Chlorophyll is an essential pigment involved in light absorption and electron transfer in photosynthesis, a photochemical process that is indispensable for plant growth and development. The biosynthesis of chlorophyll occurs in plastids and shares a common biosynthetic pathway with other tetrapyrroles. The chlorophyll metabolic pathway is divided into four distinct components: the common pathway, chlorophyll-specific biosynthetic pathway, chlorophyll cycle, and chlorophyll degradation pathway, which are regulated in developmental- and environmental-specific manners. During the early stages of plant growth, the expression of most chlorophyll biosynthetic genes is induced by light, resulting in an increase in chlorophyll accumulation, induction of high photosynthetic activity, and continuous plant growth. In contrast, during plant maturation, the expression of most of these genes is gradually downregulated, whereas genes involved in chlorophyll degradation are upregulated during leaf senescence. Chlorophyll biosynthesis is directly or indirectly regulated by the members of various transcription factor families. In this review, we describe representative mechanisms of transcription factor-mediated activation and repression of chlorophyll biosynthesis in response to light treatment. We also present an overview of recent studies that have examined all the enzymatic steps involved in chlorophyll metabolic pathways and their gene regulation at the transcriptional level, which will enable readers to gain a better understanding of chlorophyll metabolism.
Given that soil salinity significantly limits plant growth and production in agricultural land, research on salt stress is of particular agricultural relevance. In this study, for the purposes of functional screening of genes involved in salt stress responses, we selected approximately 651 transgenic
In this study, conducted in living modified organism (LMO) isolation fields, we sought to develop environmental risk assessment procedures for identifying the potential effects on non-target above-ground insects and spiders within agroecosystems cultivated with vitamin A-enhanced transgenic soybean with tolerance to the herbicide glufosinate. To this end, we investigated insect/arachnid species diversities and population densities on vitamin A-enhanced transgenic soybean and non-GM soybean (Gwangan) grown in LMO quarantine areas of Kyungpook National University (Gunwi) and the National Institute of Agricultural Sciences (Jeonju). In total, 93,419 individual insects and arachnids, representing 65 families in 12 orders, were captured during the study. In Gunwi, totals of 17,110 and 17,627 individual insects and arachnids were collected from vitamin A-enhanced transgenic soybean and Gwangan, respectively, whereas in Jeonju, totals of 28,621 and 30,061 individuals were collected from vitamin A-enhanced transgenic soybean and Gwangan, respectively. Although we detected no significant differences among the population densities of insect pests, natural enemies, and other insects on vitamin A-enhanced transgenic soybean and Gwangan grown within the same field, the population densities of these insects were found to be higher in Jeonju than those in Gunwi. Throughout the study, analysis of variance indicated no significant differences (
The purpose of this study was to examine the potential utility of marker-assisted selection (MAS) based on storability-associated molecular markers in apple breeding and to provide genotype information for the markers
Rice doubled haploid (DH) lines derived from crosses of the
In order to select sweetpotato varieties with excellent tip characteristics, we investigated the appearance, yield, and functional compounds in 32 domestic sweetpotato varieties. During the cultivation period, the total production of sweetpotato tips among the different variety ranged from 1,780 to 9,923 g/m2, with that of the Gogeonmi variety being the highest. The lutein content among varieties ranged from 21.7 to 47.0 mg/100 g and was highest in the Juhwangmi variety, whereas the ß-carotene content ranged from 25.5 to 183.4 mg/100 g and was highest in the Hayanmi variety. The total polyphenol content ranged from 30.7 to 74.4 mg CAE/g, and it was high in the Pungwonmi, Daeyumi, and Dahomi varieties at 74.4, 73.8, and 72.9 mg CAE/g, respectively, whereas the DPPH radical scavenging activity of tips ranged from 88.6% to 91.6%, with Gogeonmi and Healthymi showing the highest value of 91.6%. ABTS radical scavenging activity was found to be lowest in the Yeonjami variety at 86%, whereas the remaining 31 varieties showed values in excess of 96%. ABTS radical scavenging activity showed a high positive correlation with total polyphenol content. On the basis of these analyses, we identified Juhwangmi with high lutein content, Hayanmi with high beta-carotene content and high yield, and Gogeonmi with high DPPH radical scavenging activity and high yield, as being suitable varieties for tip cultivation. We anticipate that these sweetpotato varieties with excellent tip characteristics will be used as parents for the breeding of varieties for vegetable use.
