The spectrum of this study was research on the closed hydroponic cultivation of netted melons (Cucumis melo L.) using coir substrate, analyzing the impact of this cultivation method on melon yield, fruit quality, and the efficiency of water and nutrient usage. The experimental results showed that the average fruit weight of the melons grown in a closed system was 71.4 g higher than that of the open system, and the fruit width was on average 0.2 cm larger, showing a statistically significant difference. However, there was no difference in the average sugar content of the fruit flesh and height. Although there is no substantial commercial difference, it is conjectured that the change in the macronutrients ratio in the irrigation has played a role in the statistically significant increase in fruit weight, which is attributed to changes in the crops' nutrient uptake concentrations. This necessitates further research for a more comprehensive understanding. In terms of the productivity of irrigation required to produce the fruit, applying the closed system resulted in an increase of 7.6 kg/ton compared to the open system, saving 31.6% of water resources. Additionally, in terms of nutrients, cultivating in a closed system allowed for savings of approximately 59, 25, 55, 83, 76, and 87% of N, P, K, Ca, Mg, and S, respectively, throughout the entire cultivation period. As the drainage was reused, the ratios of NO3 - and Ca2+ increased up to a maximum of 9.6 and 9.1%, respectively, while the ratios of other ions gradually decreased. In summary, these results suggest that closed hydroponic cultivation can effectively optimize the use of water and fertilizer while maintaining excellent fruit quality in melon cultivation.
Ni–Cr–Al metal-foam-supported catalysts for steam methane reforming (SMR) are manufactured by applying a catalytic Ni/Al2O3 sol–gel coating to powder alloyed metallic foam. The structure, microstructure, mechanical stability, and hydrogen yield efficiency of the obtained catalysts are evaluated. The structural and microstructural characteristics show that the catalyst is well coated on the open-pore Ni–Cr–Al foam without cracks or spallation. The measured compressive yield strengths are 2–3 MPa at room temperature and 1.5–2.2 MPa at 750oC regardless of sample size. The specimens exhibit a weight loss of up to 9–10% at elevated temperature owing to the spallation of the Ni/Al2O3 catalyst. However, the metal-foam-supported catalyst appears to have higher mechanical stability than ceramic pellet catalysts. In SMR simulations tests, a methane conversion ratio of up to 96% is obtained with a high hydrogen yield efficiency of 82%.
We investigated the effect of glutathione supplementation on body weight gain, feed intake, velvet antler yield and economic analysis in elk bulls. A total 14, 2-year old male elks were divided into 2 groups with control or glutathione treatment. Elks were fed concentrate feed at the level of 1.5% relative to body weight (3.1 kg). and allowed to consumed hay as roughage ad libitum. Glutathione was supplemented at the level of 6 mg/kg. Average daily gains (ADG) for 2-years old elks were 234.1± 7 and 247.6±22 kg in control and glutathione fed groups, respectively. Treated group had higher ADG than control (p<0.05). Individual daily DM intakes were 5.34±0.70 and 5.64±0.71 kg in control and glutathione supplemented groups, respectively. Glutathione-fed group showed an additional intake of 298 g on an average. Production of velvet antlers for elk yearlings was 4,229±720 g and 4,653±960 g in control and glutathione supplemented groups respectively. Analysis of economics efficiency revealed 8% higher revenue index in glutathione supplemented groups. In conclusion, glutathione supplementation showed increase of DM intake and ADG in elk bulls, and could also increase velvet antler production.
This experiment was carried out to investigate the effect of pure mineral nitrogen fertilization on dry matter yield and to determine the amounts of advisable mineral nitrogen according to difference of annual precipitations in permanent grassland. The re
This experiment was carried out to determine the effect of pure mineral nitrogen fertilization on dry matter yield and the amounts of advisable mineral nitrogen on grassland according to its age at the "Federal Institue for Agriculture in the Alps" in Aus
This experiment was to study the effect of pure mineral nitrogen fertilizing on seasonal distribution of dry matter yield and the advisable mineral nitrogen amounts on grassland. The results were as follows: 1. With longer regrowth periods the absolute dr
This experiment was carried out to study the effect of pure mineral nitrogen fertilizing on dry matter yield of grassland and the advisable mineral nitrogen amounts in long duration under practical conditions at the "Federal Institute for Agriculture in t
Extensive research has been conducted on effects of drought stress on growth and development of soybean but information is rather restricted on the limited-irrigation system by way of precaution against a long-term drought condition in the future. The experiment for limited-irrigation was conducted in transparent vinyl shelter at Asian Vegetable Research and Development Center (AVRDC), Taiwan in 1997. Two soybean varieties, Hwangkeum and AGS292, improved in Korea and AVRDC, respectively were used for this experiment. The relationships between normalized transpiration rate (NTR) and fraction of transpirable soil water (FTSW) in both varieties were similar that the NTR was unchanged until FTSW dropped to about 0.5 or 0.6. At FTSW less than those values, NTR declined rapidly. Days required to harvest in both varieties were significantly prolonged at IR6 treatment compared to any other treatments. Daily mean transpiration rate was significantly higher at IR5 treatment, as averaged over varieties. Similarly, water use efficiency was also high at 1R5 treatment. In both varieties, seed yield was the greatest at the IR5 treatment, as compared to any other limited-irrigation treatments, due to the increased seed number and high transpirational water use efficiency. The indices of input water and seed yield for the different limited-irrigation treatments against control indicated that Hwangkeum produced 59.6% or 60.7% of seed yield using 36.1% or 44.9% of input water, as compared to control, by irrigation at only R5 or R6 stages, respectively. The AGS292 produced 56.1% of seed yield with 35.4% of input water of control, when irrigated at R5 stage. The results of this study have elucidated that the limited irrigation at R5 stage in soybean can be minimized yield loss with such small quantity of water under the environment of long-term drought stress and the expected shortage of agricultural water in the future.