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Newly synthesized polycarbonate diols containing hindered urea (PCD-HUs) were employed to modify the scratch-healing properties of conventional two-component clearcoats. To elucidate their contributions to the crosslinking properties of the coatings under conventional thermal curing (150°C), the real-time rheological properties of the clearcoat mixtures were measured using a rotational rheometer in the small-amplitude oscillatory shear mode. A dynamic mechanical analysis was carried out to compare the thermomechanical properties of the cured clearcoat free films. PCD-HU, a key component for the tuning of the scratch-healing, was further identified by analyzing the clearcoat layer cured over a phosphated metal substrate with undercoats such as primer and basecoat as a precoated metal (PCM) sheet. Elastic recovery and scratch profiles of the outermost clearcoat layer in the PCM sheet were acquired through nano-indentation and nano-scratch tests by gradually increasing the quantitative normal force. Finally, the healing patterns of the scratches on various clearcoat layers at a certain normal force were visualized by three-dimensional and one-dimensional cross-cut images using atomic force microscopy under specified temperature and healing time conditions. The surface durability provided by the PCD-HU in the clearcoat layer was confirmed by repeated scratching and healing tests on the same surface positions. Therefore, the coating layer containing HU, which possessed similar surface mechanical properties to those of conventional references, exhibited better scratch-healing performance.

Regarding carotenoids content, the genetic basis, heritability and combining ability in six red pepper inbred lines were investigated using full diallel crosses. Both additive and non-additive gene actions govern inheritance of carotenoids content. The mean square of array through variance and covariance analysis (Wr-Vr) was insignificant, which suggest that inbred lines involved in diallel cross may have no epistatic effects. The Vr/Wr graph revealed the influence of partial dominant gene action towards low carotenoids content and the absence of non-allelic interaction. The H2 component was smaller than the H1 and the [H2/4H1] component was 0.187 less than 0.25, indicating unequal proportion of positive and negative alleles in the parents. The estimates of broad and narrow sense heritability for carotenoids content were 0.956 and 0.832, respectively. The variance of general combining ability (GCA) was relatively higher than that of specific combining ability (SCA), which implied that the additive gene effects were predominant as compared to both dominant and epistatic effects for the accumulation of carotenoids in this genetic population. The values of GCA of ``62024L1`` and ``62067L2`` were higher than those of the other parents. These 2 inbred lines, therefore, can be considered as useful breeding materials to enhance fruit carotenoids content in other red pepper varieties.

Field experiments were conducted to determine the effect of sulfur (S) and Nitrogen (N) on nitrate reductase (NR) and ATP-sulfurylase activities in groundnut cultivars (Arachis hypogea L. cv. Ambar and Kaushal). Two combinations of S (in kg ha-1): OS (-S) and 20S (+S) were used with 20 kg ha-1 N. The application of S enhanced the NR and ATP-sulfurylase activities in both the cultivars at all the growth stages. The application of S also increased soluble protein and chlorophyll content in the all growth stages of both the cultivars. NR and ATP-sulfurylase 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 sulfate, respectively.

Plant mitochondrial genomes have complex configurations resulting from the multipartite structures and highly rearranged substoichiometric molecules created by repetitive sequences. To expedite the reliable classification of the diverse radish (Raphanus sativus L.) cytoplasmic types, we have developed consistent molecular markers within their complex mitochondrial genomes. orf138, a gene responsible for Ogura male-sterility, was detected in normal cultivars in the form of low-copy-number substoichiometric molecules. In addition to the dominant orf138-atp8 Ogura mitochondrial DNA (mtDNA) organization, three novel substoichiometric organizations linked to the atp8 gene were identified in this study. PCR amplification profiles of seven atp8- and atp6-linked sequences were divided into three groups. Interestingly, the normal cytoplasm type, which had previously been considered a single group, showed two patterns by PCR amplification. The most prominent difference between the two normal mtDNAs was size variation within four short-repeat sequences linked to the atp6 gene. This variation appeared to be the result of a double crossover, mediated by these homologous, short-repeat sequences. Specific PCR amplification profiles reflecting the stoichiometry of different mtDNA fragments were conserved within cultivars and across generations. Therefore, the specific sequences detected in these profiles were used as molecular markers for the classification of diverse radish germplasm. Using this classification system, a total of 90 radish cultivars, or accessions, were successfully assigned to three different mitotypes.

