Abstract:The effects of applied nitrogen (N) doses on crude protein and amylose accumulation in rice grains on primary and secondary rachis branches and their palatability were examined. The crude protein content of rice grains on both primary (PRB) and secondary rachis branches (SRB) increased with the increase in N supply showing a strong negative correlation with palatability. The correlation coefficient between protein content of the grains on PRB and SRB was -0.92 and -0.98, respectively. Although the amylose content also decreased with increasing N supply, the change was not significant on either PRB or SRB. However, it showed a good correlation with palatability; i.e., the correlation coefficient on PRB and SRB was 0.93 and 0.84, respectively. Analysis of protein by SDS-PAGE showed that the contents of protein bodies PB-I and PB-II, were correlated with palatability, but the latter had a higher correlation. The grains on PRB showed a higher palatability than those on SRB due to the difference in the accumulation pattern of proteins and amylose. These results suggest that when breeding for varieties with good palatability, the plants with more grains on PRB should be selected and by maintaining the nitrogen level in the field, we can control protein accumulation and thus can improve the palatability of rice crop.

Cotyledon explants of two Oriental melons produced hairy roots when cultured on Murashige and Skoog basal medium after infection by the Agrobacterium rhizogenes. Hairy roots were produced from the wounded surface of the cotyledon explants of Cucumis melo L. cv. Geumssaragi-euncheon on Murashige and Skoog selective medium and 86% of the GUS stained hairy roots were positive for the expression of beta-glucuronidase. The insertion of the gfp-gus fusion gene in the genomic DNA and the presence of the gfp-gus-specific transcript in the total RNAs of transgenic hairy roots were confirmed by PCR and RT-PCR, respectively. An immunoblot analysis of the transgenic hairy root extract revealed 97 kDa single bands coincident with the molecular weight of the GFP-GUS fusion proteins. ELISA demonstrated that the highest level of GFP-GUS fusion protein expression was 0.47% of the total soluble protein in a transgenic hairy root. The MS medium showed the fastest growth among three media types tested. Infection of the hairy roots with a root-knot nematode resulted in the development of a mature egg mass about 4-5 weeks after inoculation. The highest number of egg mass was obtained on the hairy roots cultured in SH medium containing 0.3% agar.

In September 2013, we discovered sooty mould growing on kenaf with the extrafloral nectaries in Iksan, Korea and identified the causative fungus as Leptoxyphium kurandae based on morphological characteristics and phylogenetic analyses. This is the first report of sooty mould caused by L. kurandae on kenaf in Korea and globally.

In this study, we collected 29 Kenaf (Hibiscus cannabinus L.) genetic resources from 10 countries to confirm the possibility of the introduction into Korea. The Kenaf (Hibiscus cannabinus L.) has the broad industrial use like feed and the 5 times more strong CO2 absorption capacity compared to general plant. So recently it is considered as a good industrial source. We analyzed ecotype, growth and development, yield and feed value of collected resources. They were divided into 3 groups depending on flowering time, early maturing type blooming in early July, mid-late maturing type blooming from end of August to early September and late maturing type blooming in end of October. Early maturing type could get fruitful seed but dropped yield (average 7,895 ㎏/10a) and late maturing type could get high yield (average 12,572 ㎏/10a) but deletion. The other side mid-late maturing type could get yield over a certain level (average 11,207 ㎏/10a) and fruitful seed was ensured. The yields analyzed by resources indicated that K12 (Hongma 300) collected in China, K25 from India, K22 from Russia and K21 (Khonkaen 60) variety from China were more than 13,500 ㎏ per 10a. Feed value of early maturing type had inclined to more better than other types, but like dry digestible matter (DDM) and dry matter intake (DMI) of some late maturing types like K12, K21, K22 which had a high yielding ability were more better than that of early maturing types'. So relative feed value (RFV) which considered comprehensive item for feed value were indicated K21 was 102.5, K12 was 116.2 and K22 was 120.2. 'Jangdae' the variety developed in Korea which could complement of other types' had a good quality for yield 10,975 ㎏/10a and 12.5% crude protein content and 101.9 of the relative feed value. So we need to be taken power to collection of mid-late maturing types resources.

Kenaf (Hibiscus cannabinus L.) was recognized as a potential source of forage. To reduce the production cost, we should insure large cultivation area. The one of the best candidate places to expand the useful kenaf production was 'Saemangeum' reclaimed land. To confirm the possibility of kenaf growth in reclaimed land, we seeding and cultivated the kenaf in 'Saemangeum'. The germination percentage of kenaf on 5.0 dS/m soil salinity was 18%. It is less 66% than that of 4.0 dS/m soil salinity and at 6.0 dS/m, the germination percentage of kenaf was under 10%. The growth and development of kenaf in reclaimed land grew worse with increasing soil salinity. The stem diameter which the most important factor that decide the value and yield of product was upper 2.6 cm when soil salinity maintained under 4.0 dS/m, but if soil salinity marked over 4.0 dS/m, the stem diameter of kenaf was drop under 2.0 cm and it deteriorate the number of leaves per plant by 20~46%. The necrosis on older tip and marginal leaves were noted approximately first month after seeding which was correlated directly with the salinity levels of reclaimed soil. Reduction of total yield was coincide with increasing levels of EC. If soil salinity over 5.0 dS/m, the amount of decreased by soil salinity was 51% than that of non-reclaimed region. The allowable soil salinity level of which could be maintained within 20% reduction rate was 4.2 dS/m. Consequently kenaf can be grown successfully with moderately saline soil condition. However, salt levels in excess of 4.2 dS/m severely have restricted plant growth and development and will result in significant yield reduction.