• Journal of The Korean Society of Grassland and Forage Science
• /
• v.24 no.1
• /
• pp.53-60
• /
• 2004

Recently, there has been a growing tendency to use whole crop rice for feeds as there is an increased rice supply and a decrease in the demand for rice in Korea. Little information, however, is available about the management and utilization of whole crop rice for feeds. This study was conducted to decide the optimum harvest date through examining the plant height, dry matter(DM) yield and feed composition of whole crop rice harvested at different maturity. Field study was established early in May until October 7th on a rice field at Yupori, Sinbuk-yeup, Chunchon, Kangwon-Do. "Ilpum" mutant rice was sown at 52 kg/ha, and N, P and K were applied at 209, 113 and 81 kg/ha, respectively. The rice was harvested at six different mature stages for analysis; booting stage; 17 Aug., milk-ripe stage; 27 Aug., dough stage; 7 Sep., yellow ripe stage; 17 Sep., dead ripe stage; 27 Sep. and full ripe stage; 7 Oct. Plant height was 77 cm in booting stage (P<0.05) which was lower when compared to the other stages among which the heights did not differ with average range of 93∼97 cm. The highest dry matter yield was observed in yellow ripe stage (22.8 T/ha), which was followed by dead ripe stage (19.3 T/ha), full ripe stage (19.3 T/ha), and dough stage (15.1 T/ha). Crude protein (CP) and Neutral detergent fiber (NDF) concentrations consistently decreased with maturity. The highest concentrations of CP and NDF were obtained in booting stage with 9 and 73.6%, respectively (P<0.05), and lowest in full ripe stage with 5.8 and 64.6%, respectively (P<0.05). The concentration of total digestible nutrient (TDN) was highest in booting stage (59.7%); however no significant difference was found among other stages. The concentrations of Ca and P were not different among mature stages. According to these results, the yellow ripe period is appropriate to harvest the whole crop rice for forage considering dry matter yields, feed compositions and TDN concentrations.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.61 no.2
• /
• pp.104-112
• /
• 2016

A double-cropping system with soybean (Glycine max) following the cultivation of potato, garlic, and onion is widely adopted in the southern region of Korea. For this system, marginal dates for planting must be determined for profitable soybean yields, because the decision to plant soybean as a second crop is occasionally delayed by harvest of the first crop and weather conditions. In order to investigate the effect of planting date on soybean yield, three cultivars (early and late maturity) were planted on seven different dates from May 1 to July 30 in both paddy and upland fields across 2012 and 2013. Soybean yields were significantly different among the planting dates and the cultivars; however, the interaction between cultivar and planting date was not significant. Based on linear regression, the maximum yield of soybean was reached with a June 10 planting date, with a sharp decline in yield for crops planted after this date. The results of this study were consistent with those of a previous one that recommends early and mid-June as the optimum planting period. Regardless of soybean ecotype, a reduction in yield of greater than 20% occurred when soybean was planted after mid-July. Frost during soybean growth can reduce yields, and the late maturity cultivars planted on July 30 were damaged by frost before completing maturation and harvest; however, early maturity cultivars were safely harvested. For sufficient time to develop and reach profitable yields, the planting of soybean before mid-July is recommended.

• Korean Journal of Soil Science and Fertilizer
• /
• v.8 no.4
• /
• pp.199-217
• /
• 1975

For the establishment of efficient method of potassium topdressing on rice the optimum time and amount were investigated and discussed on the basis of available data from nutriophysiological studies, soil characteristics and fertilizer trials in fields. The followings were pointed out. 1. According to yield rice plants require more potassium around heading under water culture. 2. Potassium involves in harvest index, filled grain ratio, grain weight and number of spikelets per panicle. 3. Potassium is lost after heading in most fields in spite of highest requirement during this period. 4. The higher $K_2O/N$ ratio in straw at harvest is, the higher the yield. 5. Relatively low efficiency of potassium fertilizer under the field condition may be due to improper application method rather than natural supply from soil and irrigation water. 6. Appropriate topdressing time appears at in effective tillering stage for the prevention of nitrogen excess and at 15 to 20 days after transplanting, ear formation stage and 5 days after heading for the prevention of soil reduction damage. Two times of topdressing for clayey soil and three times for sandy soil seems reasonable in practice together with nitrogen topdressing, 7. The reasonable ratio basal to topdressing of potassium fertlizer seems to be 2/3 and $N/K_2O$ ratio of fertilization for ear formation stage appeared also as 2/3.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.22 no.2
• /
• pp.81-88
• /
• 2020

Pleurotus pulmonarius 8 cultivas, domestically bred, were cultivated and evaluated for cultural properties. The morphological properties of 8 cultivars were big diameter of pileus and short stipe. Stipe was eccentrically combined with pileus. The longest length of stipe was Yeoleumneutali 2ho(72.8mm) while shortest cultivar was Yeoleumneutali 1ho(33.8mm). The diameter of pileus ranged 45.8-62,3mm, Yaksan was the smallest one and Yeoleumneutali 2ho was largest cultivar. Yield was largest in Yeoleumneutali 2ho(80.7g) whereas smallest was in Yeoleumneutali 1ho(35.5g). The highest L value was in Yeoleumneutali 2ho and Hosan. Lightness was not even around pileus but thicker in rim area and thinner in center of pileus. Average period of pinheading and harvest were 4.6 and 8.0 days thus only 3-4 days after pinheadng were required for harvest.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.42 no.3
• /
• pp.176-182
• /
• 2022

