• Journal of Wetlands Research
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• v.20 no.2
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• pp.131-135
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• 2018

Plants produce extrafloral nectar (EFN), liquid of carbohydrates to protect themselves against various insect herbivores through attracting natural enemy, ants, wasp and parasitoids, so EFN production is well known as one of indirect defense mechanisms. In many plants, EFN production is increased or induced when plants are attacked and damaged by insect feeding, whereas there are some plants whose EFN production is not altered or even decreased upon insect attack. The feeding types (chewing or sap feeding) of insects attacking plants also affect EFN production. The objective of this study was to examine how insect herbivore alters production of extrafloral nectar of Impatiens balsamina. Two different types of herbivores, leaf chewing and sap feeding insects, Spodoptera litura and Impatientinum impatiens respectively, are utilized. Plants were mechanically damaged by making holes on leaves with Jasmonic acid (JA) and regurgitate of S. litura added on. Two different densities of aphids were confined on leaves. The results of the study was that mechanical damage and JA or regurgitate addition did not affect EFN production in I. balsamina. Aphid feeding, regardless of density treated, decreased EFN production. The results of the study suggest that production of extrafloral nectar of Impatiens balsamina can be changed by insect feeding, and the effects of insect feeding can depend on the type of insects.

• Journal of Plant Biology
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• v.38 no.1
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• pp.47-54
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• 1995

The present study performed the isolation of cytosolic ascorbate peroxidase (APX) isozymes and analyzed the pattern of their activity development and also investigated the change in some other enzyme activities related to the ascorbate-glutathione pathway from the senescing wheat leaves. The aim of this work is to examine the possibility that in the cytoplasm of wheat leaves the ascorbate-glutathione pathway p!ays a significant role in relation to leaf senescence involving an $H_2O_2$ accumulation and then to show the effect of benzyladenine (BA) on that pathway. During the leaf senescence characterized by increases in ChI breakdown and H202 accumulation under the 4-day dark incubation of matured leaf segments; i) no significant increase of total cytosolic APX was observed, ii) a dehydroascorbate reductase (DHAR) activity was decreased rapidly, iii) a slight increase of glutathione reductase (GR) activity occurred. In the BA-treated leaves; however, i) the total activity of APX increased conspicuously, ii) the decrease of DHAR activity was relatively inhibited, iii) the GR activity increase was more enhanced, and iv) the decrease of ascorbate content and the increase of H202 content were retarded as compared with those of control leaves. Three isozymes of cytosolic APX were found by using a native-electrophoretic gel in senescing wheat leaves and two of them occurred with major activity. In the developmental patterns of cytosolic APX isozymes, only two isozyme bands ("a" and "b") appeared with almost constant activity through 4 days of incubation in the control leaves, while one additional weak isozyme band ("c") and a little increase of "b" isozyme activity were detected in the BA-treated leaves. EspeciaUy, the development of "a" isozyme activity increased remarkably compared with that of control leaves. The increased capacity for peroxide scavenging due to the enhanced activity of all 3 enzymes (APX, DHAR, GR) participating in the ascorbate-glutathione pathway in BA-treated leaves suggested that this pathway might playa significant role in the processes related to the wheat leaf senescence.scence.

• Korean journal of applied entomology
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• v.46 no.3
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• pp.425-430
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• 2007

Occurrence of Liriomyza trifolii and its biological control efficacy using Neochrysocharis formosa were evaluated in two eggplant cropping systems of spring and autumn cultivation. L. trifolii adults began to be attracted on a yellow sticky traps from late April and they increased from early June. A high density of L. trifolii adults was maintained from middle June to middle July. The releases of two N. formosa per plant with 3 times as weekly intervals from May 25, 2004 for spring culture resulted control effect of 90.1% in parasitism to L. trifolii in late July. The releases of two N. formosa per plant with 4 times as weekly intervals from August 31, 2004 for autumn culture resulted control effect of 81.3% in population of L. trifolii with 64.4-69.9% in parasitism.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.420-432
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• 2011

Population dynamics of greenhouse whitefly, Trialeurodes vaporariorum (Westwood), were modeled and simulated to compare the temperature effects of air and tomato leaf inside greenhouse using DYMEX model simulator (pre-programed module based simulation program developed by CSIRO, Australia). The DYMEX model simulator consisted of temperature dependent development and oviposition modules. The normalized cumulative frequency distributions of the developmental period for immature and oviposition frequency rate and survival rate for adult of greenhouse whitefly were fitted to two-parameter Weibull function. Leaf temperature on reversed side of cherry tomato leafs (Lycopersicon esculentum cv. Koko) was monitored according to three tomato plant positions (top, > 1.6 m above the ground level; middle, 0.9 - 1.2 m; bottom, 0.3 - 0.5 m) using an infrared temperature gun. Air temperature was monitored at same three positions using a Hobo self-contained temperature logger. The leaf temperatures from three plant positions were described as a function of the air temperatures with 3-parameter exponential and sigmoidal models. Data sets of observed air temperature and predicted leaf temperatures were prepared, and incorporated into the DYMEX simulator to compare the effects of air and leaf temperature on population dynamics of greenhouse whitefly. The number of greenhouse whitefly immatures was counted by visual inspection in three tomato plant positions to verify the performance of DYMEX simulation in cherry tomato greenhouse where air and leaf temperatures were monitored. The egg stage of greenhouse whitefly was not counted due to its small size. A significant positive correlation between the observed and the predicted numbers of immature and adults were found when the leaf temperatures were incorporated into DYMEX simulation, but no significant correlation was observed with the air temperatures. This study demonstrated that the population dynamics of greenhouse whitefly was affected greatly by the leaf temperatures, rather than air temperatures, and thus the leaf surface temperature should be considered for management of greenhouse whitefly in cherry tomato grown in greenhouses.

