• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.5
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• pp.374-378
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• 2002

To evaluate growth habits, fresh pod yield potential, and possibility of early and late seeding, seeding dates were extended from March 21 to June 20 by PE mulching and non-mulching. Soil temperature, under 5cm from surface, above 15$^{\circ}C$ at 10 a.m. in early seeding reached about March 25 in mulching and April 5 to April 12 in non-mulching. Days to emergence and first flowering were accelerated owing to increasing temperature, as seeding was delayed. Days to emergence according to seeding dates reduced 21 to 8 day in mulching and 33 to 10 day in non-mulching. Days to flowering were ranged from 51 to 26 day in mulching and from 69 to 32 day in non-mulching and differences between mulching and non-mulching on each seeding date had 18 to 4 days. Early seedings till April 21 had 160-170 flowers per plant for 8 weeks, while late seedings from May 21 increased more speedily with 200 flower for 6 weeks. Harvesting of fresh peanut, at 80 days after first flowering, was possible from Aug. 1 to Oct. 7 (133-108 days to harvest) by mulching and from Aug. 19 to Oct. 12 (151 to 114 days) by non-mulching. Yields between mulching and non-mulching in early seeding until April 21 had more difference, but in late seeding after May 21 was higher and showed insignificance. Pod setting periods by early and late seeding were about 3 weeks equally. In late seeding pod setting were almost concentrated for front 15 days. In spite of difference of fresh pod weight between two seeding times, the distributions of average of seed weight showed nearly same tendency.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.93-97
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• 1977

The rate of damaged soybean seeds by pod borer averaged 7.4% with the range of 1.2%-21.3% and tended to be higher in the lines with hairy pods comparing to those with hairless pods. The susceptibility of pod borer was negatively correlated with the pod setting date. while was not significantly affected by the weather conditions during the pod setting period.

• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.397-400
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• 2006

The objectives of this experiment was to evaluate the effect of seeding and transplanting date on yield and quality of rapeseed experiment were conducted in the research field of Chungcheongnam Do(Taejun) Agricultural Research and Extension Services with Yudal, one of the rapeseed cultivar of different growth characteristics among the six treatments were examined and recorded. Results showed that yield components such as plant height, length of ear and pod, number of branches and pods and percentage of pod setting and seed set were highest at the plot with direct seeding in Sep. 10. In this treatment yield of seed, 1,000 grains weight and weight of $1{\ell}$ were highest. On the basis of vegetative and yield parameter of direct seeding in Sep. 10 was the best sowing date of rapeseed crop in Chungcheongnam Do region of Korea. Experiments were conducted in the research field of Chungcheongnam Do(Taejun) Agricultural Research and Extension Services with Yudal variety, which showed different growth characteristics. Yield components such as plant height, length of ear and pod, number of branches and pods and percentage of pod setting and seed set were highest at the plot with direct seeding in Sep. 10. Yield of seed, 1,000 grains weight and weight of $1{\ell}$ were highest at the direct seeding in Sep. 10. Judging from the results reported above, seemed to be direct seeding in Sep. 10.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.3
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• pp.171-175
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• 2000

This study was carried out to obtain the basic informations on the flowering habit, pollination patterns and seed setting in Astragalus membranaceus. The first flowering appeared at the 20-22 node on main stem and there is the indeterminate inflorescence that the flowering progress developed toward the tip of the main stem and also toward the tips of branches. According to the flowering time, the number of peduncles were increased in early of Aug. Then, the number of bearing pods and that of seed setting were increased at that time. The length of peduncles with small flower was 6.6-7.3cm, and the number of small flowers were 13-17 per peduncles. The percentage of seed setting was 30-45% per peduncles and seeds were 4.8-5.3 per pod in peduncles. On 30 days after pollination, the pod was developed with the length about 3.8cm and the width about 8mm and the seeds were 7.3per pod. According to pollination treatment, wrapping sotted no seeds and the artificial pollination sotted seeds . about 5% in late of jul. to late of Aug. but increased about 13% of seed set after early of Sep. in A. membranaceus.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.326-326
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• 2017

Climate warming is the issue on the global scale. Soybean can be seriously damaged when high temperature occurs during a reproductive stage such as the flowering and pod-setting period according to the Representative Concentration Pathway (RCP) (2021~2100) 8.5 scenarios. The weather in 2016 was very different from other years (average for 30 years from 1980 to 2010) ; the highest temperature was $33.7^{\circ}C$ which was higher $3.29^{\circ}C$ than average temperature from last 30 years and average rainfall was 26.5 mm, lower 140.9 mm than average rainfalls from other years. Especially, the highest temperature during soybean flow-ering and pod setting stage was $26.8^{\circ}C$ which was higher $0.1^{\circ}C$ and rainfall was 172.2 mm, higher 47.8 mm than other years from the first to the 20th in the October at soybean seed elongation stage. Soybean leaves were turned upside down by the drought stress during the flowering and pod-setting stage. The numbe-r of pods and seeds per unit area decreased 11.0% and 30.3% compared with the previous year, respectively. The ripening period was prolonged by 21 days because of high temperature and soil moisture contents due to the continual rainmade increase of the seed weight up to 15.6% and the yield decreased 7.1% compared to the previous year.