The aim of this study was to investigate dry matter productivity and nitrate nitrogen content in the growth stages of barnyard millet (Echinochloa esculenta) cultivated for feed, which was treated with different nitrogen fertilization levels. An early variety of barnyard millet (cv. Shirohie) was used for the test, and the different treatments with nitrogen fertilizer were as follows: 50% (N-40 kg/ha, T1), 100% (N-80 kg/ha, reference amount, T2), 150% (N-120 kg/ha, T3), 200% (N- 160 kg/ha, T4), 250% (N-200 kg/ha, T5), and 300% (N-240 kg/ha, T6). Sowing was done on May 13, 2021 and plants were harvested for four stage; vegetative stage, elongation stage, heading stage, and milk stage. The length of the millet increased significantly as the amount of nitrogen fertilization increased during the harvest period (p<0.05), but the difference was insignificant during the milk stage (p>0.05). Moreover, barnyard millet dry matter yield increased significantly as the levels of nitrogen fertilization increased (p<0.05), but there was no significant difference in dry matter yield among nitrogen fertilization levels during the heading stage (p>0.05). Chlorophyll also was significantly higher in T5 (250%) at all harvesting times, whereas nitrate nitrogen content was highest at the vegetative stage, gradually decreased as growth progressed, and lowest at the milk stage. Finally, as the nitrogen fertilization levels increased, the nitrate nitrogen content was significantly higher in all treatment groups (p<0.05). Therefore, our results suggest that the most appropriate nitrogen fertilizer levels is between 150%-200%, considering the dry matter yield, feed ingredients and nitrate nitrogen content in barnyard millet for feed.

• Korean Journal of Environmental Agriculture
• /
• v.41 no.3
• /
• pp.153-157
• /
• 2022

BACKGROUND: The residue dissipation pattern of pesticides for agricultural products during the pre-harvest period after the final application is important to prevent the maximum residue limit (MRL) violations in domestic and export markets. The MRL violations of carbendazim are observed more often in chamnamul by pesticide residue management surveys by the Ministry of Food and Drug Safety. The residue level at the pre-harvest interval (PHI) and the residue dissipation constant from the critical good agricultural practice (cGAP) trials could be estimated to meet the MRL and pose a health risk to consumers. METHODS AND RESULTS: Chamnamuls were harvested at 0, 1, 3, 5, 7, 10, and 14 days after application of carbendazim in accordance with critical GAP. The residue analysis in chamnanul was performed by HPLC-DAD with the C₁₈ column. The limit of quantitation of carbendazim was 0.04 mg/kg, and the recoveries were 74.4 - 95.8% at the two spiked levels (LOQ and 10LOQ) of carbendazim. The dissipation rates in chamnamul were calculated from the residues at the sampling days by statistical method at a 95% confidence level. The biological half-lives of residual carbendazim in the field trials 1 and 2 were 4.9 and 4.4 days, respectively. CONCLUSION(S): In this dissipation study, the residue concentrations at the recommended PHI were higher than the established MRL in Korea. Therefore, the MRL is proposed based on the residue data sets from the trials conducted at the same cGAP and the dietary exposure assessment.

• Journal of Ginseng Research
• /
• v.27 no.3
• /
• pp.141-145
• /
• 2003

The multi-year production cycle for ginseng can be rapidly depreciated by inferior post-harvest activities. This research examines the character of high temperature drying regimes for North American ginseng root to assist management decision making. The objective is a very rapid drying regime, that will not result in physical or chemical damage to the root and that would not alter the actual dry root weight. Research is presented using drying temperatures of 55, 70 and 105 C. Temperatures above these rapidly cause substantive physical damage to the root samples and seriously compromise the dry root values determined. Temperatures below these behaved quite similar to actual dryer regimes (approximately 38 C). Laboratory results indicate that there are differences between the three temperature regimes tested. Careful usage of the 70 C regime, over a period of two to three days in a convection drying oven, has distinct merit.

• Journal of Biosystems Engineering
• /
• v.23 no.5
• /
• pp.473-480
• /
• 1998

This study was performed to analyze the variation of various physicochemical factors related to the freshness of apple and tomato during post-harvest period. The total soluble solids content, uronic acid content, cell surface roughness. density, rupture deformation and rupture force were measured for 39 days at 7-day intervals for apple and for 11 days at 2-day intervals for tomato. respectively. The cell surface roughness of apple increased with the elapsed time, while the rupture force decreased. In case of tomato, uronic acid content, density and rupture deformation increased with the elapsed time whereas the rupture force decreased. Both apple and tomato exhibited the significant correlations among those physicochemical factors.

• Journal of Plant Biology
• /
• v.22 no.3
• /
• pp.63-69
• /
• 1979

The plant growth and net production, the nitrogen uptake and recycling, the nitrogen mobility and allocation to each organ, and the nitrogen utility from the Italian rye grass field during the population development were analyzed in comparison with different clipping treatments. The maximum dry matter standing crop and nitrogen quantity of harvest increased significantly, however, the annual amounts of dry matter and nitrogen assimilation showed little variations with increasing clipping frequencies. Plants treated with frequent clippings allocated relatively more nitrogen to leaves and less to roots during the experimental period. The amount of recycling of nitrogen decreased considerably due to frequent clippings. The annual averages of nitrogen utility indices changed in inverse relation to the nitrogen availability; such as 63, 58, 44 and 35 for C, A, M and J plots, respectively.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.1 no.1
• /
• pp.9-16
• /
• 1972

Twenty kinds of minerel nutrient solution were prepared and supplied to the tomatoes planted in Norwegian quartz pots. These plants were cultured for nine weeks and several physiogical phenomena were observed during the growing period, and after harvest, the alkaloid contents were determined. The highest growth potential was in NS 3 group while the highest alkaloid content wasein KMg 18 group.