Early predictions of crop yields call provide information to producers to take advantages of opportunities into market places, to assess national food security, and to provide early food shortage warning. The objectives of this study were to identify the most useful parameters for estimating yields and to compare two model selection methods for finding the 'best' model developed by multiple linear regression. This research was conducted in two 65ha corn/soybean rotation fields located in east central South Dakota. Data used to develop models were small temporal variability information (STVI: elevation, apparent electrical conductivity (ECa) , slope), large temporal variability information (LTVI : inorganic N, Olsen P, soil moisture), and remote sensing information (green, red, and NIR bands and normalized difference vegetation index (NDVI), green normalized difference vegetation index (GDVI)). Second order Akaike's Information Criterion (AICc) and Stepwise multiple regression were used to develop the best-fitting equations in each system (information groups). The models with δi~leq2 were selected and 22 and 37 models were selected at Moody and Brookings, respectively. Based on the results, the most useful variables to estimate corn yield were different in each field. Elevation and ECa were consistently the most useful variables in both fields and most of the systems. Model selection was different in each field. Different number of variables were selected in different fields. These results might be contributed to different landscapes and management histories of the study fields. The most common variables selected by AICc and Stepwise were different. In validation, Stepwise was slightly better than AICc at Moody and at Brookings AICc was slightly better than Stepwise. Results suggest that the Alec approach can be used to identify the most useful information and select the 'best' yield models for production fields.

This study was conducted to investigate the effect of activated carbon on leaf and stem production of Agastache rugosa as affected by different amounts of activated carbon. The results obtained are summarized as follows. Growth characteristics including plant height and leaf length were the highest when activated carbon added with 10%, suggesting that optimum amount of activated carbon was ranged from 10 to 20%. Growth and enlargement of the root were improved by 10% AC. Activated carbon can be utilized as a soil conditioner in agricultural crop areas.

This study was conducted to determine feasibility of production system of Perilla frutescens leaf-stem by fertilizing of Sta-Green in pots. Germination rate of Perilla frutescens seeds collected in 2002 was 7%, also germination rate of seeds collected in 2003 was 62%, while germination rate of seeds collected in 2004 was above 93%. Seed germination rate of Perilla frutescens collected in 2004 were higher than seed gathering in 2002. Especially, plant growth and yield of Perilla frutescens grown in pot(The pots was filled with soil mixtures of Sta-Green and Peat Moss mixed with 40:60 ratio.) was the highest. These results indicate that leaf and stem production of Perilla frutescens can be improved by fertilizing of Sta-Green in pots.

A full-length cDNA (PPrx1) encoding peroxidase has been isolated and its nucleotide sequence determined from flower bud in ginseng plant (Panax ginseng). A PPrx1 cDNA is 1192 nucleotides long and has an open reading frame of 1062 bp with a deduced amino acid sequence of 354 residues (pI 7.53). The deduced amino acid sequence of PPrx1 matched to the previously reported peroxidase protein genes. The PPrx1 showed a high similarity with the 64% identity with peroxidase of N. tabacum (AAK52084). In the phylogenetic analysis based on the amino acid residues, the PPrx1 was closer with peroxidase of G. max (AAD37376).

Ribosomal protein complex with ribosomal RNA to form the subunits of the ribosome serve essential functions in protein synthesis. A full-length cDNA (PRPS4) encoding ribosomal protein S4 has been isolated and its nucleotide sequence determined in ginseng plant (Panax ginseng). A PRPS4 cDNA is 1105 nucleotides long and has an open reading frame of 792 bp with a deduced amino acid sequence of 264 residues (pI 10.67). The deduced amino acid sequence of PRPS4 matched to the previously reported ribosomal protein S4 genes. Their degree of amino acid identity ranged from 68 to 92%. Phylogenetic analysis based on the amino acid residues showed that the PRPS4 grouped with ribosomal protein S4 of S. tuberosum (CAA54095).

Mass selection (MS) is an efficient selection method to directly improve highly heritable traits. In the present study, two cycles of MS for ear length were conducted on two sweet corn populations, BC2-l0 and BC1-10~timesSyn-II after introgression of exotic germplasm. The improved populations generated from these selections were evaluated in comparison with the base populations at two locations, to determine the genetic gains and performance of the improved populations. The two base populations showed varied average realized responses to MS. In BC2-l0 derived population, the realized responses were 9.1~% in BC2-l0 C1 and 1.2~% in BC2-l0 C2, whereas inBC1-10~timesSyn-II derived population, the realized responses were 5.6~% in BC1-10~timesSyn-II C1 and 2.9~% in BC1-10~timesSyn-II C2. All the improved populations showed longer ears than their respective base populations and the check varieties. Ear length, which was used as the selection criterion in this study, showed high broad-sense heritability in the BC2-l0 and BC1-10~timesSyn-II derived populations, while fresh ear yield revealed low heritability, indicating that selection for ear length in these populations would be more effective than direct selection for yield. Results of this study indicate that MS conducted on BC2­10 and BC1-10~timesSyn-II had significantly increased ear length and fresh ear yield in both populations. The improved populations obtained would serve as better germplasm sources and further selection in these populations could offer better responses.

