgl^-1, sucrose 60.0 gl^-1, coconut water 200 mll^-1and agar 6.0 gl^-1was the best in initiating somatic embryos from the induced nucellus of the three varieties. In the variety Neelum BA (8.0 and 16.0 mgl^-1) and kinetin (8.0 to 32.0 mgl^-1) were as effective as 2,4-D in inducing somatic embryogenesis. Polyembryonic variety Vellari Manga showed better response to induction treatments than the mono embryonic varieties. B5 major salts with MS minor salts in combination with 40 gl^-1sucrose, 10 gl^-1PVP, 200 mll^-1coconut water, 5.0 mgl^-1 ABA, 100 mgl^-1 casein hydrolysate and 6.0 gl^-1agar were the best suited for the maturation of the somatic embryos. The positive influence of cobalt chloride, casein hydrolysate and coconut water on the germination of embryoids of both mono and poly embryonic mango varieties could be well established. A basal medium consisting of B5 major salts and MS minor salts supported the highest percentage of germination of somatic embryoids in Neelum and Vellari Manga. However, abnormalities in germination were observed in most of the cases. Excellent germination of somatic embryos was observed in a liquid medium consisting of half strength B5 macro salts and full strength MS micro salts and supplemented with GA3 1.0 mgl^-1+ glutamine 400 mgl^-1 + sucrose 30gl^-1.

Waste is not actually waste but is the by-product of various activities of human life. The unclean handling of these wastes creates problem for public health departments and local bodies. The classification of waste depends on the agencies that classify these wastes according to the area of interest and method of disposal viz. medical field, agricultural field, local bodies, industries etc.

In the present paper, the emphasis is given to the classification based on agricultural activities which includes a) Agricultural marketing waste b) Meat and fish marketing waste.

ABSTRACT

Commercial propagation using tissue culture techniques started in seventies for orchids in USA. Since then, the science and technology of tissue culture have advanced particularly after the development of the most widely used medium by Murashighe and Skoog (1972). The science has led to the development of the fascinating area of gene transfer. Today, micropropagation protocols are available for almost all horticultural crops. But, there are certain grey areas where research need to be intensified to solve the problems confronting certain difficult to propagate species belonging to plantation and spice sectors. The major area that needs to be addressed is recalcitrance.

ABSTRACT

The Plant Growth Promoting Rhizobacteria (PGPR) is a group of rhizosphere-colonizing bacteria producing substances which increase the growth of plants and/or protect plants against pathogens. The use of PGPR has become rather common practice and is on the rise in many regions of the world. Inoculation with PGPR also aims at reducing the application of potent ially pollut ing chemical fertilisers and pesticides. Biocont rol microorganisms have unquestionable potential for managing plant diseases, insect pests and nematodes besides increasing crop productivity. Interest in biological control has recently been intensified because of imminent bans on effective pesticides, widespread development of pesticide resistance in insect pests and plant pathogens and a general need for more sustainable pest control strategies. Active and long-term colonization of the root surface of the plant and effective expression of disease-suppressive traits are generally considered prerequisites for successful suppression of horticultural crop diseases by rhizobacteria. The important mechanism of biocontrol by PGPR involve competition and production of antibiotics such as 2,4-diacetylphloroglucinol (DAPG), pyoluteorin (PLT), pyrrolnitrin, phenazine-1-carboxylic acid (PCA), 2^-hydroxy phenazines and phenazine-1-carboxamide (PCN). Siderophores, including pyochelin and pyoverdine which chelate iron and other metals also contribute to disease suppression by conferring a competitive advantage to biocontrol agents for the limited supply of essential trace minerals in natural habitats. Induced systemic resistance (ISR) is a state of increased defensive capacity developed by the plant when appropriately stimulated, through activation of latent resistance mechanisms induced by diverse agents including rhizobacteria. Microplants are first grown in vitro under aseptic conditions devoid of microorganisms. They are then transferred to a post vitrum substrate for acclimatization. By creating a beneficial rhizosphere in microplants at an early stage, the plants could be better protected against biotic and abiotic stress that occurs in the greenhouse or in the field. The beneficial rhizosphere can be created by biotization of microplants with PGPR. The search for PGPR to control postharvest decay of fruit crops has been actively pursued and promising strategies have been practiced nowadays. Biological control of postharvest diseases of perishable horticultural crops with PGPR is complex and involves a number of mechanisms to suppress the development of the disease. PGPR, being a potential candidate in disease management through multiple mode of action, it becomes highly imperative to know its different role in the management of plant pathogens.

