Effect of different drip irrigation regimes on sugar beet (Beta vulgaris L.) yield, quality and water use efficiency in Middle Anatolian, Turkey

Agricultural production has forced researchers to focus on increasing water use efficiency by improving either new drought-tolerant plant varieties or water management for arid and semi-arid areas under water shortage conditions. A field study was conducted to determine effects of seasonal deficit irrigation on plant root yield, quality and water use efficiency (WUE) of sugar beet for a 2-year period in the semi-arid region. Irrigations were applied when approximately 50–55% of the usable soil moisture was consumed in the effective rooting depth at the full irrigation (FI) treatment. In deficit irrigation treatments, irrigations were applied at the rates of 75, 50 and 25% of full irrigation treatment on the same day. Irrigation water was applied by a drip irrigation system. Increasing water deficits resulted in a relatively lower root and white sugar yields. The linear relationship between evapotranspiration and root yield was obtained. Similarly, WUE was the highest in DI25 irrigation conditions and the lowest in full irrigation conditions. According to the averaged values of 2 years, yield response factor (k _y ) was 0.93 for sugar beet. Sugar beet root quality parameters were influenced by drip irrigation levels in both years. The results revealed that irrigation of sugar beet with drip irrigation method at 75% level (DI25) had significant benefits in terms of saved irrigation water and large WUE, indicating a definitive advantage of deficit irrigation under limited water supply conditions. In an economic viewpoint, 25% saving of irrigation water (DI25) caused 6.1% reduction in the net income.     

Responses of winter wheat (Triticum aestivum L.) evapotranspiration and yield to sprinkler irrigation regimes

The North China Plain (NCP) is one of the main productive regions for winter wheat (Triticum aestivum L.) and summer maize (Zea mays L.) in China. However, water-saving irrigation technologies (WSITs), such as sprinkler irrigation technology and improved surface irrigation technology, and water management practices, such as irrigation scheduling have been adopted to improve field-level water use efficiency especially in winter wheat growing season, due to the water scarcity and continuous increase of water in industry and domestic life in the NCP. As one of the WSITs, sprinkler irrigation has been increasingly used in the NCP during the past 20 years. In this paper, a three-year field experiment was conducted to investigate the responses of volumetric soil water content (SWC), winter wheat yield, evapotranspiration (ET), water use efficiency (WUE) and irrigation water use efficiency (IWUE) to sprinkler irrigation regimes based on the evaporation from an uncovered, 20-cm diameter pan located 0-5 cm above the crop canopy in order to develop an appropriate sprinkler irrigation scheduling for winter wheat in the NCP. Results indicated that the temporal variations in SWC for irrigation treatments in the 0-60-cm soil layer were considerably larger than what occurred at deeper depths, whereas temporal variations in SWC for non-irrigation treatments were large throughout the 0-120-cm soil layer. Crop leaf area index, dry biomass, 1000-grains weight and yield were negatively affected by water stress for those treatments with irrigation depth less than 0.50E, where E is the net evaporation (which includes rainfall) from the 20-cm diameter pan. While irrigation with a depth over 1.0E also had negative effect on 1000-grains weight and yield. The seasonal ET of winter wheat was in a range of 206-499 mm during the three years experiments. Relatively high yield, WUE and IWUE were found for the irrigation depth of 0.63E. Therefore, for winter wheat in the NCP the recommended amount of irrigation to apply for each event is the total 0.63E that occurred after the previous irrigation provided total E is in a range of 30-40 mm.     

Evapotranspiration and crop coefficients of rice (Oryza sativa L.) under sprinkler irrigation in a semiarid climate determined by the surface renewal method

The evapotranspiration (ET_c) of sprinkler-irrigated rice was determined for the semiarid conditions of NE Spain during 2001, 2002 and 2003. The surface renewal method, after calibration against the eddy covariance method, was used to obtain values of sensible heat flux (H) from high-frequency temperature readings. Latent heat flux values were obtained by solving the energy balance equation. Finally, lysimeter measurements were used to validate the evapotranspiration values obtained with the surface renewal method. Seasonal rice evapotranspiration was about 750–800 mm. Average daily ET_c for mid-season (from 90 to 130 days after sowing) was 5.1, 4.5 and 6.1 mm day^?1 for 2001, 2002 and 2003, respectively. The experimental weekly crop coefficients fluctuated in the range of 0.83–1.20 for 2001, 0.81–1.03 for 2002 and 0.84–1.15 for 2003. The total growing season was about 150–160 days. In average, the crop coefficients for the initial (K_cini), mid-season (K_cmid) and late-season stages (K_cend) were 0.92, 1.06 and 1.03, respectively, the length of these stages being about 55, 45 and 25 days, respectively.     

