• Title, Summary, Keyword: lodging

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Algebraic Analysis for Partitioning Root and Stem Lodging in Rice Plant

  • Chang, Jae-Ki;Yeo, Un-Sang;Lee, Jeom-Sig;Oh, Byong-Geun;Kim, Jeong-Il;Yang, Sae-Jun;Ku, Yeon-Chung;Kim, Ho-Yeong;Sohn, Jae-Keun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.6
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    • pp.539-543
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    • 2006
  • Lodging is classified as root lodging caused by the loss of supporting force in the root, bending caused by the deformation of the stem and breaking where the stem breaks down as loads exceeding critical elasticity were applied. This research excluded breaking which is not in a state of equilibrium and tried to partition the level of lodging using an algebraic model in root lodging and stem lodging, or bending. When a vertical load was applied, the deformation of the stem of rice plant showed the form of a quadratic equation. The trace of the panicle neck in the process of lodging was an ellipse-shape. When loading was pure root lodging, the trace of the panicle neck became a circle of which culm length is the radius. When it was a pure stem lodging, the trace of the panicle neck is an ellipse of which major axis is culm length and minor axis is 0.64* culm length. When both stem lodging and root lodging occurred in a natural setting, the partitioning of lodging can be calculated by a formula using eccentricity of an ellipse, S=e*100/0.768(S is the ratio of stem lodging in the whole lodging, e is eccentricity of the ellipse). This method is expected to be useful in simple lodging partitioning. We could also calculate the partitioning of stem lodging and root lodging as units of angles as an accuracy method, by using a straight line calculated by differentiating a quadratic equation of stem deformation at the origin of the coordinates. These two methods for dividing root and stem lodging showed different values. However, each of them showed almost same values with different lodging degree in one plant.

Field Lodging Degree of Rice Varieties according to Nitrogen Application Rate (벼주요품종의 질소시비수준에 따른 도복저항성 정도)

  • 박중수;이원우;주영철;김영호
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47 no.3
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    • pp.226-235
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    • 2002
  • This experiment was to evaluate lodging characteristics of 35 recommended rice varieties of Kyonggi-do at normal (110 kg N/ha) and hen (220 kg N/ha) nitrogen application rates during 1999 to 2000. At heavy N fertilization rate, varieties that were highly resistant to lodging were Obongbyeo, Daejinbyeo, Naepoongbyeo, Nonganbyeo and Ilpumbyeo. Fourteen varieties including Daeanbyeo were moderately resistant and 11 varieties including Jinbubyeo were susceptible to lodging. The lodging-related characters which showed the highest effect on lodging at lodging degree of 9 were culm length and height of center gravity, culm length at lodging degree of 5, and culm length and the third internode length at lodging degree of 3 or below. The difference in rice yield between normal and heavy nitrogen fertilization rate was within 5% in early-maturing varieties but there was great yield difference in mid- and late-maturing varieties depending on the degree of lodging. Consequently, stable rice yield could be obtained by selecting lodging-resistant varieties and lowering fertilization rate, specially in the paddy field where lodging occurrence is common.

Relationships between Lodging and Root Characteristics of Soy bean Plants (대두의 도복과 근부특성과의 관계)

  • Je-Cheon Chae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.28 no.4
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    • pp.458-461
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    • 1983
  • The field experiment was carried out in order to find out the factors affecting lodging of Korean soybean varieties. Among the variety groups which were grown under the same cultural conditions, 25 Korean local varieties were selected by 5 lodging degree, and investigated their root characteristics in relation to lodging. The results obtained were as follows; There were no significant relationships between root dry weight, number of primary roots, number of adventitious roots and lodging. There also were no clear relationships between shoot/root weight ratio and lodging. However, it was recognized that the shoot weight/number of thick roots was highly related to soybean lodging. The susceptible varieties to lodging showed less shoot/thick root ratio.

