NISCAIR Online Periodicals Repository Collection: IJBT Vol.04(1) [January 2005]

Transgenic cabbage (Brassica oleracea var. capitata) resistant to Diamondback moth (Plutella xylostella)

Wed, 29 Dec 2004 22:58:59 GMT

Title: Transgenic cabbage (Brassica oleracea var. capitata) resistant to Diamondback moth (Plutella xylostella)

Authors: Paul, Anderson; Sharma, S R; Sresty, T V S; Devi, Shantibala; Bala, Suman; Kumar, P S; Saradhi, P Pardha; Frutos, Roger; Altosaar, I; Kumar, P Ananda

Abstract: A synthetic fusion gene of Bacillus thuringiensis encoding a translational fusion product of Cry1B and Cry1Ab δ-endotoxins was transferred to a tropical cabbage breeding line by Agrobacterium-mediated transformation. Selection of transformants was carried out on media containing kanamycin. Polymerase chain reaction (PCR) analysis revealed that twelve of the putative transformants contained the transgene. Insect bioassays carried out with the leaves of PCR-positive plants and neonate larvae of Diamondback moth (DBM) showed that one of the transgenic plants was completely resistant to repeated infestation by the larvae. Southern hybridization confirmed gene integration in the DBM-resistant plant. Double-antibody sandwich Enzyme-Linked Immunosorbant Assay (ELISA) analysis revealed accumulation of fusion protein up to 0.16% of total soluble protein in the leaves of the transgenic plants. Progeny (T₁ generation) of the selfed transgenic plants were analyzed for the transgene segregation and insect protection. These studies clearly demonstrated the efficacy of Cry1B-Cry1Ab fusion protein to confer protection to cabbage against DBM infestation. The transgenic cabbage plants will serve as a good system to study the role of gene pyramiding in resistance management strategies intended to prevent evolution of resistance in DBM.

Page(s): 72-77

Post-harvest biotechnology of fruits with special reference to banana— Perspective and scope

Wed, 29 Dec 2004 22:58:59 GMT

Title: Post-harvest biotechnology of fruits with special reference to banana— Perspective and scope

Authors: Surendranathan, K K

Abstract: Fruits, being highly nutritive, are important component of human diet but they possess very short post-harvest shelf life. As ripen, they become very soft and more prone to injuries, which makes them highly perishable. In India, over 30% of the annual produce is wasted due to spoilage. Hence, there is an urgent need to develop technologies to overcome post-harvest losses of fruits. Physiologists and biochemists attempted to extend the shelf life of fruits by different means though the results were not very satisfying. It was demonstrated recently that a judicious dose of g-irradiation (0.1-0.5 kGy) could enhance the shelf life to fruits by about a week to a fortnight, which could help in minimising the spoilage during storage and transportation. However, stringent quality controls have to be strictly followed to get the best results. Studies revealed that g-irradiation brings alterations/changes in metabolic pathways, which delay the production of essential precursors and energy required for ripening of fruits. Another strategy, to enhance the shelf life of fruits, could be adopted through regulation of endogenous ethylene production. Most recent studies have shown that it could be achieved by such genetically modified (GM) crops where gene expression of key enzymes responsible for ripening, like PG-ase, EFE and ACC-synthase, by means of antisense RNAs. However, adoption of this technology has so far been deterred due to apprehensions of safety issues associated with GM crops. An alternate method for prevention of spoilage of fruits as well as sustaining the interests in farmers could be the value addition of fruit commodities. This could be achieved by improving the conventional methods as well as development of non-conventional products of commercial interest. Nuclear Agriculture and Biotechnology Division, BARC has developed processes for the production of juice and powder from ripe banana, the largest produced and maximum wasted fruit, by creating an in-built mechanism to inactivate the pectin forming enzymes. With this process, over 60-80 % of the total moisture of the fruit is extracted out as juice. The commercially available variety, ‘Harichal’ (Mumbai kela) could give juice 550-640 ml /kg pulp. It is also demonstrated that a number of products of commercial significance, like banana nectar, carbonated juice and wine, from banana juice and biscuits, cakes, milkshakes, etc. from banana powder could be developed.

Page(s): 39-46

Effect of bioinoculants on biomass productivity under agroforestry systems

Wed, 29 Dec 2004 22:58:59 GMT

Title: Effect of bioinoculants on biomass productivity under agroforestry systems

Authors: Sharma, Satyawati; Kashyap, Suman; Vasudevan, Padma

Abstract: Efficacy of native bioinoculants, viz. AM fungi and Azotobacter, separately as well as in combination was evaluated for enhancing biomass productivity of Morus alba, Populus deltoides, Psidium guajava and Leucaena leucocephala under different agroforestry models along with other plant species. The combination of all plant species tested was found to be favourable with respect to growth, yield and microbial population in soil. The combined inoculation of AM fungi and Azotobacter gave the best results. AM fungi were cultured on Zea mays, Trigonella foenum-graecum, Ricinus communis, Vigna radiata, Solanum melongena and Lycopersicon esculenum, wherein R. communis was found to be the best host plant.

Page(s): 156-160

Cloning and expression of bovine (Bos indicus) interleukin-2 in Escherichia coli

Wed, 29 Dec 2004 22:58:59 GMT

Title: Cloning and expression of bovine (Bos indicus) interleukin-2 in Escherichia coli

Authors: Patil, Amar A; Saini, Mohini; Sharma, Sameer; Bind, R B; Gupta, Praveen K

Abstract: The gene for interleukin-2 (IL-2) was amplified from cDNA pool prepared from ConA-stimulated peripheral blood mononuclear cells (PBMCs) isolated from Indian cattle (Bos indicus). The amplified IL-2 gene was cloned and nucleotide sequences were determined. Homology comparison of nucleotide and predicted amino acid sequences revealed similarity of sequence and conservation of crucial amino acids with exotic cattle (B. taurus). The coding sequence of IL-2 (without its own signal sequence) was subsequently expressed as fusion protein with polyhistidine fusion tag in Escherichia coli, using prokaryotic expression vector. The expressed protein was present as insoluble inclusion bodies. The recombinant protein was solubilized with urea and purified using Ni-agarose affinity chromatography. The purified recombinant IL-2 was characterized in SDS-PAGE and in western blotting.

Page(s): 88-92