• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.5
• /
• pp.779-786
• /
• 2012

Many farmers have been seeking alternatives to chemical fertilizer for successful organic fruit production. This experiment was carried out to investigate the replaceability of chemical fertilizer by cover crop and slurry composting biofiltration (SCB) liquid manure (LM) application in pear orchard. Three treatments were contained in this experiment; cover crop only and cover crop + LM treatment, and control (chemical fertilizer application). Dry weight and mineral contents of gramineous cover crops were significantly increased in LM-combined treatments than that of leguminous species. Bulk density of soil was decreased in rye + LM and hairy vetch + LM treatments, compared with each cover crop treatment. Soil pH was lowest in fertilizer treatment and soil nitrate content became similar between treatments after rainy season. Available soil phosphate was lower in cover crop and cover crop + LM treatmemts than control, but exchangeable Mg was higher. The mineral content and net assimilation rate of leaves showed no difference between the treatments. As a result, it is suggested that the application of SCB liquid manure in pear orchard managed by cover crops is desirable to maintain the productivity by improving soil physical properties and potential nutrient recovery.

• Korean Journal of Plant Resources
• /
• v.26 no.1
• /
• pp.1-8
• /
• 2013

This study was conducted to examine the relationship between cone abundance and cone/seed characteristics to improve seed quality and seed orchard management of Pinus koraiensis. The data was collected from P. koraiensis seed orchards at Chungju in 2007. That year was a rich year of cone harvest and the average number of cone per tree was 2.5 times much than that of normal year. We collected the cones from all trees in the sample plot of the seed orchard and investigated morphological characters such as cone length, cone width and cone weight. According to cone abundance per tree, the samples were divided into eight classes and analysed by cone analysis method. There is a decreasing tendency of number of fertile scale, seed potential, percent of filled seeds, seed weight per cone and seed efficiency, when the cone number per tree is increased. Additionally, the implications of the results to seed orchards management of P. koraiensis were discussed.

• Korean journal of applied entomology
• /
• v.43 no.3 s.136
• /
• pp.201-209
• /
• 2004

Overwintering ecology of the peach pyralid moth, Dichocrosis punctiferalis Guenee (Lepidoptera: Pyralidae) was studied in laboratory and in a chestnut orchard in 2001/2002 winter and 2003 spring. All twenty-four female and fourteen male moths were fruit-feeding type which were emerged from the larvae collected at the same chestnut orchard in 2003 winter. Periodical thermal treatment of overwintering larvae at $25^{\circ}C$ revealed that diapause termination of the larval population started from the end of January and was completed until April 20 in southern region of Korea. Pupation of diapause-terminated larvae started from early May and reached to $100\%$ at June 3 in chestnut orchard. Days to pupation of female larvae after diapause termination were 12.5, 8.9, and 7.5 at $20^{\circ}C,\;25^{\circ}C$, and $30^{\circ}C$, respectively. Those of male larvae were similar to those of females. Pupal periods of female were 14.7, 11.8, and 9.0 days at the three temperatures. Moths of the overwintered generation emerged from May 20 to June 28, and reached to $50\%$ emergence on June 8 to 9 under emergence cage. Attraction of the male moths of overwintered generation to sex pheromone traps showed that the date of $50\%$ catches to the traps were June 17, when data from 3 southern regions of Korea were pooled.

• Korean journal of applied entomology
• /
• v.47 no.1
• /
• pp.17-22
• /
• 2008

This survey was conducted from 1992 to 2005 in the major apple producing districts in southern part of South Korea including $4{\sim}8$ cities, to know the occurrence and damage level of two major pests, Carposina sasakii and Grapholita molesta that attack apple fruit. The fruit damage by G. molesta during the harvest period ranged from 0.02 to 1.64%. A tendency of higher damage of G. molesta was observed after 1997 compared with the previous years. The other hand, the fruit damage by C. sasakii was 0.02 to 1.30%, and the damage level was very low with fruit damage of < 0.3% except 1998. The orchard infested with G. molesta was 13 to 71 %, while 12 to 57% with C. sasakii. The rates of orchards where fruit damage by G. molesta was found were higher than those by C. sasakii after 1997. The tendency of fruit damage rates in the orchard where the most fruit damage was found was same with the trend of orchard rates infested with the pests. The maximum damage rate by G. molesta was 20.0% in 2005, while 4.5% by C. sasakii in 1998. The damaged shoot rates by the first generation G. molesta was $0.1{\sim}8.1%$, and it had a positive correlation with the rates of fruit damage during the harvest period. Consequently, it is concluded that G. molesta is dominant species compared with C. sasakii in commercial apple orchards recently.

