• Horticultural Science & Technology
• /
• v.19 no.4
• /
• pp.455-458
• /
• 2001

To screen potato clones with high resistance to hollow heart (HH) and internal brown spot (IBS), field conditions were set up to induce high frequencies of physiological disorders in 'Atlantic' potato through various treatments of mulching, periodic shadings, and plant growth regulators such as trinexapac-ethyl (Tr-E) and dicloprop-triethanol mine (DTA). IBS occurrence was as high as 67.5% in the field plot mulched with transparent film and shaded for 10 days beginning at 80 days after planting. The highest level of HH was 22.9% in the plot mulched with transparent film and shaded for 10 days beginning at 60 days after planting. Very high level of IBS (66.3%) also occurred in the plot treated with 1500 mg/L of Tr-E 40 days after planting, while HH occurred by 21.3% in the plot treated with 1000 mg/L of DTA 70 days after planting. In the plots which were treated with 1,500 mg/L of Tr-E after 40 days of planting and 1000 mg/L of DTA after 70 days of planting, 'Superior' (moderately highly resistant) and 'Atlantic' (very susceptible) could be clearly distinguished to be resistant and susceptible. High occurrence condition set up in this study could be applied for the potato breeding program to screen potato clones with high resistance to HH and IBS.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.36 no.1
• /
• pp.57-64
• /
• 1991

This experiment was conducted to elucidate the effect of plant growth regulators (PGR) on the root -mat formation of infant seedling (8- to 10-day-old seedling) of rice in machine transplanting. The rice seeds of Odaebyeo were socked in water with different concentrations of PGRs for 48 hours at room temperature. Seeding rate was 220 g per seed tray (30x60x3cm). Metalaxyl (25% wettable powder) was used for a fungicide. Generally, the metalaxyl-treated seeds markedly promoted the root growth of the rice seedling, while tetracy-cle, pachlobutrazol and NTN -821 reduced the seedling height and root length, and thickened the shoot diameter at higher concentation levels. Tetracycle decreased root length of the rice seedlings but increased root number per seedling, and root-mat formation was poor. Whereas, metalaxyl concentrations of 200 and 1,000 ppm markedly increased root length and number of root hairs without decreasing root number, thus root-mat formation was excellent. The optimum concentration of metalaxyl seed treatment to increase the root-mat formation of infant seedling of rice was about 200 ppm. Metalaxyl seed treatment could be advanced one to two days of the duration of root-mat formation compared with control.

• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 1999.04a
• /
• pp.75-78
• /
• 1999

토마토의 육묘시에 화아분화에 미치는 제요인의 영향에 대한 정확한 정보는 미흡하다. 흔히 육묘 중인 토마토의 생식생장을 촉진하기 위해서는 질소비료의 공급량을 줄이고 야간기온을 낮추어 야냉육묘해야 한다고 알려져 있다. 그러나 공정육묘기술의 도입으로 인하여 다품목 소량생산을 위주로 하는 국내의 채소 육묘농가들이 다양한 종류의 묘를 하나의 온실에서 생산해야 하는 한계성을 가지고 있다. (중략)

• Journal of Sericultural and Entomological Science
• /
• v.4
• /
• pp.27-31
• /
• 1965

The aim of this work was to investigate how the mulberry shoots grew well when the mulberry branches were cut down, in hight, 1/3, $\frac{1}{2}$ and 2/3 of them, respectively, just before the Spring budding. The results obtained are as follows: 1. The rate of un-sprouted buds decreased sharply down as much as half of the control if the mulberry branches were cut off. The treatment, 1/3, was best one of various cut down sizes and the un-sprouted buds concentrated on the lower parts of the branches. 2. Even though the branches were cut down, at first it seemed flat to accelerate the sprouting of buds, but rather to have a tendency to become late. The speed of leaf growth, however, became faster after the sprouting. It took 7~9 days from the beginning of buddings to the 5th full grown leaf, and.7 days for the shortest one in the treatment, 2/3, when compared with 16 days of the control. 3. If the branches were cut down, the growth of the new sprouts was accelerated. For 45 days (on 5th of May to on 10th of June), therefore. the shoots had grown up to 1.6～2.5 times of the control, 34cm long. The shoots of which the branches were cut down at 2/3 of them were longest (83cm). Furthermore. the speed of shoot growth of cut-down branches was faster than that of the control. 4. In the increased rate of the number of the mulberry leaves, there was not significant difference between the control and the treatments. 5. The total amount of shoot growth showed considerably much more in the treatments than in the control. The successing growing shoots of treatment, 2/3 were little in a number but longest per one shoot in mean shoot length. 6. It seems to be much available that we may cut down branches at 2/3 of them in order to get the scions for the cutting as soon as possible.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.27 no.2
• /
• pp.111-115
• /
• 1982

The trials were carried out for improvement of early maturing wheat varieties, desease resistant and good quality through transfering good characters of barley to the wheat, during 1980-'81. For these purpose, Chinese Spring, a wheat variety was used as male and Manker 16 a barley variety, as female parents. EACA($\varepsilon$-Amino Caprolic Acid) known as an inhibitor of blood coagulation was injected to all barley from 14 days until heading with 1$m\ell$ per culm at the level of 500ppM. $GA_3$ solution which accelerates pollen activity was also used with 75ppM concentration after pollination for two days including check to determine the single effect of EACA. Two different methods of the cross were used. One was bud-pollination, another was post-pollination. The result indicated that the post-pollination was better than bud-pollination in terms of pollination rate, even though formation rate of normal embryo was seemingly adversed. The new plant derived from barley-wheat cross was similar in phenotype to the wheat.

