• Korean journal of applied entomology
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• v.30 no.1
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• pp.50-53
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• 1991

The entomopathogenic nematodes, Steinernema carpocapsae and Heterorhabditis bacteriophoTa, were laboratory tested for the control of rice stem borer Chilo suppressalis. When 8 cm long of two rice stems infected by rice stem borers were treated with S. carpocapsae by spray application to the concentrations of 250, 500, 1,000, or 2,000 nematodes/ml, 68.6 $\pm$ 10.0-94.9 $\pm$ 2.6 % control was obtained. When 8 cm long of rice stems infected by rice stem borers were treated with H. bacteriophoTa by spray application to the concentrations of 100, 200, 400, or 800 nematodes/ ml, 91.4 $\pm$ 0.7-100 % control was obtained. On the other hand, when 8 cm long of three rice stems were treated with H. bacteriophora by dipping application to the concentrations of 100 or 200 nematodes/ml, 46.2 $\pm$ 4.7-63.1 $\pm$ 4.7 % control was obtained. Because the moist habitat of rice stems were favorable to nematode survival and searching abilities, entomopathogenic nematode, were confirmed to be a potential biological control agents against rice stem borers.

• Journal of Biosystems Engineering
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• v.16 no.1
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• pp.37-48
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• 1991

Rice plants are subjected to various forces such as natural force of wind and mechanical force of cultivating machines. Rheological behavior of the rice stem can be expressed in terms of three variables : stress, relaxation and time. The objectives of this study are to examine stress relaxation, creep and recovery characteristics on the rice stem in case of axial and radial loading. Stress relaxation with time was studied on three levels of loading rate and on four levels of applied stress. The results were summarized as follows : 1. The hysterisis losses of the rice stem distinctly observed at the radial compression in comparison with axial compression. The hysterisis loss implied that the stem to absorbed energy without being deformed beyond the yield point. 2. Ageneralized Maxwell model consisting of three elements gave a good description of the relaxation behavior of the rice stem. Rate of loading was more significant on the observed relaxation behavior within the short relaxation time, but there were little influences of rate of loading on the relaxation time. 3. The stress relaxation intensity and the residual stress increased in magnitude as the applied stress increased, but the relaxation time was little affected by the applied stress. 4. The coefficients of the stress relaxation model showed much differences in the radial compression and the axial compression, especially the higher relaxation stress of the third element was observed in the radial compression. 5. The behaviors of rice stem in creep and recovery test also might be represented by a four element Burger's model. But the coefficients of the creep model were different from those of the recovery model. 6. The steady-state phenomena of creep appeared at the stress larger than 20 MPa in Samkang and 1.8 MPa in Whajin. 7. The elastic modulus of the stem showed the range from 40 to 60 MPa. It could be considered, as a result, the rice stems had viscoelastic properties.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.1
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• pp.133-152
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• 2022

Rice is a fundamental staple food commodity all around the world. Globally, it is grown over 167 million hectares and occupies almost 1/5^th of total cultivated land under cereals. With a total production of 782 million metric tons in 2018. In Pakistan, it is the 2^nd largest crop being produced and 3^rd largest food commodity after sugarcane and rice. The stem borers a type of pest in rice and other crops, Scirpophaga incertulas or the yellow stem borer is very serious pest and a major cause of yield loss, more than 90% damage is recorded in Pakistan on rice crop. Yellow stem borer population of rice could be stimulated with various environmental factors which includes relative humidity, light, and environmental temperature. Focus of this study is to find the environmental factors changes i.e., temperature, relative humidity and rainfall that can lead to cause outbreaks of yellow stem borers. this study helps to find out the hot spots of insect pest in rice field with a control of farmer's palm. Proposed system uses temperature, relative humidity, and rain sensor along with artificial neural network to predict yellow stem borer attack and generate warning to take necessary precautions. result shows 85.6% accuracy and accuracy gradually increased after repeating several training rounds. This system can be good IoT based solution for pest attack prediction which is cost effective and accurate.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1262-1262
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• 2001