Recent climate changes have resulted in high temperatures, a greater frequency of flooding, and outbreaks of various plant diseases and insect pests, the latter of which has been characterized by a change in pest type from crop chewing to sap-sucking insects. To date, however, there has been limited study of plant resistance to sap-sucking insects. This study was carried out to evaluate the resistance and genetic patterns of the foxglove aphid
Kernel weight is a vital trait for selecting high-yielding wheat in breeding programs. We evaluated the thousand-kernel weight (TKW), test weight (TW), grain length (GL), grain width (GW), grain thickness (GT), and grain roundness (GR) of 41 Korean winter wheat cultivars over a period of 4 years. Correlation analyses revealed that TKW was positively correlated with GL (r=0.76***), GW (r=0.85***), and GT (r=0.84***), whereas TW was negatively correlated with GL (r=-0.38*) and GT (r=-0.31*). Allelic variation was analyzed for 13 kernel weight-related genes/loci (
Marker-assisted backcrossing is a powerful method for developing new cultivars. To develop genomic-wide markers, genotyping-by-sequencing (GBS) can be an efficient method. However, unrefined low-quality markers and missing data between markers can contribute to hampering the marker selection process, particularly in multi-way crosses. In this study, we aimed to calculate the recovery rate of offspring individuals and minimize errors that occur among a large number of markers. Initially, missing data were imputed by comparing samples using the
The regeneration rate of plantlets cultivated via tissue culture is an important factor for wheat transformation. Similar to other monocotyledons, the most efficient tissue culture materials for wheat are immature embryos. However, stable year-round production of immature embryos is not possible in the field where various stress factors co-exist. In this study, we investigated the generation and subsequent plantlet incident rates of callus induced from immature embryos obtained from different sowing times in 2020 and compared these among wheat cultivars. We found that the rates of regeneration and plantlet incidence obtained using immature embryos of the Ariheuk cultivar were higher than those of other domestic cultivars, and that the tissue culture efficiency was similar to that of Bobwhite, which has been established as a cultivar with excellent transformation efficiency. Furthermore, the Baekkang cultivar showed high tissue culture efficiency only when sown from early to mid-March, whereas Keumkang showed higher tissue cultivation efficiency only by sowing in mid- and late February. Among the five cultivars assessed in this study, Jopum showed the lowest tissue culture efficiency. It is anticipated that the findings of this study will contribute to enhancing the transformation efficiency of domestic wheat varieties.
Recent advances in high-throughput sequencing technologies have enabled large-scale cost-effective genotypic analyses, and consequently, obtaining reliable phenotypic data has now become a major bottleneck in data-driven plant breeding. In order to construct a phenotype database for commercial rice varieties released by the National Institute of Crop Science, Rural Development Administration, we initiated a systematic phenotype evaluation project, with the aim of investigating the major agronomic traits of Korean rice varieties released during the period between 1979 and 2017. Despite the narrow genetic background, we found that the days to heading (DTH) and culm length (CL) of the 297 Korean rice varieties assessed exhibited wide phenotypic variation under different environments. Under normal planting cultivation in 2018, the DTH ranged from 48 to 104 days in Suwon, 46 to 111 days in Wanju, and 39 to 97 days in Miryang, with CL values ranging from 59 to 134 cm, 55 to 122 cm, and 57 to 106 cm, respectively. During early planting cultivation in 2019, the DTH ranged from 56 to 113 days (Suwon), 58 to 109 days (Wanju), and 58 to 100 days (Miryang), with corresponding CL values ranging from 63 to 119 cm, 55 to 93 cm, and 51 to 115 cm. Despite the difference of one month in planting dates in 2018 and 2019, DTH in the different years and regions showed highly significant positive correlations (r=0.90-0.98), whereas CL showed positive but weaker correlations (r=0.45-0.82). Furthermore, we detected a weak, although significant, correlation between DTH and CL in each environment (r=-0.18-0.35). Analyses of additive main effects and multiplicative interaction (AMMI) were conducted for DTH and CL to identify rice varieties with stable phenotypes under different environments. We anticipate that the findings of this study will provide a useful rice phenotype database to facilitate genotype-phenotype association studies and data-driven rice breeding.
