Effects Of Different Irrigation Treatments Research Articles

Effect of Different Irrigation Treatments on Yield, and Quality of Potato under North Sinai Conditions

Effect of Different Irrigation Treatments on Yield, and Quality of Potato under North Sinai Conditions

Hydraulic Trait Variation with Tree Height Affects Fruit Quality of Walnut Trees under Drought Stress

Persian or common walnut (Juglans regia L.) is a fruit tree of significant agricultural importance and is considered highly drought-resistant. However, the effects of different irrigation treatments and tree height on the physiology, growth and fruit quality of the walnut tree remain largely elusive. In the presently study, we selected ‘Wen 185’, one of the main walnut cultivars, as the target plant species. We established three irrigation treatments (deficit (DI), conventional (CI) and excess irrigation (EI)) from April to September of 2020 and measured leaf hydraulic traits, photosynthetic characteristics, soluble sugar (SS) content, leaf area, branch growth, fruit morphology and the no and deflated kernel (NDK) rate of walnut trees in each treatment. Our results showed that: (1) midday leaf water potential (Ψmd) decreased significantly under the DI treatment and declined significantly with increasing tree height; upper canopy Ψmd in the DI group decreased by 18.40% compared to the lower canopy; (2) the light compensation point, light saturation point, maximum net photosynthetic rate, maximum photochemical efficiency and chlorophyll SPAD values of trees in the DI group decreased slightly but did not differ significantly from the CI and EI treatments; (3) reduced irrigation did not significantly affect the soluble sugar content of leaves (LSs) and fine roots (RSs), but the soluble sugar content of walnut kernels (FSs) was significantly higher in the DI treatment than under the CI and EI treatments and also increased with tree height; the average soluble sugar content across heights was 6.61% in the EI group, 7.19% in the CI group and 9.52% in the DI group; (4) branch terminal leaf area (LA) was significantly reduced at the end of new branches, and Huber values (HV) were significantly higher under the DI treatment; compared to the EI group, LA was reduced by 52.30% in the DI group and 32.50% in the CI group; HV increased by 79.00% in the DI group and 15.70% in the CI group; (5) reduced irrigation did not significantly affect fruit morphology but did increase the NDK rate of walnuts, which also increased with tree height; the average NDK rate across all heights was 4.63% in the EI group, 5.04% in the CI group, and 8.70% in the DI group; the NDK rate was 41.75% higher in the upper part of the canopy compared to the lower part in the DI group. Our results indicate that walnut trees suffer greater water stress in the upper canopy than in the middle and low parts of the canopy. By increasing HV, walnut trees maintained relatively stable photosynthetic capacity under drought. However, water deficit had a significant effect on NDK rates, particularly at greater tree heights.

Impact of Wastewater Spreading on Properties of Tunisian Soil under Arid Climate

The environmental impacts of irrigating an olive field with olive mill wastewater (OMW) and treated wastewater (TWW) on soil properties were investigated. The effect of different irrigation treatments of OMW (50 m3 ha−1, 100 m3 ha−1, and 200 m3 ha−1) and TWW at different soil depths was studied. The obtained findings revealed that TWW application augmented soil pH; EC values; and P, K and Ca contents in all soil layers. However, Mg and Na concentrations, as well as organic matter content (OM), were proven to decrease with TWW irrigation throughout the experiment. Whereas soil adjusted with OMW showed a decrease in K, Ca, Mg and Na contents with soil depth, a significant increase was observed with the increase in applied OMW dose. On the other hand, total phenols and OM content increased significantly with the rise in OMW levels in all the investigated layers compared to the control sample.

Comparative Yield and Photosynthetic Characteristics of Two Corn (Zea mays L.) Hybrids Differing in Maturity under Different Irrigation Treatments