Introduction

The common mycorrhizal association in most of the plants is the arbuscular type occurring in the majority of agricultural and horticultural crops. Arbuscular mycorrhizae (AM) are formed by non-septate Zygomycetous fungi belonging to the genera Glomus, Gigaspora, Acaulospora, Sclerocystis, Entrophospora, Scutellospora, Archaeospora and Paraglomus in the order Glomales. These fungi are obligate symbionts and have not been cultured on nutrient media. These endophytes are not host specific although evidence is growing that certain endophytes may form preferential association with certain host plants. Several investigations indicted that even in unsterile soils plants do respond to inoculation with efficient strains of arbuscular mycorrhizae. Numerous experiments have been conducted in different parts of the world confirming this growth improvement. The increased growth of mycorrhizal plants is favoured in soils with low to moderate fertility. More specifically, soils favouring mycorrhizal growth stimulation usually have one or more essential nutrients, especially phosphorus, in limiting concentrations.

The mechanism of improved plant growth caused by mycorrhizal inoculation has been investigated by many workers. Greater soil exploration by mycorrhizal roots as means of increasing phosphate uptake is well established. They also improved the uptake other diffusion-limited elements like Zn, Cu, etc. The other beneficial effects are their role in the biological control of root pathogens, biological nitrogen fixation, hormone production and greater ability to withstand water stress (Bagyaraj, 1984).

Introduction

Increasing production of cereal crops, oil seed crops, and horticultural crops is becoming more important than ever before owing to increasing population and changing food habits of the people. The modern tools of biotechnology are being exploited to the fullest throughout the world for developing transgenic crop plants with improved traits. Already about 20 countries in the world are growing transgenic crops, predominately with traits such herbicide tolerance and resistance to insect-pests. However, there is a constant fear of pollen flow from theses transgenics to the neighbouring non-transgenic fields or to their weedy or wild relatives. It has become a matter of great concern to all biotechnologists to develop alternative strategies to prevent the pollen flow.

The best alternative strategy available today to circumvent the nuclear- transformation associated bottlenecks in developing tenable crop transgenics is the chloroplast transformation technology. This technology allows introduction and insertion of foreign genes into the chloroplast genome, called plastome. Chloroplasts are the site for photosynthesis in plants mostly present in leaves. In general called plastids, they are also present in other parts of the plant. For example, chromoplasts in coloured leaves and fruits, amyloplasts in starch storing organs, leucoplats in roots, and etioplasts in dark-grown seedlings. The plastids arise from proplastids - the undifferentiated form of plastids present in most plant cells. Just like nucleus, these plastids (and also mitochondria) contain their own genetic material on the chloroplast genome.

ABSTRACT

Of the total production of the crop yield, only 63 per cent is available for human consumption. The remaining is lost in more or less equal proportions to weeds, pests and diseases. Prior to genetic engineering, the exchange of DNA material was possible only between individual organisms of the same species. In the field of agriculture for instance, farmers have continuously modified naturally occurring species through seed selection and controlled breeding. With the advent of the recombinant DNA technology, it has however been possible to identify specific genes associated with desirable traits in one organism and transfer those genes within and beyond the boundaries of species into other organisms.

1. Genes for herbicide resistance

Modern agriculture has developed a range of effective herbicides to tackle the effects of weeds on crop yield. Some of the most useful of these are broad-spectrum herbicides because they are active against a wide range of weeds. However, these can only be used at times when the crop is not itself vulnerable to herbicide action. The development of herbicide-resistant crops therefore offers the opportunity to spray crops at the most effective time to kill weed species without damaging the crop plants. By definition, herbicides are much more toxic to plants than to animals. Therefore, it is not surprising that they generally affect ‘plant-specific’ biological processes. The herbicidal activity of many herbicides has been found to result from the specific inhibition of a single enzyme/protein. The following are four distinct strategies for engineering herbicide resistance: i. Overexpression of the target protein, ii. Mutation of the target protein, iii. Detoxification of the herbicide, using a single gene from a foreign source and iv. Enhanced plant detoxification.

