• Weed & Turfgrass Science
• /
• 제3권2호
• /
• pp.130-136
• /
• 2014

Tall fescue is commonly well-adapted for low maintain area because of its wear resistance, deep root system, and drought tolerances. Deep and infrequent irrigation refers to applying large amounts of irrigation, 1.3 to 2.5 cm or more, in a single irrigation event. Light and frequent irrigation is commonly used with small amounts of water, 0.3 to 0.6 cm, every day or every other day. N use for turfgrass management is often unnoticed for water management. The objective of this field study was to evaluate the effects of irrigation frequency and N rates for tall fescue growth. The three irrigation treatments were no irrigation (precipitation only), 0.5 cm applied every other day, and 1.8 cm applied once a week at one irrigation event. The nitrogen (N) treatments were the low, medium, and high N rate treatments. The low, medium, and high N treatments were applied over 2, 4, and 6 applications, respectively. If high main maintenance of tall fescue is not important and water source is limited, irrigation is not necessary and, the $9.8gNm^{-2}yr^{-1}$ of two applications can be recommended for tall fescue under the weather condition of the study.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2008년도 학술발표회 논문집
• /
• pp.827-831
• /
• 2008

In this study, the effects of reclaimed wastewater irrigation on the concentration of heavy metals such as lead, zinc, cadmium, and copper in soil and vegetables were investigated by monitoring an experimental area irrigated with reclaimed wastewater. Three treatments and three replications on $10{\times}2$-m plots were installed and heavy metal concentrations in soil and vegetables were monitored from 2005 to 2007. The treatments applied in this study were groundwater irrigation (control treatment), wastewater irrigation, and irrigation with filtered reclaimed wastewater treated with ultraviolet light. The monitored results showed that the concentrations of Cu, Cd, and Pb in soil during the experimental period were lower than initial soil levels before irrigation, whereas Zn increased in all treatment plots. However, the ranges of Zn, Cu, Cd and Pb in soil were below the soil pollution standards in the Republic of Korea. Heavy metal concentrations in vegetables showed insignificant variations for all treatments.

• 한국농공학회지
• /
• 제17권3호
• /
• pp.3795-3814
• /
• 1975

The purpoes of this thesis is to study the effect of the variation of the beginning date of the suspension of irrigation and the length of intermittent suspension period of irrigation in the paddy field on the growth and yield of rice, so as the provide a critical limit of saving irrigation water and an irrigation method to prevent drough damage in rice cultivation. In this experiment, the rice variety adopted was NONGRIM No.29. There were seven main test plot, each test plot having a different beginning date of the suspension of irrigation. A main test plot was susdivided into five small test plots, each having a different length of the suspension period of irrigation. The results obtained in this experiment are summarized as follows: 1. The number of tillers is controlled by the treatment of the suspension of irrigation, its beginning date being early of late. The reductive effects of beginning dates of suspension upon the number of tillers. investigated on July 30, are about 84% for the treatment suspended on July 8, 87% on July 12, and 92% on July 19, respectively, in comparison with the standard plot. However. the suspenion treatments after the foregoing dates does not affect the control of their numbers. On the other hand, the lengths of intermittent suspension periods influence highly on the number of tillers to be restrained considerably, the decrease ratio ranging from 91% to 80% Both treatments on dates and periods are so intermingled that the restraining effects of suspension periods become greater as the dates of its beginning are earlier. 2. The elongation of plant hieghts also restrained considerably by the longer periods and earlier dates of suspension treatments of irrigation. Especially, the effects of the lengths of suspension periods become more serious. 3. Heading dates are delayed by two to five days through the suspension treatments of irrigation. However, the heading stage ends almost on the same day without relation to the differences between the irrigation suspension treatments. In the test plot where the suspension date of irrigation comes after the young panicle forming stage, the heading stage ends one or two days later than in the standard test plot. 4. Both culm lengths and panicle lengths show significant differences in their values, i.e., their lengths are shorter, as the begining dates of irrigation suspension are earlier and the suspension periods are longer. 5. The earlier the beginning date and the longer the period of irrigation suspension, the less is the number of panicles per hill in comparison with the standard plot. 6. The earlier the beginning date and the longer the period of irrigation suspension, the higher is the significant difference in the number of kernels per panicle in comparison with that in the standard test plot, i.e., the less is the number of kernels per panicle. 7. The earlier the beginning date and the longer the period of irrigation suspension, the lighter are the weights of rough rice and straws per hill in comparison with those in the standard plot.