Proper choice of source populations contributes to the ultimate success of selection for genetic improvement. The source population should possess the most desirable alleles at as many loci as possible for intra population improvement. Such desirable alleles can be intensified by introgression of exotic germ plasm into locally adapted ones through hybridization followed by selection. The objectives of this study were to determine the mean performance, genetic variability (~sigma2G) and heritability of fresh ear yield and other important traits within two sweet corn source populations, BC1-10~timesSyn-II and BC2-10. One hundred selfed progenies from each of the two source populations were evaluated in a 10~times10 lattice design, at the Institute of Bioscience (IBS) Farm, University of Putra Malaysia (UPM) following the recommended cultural practices. Significant differences among selfed progenies within BC1-10~timesSyn-II were observed for all traits, while differences among selfed progenies within BC2-10 were noted for fresh ear yield, ear length, ear diameter, number of kernels per row, ear height, days to tasseling and days to silking. Progenies developed from BC1-10~timesSyn-II population had higher estimates of ~sigma2G than did progenies from BC2-10 population for number of kernel rows per ear, total soluble solids, plant height, days to tasseling and days to silking, showing that selection to improve these traits would be more effective in selfed progenies of BC1-10~timesSyn-II than that in BC2-10. On the other hand, progenies developed from BC2-10 population had higher estimates of ~sigma2G for ear length, ear diameter and ear height, indicating that progenies from this population would have better genetic gain than BC1-10~timesSyn-II . Comparable estimates of genetic variance were found for fresh ear yield, and number of kernels per row, indicating that genetic improvement of the two source populations is expected to produce similar genetic gains for these two traits. Therefore, selfed progenies developed from both source populations could be used to improve the two populations for various traits and thereby develop superior genotypes for immediate use in the production system.

A cDNA, PSOD1, encoding cytosolic copper/zinc superoxide dismutase (CuZn-SOD) was cloned and characterized from a full length cDNA library prepared from Populus alba×Populus glandulosa cultured in vitro. A PSOD1, is 725 nucleotides long and has an open reading frame of 459 bp with 152 amino acid residues (pI 5.43). The deduced amino acid sequence of PSOD1 perfect matched to the previously reported CuZn-SOD (CAC33845.1). Consensus amino acid residues (His-45, -47, -62, -70, -79, -119) were involved in Cu-, Cu/Zn-, and Zn- binding ligands. The deduced amino acid sequence of PSOD1 exhibited the high level of similarity from 100 to 85% among previously registered SOD genes. The expression of PSOD1 in poplar increased at the 1 mM H2O2 and drought stress during 30 min and 60 min, but the ozone treated poplar increased at 30 min in the early time and then decreased at 60 min.

A type 3 metallothionein cDNA (PMT3a) from ozone-treated Populus alba×Populus glandulosa cDNA library has been isolated and characterized. A PMT3a cDNA is 459 nucleotides long and has an open reading frame of 201 bp with a deduced amino acid sequence of 66 residues (pI 4.94). The deduced amino acid sequence of PMT3a matched to the previously reported metallothionein genes. The deduced amino acid sequence of PMT3a showed the 86% identity with P. balsamifera ×P. deltoides. Expression of PMT3a by the RT-PCR was increased 60 min than 30 min after drought treatment. The ozone treated poplar increased at 30 min in the early time and then decreased at 60 min.

To find out the optimum mixture ratio of ammonium and nitrate on rice plant, 4 rice varieties were examined during 14days after transplanting in hydroponics with the different ratio of ammonium to nitrate(100 : 0, 75: 25,50: 50, 25: 75 and 0: 100). The highest N uptake from solution and the maximum plant dry weight were 60~~70~% ammonium and 30~~40~% nitrate mixture treatment both in Japonica and Tongil type rice plants. And with the same varieties N-uptake and N use-efficiency were compared between 10.0 mM and 1.0 mM nitrogen using 70~% ammonium and 30~% nitrate for 24 days after transplanting. Rice plants absorbed more nitrogen(131~~145~%) in 10.0mM than 1.0mM treatment but accumulated N in rice plants were almost the same in both treatment. Among the tested rice cultivars, dry matter production and total accumulative nitrogen in rice plants were much high in Tongil type than japonica type rice cultivars. N-recovery ratios of rice plants from uptake N were 90.8-99.0~% in low concentration N solution(1.0 mM), but 69.4-81.7~% were observed in high concentration N solution(10.0 mM). It means that suppling low concentration N steadily will be better to prevent loss of N without reducing of growth in rice plants.