• Journal of Bio-Environment Control
• /
• v.31 no.3
• /
• pp.194-203
• /
• 2022

Cultivation of tomatoes in Korea grown in soil covers 89% of the total area for tomato cultivation. Tomatoes grown in soil often encounter various environment stresses including not only salt stress and soil-borne diseases but also cold stress in the winter season. This study was conducted to comparatively analyze the performance of rootstocks with cold stress by measuring the growth, yield, and photosynthetic efficiency in tomatoes grown in soil. The rootstocks were used 'Powerguard', 'IT173773', and '20LM' for the domestic rootstock cultivars and 'B-blocking' for a control cultivar. The tomato cultivar 'Red250' was used as the scion and the non-grafted tomatoes. Stem diameter, flowering position, leaf length, and leaf width were investigated for the growth parameters. The stem diameter of the non-grafted tomatoes decreased by 15% compared to the grafted tomatoes at 80 days after transplanting when exposed to low temperatures of 9-14℃ for 14 days. The leaf length and width of the non-grafted tomatoes were the lowest with 42.4 cm and 41.8 cm at 80 days after transplanting. The total yield per plant was the highest in tomato plants grafted on 'Powerguard' with 1,615 g and lowest in non-grafted tomatoes with 1,299 g. As the result of measuring the chlorophyll fluorescence parameters, PI_ABS and DI₀/RC, which mean the performance index and dissipated energy flux, 'Powerguard' was the highest with 3.73 in PI_ABS and the lowest with 0.34 in DI₀/RC, whereas non-grafted tomatoes was the lowest with 2.62 in PI_ABS and the highest with 0.41 in DI₀/RC at 80 days after transplanting. The stem diameter has positive correlation with PI_ABS, while it has negative correlation with DI₀/RC. The results indicate that can be analyzed by chlorophyll fluorescence parameters can be used for analyzing the differences in the growth of tomato plants grafted on different rootstocks when exposed to cold stress.

• Journal of Bio-Environment Control
• /
• v.32 no.1
• /
• pp.40-47
• /
• 2023

There are many different types of cultivation in tomatoes for year-round production. One of them, semi-forcing cultivation is characterized by growing seedlings in winter season. If grafted seedlings are used in winter season that energy cost can be reduced, because they have tolerance to cold stress. This study was conducted to analyze the rootstock performance by measuring the growth, yield, and leaf-macronutrient content of cherry tomatoes grown in semi-forcing hydroponics. Three domestic rootstocks 'HSF4', '21LM', '21A701', and a control cultivar 'B-blocking' were grafted onto jujube-shaped cherry tomato (Lycopersicon esculentum L.) commercial cultivar 'Nonari'. The total yield per plant with grafted cherry tomato '21A701' was 3,387g, which was 11%, 22% and 24% higher than the yield with 'B-blocking', non-grafted one and 'HSF4'. The stem diameter of '21A701' was thick with 8.26mm, whereas non-grafted one was thin with 7.23mm at 160 days after transplanting. The flowering position of '21LM' was 34% and 47% higher than the flowering position of 'B-blocking' and non-grafted one at 153 days after transplanting. The NO₃-N concentration in petiole sap of '21LM' was the highest with 1,746mg·L^-1 and non-grafted one and 'HSF4' were the lowest with 1,252mg·L^-1 and 1,245mg·L^-1 at 167 days after transplanting. The results indicated that rootstock/scion combinations in cherry tomatoes can affect the plant growth, yield, and the concentration of different NO₃-N in leaves at the late growth stage. Both '21A701' and '21LM' have vigorous root system, which influence the growth and yield increased.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.67 no.1
• /
• pp.9-16
• /
• 2022

