Tomato Water Use Efficiency Research Articles

Yield, fruit quality and water use efficiency of tomato for processing under regulated deficit irrigation: A meta-analysis

Tomato is one of the most widely grown vegetables in the world because of special nutritive value of its fruit. Regulated deficit irrigation (RDI) is widely applied in tomato production due to the water shortage. A lot of studies demonstrated that certain degree of deficit irrigation decreased the tomato yield but improved the fruit quality. The purpose of this paper is to use a meta-analysis to: 1) estimate the effect of RDI on processing tomato yield, water use efficiency and fruit quality; 2) identify soil texture, growth stage and deficit severity that benefit yield and increase water use efficiency compared to full irrigation. We analyzed 25 research articles with 561 experimental groups and 145 control groups. Overall, RDI decreased processing tomato yield with mean difference of 18.61 t ha-1, increased water use efficiency with mean difference of 2.33 kg m-3, and improved fruit quality. The yield decreased with mean difference of 19.79 t ha-1 in loamy soil and 14.26 t ha-1 in non-loamy soil. The soil texture had no significant effects on yield and water use efficiency under severe RDI. Application of RDI at the first stage is recommended because of no significant yield loss and significant increase of water use efficiency. RDI can improve processing tomato total soluble solids and Vitamin C. Moreover, both of them were increased more when RDI was applied at the third stage than at previous two stages. Our findings can be helpful on how to use RDI correctly to balance the processing tomato yield, water conservation and fruit quality.

Establishing Irrigation Levels Targeting Higher Content of Lycopene and Water Use Efficiency in Tomato

The demand for healthier foods has been increasing worldwide. Associated with this trend, it is crucial to optimize the use of inputs for ensuring the sustainability of production. The fruits of tomato are important sources of minerals, vitamins, and especially of carotenoids such as the lycopene. This carotenoid plays biological activities that are crucial such as the antioxidant function, besides its proven action in the prevention of cancers and degenerative diseases. The irrigation seems to play a fundamental role in the biosynthesis of lycopene. Thus, it is fundamental to establish levels of irrigation that might provide higher content of lycopene, productivity, and efficiency in the use of water in the production of tomato. The objective of this study was to establish adequate levels of irrigation for the obtainment of higher content of lycopene, productivity of fruits, and higher efficiency in the use of water in the production of salad tomato. For this, two experiments were carried in different cropping seasons. The treatments consisted of the application of four irrigation depths, corresponding to 50, 100, 150 and 200% of the tomato evapotranspiration. The estimates of maximum productivity corresponded to the application of the irrigation depth of 112% ETc, while the maximum content of lycopene and the higher efficiency in the use of water corresponded to 50% ETc. The irrigation depth of 100% ETc is recommended as the best irrigation depth to obtain higher content of lycopene, productivity, and efficiency in the use of water jointly.

Simulation of Stomatal Conductance and Water Use Efficiency of Tomato Leaves Exposed to Different Irrigation Regimes and Air CO2 Concentrations by a Modified "Ball-Berry" Model.

Stomatal conductance (gs) and water use efficiency (WUE) of tomato leaves exposed to different irrigation regimes and at ambient CO2 (a[CO2], 400 ppm) and elevated CO2 (e[CO2], 800 ppm) environments were simulated using the “Ball-Berry” model (BB-model). Data obtained from a preliminary experiment (Exp. I) was used for model parameterization, where measurements of leaf gas exchange of potted tomatoes were done during progressive soil drying for 5 days. The measured photosynthetic rate (Pn) was used as an input for the model. Considering the effect of soil water deficits on gs, an equation modifying the slope (m) based on the mean soil water potential (Ψs) in the whole root zone was introduced. Compared to the original BB-model, the modified model showed greater predictability for both gs and WUE of tomato leaves at each [CO2] growth environment. The models were further validated with data obtained from an independent experiment (Exp. II) where plants were subjected to three irrigation regimes: full irrigation (FI), deficit irrigation (DI), and alternative partial root-zone irrigation (PRI) for 40 days at both a[CO2] and e[CO2] environment. The simulation results indicated that gs was independently acclimated to e[CO2] from Pn. The modified BB-model performed better in estimating gs and WUE, especially for PRI strategy at both [CO2] environments. A greater WUE could be seen in plants grown under e[CO2] associated with PRI regime. Conclusively, the modified BB-model was capable of predicting gs and WUE of tomato leaves in various irrigation regimes at both a[CO2] and e[CO2] environments. This study could provide valuable information for better predicting plant WUE adapted to the future water-limited and CO2 enriched environment.

