• Weed & Turfgrass Science
• /
• v.3 no.2
• /
• pp.110-113
• /
• 2014

The continuous use of acetolactate synthase (ALS) and acetyl-CoA carboxylase (ACCase) inhibitors has led to the selection of herbicide resistant barnyardgrass populations in direct-seeded rice fields of Korea. This study was conducted to identify herbicide resistant barnyardgrass biotypes and to determine the cross- and multiple-resistance of them. 25% of the population collected from Taeahn was partially resistant to ACCase inhibitors and 22% collected from Kimjae were partially resistant to ALS inhibitors. However, 8.2% of the population from both sites was resistant to ALS and ACCase inhibitors. Resistance to sulfonylurea herbicide, flazasulfuron was identified from two barnyardgrass accessions collected from both Taeahn and Kimjae. One barnyardgrass accession from both sites was resistant to ACCase inhibitor, sethoxydim. The cross-resistance to ALS inhibitors was identified at one barnyardgrass accession from Taeahn and at two accessions from Kimjae. Further, crossresistance to ACCase inhibitors was also identified at barnyardgrass accessions from Taeahn and Kimjae. Multiple-resistance to flazasulfuron and sethoxydim was determined at four barnyardgrass accessions from Taeahn and at six accessions from Kimjae. Therefore, the herbicide mixture and sequences within a growing season or the herbicide rotation with different modes of actions across growing seasons are recommended to control herbicide-resistant barnyardgrass in infested fields.

• Korean Journal of Soil Science and Fertilizer
• /
• v.46 no.2
• /
• pp.73-80
• /
• 2013

Due to the fact that possible risk associated with soil-crop-food chain transfer, metal contamination in croplands has become a major topic of wide concern. Accumulation of toxic metals in edible parts of crops grown in contaminated soils has been reported from number of crops including rice, soybean, wheat, maize, and vegetables. Therefore, in order to ensure food safety, measures are needed to be taken in mitigating metal pollution and subsequent uptake by crop plants. Present paper critically reviewed some of the cost effective remediation techniques used in minimizing metal uptake by crops grown in contaminated soils. Liming with different materials such as limestone ($CaCO_3$), burnt lime (CaO), slaked lime [$Ca(OH)_2$], dolomite [$CaMg(CO_3)_2$], and slag ($CaSiO_3$) has been widely used because they could elevate soil pH rendering metals less-bioavailable for plant uptake. Zn fertilization, use of organic amendments, crop rotation and water management are among the other techniques successfully employed in reducing metal uptake by crop plants. However, irrespectively the mitigating measure used, heterogeneous accumulation of metals in different crop species is often reported. The inconsistency might be attributed to the genetic makeup of the crops for selective uptake, their morphological characteristics, position of edible parts on the plants in respect of their distance from roots, crop management practices, the season and to the soil characteristics. However, a sound conclusion in this regard can only be made when more scientific evidence is available on case-specific researches, in particular from long-term field trials which included risks and benefits analysis also for various remediation practices.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.50 no.1
• /
• pp.60-66
• /
• 2005

Pod shape of twenty soybean (Glycine max L. Merrill) genotypes was evaluated quantitatively by image analysis using elliptic Fourier descriptors and their principal components. The closed contour of each pod projection was extracted, and 80 elliptic Fourier coefficients were calculated for each contour. The Fourier coefficients were standardized so that they were invariant of size, rotation, shift, and chain code starting point. Then, the principal components on the standardized Fourier coefficients were evaluated. The cumulative contribution at the fifth principal component was higher than $95\%$, indicating that the first, second, third, fourth, and fifth principal components represented the aspect ratio of the pod, the location of the pod centroid, the sharpness of the two pod tips and the roundness of the base in the pod contour, respectively. Analysis of variance revealed significant genotypic differences in these principal components and seed number per pod. As the principal components for pod shape varied continuously, pod shape might be controlled by polygenes. It was concluded that principal component scores based on elliptic Fourier descriptors yield seemed to be useful in quantitative parameters not only for evaluating soybean pod shape in a soybean breeding program but also for describing pod shape for evaluating soybean germplasm.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.52 no.4
• /
• pp.370-374
• /
• 2007