Effective irrigation strategies are of great significance for improving crop yields. There is an increasing concern that short-season corn hybrids are gradually being encouraged to plant in the North China Plain (NCP) with the development of mechanized grain harvesting, but the photosynthetic characteristics and productivity of short-season hybrids are not well documented. The objective of the study was to investigate the effects of different irrigation treatments on photosynthetic characteristics, dry matter accumulation (DMA) and photo-assimilate translocation (PAT/PT), grain yield (GY) and water productivity (WP) of two corn hybrids differing in maturity. In the experiment plots under the rainout shelter facility, short-season hybrid Denghai518 (DH518) and medium- and full-season hybrid Denghai605 (DH605) were grown under three irrigation levels (severe water stress, T1; mild water stress, T2; and non-stress, T3) by two irrigation methods (flood irrigation, FI; surface drip irrigation, SDI) in 2020 and 2021. The results indicated that non-stomatal limitation (NSL) was the main factor leading to the reduction in photosynthesis during the reproductive stage. Severe water stress significantly decreased net photosynthetic rate (Pn) and chlorophyll soil-plant analysis development (SPAD) value, resulting in lower DMA and GY. The contribution rate of vegetative organ photosynthate before flowering (CRP) decreased with the irrigation levels increasing. DMA, GY and WP of SDI increased by 16.23%, 21.49% and 51.31%, respectively, compared to FI. The yields of DH518 were 7.22% lower than those of DH605. The WP penalty for DH605 was attributed to a relatively larger ET. It suggested that applying the optimum irrigation level (T3) under SDI could increase DMA, GY and WP of summer corn in the NCP.

Application of infrared thermography for irrigation scheduling of horticulture plants

Infrared thermal imaging has acquired remarkable acceptance in the agricultural field for numerous applications ranging from irrigation scheduling, crop yield estimation, plant disease detection, fruit maturity evaluation, bruise detection to nursery monitoring. This paper presents a practical application of thermal imaging for irrigation scheduling of horticulture plants under different irrigation treatments. Four similar hibiscus potted plants were considered under different water conditions (slight, mild, moderate, and severe water stress). The thermal images were obtained from different canopy zones (front view, top view, left side view, right side view, and front angle view) using a ground-based hand-held thermal camera. The main objectives of the present study include (i) finding the effect of different irrigation treatments on potted plants and a corresponding change in their thermal signature, (ii) finding a relation between plant-based variables and soil-based variables, and to further develop a threshold value for irrigation scheduling (iii) to compare and simplify the calculation of the temperature of the canopy (Tc) and water stress indices namely crop water stress index (CWSI) and stomatal conductance index (Ig) using various reference and non-reference thresholding techniques and to improve their diagnostic accuracy. We can establish quantitative relationships between plant and soil-based parameters. The relationship between temperature of canopy (Tc) and temperature of soil (Ts) pair is best suited to find the plant under water stress. The threshold value pair (Tc and Ts) for the plants under study are 29.5°C (Tc) and 28°C (Ts) for plant A, 29.5°C (Tc) and 27.5°C (Ts) for plant B, 29.5°C (Tc) and 27°C (Ts) for plant C, and 29.5°C (Tc) and 26.5°C (Ts) for plant D. The most suitable method in terms of applicability and scalability, is histogram gradient thresholding (HG) method to determine Tc accurately. The critical m (for standard deviation envelope thresholding SDE method) and ratio of pixel change (RPC) (for HG method) value estimated can be considered an important indicator of water stress in the plants. Among different approaches to compute water stress indices, simplified and HG methods have minimum root mean square error (RMSE) for plants A, B, C, and D compared to statistical and SDE methods.

The effect of different irrigation treatments on yield and water productivity of Arachis Hypogaea L. under semi‐arid conditions in Iran

AbstractThe aim of this study was to assess the impacts of varied irrigation regimes on the yield, irrigation water productivity (IWP) and crop water productivity (CWP) of Arachis hypogaea L. under pressurized irrigation in the south‐west of Iran (Hamidiyeh, Khuzestan Province, Iran). The test was performed in a split‐plot pattern. The main treatments were three irrigation frequencies (Fs) based on varied levels of cumulative pan evaporation (CPE) amounts (F1: 35 mm; F2: 60 mm; F3: 85 mm of CPE). The subtreatments were seven irrigation water levels (Is) (I1 = 60%, I2 = 85%, I3 = 100%, I4 = 135% (of actual evapotranspiration (ETc)), I5 = PRZD60, I6 = PRZD85 and I7 = PRZD100 treatments) with four replications. The partial root‐zone drying (PRZD) treatments received 60, 85 and 100% of the actual evapotranspiration (ETc), respectively, from replacing laterals. Crops were planted on 1 June 2017 and 1 June 2018. The results indicated that the F2I4 treatment in both years showed the greatest peanut yield (PY). Moreover, in order to avoid greater PY loss the PRZD method was a proper and favourable option compared with traditional deficit irrigation (DI). However, PY declined by an average of 11.1 and 3.4% compared to the F2I4 treatment in 2017 and 2018, respectively, but the F2I7 treatment had about 16.3 and 16.1% lower water value than the F2I4 treatment. PRZD treatments (I5 and I6) have effective amended PY than deficit irrigation treatments (I1 and I2) in both growing seasons, whereas these treatments received the same amount of moisture for all Fs (F1, F2 and F3). In the end, crop water productivity and IWP amounts also declined with rising irrigation frequency. © 2020 John Wiley & Sons, Ltd.