Combined effects of deficit irrigation and strobilurin application on gas exchange, yield and water use efficiency in tomato (Solanum lycopersicum L.)

Abstract Water is the major factor limiting plant productivity in many regions of the world. The aim of this study was to evaluate the combined effect of deficit irrigation (restitution of 100%, 50% and 0% of plant consumption: WR100, WR50 and WR0, respectively) and strobilurin treatment (no agrochemical added vs azoxystrobin treatment) in two tomato genotypes, IT-22/025, a wild-type plant, and Ikram, a commercial hybrid. Water use efficiency (WUE), physiological, yield and quality parameters and the expression of ERD15, a gene involved in abiotic stress response were evaluated. The two genotypes showed a different behaviour in response to water stress. Stomatal conductance decrease from WR100 to WR50 was in mean 27.5% for IT-22/025 and 44.5% for Ikram. Moreover, in Ikram, water stress decreased transpiration more than assimilation rate, while the opposite occurred in IT-22/025. The ERD15 expression decrease from WR100 to WR50 was higher for IT-22/025. These effects corresponded to higher total fresh fruit yield and WUE for IT-22/025. Strobilurin determined lower stomata conductance, maintaining higher assimilation rate, leading to an increase in WUE in WR0. Finally, strobilurin caused an increase in ERD15 expression only in IT-22/025. This study underlines the possibility to reduce the water used in tomato crop, maintaining acceptable yield and quality, by using agronomic and genetic strategy.

嫁接对不同灌水量下番茄产量及水分利用率的影响

为探索番茄的嫁接节水栽培方式，试验设定常规灌水量、85%灌水量和70%灌水量，研究嫁接对不同灌水量下的番茄产量和水分利用率的影响。结果表明：随着灌水量的降低，番茄的产量降低，水分利用率提高；85%和70%灌水条件下，嫁接番茄水分利用率比自根番茄分别提高了15.6%和14.5%；在不影响产量的前提下，嫁接条件下可节约番茄生产用水15%左右。 In order to explore the cultivation method for saving water of tomato grafting, the effects of grafting on yield and water use efficiency of tomato under different irrigation amount were studied by setting normal irrigation, 85% irrigation amount and 70% irrigation amount. The results show that with the decrease of irrigation, tomato yield was reduced and water use efficiency was increased; Water use rate of grafted tomato were increased by 15.6% and 14.5% under 85% and 70% irrigation; 15% of tomato irrigation water can be saved by grafting without affecting the yield.

Yield, quality, nutrient and water use efficiency of tomato as affected by different fertigation rates through drip irrigation system

An experiment was carried out to study the impact of drip fertigation in tomato crop at RCA, MPUAT, Udaipur during rabi season 2015-16 in split plot designed with three irrigation schedules [100 (I1), 75 (I2) and 50% PE (I3) through drip] and five fertilization schedules [100% RDF (F1), 75% RDF (F2), 75% RDF + 2 foliar spray of 1% urea phosphate (F3), 50% RDF (F4), 50% RDF + 2 foliar spray of 1% urea phosphate (F5)]. Higher number of nodes per plant (21.20 and 19.89) and yield (169.03 and 186.38 q/ha) were registered with treatments receiving drip irrigation at 75% PE and 75% RDF through fertigation + 2 foliar spray of 1% urea phosphate, respectively. Quality characteristics were enhanced with combined use of I2F3 treatment. The highest water use efficiency i.e. 26.37 ka/ha-cm was recorded under I3F3 treatment and fertilizer use efficiency with I2F5 treatment combination (165.78, 254.31 and 381.46 kg/kg NPK, respectively).

