Bakar, U. A.

Mahmood, Marziah

Sim, S. M.

Universiti Putra Malaysia Institutional Repository

DEVELOPMENT OF MOLECULAR BREEDINGTECHNOLOGY FOR PEPPERFOR Category F10800: Biological SciencesM.Marziah, IS.M. Sim, 2U.A. BakarDepartment of Biochemistry and MicrobiologyUniversiti Putra Malaysia, 43400 UPM, Serdang, Selangor,MalaysiaIDepartment of Agriculture, Semenggok, Sarawak,l Biotechnology Center, MARDIKeywords: molecular plant breeding, genetic engi-neering, transformation, controlled ripening, antisense.IntroductionDue to asynchronous flowering, fruits of pepper do not ma-ture at the same time. Harvesting is carried out several roundof manual picking. This resulted in a high labour output. Itis, therefore, desirable to develop pepper genotype with syn-chronous fruit maturation characteristics so harvesting can bedone in one round and probably via mechanisation. This willreduce cost of production significantly. The antisense tech-nology and genetic engineering techniques have been used todevelop tomato plants with delayed ripening characteristics.Similar work will be carried out for black pepper. The objec-tives of the study were: To develop a molecular plant breed-ing technology for vegetatively propagated crop using blackpepper as a model and to apply the antisense technology forthe production of delayed ripening characteristic in blackpepper.Materials and MethodsTrue to type black pepper plant's leaf and stem were used inthe regeneration of callus and new axenic plants. Due to thecontamination problem encountered using true to type ex-plant, seeds were germinated in vitro to obtain axenic plants.Genetic transformation studies are carried out using Agro-bacterium-mediated system.Results and DiscussionThe highest percentage of explants with multiple shoots afterone month was at 0.5 mgll BAP. The same range of concen-tration was also carried out with zeatin and kinetin. However,these two hormones did not induce any multiple shoots onstem-nodes. Besides that, callus initiation of leaf, petiole andstem was also carried out using auxins such as NAA, 2,4-D,IAA and Picloram. The concentration used was 0, 0.1, 0.5,1.0, 2.0 and 5.0 mglL. From the treatments carried out, all-the explants produced callus at different concentration ofauxins. Besides producing callus, NAA and IAA also pro-duced roots from the explants especially leaf and stem. In-duction of callus from nodal pieces in MS medium was alsocarried out using NAA at concentration of 0.5, 1.0, 2.0, 3.0and 5.0 mg/L combined with BAP at 0 and 0.2 mgIL. Fromthe results obtained, all combinations produced callus and insome cases roots were formed in the medium with no addedBAP. Calluses subcultured in MS + 0.5 2,4-D + 2.5 kin andkept in dark for about 1-2 month gave quite whitish newcallus. Observation on one leaf explant cultured in Yz MS+0.5 2,4-D + 2BAP showed direct regeneration after about 2months. Multiple shoots also observed in stem cultured inMS + 3 IBA + 1.5 BAP after about 2 months. Leaf samples,which have been inoculated with Agrobacterium, were as-sayed for gus activity. The expression of the gus gene wasindicated by the blue histochemical reaction. So far, gus ac-tivity was only detected on leaf explants at 10 days after in-oculation with a 1:10 dilution of Agrobacterium tumefaciens.On the other hand, assay of the npt II gene activity by PCRfailed to detect the expression.ConclusionsPlant regeneration was achieved from true to type explantsand gus activity was observed in leaf explants indicatingtransformation has been successfully carried out.Supported by IRPA Grant 01-02-04-0267193

Development of molecular breeding technology for pepper

http://psasir.upm.edu.my/42438/1/Development%20of%20molecular%20breeding%20technology%20for%20pepper.pdf

Development of molecular breeding technology for pepper

Abstract

Similar works

Full text

Available Versions

Universiti Putra Malaysia Institutional Repository