• Research in Plant Disease
• /
• v.26 no.1
• /
• pp.8-18
• /
• 2020

Red pepper, one of the major economic crops in Korea, is being affected by anthracnose disease caused by Colletotrichum acutatum. To control this disease, an antagonistic bacterial strain, Bacillus subtilis YGB36 identified by 16S rDNA sequencing, physiological and biochemical analyses is used as a biological control agent. In vitro screening revealed that the strain YGB36 possess strong antifungal activity against the pathogen Cylindrocarpon destructans. The strain exhibited cellulase, protease, amylase, siderophore production and phosphate solubility. In vitro conidial germination of C. acutatum was most drastically inhibited by YGB36 cell suspensions (10⁶ cfu/ml) or culture filtrate. Development of anthracnose symptoms was reduced on detached immature green pepper fruits by treatment with cell suspensions, and its control value was recorded as 65.7%. The YGB36 bacterial suspension treatment enhanced the germination rate of red pepper seeds and promoted root development and growth under greenhouse conditions. The in vitro screening of fungicide and insecticide sensitivity test against YGB36 revealed that the bacterial growth was not affected by any of the insecticides, and 11 fungicides out of 21 used. Collectively, our results clearly suggest that the strain YGB36 is considered as one of the potential biocontrol agents against anthracnose disease in red pepper.

• Journal of Life Science
• /
• v.21 no.7
• /
• pp.969-975
• /
• 2011

We focused on relationship between phytohormones and AtEXPA3 gene in gravitropic response of A. thaliana. RT-PCR analysis shows that AtEXPA3 was highly expressed in actively developing tissues such as leaf, rosette, root and flower tissues. AtEXPA3 gene expression was enhanced by gravistimulation, BR and IAA. Furthermore, decreased gravitropism was observed when treatment of AVG, an ethylene biosynthetic inhibitor, suggesting that ethylene has a gravistimulating effect itself as well as BRs and IAA. Inhibition of gravitropism in AtEXPA3 RNAi mutant suggests that BR, auxin and ethylene are playing roles as regulators of AtEXPA3. In addition, altered gravitropism in BRs signaling mutant (decreased in bri1-301, bak1, and increased BRI-GFP) indicated that BRs signaling mediated the gravitropism. In conclusion, gravitropic responses of Arabidopsis root resulting from root growth were mediated by increased expression of AtEXPA3 gene, which is stimulated by phytohormones.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.39 no.2
• /
• pp.128-138
• /
• 1994

To improve seed vigour in rice, barley and soybean, several methods of presowing treatment, using chemicals and priming in polyethylene glycol solution, were investigated. Gibberellic acid($GA_3$) slightly improved germination of rice, but other chemical treatments showed no beneficial effect on seed vigour. Aged seeds were primed in polyethylene glycol solution then rinsed and germinated with drying back. In general mean germination time increased and percentage germination decreased with in- creasing water potential of the priming solution, but there were no significant effects on spread of germination times. Priming also showed no marked improvement in germination under cold, wet, or osmotic conditions. None of the treatments used was successful in practically improving the seed germination and vigour of the tested crops. However, seed treated with GA$_3$ gave the best overall germination response.

• Korean Journal of Plant Tissue Culture
• /
• v.22 no.2
• /
• pp.89-93
• /
• 1995

Regeneration and growth of bulblets from bulblet-derived bulb-scale segment of Lilium longiflorum (cv Georgia) were investigated. Bulblets were initiated on bulb scales taken from bulblets on MS medium containing 0.05 mg/L 2,4D with 3% sucrose or 0.02 mg/L 2,4D with 9% sucrose. Benzyladenine promoted the differentiation of bulblets but inhibited the growth of differentiating bulblets. The growth of bulblet was promoted by supplying 1/2 strength 1/2 NH$_4$NO$_3$ concentration in MS medium containing 12% sucrose.

• Journal of Environmental Science International
• /
• v.3 no.2
• /
• pp.141-155
• /
• 1994

The effect of growth regulators (NAA, BA and $ extrm{GA}_3$) and light (blue, red and far-red) on the changes in total protein and thylakoid membrane protein pattern of callus from intergeneric protoplast fusion between Nicotiana tabacum and Solanum nigrw were investigated. When the callus were irradiated with different wavelengths of light, blue and red light accelerated the synthesis of total proteins and thylakoid membrane proteins. Particularly, red light led to an increase in the protein synthesis compared to blue light. When the callus were subjected to various combinations of growth regulators, NAA+$ extrm{GA}_3$ and NAA+BA treatments induced remarkable increase of total proteins and thylakoid membrane proteins accumulation, particularly in the combination of NAA+$ extrm{GA}_3$. NAA.$ extrm{GA}_3$ treatment with irradiation of red ligh showed highest value in the accumulation of total proteins and thylakoid membrane proteins. We conclude that simultaneous application of red light and NAA+$ extrm{GA}_3$ treatment may induce synergistic effect in the synthesis of total proteins and thylakoid membrane Proteins.