Impacts of Kaolin and Pinoline foliar application on growth, yield and water use efficiency of tomato (Solanum lycopersicum L.) grown under water deficit: A comparative study

Abstract The impacts of Kaolin particle film (KPF) and Pinoline (P) Antitranspirants (ATs) on growth, yield components (marketable and unmarketable), fruit quality and on-farm irrigation water use efficiency (WUE) of tomato plants ( Solanum lycopersicum L. ) grown under water deficit of 40%, 60%, and 80% depletion of available water (DAW) were studied, to determine if ATs application would mitigate water deficit stress and increase WUE. The field experiments were elaborated in the open field for two seasons under the drip irrigation system. The results revealed that deficit irrigation (DI) significantly reduced the relative water content of the leaves (RWC), CO 2 assimilation rate (P-net), marketable yield, while canopy temperature (CT) and WUE were increased. Results indicated that KPF under DI effectively enhanced the physiological activities and marketable yield production, while reduced sunscald fruits and those with blossom-end rot symptoms (unmarketable yield), particularly under 60%DWA, but it did not compensate the negative effects under 80%DWA. Also, the effect was null under non-limiting water conditions. Generally, P had no significant effects under different water stress severities. Under 60%DWA, application of KPF increased the marketable yield to 93% of the unstressed-unsprayed plants, while conserving 25% of irrigation water, leading to an increase in WUE by 26.24% with respect to unstressed-unsprayed plants.

Growth, Water Use, and Nitrate-15N Uptake of Greenhouse Tomato as Influenced by Different Irrigation Patterns, 15N Labeled Depths, and Transplant Times.

Increasing water use efficiency and reducing nitrogen pollutant discharge are important tasks for modern agriculture. To evaluate the effect of alternate partial root-zone irrigation (APRI) on tomato plant growth, water use efficiency and nitrate-15N uptake, an experiment was conducted from June to December in 2014 under greenhouse condition in northern China. The experiment contained two irrigation patterns [APRI and conventional irrigation (CI)], two 15N labeled depths in soil (10 and 50 cm) and two transplant time (early and late summer). Results showed that, compared to CI, APRI did not significantly (p > 0.05) impact the growth and biomass accumulation in aboveground part of tomato, while it enhanced the root, reflecting by greater length density, and more dry mass. APRI produced marginally lower yields, but saved 34.9% of irrigation water, and gave a 37.6–49.9% higher water use efficiency relative to CI. In addition, APRI improved fruit quality, mainly through increasing the contents of soluble solid (by 12.8–21.6%), and vitamin C (2.8–12.7%), and the sugar/acid ratio (3.5–8.5%). The 15N utilization efficiency (15NUE) in APRI was higher than that in CI, which was more evident when 15N was labeled at 50 cm depth. Significant (p < 0.05) 15N recovery increase of 10.2–13.2% and 15N loss decrease of 35.4–54.6% were found for APRI compared to CI. The overall results suggest that APRI under greenhouse could benefit the nitrate-N recovery and increase the water use efficiency in tomato.

Effects of Low Salinity Stress on Growth, Yield and Water Use Efficiency of Tomato under Soilless Cultivation

Effects of Low Salinity Stress on Growth, Yield and Water Use Efficiency of Tomato under Soilless Cultivation

Improving agronomic water use efficiency in tomato by rootstock-mediated hormonal regulation of leaf biomass

Water availability is the most important factor limiting food production, thus developing new scientific strategies to allow crops to more efficiently use water could be crucial in a world with a growing population. Tomato is a highly water consuming crop and improving its water use efficiency (WUE) implies positive economic and environmental effects. This work aimed to study and exploit root-derived hormonal traits to improve WUE in tomato by grafting on selected rootstocks. Firstly, root-related hormonal parameters associated to WUE were identified in a population of recombinant inbred lines (RILs) derived from the wild tomato species Solanum pimpinellifolium. A principal component analysis (PCA) revealed that some hormonal traits were associated with productivity (plant biomass and photosynthesis) and WUE in the RIL population. Leaf ABA concentration was associated to the first component (PC1) of the PCA, which explained a 60% of the variance in WUE, while the ethylene precursor ACC and the ratio ACC/ABA were also associated to PC1 but in the opposite direction. Secondly, we selected RILs according to their extreme biomass (high, B, low, b) and water use (high, W, low, w), and studied the differential effect of shoot and root on WUE by reciprocal grafting. In absence of any imposed stress, there were no rootstock effects on vegetative shoot growth and water relations. Finally, we exploited the previously identified root-related hormonal traits by grafting a commercial tomato variety onto the selected RILs to improve WUE. Interestingly, rootstocks that induced low biomass and water use, ‘bw’, improved fruit yield and WUE (defined as fruit yield/water use) by up to 40% compared to self-grafted plants. Although other hormonal factors appear implicated in this response, xylem ACC concentration seems an important root-derived trait that inhibits leaf growth but does not limit fruit yield. Thus tomato WUE can be improved exploiting rootstock-derived hormonal signals which control leaf growth.