The rice plant is one of the important staple crops in Korea. The high yield with low cost in rice is required the soil fertility and the development of new precise method of fertilizer application by nutritional diagnosis. Now, in Korea, the nitrogen application system for the rice plant is composed of the basal fertilization, fertilization at tillering stage and fertilization at panicle stage, which the nitrogen fertilization at panicle stage amount to about 30 percent in the total amount. Thus, this experiment carried out to the development of the system that can measure the nitrogen content in the rice plant at panicle stage rapidly with the near infrared spectroscopy, and to predict the appropriate quantity of the nitrogen fertilization at panicle stage based on calibration model for test of nitrogen content in rice plant. The samples were collected from 48 varieties in 4 regions which are mainly cultivated in the southern part of Korea. And then, it collected by classifying into the leaf, the whole plant and the stem since 7 days before the nitrogen fertilization at panicle stage. The ranges of the nitrogen contents were 1.6∼4.0%, 1.7∼3.0% and 1.4∼2.7% in the leaf, the whole plant and the stem, respectively. In the calibration models created by each part of the plant under the Multiple Linear Regression(MLR) method, the calibration model for the leaf recorded the relatively high accuracy. The mutual crossing test on unknown samples were carried out using Partial Least Square(PLS) calibration model. That is, the nitrogen content in the stem was tested by calibration model made by the leaf model and that of stem was tested by calibration model made by whole plant sample. When unknown leaf sample was tested by calibration model made by all sample that collected from each part in rice plant such as leaf, stem and whole plant, it recorded the highest accuracy. As a result, to test the nitrogen content in the rice plant at panicle stage, the nitrogen content in the leaf shall be tested by the calibration model composed of the leaf, the stem and the whole plant. In future, to estimated the amount of nitrogen fertilization at panicle stage for rice plant , it will be calculated based on regression model between rice yield and nitrogen content of leaf measured by calibration model made by mixed sample including leaf, stem and whole plant.

• Journal of Mushroom
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• v.15 no.1
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• pp.21-24
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• 2017

In this study, the effect of different substrates of agricultural by-products on the mycelial growth rate and density of Trametes versicolor (Turkeytail mushroom) was analyzed. We found that pepper stem and rice bran with a mixing ratio of 9:1(v/v) produced the best mycelial growth of 101 mm in 10 days, while a mixing ratio of 8:2 resulted in mycelial growth of 83 mm in 10 days. The control group treated with a 9:1 mixing ratio of oak sawdust and rice bran (v/v) produced mycelial growth of 74 mm in 10 days. The following results are in the order of beanstalk, sesame stem, and perilla stem. After the harvest of the mushrooms, the mycelial growth rate and the density of T. versicolor in each substrate were as follows the group with waste substrate of Pleurotus eryngii and rice bran with a mixing ratio of 9:1(v/v) produced the best result of 76 mm in days, while a mixing ratio of 8:2 produced of 61 mm in 10 days. The control group with a 9:1 ratio of oak sawdust and rice bran produced mycelia of 74 mm in 10 days, while a mixing ratio of 8:2 resulted in mycelia of 59 mm in10 days.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.1
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• pp.29-35
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• 2009

The aim of the present study was to update the calibration that is used for the measurement of the total nitrogen content in the rice plant samples by using the visible and near infrared spectrum. Before the equation merge, correlation coefficient of calibration equation for nitrogen content on each rice parts was 0.945 (Leaf), 0.928 (Stem), and 0.864 (Whole plant), respectively. In the calibration models created by each part in the rice plant under the various regression method, the calibration model for the leaf was recorded with relatively high accuracy. Among of those, the calibration equation developed by Partial least squares (PLS) method was more accurate than the Multiple linear regression (MLR) method. The calibration equation was sensitive based on variety and location variations. However, we have merged and enlarged various of the samples that made not only to measure the nitrogen content more accurately, but also later sampling populations became more diversified. After merging, $R^2$ value becomes more accurate and significantly to 0.950 (L.), 0.974 (S.), 0.940 (W.). Also, after removal of outlier, R2 values increased into 0.998, 0.995, and 0.997. In view of the results so far achieved, Standard error of prediction (SEP) and SEP (C) were reduced in the stem and whole plant. Biases were reduced in the leaf, stem as well as whole plant. Slopes were high in the stem. Standard deviation reduced in the stem but $R^2$ was high in the stem and whole plant. Result was indicated that calibration equation make update, and updating robust calibration equation from merge function and multi-variate calibration.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.625-633
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• 1996