• 생물환경조절학회지
• /
• 제27권2호
• /
• pp.103-110
• /
• 2018

본 연구는 하절기 '매향' 딸기 자묘의 삽목 번식에 적절한 관수 방법을 구명하기 위해 수행되었다. 딸기 자묘의 삽수는 24구 딸기 전용 포트(24구, $60{\times}34{\times}10cm$)에 상업용 혼합 상토(Tosilee)를 이용하여 삽목하고, 반 밀폐형 소형비닐터널에 위치시켰다. 각각의 반 밀폐형 소형터널의 처리는 다음과 같이 처리했다; 대조구(무처리), 두상관수(하루 두 번), 매트관수(하루 두 번), 그리고 안개관수(8:00시부터 18:00시까지 30분 온/오프 설정). 딸기 자묘는 반 밀폐형 소형터널 내에서 8일 동안 발근을 하였고, 그 이후 플라스틱 필름을 제거 하였다. 삽목 후 61일째에 초장, 근장, 1차 근수, 엽병장, 엽장, 엽폭, 크라운 직경, 엽록소 값, 엽면적, 지상부와 지하부의 생체중 및 건물중을 측정하였다. 터널 내의 하루 평균 상대습도는 각각 안개관수, 두상관수, 매트관수, 대조구 순으로 72.5, 56.3, 45.8, 그리고 29%를 나타냈다. 그러나 공기온도는 모든 처리에서 유사하였다. 딸기 자묘의 4일째와 8일째 발근율은 두상관수와 안개관수 처리에서 유의적으로 높았다. 초장, 엽병장, 크라운 직경, 엽면적은 두상관수와 안개관수 처리에서 높은 값을 나타냈다. 게다가 지상부의 생체중 및 건물중은 다른 처리에 비해 두상관수와 안개관수 처리에서 무거웠다. 지하부의 건물중은 안개관수 처리에서 유의적으로 무거웠다. 하지만 근장, 1차 근수, 엽록소 값, 지하부의 생체중은 모든 처리구에서 유의적인 차이를 나타내지 않았다. 결과적으로, '매향' 딸기의 삽목 번식 시 생육과 발근율은 두상관수와 안개관수 처리에서 가장 효과적인 것으로 나타났다.

• 한국농공학회지
• /
• 제8권2호
• /
• pp.1193-1199
• /
• 1966

More stable and higher yields in rice paddy depend mainly upon an adequately balanced supply of water for higher yield. Rice paddy is supplied naturally by rainfall but inevitably requires artificial supplenental irrigation for higher yields. Even though it may be true that the water requirement of rice plants is generally higher than those of other crops, the submerged condition is not necessarily required for rice. The moisture requirements of rice vary according to its growing stages and it is possible to increse the irrigation efficiency by means of lessening the loss due to percolation and evapolation in the field. This experiment was conducted on the effect of the various amount of water supply and different irrigation periods for yield and yield components, and was carried out to find out the most suitable irrigation method and to increase the irrigation efficiency for higher yields in rice paddy. Randomized block design with 3 replications was employed where the 3 levels of the amount of irrigation water; (120% moisture contents), unirrigated (90~100%) and more un irrigated candition (80~90% moisture content), and levels of the various irrigation periods; usual, initial, intermediate and final periods, being treated. The results obtained in this experiment are as follows: 1. As for the physical and chemical and soil properfies, and other characteristics, there are no differences among the treatments enough to be effective for the growth of rice plants. 2. Culm length was measured after harvest as shown in table 2. 3. Difference of the amount of irrigation water did not change the culm length and ear length, however it also indicated more apparent increase in final treatment plots thatn that of usual. 3. No difference in the number of ears and number of ears pers per hill was founded treatments both in the difference of water supply and in the various irrigation periods. 4. There is no difference in the maturing rate and 1000 grains weight. 5. The number of panicles and grains and more increased in 80~100% moisture contents soil than those of 120%. and it shows in un irrigated plots, more irrigated plots and control plots in turn. Other wise according to the period\ulcorner of irrigation the trend is appeared in turn initial, usual, final and intermediate treatments.6. Yield as shown in table 7. 8 was more increased in unirrigated plots(90~IOO% moisture content) than the control plots (120% moisture content) by up to 8.2% and also 3. 2% in more unirrigated plots than that of control by periods is shown: usual plots final, initial, inter mediate treatment plots in turn. 7. The above resutts lead to the conclusion that no remarkable, differences in yields and soil properties are made by the unirrigation. However, it is apparent that this treatment has .some advantages in the points that one could spare the amount of water supply for irrigation with more increase in yield. In addition, a higher temperature and a brisk oxygen supply would be possible throug h this treatments. Accordingly, these treatment would be a more reasonable and economical cultivation method of rice for the better harvest.

• 한국작물학회지
• /
• 제44권4호
• /
• pp.330-338
• /
• 1999

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.

• 한국농공학회논문집
• /
• 제47권4호
• /
• pp.75-85
• /
• 2005

A study was performed to examine the effects of reclaimed-water irrigation on microorganism con-centration in ponded-water of paddy rice plots. Several treatments were used and each one was triplicated to evaluate the change of indicator microorganisms (total coliforms (TC), fecal coliforms FC), and E. coli) concentrations in 2003 and 2004 growing seasons. Their concentrations increased significantly right after irrigation, but decreased about $45\%$ in 24 hours. It implies that agricultural activities such as plowing and fertilizing should be practiced one or two days after irrigation considering health-risks. Treatments with UV-disinfected water irrigation demonstrated significantly lower concentrations than others including control plots where natural surface water was irrigated. The monitoring results from actual paddy rice fields and experimental paddy plots showed that concentrations of indicator microorganisms ranged from $10^2\;to\;10^5$ MPN/100mL. A comprehensive assessment of existing agricultural practices and a thorough monitoring in the field as well as treatment-plots are recommended to make more realistic national guidelines more applicable. UV-disinfected water irrigation reduced microorganism concentrations in paddy fields down to below the concentration of conventional paddy rice culture, and is thought to be an effective and feasible measure fur agricultural reuse of secondary effluent.