• Journal of Korean Society of Forest Science
• /
• v.97 no.4
• /
• pp.398-407
• /
• 2008

This study is to give management state information about changes of income and net profit due to the fluctuations of chestnut prices to someone who will manage a chestnut orchard or has been managing a chestnut orchard in the market opening time. This study, hence, evaluated 133 households who manage a chestnut orchard at Jin-ju, San-cheoung in Gyeong-nam, Gu-rae in Jeon-nam, Gong-ju, Bu-yeo, and Cheoung-yang in Chung-nam. This study analyzed three scenarios by chestnut prices and by tree ages to provide informations for working expenses, production cost, income and net income to cultivators. In case of chestnut of one thousand won, the income of chestnut trees generated from nine ages and the net income is obtained from ten ages and turned into deficit from twenty-eight ages. In case of chestnut of one thousand and five hundred won, the income of chestnut trees generated from seven ages and the net income is obtained from nine ages. In case of chestnut of two thousand won, the income of chestnut trees generated from six ages and the net income is obtained seven nine ages. We calculated out labor costs and material cost and figured out management cost by tree ages. Namely two man and twenty woman are employed in harvesting 3,000 kg by hectare from ten till eighteen ages maximum harvesting seasons. Material cost is fertilizer cost, agricultural chemicals cost and seeding cost.

• Journal of Korean Society of Forest Science
• /
• v.97 no.3
• /
• pp.348-356
• /
• 2008

There is the need of regulating chestnut production because of being expected with chestnut trees cultivation farmhouses to be in a difficult situation by means of FTA negotiation promotion hereafter in Korea. And this study is aim to establish compensation criteria and plan for depreciation of income of farmers who take part in chestnut production regulation. We surveyed one hundred and thirty three among chestnut trees cultivation farmhouses in chief producing districts Kyung-nam, Jeon-nam and Chung-nam in Korea. As the result of this study, this study showed compensation criteria and plans for depreciation of income for farmers's participate in chestnut production regulation and showed criteria for closing chestnut old tree orchard and working process of cutting chestnut old tree. Procedures in closing chestnut old tree orchard in a day per hecta were felling operation and crude manufacture of thirty trees per one man, five forklains in loading and unloading chestnut log from a truck and building of workroad, the two number of assistance persons in loading and unloading chestnut log from a truck, the 6.94 trucks in carrying chestnut log. After farmers close chestnut trees orchard, government cost of old trees cuts and net income decrease for 3 years in case of planting trees for landscape and environment preservation.

• Korean Journal of Weed Science
• /
• v.4 no.2
• /
• pp.211-218
• /
• 1984

In order to establish the chemical weed control systems in orchard, field experiments were conducted to evaluate the effects of spray methods and mixing of herbicides. The mixtured dosage of glyphosate 100cc/10a and 2,4-D 75㏄/10a showed higher control effects than mono-treatment of glyphosate and paraquat on Artemisia vulgaris var. indica and Polygonum hydropiper L. And oxyfluorfen was more effective in reducing the cover rate and dry weight of weeds than simazine and alachlor on 75th day after treatment. In the mixing experiment of land and foliar appling herbicides. The effect of glyphosate on May 17 followed by oxyfluorfen on June 12 showed the best control effect.

