The investigated data for each genotype has been recorded on database by using database package program (Jaryomaeul, ver. 8.0). The data for the mulberry germplasm included are as follows; Photo of leaf, leaf length, leaf width, internordal distance, leaf shape, leaf color, leaf gloss, inflorescence, fruit length, fruit weight, sprouting date, cold tolerance, etc.
Now we are developing software with RDA team for integrated database and descriptor preparation as well as query based program for the mulberry germplasm to upload them on the web site.
Characterization of germplasm is essential to identify the individual genotypes which collectively indicate the extent of variability which exists among the accessions and to compare with each other for further investigation and utilization. The characterization is also a process in which highly heritable characters are subjected for systematic data recording that finally helps in identifying the different germplasm.
The comprehensive information on variability recorded helps the breeders for effective crop improvement. Enrichment of mulberry germplasm bank with high variability and the characterization of these resources is a continuous process for generating a strong database. A large number of morphological and agronomical characters are being evaluated for utilization in breeding programs.
Mulberry genetic resources are characterized and evaluated on the basis of morphological characters such as leaf and branch and agronomical characters such as sprouting day, cold resistance and disease resistance.
The Manual for the characterization and evaluation of mulberry genetic resources (Machii et al., 1997) is usefully utilized for characterization and evaluation of mulberry genetic resources. In addition, we are going to analyze the content of functional materials such as GABA and rutin of the genotypes for the utilization of mulberry as medical use.
The methods used to classify the genus Morus are primarily based on conventional systematic studies involving differences in growth form, leaf morphology, length of the styles in the female flowers, fruit color and other agronomical characters.
But morphological and physiological characteristics are not sufficient to differentiate some Morus genotypes because the differences between them are often subtle.
In order to identify the possibility of classification for the species by means of molecular biology, phylogenetic relationships among mulberry varieties(Morus species) were analyzed on the basis of nucleotide sequence variations in internal transcribed spacer(ITS) regions of ribosomal DNA and RAPD(Sung, 2000).
It is very important to share germplasm information for the utilization in breeding program.
The characteristic data about mulberry genetic resources in our country has already been accumulated and we are preparing to share by the Internet, which can be freely access all over the world.
We hope more and more countries often their information by publication or by Internet to enhance the utilization of mulberry genetic resources more effectively.
In order to use the information more efficiently, there should be unified methodology for evaluation and characterization of genetic resources.
We hope that FAO and ISC endeavor to develop unified methodology for evaluation and characterization of genetic resources.
References
Koizumi G. (1917) Taxonomical discussion on Morus plants. Bull. Imp. Sericult. Exp. stat., 3:1-62(in Japanese)
Machii H., A. Koyama, H. Yamanouchi and K. Katagiri (1997) Manual for the characterization and evaluation of mulberry genetic resources. Misc. Publ. Natl. Inst. Seric. Entomol. Sci., 22, 105-124. (in English)
Park, K.J. (1991) Mulberry variety with high-yield and good quality Shingwangppong and Cheongunppong. Res. Rept. RDA(F.M., A.E., and F.P.U.) 33(3): 50-63(in Korean).
Park, K. J.(2001) Characteristics mulberry fruits on Daeseongppong, Daebungppong, Daeokppong and Shinkwangppong(Morus Spp.). Korean J. Seric. Sci., 43(2): 99-103(in Korean)
Park K. J.(2001) History of 100 years on sericultural development in Korea(edited by Lee W. C.). p 3-35(in Korean).
Park, K. J., G. B. Sung and Y. K. Lee(2001) Fertility and characteristics of mulberry fruits on Daejappong and Garmbacppong(Morus Spp.). Korean J. Seric. Sci., 43(2): 93-98(in Korean)
Seki, H. and K. Oshikane(1959) Studies on polyploid in mulberry trees(III) The evaluation of breed polyploid mulberry leaves and the result of feeding silkworms on them. Research Reports of Faculty of Textile and Sericulture, Shinshu University 91: 6-15
Sung G. B., H. B. Kim and H. W. Nam (2001) Screening of mulberry genotypes suitable for fruit production and development of high-yielding strains with large fruits. Research report of NIAST in computerized file (in Korean).
Sung G. B and H. W. Nam(1995) Manual for the mulberry local adaptability test. Rural Develop. Admin.(RDA) 1-25(in Korean).
Sung G. B.(2000) Phylogenetic relationships of Morus species on the basis of ITS nucleotide sequences in ribosomal DNA and RAPD. Kyungpook National University (in Korean).
Sung, G.B (2001) A list of genetic mulberry resources maintained at National Institute of Agricultural Science and Technology. Unpublished(in Korean).
Tojyo I.(1966) Studies on the poliploid in mulberry tree I. Breeding of articifial autotetraploids. Bull. Sericul. Exp. Sta. 20(3): 187-207(in Japanese)
Fig. 10. Detailed information on 260 mulberry genotypes (Ichinose)