• KOREAN JOURNAL OF CROP SCIENCE
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• v.1 no.1
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• pp.42-45
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• 1963

In a plant breeding program, an efficient selection of desired characters in a population is important. Generally, many agronomic characters in a given population are determined by polygenes and quantitatively inherited. In practice, the genetic relationship between two observed characters which are undoubtedly subjected to the environmental influence is difficult to identify. In recent years, many workers have attempted to understant the genetic relationship between characters in terms of genotypic correlation, and the knowledge thus gained should furnish many important and useful information for the planning of breeding, selection, and interpretation of the result. The genotypic correlation is the result of pleiotropy, linkage of genes(2, 3, 5, 6, 8) and natural or artificial selection(4). The purposes of this study were to estimate genotyric and phenotypic correlations between all possible pairs of nine characters. and to seek certain characters which may be useful as indicators of certain important agronomic characters. Weber and Moorthy(10), Johnson et al. (5) and Sheth(7) found that in general, the genotypic correlations were higher than the phenotypic correlations. Weiss et al. (11) obtained significant positive correlations between maturity and oil content, maturity and low protein content, and high protein content and low oil content. Weber and Moorthy(10) reported the positive genotypic correlations between flowering and maturity, yield and maturity, yield and plant height, yield and seed weight, and negative genotypic correlations between maturity and oil content, and oil content and seed weight. Johnson et al. (5) studied the genotypic and phenotypic correlations among 24 characters and concluded that selection based entirely on a long fruiting period, lateness, heavy seed, low protein, high oil and resistance to lodging would be effective in increasing yield. Sheth(7) found the following positive associations among characters; height and maturity, yield and lodging, low protein content and high oil content, and yield and low protein content. Hanson et al.(1) also reported high negative correlation between seed yield and protein content.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.2
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• pp.163-168
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• 2006

Improvement of crop yield can be achieved through understanding genetic variation in reproductive characters and its impact on yield components. The present study was performed to evaluate genetic diversity for reproductive growth characters in exotic germplasm resources and to determine the relationships between developmental and growth periods with yield and yield components in soybean cultivar groups. For phenotypic evaluation such as reproductive and agronomic traits, a total of 80 indigenous and exotic soybean cultivars collected from four different geographical regions (China, Japan, Korea, and Vietnam) were grown from May to November of 2003 at the Seoul National University Farm, Suwon, Korea ($127^{\circ}02'E$ longitude, $37^{\circ}26'N$ latitude). Most of all the characters exhibited wide range of phenotypic variation, of which pod number, seed number, and plant yield showed greater range as compared to other characters. Korean cultivar groups showed greater diversity than the other cultivar groups in seven characters. Correlation analysis showed that days to flowering (DTF) and days to maturity (DTM) had close association with agronomic traits as well as yield and yield components. Both DTF and DTM had positive correlation with the other characters except one hundred seed weight. Stepwise multiple linear regression revealed that seed and pod number were identified as being significant for plant yield. The results in this study indicated wide variation in agronomic traits including DTF and DTM, suggesting the valuable genetic resources in a soybean breeding program.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.2
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• pp.39-46
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• 1983

In order to obtain the basic information for the most successful breeding of Burley tobacco, these studies were performed on the correlations among agronomic characters and on the heterosis and combining ability in $F_1$ generation. Heterosis ratio was highly variable in different $F_1$ combinations. Positive heterosis was observed in all characters except days to flowering and yield showed the highest heterosis ratio. As the results of analysis of dialled table, the general combining ability (GCA) in all characters was shown to be significant . All characters except the number of leaves in the specific combining ability (SCA) were significant, Variety, L8, contributed negative GCA for all characters. Burley 21, ky 10 and ky 14 contributed negative GCA for leaf width, quality and yield, respectively. Hybrid of ky 10 x ky 14 showed negative SCA and hybrids of ky I0x L8 and ky 14 x L8 showed positive SCA for all characters. There were significant correlations between yield and number of leaves, leaf length, leaf width or leaf area. Correlation between yield and days to flowering was non- significant .