ABSTRACT

The coastal ecosystem happens to be one of the most productive ecosystems. This ecosystem has been under different kinds of threats such as climate change and consequent rise in sea level, increase in population and depletion of natural resources. All this has given rise to an increase in the level of abiotic stresses such as salinity, alkalinity, and drought affecting the agricultural productivity in the coastal region. Salinization is posing an increasing problem in coastal and agricultural areas reducing plant productivity and yield. Salinity is one of the major abiotic stresses decreasing the plant productivity.

Salinity is a significant factor limiting agricultural productivity and affecting about 9x 10⁸ hectares worldwide. Poor quality of water for irrigation and current unsustainable irrigation practices has significantly resulted in salinization and other forms of soil damage. About one third of all irrigated land is affected by salt due to secondary salinization. It is estimated that 50% of all arable land will be salinized by the year 2050. The problem of secondary salinization is also becoming more serious as it represents loss of highly productive lands. Added to this is the problem of coastal salinity where intrusion of seawater into arable land due to erosion of coastal habitat has rendered it unsuitable for cultivation. Salt-affected soils (~11 million ha in South and Southeast Asia) are found along coastlines or in inland areas where evaporation is greater than precipitation.

ABSTRACT

The process of developing new crop varieties involves many steps and takes several years. In recent times, biotechnological advances have helped in reducing these considerably. Apart from the techniques of haploid culture and genetic engineering, one of the tools which is making it easier for scientists to select plant traits and develop new varieties is the use of molecular markers. Molecular markers can be used for (a) characterization of germplasm (b) varietal identification and clonal fidelity testing (c) assessment of genetic diversity (d) validation of genetic relationships and (e) marker- assisted selection. These have widespread applications in management of genetic resources as well as in breeding programmes. Marker-assisted selection has practically revolutionized breeding programmes. Traditionally, plant breeders have selected plants based on their visible or measurable traits called the phenotype. But this process can be difficult especially in the case of multigenic or quantitative traits. Molecular markers can be used to trace linkages with traits of importance. In the area of horticulture, this is a very useful tool in tree breeding, where the breeder has to wait for several years for phenotypic expression of the desired trait. A number of DNA marker technologies are now available and rapid advances are being made in the development of more sensitive marker technologies. The techniques involved, the various applications of DNA marker technologies in horticultural crops and future perspectives in the national context have been discussed.

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.

Botany

Cauliflower is highly cross pollinated crop due to self incompatibility. Flower is protogynous in nature. Stigma remains receptive 5 days before and 4 days after opening of the flower. The time taken from pollination to fertilization is 248 hours depending upon the temperature. The optimum temperature for fertilization and seed development is 12°C – 18°C. Bees are the major pollinators.

Method of seed production: There are two methods of seed production

1. in situ method (seed to seed method)
2. Transplanting method (Head to seed method)

For seed production, seed to seed method is recommended since the head to seed method in India has not been very successful. In seed to seed method (In situ method) the crop is allowed to over winter and produce seed in the original position, where they are first planted in the seedling stage.

ABSTRACT

Activity patterns of Grey Jungle fowl, Gallus sonneratii were studied at Gudalur Range (9º 37’ N, 77º 16’ E) which is 23² km area in Theni Forest Division, Western Ghats, Tamilnadu from January to December 2005.

ABSTRACT

In social Hymenoptera, the females carry out nest building, brood care and foraging, while males generally do not take part in any of these social behaviours and act solely as reproductives. The interesting phenomena of cooperation and altruism

Botany :The cabbage plant, Brassica oleracea, is an herbaceous annual or biennial vegetable in the family Cruciferae grown for its edible head. The head of the cabbage is round and forms on a short thick stem. The leaves are thick and alternating with wavy or lobed edges and the roots are are fibrous and shallow. The plant produces large yellow flowers. The densely leaved heads can range in size from 0.5 to 3.6 kg (1-8 lb) depending on variety. The plant is usually grown as an annual.

