• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.421-427
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• 2020

In this study, we investigated the effect of nutrient supply periods on the fruit growth and quality of 'Duke' blueberry. The nutrient solution was contained with NO₃-N 4.6, NH₄-N 3.4, PO₄-P 3.3, K 3.0, Ca 4.6, and Mg 2.2 mmol·L^-1, and EC in the nutrient solution was 1.5 ds.m^-1. In 2017 and 2018, an individual blueberry bush was supplied with 8 L of the nutrient solution per week. In 2018, the drainage water quality of growing medium and fruit quality was investigated. The nutrient supply was started from April 01, and stopped at 15 days intervals as follows, 15 days before final harvest, at the final harvest date (June 30), 15 days after final harvest (DAFH), 30 DAFH, 45 DAFH, and 60 DAFH. The content of inorganic components in the growing medium was not significantly different by the stop time of nutrient supply, but the content of phosphorus (P₂O₅) tended to increase with the delay of stop time of nutrient supply. There were no significant differences in the fruit quality characteristics in terms of size, sugar content, and acidity among the different stop time of nutrient supply. The blueberry yield was tended to decrease with the delay of periods of nutrient supply, while the lowest yield of 1.8 kg was recorded when nutrient supply stopped at 45 and 60 DAFH.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.333-340
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• 2011

This study was conducted on the effect of plant growth retardants (PGRs) on growth of potted Ardisia pusilla and Ardisia pusilla var. variegata grown for a short term in an ebb and flow system. Plants were planted in 10 cm plastic pots, containing a mixture of peat moss and perlite (1 : 1, v/v) on 30 June 2005 and were grown until 23 Sep. 2005. The PGRs used were 50, 200, 350, 500 $mg{\cdot}L^{-1}$ daminozide (B- 9), 10, 40, 70, 100 $mg{\cdot}L^{-1}$ paclobutrazol (Boundy), and 5, 15, 25, 35 $mg{\cdot}L^{-1}$ ethephon (Florel). On every irrigation, the nutrient solution containing PGRs was supplied at a 2 cm depth and was kept for 15~20 minutes. The surplus nutrient solution was drained back into the tank for next irrigations. In both cultivars, paclobutrazol gave the most pronounced effect in inhibition of stretchiness. Ardisia pusilla, which was pinched just before initiation of paclobutrazol treatment, resulted in the greatest inhibition of shoot elongation. Daminozide treatments above 200 $mg{\cdot}L^{-1}$ also gave reduction of shoot length. However, ethephon treatments gave no dwarfing effect in Ardisia pusilla. Inhibition of stretchiness was observed even in the lowest concentration treatments. Among the PGRs, paclobutrazol was the most effective in suppressing plant stretchiness.

• Journal of Sericultural and Entomological Science
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• v.4
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• pp.27-31
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• 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 Weed Science
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• v.16 no.4
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• pp.301-308
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• 1996

In this study, a propagation characteristics of green kyllinga(Kyllinga brevifolia var. leiolepsis H.) was investigated. Two to three rhizomes(1st rhizome) arised from the basal part of main shoot at 4th leaf stage and were grown to extend on the soil surface. Then new shoots(lst tillers) emerged from every node of the 1st rhizome. Second rhizomes also arised from the basal part of lst tiller at the time of 4th leaf openning. With such a regularity, 5th rhizomes and about 688 shoots were produced from one plant during one year-cultivation without competition under the natural condition. The degree of vegetative growth and seed formation was 3 times and 2.5 times higher in rhizomeoriginated plant than in that from seed, respectively. The amount of seed formation and the 1000 seeds weight was highest in one planted on June 1 and Aug. 1, respectively. Short-day treatment of less than 14hr appeared to be necessary for the induction of flowering and it was effective as treated not during germination but since at least 2 leaf stage of green kyllinga. Each shoot individually responded to short-day. When plants were exposed to short-day (9hr, day / 15hr, night) treatment at the stage of 2-3 leaves, more than 7 cycles were required for flowering induction. Bolting in main shoot occurred after emergence of 4 leaves under the short-day condition. Exogenous $GA_3$ slightly accelerated the velocity of bolting only in short-day condition.

• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.190-195
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• 2006

The purpose of this study was to figure out the best condition in growth and sod quality of Mentha spp. according to cutting methods and soil depth. Applemint (M. suaveolens), Peppermint (M. piperita), and Spearmint (M. spicata) were used. Regardless of cultivar and soil depth condition, the growth rate in top cutting was higher than layering method. The difference between layering and layering without apical meristem was not significant. Optimal condition for growth was 5cm depth of soil. However, the shallower the depth of the soil, the better quality of sod. Among three Mentha species, M suavelens showed plant height and node number and M. piperita had shoot number were higher than other variety. The best condition of sod was top cutting and 1cm depth of soil regardless of cultivar.