不同喷灌水氮组合对马铃薯耗水、产量和品质的影响

为了探讨黑龙江省克山县圆形喷灌机条件下不同水氮组合对马铃薯的耗水规律、产量和品质的影响,同时确定节水、节肥、高产目标下适宜的水氮组合方式,试验设置了2个灌水水平:灌水总量W1(80 mm)和W2(100 mm);4个追氮量水平:F1(45 kg/hm²),F2(56.6 kg/hm²),F3(70 kg/hm²)和F4(86.6 kg/hm²);2个施氮频次:C1为块茎膨大期1次施入,C2为块茎膨大期分2次施入,并选择雨养区作为对照.结果表明:马铃薯全生育期耗水量为313~332 mm,块茎膨大期耗水量最大,占全生育期耗水总量63.4%~66.0%,幼苗期和块茎形成期是需水关键期,应结合马铃薯生长状况和当地雨水情况,适当进行补充灌溉;相比于其余处理,W2F4C2处理产量最高,达到46 525 kg/hm²;不同水氮组合间马铃薯的淀粉、维生素C、粗蛋白含量及商品薯率无显著差异,粗蛋白含量随着施氮量的增加呈现先降低后升高的趋势.综合比较,建议在黑龙江半湿润地区,可采用高水(100 mm)高肥(86.6 kg/hm²)高频次(块茎膨大期分2次施入)的方案.     

Responses of cowpea (Vigna unguiculata (L.) Walp.) and mung bean (Vigna radiata (L.) Wilczek) to irrigation

Summary Cowpea and mung bean were subjected to three irrigation schedules during summer dry months (May–June). In general, cowpea had higher rates of net photosynthesis (P _n ,Figs. 1, 2), dark respiration (R _d ,Table 1), absorption of photosynthetically active radiation (PAR, Table 2), and growth (Fig. 7) than mung bean. Mung bean reflected more PAR and maintained a slightly cooler canopy than cowpea (Table 2). Moisture stress decreased P _n , R _d ,absorption coefficient of PAR, evaporative cooling and growth in both the species. However, the reductions in P _n rates of stressed leaves were more than the decreases in R _d .Restoration of water supply to stressed cowpea resulted in a more rapid recovery of growth as compared to mung bean.     

Crop water use of onion (Allium cepa L.) in Turkey

In a greenhouse pot experiment conducted in Turkey during 2001, onion seedlings were transplanted on May 31 at the density of five plants per pot. On this date the soil water content of all pots were at field capacity. The pots were weighed daily until harvest (December 2), and the data were used to determine the daily evapotranspiration and quantity of irrigation. Eight irrigation treatments were applied, designated as I₁ full irrigation (non-deficit treatment), and I₂, I₃ and I₄ no irrigation in the vegetative growth periods, yield formation and ripening, respectively, and I₅, I₆, I₇ and I₈ received 0.0, 0.25, 0.50 and 0.75 times the soil water depletion in the treatment I₁ on the same day. For each treatment, the following parameters were analysed and compared: applied irrigation depth, daily and seasonal evapotranspiration, bulb yield, yield response factor (k_y), irrigation water use efficiency (IWUE) and water use efficiency (WUE). The findings indicated that onion plants were very sensitive to lack of soil water during the total growing season and the yield formation period, but rather insensitive in the vegetative and ripening periods. High water use and water use efficiencies were observed with increasing levels of irrigation, or no irrigation in the vegetative period.     

