Biomass crops have potential as a source of renewable CO2-neutral energy to ease concerns about fossil fuel consumption. Therefore, there is an increasing interest in high biomass crops such as switchgrass (Panicum virgatum L.). Switchgrass is a perennial C4 grass that requires low cost for biomass production. In the previous study, we evaluated forty-six switchgrass germplasms for biomass yield and classified the germplasms into the high-, medium-, and low-yielding groups. In this experiment, we analyze physiological characteristics affecting biomass productivity and composition of organic compounds for the two selected lines from each biomass yield group. Among the characteristics related to carbon assimilation, photosynthetic rate, real CO2 absorption rate(Delta CO2(CO2 reference - CO2 analysis(corrected for dilution))), P.A.R incident on leaf surface, and chlorophyll content were positively related to biomass yield of the selected lines. Positive correlation was found between biomass yield and ash content but no relations were found between biomass yield and content of organic compounds such as lignin, glucose, crude protein, cellulose, holocellulose, hemicellulose, ADF, and NDF. This study was supported by Technology Development Program for New Bioenergy(subject number-20070301030016), Rural Development Adiministration, Republic of Korea.

The objectives of this study were to collect and maintain wild barley accessions and to analyze their phylogenetic relationships among the accessions. Sixty wild barley accessions were collected from Syria (four accessions), Jordan (eight), Afghanistan (six), Iraq (three), Iran (four), Turkey (two), Pakistan (one), Tajikistan (one), Azerbaijan (one), Palestine (fifteen), and unknown area (fifteen). Seeds of the three accessions failed to germinate. Thirty-seven random amplified polymorphic DNA (RAPD) were generated and the phylogenetic relationship of the accessions was analyzed. Large genetic diversity existed among the collections and the collections were classified into 4 groups at a similarity coefficient of about 0.7698. Significant variations were observed within the collections from the same geographical location. The collections have sufficient genetic and morphological diversity for the genetic and phenotyphic analyses of traits associated with tolerance to abiotic stresses such as salt and drought.

Major agronomic and morphological traits of Korean land races of cultivated barley were analyzed. Three hundred sixty-three Korean land races, 69 hull-less and 295 hulled barely, were cultivated at the field of National Honam Agricultural Research Institute at Iksan, Korea. Olbori and Saessalbori were used as control varieties for hulled and hull-less barley, respectively. Traits such as heading date, maturity, plant height and flag leaf length and width were analyzed. Heading date and maturity were variable 22 and 22 days, respectively, among the land races tested. Plant height of land races corresponded to 74 to 174% of that of the control varieties. Flag leaf length and width varied from 87% to 314% and from 57 to 233%, respectively, of that of the control varieties. This result indicates that genetic diversity for agronomic and morphological traits are significantly broad among Korean land races and they could provide valuable genes to improve current elite lines.

본 실험은 보리 약배양에서 모식물체의 생육환경과 전처리 방법에 따른 배양효율을 검토코자 수행되었다. 캘러스 유기정도는 품종에 따라 0～5.6%의 범위를 보였고, 식물체 분화율은 캘러스 대비 0～30.0%이었으나 그중 녹색체는 0～4.4%로 낮았다. 동절기 온실과 춘계포장에서 각각 재배한 모식물체의 약배양 캘러스 유기율은 춘계포장 모식물체의 약에서 많았지만 식물체 분화율은 각각 30.4%와 21.3%로 동절기 온실시료의 배양에서 높게 나타났다. 또한 정상상태에서 자란 모식물체와 신장기에 한발 스트레스를 받은 모식물체의 캘러스 유기율은 각각 19.2%와 7.2%로서 약유래 모식물체의 생육환경에 따라 큰 차이를 보였다. 약 채취 시기는 외형적인 식물체의 엽이간장이 5～10 cm 정도로 지엽 다음 엽의 엽이와 엽초 내 이삭의 가장 불룩한 중앙부위가 일치하는 시기(출수전 3～4일)를 기준으로 약을 선별하여 치상 하는 것이 유기효율이 높았다. 전처리는 직경 10 cm의 롤(roll) 비닐봉지에 5～10 개체의 이삭을 밀봉하여 4℃에서 3주간 실시하는 것이 효과적이었으며, 관행 페트리디쉬 보관에 비하여 약 6배 정도의 노력절감효과를 보였다. 전처리 기간 및 온도별 시료의 상태는 4℃에서 4주까지, 7℃는 2주까지, 10℃는 1주까지 신선도 유지가 가능하였고, 전처리 기간은 4℃, 3주에서 두원찹쌀보리(2조)와 새쌀보리(6조)가 각각 4.8%, 1.7%의 캘러스가 유기되어 가장 높았다.