ABSTRACT

Queens of 4 post-emergence colonies of primitively eusocial wasp, Ropalidia marginata were observed for their propensity to acquire and handle foraged material on naturally occurring free foraging nest. The queens were inclined to acquire pulp loads than food loads. 

ABSTRACT

The coconut eriophyid mite, Aceria guerreronis Keifer is a serious pest of coconut in Kerala, Tamil Nadu, Karnataka, Andhra Pradesh, Orissa, West Bengal, Maharashtra and Gujarat. The mites reside underneath the perianth of nuts and feed on the soft meristematic tissues of the young nuts. Their feeding damage is evident as scars on the surface of the older nuts. The damage results in reduction in size of nut and increases labour for dehusking the nuts.

ABSTRACT

Folivorous bats consume flowers and fruits, effecting seed dispersal and pollination. Adaptation of plants according to the type of pollinator is called pollination syndrome. Some of the adaptations of bat-pollinated syndromes are nocturnal anthesis

ABSTRACT

The Indian short-nosed fruit bat, Cynopterus sphinx is one among the three paleotropical species known to make tents. Once a tent is made, male typically defends it against other competing males and also defends the females who join his tent.

ABSTRACT

Benthic fishes represent a significant component of riffle communities. Our 10 year study on two benthic fishes, Crossostoma lacustre and Rhinogobius candidianus which are sympatric in Hapen Creek, Northern Taiwan, reveals that these species exhibited mesohabitat overlaps but were segregated at the microhabitat levels. Both species preferred riffles and avoided rocks. Heavy flow (typhoons) had an inhibitory effect on the fish densities. The fishes may not be able to swim against the strong currents and might get carried away downstream. The recovery time (number of days after a peak, when the densities were restored to normalcy) for C. lacustre was = 13 days and for R. candidianus, it was = 16 days. Recovery was faster at the downstream (~13-15 days) as opposed to upstream (~1416 days). Direct estimation of the linkage between the hydrological or geomorphological variables and the well being of fish populations is one of the first steps in formulating an efficient, effective conservation plan or restoration strategy to preserve these species for the future.

ABSTRACT

Tropical wet evergreen and tropical moist deciduous forests were the preferred habitats of the Brown-hawk Owl. Detection rate and response to the broadcasted calls were highest during the breeding season and in all the census points, more than one individual i.e. either in pair or three individuals were detected. Besides conspecific species, some heterospecific species were also found to respond to the broadcasted calls of Brown-hawk Owl, where the Brown-hawk Owl was not detected during the Initial Quite Listening survey. Moreover, approach of the sympatric species was observed only in the riparian strip and in rest of the habitats they responded only with calls. No significant seasonal difference was observed in the habitat utilization but seasonality was observed in the response and the approaching distance to the conspecific calls broadcasted. Additionally, the response to the conspecfic calls indicated that the owls were responding to the conspecfic calls throughout the year.

INTRODUCTION

Molecular tools generally refer to molecular genetic tools. Although the first use of these tools began more than four decades ago, whenLewontin & Hubby (1966) used allozymes to find out the amount of genetic variation present in wild populations of Drosophila, the lack of expertise and high cost of these tools have prevented their widespread use among ecologists in general and behavioural ecologists in particular. But recently the accessibility and costs of these techniques have come down a lot and with the right kind of collaboration, lack of expertise is no longer an issue.

As was mentioned above, the Lewontin & Hubby’s (1966) investigation was done using allozymes. Although still an option, user-friendly neutral nucleotide markers are more preferred by investigators nowadays. The discovery of the polymerase chain reaction (PCR) in 1983 by Kary Mullis was the single landmark in this field, if one has to mention one. The use of molecular markers has totally revolutionized the field of ecology. It has provided ecologists the tool to ask questions, which were hitherto impossible to tackle and also to answer questions with much more precision and accuracy than was possible till now. It has toppled long held beliefs, sometimes, romantic ones, by ecologists.

