Foliar Applications of Essential Nutrients on Growth and Yield of ‘Valencia’ Sweet Orange Infected with Huanglongbing

Huanglongbing (HLB) causes citrus root systems to decline, which in turn contributes to deficiencies of essential nutrients followed by decline of the canopy and yield. This study was conducted on a 6-year-old ‘Valencia’ [Citrus sinensis (L.) Osb.] on Swingle rootstock (Citrus paradisi Macf. × Poncirus trifoliata (L.) Raf.) trees in a commercial grove near Immokalee, FL, to evaluate the effects of foliar applications of selected essential nutrients (N, K, Mn, Zn, B, and Mg) on growth and productivity of citrus trees infected with Candidatus Liberibacter asiaticus (CLas), the pathogen putatively associated with HLB in Florida. Mn, Zn, B, and Mg were applied in all experiments to drip at 0×, 0.5×, 1.0×, and 2.0×/spray of what has been traditionally recommended in Florida to correct deficiencies. Treatments were applied foliarly 3×/year with the sprays occurring during each growth flush for 5 years (2010–14). Thus, the 0×, 0.5×, 1.0×, and 2.0×/spray treatments resulted in 0×, 1.5×, 3.0×, and 6.0×/year to correct deficiencies. MnS04 and ZnSO4 were applied with or without KNO3 and in separate experiments were compared with Mn3(PO3)2 and Zn3(PO3)2, respectively. Disease incidence, foliar nutrient content, canopy volume, and yield were measured. At the beginning of the experiment, foliar N, P, Ca, Mg, Cu, and B were in the sufficient range and K, Mn, Zn, and Fe were slightly low. Disease incidence was very high with 83% and 98% of trees testing positive for CLas in 2010 and 2014, respectively. Nutrients that are not mobile or have limited mobility in plants, namely Mn, Zn, and B, demonstrated an increase in foliar concentration immediately after spray and in the annual averages. Foliar K increased from the deficient to the sufficient level by KNO3 sprays, but the mobile nutrients N and Mg did not show an increase in foliar levels, indicating that intraplant transport occurs in the presence of HLB. Foliar KNO3 application had a stronger effect on growth than yield. Yield was most strongly affected by application of MnSO4 where yield of the 3×/year treatment was 45% higher than that of the unsprayed control, but yield declined by 25% for the 6×/year treatment. Yield within 95% of the maximum occurred with foliar Mn concentrations of 70–100 µg·g−1 dry weight when Mn was applied as MnSO4, which is at the high end of the traditionally recommended 25–100 µg·g−1 dry weight range. The phosphite form of Mn [Mn3(PO3)2] depressed yield by an average of 25% across all application concentrations. Zn, B, and Mg did not significantly impact yield. Canopy volume demonstrated concave relationships across application concentrations for MnSO4 and ZnSO4 without KNO3 and Mn3(PO3)2, Zn3(PO3)2, Boron, and MgSO4 with KNO3, with the minimum occurring near the 3×/year application concentration. These data indicate a complex interaction in the amount of nutrients applied and their corresponding effects on foliar concentration, growth, and yield for HLB-affected trees. The results of this study at least partially explain the current confusion among scientists and the commercial industry in how to manage nutrition of HLB-affected citrus trees. The traditionally recommended approaches to correcting nutrient deficiencies need to be reconsidered for citrus with HLB.

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Production of interstocked 'Pera' sweet orange nursey trees on 'Volkamer' lemon and 'Swingle' citrumelo rootstocks

Scientia Agricola ◽

10.1590/s0103-90162006000100002 ◽

2006 ◽

Vol 63 (1) ◽

pp. 5-10 ◽

Cited By ~ 6

Author(s):

Eduardo Augusto Girardi ◽

Francisco de Assis Alves Mourão Filho

Keyword(s):