微机自动化在节水工程中的应用及推广探析

为了推动农业经济增长方式的根本性转变,促进传统家业向现代化农业转变,变粗放经营为集约经营,加快农业产业化进程,增加水利投入的科技含量,提高资源利用率,就必须采取高为发展节水灌溉,以取代传统的农业灌溉方式,本文介绍了微机自动化在日光温室微灌和大田灌溉试验工程中应用。详细分析了试验工程的社会效益和经济效益及其不可取代的优越性。充分论证微机自动化应用于节水灌溉工程不但有利于社会化大农业生产,而且为改善农     

Deficit irrigation of sunflower (Helianthus annuus L.) in a sub-humid climate

The response of sunflower (Helianthus annuus L.) to 14 irrigation treatments in a sub-humid environment (Bursa, Turkey) was studied in the field for two seasons. A rainfed (non-irrigated) treatment as the control and 13 irrigation treatments with full and 12 different deficit irrigations were applied to the hybrid Sanbro (Novartis Seed Company) planted on clay soil, at three critical development stages: heading (H), flowering (F) and milk ripening (M). The yield increased with irrigation water amount, and the highest seed yield (3.95 t ha⁻¹) and oil yield (1.78 t ha⁻¹) were obtained from the HFM treatment (full irrigation at three stages); 82.9 and 85.4% increases, respectively, compared to the control. Evapotranspiration (ET) increased with increased amounts of irrigation water supplied. The highest seasonal ET (average of 652 mm) was estimated at the HFM treatment. Additionally, yield response factor (k _y) was separately calculated for each, two and total growth stages, and k _y was found to be 0.8382, 0.9159 (the highest value) and 0.7708 (the lowest value) for the total growing season, heading, and flowering-milk ripening combination stages, respectively. It is concluded that HFM irrigation is the best choice for maximum yield under the local conditions, but these irrigation schemes must be re-considered in areas where water resources are more limited. In the case of more restricted irrigation, the limitation of irrigation water at the flowering period should be avoided; as the highest water use efficiency (WUE) (7.80 kg ha⁻¹ mm⁻¹) and irrigation water use efficiency (IWUE) (10.19 kg ha⁻¹ mm⁻¹) were obtained from the F treatment.     

Response of green bean (P. vulgaris L.) to subsurface drip irrigation and partial rootzone-drying irrigation

Effects on water use, green bean yield, irrigation water-use efficiency (IWUE), water-use efficiency (WUE), plant dry weight and crop water relationship were investigated for two-drip irrigation techniques and four irrigation water levels in the Mediterranean region of Turkey. The treatments were conventional (SDI) and alternating subsurface drip irrigation (SPRD). At each irrigation event, half of the volume of water applied to the SDI was applied to one side of the crop, representing the partial rootzone-drying treatment. All treatments received 295 mm of irrigation during crop establishment, prior to beginning the different irrigation regimes. Differing irrigation amounts corresponded to four crop-pan coefficients (Kcp₁ = 0.6, Kcp₂ = 0.8, Kcp₃ = 1.0 and Kcp₄ = 1.2), appropriate to pan data. Total water applied to the SDI and SPRD treatments ranged from 366 to 437 mm and from 331 to 366 mm, respectively, depending on Kcp values, with water uptake varying from 396 to 470 mm and 364 to 409 mm, respectively. While differences of green bean yield and dry plant weights were not significantly affected by the SDI and SPRD irrigation techniques, the overall irrigation water saving was found to be 16% for the SPRD irrigation treatment compared with the SDI treatment. SPRD irrigation techniques increased IWUE, WUE, and slopes of yield water relationships. Increase in slopes of the yield–irrigation water and yield–water-use function of SPRD according to the equivalent slopes of the SDI were 215.8 and 151.4%, respectively. SPRD increased the green bean yield response factor (ky) with value of 128.4% according to the equivalent slopes of the SDI. In conclusion, irrigation scheduling based on a 0.8 crop-pan coefficient is recommended for conventional SDI, with 1.0 being more appropriate for partial rootzone-drying practice.     

