• Horticultural Science & Technology
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• v.34 no.2
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• pp.257-268
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• 2016

Physiological characteristics of five new apple cultivars from the Korean apple breeding program were evaluated as a function of harvest time and storage after harvest. Internal ethylene concentration (IEC), flesh firmness, soluble solids concentration (SSC), and titratable acidity (TA) were measured in 'Summer Dream', 'Summer King', 'Green Ball', 'Picnic', and 'Hwangok' apples at harvest, during shelf life at $20^{\circ}C$, and one day after cold storage at $0.5^{\circ}C$ in air. IEC increased during shelf life in 'Summer Dream', 'Summer King', and 'Green Ball' but not in 'Picnic' or 'Hwangok', regardless of harvest time. Flesh firmness decreased towards harvest time and decreased gradually with time in cold storage only in the former three cultivars. In turn, IEC increased during cold storage in the first three cultivars but not for the last two cultivars, irrespective of harvest time. Changes in SSC and TA did not consistently relate to harvest time or storage period but TA tended to decrease as IEC increased. Furthermore, IEC was negatively correlated with flesh firmness except in the 'Green Ball' cultivar but the significance level was much greater in 'Summer Dream' and 'Summer King' (p < 0.0001) than in 'Picnic' (p < 0.01) or 'Hwangok' (p < 0.05) cultivars. Flesh firmness was positively correlated with TA in the first three cultivars but not in the last two cultivars. Overall, the results indicate that cultivars for which IEC increased after harvest had reduced flesh firmness and TA after storage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.2
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• pp.126-133
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• 1988

To know the optimum harvest time for seed yield and seed quality a local variety of rye 'Paldang-homil'was harvested at seven different harvest times from 25 to 55 day after heading (DAH) at five-day intervals in 1984 ani 1986. Seed development, seed germination and seedling growth were observed. The l000-grain weight increased as harvest time delayed until 50 DAH in both years. Although grain yield tended to increase with delay of harvest time, the yield differences between succeding harvest time was highest between 40 DAH and 45 DAH. Germination rate of seeds harvested before 30 DAH were lower than those after 35 DAH at 20 C, but at 10 and 30 C before 35 DAH were lower after 40 DAH. Plant height and dry weight of seedlings increased with delay of harvest time up to 45 DAH in pot. Heading stages were similar among the seeds harvested 40-55 DAH. Culm length was not different among the harvest times. The optimum harvest time for seed production of rye seems to be 45 DAH (38 days after flowering).

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.1
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• pp.15-20
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• 1990

This experiment was carried out to investigate the effects of the fist harvesting times (vegetative, stem elongation and heading stage) and regrowth periods (20, 30 and 40 days) after the first harvest on dry matter (DM) productivity, crude protein (CP), CP yield and cell wall constituents of gasses during 1987 and 1988. Although the dry matter productivity of grasses at the first was decreased with earlier cutting, the regrowth DM productivity after the first harvest was increased significantly with earlier cutting (p < 0.05). Also the 30 days of regrowth periods was contributed greatly to the DM productivity p <0.05). The percentage of leaf in the leaf: stem ratio was increased with earlier initial harvest and shorter regrowth period after first harvest. The nutritive value of grasses was increased with earlier initial harvest and the 30 days of regrowth period after fist harvest. Based on the results, it is suggested that good grass DM productivity and nutritive value could be achieved by the earlier harvest at first and the regrowth period of 30 days after first harvest in spring.

• Journal of Sericultural and Entomological Science
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• v.40 no.1
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• pp.8-12
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• 1998

