• Journal of the Korean Society of Tobacco Science
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• v.22 no.1
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• pp.31-38
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• 2000

Seven flue-cured tobacco(Nicotiana tabacum) varieties and their 21 progenies in Fl and F2 generation, half diallel crosses(no reciprocal), were tested for the degree of heterosis and combining abilities in sucker producing character according to topping and suckering treatment. Significant difference in number and weight of sucker was observed among seven cultivars. The values of general combining ability(GCA) were greater than those of specific combining ability(SCA) in weight and number of sucker in F$_1$ generation. In topping and suckering plot, Cocker 86, McNair 944, and Va 115 revealed the significant negative GCA effects for number and weight of sucker, but By 104 and Speight G-28 did positive GCA. Without topping and suckering, GCA effects for sucker weight in Cocker 139 and Cocker 86 were negative and those for sucker number in Va. 115 were also negative. Negative SCA values in sucker weight could be observed in F$_1$ generation of Cocker 86 X BY 104 and Speiht G-28 X Cocker 86, in F$_2$ of Hicks $\times$ Speight G-28 and McNair 944 $\times$ BY 104 in topping and suckering plot. SCA in F$_1$ of McNair 944 X Cocker 86 and Speight G-28 X Cocker 139 was negative without topping and suckering. The value of heterosis in sucker producing character of F$_1$ hybrids was positive

• Journal of the Korean Society of Tobacco Science
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• v.23 no.1
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• pp.5-11
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• 2001

Experiments were conducted to evaluated the sucker control efficiency of several suckercides and their combinations for flue-cured tobacco in Korea. In 1999, Flumetralin(Prime+, P+), Butralin(B), Fatty alcohol(FA, n-decanol 85%), pottasium salt of maleic hydrazide(MH), tank mix of MH with P+ (MH·P+), and another tank mix of MH with FA(MH·FA) were applied after topping, respectively, then sucker number and sucker dry weight were investigated on the 30th and 50th day from treatment. Sucker number and dry weight were significantly lowered by P+, B, FA and MH·P+ applications compared with those of MH and MH·FA for both investigated periods. A significant reduction in sucker number and dry weight was observed in P+, B, and MH·P+ applications. FA treatment was not so much effective in sucker control as P+. In 1999 and 2000, several suckercides and tank mixes of their combinations were applied first at button stage and second after topping, respectively, to compare the effects of sucker control on yield, price index and chemical components of cured leaves. Compared to the standard method of FA 30x at button stage followed by MH40x application after topping(FA 30x + MH 40x), sucker number and dry weight decreased by [FA 30x (or P+ 1%] or [FA 30x(or B 1.5%) + MH 60x·B 1.5%] treatments, even at reduced MH levels. But yield, price index and chemical components of cured leaves were not differed among treatments.

• Journal of the Korean Society of Tobacco Science
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• v.25 no.2
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• pp.154-159
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• 2003

Using sucker agents for tobacco can lead some advantages including saving labor, increasing yield and reducing the spread of diseases. At present, the sucker control agents used in China mainly depended on importing. The agents includes two groups, systemics (Maleic hydrazide: MH, etc) and partial systemics (Butralin, Flumetralin, Pendimethalin, etc). Now, Pendimethalin(a.i. 33%, wp) was used extensively all over the tobacco field in China. Sucker control agents will also be used for tobacco production in China. Because of the high price of the imported agents, China has studied on the domestic production of tobacco sucker control agents and has made some progresses.

• Journal of the Korean Society of Tobacco Science
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• v.22 no.1
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• pp.39-44
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• 2000

This study was carried out to obtain the basic information about the sucker producing characteristics of certain burley tobacco varieties(Nicotiana tabacum L. var. burley) at Suwon and Chonju Experiment Station, Korea Ginseng & Tobacco Research Institute in 1999. The number and weight of suckers for 12 varieties or breeding lines were investigated three times, 45 days after transplanting for ground sucker, 10 days after topping, and 10 days after maleic hydrazide(MH) applying for upstalk sucker. KB 103 and KB 9416-1 produced less ground suckers and upstalk suckers than other entries did. KB 9210-8 produced less ground suckers and (Male sterile TC 612 x KB 108)F$_1$ also produced less upstalk suckers than other entries did. There was no differences among entries in sucker production at 10 days after MH treatment. Between the weight of total sucker and days to flower revealed the negative correlation, but not significant. The low sucker producing entries described above could be used as a parental line in the breeding program for the low sucker producing variety.

• Journal of the Korean Society of Tobacco Science
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• v.26 no.1
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• pp.7-12
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• 2004

Effect of Decyl Alcohol Emulsifiable Concentrate on sucker control and phytotoxicity to tobacco plants were tested on flue-cured tobacco and burley tobacco. There were no significant differences of sucker inhibition effect between Decyl Alcohol EC and Choline Salt of Maleic Hydrazide Soluble Concentrate(control chemical). Tobacco plants applied with Decyl Alcohol EC showed no visible symptoms of phytotoxicity and no significant differences of number of leaves, leaf length, leaf width, and stalkt height. Yields increased considerably with no difference from ones of plants treated with control chemical.