Effect of irrigation regime and application of kaolin on yield, quality and water use efficiency of tomato

Modern agriculture is faced with two tasks: (1) to produce enough food for a growing global population, and (2) to ensure satisfactory crop quality while using water resources efficiently. A study of the effect of kaolin on the yield, quality and water use efficiency of tomato (Lycopersicon esculentum Mill.), grown under different irrigation regimes, is reported in the paper. The research was conducted in an open field with carbonate chernozem soil, at Stara Pazova (40km north of Belgrade, Serbia). It lasted for three years (2011, 2012, and 2013). The experimental setup was a two-factorial, completely random block system, with three replications. The first factor was the irrigation regime and the second the application of kaolin. Two irrigation treatments were studied: (a) full irrigation (F), covering 100% of ETc (crop evapotranspiration), and (b) deficit irrigation (D) at 50% of ETc. The kaolin treatments were: (a) control treatment, without kaolin (C) and treatment with a 5% suspension of kaolin (K).On average, the highest fresh tomato fruit yields were achieved under full irrigation, with kaolin (FK) (21.0kgm−2). The FK treatment also resulted in the greatest dry weight of the fruits (1.1kgm−2). The average fruit weight was rather uniform and ranged from 71.7g with DC to 75.4g with DK. The average sugar and lycopene content was quite uniform over the study period, while the irrigation regime had a significant effect on the average organic acid content and total antioxidant activity. Deficit irrigation treatments resulted in a higher organic acid content and higher total antioxidant activity than full irrigation. The application of kaolin had a greater effect of the water use efficiency of tomato than the irrigation treatment.

Growth and yield promoting effect of artificial mycorrhization on field tomato at different irrigation regimes

Plant inoculation with formulations of vesicular–arbuscular mycorrhiza (VAM) can be a sustainable technique for the improvement of tomato yield and plant resistance to biotic and abiotic stresses. Combination of artificial plant mycorrhization with water deficit irrigation could be an effective agronomical technique for the optimization of water use efficiency of tomato in the areas with a limited water availability. A 2-year research on field tomato was undertaken in Southern Italy (40°24′N; 16°48′E; 10m a.s.l.) to evaluate the effects on crop growth, yield, and fruit quality of the combination of seedling inoculation with two VAM formulations, alone or integrated with plant growth promoting rhizobacteria (PGPR), with different irrigation regimes (restoration of 0%, 50%, and 100% of maximum crop evapotranspiration). A split-plot experimental design with three reps was followed, with irrigation regimes in the main plots and mycorrhizal treatments in the subplots. Both VAM treatments, either with or without PGPR, demonstrated to be highly and rapidly effective on plant growth, as significantly increasing growth of tomato seedlings and plant biomass at mid and end of both crops compared to the non-inoculated control. Positive effects of mycorrhizal inoculation were extended also to marketable yield, mainly as a result of an increased number and weight of fruits. Both VAM inocula did not significantly affect fruit quality parameters, though increased water use efficiency of marketable yield. Both irrigation regimes positively affected tomato growth and marketable yield, whereas the fruit quality was better in less- and non-watered plants. Adversely to expectations, no synergism was found between artificial mycorrhization and irrigation regimes.

Semi-determinate growth habit adjusts the vegetative-to-reproductive balance and increases productivity and water-use efficiency in tomato (Solanum lycopersicum)

Tomato (Solanum lycopersicum) shows three growth habits: determinate, indeterminate and semi-determinate. These are controlled mainly by allelic variation in the SELF-PRUNING (SP) gene family, which also includes the “florigen” gene SINGLE FLOWER TRUSS (SFT). Determinate cultivars have synchronized flower and fruit production, which allows mechanical harvesting in the tomato processing industry, whereas indeterminate ones have more vegetative growth with continuous flower and fruit formation, being thus preferred for fresh market tomato production. The semi-determinate growth habit is poorly understood, although there are indications that it combines advantages of determinate and indeterminate growth. Here, we used near-isogenic lines (NILs) in the cultivar Micro-Tom (MT) with different growth habit to characterize semi-determinate growth and to determine its impact on developmental and productivity traits. We show that semi-determinate genotypes are equivalent to determinate ones with extended vegetative growth, which in turn impacts shoot height, number of leaves and either stem diameter or internode length. Semi-determinate plants also tend to increase the highly relevant agronomic parameter Brix×ripe yield (BRY). Water-use efficiency (WUE), evaluated either directly as dry mass produced per amount of water transpired or indirectly through C isotope discrimination, was higher in semi-determinate genotypes. We also provide evidence that the increases in BRY in semi-determinate genotypes are a consequence of an improved balance between vegetative and reproductive growth, a mechanism analogous to the conversion of the overly vegetative tall cereal varieties into well-balanced semi-dwarf ones used in the Green Revolution.