Rice is one of the most important staple foods in Wnju, Jeonbuk, South Korea. However, rice consumption has dramatically decreased as eating habits have diversified owing to rapid economic growth. Recently, floury endosperm rice varieties have been developed to invigorate the rice processing industry, because dry-milled rice flour is economically and environmentally suitable for massive rice flour distribution. The National Institute of Crop Science has developed 'AromaT', an early-maturing black rice with floury-endosperm, suitable for tea and dry milling. 'AromaT' was derived from a cross between 'Suweon542' as the floury endosperm source and 'Heugjinju' as the black and aromatic source. In this study, 'AromaT' and its parents, 'Suweon542' and 'Heugjinju', were analyzed for agronomic traits, anthocyanin content, and their major physicochemical properties by different planting date. The field experiment was conducted in Wanju, Jeollabuk-do Province, South Korea, in 2019. The transplanting dates were May 30 (ordinary season), June 25 (double-cropping season), and July 10 (late season). The yield performance of brown rice 'AromaT' was 330 kg/10 a in the double-cropping cultivation method and was the highest among the transplanting dates. The floury endosperm of 'AromaT' was derived from 'Suweon542' containing 'flo7', located on chromosome 5 and known to control floury endosperm. With the late planting date, the anthocyanin content of 'AromaT' was 570.5 mg/100 g, much higher than that of 'Heugjinju' (376.3 mg/100 mg). The brown rice of 'AromaT' also exhibited the pop-corn-flavoring 2-acetyl-1-pyrroline, exclusively detected in aroma rice varieties. The average particle sizes of 'AromaT' and 'Suweon542' were 67.12 ㎛ and 70.9 ㎛, respectively, lower than that of 'Heugjinju' (95.5 ㎛) with a black transparent endosperm. The average damaged starch content of 'AromaT' was 8.1%, lower than that of 'Heugjinju' (10.05%) and Suweon542 (9.5%). As a result, 'AromaT' with high anthocyanin content, fine particle size, and low damaged starch content is expected to provide a new rice material in various processing fields.

• Journal of Radiation Protection and Research
• /
• v.22 no.3
• /
• pp.171-181
• /
• 1997

A mixed solution of $^{54}Mn$, $^{60}Co$, $^{85}Sr$ and $^{137}Cs$ was applied to the soil of culture boxes in a greenhouse 2 days before transplanting red pepper and at 3 different times during its growth for investigating transfer factors ($m^2/kg-dry$) for its green and red fruits. Transfer factors varied with radionuclide, application time and harvest time by factors of about $20{\sim}100$. They decreased mostly in the order of $^{85}Sr>^{54}Min>^{60}Co>^{137}Cs$ while $^{54}Mn$ and $^{60}Co$ was higher than $^{85}Sr$ when time lapse between application and harvest was short. Transfer factors of $^{85}Sr$ and $^{137}Cs$ at the last application were lower than those at the previous one by factors of $3{\sim}20$ depending on harvest time. Variations in $^{54}Mn$ and $^{60}Co$ transfer factors with application time after transplanting were comparatively low. Transfer factors of $^{54}Mn$, $^{60}Co$ and $^{85}Sr$ mixed with topsoil before transplanting were up to $3{\sim}9$ times higher than those for the application onto soil surface 2 days after transplanting while there was no difference in $^{137}Cs$. The present results can be referred to in estimating root-uptake concentrations of the radionuclides in red pepper fruit and taking proper measures for its harvest and consumption at the event of an accidental release during the growing season of red pepper.