This study was carried out to investigate the soil chemical and physical properties by annul variation and yield properties according to cropping rotation system of paddy field which was cultivated rice and soybean of each 1 year by turns, each 2 year by turns, 1 year of rice and 3 years of soybean and 4 years of soybean continuously. This study was conducted for 3 years from 2002 to 2004 in National Institute of Crop Science(NISC), Korea. Study was controlled by Shinpaldal 2 of midmatured species, sow a field with soybean by $60{\times}15cm$ in 27 May. Chemical fertilizer was spread in the field by N 3.0 kg, $P_2O_5 $ 3.0 kg, $K_2O$ 3.4 kg per 10a. This experiment was carried for increase the degree of self sufficiency of soybean from detect the better cropping system in paddy field. The results of the study were as follows; Soil prosity was increased 17.4% in each one year rotation and 21.8% in the sector of cultivated soybean for four years. Results was indicated that $5{\sim}9cm$ of stem length, $0.5{\sim}1.0ea$ of branch number and $3.5{\sim}7.0$ of SPAD value was decreased in the sector of cultivated soybean for $3{\sim}4$ years compared to $1{\sim}2$ year cultivated sector. The soybean yield was reduced 12.9%(222 kg/10a) in the 2 year cultivated sector and 21%(201 kg/10a) in the 3 year cultivated sector compare with paddy-upland switching cultivation(255 kg/10a). Root nodule weight and number was tend to decrease according to the increasing duration of cultivated soybean.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.43 no.4
• /
• pp.245-249
• /
• 1998

Soybean [Glycine max (L.) Merr.), mungbean [Vigna radiata (L.) Wilcz.], cowpea [V. unguiculata (L.) Walp.], adzuki bean [V. angularis (Willd.) Ohwi & Ohashi], maize [Zea mays L.], sorghum [Sorghum bicolor (L.) Moench], sorghum $\times$ sudangrass [So bicolor intraspecific hybrid], and Japanese millet [Echinochloa crusgalli var. frumentacea (Link) W.F. Wight] were grown at two planting dates (18 June and 15 July) at Cheju in 1997 to select the best forage legumes adapted to Cheju Island for grass-legume forage rotation. Averaged across planting dates and cultivars, dry matter (DM), crude protein (CP), and total digestible nutrient (TDN) yields were 5,646, 1,056, and 3,637 kg/ha for soybean, 4,458, 676, and 2,661 kg/ha for mungbean, 3,289, 553, and 2,055 kg/ha for cowpea, 3,931, 674, and 2,489 kg/ha for adzuki bean, 12,695, 969, and 7,642 kg/ha for maize, 17,071, 1,260, and 8,857 kg/ha for sorghum, 16,355, 1,163, and 8,543 kg/ha for sorghum $\times$ sudangrass hybrid, and 8,288, 929, and 4,091 kg/ha for Japanese millet. Soybean was higher in CP, ether extract (EE), and TON content but was lower in nitrogen free extract content compared with the three other legumes. The legumes had much higher CP (13.7 to 21.9%), EE (2.42 to 6.23%), and TDN (58.7 to 69.9%) content but lower in crude fiber (CF) content (17.3 to 25.3%) than did the grasses tested except maize which had relatively lower CF content but higher TDN content. These results suggest that soybean could be the best forage legume for grass-legume forage rotation in the Cheju region.

• Korean Journal of Environmental Agriculture
• /
• v.28 no.4
• /
• pp.333-339
• /
• 2009

Various cultural practices have been promoted as management options for enhancing soil quality and health. The use of soil management methods can cause changes in fertility by affecting soil chemical properties. This study aimed to evaluate interactions between soil chemical properties and soil management methods in protected cultivation, and to classify soil management methods that similarly affect soil chemical properties. Water-logging and irrigation reduced soil pH and available $P_2O_5$ content. Application of animal manures has a positive effect on levels of organic matter, Av.$P_2O_5$, K, Zn, and Cu. The electrical conductivites tened to be low in the application of organic amendments, including rice and wood residues. Deeper plowing caused a reduction in Ca content. Practicing soil nutrient-considering fertilization and fertigation did not exert an influence on nutrient element contents. In a cluster analysis of the soil management methods according to major nutrients, low similarities were found with deeper plowing and crop rotation with rice in comparison with other practices. In a cluster analysis by minor nutrient characteristics, crop rotation and application of animal manures and rice residues were linked at a high Ward's distance, while other practices were found to be relatively low distinct. Each soil management method has a similar or different effect on soil chemical properties. These results suggest the necessity of establishing limits and standards according to the effects of soil management methods on soil chemical properties for economic soil practices.