Effect of Different Levels of Irrigation and Nutrient Management Practices on the Performance of Tomato (Lycopersicon esculentumL.)

To study the effect of different levels of irrigation and nutrient management practices on yield and water use efficiency of tomato (cv. Utkal Kumari) a field experiment, with three irrigation schedules and four nutrient management practices, was conducted in the Regional Research Technology and Transfer Station (RRTTS), Chiplima, Sambalpur for three years. Three years pooled mean of tomato fruit yield indicated that highest fruit yield of 18.48 t ha−1 was observed with IW: CPE of 1.2 irrespective of different nutrient management practices. Highest pooled mean fruit yield of 19.07 t ha−1 was recorded with application of 25% organic+75% inorganic which was significantly superior to 50% organic+50% inorganic (18.26 t ha−1), 100% organic (16.01 t ha−1) and 100% inorganic (17.21 t ha−1) irrespective of different irrigation levels. Highest mean water use efficiencies of 533.45 kg ha−1 cm−1 and 469.47 kg ha−1 cm−1 were observed with IW: CPE of 0.8 and application of 25% organic+75% inorganic fertilizer respectively. Among the irrigation treatments highest net return ( 56, 136/-) and benefit-cost ratio (2.03) were observed with 1.2 IW: CPE, whereas the highest net return ( 61, 560/-) and benefit-cost ratio (2.16) were observed with 25% organic+75% inorganic fertilzer. Thus, integrated use of 25% organic along with 75% inorganic fertilizer as per recommended dose of nutrient with an irrigation scheduling at 1.2 IW: CPE produced highest fruit yield of tomato as compared to other treatments. The fruit yield per hectare was significantly correlated to all other yield attributing parameters except days to first harvest.

Effects of Different Irrigation Amount on Yield and Quality of Greenhouse Tomatoes

In order to determine the proper irrigation amount of summer tomatoes,taking drip irrigation in green house,5 irrigation volume including 990 m3/hm2、1485 m3/hm2、1980 m3/hm2(CK)、2475 m3/hm2、2970 m3/hm2were set,and the effects of different irrigation amount on the yield and quality of tomato in greenhouse were studied. The results showed that with the increase of irrigation amount,the soluble solid content,titratable acid content,Vc content and irrigation water use efficiency of tomato decreased. In treatment T1, T4, T5 ,yield decreased by 26.3%, 6.5%, 15.8%. In treatment T2 , the yield decreased by 1.9%,while the irrigation water use efficiency increased by 20.8%,and the soluble solids content,titratable acid content and Vc content increased.It is concluded that the optimum irrigation amount is 1485 m3/hm2.

IRRIGATION APPLICATION DEPTHS AND POTASSIUM DOSES ON TOMATOES UNDER PROTECTED ENVIRONMENT IN SOUTHEAST BRAZIL

Modern irrigation water and nutrient management strategies improve crop yields and lead to optimum profits. The objective of the study was to evaluate effects of irrigation depths and potassium doses on production, quality and water use efficiency of tomato ( Lycopersicon esculentum Mills) under protected environment condition. The treatments consisted of irrigation water levels equivalent to 50, 75, 100, and 125% of crop water requirement (CWR) with potassium doses of 208, 416 and 624 kg ha -1 . A drip irrigation system was used for fertigation of potted Debora Plus tomato variety. Irrigation, potassium doses and its interaction with irrigation levels had significant effects on total, commercial and non commercial production. Marketable yields reached a maximum of 64.4 mg ha -1 at 416 kg ha -1 of potassium, produced at 75% CWR. This corresponded to an average irrigation rate of 4.72 mm day -1 . Higher potassium dose of 624 kg ha -1 depressed total and commercial yields. Tomato fruit pH values were between 4.0 and 4.5 for all treatments, while the highest total soluble solids were 9.2%, found with irrigation level of 75% CWR. Maximum water use efficiency was 12.4 kg m -3 of applied water, also obtained at 75% CWR. An irrigation reduction of 25% CWR could hence optimize water resources and save significant water quantities through improved efficiency of water applications to the plant.

