• Korean Journal of Environmental Agriculture
• /
• v.41 no.4
• /
• pp.328-334
• /
• 2022

BACKGROUND: The low temperature at flowering period break the balance between vegetative and reproductive growth of apple tree. Summer pruning has been used to control vegetative growth. So, this study was conducted to investigate the effect of summer pruning time on shoot growth and fruit quality of 'Fuji'/M.9 apple trees damaged by the low temperature at flowering period. METHODS AND RESULTS: The following treatments were applied to tree : a) control (no summer pruning), b) pruned 26 June, c) pruned 30 July, d) pruned 28 August, and e) pruned 26 September. The summer pruning significantly increased light penetration and fruit red color by reducing the total shoot growth compared with control. And the summer pruning control the outbreak of apple valsa canker. But the summer pruning at the end of June increased regrowth of shoot and pruning weight compared with the summer pruning at the end of August. The summer pruning at 30 July had the highest fruit weight, but return bloom was the highest in the summer pruning at 28 August. CONCLUSION(S): These results indicated the optimum summer pruning time of 'Fuji'/M.9 apple trees damaged by the low temperature at flowering period were the end of August.

• Journal of Bio-Environment Control
• /
• v.25 no.4
• /
• pp.328-333
• /
• 2016

This study was conducted to determine the influences of winter and summer pruning on the yield and fruit quality in southern highbush blueberry (Vaccinium corymbosum L. hybrid) cv. 'Misty'. The 5-year-old southern highbush blueberry 'Misty' were used. The pruning treatments were as follows: 1) control (no pruning), 2) winter pruning (30% removed), and 3) winter pruning + summer pruning (Aug. 5). Fruits harvested for six times over the harvest season and measured yields, unmarketable fruit (defected and immature fruit), changes of each fruit weight and analyzed fruit characteristics, such as total sugar, total anthocyanin contents and total phenolic contents. The differential pruning treatments were not significant for fruit yields of southern highbush 'Misty'. No pruning treatment showed regular yields after the 2nd harvest, but the other pruning treatments were appeared that fruit yields were more concentrated on the 2nd~4th harvest time. Total sugar and total phenolic contents were observed the highest at the 4th time among the harvest period. No pruning treatment showed the highest unmarketable fruit yield at 57%, however, that of winter pruning and winter + summer pruning treatment occurred at 26%, 31%, respectively.

• Journal of Bio-Environment Control
• /
• v.30 no.3
• /
• pp.183-187
• /
• 2021

Appropriate pruning is very important for southern highbush blueberries cultivated in a heated plastic house to control their severe crowding within the bush canopy after harvest. Pruning treatments at different times were evaluated to find out an appropriate pruning time to southern highbush 'Scintilla' cultivation with heating. Seven-year-old (2018) bushes, grown in 180-L containers, were summer-pruned on May 20 (35-39 days after harvest) and June 20, or dormant-pruned on December 20 (5 days before flowering), consecutively in both 2018 and 2019 removing 30% of the total woods. May pruning activated occurrence of shoots the following years, increasing number of shoot by 17 to 49% and total shoot length by 18 to 32% compared with those of the dormant pruning. Fruit characteristic was not significantly affected by different pruning times the previous year. The first year pruning treatment did not influence the yield the following year, but the second year consecutive May pruning significantly increased yield per bush by 7% compared with the dormant pruning. The results indicated that summer pruning in May could be favorable to promote shoot growth and to maintain stable yield.