• The Plant Pathology Journal
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• v.18 no.2
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• pp.68-73
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• 2002

The influence of fungicidal spray was assessed on powdery mildew epidemics caused by Erysiphe polygoni D.C. and on yield-attributing characters of mungbean [Vigna radiata (L.) Wilczek]. Mildew attack adversely affected the yield-attributing characters of mungbean and exhibited negative significant correlation with pod length (-0.57), pods/plant (-0.74), pod weight (-0.68), 100 seeds weight (-0.69), 100 seeds swell weight (-0.59), and seed germination (-0.71). These characters had direct or indirect effects on grain yield, which was also adversely affected due to mildew attack (-0.89). Powdery mildew was significantly retarded due to the single spray of carbendazim (0.05%) at 30-day-old crop, where the apparent rate of infection (r) was minimum at 0.0095/ unit/day and with low (11.44%) powdery mildew intensity. Other fungicides like tridemorph (0.075%) and penconazole (0.05%) were equally effective against the mildew disease where the disease intensity was less than 20% and the values of r were 0.0134 and 0.039/unit/day respectively, as compared with the control at 0.267/unit/day. Fungicide spray influenced the yield-attributing characters besides controlling the disease. Such effects were more pronounced in carbendazim (0.05%)-treated plots due to its phytotonic nature where pod length (7.59cm), pods/plant (29.75), pod weight (8.16 g), 100 grain weight (3.94 g), and swell weight of 100 seed (9.49 g) were maximum resulting to the highest yield (480 kg/ha) as compared with that of control (224 kg/ha). Spray of carbendazim also improved seed germination (74.5%). Spray of other fungicides like carbendazim with copper oxychloride in 1:1 ratio, tridemorph (0.075%), and penconazole (0.05%) was equally effective against powdery mildew of mungbean. These fungicides also exhibited positive effects on yield-attributing characters of the crop and finally increased yield. These systemic fungicides were more effective in controlling powdery mildew disease of V. radiata in the rainy season compared with wettable sulphur.

• Journal of the Korean Society of Tobacco Science
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• v.9 no.1
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• pp.45-55
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• 1987

For some basic information in tobacco breeding, the modes of inheritance and heritabilities for the twelve agronomic and chemical characters were estimated in the study of eight varieties partial diallel set. Additive gene actions were significant for all characters except total nitrogen content and dominance gene effects were also significant for all characters. Yield, number of leaves per plant, leaf length and leaf shape index were inherited as partial dominance, and overdominance was detected for plant height, stem diameter, internode length, total alkaloid, total nitrogen and total sugar content. Dominant gene showed increasing effects in yield, plant height, stem diameter, internode length, leaf width and total sugar content, but showed decreasing effects in the other characters. The broad heritability was very high for all characters. and the narrow heritability was high in days to flower and yield, but low in internode length, total alkaloid, total nitrogen and total sugar content.

• International Journal of Industrial Entomology and Biomaterials
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• v.13 no.1
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• pp.15-22
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• 2006

An experiment was conducted to study the efficiency of cyanobacterial biofertilizer (CBB) with chemical (NPK) fertilizer on quantitative and qualitative characters of mulberry variety Kanva-2. Their influences on silkworm growth and cocoon characters were also studied. Ten different CBB and NPK fertilizer treatments were given to 5000 plants of established mulberry garden. Treatments were of four types viz., (i) T1 to T7: single and combination dose of CBB+50% NPK (ii) T8: combination dose of CBB + 25%NPK, (iii) T9: CBB only and (iv) T10: control-l00% NPK. Soil pH decreased and nutrients status increased in CBB (T1- T9) treated plots. Average of ten crops data on quantitative traits revealed that T7 (CBB [N. muscorum (1.0 g), A. variahilis (1.0) and S. millei (1.0 g)] + 50% NPK) was very effective in improving growth parameters. Leaf yield was also found high in treatment T7 (32.12 tons/ha/yr.) followed by T10 (31.17 tons/ha/yr.) and T8 (27.67 tons/ha/yr.). Leaf quality characters were found high in T7 and low in T9. Most of the quality traits in T7 are on par with control no. The results revealed that reduction in the dose of chemical fertilizers in T7 did not affect the leaf yield and leaf quality traits of mulberry. This clearly indicates that the efficiency of CBB (T7) provides nitrogen, increases essential nutrients available in soil, maintain soil pH and supply growth substances required for the improvement of leaf yield and leaf quality of mulberry. Bioassay study also revealed no significant difference in silkworm growth and cocoon characters between treatments T7 and T10. Economics calculated revealed that T7 is highly economical and beneficial over T10 by gaining an amount of Rs. 660/-/acre/crop. Thus, treatment T7 containing N. muscorum (1.0 g), A. variahilis (1.0 g) and S. millei (1.0 g) + 50% NPK fertilizers can be recommended to sericulturists mainly to reduce the use of NPK fertilizers, by saving 50% of its cost and to improve soil fertility conditions, which in turn improves leaf yield and quality of mulberry.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.2
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• pp.177-182
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• 1999

