• Food Science and Preservation
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• v.4 no.2
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• pp.131-137
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• 1997

Effect of storage on the tree and quality of early cultivar of Citrus unshiu Marc. produced in Cheju according to harvest time were investigated. Soluble solids, acid content, flesh ratio, firmness and specific cavity of the fruits harvested at 27th of November were 12.0, 1.03%, 79.98%, 0.774kg-force, 0.912, respectively. Soluble solids, total sugar and reducing sugar were increased gradually, but acid content was decreased slightly as delayed in harvest time. Otherwise specific gravity and firmness were not shown in great during harvest time, color index(a/b) was increased sharply till late November and then remained in stationary phase. On these result, we recommend that the harvest time of early cultivar of Citrus unshiu Marc. would be during December because of wilting partly. Fully ripened-fruits harvested late, compared to ordinary harvest time, with cold storage would be kept more quality and freshness of fruits for fresh consumption than the fruits harvested early and stored at room temperature.

• Proceedings of the Korean Magnestics Society Conference
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• 2014.11a
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• pp.170-170
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• 2014

• Proceedings of the Korean Magnestics Society Conference
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• 2012.05a
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• pp.81-81
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• 2012

• Journal of the Korean Society of Tobacco Science
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• v.19 no.2
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• pp.77-82
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• 1997

In order to investigate biochemical activities of harvested tobacco leaves, photosynthetic rate, soluble protein contents, and peroxidale activities were analysed during different maturing period. Physiological activities of harvested leaves during maturing period were higher in topped than those of non-topped plants. Chlorophyll content and photosynthetic rate in both topped and non-topped plants decreased at 4 days and 3 days before harvest, respectively. The chloroplast numbers in topped and non-topped plants decreased at 3 days and 5 days before harvest, respectively. Changes of soluble protein and total RNA contents showed similar patterns during maturing period. Soluble protein contents were slightly decreased from 5 days before harvest in topped plants, but decreased drastically from 3 days before harvest in non-topped plants. Not much changes were found in total RNA contents in topped plants until 2 days before harvest, and it was largely decreased after 5 days before harvest in non-topped plants. The peroxidase activities drastically decreased in topped plants and increased in non-topped plants after 3 days before harvest during maturing period. The largest change of biochemical activities in tobacco leaves during maturing periods were observed at 3 days before harvest.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.3
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• pp.164-168
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• 1995

A field experiment was carried out to determine the effects of nitrogen (N) fertilization levels after first harvest (0, 30, 60, 90 and 120 kglha) during spring season on the gms growth, dry matter (DM) yield, nutritive value, and efficiency of DM production per N kg applied in orchardgrass meadow. Additional N was applicated at early spring (70 kg), after second harvest (50 kg), and after fourth harvest (30 kg/ha) in all treatments, 1990. Growth and DM yield of orchardgrass at second harvest were significantly increased with increasing level of N after first harvest (P<0.05), but no yield differences were observed between application of N 60, N 90, and N 120 kg. The efficiency of DM increment per N kg applied was rapidly decreased with increasing level of N; that was 14.8, 12.0, 10.7 and 4.7 DM kg/N kgha in the plot of N 30, N 60, N 90 and N 120 kg, respectively. The content and yield of crude protein of orchardgrass at second harvest were significantly increased with increasing of N (P<0.05), ranged h r n 11.0% (N 0 kg) to 16.8% (N 120 kg), and from 195.0 kg (N 0 kg) to 508.2 kglha (N 120 kg), respectively. However, the content of neutral detergent fiber was not affected by N level after first harvest. From the above results, it is suggested that application of N fertilizer after first harvest was very effective for regrowth and nutritive value of orchardgrass during spring season, and the proper amount of N after first harvest was 60-90 kglha in this experiment.

• The Korea Journal of Herbology
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• v.34 no.2
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• pp.67-74
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• 2019