• Horticultural Science & Technology
• /
• v.17 no.3
• /
• pp.333-336
• /
• 1999

Current season's shoots on 2-year-old branches of 'Fuji' and 'Jonagold' apple trees were heading back pruned to 5 leaves from early May to mid July at about 12-day intervals. The summer heading back pruning induced regrowth on the pruned shoots with different responses between the two cultivars. Generally, greater regrowth occurred on the pruned shoots of 'Fuji' trees than on those of 'Jonagold', irrespective of the time of the heading cut. The shoots of 'Fuji' trees pruned in late May or in June exhibited greater regrowth compared with those pruned in early May or in July, whereas the summer heading back pruning in June resulted in the greatest regrowth for 'Jonagold'. The heading cut induced terminal flower bud formation on the pruned shoots, the percentage of which was higher in 'Fuji' than in 'Jonagold'. The highest percentages of terminal flower bud formation for 'Fuji' and 'Jonagold' were obtained with the heading cut in late May and in mid June, respectively. Percent flowering of the buds was similar in both cultivars, but percent fruit set was slightly higher in 'Fuji' than in 'Jonagold'. The time of the heading cut did not affect percent fruit set in both cultivars. Our results demonstrate that summer heading back pruning of current season's shoots induces regrowth and terminal flower bud formation therefrom when done at appropriate time, but the specific responses to the heading cut are cultivardependent.

• Horticultural Science & Technology
• /
• v.18 no.3
• /
• pp.378-382
• /
• 2000

For the production of second crop in 'Campbell Early' grape, the primary shoots were pruned at 3rd, 6th or 9th nodes from the shoot bases on 13 days, 23 days and 33 days after full bloom date on 7th June. Secondary shoots were sprouted 7~8 days after the pruning, and it took 19~25 days for the flowering on the secondary shoots. The flower cluster number on secondary shoots were 2.8 for 13 days after full bloom, and 3.2 for 23 days and 33 days after full bloom, meaning little effect by pruning time. The 3rd node pruning produced 2~2.4 flower clusters with flower cluster length of 9.3~10.4 cm, while the 6th or 9th node pruning produced 3.1~3.8 flower clusters with flower cluster length of 12~14.9 cm, showing superior flower cluster length for the 6th or 9th node pruning. The secondary shoots developed from the buds pruned 13 days after full bloom with pruning bud positions of 6th nodes demonstrated superior fruits with higher soluble solids and lower acidity than the rest of the pruning times and positions.

• Journal of Bio-Environment Control
• /
• v.23 no.3
• /
• pp.167-173
• /
• 2014

This research was conducted to establish appropriate methods to prune tomato side stems during summer. Cherry tomatoes "Unicorn" (Monsanto Korea, Korea) were grown in the coir based growing medium, and irrigation was controlled time based system. There were three pruning treatments: 1) removing all side stems (ACUT), 2) remaining two leaves on the side stems right below any cluster (PCUT), and 3) remaining two leaves on all side stems (LEFT). Experimental results showed that the occurrence of swollen stems, a symptom of nutrient excess, was influenced by side stem pruning due to blocking of consumption of photosynthetic products. The photosynthetic rate was not different between leaves on main stem and those on side shoots. Therefore the differences in the total amounts of photosynthetic products seemed to come out from the differences in leaf areas on each treatments, influencing on fruit yield difference. The yields and harvesting rates were better in ACUT treatment when tomato plants were harvested until $5^{th}$ cluster, however tomato yield was higher in LEFT treatment when more then $5^{th}$ clusters were harvested.

• Horticultural Science & Technology
• /
• v.33 no.4
• /
• pp.479-485
• /
• 2015

This study was conducted to study the factors inducing micro-cracking and determine proper practices to reduce its occurrence in 'Mansoo' pear fruits. Micro-cracking was observed on ripe fruits. Occurrence of micro-cracking was closely related to sun duration time in August. Micro-cracking occurred severely with shorter sun duration, but weakly with longer sun duration and continuous sunlight. Micro-cracking fruits occurred more frequently in trees with a pergola training system than in those with Y-trellis, but there was no difference between the irrigated and non-irrigated groups. While no micro-cracking was observed without fruit bagging, micro-cracking occurred in fruits with black and yellow outer paper bagging at rates of 62.2 and 17.3%, respectively. Our results suggest that the light condition was the most important cause of micro-cracking because the occurrence of micro-cracking in 'Mansoo' fruits was affected by factors including sun duration, trellis system and fruit bag color. We suggested that micro-cracking could be reduced in 'Mansoo' fruit by optimizing the light conditions with the proper trellis system, bagging color and summer pruning.