• Journal of Bio-Environment Control
• /
• v.22 no.2
• /
• pp.87-90
• /
• 2013

The average annual and winter ambient air temperatures in Korea have risen by $0.7^{\circ}C$ and $1.4^{\circ}C$, respectively, during the last 30 years. Due to climate change, the occurrence of abnormal weather conditions has become more frequent, causing damage to vegetable crops grown in Korea. Hot pepper, chinese cabbage and radish, the three most popular vegetables in Korea, are produced more in the field than in the greenhouse. It has been a trend that the time for field transplanting of seedlings is getting earlier and earlier as the spring temperatures keep rising. Seedlings transplanted too early in the spring take a longer time to resume the normal growth, because they are exposed to suboptimal temperature conditions. This experiment was carried out to figure out the change of cellular tissue of chinese cabbage under the condition of low temperature to provide the information regarding the coming climatic change, on the performance of 'Chunkwang' chinese cabbage during the spring growing season. In our study, plant height, number of leaf, chlorophyll and leaf area was lower at the open field cultivation than heating house treatment after transplanting 50 days. Especially in fresh weight, compared with heating treatment, open field and not heated treatment were notably low with the 1/3 level. Of damage symptoms due to low temperature cabbage leaves about 10 sheets when $-3.0^{\circ}C$ conditions in chinese cabbage was a little bit of water soaking symptoms on the leaves. $-7.4^{\circ}C$ under increasingly severe water soaking symptoms of leaf turns yellow was dry. Microscopy results showed symptoms of $-3.0^{\circ}C$ when the mesophyll cell of palisade tissue and spongy tissue collapse, $-7.4^{\circ}C$ palisade tissue and spongy tissue was completely collapsed. The result of this study suggests that the growers should be cautioned not to transplant their chinese cabbage seedlings too early into the field, and should be re-transplanting or transplanting other plants if chinese cabbage are exposed to suboptimal temperature conditions ($-3.0^{\circ}C$ or $-7.4^{\circ}C$).

• Korean Journal of Weed Science
• /
• v.3 no.2
• /
• pp.166-173
• /
• 1983

To investigate the varietal differences of weed competitive functions under the three different seasons of transplanting, rice cultivars Milyang 23 and Sadominori were used with seven weeding methods, namely, weedy check, weed-free, once weeding at 3, 6, 9, 12 weeks after transplanting, and two times weeding at 3 and 9 weeks after transplanting, respectively. As a result, weeding stages and times for the proper weeding efficacies and reasonable rice productivities by respective weed group and total weed flora were estimated. Also, the constructive characteristics for yield formations under the different competitive conditions as affected by various cropping patterns were discussed.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.55 no.1
• /
• pp.24-30
• /
• 2010

Comprehensive studies on seedling production and transplanting cultivation of waxy corn are necessary to fulfill the comsumer's preference for the high quality whole ear waxy corn and its year-round supply for higher price, and to escape marketing in a short period at harvest season. Two waxy corn hybrids (cv. Chalok# 1 and Chalok# 4) were used to study the effects of seeding date, nursery days and plug cell size on growth and yield of waxy corn, and to clarify the reliable transplanting date at the Experimental Field of the National Institute of Crop Science in 2007. The number of days from seeding to silking was increased as nursery days were extended, but the number of days from transplanting to silking was shortened comparing to the direct seeding. Number of days from seeding to silking was shorter by 9~12 days for Chalok# 1 than for Chalok# 4, while the number of days from seeding to silking was shorter by 12~15 days in the second cropping than in the first cropping. Culm length of transplanted waxy corns was decreased as the nursery days were extended. Culm length of seeded Chaok# 1 and Chaok# 4 were decreased by 17% and 24%, respectively, in the second cropping compared to those in the first cropping. Ear length was somewhat decreased as the nursery days were extended. Chalok# 1 in the second cropping the degree of decrease was much higher in second cropping than in first cropping of Chalok# 1. Comparing to the first cropping, number of marketable ears per 10a of Chalok# 1 decreased as high as 64%, while that of seeded Chalok# 4 decreased mere 12% in the second cropping.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.3
• /
• pp.349-355
• /
• 2010