Objectives : Agastachis herba is a aerial part of Agastache rugosa (Fischer et Meyer) O. Kuntze which has been used as traditional medicines. Methods : The samples were collected using a domestic cultivation of Agastachis Herba. We experiment on essential oil content, the content of ethanol soluble extracts and HPLC profiling. Results : Loss on drying of Agastachis Herba contents of harvest in June ~ July was 4.93~8.26% and contents of harvest in August ~ September was 3.88~5.38%. Ash of Agastachis Herba contents of harvest in June ~ July was 5.07~7.97% and contents of harvest in August ~ September was 4.55~7.61%. Acid-insoluble ash of Agastachis Herba contents of harvest in June ~ July was 0.43~1.62% and contents of harvest in August ~ September was 0.46~1.44%. Essential oil contents of Agastachis Herba contents of harvest in June ~ July was $0.2{\sim}0.4m{\ell}$ and contents of harvest in August ~ September was $0.2{\sim}0.6m{\ell}$. Ethanol soluble extracts of Agastachis Herba contents of harvest in June ~ July was 9.72~20.44% and contents of harvest in August ~ September was 11.00~18.70%. HPLC profiling was detected of tilianin(12.93 min), acacetin(15.84 min) and agastachoside(17.95 min). Conclusion : Agastachis Herba should be harvested from August ~ September, the time of flowering. This is because of the high content of active compounds.

• East Asian mathematical journal
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• v.34 no.5
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• pp.683-691
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• 2018

We consider an optimal control problem for an impulsive stage-structured model involving ordinary differential equations with impulsive values of initial conditions in the next year. The main goal is to maximize a profit of the catch of Pacific cod in the South Korea through optimal harvest strategy as a control of adult cod. We established necessary conditions for the optimal harvest control using idea of Pontryagin's maximum principle. The optimal harvest strategy is to numerically solve the equation by using an iterative method with the Runge-Kutta method. Finally, we compare a monthly average of fishing mortality of Pacific cod from 2013 to 2017 with monthly fishing mortality for result obtained optimal harvest strategy.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.1
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• pp.75-80
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• 1996

The corn is one of the most important forage crop in Korea. The harvest time for silage affects dry matter (DM) yield and silage quality. This study was carried out to determine the effect of harvest time on the DM yield and nutritive value of corn forage at the Experimental Livestock Farm, College of Agriculture and Life Sciences, Seoul National University, Suweon in 1991. Forage DM yield and DM content of corn forage significantly increased mainly due to increase of ear. And also the ear to total DM ratio increased from 30% to 55% as the harvest was delayed. Chemical composition of the corn forage was improved by reduction in crude fihr, neutral detergent fiber and acid detergent fiber as the harvest was delayed. This results indicated that the harvest time of corn forage plays an important role to determine DM yield and DM contents for silage materials.

• ALGAE
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• v.27 no.1
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• pp.43-54
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• 2012

A mathematical model of the commercial harvest of Palmaria palmata (Dulse) is presented based on a logistic model and field data collected on Digby Neck, Nova Scotia from 14 harvested shores during May to August, 2010. Field observations used to estimate model parameters included cover of Dulse before and after harvest from Dulse dominated boulders for which surface area was estimated, and from which fresh biomass of harvested Dulse was weighed. Over all the surveys the average harvest fraction was about 50%, and the total resource was about $1,600g\;m^{-2}$. With growth rates in excess of 4% per day and a 50% harvest of the standing crop each month, the model suggests that the Dulse resource is sustainable at current harvest levels.

• ALGAE
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• v.27 no.1
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• pp.33-42
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• 2012

Population ecology of Palmaria palmata is described from the intertidal zone of Digby Neck and adjacent islands of Nova Scotia. The primary objectives were: to evaluate the difference in habitat specialization and population structure of P. palmata between harvest and non-harvest shores, and to characterize differences in thallus structure and frond sizes between epilithic and epiphytic populations. Harvest shores were gently sloping boulder fields with boulders typically about 0.5-1.0 m with dense cover of P. palmata on many of the rocks. Non-harvest shores (with or without P. palmata) consisted of boulders that were smaller or larger than harvest shores, or bedrock; when P. palmata was present on nonharvest sites it was typically epiphytic on other algae (e.g., Fucus spp., Mastocarpus stellatus, Devaleraea ramentacea). Harvestable epiphytic populations occurred only in high current areas. While there was little difference in average cover of P. palmata harvest and non-harvest shores ($31.2{\pm}13.7%$ vs. $19.4{\pm}7.3%$, mean ${\pm}$ standard deviation [SD]), the cover of P. palmata on harvest shores was highly skewed such that individual boulders often had >90% cover while adjacent rocks had little. Frond length of large fronds was greater on harvested shores, and mean frond density ($g\;m^{-2}$) was three times higher than the mean density on the non-harvested shores. Frond lengths of entire epiphytic and epilithic frond complements of 119 thalli from harvest beaches showed no difference in mean size of the largest fronds, and no difference in frond number per holdfast when epiphytic and epilithic thalli were compared.