ABSTRACT

The Indian false vampire bat, Megaderma lyra detects and captures prey (e.g. frogs) mainly by listening to the rustling sounds that are created when the prey is on ground. In addition, echolocation and vision are also involved. Mothers of M. lyra take meticulous care of their young. At the age of about seven weeks, juveniles exhibit gleaning flights. Among eight mother-young pairs, four young (group A) began to capture frogs at the age of 62 days

ABSTRACT

Insects are considered the most successful in the animal kingdom. Many factors contribute to their success. One major factor that operates strikingly is the economy and optimal use of energy. One can give several examples taking the life of a single insect

ABSTRACT

Ethology, the biology of behaviour has been a fascinating area of biological investigations during past few decades. In recent past the information gathered by reputed ethologists on social behaviour of insects, fishes, birds and human beings are very helpful in the application of these principles for the welfare of the humanity as well as for the environmental sustainability. Ethology differs from the study of Animal Behavior, in that animal behaviorists generally are interested in learned behaviors while ethologists concentrate on innate behaviors.

ABSTRACT

Male crickets use acoustic signals for long-distance mate attraction. Each cricket species has a unique calling song, used by females to recognize and localize conspecific males. Field cricket songs have wavelengths of several centimeters, which pose a difficult problem for these small animals in terms of localizing males, particularly in choruses. The chorus structure in terms of spacing, call intensity and timing, are important determinants both of the ability of males to synchronise their calls and of female mate-finding strategies.

ABSTRACT

Social primates appear to be knowledgeable about one another’s behaviour to different extents. But do they know as much about one another’s beliefs and intentions? Are they adept at recognizing the similarities and differences between their own and others’ states of mind?

ABSTRACT

Science essentially involves confronting our ‘models’ of nature, against data from the real world, in a continuous effort to refine our knowledge of the system under study. Scientific monitoring of animal populations is therefore best viewed in the context of questions such as why monitor, what to monitor and how to monitor.

ABSTRACT

Malabar Spiny Dormouse (Platacanthomys lasiurus), the endemic rodent found in the Western Ghats of South India was studied in the Peppara Wildlife Sanctuary, Thiruvananthapuram District, Kerala, to determine the status, distribution, food and feeding of the species.

ABSTRACT

Insect societies such as those of ants, bees, wasps and termites are characterized by reproductive division of labour and cooperative brood care. Thus these societies consist of one or a smallnumber of reproductives (usually only queens but also kings in the case of termites) and a large number of sterile or nearly sterile workers

ABSTRACT

Studies on the behaviour of animals are of utmost importance in the conservation of species. Ecology of the communities and individual species has to be examined in terms of different activities to understand the requirements of the species. Foraging and breeding are the major activities while resting and flight maintenance are also essential, although the time spent might vary in different species or situations.

Bird community studies conducted along with my students in different habitats in the Western Ghats since 1995 showed how the species are associated with each other and the impact of habitat changes on them. Endemic and threatened birds of the Western Ghats were specific about selection of habitat and food in different seasons. Identification of such critical habitats is crucial for conservation and management.

The studies on the bird community and drongos at Thekkady, Periyar Tiger Reserve conducted by me during 1979 to 1982, examined the association of drongos with other species in the area, especially while foraging. They fed mostly in mixed foraging flocks which is beneficial to all the participants. The strategy adopted by them for ecological isolation to reduce competition was by selecting different strata and substrate of the vegetation, varying sizes of insects, and methods of feeding.

In the case of wetland birds also habitat selection is a major behaviour limiting their numbers. For the threatened birds such as the Siberian Crane and the Andaman Teal, habitat quality and food availability were critical. Habitat degradation with over abundance of grass and reduction in sedges resulted in spending long duration for feeding and less returns.

Breeding behaviour of birds is interesting because of their strategies such as when to nest and where to nest. Studies on the seasonality have shown the importance of climatic factors. Many of our land birds nest during summer. Nest-site is also crucial as selection of the site with suitable macro and micro-habitats determine the success of the brood. The habitat patches for the individual pairs or groups of breeding birds which are defended against intruders are termed as territories which play a vital role in the distribution and density of birds. Thus the strategies adopted by species are dependent on the environment and species specific constraints affecting the survival of the species.

ABSTRACT

Education begins at home, then in community and finally in the educational institutes. At present 90% of the children in the age group of 6-14 years are receiving free primary education. Education policy of the 11^th plan states that there should be free and compulsory secondary education for all. To meet this goal, additional schools have to be set up to cater to the 30 million students. To teach the 30 million students atleast one million teachers would have to be trained to ensure the 1:30 teacher– student ratio. How do we plan to meet this target?