Improving Yield and Quality of Processing Tomato (Lycopersicon esculentum Miller) Using Alternate Partial Root-Zone Drip Irrigation in Arid Northwest China

Processing tomato is one of the most important economic crops in Xinjiang, China, which was constrained with severe water shortage and extreme arid climate. Alternate partial root-zone irrigation (APRI) may provide an effective way to increase irrigation water use efficiency (iWUE) without yield reduction. However, limited studies concerned about applying APRI in processing tomato plantation have been done, especially combined with drip irrigation to further control the irrigation and improve iWUE. Therefore, the two-year pot experiments were conducted to study the effects of different irrigation treatments, including three APRI treatments (irrigation quota of 67.5, 51.6, and 43.7 mm, respectively), fixed partial root-zoon drip irrigation (FPRI, 67.5 mm) and conventional drip irrigation (CDI, 67.5 mm). The results indicated that APRI was an appropriate irrigation method in processing tomato plantation in arid desert area such as Xinjiang, as high irrigation quota of APRI (APRIH) significantly improved its yield without fruit quality reduction in comparison with those of CDI. However, the yield without fruit quality of FPRI significantly decreased. Even if the irrigation quota of APRI decreased to the medium level (APRIM, 51.6 mm), iWUE by increased 31.8–32.7% on the contrary, as irrigation water was saved by 23.6%; while keeping the yield and fruit quality. Therefore, APRIM is recommended for processing tomato plantation in arid northwest China, to increase plant growth, fruit quality, yield, and iWUE synergistically.

Effects of Different Irrigation Treatments on Aquaculture Purification and Soil Desalination of Paddy Fields

Aquaculture wastewater contains considerable quantities of organic matter, nitrogen, and phosphorus. Irrigation of paddy rice with aquaculture wastewater can make full use of water and fertilizer, which has practical significance for alleviating water-use conflicts in the coastal areas of Jiangsu Province and promoting soil desalinization. Our objective in this study was to evaluate the effects of water quality indexes of surface discharge in paddy fields, total nitrogen (TN) and total phosphorus (TP) losses of discharge in paddy fields, growing indexes of plants, grain yield, as well as soil salinity affected by the different irrigation treatments. To achieve this objective, experiments were conducted from May to October in 2017. There were four treatment combinations: I1W1 (shallow–frequent irrigation and aquaculture wastewater), I2W1 (shallow–wet irrigation and aquaculture wastewater), I3W1 (flooding irrigation and aquaculture wastewater), and I1W2 (shallow–frequent irrigation and fresh water). The results revealed that there was no significant difference in grain yield among the three wastewater irrigation treatments. Meanwhile, the values of water quality indexes were optimal in I3W1; the total losses of TN and TP of the I3W1 treatment were the lowest over the three important growth stages; the desalinization rate of I3W1 was the largest due to its long hydraulic retention time and large irrigation depth. The overall results suggested that the I3W1 treatment was the optimal treatment.

Effects of different irrigation levels on European corn borer (Ostrinia nubilalis (Hübner)) populations.

In In this study, the effects of different irrigation treatments (I100, I50, I30) on the European corn borer (Ostrinia nubilalis hübner) populations in different corn genotypes (Ada-9510, Samada-07, Ada-523, Kompozit Arifiye) were investigated. As the average, the highest yield (1582.33 kg da-1), low number of live larva + pupa per plant (2.70), tunnel length (7.73 cm) were observed in I100 x ADA-523 interaction while the lowest yield (896.00 kg da-1) was observed in I30 x Kompozit Arifiye interaction. The largest European corn borer population was observed in full irrigation (I100) and the lowest population was observed in excessive water deficit (I30) treatment. The European corn borer preferred the Kompozit Arifiye genotype. It was concluded that the genotypes should be tested under water-stressed and non-water-stressed conditions for resistance to the European corn borer and live larva and tunnel length could be used as a screening parameter.