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.11a
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• pp.88-88
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• 2020

• Korean journal of food and cookery science
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• v.31 no.4
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• pp.510-514
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• 2015

Various parts of Kkujippong (Cudrania tricuspidata Bureau) tree (leaves, stems, roots, and fruit) were evaluated to determine their properties. The general components of Kkujippong tree were fat 1.3-5.9 g /100 g, protein 6.3-18.7 g /100 g, and ash 2.8-9.0 g /100 g. The fiber content of the stem was the highest amount at 69.2 g/100 g, followed by protein in the roots (49.9), leaves (45.5), and fruit (15.6). In addition, Kkujippong tree was found to contain high concentrations of several minerals (Ca, Fe, Mg, Na, P, Zn) in the leaves. The total polyphenol content was significantly higher in the leaves than in other areas at 571.3 mg% (p<0.05). Electron donating ability was also highest in the leaves at 83.55% (p<0.05).

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.441-450
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• 2013

The purpose of this study was optimization of the conditions for mixing different amounts of red radish (Raphanus sativus L.) sprout powder, butter, and sugar when baking domestic wheat cookies prepared using red radish sprout powder. Response surface methodology, with a central composite design comprising 5 levels and 3 variables, was used to identify the best possible combination of amounts of red radish sprout powder ($X_1$), butter ($X_2$), and sugar ($X_3$). The physical and mechanical properties of each of the 20 samples analyzed, including color L (p<0.001), color a (p<0.01), color b (p<0.001), spread ratio (p<0.001), and hardness (p<0.01), differed significantly. The results of sensory evaluations, including color (p<0.001), appearance (p<0.001), texture (p<0.001), flavor (p<0.01), taste (p<0.001), and overall quality (p<0.001) also differed significantly among the samples. The optimal compositional ratios were 5.15 g for the red radish sprout powder, 64.84 g for the butter, and 47.18 g for the sugar.

• Journal of Korea Foresty Energy
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• v.25 no.2
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• pp.28-33
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• 2006

This study was conducted to find potentialities of the leaves of gingko tree (Gingko biloba L.) which has been planted as a roadside tree in Korea because of its resistance on air pollution, insect, fungi, etc. Various amounts of the leaves were mixed with wasted wood particles to manufacture particleboard. Their influences on physical and mechanical properties and the formaldehyde emission of PB were investigated. Physical and mechanical properties, such as density, modulus of rupture (MOR), and internal bond (IB) strength, of manufactured particleboard were not much different from those of control board. Formaldehyde emission values were decreased with increasing amount of leaves in PB prepared. Especially, particleboard made with 3 percent of leaves was decreased to $1.66mg/{\ell}$ in formaldehyde emission, which is about 40% lower emission than that of control. From these results, the leaves of gingko tree may be considered as a formaldehyde emission lowering additive in a functional PB manufacturing process.

• Food Science and Preservation
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• v.8 no.4
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• pp.469-474
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• 2001

Chemical composition of the water extract of three different kinds of bamboos was investigated to access nutritive sources. Bamboo stalks and leaves were extracted massively and concentrated to 3°Brix, and crude protein and fat contents of the extracts were respectively 0.56∼0.69% and 0.28∼0.58%. Main mineral contents of the extracts were K, P and Mg in order, and those were the highest in Wangdae stalks. In free sugar analysis of the extracts, Maengjongjuk stalks contained 1.1% sucrose, Somdae stalks contained 0.51% fructose and Wangdae stalks contained 0.6% glucose as the highest level. Organic acid contents of the extracts showed high level in acetic and malic acid which were 54.0 and 44.2mg% in extracts of Wangdae stalks respectively. Among amino acids, aspartic acid was contained the highest level in stalk extracts, and their concentrations were 42.2, 39.9 and 34.6mg% in Wangdae, Somdae and Maengjongjuk respectively. In leaf extracts, glutamic acid concentrations were higher than the other amino acids, and those were 19.3, 18.5 and 15.7mg% in Maengjongjuk, Wangdae and Somdae, respectively.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.05a
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• pp.295-297
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• 2023

채식이 점차 보편화되어감에 따라 소비자를 만족시키기 위한 양질의 작물 생산 및 신품종 개발 필요성도 커져가고 있다. 이 때 식물의 건강 상태나 당도, 식감 등의 품질 조사를 위해서는 표현형 데이터 획득이 필수적이다. 표현형이란 식물의 잎과 줄기, 과실 등에서 겉으로 드러나는 형질을 의미하며, 잎맥밀도도 중요한 표현형 중 하나이다. 하지만 이를 연구자가 수작업으로 조사할 경우에는 시간과 노동력 소모가 크며 측정 인력이나 측정 환경에 따른 오차도 큰 문제점이 있다. 따라서 본 연구에서는 디지털 기술을 통해 잎 이미지에서 잎맥을 추출하여 잎맥 밀도를 분석하는 시스템을 구현함으로써 작물 생산 자동화 및 신품종 개발 효율성 향상에 기여하고자 한다.