Phytophthora root rot attributable to infection by the soil-borne oomycete
This study was performed to evaluate the characteristics of wheat flour and sourdough bread quality of five Korean bread wheat cultivars, hard red winter wheat (HRW), and T55 (a French commercial wheat flour). Among the cultivars assessed, the protein and gluten contents and SDS-sedimentation values of Joongmo2008 were the highest, Keumkang were similar to those of HRW, and those of the Baekkang, Jokyung, and Hwanggeum were similar to those of T55. Joongmo 2008 and Keumkang had glutenin contents similar to those of HRW and T55, whereas Baekkang and Hwanggeum had higher HMW-GS (high molecular weight-glutenin subunit) and lower LMW-GS (low molecular weight-glutenin subunit) contents than HRW and T55. The
In this study, 14 agricultural and phenotypic traits were used to analyze morphological variations among 10 near-isogenic lines (NILs) of colored waxy maize and 2 parental lines (HW3 and HW9) of the hybrid cultivar “Mibaek 2.” The results of principal component analysis indicated that on the first principal component axis, seed coat color, R value, V value, days of tasseling, L* value, and days of silking greatly contributed to the positive direction, whereas anthesis–silking interval and leaf width greatly contributed to the negative direction. On the second principal component axis, kernel row number and tassel color contributed to the positive direction, whereas setted ear length, ear length, and 100-kernel weight contributed to the negative direction. Thus, the morphological characteristics that greatly contributed to the first and second principal components might be useful for discrimination among the 10 NILs and 2 parental lines of “Mibaek 2.” Of the 10 NILs analyzed, 16CLP26 and 16CLP16 were considered useful breeding material for the development of colored waxy maize varieties with relatively high amounts of yield and anthocyanin. Collectively, these results are expected to provide useful information for the development and selection of lines for breeding colored waxy corn varieties at the Maize Research Institute, Gangwon-do Agricultural Research and Extension Services.
‘Taecheong’ is a black soybean cultivar developed from crossing ‘YS1593(Milyang136×Tanbaguro)’ and ‘Cheongja2’ in 2005. F1 and F2 populations were grown for 2 years and promising lines were selected by pedigree method from F3 to F5. The preliminary yield trial (PYT) and advanced yield trial (AYT) were conducted from 2012 to 2013, and a regional yield trial (RYT) in seven regions was conducted from 2014 to 2016. ‘Taecheong’ is determinate, with purple flower, green cotyledon, and black spherical seed. Flowering date and maturing date were August 3 and October 20, respectively. Regarding quantitative characteristics, ‘Taecheong’ has a larger seed size (44.5 g/100-seed weight) than that of ‘Cheongja3’ (35.8 g/100-seed weight). ‘Taecheong’ was tolerant to pod shattering and lodging at the RYT field and indoor test. In addition, ‘Taecheong’ was resistant to bacterial pustule during the field test, and to soybean mosaic virus (G6H strain) during the inoculation test. Although its seed quality-related characteristics were similar to those of ‘Cheongja3’, it contained more anthocyanin in its seed-coat, which is a primary functional component of black soybean. The mean yield of ‘Taecheong’ in RYT was 240 kg/10a, which was 94% of the yield of ‘Cheongja3’. ‘Taecheong’ is expected to be used as raw material for soy products, such as for preparing soybean chocolates, because of its large seed size (Registration number: 7104).