Yield and quality of two tomato (Solanum lycopersicum L.) cultivars as influenced by drip and furrow irrigation using waters having high residual sodium carbonate

Performance of tomato when irrigated with sodic waters particularly under drip irrigation is not well known. A field experiment was conducted for 3 years to study the response of tomato crop to sodic water irrigation on a sandy loam soil. Irrigation waters having 0, 5 and 10 mmol_c L⁻¹ residual sodium carbonate (RSC) were applied through drip and furrow irrigation to two tomato cultivars, Edkawi (a salt tolerant cultivar) and Punjab Chhuhara (PC). High RSC of irrigation water significantly increased soil pH, ECe and exchangeable sodium percentage progressively; the increases were higher in furrow compared to drip irrigation. Effect of high RSC on increasing bulk density and decreasing infiltration rate of soil was also pronounced in furrow-irrigated plots. Higher soil moisture and lower salinity near the plant was maintained under drip irrigation than under furrow irrigation. Performance of the two cultivars was significantly different; pooled over 2002–03 and 2003–04 seasons, PC yielded 38.8 and 30.0 Mg ha⁻¹ and Edkawi yielded 31.8 and 22.9 Mg ha⁻¹ under drip and furrow irrigation, respectively. At RSC10, cultivar PC produced 38 and 46% higher fruit yield than cultivar Edkawi under drip and furrow irrigation, respectively. Reduction in fruit yield at higher RSC was due to lower fruit weight under drip irrigation and due to reduced fruit number as well as fruit weight under furrow irrigation. Decrease in fruit weight was more pronounced in cultivar Edkawi than in cultivar PC. Increase in RSC lowered quality of the fruits except the ascorbic acid content. High RSC under drip irrigation, in general, had lesser deteriorating effect on the fruit quality particularly for cultivar PC than under furrow irrigation. For obtaining high tomato yield and better-quality fruits using high RSC sodic waters, drip irrigation should be preferred over furrow irrigation. Better performance of local cultivar PC compared to Edkawi at medium and high RSC suggests that cultivars categorized as tolerant to salinity should be evaluated in the sodic environment particularly when irrigated with high RSC sodic waters.     

中国喷灌机现状与发展思考

基于水利统计数据,分析了近10 a中国节水灌溉应用分布,发现东北以喷灌为主,西北以微灌为主,华北以低压管灌为主,华东以渠道灌溉为主,具有明显的区域特征,节水灌溉仍有50%发展空间,喷灌技术占比与欧美国家相比仍然偏低.总结回顾了中国喷灌机发展历程、研究进展和发展趋势.从国家政策引导、智慧农业发展、农业种植结构变化和盐碱地耕地改造4个方面,分析了在资源环境约束挑战下中国喷灌机的发展机遇.阐明了喷灌的优势和不可替代作用,指出随着中国高标准农田建设及农业规模化经营稳步推进,喷灌机性能及功能不断增强,使以往喷灌的局限性逐步转变成发展优势.最后从补齐农业全程机械化短板、水肥药一体化作业新模式和无人化智能化方面展望了中国喷灌机未来发展前景.     

The Effect of supplemental irrigation and nitrogen fertilisation on wheat (Triticum aestivum L.)

Summary Four irrigation treatments: no irrigation; early irrigation (150 mm); late irrigation (150 mm); and early+late irrigation (275 mm), with 363 mm of rain; and four basic applications of nitrogen (0, 60, 120, 180 kg ha^–1), with and without an additional nitrogen top dressing of 60 kg ha^–1, were applied to autumn-sown wheat.For any given total nitrogen rate, there was no difference between the single and the split application.Grain yields ranged from 3040 kg ha^–1 for the unirrigated, zero-nitrogen treatment to 6340 kg ha^–1 for the two irrigations, 180 kg ha ^–1 N treatment. There was a strong interaction of irrigation and nitrogen on grain yields which was due mainly to the late irrigation: in the absence of the late irrigation the optimal nitrogen rate was 120 kg hat, followed by a marked decline in yield with additional nitrogen, whereas the application of the late irrigation shifted the optimum nitrogen rate to 180 kg ha^–1. In the absence of the late irrigation, increasing the nitrogen rate from 0 to 240 kg ha ^–1 reduced kernel weight from 42 to 32 mg, whereas late irrigation largely prevented this decrease (42 to 39 mg). The reduction in kernel weight was evident even at the first nitrogen increments, in the range where grain yield was still increasing. Lack of nitrogen reduced soil moisture extraction during the grain filling stage, particularly from soil layers deeper than 60 cm.Stomatal aperture in the irrigated treatments was markedly larger in nitrogen-supplied than in nitrogen-deficient wheat, although the leaf hydration was similar; in the unirrigated treatment, the nitrogen-supplied plants had a lower hydration and smaller stomatal aperture than nitrogen-deficient plants.Contribution from the Agricultural Research Organization, Bet Dagan, Israel, No: 282-E, 1977 series     