Newly developed water productivity and harvest index models for maize in an arid region

Simulating yield response to different irrigation scenarios is important for agricultural production, especially in the arid region where agriculture depends heavily on irrigation. To better predict yield under different irrigation scenarios, the variation of normalized water productivity (WP*) over the whole growing period of maize for seed production and the effect of different irrigation treatments on harvest index (HI) were investigated using field experiments from 2012 to 2015 in an arid region of northwest China. Two new non-linear dynamic WP* (WP*KR-L and WP*KR-S) models derived from the Logistic and Sigmoid equations, and four new HI (HIKR-J, HIKR-M, HIKR-B and HIKR-S) models developed on the basis of water deficit multiplicative or additive models at different growth stages were compared with the measurements and the WP* (WP*AC) and HI sub-model (HIAC) in the original AquaCrop model (Version 4.0). In addition, the WP*AC and HIAC models in the original AquaCrop model were replaced by the optimal WP* and HI models to build the AquaCrop-KR model. Then the yield simulated by the AquaCrop-KR model was compared with the measured yield and the yield simulated by the original AquaCrop model. The results show that both WP*KR-L and WP*KR-S models improved the simulation of final biomass, especially for the WP*KR-L model. The tested HI sub-models, namely HIKR-J, HIKR-M, HIKR-B and HIKR-S models had good performance to simulate HI under different irrigation scenarios, and the HIKR-M model was the best among all tested sub-models. When both WP*KR-L and HIKR-M sub-models were embedded into Aquacrop, the performance of the AquaCrop model was improved significantly to simulate yield, especially under severe water stress condition, with R2 increased from 0.496 to 0.653, NRMSE decreased from 26.2% to 16.1% and EF increased from 0.055 to 0.642.

基于DSSAT模型对豫北地区夏玉米灌溉制度的优化模拟

PDF HTML阅读 XML下载 导出引用 引用提醒 基于DSSAT模型对豫北地区夏玉米灌溉制度的优化模拟 DOI: 10.5846/stxb201808101706 作者: 作者单位: 河南农业大学,河南农业大学农学院,河南农业大学农学院,河南农业大学农学院,河南农业大学农学院,南阳市宛城区种子管理站,河南农业大学农学院,浚县丰黎种业有限公司,河南农业大学农学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划项目（2017YFD0301106）；国家自然科学基金项目（31471452，31601258） Optimizing the summer maize irrigation schedule in North Henan Province based on the DSSAT model Author: Affiliation: Henan Agricultural University,Agronomy College of Henan Agricultural University,Agronomy College of Henan Agricultural University,Agronomy College of Henan Agricultural University,Agronomy College of Henan Agricultural University,Seed Management of Wancheng District, Nanyang, Henan, China,Agronomy College of Henan Agricultural University,Xunxian Fengli seed Industry Co. Ltd., Hebi, Henan, China,Agronomy College of Henan Agricultural University Fund Project: the National Key Research and Development Program of China (No. 2017YFD0301106), the National Natural Science Foundation of China (No. 31471452 and No. 31601258) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:合理的灌溉制度是提高农业水资源利用效率、保证夏玉米高产稳产的前提。采用农业技术转化决策系统（DSSAT，Decision Support System for Agrotechno1ogy Transfer）探究了河南省北部地区夏玉米不同降水年型下的最优灌溉制度。经过参数的校正和验证，归一化均方根误差（nRMSE）、均方根误差（RMSE）和一致性指数（d）均表现出模拟值与实测值的吻合度很好，DSSAT-maize模型可以准确模拟夏玉米物候期、地上部分生物量、产量和土壤水分状况。然后基于模型模拟了不同灌溉处理下的夏玉米生产潜力，从而评估夏玉米缺水量，并对比分析不同生育时期灌水对产量的影响确定最优灌溉时期，综合考虑产量和水分利用效率确定最优灌溉制度。结果表明：夏玉米生长季的缺水量年际间差异显著，多年平均值为38.91 mm，波动范围为0-193.03 mm。在丰水年，不需要灌溉；在平水年，开花期灌水30 mm；在枯水年，开花期和灌浆期灌水50 mm；在特别干旱年，苗期、拔节期和开花期至少灌水180 mm。优化的灌溉制度下丰水年、平水年和枯水年的WUE达到最高且产量分别占其最高产量的100%、99.72%和97.89%，实现了作物高产节水协同提高的目标。 Abstract:Henan Province is the main summer maize production area in China; however, the yield of maize in this region has been seriously threatened by water scarcity. It is important to improve maize yield and stability by appropriate irrigation allied to high water-use efficiency (WUE). In this study, we applied the Decision Support System for Agrotechnology Transfer (DSSAT) to determine the optimal irrigation schedules for summer maize in different hydrological years in the northern region of Henan Province. The GLUE procedure together with normalized root mean square errors (nRMSE), root mean square errors (RMSE), and index of agreement (d) showed that DSSAT-maize can be used to correctly predict maize yield, phenology, aboveground biomass, and soil water content. A calibrated model was used to simulate the effects of different irrigation treatments on the yield potential of summer maize in different hydrological years, and to evaluate the water shortages during the summer maize growing season. The optimal irrigation period was determined by comparing yield responses with different irrigation amounts and times, thereby enabling optimization of the irrigation schedule with yield and WUE. The results showed that water shortage in the summer maize growing season has varied significantly for the period of 1988-2017, averaging 38.91 mm, with a variation of 0 to 193.03 mm. In wet years, irrigation was unnecessary. Irrigation of 30 mm at the flowering stage should be applied in normal years and 50 mm at the flowering and grain-filling stages in dry years. In extraordinary dry years, irrigation of at least 180 mm should be applied at the emergence, jointing, and flowering stages of summer maize. Under the optimized irrigation schedule, when WUE reached the highest level in wet, normal, and dry years, the yield obtained accounted for 100%, 99.72%, and 97.89% of the maximum yield, respectively. The optimized irrigation schedule would produce a higher summer maize yield with the highest WUE. 参考文献 相似文献 引证文献