• Korean journal of applied entomology
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• v.18 no.2 s.39
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• pp.101-106
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• 1979

Present studies were carried out to get a basic information for biological control of soybean rod borer, Grapholitha glycinivorella Matsumura, causing main injury in soybean cultivation in Korea. 1474 native strains were cultivated in field to evaluate the pod borer damage. Pubescence density and color, maturity group, seed coat color, aphid and general leaf damage and seed damage by pod borer were investigated, and determined among their relationships. As another basic study for ecological control of insect, 6 leading varieties were planted on different planting date with 3 levels of plant spacing, on which pod borer damage and some related agronomic characters were studied. The results obtained one summarized as follows: Average injury of soybean pod borer was $5.2\%$ ranging $0-38\%$ in 1474 strains planted on 20 May. Non-significant correlations were found between pod borer damage and pubescence density and color, while pod borer damage closely related with maturity groupand aphid damage at $5\%$ level ofttests. Most severe damage was found in green seed coast color and maturity group V. Late and sparse plantings tend to have more damages to the pod borer than those of early and dense plantings. Pod setting date and period of pod maturing seemed related with pod borer damage. Bongeui and Chungbuk-baik cultivars were resistance to soybean pod borer, while Clark and Kumkang-daerip were susceptible in field tests.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.4
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• pp.269-276
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• 2019

A semi-greenhouse experiment with field grown soybean (Glycine max L. cv Deawon, Uram, Jinpong, Soyon, Pungsangnamul, and Haewon) was performed in 2018. The experiment was aimed to investigate individual impacts of drought stress on soybean characteristic and seed yield. The three treatments were used in non-water stress (Control) during the soybean growth season, vegetative stage stress (VS), and flowering period stress (FS). Leaf number, LAI, leaf nitrogen concentration, and leaf biomass were decreased by drought at R4. In our study, the number of pods was 33.6% and 40.5% lower, respectively, in control than in VS and FS. In 100 seed weight, was 16.1% and 10.1% lower, respectively, in control than in VS and FS at R8. As a result, seed yield was 39.8% and 45.1% lower, respectively, in control than in VS and FS. Depending on the drought period, Daewon and Haewon showed a large decrease in yield, while Soyon did not change. The results of this study showed that flower and beginning pod setting stage responded more sensitively to the drought period than vegetative stage. Overall, these results demonstrate soybean seed yield formation more sensitive the during the flowing and beginning pod setting stage. We conclude that adequate water supply for pod setting stage, guaranteeing a high seed yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.4
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• pp.251-256
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• 2000

Astragalus membranaceus has flowers that are similar to that of the legume family, but shows poor bearing when self-pollination is induced. Thus, this study was carried out observing the ripening procedure of pistils and stamens and development stages of pollen in the context of the birth and growth of the flower. As to the bearing of the flower of A. membranaceus, few pod setting and 13% pod setting were observed when self-pollination is induced by paper-bag covering or artificial pollination treated respectively. The result indicates that A. membranaceus is a cross-pollination plant. A pistil grew faster than a stamen until just before blooming. The flower size was about 17.0mm$\times$4.0mm. Pistils and stamens had the same length after flowering. Pollen mother cells passed through meiosis and mitosis when its length reached around 3.5mm, thus creating the tetrade when 4 mm long. Pollen attained full growth when the bud was about 10mm long. An anther was found to tend to dehisce when the length of a bud reached around 12.0mm. As to the shape of pollen, about 70 % were normal. 1% and 30 % were small or empty pollen respectively. The result indicates that pollen of A. membranaceus attains full growth just before anther dehiscence which occurs before blooming while pistils grow faster than stamens until before flowering.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.3
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• pp.246-251
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• 1989

A medicinal legume crop, Cassia tora L., was grown with four different seeding dates in 1986 field condition to find the flowering and pod setting characteristics. Initial flowering date and flowering duration were almost same between plants sown from April 20 to May 30, but those of plants seeded at June 20 were significantly delayed and shortened. Last flowering date, however, was not different between plants sown from April 20 to June 20. C. tora plants showed indeterminate flowering habit, and bloomed vigorously from fourth date after initial flowering. Numbers of flowers, ovules and pods per plant were decreased along with delaying seeding date, and ovule to flower ratio and pod to flower ratio were greatly decreased in June 20 seeding plot. Flowers bloomed on second week from initial flowering showed the highest number of ovules and pods, and flowers bloomed after early September did not develop to matured pods. Maximum values of pod length, number of seeds per pod and 1000-grain weight were obtained from flowers bloomed on second week from initial flowering of plants sown from April 20 to May 30, and first week in June 20 seeding plot.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.467-472
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• 2009

This study was conducted to break down the self-incompatibility of Astragalus membranaceus Bunge by old-flower pollination, NaCl and $CO_2$ treatment. The old-flower pollination in green house produced fertilization during the 1st and 2nd day after flowering from early September to early October, but almost no fertilization in late August. The most successful pollination occurred in late September at the 1st day after flowering when pod setting was 33.3% and that of seed set was about 86.2%. The old-flower pollination in field showed pod setting for the control group from late August to early October, but no seed set except the days of mid-September and late September. The most successful pollination occurred in late September during the 2nd day of flowering when the percentage of pod setting was 39% and that of seed set was 94.9%. The wrapping in field set pods from late August to early October, but did not set seeds except in mid and end of September. The percentage of pods was 39% and percentage of seeds was 94.9% about flowering after first day in end of September. by field culture. The best result from NaCl treatment was achieved when 1% NaCl treatment in green house produced 21.3% of pod setting in early October and 66.7% of seed set in late September. In field, NaCl 5% treatment produced best result with 7.3% of pod setting and 90.9% of seed set in mid-September. No differences were observed between the $CO_2$ 700ppm treatment and the control group.