• 한국작물학회지
• /
• 제67권2호
• /
• pp.121-130
• /
• 2022

본 연구는 봄 감자 재배 시 괴경 형성기와 괴경 비대기에 최적 수분함량을 구명하고 관비 재배 시 적합한 추비 기준을 마련하고자 수행 하였다. 1. 감자의 최적 수분함량을 구명하기 위한 괴경 형성기와 괴경 비대기에 관수처리 결과 관수처리 전후 지상부의 생육을 비교한 상대생장률과 대조구(무관수, 자연강우 의존) 대비 상대 생장률 모두에서 -10 kPa 및 -20 kPa 처리구에서 우수한 경향을 보였다. 2. 관수처리에 따른 지하부 생체중은 -10 kPa과 -20 kPa 처리구에서 다른 처리보다 뛰어났으며, 수확량 및 상서수량은 -10 kPa 처리구가 무관수구에 대비 약 47%가량 증수되었다. 3. 감자의 최적 관비량 설정을 위해 괴경 형성기와 괴경 비대기에 관비를 실시한 결과 관비 처리 전후 지상부의 생육을 비교한 상대생장률은 K 5 및 NPK 0.8배 관비구에서 생육이 가장 우수하였고, 대조구(무관비구, 기비만 시용) 대비 감자 지상부 상대 생장률은 K 5, K 7, NPK 1.2배 관비구에서 가장 우수하였다. 4. 관비 처리에 따른 감자 지하부 생체중 및 수량, 상서수량을 비롯한 다수의 조사항목에서 K 5 처리구가 가장 우수하였고, 수량도 K 5 처리구가 대조구 대비 약 27%가량 증수되었다.

• 원예과학기술지
• /
• 제34권3호
• /
• pp.495-509
• /
• 2016

Irrigation applications (IA) and increased bud load (BL) are fundamental practices that are used to achieve optimum yields in grape production, while maintaining fruit quality parameters. Two different irrigation amounts (IA-I and IA-II) based on growth stages, in addition to a non-irrigated (rain-fed) control, along with two different BL applications [normal bud load based on traditional pruning practices (1BL) and double bud load (2BL)] were evaluated over a two-year experiment for their effects on the biochemical composition of the berries. Berries from the rain-fed vines had higher sugar levels, whereas no significant change was detected in organic acid levels. The increased bud load (2BL) treatment yielded less sugar in the berries compared to the 1BL control in both years. The total non-colored phenolic compounds (NPC) were greater in the irrigated (especially IA-I) and 2BL treatments than in those of the rain-fed and 1BL control. However, total anthocyanin was greater in the non-irrigated and 1BL control than in the irrigated and 2BL treatments. The antioxidant contents of the berries also varied according to the treatments and years. Our results implied that implementing a higher bud load along with the IA-I irrigation application, in which irrigation applications were 50 and 75% of the cumulative evaporation from the Class A pan during berry set to veraison and veraison to harvest growth stages, respectively, can help in obtaining greater yields in high-plateau viticulture. Thus, if more buds are left on the vines, along with sufficient irrigation and rainfall, yield may increase while maintaining or increasing the biochemical composition of the berries.

• 생물환경조절학회지
• /
• 제29권3호
• /
• pp.245-251
• /
• 2020

본 시험은 저면관수 방식의 파프리카 육묘 시 암면큐브에 대한 다양한 급액시점 (IP 30%, 40% 50%, 60% 및 70%)에 따른 파프리카 묘의 소질을 조사하였다. 급액시점에 따른 파프리카 묘의 생육량은 급액시점과 정의상관을 나타내었다. 특히 IP 30~40% 처리구와 IP 50~70% 처리구들 간 뚜렷한 차이를 나타내었다. 엽면적은 50% 이상의 처리구에서 40%이하의 처리구에 비해 50~100%정도 더 넓었고, 건물중도 30%~60% 정도 더 무거웠다. IP 50% 이상 처리구에서 건물 중의 유의한 차이는 없었다. 급액시점(X)은 파프리카 묘의 엽면적(Y₁)과 Y₁=48.311x+133.7(R² = 0.9116^⁎⁎), 건물중(Y₂)과는 Y₂=0.1584x+0.8616(R² = 0.8853^⁎)의 선형회귀관계를 나타내었다. 따라서 본 연구 조건에서 파프리카 육묘 시 처리 간 엽면적과 건물생산량을 고려하였을 때 수분함량 100%인 암면큐브 무게의 50%에 급액하는 것이 적합하고 경제적일 것으로 생각된다.