We developed a malting barley, ‘Dapum’, with stable yield and enhanced quality for brewing. ‘Dapum’ was developed in 2015, by crossing Hopum, which has high brewing quality, and ‘GobDH96’, which has steady yield. The regional yield trials were conducted for ‘Dapum’ as a breeding line ‘Iksan173’ in four different regions from 2013 to 2015. It has a type I growth habit, and the average heading and maturing date in paddy fields were April 20 and May 26, respectively, which were 1 day earlier than those of ‘Hopum’. The yield potential of ‘Dapum’ was 411 kg/ha, which is approximately 10% higher than those of ‘Hopum’ under paddy field condition. ‘Dapum’ possesses the
‘Sangbo’ is a japonica rice (
A new six-rowed covered barley cultivar ‘Hohyang’ with spring sowing adaptability, lodging tolerance, and high yield was developed from the cross between ‘Saegangbori’ and ‘Durubori’ by the National Institute of Crop Science, RDA, Korea, in 2016. It has a compact spike and long awn, and its growth habit (vernalization requirement) was classified as group II. The averaged heading date was April 21, which was 1 day earlier than that of the control varietal, ‘Olbori’. The culm length was 78 cm, which was similar to that of ‘Olbori’; however, ‘Hohyang’ has a stronger lodging tolerance. Its spike length was 4.7 cm, 655 spikes/m2, 55 grains/spike, and 31.9 g for 1,000 grains. It also showed similar winter hardiness and a superior resistance to barley yellow mosaic virus (BaYMV) compared to that of ‘Olbori’. ‘Hohyang’ was well adapted to spring sowing conditions from March 6 to April 3. Regarding quality, ‘Hohyang’ had the same protein and
A new interspecific hybrid cultivar, Wongam, was developed as a high-yield licorice from a
A new double cropping potato variety, ‘Gangseon’, was bred by the Highland Agriculture Research Institute, National Institute of Crop Science (NICS), RDA, Korea, in 2016. ‘Gangseon’ was obtained from the cross between ‘Daegwan1-83’ and ‘Chubaek’ in 2006. Seedling and line selection was performed from 2008 to 2009, and preliminary and advanced yield trials were carried out with ‘Gangseon’ from 2010 to 2013 in Gangneung city. The regional yield trials were conducted in Gangneung, Muan, and Jeju from 2014 to 2016. ‘Gangseon’ has light purple flowers, green narrow leaflets and petioles with medium anthocyanin coloration, round tubers with yellow russet skin, and yellow flesh. The dormancy of ‘Gangseon’ stored in 20 ℃ was 60-70 days after harvesting, which is longer than those of ‘Dejima’ and ‘Chubaek’, but shorter than that of ‘Superior’. The average yields of tubers in the spring and fall seasons were 36.6 and 21.2 ton⋅ha-1, respectively, in the regional yield trials. It is susceptible to common scab and potato virus Y, but has high resistance to potato leaf roll virus, potato virus X, early blight, and late blight. The dry matter contents were 22.1% in spring and 19.8% in autumn. The adaptation area of ‘Gangseon’ is the southern coastal area, including Jeju Island, Korea. The plant variety protection right of ‘Gangseon’ was registered in April 2020, and its grant number is 8081.