To find fertile garlic clones to be used in the cross breeding program, 213 accessions were subjected to cytological study at meiosis I. Most accessions (185 clones) showed abnormal chromosome configurations of ring of four, six or eight, which are ascribed to single or multiple translocations. Two clones showed asynaptic behavior forming 16 univalents from zygotene to metaphase I, and 26 clones revealed regular chromosome paring of 8 bivalents. Only six of 26 clones showing normal meiosis produced viable pollen grains, while the rest were male sterile. From the segregation of crosses between male sterile and fertile clones, the male sterility is presumed to be governed by single recessive gene. Hybrid plants between the fertile clones appeared, in general, intermediate of the parents in field performance.

Six F1's involving 6 multiple genetic marker stocks and a common inbred parent (PU812) were cultured to study the genotypic effect on regeneration ability and frequency of somaclonal variation in R0 for the known heterozygous marker genes. Leaf discs 7 mm in diameter were excised from young fully expanded leaves of 6-7 week old plants, and cultured on MS medium supplemented with cytokinins (Kinetin, Benzyladenine) and IAA. With few exceptions, the parents and F1's responded similarly to different hormone combinations. The beat hormone combinations for shoot formation were 4 mg/l Kinetin + 0.5 mg/l IAA and 2.3 mg/l BA + 0-0.18 mg/l IAA.Only 2 of the 6 multiple marker stocks and the common inbred parent (PU812) were successfully regenerated. Four of the six hybrids between PU812 and the multiple markers were readily regenerated, whereas 2 hybrids failed to regenerate with several different hormonal combinations. No mutations have been observed for the known heterozygous markers in 76 R0 tissue culture regenerants.

The tangerine-virescent (tv) mutation was reported as a single gene somaclonal variant from tissue culture (Evans and Sharp 1963). A replicated field trial was conducted to characterize variation and stability in the phenotype of this tv somaclone and to compare it with the inbred parent from which it was reportedly derived.Heritability and stability of the tv somaclonal variant was measured by comparing R3 end R4 lines of sexual progenies of the original tv variant and with its sexually derived inbred parent UC82B. Several additional variants were observed in these tv lines, including fruit shape, days to first flower, fruit weight, yield, plant type, and fertility. Eight sterile or semi-sterile plants were discovered in 6 of 39 R4 lines. Our results suggest that multiple genetic changes have occurred in the tv somaclonal variant and while the original tv mutant is stably inherited, additional genetic abnormalities occur following sexual reproduction.

Heterozygous multiple marker genetic stocks were synthesized by crossing three multiple genetic marker stocks to a common inbred parent PU812. The four parents and 3 F1's were cultured to obtain regenerants from leaf discs. Fifty four regenerants were derived from 3 F1's and 12 from the 4 parents, Among the regenerants, 16 plants were identified as tetraploid (24.2%); low fertility was usually associated with tetraploidy, however there were a few exceptions.Selfed seeds, identified by cluster number, were harvested from sexual F1's and R0 plants for F2 progeny tests for the known marker genes. While there were no abnormal segregations for marker genes in the sexual progenies, 13 of 46 progenies from tissue culture derived regenerants showed significant deviations from expected normal segregations for a number of markers. Two of the abnormal progenies were identified as tetraploids by root-tip examinations; segregation ratios fit duplex random chromatid segregation for gene a on chromosome 11 and random chromosome segregation for gene c on chromosome 6. The cams of abnormal segregations in other progenies remain unknown. Results suggest that unknown genetic events arising during tissue culture may distort segregations for marker genes in the subsequent sexual progeny of tissue culture regenerants.