• Parasites, Hosts and Diseases
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• v.40 no.2
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• pp.67-73
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• 2002

The present study was performed to observe tegumental ultrastructure of Echinoparyphium recurvatum according to developmental stages. Worms (1, 3, 5 and 15-day old) were recovered from chicks experimentally infected with metacercariae from radix auricularia coreana. One-day old worms were elongated and ventrally concave, and covered with peg-like tegumental spines except the adjacent areas of the head crown and excretory pore. Type I sensory papillae were distributed on the lip of the oral sucker, and grouped ciliated papillae were around the oral sucker. Peg-like tegumental spines were densely distributed on the anterior surface of the ventral sucker level. The ventral sucker had an aspinous tegument and no sensory papillae. Tegumental spines on the posterior surface of the ventral sucker level were sparsely distributed and disappeared posteriorly. In 3 and 5-day old worms, the tegument around the oral sucker was aspinose and wrinkled concentrically. The ventral sucker had a wrinkled tegument and many bulbous papillae. Type I sensory papillae were distributed between the bulbous papillae. Tegumental spines were spade-shaped with a terminal tip. A total of 45 collar spines including 4 end group ones on both ventral corners was alternately arranged in 2 rows. The 15-day old worms were very stout and their tegumental spines were tongue-shaped without a terminal tip, From the above results, it is confirmed that the surface ultrastructure of E. recurvatum was generally similar to that of other echinostomatid flukes. However, some features, i.e., morphological change of tegumental spines and appearence of sensory papillae on the ventral sucker according to development, and number, shape and arrangement of collar spines, were characteristic, which may be of taxonomic and bioecological significance.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.1
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• pp.3-9
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• 1983

Due to the wide and effective use of sucker controlling chemicals, gentic studies on the suckering habits of tobacco plants have long been neglected. So, to investigate the genetic basis of suckering, crosses between "Little Dutch" and "Cuban" were made, and subsequent generations, $F_1F_2,\;BC_1,\;BC_2,$ and parents were grown on the field. Several morphological characters were measured and the relation among them were analyzed. Correlation coefficients between leaf shape and sucker leaf shape, and the number of suckers and sucker weight were 0.25 and 0.42, both sighificant at 1 % level. But negative correlation between number of suckers per plant and that of leaves was observed, though statistically not significant. Dominance was observed in the number of suckers and amount of suckers produced, and the heritability of sucker shape was calculated as high as 0.88. And two paris of genes seemed to be involved in the inheritance of sucker shape, and narrow leaf appeared as dominant in the $F_1$.inant in the $F_1$.

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.35-40
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• 1983

This study was conducted to obtain basic informations for growth regulators on occurrence of sucker in tobacco plants (Nicotiana tabacum L.). Varieties used were "hicks" and "kusaga mammoth" and growth regulators such as MH(maleic hydrazide), GA(Gibberellic acid) and BA(Benzyl adenine) were used. Immediately after topping, an application of maleic hydrazide at 900g a.i./ha completely inhibited sucker development, but sucker were developed as the rates of MH decreased, in both varieties. In nontopped tobacco plants, the similar trend as in the topped plant was observed except for no sucker development in the untreated control. Any combination of GA and BA under presence of MH had no effects on sucker development in the topped tobacco plants. However, in the nontopped plants, sucker were observed when the combined ratio of BA and GA was 10 to 1 under the presence of MH standard level. The highest no. of sucker was obtained when combined BA $10^{-5}M$ with GA $10^{-6}M$ under the presence of MH, showing higher response of hicks than that of kusaga mammoth. A single application of GA and BA in the topped plants markedly increased sucker number as GA concentrations increased showing varietal difference. GA $10^{-4}M$ increased sucker number as high as as 42% for hicks, but inhibitory effect on kusaga mammoth in comparision with the untreated control, showing very effective on hicks. BA showed the similar effect like GA. Combinations of GA and BA showed antagonistic effect on sucker development. The length of sucker was markedly promoted as the GA rates increased, and the promotive effect of sucker length by GA was not nullified by the addition of BA. But combination treatment of GA and BA mostly resulted in less dry weight than the untreated control, indicating that sucker developed from the combined treatments of GA and BA were not normal and kusaga mammoth was more affected by them.

• Parasites, Hosts and Diseases
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• v.24 no.1
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• pp.63-70
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• 1986

The tegumental ultrastructures oi Echinostoma hortense adults were observed by scanning electron microscopy. The worms of 4 weeks of age were harvested from albino rats experimentally infected with the metacercariae obtained from the loach. The results were as follows: 1. The worms were leaf-like and their anterior end portion, including oral sucker and head crown, ventrally curved to face posteriorly. The tegument of whole body was wrinkled transversely and covered with cobblestone-like cytoplasmic processes. 2. The oral sucker had roundly swollen (type I ) sensory papillae on the ventral half of its lip and mini-ciliated knob-like (type I ) sensory papillae, arranged in 2∼3 rows, on the dorsal outer surface. 3. Aspinous ventral sucker had many of type I papillae arranged in a circular band on its outer surface. The tegument around the genital opening was of similar feature to the ventral sucker, but sensory papillae were hardly found around the former. 4. Scale-like spines with broad base and round tip were distributed densely on the tegument anterior to the ventral sucker but they became sparse in posterior half of the ventral surface, finally to disappear at posterior extremity. A few number of type I papillae were observed on the ventral surface. The results suggest that the tegument of 5. hortense is similar to that of other echinostomes etapecially 5. revolutum. But the number and arrangement of collar spines, and/or the type and distribution of sensory papillae seem characteristic features of E. hortense differed from other echinostomes.

• Journal of Sericultural and Entomological Science
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• v.4
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• pp.33-39
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• 1965

Author investigated the control measure and the life cycle of the mulberry sucker, Anemoneura mori Schwarz. The results are as follows; 1. It is clear that the life cycle of mulberry sucker is one generation a year, but not obvious about the duration of pupa. 2. Even though various insecticides were used for control, they are not of a practical value during the egg stage. It is, however, believed that the mulberry sucker, when become larvae, can be controlled by spraying about 400 litres per 1 tanbo( DDVP, 1000$\times$). 3. Author recommends the control measures which you may use not only an insecticide, but also cut off branches so as to make leaf get enough sunlight and ventilation.