This experiment was conducted to establish the optimum nitrogen application level for oriental melon at Seong-ju Fruit Vegetable Experiment Station with a fertigation system. Four different levels of nitrogen fertigation were applied to oriental melon and growth of the plant was analyzed. Plant samples were collected 8 times and were analyzed by the standard methods. The first fertigation was applied at 10 days after transplanting for the oriental melon based on the growth rates of the plants. For oriental melon, 10 day interval fertigation and 8 time split application of fertilizer could be recommended. The amounts of N, P, and K fertilizer recommended by soil testing was 249-408-315 (kg $ha^{-1}$). Treatment levels were 0, 0.5, 1.0, and 1.5 times of soil testing nitrogen with P and K level fixed. The total nitrogen (T-N) content in dried leaf showed a tendency to increase until 30 days after transplanting, then decreased. T-N content increased with increasing nitrogen fertigation rates. T-N content in dried fruit decreased slightly during the whole growing season. Fresh weight and nitrogen uptake were increased with increasing nitrogen fertigation rates. Total yield and marketable yield, 44,550 kg $ha^{-1}$ and 42,880 kg $ha^{-1}$, were maximized at 0.5 times of soil test nitrogen. Ratio of marketable fruit, 95%, was the highest at 0.5 times of soil test nitrogen. The optimum level of nitrogen for fertigation system was 0.5 times soil test nitrogen judging from total yield, commodity yield and commodity fruit.

• Korean journal of applied entomology
• /
• v.36 no.1
• /
• pp.55-66
• /
• 1997

This study was conducted to analyze arthropod community patterns in small rice fields associated with different planting methods (water seeding, drill seeding, and hansplanting) in Suwon and Icheon in 1994. Total 15 orders and 45 families of arthropods were collected. The arthropod community was analyzed using guild categories. The arthropods were found in the order of 'natural enemy>pest(phytophage)>non-pest' in their densities in all sites. The pest (phytophage) species were mainly Homoptera and dominated by Delphacidae (Nilaparvata lugens Stsl, Sogatella fircifera Horvath and Laodelphax striatellus Fallen) and Cicadelidae (Nephotettir cincticeps Uhler). They constituted >80% of pest abundance. Differences in pest abundance were not found among rice fields associated with different planting methods. Spiders were the most dominant group in the natural enemy and constituted >90% of natural enemy abundance. Hunting spiders constituted >SO% of spider abundance and were dominated by Pirata subpiraticus Bos. et Str. (Lycosidae). Pacliygnatha clerki Sundevall (Tetragnathidae) was a dominant species in webbing spiders. No differences were found in species richness and diversity in spider community among rice fields associated with different planting methods. The nonpest species were mainly Diptera and occurred abundantly in early growing season and decreased drastically as rice development proceeded. The non-pest abundance was higher in direct seeding sites than in transplanting site, and especially abundant in a drill seeding site.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.32 no.4
• /
• pp.379-385
• /
• 1987

A field experiment was conducted to find out the effects of liming (soil pH) and sources of N on the chemical constituents of soil and leaf lamina of burley tobacco. Treatments consisted of liming (nonliming, liming to soil pH 5.5 and 6.5) as the main plot and N sources［compound fertilizer of containing 3.9% $NH_4-N$ and 6.1% $NH_2-N,\;NaNO_3,\;(NH_2)_2CO\;and\;(NH_4)_2SO_4$］as the sub-plot. The soil pH was high in $NaNO_2$ plot, while low in $(NH_4)_2SO_4$. But the differences of Ca concentration in top soil among N sources were not detected. The $NO_3-N$ concentration in top soil was high in high limed and $NaNO_3$ plot. The $NO_3-N$ content of leaf (lamina) at 75 days after transplanting was high in $NaNO_3$ plot and CaO con-tent of leaf at 45 days after transplanting was high in high limed plot. But neither liming nor N source had effect on the contents of total nitrogen, $P_2-O_{5}\;and\;K_2O$ of leaf during growing season. There was no significant differences in total alkaloid and total nitrogen contents of cured leaf (lamina) to liming and N source. But when the source of N was $NaNO_3$, the content of total alkaloid was increased by adding lime. When the source of N was $(NH_4$)_2SO_4$, the content of $K_2O$ in cured leaf was high while CaO was low. But neither liming nor N source had effect on the contents of $P_2-O_{5}$ and MgO in cured leaf.