• Research in Plant Disease
• /
• v.22 no.3
• /
• pp.184-189
• /
• 2016

To select resistant oil seed crops against two species of root-knot nematodes, Meloidogyne incognita and M. arenaria, 10 cultivars of sesame (Sesamum indicum L.) and 10 cultivars of perilla (Perilla frutescens var. japonica) were screened in greenhouse pot test. All sesame cultivars tested were resistant to M. incognita but susceptible to M. arenaria. While, perilla was resistant to both Meloidogyne species. Therefore, perilla cultivars could be used as rotation crop in greenhouse infested with both M. incognita and M. arenaria. But, sesame cultivars only can be used as a rotation crop in greenhouse infested with M. incognita but not for M. arenaria.

• Journal of the Korean Geographical Society
• /
• v.39 no.2
• /
• pp.171-194
• /
• 2004

The antebellum American South has been characterized by the lingering backward images of plantation, slaves and cotton. The South specializing in the cotton cultivation is compared with the manufacturing East and the breadbasket Midwest. Douglass North who examined the interregional trade assumed that the South up until 1860 relied on the Midwest for the foodstuffs. Statistical and literary evidence, however, disputes the North's model, showing instead that the southern region attained self-sufficiency in foodstuffs at least in the late 1830s or early 1840s. The South's food self-sufficiency is attributable, to a greater extent, to the region-wide environmental movement of scientific agriculture launched to address the aggravating soil problems from cotton monoculture. Diversification and crop rotation lied in the center of the new regime. The new agricultural system combining com, cotton and cowpea ensured the procurement of hoecake, hog meat, and cotton. The most significant outcome of the good farming regime, however, was the enhanced environmental consciousness which came to prevail the best farmer's reckless rush for profit maximization.

• The Korean Journal of Mycology
• /
• v.16 no.4
• /
• pp.220-225
• /
• 1988

This study was carried out to investigate the effect on the system of crop rotation of sesame(Sesamum indicum L). The results of infected plant percentage and yield of sesame wilting disease, fluctuation of density of Fusarium oxysporum and Actinomycetes, and their pathogenicity test on Fusarium spp isolated from sesame cultural soil were investigated. Density of F. oxysporum was the highest in a sesame continuous cropping soil but that of Actinomycetes was the lowest in that soil. And that of F. oxysporum and Actinomycetes according to investigation date was the highest at June. 30 and July. 30, respectively. Their pathogenicity of F. oxysporum and F. solani isolated from sesame cultural soil to sesame, peanut and green gram were recognized to all isolates except one isolate among F. oxysporum 8 isolates and one isolate to sesame, 2 isolates to peanut and all isolates to green gram among F. solani 4 isolates. F. oxysporum density and infected plant of wilting disease were increased as a result of replanted cultivation of sesame, and yield of that was prominantly reduced. Relation between density of F. oxysporum in cultural soil and infected plant percentage showed positive correlation and yield index highly negative. There was little difference between sesame-upland rice and sesame-peanut in the system of crop rotation.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.38 no.1
• /
• pp.46-54
• /
• 1993

On the purpose to increase the cultivation stability of the hulless waxy barley which is unstable in the northern region of Korea, the effects of genes of hulled /hulless and waxy /nonwaxy on seedling emergency was studied by using four isogenic lines of hulled -waxy, hulless -waxy, hulled -nonwaxy and hulless -nonwaxy barley. The germination rates of hulless lines lowered by four to six percent compared with those of hulled counterparts with one day's rainfall just before harvest, and were much deteriorated with raining prolonged. The gaps between emergency rates of hulless lines and their counterparts were greater than those of germination rates, and the differences increased as the seeding depths were deepened. The emergency rates of hulless lines were affected in the order of seeding depth, rotation speed of thresher and preharvest rainfall. Waxy endosperm gene did not show any significant effects on the damage of grain during threshing. It seems that the embryos of hulled lines were less damaged than those of hulless ones during threshing due to the protecting effects by husks. When grains were threshed with thresher of 600rpm or 900rpm and dehulled with dehuller of 750rpm, any significant depreciations such as broken seeds and decreased germination rate did not occured in hulled lines. But the grains of hulless lines received some damages with the rotation speeds, especially germination rates decreased seriously when the rotation speed of de huller was high. Prehavest sprout rates of the lines incorporated with the waxy genes were higher than those with nonwaxy genes whereas the genes of hulled and hulless did not give any significant effects.