This research was carried out in a farm situated in Malkara District of Tekirdag Province (Turkey) in 1994-95, and the effect of genotype and environmental conditions on some characters and variations of these characters in terms of silage yield in 8 dent corn varieties were determined. The results of this research showed that leaf weight, stem diameter, and silage yield had a low broad sense heritability while the number of leaves per plant had a high heritability. Yield performance of varieties varied to a significant degree because of variations in rainfall rate during the growing periods. Leaf number, silage yield, leaf weight, stem diameter, plant height and ear weight varied between 13.33-17.33 number, 8,443-11,114 ton/hec, 152.8-244.2 g, 2,615-2,965 cm, 216.5-252.5 g and 176.2-285.8 g, respectively.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.2
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• pp.181-195
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• 1989

The study was conducted to obtain the genetic informations for some useful characters in tobacco breeding. The eight parents and a set of 28 crosses of F1's and F2's were used as materials, and planted on two different cultivated systems, i. e., oriental's and burley systems, during 1986-1988 at taegu Experiment Station, Korea Ginseng & Tobacco Research Institute. The observed characters were six agronomic characters which were plant height, number of leaves per plant, leaf length, leaf width, days to flowering, yield and five chemical components, nicotine, total nitrogen, protein nitrogen, total volatile base and pet, ether extract. The results obtaining are summarized as follows: 1. The higher heritabilities were found for days to flowering yield and nicotine in both generations, but values for number of leaves per plant, leaf length, total nitrogen and protein nitrogen were lower than other characters. 2. Genotypic correlation coefficients among all pairs of characters were slightly higher than the corresponding phenotypic correlations in F1's and F2's on two different cultivated systems. The relationship between leaf length and leaf width was the positive correlation, but that between number of leaves per plant and leaf width was negative. 3. From the genotypic correlations between yield and other characters, a conclusion that the yield was highly correlated with plant height, leaf length, leaf width and days to flowering was given. 4. Quality was positively correlated with number of leaves per plant and nicotine, but negatively with the other agronomic characters and chemical components.

• Plant Resources
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• v.5 no.2
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• pp.118-123
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• 2002

In order to obtain the genetic information on the quantitative characters of black seeded soybeans, which would be needed to improve selection efficiency for breeding high yielding genotype, 45 varieties of black seeded soybeans collected in Chonnam, Korea were grown and variations of several important characters were observed. Heritability of each observed character, phenotypic and genotypic correlations among the characters and contribution of each yield component on grain yield through path coefficient analysis were estimated. Both number of pods per plant and 100-seed weight showed not only high heritability but also highly significant phenotypic and genotypic correlation with seed yield, and hence it was desirable to select plants with more number of pods per plant and higher 100-seed weight than raise seed yield of black seeded soybeans collected in Chonnam. In addition, number of pods per and 100-seed weight were proved to be the most influential variables on the viability of seed yield by path coefficient analysis. Since these showed the high heritability of number of pods per plant, selection of plants with higher 100-seed weight would be more efficient for breeding high yielding genotype.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.151-156
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• 2002

The heritability of sink-source characters was estimated by regression coefficient between F$_2$ and F$_{5}$ in two crosses of IR 66738-118-1-2/Gayabyeo and the Ilpumbyeo/YR 15965 Acp 33. In order to get the some basic information for breeding of high yielding rice, genetic resources of new plant type with low tiller and heavy panicle were used. Most of the sink and source characters in Ilpumbyeo/YR 15965 Acp 33 cross showed high heritability over than 0.224. But the specific leaf area and sink-source ratio displayed low heritability being 0.009 and 0.013, respectively. Heritability of all sink and source characters in IR 66738-118-1-2/Gayabyeo cross ranged from 0.115 to 0.247. Correlation coefficient between yield and yield components in both combination were in the ranged between 0.001 and 0.247. But correlations among the yield components were not significant. Correlations between the yield and sink-source characters in both combinations were also highly significant. Particularly, correlation between the grain tiling ratio and most of the sink-source characters in IR 66738-118-1-2/Gayabyeo cross were not significant. In Ilpumbyeo/YR 15965 Acp 33 cross, correlations between grain filling ratio and source characters were positively significant. but sink characters (sink capacity and sink-source ratio, etc) were negatively significant.