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Effects of Seeding Dates on Lodging in Water Seeding of Rice (벼 담수표면 직파재배에서 파종기가 도복에 미치는 영향)

  • 송동석;김용재;이성춘
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.41 no.2
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    • pp.157-167
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    • 1996
  • The method of direct seeding on flooded paddy surface in rice is known to be the most labor saving cultural practice in rice. However, this method has a problem in practical use such as severe lodging occurring at the reproductive growth stage. The objectives of this study were observated degree of field lodging and variation of lodging-related characteristics with different seeding dates. The number of seedlings per m$^2$ were from 91 to 144 plants, and seedling ratios were from ranged from 61.7% to 91.8%. Days from seeding to flowering were shortened from 5 to 15 days by the later seeding dates. Heading dates of Ilpumbyeo, Seoanbyeo, Daecheongbyeo and Donjinbyeo on June 9 showed slightly elapsed on the critical stable heading time from, August 28 to 29. The culm length was effective in longer clum varieties than semidwarf varieties. The degree field lodging (degree of lodging: 0~9< 9 : complete lodging) in Obongbyeo and S101 with semidwarf varieties were 0.17, whereas 1.25 in Dongjinbyeo with long culm. The lodging resistant varieties and later seeding dates shortened the length of fibrous in the clum, and thickened fibrous in the clum, respectively. Obongbyeo and Sl0l showed stronger resistance to field lodging. The lodging resistant varieties, Obongbyeo and Sl0l, showed lower values of lodging index from 1.03 to 1.15 than those of lodging susceptible varieties, Daecheongbyeo and Palgongbyeo ranged from 1.42 to 1.70. Bending moment with leaf sheath were greater in lodging resistant varieties (Obongbyeo and Sl0l),1510.0~1930.4g.cm, than those in the lodging susceptible varieties (Daecheongbyeo and Palgongbyeo), 1127.2~1287.6g.cm.

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Varietal Difference of Lodging Occurence in Soybean Plant (대두 품종간 도복발생의 차이에 관한 연구)

  • Hong-Suk Lee;;Kwang-Ho Kim
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.27 no.3
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    • pp.254-260
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    • 1982
  • Ten soybean varieties were cultivated to know the varietal differences of lodging patterns of soybean plants under three different plant populations in two growing seasons in 1981. Lodging plant percentage was increased in higher plant populations and lodging responses to plant populations were different between soybean varieties. Lodging plant percentage was also increased by the growth of soybean plant and the patterns of lodging development along with the growth stages could be classified into four types by the varieties used, relatively lwoer iodging plant percentage from early to later growth stage but high in late and relatively high in middle stage but low in later stage. Williams, indeterminate type, and Kang-lim, determinate type, showed resistance to lodging under six different cultural practices, but Jang-yeop-kong, Dan-yeop-kong and Hwang-keum-kong showed resistance to lodging under specific cultural conditions among ten varieties used. Most of the plants lodged showed main stem bending in parts above first stem node in higher plant population and lodging resistant varieties showed lower frequency of stem bending lodging compared with those of lodging susceptible varieties.

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Characterization of Grain Quality under Lodging Time and Grade at Ripening (등숙기 도복 시기 및 정도에 따른 쌀 품질 특성)

  • Jeong Eung-Gi;Kim Kee-Jong;Cheon A-Reum;Lee Choon-Ki;Kim Sun-Lim;Brar Darshan-S.;Son Jong-Rok
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.5
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    • pp.440-444
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    • 2006
  • This study was carried out to compare the grain quality under lodging time and grade at ripening. Ripened grain ratio and 1000-grain weight were higher with lodging of plants at $45^{\circ}$ angle from the ground and increased with crop development. The number of spikelets, as well as the protein and amylose content of the grains, were higher in plants under severe or complete lodging than those under lodging at $45^{\circ}$ angle from the ground. Palatability and sensory evaluation values were higher in plants under lodging at $45^{\circ}C$ angle from the ground than those under complete lodging. Brown rice: rough rice ratio was higher with lodging of plants at $45^{\circ}C$ angle from the ground and increased with crop growth. Milling recovery and milled rice recovery were higher with lodging of plants at $45^{\circ}C$ angle from the ground, whereas chalky grain, cracked grain and damage grains were higher at complete lodging.