The study aimed at development of a riding-type mulberry harvester for mechanical harvest. A riding-type mulberry harvester has been developed to harvest on sloped land with a higher efficiency. It has been implemented over a period of 2 years from 1996 to 1997. The result is as follows. It moves on carterpillar with a level adjusting system. It reduced only from 14.6 hrs to 0.9hrs/10a for cutting in a range of 25 to 80 cm high and possibly used for both spring and autumn. It reduced only the labor requirements of mulberry harvesting by 94 percent, as compared to that of the manual harvest. All related processes, cutting, binding and loading are simultaneously done by this harvester and totally it can reduce 96 percent of the labor requirements, as compared to 20.4 hrs/10a of the manual harvest. The machine compared to improved mulberry harvest efficiency with 11.11a per hour by about 23 times as compared to 0.49a per hour manpower. Cost analysis indicated that the riding-type mulberry harvester saved overall cost by 66 percent from 980,000 won per ha manpower to 330,000 won per ha.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.159-164
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• 2007

Pea weevil was easily observed in the flower and pod of garden pea, but not observed in soybean at various locations in Yeongnam district through 2001 to 2003. Number of pea weevil observed in pea flower was the highest at Milyang (20), followed by Yangsan (15), Sacheon (14) and Changnyong (13), and was the lowest at Pohang (3). On the other hand, number of pea weevil observed in pea pod was the highest at Tongyeong (192), followed by Changnyong (171), Sacheon (157) and Changwon (138), and was the lowest at Pohang (12) which showed simila. tendency with the result of pea flower. Number of pea weevil occurrence observed in pea pod after one and two times applications of Insecticides in pea field were different at harvest day of 30th May while were not significantly different at harvest day of 5th June. Likewise, number of pea pod damage after one and two times applications of insecticides were different at harvest day of 10th May while was not different at harvest day of 5th June. Thus, control efficacies of insecticides according to application times against pea weevil showed very high with above 95% at harvest day of 6th June while showed variable control efficacies at harvest of 30th May.

• Korean Journal of Medicinal Crop Science
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• v.8 no.1
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• pp.58-63
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• 2000

Changes of yield and paeoniflorin content according to chemical control and harvest time were investigated. Peonies were harvested after four years from planting. Disease and pest control method was applied normally in first year. From second year to forth year we set two blocks and controlled them differently. In one, peonies were withered early under non-control condition. In the other which was controlled by spraying chemicals four time a year, top part withering was delayed. Harvest was taken four times top part withering was delayed. Harvest was taken four times: Jul. 25, Aug. 25, Sep. 25, and Oct. 25. In non-chemical, at harvest of Jul. 25, paeoniflorin content was highest and dry root weight was 1,126kg/10a which was little less than 1,177kg/10a of Aug. 25. In chemical control, dry root yield of Oct. 25. showed an increase of 33% over that of Jul. But paeoniflorin content in root at Oct. was lower than at Jul. or Aug. For high qualities and harvest yields of peony root, chemical control is necessary to maintain top part to late in Oct.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.5
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• pp.361-367
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• 2002

In order to determine the optimum harvest time for the seed production of inbreds and hybrids in silage corn, the ears of sib-pollinated 'KS5', 'KS7rhm', and 'Ga209' and cross-pollinated 'KS5' $\times$ 'KS6' (Suwon19), 'KS7 rhm' $\times$ 'KSl17' (Suwonok), and 'Ga209' $\times$ 'DB544'(Kwanganok) were harvested at the one-week intervals from 4 to 10 weeks after silking. The optimum harvest time for the seed production for 'KS5', 'KS5' $\times$ 'KS6', 'KS7 rhm', and 'KS7rhm' $\times$ 'KS117' was 7 weeks after silking considering both emergence rate and plumule growth in cold test. Although earlier harvested seeds showed similar germination rate as the seeds harvested at the optimum time at $25^{\circ}C$, their emergence rate were lower in cold test. Seed weight and $\alpha$-amylase activity of earlier harvested seeds were lower compared to those of seeds harvested at the optimum time, while leakage of total sugars and electrolytes were higher. However, the later harvested seeds showed lower germination rates at $25^{\circ}C$ and emergence rates in cold test probably due to the lower $\alpha$-amylase activity although they showed increased seed weight and reduced leakage of total sugars and electrolytes. In contrast, the emergence rate of 'Ga209' and 'Ga209' $\times$ 'DB544' in cold test increased up to 10 weeks after silking probably due to the increased seed weight and $\alpha$-amylase activity and reduced sugar and electrolyte leakages during the germination. The cross-pollinated F$_1$ hybrid seeds showed higher germination and emergence rates at $25^{\circ}C$ and in cold test, and higher plumule growth and $\alpha$-amylase activity compared to those of sib-pollinated inbreds.