Crop Growth Modeling-a New Data-driven Approach

Deficit irrigation strategies have been employed in mitigation of challenges related to efficient water use in crop production. Various models have been developed to represent the behavior of plants under water stress conditions. This work presents a state-machine-based model that defines plant behavior in terms of states and transitions which are determined by both current and historical water status of the plant. The model is employed in prediction of the growth of maize plants under different irrigation treatments during the vegetative stage. The new approach provides an accurate estimation of the growth performance of maize plants during the early vegetative phase, allowing it to be used in evaluation of effects of different irrigation treatments and in design of irrigation-based plant control.

Improving the Growth of Rapeseed (Brassica chinensis L.) and the Composition of Rhizosphere Bacterial Communities through Negative Pressure Irrigation

Negative pressure irrigation (NPI) is a new water supply technology that can save water and improve fertilizer utilization efficiency. The objective of this study was to determine the effects of different irrigation treatments on the yield and quality of rapeseed, nitrate distribution in soil, and the composition of rhizosphere bacterial communities in a greenhouse. During the entire rapeseed growth period, NPI reduced water consumption by 23 and 23% compared to that reduced by conventional irrigation (CI) and drip irrigation (DI), and NPI improved water use efficiency (WUE) by 67 and 59% more than CI and DI, respectively. Under NPI, the soil water content remained relatively stable within the range of 9.7–11.7%, which was a lower range of variation than that under CI and DI of 8.6–13.3%. NPI significantly improved the yield, quality, and plant nutrients of rapeseed. The NO3-N content was always lowest at the different sampling times and soil layers under the NPI-L treatment. NPI significantly increased the microbial diversity in the rhizosphere soil of rapeseed and increased the abundance of Actinobacteria while decreasing that of Proteobacteria and Acidobacteria. Simultaneously, the performance of rapeseed was better under the NPI-L fertilizer concentration (0.15%) than under NPI-H (0.20%). Eventually, the combination of the evaluated regimes demonstrated that NPI is the best irrigation technique for saving water and obtaining relatively high rapeseed yields and quality while improving nitrogen utilization and the composition of rhizosphere bacterial communities. The results of this study provide a scientific basis for planting rapeseed in agricultural facilities.