Relationship Between Lodging-Related Characteristics and Field Lodging in Rice (벼 도복 관련형질과 포장도복과의 관계)

  • 임준택;권병선;정병관
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.36 no.4
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    • pp.319-323
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    • 1991
  • To determine how closely related to field lodging for several characters affecting the field lodging for several characters affecting field lodging, and to obtain the basic information for selection of lodging resistance genotype, an experiment was conducted with 10 varieties from May to Oct., 1990 at the experimental field in Sunchon Xational University. Culm length, dry weight per unit culm length (W/1), bending moment per unit culm diameter (W1/d), lodging index (L), bending load ratio (W1/P), and index of critical lodging load(W$_{s}$$^{2}$/1$^4$) were the most closely related characters to field lodging. Culm length showed highly significant positive correlation coefficient with field lodging(r=0.7607), but it may be undesirable to judge lodging resistance of genotype by culm length itself without consideration of culm stiffness. Considering the difficulty and time-consuming to measure the character, clum length, W/1, W1/d, and W$_{s}$$^{2}$/1$^4$ were easy to measure and hence would be the most useful variables to judge the lodging resistance of genotype. Culm diameter, cross sectional area of culm, thickness of culm wall, and the second inertia moment of cross section of culm were not correlated with field lodging at all. Breaking strength of culm showed significantly negative correlation coefficient (r=-0.3986) with field lodging.ing.

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Changes in the Grain Quality of Rice with Respect to the Duration of Lodging Time

  • Hwang, Tai-Jeong;Lee, Won-Jong;Shin, Jin-Chul;Lee, Chul-Won;Kim, Suk-Shin
    • Food Science and Biotechnology
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    • v.18 no.6
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    • pp.1459-1463
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    • 2009
  • The specific objective of this study was to determine the changes in grain quality of lodged rice with respect to the duration of lodging time and compare the changes with those of unlodged one. The rice 'Janganbyeo' was cultivated and half of paddy field was totally lodged at 30 days after heading. Both lodged paddy and unlodged paddy were harvested at intervals and used for the grain quality determination. The lodged rice did not show any remarkable changes in grain quality until the $4^{th}$ day of lodging for rough rice and until the $2^{nd}$ or the $4^{th}$ day of lodging for brown rice and white rice. The overall grain quality of lodged rice could be kept for 2 to 4 days of lodging.

Effect of Planting Methods on Lodging Reaction in Lowland Rice (재배방법(裁培方法)이 벼 도복(倒伏)에 미치는 영향(影響))

  • Lee, Sang Chul;De Datta, S.K.
    • Current Research on Agriculture and Life Sciences
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    • v.7
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    • pp.11-21
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    • 1989
  • This experiment was conducted at the IRRI experimental fram, Los Banos, Philippines to determine the effects of planting methods on lodging in rice, and to determine plant characteristics that induce lodging. Moderately lodging-susceptible IR36, lodging-susceptible line IR21820-3-2-2-3 and lodging-resistant IR8 and IR64 were tested. Except in IR8, lodging resistance of all test rices was higher when transplanted than when broadcast-seeded. Transplanted rices yielded higher than did broadcast-seeded rices except with broadcast-seeded IR8. Yield reduction due to lodging varied from 0.6 to 1.5 t/ha. Yield components and vegetative characteristics did not differ significantly between planting methods. However, higher culm K content was observed in transplanted rice, and it consequently increased lodging resistance. Phosphorus ans Si contents did not significantly affect culm strength.

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Analysis of Lodging-Related Traits of Direct Seeded Rice

  • Kim, Hyun-Ho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.43 no.1
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    • pp.32-37
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    • 1998
  • The objective of this study was to analyze lodging-related traits using different cultivars from Korea, Japan, and the U.S. in direct seeded rice on dry paddy field. Stem diameter and culm wall thickness were highest in 'Caloro' followed by 'Nongan', 'M202', and 'Calrose'. All the U.S. cultivars were higher than the others in stem diameter and culm wall thickness. These two traits were important with regard to lodging. The highest breaking strength (1442g) was observed in Caloro. 'Gancheoek', 'Dongjin', and transplanted 'Hatsuboshi' showed more than 1000g in breaking strength. Lodging index was lowest in Hatsuboshi followed by Nongan and Gancheok. Even though breaking strength of the U.S. cultivars was higher than others, their lodging index values were high. There were no statistically significant differences in starch content. However, Calrose, Caloro, Dongjin, and Koshihikari were relatively higher than others in starch content. Positive correlations were found between culm base weight, lignin and breaking strength. High contents of lignin and cellulose were observed in Nongan, transplanted Hatsuboshi, Calrose, and Caloro. Traits such as stem diameter, culm wall thickness, bending moment, culm length, breaking strength, cellulose, lignin, and culm base weight were closely related to a lodging index. According to path coefficient analysis, most important traits were culm length, stem diameter, thickness of clum wall, and top plant weight.

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