In general, since partial pollen is derived to sporophyte, anther culture efficiency is low, and practical application that is introduced in actuality breeding technology is not many. This study was carried out to improve regeneration of green plants through some culture environments contol in anther culture of naked brley. Among the factors related with plant regeneration, medium was effective in component containing L-glutamine 256 mg/L, L-proline 250 mg/L, IAA 1 mg/L and BAP 2 mg/L controlled in addition sucrose 30 g/L or maltose and sucrose mixed each 30 g/L to increase both plant regeneration and green plant regeneration rate. Also, adequate content of CuSO4 was the best at 1.25 mg/L (fifty-fold), it was tendency to decrease albino production rate. Starvation was effective at 30℃, 7 days in case of Saessalbori for plant regeneration and Dooweonchapssalbori at 30℃, 10 days with increasing green plant regeneration against albino. After plant regeneration, under acclimation by hydroponics, roots and shoots were well developed at 20℃, light control as 2,000～5,000 Lux and photoperiodic reaction by 14/10 as dark/light in the early growth stage. In acclimation method, plants acclimated in the modified Yoshida solution filled-vermiculite in GP pot is superior (100%), in which was controlled by temperature 20℃, pH 6.0 and relative humid 90% over, especially, after transplanting in pot growth of root, sheath and leaf are more active in 20℃ and 5,000 Lux control. For Vernalization, plants derived from anther culture of F1 naked barley was different from their parents with normal heading plant even about 50% in the F1 hybrids whose vernalization was strong, whereas the rest of plants derived from anther culture formed rosette, showing that normal growth were impossible.

A number of field experiments were conducted to assess the role of combined application of nitrogen and sulfur to increase the seed and oil yield of nonnodulating soybean (Glycine max (L) Merr.) cv. PK-416 (V1) and cv. PK-1024 (V2) . Six combinations of N and S in three replicates each were used for this purpose i.e. 0~;S+23.5kg~;N~;ha-1(T1);~;0~;S+23.5+20kg~;N ~;ha-1(T2);~;40~;S+23.5kg~;N~;ha-1(T3);~;40~;S+23.5+20kg~;N~;ha-1(T4);~;20+20~;S+23.5kg~;N~;ha-1(T5);~;20+20~;S+23.5+20kg~;N~;hal(T6) . Nitrate reductase (NR) and ATP-sulphurylase activities in the leaves were measured at various growth stages as the two enzymes catalyze the rate limiting steps of the assimilatory pathways of nitrate and sulphate, respectively. The activities of these enzymes were strongly correlated with seed yield. The higher seed, oil and protein yields were achieved with the treatment T6 in both the cultivars due to optimization of NR activity and ATP-sulphurylase activity, as these parameters were influenced by N and S assimilation. Any variation from this combination was observed to decrease the activity of these enzymes resulting in reductions in the seed, oil and protein yield of soybean.

Potassium (K) distribution in rice (Oryza sativa L.) root was studied by confocal laser microscopy, using potassium sensitive fluorescent dye potassium-binding benzofuran isophthalate (PBFI). Significantly high intensity of K-specific fluorescence was detected at the root cap region followed by meristematic and basal regions. A negligible or fainted fluorescence was observed at the root hairs area. These results suggest that K is heavily distributed in the apical area of rice root, which may be required in higher concentration for division and extension of cells, as it is the rapidly growing region of the root, moreover, may also be involved in water uptake by creating osmotic gradient across membranes.

Each parent, P1 and P2, ten F1 hybrids among 5 parents, eight F2, B1 (F1 × P1), and B2 (F1 × P2were evaluated for spikelet fertility related to cold tolerance in cold-water irrigated plot. Heterosis for spikelet fertility varied from8.6% to 60.5% with a m

A field experiment was conducted to assess the growth characteristics, seed and oil yield of two cultivars of soybean (G max (L.) Merr.) cv. PK-416 (V1 ) and cv. PK-1024 (V2 ) in relation to sulphur and nitrogen nutrition. Six combinations (T1-T6 ) of two levels of sulphur (0 and 40 kg ha-1 ) and two levels of nitrogen (23.5 and 43.5 kg ha-1 ) were applied to the two soybean cultivars as nutrients. Results indicated significant effect of sulphur and nitrogen, when applied together, on the growth characteristics, yield components, and seed and oil yield. Maximum response was observed with treatment T6 (having 40 kg S and 43.5 kg N ha-1 ). Seed and Oil yields were increased 90 and 102~% in V1 > and 104 and 123~% in V2 , respectively as compared to the control i.e. T1 (having 0 kg S and 23.5 kg N ha-1 ). Positive responses of S and N interaction on leaf area index, leaf area duration, crop growth rate and biomass production were also observed. The results obtained in these experiments clearly suggest that balanced and judicious application of nitrogen and sulphur can improve both seed and oil yield of soybean cultivars by enhancing their growth.