中国轻小型喷灌机组现状及发展建议

为了提高中国轻小型喷灌机组的技术水平,全面分析中国轻小型喷灌机组的研究现状和未来的发展趋势.轻小型喷灌机组是中国应用比较广泛的一种喷灌机具,在农田灌溉、排涝抗旱及生态环境建设等方面发挥着较为重要的作用.经过40多年的发展,中国的轻小型喷灌机组已经具有多种机组型式,可满足各种地形条件、投资水平及劳动力状况等不同场合应用.目前国产机组的水力性能较好,部分配套件质量达到或超过国外同类产品水平,但产品的可靠性、使用寿命和外观等与国外产品仍存在较大差距.中国农业生产力水平和经济发展状况决定了在未来较长时间内,轻小型喷灌机组在节水灌溉设备行业仍有较高的市场份额.因此,国家应加大扶持力度,支持开展轻小型喷灌机组配套模式、机械化技术、低能耗技术和使用可靠性的开发研究,进一步提高轻小型喷灌机组的技术水平.     

浙江省推广喷滴灌技术措施

浙江省推广喷滴灌技术,采用了以下3种做法:一是技术创新,采用单元小型化、管径精准化、肥药简约化等多项措施,降低了喷滴灌工程造价;二是应用创新,把喷滴灌应用于竹笋、杨梅、水稻(育秧)等30多种作物,并应用于灌水,施肥、施药、除霜、除雪,淋洗沙尘等多种用途, 还用于猪兔羊、鸡鸭鹅、石蛙蚯蚓等养殖场降温、消毒,提高了综合效益;三是政府主导,通过制订规划、增加投资、技术培训,加快了喷滴灌技术推广.     

Regional analysis of irrigation water requirements using kriging: Application to potato crop (Solanum tuberosum L.) at Trás-os-Montes

Aiming at the analysis of the regional variation of potato crop irrigation water requirements over the Trás-os-Montes region, data from 106 rainfall stations and eight weather stations were utilized in an irrigation scheduling simulation model to estimate net irrigation water requirements of the potato crop. The simulation model was first validated using a field experiment which allows to derive the required crop data to be used in the simulations. The reference evapotranspiration (ET₀) was estimated using the FAO Penman–Monteith method. The model was applied to all 106 locations, each with a data set spanning a 19-year period. As a result of this application, series of the net irrigation water requirements for a 19-year period were obtained for each location. The resulting 106 point values of the net water requirements of the potato crop have been treated as a regionalized variable. The respective semivariograms have been computed and the kriging method then applied to estimate the spatial distribution of the water requirements in the region. Contour lines of this regionalized variable have been drawn using a GIS system. Results show an estimation error averaging 5% for the entire region.     

喷灌发展与土地经营模式的思考

发展喷灌要因地制宜，采用与土地经营模式相适应的喷灌形式是保证喷灌生命力的一个重要前提。通过对国内外发展喷灌中采用的主要形式及其土地经营模式的分析，总结了国内外喷灌发展中的经验。针对我国现行的农村生产体制，对我国喷灌发展的提出了个人的见解；改进现有机型，发展适合我国农村土地经营模式的喷灌设备，从而促进我国喷灌的健康发展。     