‘Hwanggeummatchal’, a yellow waxy corn hybrid obtained by crossing inbred ‘KY37’ and ‘KY29’, was developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA, Korea, in 2017. The number of days to silking of ‘Hwanggeummatchal’ was 69 days after planting, 2 days earlier than ‘Ilmichal’ (a control variety). Plant height of ‘Hwanggeummatchal’ was 205 cm, lower than that of the control, and ear height ratio was 49%, which was lower than that of ‘Ilmichal’. Lodging resistance of ‘Hwanggeummatchal’ was similar to ‘Ilmichal’. The fresh ear yields were 6,389 ears in 10 a. The carotenoid content of ‘Hwanggeummatchal’ was 16.4
The cultivation of early maturing rice in the plain areas in Korea is increasingly diversifying its cropping systems. Early maturing rice cultivars are usually vulnerable to bacterial blight (BB) and rice stripe virus (RSV) compared to mid- and mid-late maturing rice cultivars. To enhance the resistance of early maturing rice against BB and RSV, ‘IS592BB’ was developed by introgression of resistance genes,
A new persimmon (
A small red bean cultivar, ‘Haeorom’, was developed by artificial cross breeding between ‘Milyang 7 (SA9709-2B-8-2-4-4-1)’ and ‘Toyomidainagon (K204656)’ at the National Institute of Crop Science, RDA, Korea in 2008, and selected for further yield trials under the name ‘Miryang 27’. It was prevalent and showed desirable agronomic traits such as lodging tolerance, high yields, and strong antioxidant activity during the regional yield trials (RYT) from 2014 to 2016. ‘Haeorom’ was released as a new cultivar in 2016. It has some distinct phenotypic traits, including a semi-determinate growth habit, yellow flower, green embryonic axis, bright red seed, white hilum, and small spherical seeds (18.6 g per 100 seeds). The average yield of ‘Haeorom’ was 2.04 MT/ha in the RYT, which was slightly higher than that of the check cultivar (1.87 MT/ha), ‘Chungju’ (Registration No. 7508).
‘Jangsuheukchal’ waxy corn was developed through single-cross by Gyeonggido Agricultural Research and Extension Services in 2012. The seed parent inbred ‘GMB0016’ was crossed with the pollen parent inbred ‘GMB0017’ in 2010. ‘Jangsuheukchal’ took 72 days to silking, which was 4 days sooner than ‘Miheukchal’, and ‘Jangsuheukchal’ was 195 cm in height, which was 12 cm less than that of ‘Miheukchal’; the occurrence of lodging was low in the new species. Among the ear characteristics, the kernel setting rate was very high (99%), and the grain pericarp thickness was slightly more than that of ‘Miheukchal’, but the sensory evaluation was positive because of the high amylopectin content and the fine ear appearance. The regional yield trials were conducted in four areas for two years in 2011-2012, and the density of fresh ears for ‘Jangsuheukchal’ was determined as 62,280 ears/ha, which was 6% higher than that of ‘Miheukchal’, but the weight of the fresh ears was 9,178 kg/ha, which was 17% lighter than its counterpart. In order to diversify the use of fresh waxy corn, the cooking properties of milled waxy corns were investigated and compared to ‘Mibaek2’, which was the main cultivar in Gyeonggido province in 2018. The grain yield per ha of ‘Jangsuheukchal’ was 5,600 kg, which was 12% less than that of ‘Mibaek2’, but after harvesting fresh ears, the grain yield per ha was 1,060 kg, which was 10.6 times more than the known cultivar. In addition, compared to ‘Mibaek2’, ‘Jangsuheukchal’ showed excellent processing characteristics in the cooking properties for milled kernels because of its light 100-seed weight, low protein content, and high starch content. Therefore, we report ‘Jangsuheukchal’ as a new variety, suitable for use as a fresh corn and possessing the cooking properties of milled kernels (Registration No. 6065).
‘Shingil’ was developed as a processing rice for specialization as a rice flour by means of mutation breeding from ‘Hanareum’ MNU (N-methyl N-nitrosourea) treatment. The bulk population was displayed from M1 to M6, followed by pedigree methods from M7, where line selection was carried out based on the amylose content, with opacity in the endosperm. The result was that ‘Milyang317’, which has a somewhat high amylose content as well as a high ratio of starch opacity, was selected and named as ‘Shingil’ in 2017. ‘Shingil’ is a mid-maturing ecotype with a heading date of August 10, showing resistance to both leaf/panicle blast and rice stripe virus (RSV), but susceptibility to Bph. ‘Shingil’ showed a low viviparous germination rate of 5.2%. The yield capacity of ‘Shingil’ was 745kg/10a over two years based on a regional yield test. The amylose content of ‘Shingil’ is 23.4% with the grain showing opacity in most parts of the endosperm, which is caused by the round particle shape, unlike the polygonal shape of ordinary grains. Thus, ‘Shingil’ could be used as a rice flour source in various processing field and dry milling industries where milling costs could be saved (Registration No. 8019).