Crude extracts of 4 Allium SPP. such as welsh onion, onion, chinese chives and garlic were purified by paper chromatography and these activities were bio-assayed with rice seedlings. The stem and leaf slices of Allium spp. were treated and rice seedlings were planted in the soil to know the effect of its application on rice growth. The weak acidic fraction of Allium SPP. enhanced the growth and rooting of rice seedlings and had greater activity in promoting than in inhibiting the growth on rice seedling. Elongation of the second leaf sheath of the rice seedlings were not influenced by the extracts of Allium SPP. The stem and leaf application 10 days before transplanting, increased the number of effective tiller remarkably. Especially, the application of 50~400g welsh onion and 50~200g onions increased the number of spikelets per panicle compared to standard fertilization. But, in application of larger amounts, the-death rate of the rice seedlings after transplanting was higher in the stem and leaf application 10 days before transplanting than the one applied on the transplanting day. In particular, treatments of chinese chives and garlic showed higher death rate than those of welsh onion or onion. The stem and leaf application of Allium SPP. resulted in high yield than standard fertilization.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.6
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• pp.824-830
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• 2008

Sodium hydroxide (SH) or ammonium bicarbonate (AB) were applied to rice straw to investigate the effects on histological change of stem tissue or cell wall before and after in sacco degradation using a scanning electron microscope (SEM) and a transmission electron microscope (TEM). The SEM revealed that, the parenchyma and vascular bundles were distorted by treatment with SH at 30 or 45 g/kg straw dry matter. Faultage between phloem of large vascular bundles and parenchyma occurred with further increasing SH to 60 or 75 g/kg. The cell wall in these stem tissues was crimped when observed by TEM. However, only parenchyma and large vascular tissues were slightly distorted in AB-treated stem. For untreated and AB-treated stems, the initiation of observable ruminal degradation of cell wall was prolonged from 12 h for inner parenchyma to 24 h for sclerenchyma and to 48 h for phloem of small vascular bundles, while the outer epidermis was intact even at 72 h. For SH-treated stem, however, the cell wall from all of the investigated tissues, epidermis, small vascular bundles, sclerenchyma, and parenchyma started to be degraded at 12 h incubation. These results indicate that SH treatment contracts rice straw stem leading to an improvement in rumen degradation, and that the degradation of SH-treated stem is bilateral from inner and outer surface simultaneously.

• Korean journal of applied entomology
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• v.2
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• pp.38-43
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• 1963

1) These experiments were couducted to compare the effectiveness of with several new insccticides for the control of the rsce stem borer at Kimhae and Suwon in Korea from 1962 to 1963. 2) Gam ma-dol dusf and gramular were applied on the water surbul by hand and the other insecticides were sprayed on the leves of the paddy rice plaut by knap sack spayer(Table 1). 3) Gamma-dol was for the control of rice stem borers. more effective than other insecticidesused. timing for the applioation of$\gamma-dol$ was 10 days before hatching from the eggs. 4) There were no any significant differences in the effect of$\gamma-dol$ to the rice stem borer in both areas of Kimhae and Suwon.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.2
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• pp.61-65
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• 2011

Biomass is considered to be a major potential fuel and renewable resource for the future. In fact, there is high potential to produce the large amount of energy from biomass around the world. In this study, to obtain basic data for practical application of agricultural and forest by-products as fuel of heating system in agriculture, agricultural and forest biomass resources were surveyed, the pelletizer with capacity of $50\;kg{\cdot}h^{-1}$ was designed and manufactured and pellets were made by the pelletizer. High heating value, ash content, etc. of pellets made of agricultural and forest by-products were estimated. Straw of rice was the largest agricultural biomass in 2009 and the total amount of rice straw converted into energy of $299{\times}10^3$ TOE. And in 2009, amount of forest by-product converted into energy of $9,579{\times}10^3$ TOE. High heating values of pellets made of stem and seed of rape, stem of oat, rice straw and rice husk were 16,034, 16,026, 16,089, 15,650, $15,044\;kJ{\cdot}kg^{-1}$ respectively. High heating values of pellets made of agricultural by-products were average 83.6% compared to that of wood pellet. Average bulk density of pellets made of stem and seed of rape, stem of oat, rice straw and rice husk was $1,400\;kg{\cdot}m^{-3}$ ($1.4\;g{\cdot}cm^{-3}$). Ash contents of the pellets were 6.6, 7, 6.2, 5.5, 33% respectively. Rice husk pellet produced the largest ash content compared to other kinds of pellets.