我国喷灌技术发展面临的主要问题及对策

我国喷灌的发展经历从引进到仿制创新,从自发研制到国家组织、计划攻关,在品种繁杂到系列化、标准化的过程,其中有高潮也有低谷.经过近40年的发展,我国的喷灌出现了设备生产混乱、性能差系列化程度低、自有技术少等一些问题,同样也存在投资与效益、制度与体制的问题.未来发展将主要集中在以下几个方面:低压低能耗、综合利用清洁能源、喷灌机组逐渐轻型化控制面积增大、自动控制和精量控制.文中提出我国喷灌发展的对策:一是开发适合我国国情的喷灌机组,降低价格,形成中国特色的喷灌系列产品;二是加大科研力度,拥有一批具有自主产权的专利技术;三是加快设备的研制与产业化进程;四是因地制宜地发展喷灌,讲求社会、生态和经济效益并举.     

Effect of drip irrigation frequency on radish (Raphanus sativus L.) growth and water use

Irrigation frequency is one of the most important factors in drip irrigation scheduling, and a proper irrigation frequency can establish moderate moist and oxygen conditions in the root zone throughout the crop period. Field experiments on the effects of irrigation frequency on radish growth and water use were carried out in 2001 and 2002. The experiment included six irrigation frequencies: once every day, once every 2 days, once every 3 days, once every 4 days, once every 6 days and once every 8 days. There was no significant difference among the six treatments on radish development and yield, but significant differences in radish roots distribution and market quality were found. Radishes irrigated once every 3 days had well-developed roots throughout the crop period, the lowest cracking rate and the least number of radishes of Grade 3. The observation results of lysimeter in 2002 showed that radish evapotranspiration decreased as irrigation frequency decreased, and the general changing tendency of 2-day ET of high irrigation frequency was related to that of 2-day evaporation. It is recommended that radish irrigation frequency should be once every 3 days and the irrigation amount should be estimated according to the evaporation of 20 cm diameter pan in the North China Plain.     

Comparative effects of partial root-zone drying and deficit irrigation on nitrogen uptake in potatoes (<Emphasis Type="Italic">Solanum tuberosum</Emphasis> L.)

The effects of partial root-zone drying (PRD) as compared with deficit irrigation (DI) and full irrigation (FI) on nitrogen (N) uptake and partitioning in potato (Solanum tuberosum L.) were investigated. Potato plants were grown in split-root pots and were exposed to FI, PRD, and DI treatments at tuber bulking stage. Just before onset of the irrigation treatment, each plant received 0.6 g N (in the form of urea) with 5% of which was ¹⁵N-labeled. After 4 weeks of irrigation treatments (i.e., one drying/wetting cycles completed in the PRD treatment), the plants were harvested and plant dry mass and N content were determined. The results showed that although the plant dry mass was not affected by the irrigation treatments, due to a reduced water use by the plant, both the PRD and DI treatments significantly increased crop water use efficiency. Compared with the FI and DI plants, PRD plants had significantly higher N contents in the leaves, stems and tubers; whereas, the ¹⁵N content in the plant organs was similar for the FI, PRD, and DI plants. It is suggested that not the root N uptake efficiency but the soil N availability was enhanced by the PRD treatment.     

轻小型喷灌机组的运行速率与压力水头损失

为研究轻小型喷灌机组低压喷灌条件下运行速率的合理取值以及工作压力与喷灌机组压力水头损失的关系,以轻小型喷灌机组为研究对象,经过室内喷灌试验,研究了一定工作压力和流量条件下机组的运行速率、灌水定额之间的关系,并对机组的局部水头损失和沿程水头损失进行了分析.结果表明:灌水定额与轻小型喷灌机组的运行速率、工作压力有一定的关系,通过确定灌水定额,能够调制出相应的运行速率.轻小型喷灌机组卷盘车处入口压力增大,喷水车单喷头处的压力也随之增大,但是入口压力增大到一定程度后,单喷头压力的提高幅度减小,因此在机组正常工作范围内,可以通过适当降低机组的入口压力,以减少机组的压力水头损失,节省能耗,降低机组的运行成本.轻小型喷灌机组在中国有广泛的发展前景,该项研究对于中国轻小型喷灌机组的性能改良具有重要意义,为轻小型喷灌机组的发展提供参考依据.