Effects of partial root-zone irrigation on physiology, fruit yield and quality and water use efficiency of tomato under different calcium levels

Abstract Partial root-zone irrigation (PRI) is an irrigation technique to save irrigation water without much yield reduction. We investigated if the benefits of PRI on physiology, fresh fruit yield, fruit quality and water use efficiency (WUE) of pot-grown tomato could be modified by different calcium (Ca) levels in the greenhouse. Three irrigation methods, i.e. conventional irrigation (CI), alternate partial root-zone irrigation (APRI, alternate watering on both sides of the pot) and fixed partial root-zone irrigation (FPRI, fixed watering on one side of the pot), and five Ca levels in solution, i.e. 0, 0.3, 0.5, 0.8 and 1.0% of Ca supplied as calcium chloride, were designed. Results show that PRI reduced more transpiration rate than photosynthetic rate, which led to higher leaf WUE. APRI enhanced root activity, increased fresh fruit yield of tomato slightly and WUE on fresh yield greatly. APRI increased the contents of VC and soluble sugar in fruits by 12.6 and 4.5% but decreased organic acid content in fruits by 5.3%, so APRI increased the ratio of sugar/acid and improved fruit quality greatly. However, FPRI reduced fresh fruit yield and quality to some extent. Suitable concentration of Ca fertilizer can increase photosynthetic rate, fresh fruit yield, WUE on fresh yield and fruit quality. Thus APRI with suitable concentration of Ca fertilizer is a water-saving, quality-improving and practical irrigation technology. In this study, APRI with 0.8% of Ca supplied as calcium chloride is the best treatment.

Drip irrigation and black polyethylene mulch influence on growth, yield and water-use efficiency of tomato

A two year field study was conducted during 2001-2002 and 2002-2003 on sandy loam soil to investigate the effect of drip irrigation and black polyethylene mulch compared with surface irrigation, on growth, yield, water-use efficiency and economics of tomato (Lycopersicon esculentum Miller.). Drip irrigation at 80% evapo-transpiration (ET) crop based on pan evaporation applied gave significantly higher fruit yield (45.57 tonnes/ha) compared with the surface irrigation (29.43 tonnes/ha). Use of black polyethylene mulch plus drip irrigation further raised the fruit yield to 57.87 tonnes/ha. Plant height, leaf area index, dry matter production, fruit weight and yield increased significantly with the use of drip irrigation alone and in conjunction with polyethylene mulch compared to surface irrigation alone or with mulch. Water-use efficiency under drip irrigation alone, drip irrigation with polyethylene mulch and surface irrigation was 0.97, 1.23 and 0.42 tonne/ha-cm, respectively. Among different irrigation levels, drip irrigation at 80% ET resulted in higher net returns (34431 Rs/ha) and benefit cost ratio (1.76) in tomato. However, maximum net returns (51386 Rs/ha) and benefit cost ratio (2.03) was found with drip irrigation at 80% ET coupled with polyethylene mulch compared to other treatments. Drip irrigation besides giving a saving of 38% water resulted into 55% higher fruit yield compared to surface irrigation. Key words: Drip irrigation, pan evaporation, black polyethylene, fruit yield, tomato

THE EFFECT OF IRRIGATION SYSTEMS AND DEFICIT IRRIGATION LEVELS ON PRODUCTIVITY AND WATER USE EFFICIENCY OF TOMATO CROP UNDER SANA'A BASIN CONDITIONS