Effects of different irrigation treatments during heading and flowering stage on cold resis-tance, yield and physiological characteristics of late rice

Taking super hybrid rice variety 'Wufengyou T025' as test material, the effects of different irrigation methods and water layer depth on physiological characteristics and yield in double-season late rice under low temperature conditions during heading and flowering stage were investigated. Three treatments were set, i.e., draining during day and containing 4-5 cm water layer during night (H1), draining during day and containing 8-10 cm water layer during night (H2), and containing 8-10 cm water layer day and night (H3), with the 0-1 cm water layer day and night was as the control (CK). The results showed that rice leaf temperature, soil layer temperature and canopy temperature under the different irrigation treatments were higher than that of CK, and the warming effect of treatment H2 was the best during the low temperature period. Leaf chlorophyll content, net photosynthetic rate, transpiration rate, leaf stomatal conductance and intercellular CO2 concentration of rice plants decreased gradually under the low temperature, while the smallest reduction occurred in H2. The increase ranges of malondialdehyde and proline content in H2 were lower, while its soluble protein content was the highest compared with other irrigation treatments. The increase ranges for the activities of superoxide dismutase and peroxidase in H2 were lower, while its decrease range for the activity of catalase was the lowest. Irrigation for heat preservation could increase the yield, and H2 performed best. Yield of H2 at the second sowing date in 2014 and 2015 encountering low temperature increased by 12.9% and 13.5% respectively compared to CK. The yield components including the effective panicle numbers per plant, panicle length, seed setting rate and 1000-grain mass were improved in all irrigation treatments compared to CK. Draining during day and containing 8-10 cm water layer during night (H2) was the most effective agronomic measure to enhance the tolerance to low temperature during heading and flowering stage for double-season hybrid late rice.

Spatial distribution of soil water, soil temperature, and plant roots in a drip-irrigated intercropping field with plastic mulch

Intercropping and drip irrigation with plastic mulch are two agricultural practices used worldwide. Coupling of these two practices may further increase crop yields and land and water use efficiencies when an optimal spatial distribution of soil water contents (SWC), soil temperatures, and plant roots is achieved. However, this coupling causes the distribution of SWCs, soil temperatures, and plant roots to be more complex than when only one of these agricultural practices are used. The objective of this study thus was to investigate the effects of different irrigation treatments on spatial distributions of SWCs, soil temperatures, and root growth in a drip-irrigated intercropping field with plastic mulch. Three field experiments with different irrigation treatments (high T1, moderate T2, and low T3) were conducted to evaluate the spatial distribution of SWCs, soil temperatures, and plant roots with respect to dripper lines and plant locations. There were significant differences (p < 0.05) in SWCs in the 0–40 cm soil layer for different irrigation treatments and between different locations. The maximum SWC was measured under the plant/mulch for the T1 treatment, while the minimum SWC was measured under the bare soil surface for the T3 treatment. This was mainly due to the location of drippers and mulch. However, no differences in SWCs were measured in the 60 100 cm soil layer. Significant differences in soil temperatures were measured in the 0 5 cm soil layer between different irrigation treatments and different locations. The soil temperature in the subsoil (15 25 cm) under mulch was higher than under the bare surface. The overlaps of two plant root systems in an intercropping field gradually increased and then decreased during the growing season. The roots in the 0 30 cm soil layer accounted for about 60% 70% of all roots. Higher irrigation rates produced higher root length and weight densities in the 0 30 cm soil layer and lower densities in the 30 100 cm soil layers. Spatial distributions of SWCs, soil temperatures, and plant roots in the intercropping field under drip irrigation were significantly influenced by irrigation treatments and plastic mulch. Collected experimental data may contribute to designing an optimal irrigation program for a drip-irrigated intercropping field with plastic mulch.

Changes in seed vigor of safflower (Carthamus tinctorius L.) cultivars during maturity in response to water limitation

&lt;p&gt;Seed development and vigor may be influenced by environmental stresses such as water deficit. Thus, this research was carried out to evaluate the effects of different irrigation treatments and harvest times on seed vigor of four spring safflower cultivars. Treatments were irrigations (irrigations after 70, 100, 130 and 160 mm evaporation, respectively) in main plots and safflower cultivars (Faraman, Goldasht, Sina and Soffeh) in sub-plots. Seeds were harvested in 5 days intervals at 7 stages during development and maturity. The highest and the lowest seed and seedling masss at all harvests and irrigation treatments were recorded for Faraman and Sina cultivars, respectively. Seed vigor of safflower cultivars as measured by electrical conductivity of seed leachates and seedling dry mass decreased with decreasing water availability. Maximum seed mass and seedling dry mass and minimum electrical conductivity were obtained at 40-45 days after flowering, depending on irrigation interval and cultivar. Seed moisture content at these stages was 15-20 %, which is suitable for direct and mechanical harvesting and threshing.&lt;/p&gt;