• Korean Journal of Environmental Biology
• /
• v.37 no.4
• /
• pp.447-466
• /
• 2019

The orchard flora where perennial fruit trees are grown may be different than in arable fields where annual crops are grown. The study focused on the floristic composition and characteristics of orchards in South Korea. The flora surveys were conducted in 36 areas in nine provinces at two times (May-June and August-September) in 2014. The results showed that the vascular orchard plants in South Korea included 466 taxa, which contained 91 families, 278 genera, 420 species, two subspecies, 39 varieties, four forms, and one hybrid. Among the 91 families, Compositae was the most diverse in species (66 taxa), followed by Gramineae (51 taxa), Leguminosae (28 taxa), Cyperaceae (18 taxa), Polygonaceae (17 taxa), Cruciferae (16 taxa), and Labiatae (14 taxa). Based on the occurrence frequency of each species, Digitaria ciliaris (Retz.) Koel. (100%) was the highest, followed by Acalypha australis L. (94.4%), Commelina communis L. (94.4%), Persicaria longiseta(Bruijn) Kitag.(91.7), Capsella bursa-pastoris(L.) L. W. Medicus(91.7%), Erigeron annuus (L.) Pers. (91.7%), Mazus pumilus (Burm. f.) Steenis (86.1%), Artemisia princeps Pamp. (86.1%), Cyperus microiria Steud. (86.1%), Stellaria aquatica (L.) Scop. (83.3%), Stellaria media(L.) Vill.(83.3%), and Echinochloa crus-galli (L.) P. Beauv.(83.3%). The biological type of orchards in South Korea was determined to be Th-₅-D₄-e type. Rare plants were found six taxa: Cinnamomum camphora (L.) J. Presl, Aristolochia contorta Bunge, Melothria japonica (Thunb.) Maxim., Ardisia crenata Sims, Gnaphalium hypoleucum DC., and Aster koraiensis Nakai. Eighty-five taxa contained naturalized plants composed of 23 families, 58 genera, 80 species, four varieties, and one form. The urbanization and naturalization indices were 26.3% and 18.2%, respectively.

• Korean Journal of Environmental Agriculture
• /
• v.1 no.1
• /
• pp.1-13
• /
• 1982

Composite soil samples from 236 sites representing paddy field, up-land, orchard and plastic film house were examined for organochlorine residues by GLC-ECD. Detection frequencies and residual levels of most persistent organochlorine residues in the soil samples were found to depend on the cropping practices. Highest organochlorine residues were found in orchard soils and followed, in decreasing order, plastic film house, up-land and paddy field soils. ${\alpha}-Endosulfan$, dieldrin, p,p'-DDD and p,p'-DDT were responsible for the observed high organochlorine residues in the orchard soils. ${\alpha}-BHC$ and ${\gamma}-BHC$ were detected in all 236 soil samples. The mean residue levels of both BHC isomers were, however, remained fairly low. Residues of PCNB and ${\alpha}-endosulfan$ in native soils are reported, for the first time, in present work. PCNB was present in up-land plastic film house soils while ${\alpha}-endosulfan$ was found in all agricultural soils studied. High levels of p,p'-DDT and dieldrin were discussed in relation to crops cultivated, amount and duration of the pesticides usage. Need for continued observations on the persistent residue of pesticides in soils, already banned for general use, is emphasized.

• Korean journal of applied entomology
• /
• v.55 no.4
• /
• pp.483-487
• /
• 2016

The damage of citrus fruits caused by Scirtothrips dorsalis Hood has being increased in Jeju, Korea. The seasonal abundance of S. dorsalis and its injury symptoms in citrus orchards have been studied since the endemic outbreak in Jeju, but studies for the occurrence pattern of S. dorsalis in citrus orchards influenced by adjacent primary hosts have not been fully conducted yet. We selected kiwi- and mango-citrus adjacent orchards to study the migration pattern of S. dorsalis toward to citrus orchards. Yellow-colored sticky traps were used for monitoring the seasonal abundance of S. dorsalis and their migration pattern in two orchards. In citrus orchards, also, we placed sticky traps at 0, 5, 10, 15 and 20 m apart from the border of kiwi orchard, and 0, 7 and 20 m apart from the border of mango orchard. The seasonal occurrence pattern of S. dorsalis caught on sticky traps were similar between two adjacent orchards. However, the abundances in kiwi or mango orchard was much higher than those of citrus. Also, it was found that densities, distribution and damage of S. dorsalis in citrus orchards depend highly on the distance from the border of kiwi and mango orchards. This result suggested that the primary hosts such as kiwi and mango plants influence the occurrence of S. dorsalis in adjacent citrus orchards. And this information may provide a basic direction for establishing the management strategy of S. dorsalis in citrus orchards.