• Korean Journal of Agricultural Science
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• v.46 no.1
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• pp.125-135
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• 2019

Late-maturing Dark Horse, and early-maturing High Speed oat varieties were seeded on March 3, 2016 and harvested on three periods: May 31, June 10, and June 20 coded as early, mid, and late-harvest, respectively. Dried and ground samples were subjected to chemical analysis to determine nutritional values such as crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), organic matter (OM), and total digestible nutrient (TDN). Effective degradability (ED) of nutrients and fermentation characteristics including volatile fatty acid (VFA) composition, pH, gas production, and ammonia-N concentration were evaluated through an in vitro digestion method. Varieties of oat hays showed significant difference in terms of nutritional value, ED, and fermentation characteristics. Dark Horse showed higher CP and OM, and lower EE contents than High Speed. Dark Horse also showed higher EDDM (dry matter), NDF, ADF, and OM than High Speed, and although High Speed showed higher pH and ammonia-N, it had lower gas and total VFA production than Dark Horse. However, in terms of harvest period, significant difference was only observed in Dark Horse where early-harvest increased the CP, and late-harvest increased the NDF and OM contents. In addition, early-harvest of Dark Horse increased the EDDM and EDNDF of the forage. Therefore, early-harvest of late-maturing Dark Horse would give better nutrient efficiency than High Speed. Allowing Dark Horse to advance in maturity would decrease its nutrient productivity and efficiency.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.3
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• pp.215-222
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• 2016

Nitrogen (N) fertilizer management is one of the important aspects of economic production of sorghums in sustainable agriculture. The aim of the study was to evaluate the effects of different N application rates and its split N application methods on productivity, growth characteristics, N accumulation, N use efficiency (NUE), and feed value of Sorghum ${\times}$ Sudangrass hybrids. Treatments consisted of five N application rates (0, 150, 200, 250, and $300kg\;ha^{-1}$) and two split N application methods (40% in basal N, 30% at the growing stage, and 30% after the first harvest vs. 50% in basal N and 50% after the first harvest). Plant height, leaf width, and stem diameter were increased ($p{\leq}0.05$) with increasing N fertility rates at each harvest. Chlorophyll content (expressed as SPAD values) was the highest at a rate of $300\;kg\;N\;ha^{-1)$ (first harvest, 46.32; second harvest, 33.09). It was the lowest at zero N (first harvest, 21.56; second harvest, 18.5). Total N, N uptake, and NUE were increased with higher N rates. Split N application had little effect on total N, amount of N uptake, or NUE. Total dry matter yields were the highest ($21,715\;kg\;ha^{-1}$) at a rate of $300\;kg\;N\;ha^{-1}$. It was the lowest ($10,054\;kg\;ha^{-1}$) at zero N. Our results suggest that more than $300\;kg\;N\;ha^{-1}$ can improve dry matter yield to be above 116% compared to zero N, thus enhancing the agronomic characters of sorghums. However, no significant effect had been found for split N application. Further work is needed to determine the optimal N levels and the effect of split N application rates.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.3
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• pp.43-50
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• 1979

The effect of planting time and density of soybean on the yield component and yield when intercropped within barley rows or seeded after harvest was evaluated. Early maturing barley variety 'Olbori' was seeded at 2 levels of planting density 40 ${\times}$ 18 and 60 ${\times}$ 18 (row-hill space in em), and the soybean, variety "Dongbuktae", was seeded on June 1 as a inter-crop, June 15 and 30 as a afterharvest crop, all 2 levels of row space (40, 60 cm) and 3 levels of hill space (10, 15, 20 em). Soybean yield was increased in the following conditions: early seeding of soybeans within rows at 60 ${\times}$ 20 em density and soybean seeding after barley harvest at 40 ${\times}$ 20 em density./TEX> 20 em density.