WATER USE EFFICIENCY, YIELD AND YIELD COMPONENTS OF SECOND CROP SUNFLOWER UNDER DEFICIT IRRIGATION

This study was conducted to observe the effects of different irrigation treatments on yield and yield components of second crop sunflower (Helianthus annuus L.) grown in western Turkey in 2012 and 2013. Trials comprised of two irrigation intervals (4-day and 8-day) and six different water levels (125, 100, 75, 50, 25 and 00% of cumulative Class-A pan evaporation on a 4-day and 8-day interval basis) were investigated. Seasonal water use values varied between 191.1-662.6 mm in 2012 and 194.0-675.8 mm in 2013. Interactions between irrigation interval and irrigation levels were found to be significant for seed yield in both years. Maximum and minimum seed yield were obtained from the 8-day IL-100 and 8-day IL-00 treatments as averaging 5072.6 kg ha-1 and 2327.9 kg ha-1 , respectively. Significant curvilinear relationships between seed yield and crop water use were obtained for 2012 and 2013. Water use efficiency and irrigation water use efficiency values were influenced by the irrigation intervals and levels. Water use efficiency varied from 1.21 kg m-3 to 0.70 kg m-3 among treatments in both years. The yield response factor (ky) was determined to be 0.70 for 4-day irrigation interval and 0.69 for 8-day irrigation interval. Deficit and frequent irrigation caused a remarkable decline in all yield components (head diameter, stem diameter, plant height, 1000 seed weight and oil yield) investigated in both experimental years. The yield components decreased as irrigation levels decreased for each irrigation interval. The IL-100 treatment in 8-day irrigation interval could be proper for sunflower irrigated in semi-arid regions under no water shortage and the 8-day IL-75 treatment could be used as a good basis for reduced drip irrigation strategy development under water shortage.

Effect of Different Irrigation Treatments on Growth and Development of Schefflera arboricola, (Hayata) Kanehira

Effect of Different Irrigation Treatments on Growth and Development of Schefflera arboricola, (Hayata) Kanehira

Effects of Different Irrigation Treatments on Maize Water Consumption, Growth and Yield under Film Hole Irrigation

Through film hole irrigation test-pit experiments,the effects of different irrigation treatments on water consumption,growth characteristics and maize yield were studied.The result showed that the jointing stage and heading stage were the key stages of water requirement of maize.Water consumption increased with the increased irrigation quota at the same number of irrigation.Effect of irrigation treatment on maize biological index was significant in less irrigation times and less irrigation quota.Water production efficiency increased 23.3% and yield increased 15.9% under film hole irrigation than that of border irrigation.Water consumption of the maximum yield was 3410m3/hm2 under film hole irrigation.

Effect of different irrigation treatments and plant density on yield and yield components of Dragon’s head (Lallemantia iberica Fish. et Mey.)

In order to investigate the effect of different irrigation treatments and plant density on yield and yield components of Dragon’s head (Lallemantia iberica Fish. et Mey.), an experiment was carried out as split-plot based on randomized complete block design with four replications at the Research Farm of the Faculty of Agriculture, University of Tabriz, Iran in 2012. Irrigation treatments (I1, I2, I3, I4 and I5: irrigation after 70, 100, 130, 160 and 190 mm evaporation from class A pan, respectively) were assigned to main plots and four plant density levels (D1, D2, D3 and D4: 200, 300, 400, 500 plant/m2) were allocated to the sub plots. Biological and grain yield, number of lateral stem, number of grain and capsule per plant, number of capsule per lateral stem, 1000 grain weight and harvest index were recorded. Results showed that irrigation treatments had significant effects on all of the characteristics with the exception of harvest index and 1000 grain weight. Means compression showed that highest biological and grain yield, numbers of lateral stem, numbers of capsule per plant, number of capsule per lateral stem, number of grain per plant were achieved under I1 treatments. Plant density did not have significant effects on biological yield and 1000 grain weight. Irrigation after 70 mm evaporation from class A pan produced more grain yield, but difference between I1 and I2 treatments was not significant. The greatest grain yield was obtained from 400 plant/m2. According to the results obtained, irrigation after 100 mm evaporation from class a pan and density of 400 plant/m2 is the best combination for Dragon’s head grain production.