The projected target has to be met by developing innovative teaching methods in the institutes of higher learning. These methods have to be technology based, as well as community based regional approach. Emphasis has to be given to Liberal Education where there has to be a close interaction between the teacher and learner. The Open and Distance Learning isone such System which can be compared to Liberal Education– where there is flexibility in time and pace of learning for the learners. Reforms and innovations have to be brought in this system of education with utmost caution so that there is no compromise on quality and ethics, since every age has its own ethical environment.

Ethics in this context means traditions and culture of the small communities. This is more so in the North Eastern Region where there is an intimate connection between large and small communities. This region is rich in its community based values, bioresources and cultures. Need based Vocational and Professional courses have to be designed for enriching the region with human resources infused with sophisticated skills, resulting in the economic growth for the region. This method is envisaged to take care of the social challenges, traditions and cultural ethos.

Distance Education coupled with Information Communication Technology plays a pivotal role in meeting the requirements of today’s knowledge society by cutting across the barriers of time and geographic isolation.

ABSTRACT

Bats: A colony of 500 insectivorous bats of Hipposideros speoris inhabited a natural cave in Madurai (9^O58’ N. lat; 78^O10’ E long). At a depth of 40 m, the cave experiences a constant temperature of 27 + 0.1^OC, 95 % relative humidity and absolute and perpetual darkness. Therefore there were no day/night cues. Yet all the members of the bat colony flew out 10 to 15 min. after sunset as though they knew the time of sunset. Recorded flight and rest experiments in flight activity cages and a hand-wound Thermohygrograph drum 40 m from the cave mouth over periods of 50 days revealed that the free-flying conspecific bats were socially synchronizing the activity patterns of the three captive bats. Bats were telling other bats time.

Mice : In the field mouse, Mus booduga the mother conveys information of day and night to her pups by means of her presence and absence (PA) cycles. Her presence meant day and absence denoted night. We named this phenomenon maternal entrainment. Such entrainment of the time sense of the pups was possible if in every cycle the mother was presented for a minimum of 8 hr but not exceeding 16 hr. Therefore 8 hr and 16 hr describe the limits of maternal entrainment.

Elephant foot yam is an underground stem tuber belonging to the family Araceae, one of the most popular tuber crops, extensively used as a favourite vegetable by millions of people in India. It has both nutritional and medicinal value and is usually consumed as cooked vegetable. It has high dry matter production capability per unit area than most of the other vegetables. Elephant foot yam is a remunerative and profitable stem tuber crop. The crop is gaining popularity due to its shade tolerance, easiness in cultivation, high productivity, less incidence of pests and diseases, steady demand and reasonably good price.

Botany

The plant is highly cross pollinated due to heteromorphism and bees being the major pollinators.

Varieties: PKM 1 & PKM 2

Method of seed production : Seed to Seed.

Land requirement : Uproot all the wild and non specific moringa trees if any near the field within a radius of 1500ft. Good drainage facility is must for moringa.

Isolation requirement : A distance of at least 500 M is necessary for seed production.

Season : Early season (July August), Mid season (September), Late season (October -November). Best season is September October, so that flowering starts during summer which facilities better pollination and seed set.

Abstract

The landslides of the hill ecosystems are either due to the natural morphotectonic and morphodynamics processes of the planet earth or due to the anthropogenic effects or due to the combinations of the both. In the Indian subcontinent, the landslides are reported from three major provinces viz: Himalayas, Westernghats and The Nilgiris. While the landslides of the Himalayas are demonstrated to be predominantly due to active tectonics, the landslides of the Westernghats are attributed to excessive weathering and rock fall. On the contrary the landslides of the Nilgiris have been thought to be due to extensive deforestation and the related increase in the pore pressure during rainy seasons. But the studies carried out in the recent years show that not only in the Nilgiris but also in other hill systems of Tamil Nadu, the landslides seem to be related to the recent earth movements. This is very significant in the context of fastly recurring seismicities in South India and hence this aspect warrants detailed studies for landslide mitigation.