• Journal of Korean Society of Forest Science
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• v.75 no.1
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• pp.19-24
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• 1986

Present studies were carried out to understand the way of propagation of Osmanthus which has much value as ornamental trees in southern parts of Korea. The results of these experiments were summarized as follows: 1. In order to increase the survival of Osmanthus, scions of Osmanthus was grafted on the stocks of Ligustrum obtusifolium S. et Z. The survival of the grafts were 63% for Osmanthus fragrans var. aurantiacus Makino and 60% for Osmanthus asiaticus Nakai. 2. The growth of the grafts was initiated from 28th day after the grafting and the height growth resumed three times, and the growth percentage was 63% for Osmanthus fragrans var. aurantiacus and 59% for Osmanthus asiaticus. 3. Cutting medium mixed with perlite and vermiculite (1:1) gave better results than either use of them separately, and the rooting percentage was 93% for Osmanthus fragrans var. aurantiacus and 90% for Osmanthus asiaticus. 4. Rooting percentage of cuttings was lower in hard-wood cutting than that of in green-wood cutting. 5. Grafts showed fairly good height growth in July and September, and ceased growth in October. 6. Correlation between height growth and diameter of root collar of grafts in case of Osmanthus fiagrans var. aurantiacus was highly significant and showed linear correlation ($r=0.70^{**}$)

• Research in Plant Disease
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• v.14 no.3
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• pp.159-164
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• 2008

Crown gall of rose (Rosa hybrida) was observed in greenhouse during 2003-2007. The average disease incidence was up to 38.1 % and was more severe in hydroponic culture as compared to soil culture. The typical gall symptom occurred mainly on the root, crown, or both, and resulted on poor rooting, growth retardation and yield loss. The reduction rate of rooting influenced by crown gall was 57.5% as compared to healthy plants on nursery stock. The location of gall formation in the plant influenced growth vigor resulting in symptoms such as poor shooting. Healthy plants produced 19.1 flowers/$m^2$, while diseased plants produced 9.5 flowers/$m^2$ during the same cultivation period. Moreover, the number of days to flowering was longer for the diseased plants than for healthy plants - 51.2 days and 39.8 days for first harvest, and 60.6 days and 52.1 days for the second harvest, respectively. Conclusively, infection on the basal stem caused serious loss of the number of shoot formation; yield loss of cut flower was 38.7% due to crown gall infection and delay of harvesting time about 8-10 days.

• Horticultural Science & Technology
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• v.19 no.3
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• pp.367-372
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• 2001

'Kyoho' grape (Vitis labruscana L.) has currently cropped twice a year in plastic greenhouses. However, there are problems with low fruit quality in the second cropping owing to low temperatures and short photoperiods. This experiment was conducted to investigate the effect of root zone heating and $CO_2$ enrichment in plastic greenhouse on the vine growth and fruit quality of 'Kyoho' grape in double cropping system. The internode length of shoots, leaf area and leaf dry weight at the treatment of soil heating near root zone was significantly different regardless of $CO_2$ enrichment. There were no significant differences in fruit bunch and berry weight, titratable acidity, coloration degree and berry shattering among the treatments, but the soluble solids significantly increased by root zone heating. Photosynthetic rate increased with increasing $CO_2$ concentration from 300 to $800{\mu}mol{\cdot}mol^{-1}$ in sunny day, whereas it didn't increase in cloudy day regardless of $CO_2$ enrichment.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.23-29
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• 2013

This study was conducted to clarify effects of weed control methods on damages from agricultural chemicals of pear trees, growth of weeds and states of pear trees after treating pear orchards with different methods of weed controlling, density of GLU and application times. The growth and occupation rate were investigated after 10, 20 and 40 days of weeding treatment. According to a result of the first treatment conducted when weeds in the lower parts of crown in a pear orchard began to grow and grew about 20 cm, unwoven cloth covering showed the highest control value with 100% in all 14 kinds of grasses. In comparison, Stellaria aquatica and catchweed bedstraw showed 96.7% and 97.3% respectively in the 20 DAT investigate after the first treatment of GLU 540 g a.i. ha-1 and the high control value of 100% in other all kinds of grasses. According to an investigation of stalk enlargement, length of new shoot and the number of new shoot made to know differences in tree growth following treatment of the lower part of crown, to use weed killers two or three times a year or to eliminate grasses with machines have positive effects on cross growth of pear trees.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.1-10
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• 2015

This study was conducted in three years (7-9 years after planting) to investigate vegetative growth, yield, fruit quality, and return bloom for optimum crop load based on different planting densities of adult 'Fuji'/M.9 apple trees. As plant materials, 'Fuji'/M.9 apple trees planted at $3.5{\times}1.5m$ (190 trees per 10 a), $3.5{\times}1.2m$ (238 trees per 10 a), and $3.2{\times}1.2m$ (260 trees per 10 a) spacing and trained as slender spindles were used. The crop load was assigned to five different object ranges as follows: 55-64, 65-74, 75-84, 85-94, and 95-104 fruit per tree. TCA increment, total shoot growth, return bloom, yield per tree, and yield efficiency tended to increase as planting density decreased, and fruit weight and soluble solid content tended to increase as the object range of crop load decreased. Fruit red color tended to increase as shoot growth decreased. For apple trees planted with 238 trees and 260 trees per 10a, biennial bearing occurred when the crop load was over 85-94 and 75-84 fruits, respectively. However, biennial bearing did not occur when the crop load was 95-104 fruits in apple trees planted with 190 trees per 10a. Accumulated yield tended to increase as planting density and crop load increased, but that of biennial bearing did not show such a difference. Based on our results, optimum crop load recommendations are to set 95-104 fruits per tree in 'Fuji'/M.9 mature apple trees planted at 190 trees per 10a, 75-84 fruits per tree at 238 trees per 10a, and 65-74 fruits per tree at 260 trees per 10a.