Sana'a basin is located between latitude 16.8° and 17.4° northern and longitude 40° and 44° eastern; the elevation above the sea level is 2200m. Its climate is semi-arid, where its average rainfall is 235 mm/year. The total area of Sana'a basin is 320000 hectares and the cultivated area is estimated as 107000 hectares. The annual water consumption of agricultural irrigation in Sana'a basin is estimated as 180 million cubic meters, which withdraw from the conserved ground water through more than 6000 wells, whereas the shortage percentage of ground water recharge from the rainfall is 400%, which causes decreasing in the ground water level about 6 meter/year. The actual water requirements of irrigated crops are 70 million cubic meters, that means the traditional irrigation efficiency in Sana'a basin is not exceed 40%. The aim of this research is to increase the productivity and water use efficiency under Sana'a basin conditions. The research was studied the effect of different irrigation systems (drip-in, drip-on, furrow + hydrosol polymer, and furrow) and water supply levels (50, 75, and 100% deficit irrigation from actual requirement) on the productivity, water use, and water use efficiency of tomato crop under Sana'a basin conditions in Yemen. The study took place at the college of agriculture in experiment farm of university Sana'a on crop tomato. The experiment was designed according to split plot design. The statistical data analysis and formulating prediction equations for studied properties was done using computer program (SAS). The results of research are indicated – as sample: The effect of different irrigation systems was significant (p < 0.01) on the productivity, water use and water use efficiency of tomato. The highest productivity of tomato is found to be 31443.3kg/ha for furrow irrigation system with hydrosol polymer, whereas the lowest is found to be 24113.3kg/ha. While the lowest water use is found to be 397.16mm for drip-in irrigation system, whereas the highest is found to be 595.75mm for furrow irrigation system. While the highest water use efficiency is found to be 6.52 kg/m3 water for drip-on irrigation system, whereas the lowest is found to be 4.22 kg/m3 water for furrow irrigation system. The effect of water supply levels (deficit irrigation levels) was significant (p < 0.01) on the productivity, water use and water use efficiency of tomato. The highest productivity of tomato is found to be 30644.2kg/ha for 100% water supply level, whereas the lowest is found to be 21724.2kg/ha for 50% water supply level. While the lowest water use is found to be 330.98mm for 50% water supply level, whereas the highest is found to be 661.94mm for 100% water supply level. While the highest water use efficiency is found to be 6.77 kg/m3 water for 50% water supply level, whereas the lowest is found to be 4.76 kg/m3 water for 100% water supply level. The effect of interaction between irrigation systems and water supply levels were significant (p < 0.01) on water use, while the other studied properties were not significant. The lowest water use is found to be 264.78mm for drip-in irrigation system at 50% water supply level, whereas the highest is found to be 795mm for furrow irrigation system at 100% water supply level. The highest productivity is found to be 37667kg/ha for furrow irrigation system with hydrosol polymer at 100% water supply level, whereas the lowest is found to be 19887kg/ha for furrow irrigation system at 50% water supply level. The highest water use efficiency is found to be 7.78 kg/m3 water for drip-on irrigation system at 100% water supply level, whereas the lowest is found to be 3.43 kg/m3 water for furrow irrigation system at 100% water supply level.

Effect of partial rootzone drying on growth, gas exchange, and yield of tomato ( Solanum lycopersicum L.)

Three levels of partial rootzone drying (PRD) were evaluated and compared with conventional irrigation, in terms of gas exchange, water relations, growth, yield, fruit quality, and water use efficiency in tomato ( Solanum lycopersicum L.) saladette-type plants growing in pots with volcanic material and drip irrigation. There were four treatments, a control, in which available water (AW) in the whole root system was allowed to fall to 90%; PRD90-30, in which on one side of the divided root AW was allowed to fall to 90% and on the other side it was allowed to fall to 30%; PRD70-30, in which on one side of the divided root AW was allowed to fall to 70% and on the other side it was allowed to fall to 30%; PRD50-30, in which on one side of the divided root AW was allowed to fall to 50% and on the other side it was allowed to fall to 30%. When each treatment reached the desired AW level they were then irrigated. At the same time, when on one side AW reached values ≤30% irrigation was shifted to the other side. Results showed a significant decrease of leaf water potential up to 14% in PRD plants compared with control. Shoot dry weight and leaf area decreased in relation to substrate available water in PRD plants. Stomatal conductance and transpiration rate were lower, up to 31 and 18%, respectively, in plants with PRD compared with control. However, CO 2 assimilation rate was similar among treatments which along with the reduction of transpiration in PRD plants, increased instantaneous water use efficiency by 28, 25, and 33% in PRD90-30, PRD70-30, and PRD50-30 treatments, respectively, compared to control. Yield, number of fruits and fruit total soluble solids content were similar among treatments. An increase of 25% in fruit titratable acidity was reached in PRD50-30. Fruit firmness increased up to 31% in PRD treatments. PRD treatments allowed a water irrigation saving up to 46%.