Citrus Sinensis ◽

Sweet Orange ◽

Dry Weight ◽

Poncirus Trifoliata ◽

Production Cycle ◽

Citrus Paradisi ◽

Higher Plant ◽

Weight Percentage ◽

Volkamer Lemon ◽

Swingle Citrumelo

Incompatibility among certain citrus scion and rootstock cultivars can be avoided through interstocking. 'Pera' sweet orange (Citrus sinensis L. Osbeck) nursery tree production was evaluated on 'Swingle' citrumelo (Poncirus trifoliata (L.) Raf x Citrus paradisi Macf) and 'Volkamer' lemon (Citrus volkameriana Pasquale) incompatible rootstocks, using 'Valencia' and 'Hamlin' sweet oranges (Citrus sinensis L. Osbeck), 'Sunki' mandarin (Citrus sunki Hort. ex Tanaka), and 'Cleopatra' mandarin (Citrus reshni Hort. ex Tanaka) as interstocks. Citrus nursery trees interstocked with 'Pera' sweet orange on both rootstocks were used as control. 'Swingle' citrumelo led to the highest interstock bud take percentage, the greatest interstock height and rootstock diameter, as well as the highest scion and root system dry weight. Percentage of 'Pera' sweet orange dormant bud eye was greater for plants budded on 'Sunki' mandarin than those budded on 'Valencia' sweet orange. No symptoms of incompatibility were observed among any combinations of rootstocks, interstocks and scion. Production cycle can take up to 17 months with higher plant discard.

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Nutrient content of biomass components of Hamlin sweet orange trees

Scientia Agricola ◽

10.1590/s0103-90162003000100023 ◽

2003 ◽

Vol 60 (1) ◽

pp. 155-160 ◽

Cited By ~ 41

Author(s):

Dirceu Mattos Jr. ◽

José Antônio Quaggio ◽

Heitor Cantarella ◽

Ashok Kumar Alva

Keyword(s):

Nutrient Management ◽

Dry Weight ◽

Nutrient Content ◽

Poncirus Trifoliata ◽

Nutrient Concentrations ◽

Citrus Paradisi ◽

Fibrous Root ◽

Nutrient Distribution ◽

Biomass Components ◽

Orange Trees

The knowledge of the nutrient distribution in trees is important to establish sound nutrient management programs for citrus production. Six-year-old Hamlin orange trees [Citrus sinensis (L.) Osb.] on Swingle citrumelo [Poncirus trifoliata (L.) Raf. x Citrus paradisi Macfad.] rootstock, grown on a sandy Entisol in Florida were harvested to investigate the macro and micronutrient distributions of biomass components. The biomass of aboveground components of the tree represented the largest proportion of the total. The distribution of the total tree dry weight was: fruit = 30.3%, leaf = 9.7%, twig = 26.1%, trunk = 6.3%, and root = 27.8%. Nutrient concentrations of recent mature leaves were in the adequate to optimal range as suggested by interpretation of leaf analysis in Florida. Concentrations of Ca in older leaves and woody tissues were much greater than those in the other parts of the tree. Concentrations of micronutrients were markedly greater in fibrous root as compared to woody roots. Calcium made up the greatest amount of nutrient in the citrus tree (273.8 g per tree), followed by N and K (234.7 and 181.5 g per tree, respectively). Other macronutrients comprised about 11% of the total nutrient content of trees. The contents of various nutrients in fruits were: N = 1.20, K = 1.54, P = 0.18, Ca = 0.57, Mg = 0.12, S = 0.09, B = 1.63 x 10-3, Cu = 0.39 x 10-3, Fe = 2.1 x 10-3, Mn = 0.38 10-3, and Zn = 0.40 10-3 (kg ton-1). Total contents of N, K, and P in the orchard corresponded to 66.5, 52.0, and 8.3 kg ha-1, respectively, which were equivalent to the amounts applied annually by fertilization.

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FERTILIZER EFFECTS ON EARLY GROWTH AND YIELD OF 'HAMLIN' ORANGE TREES

HortScience ◽

10.21273/hortsci.27.6.595b ◽

1992 ◽

Vol 27 (6) ◽

pp. 595b-595

Author(s):

Thomas A. Obreza ◽

Robert E. Rouse

Keyword(s):

Maximum Rate ◽

Fruit Yield ◽

Tree Canopy ◽

Poncirus Trifoliata ◽

Soluble Solids ◽

Growth And Yield ◽

Fertilizer Rate ◽

Cross Sectional ◽

Canopy Volume ◽

K Fertilizer

The growth response of newly-planted 'Hamlin' orange (“Citrus sinensis L. Osbeck) on Carrizo citrange (C. sinensis × Poncirus trifoliata L. Raf.) trees to N-P-K fertilizer rates was studied to determine the minimum fertilizer required to bring trees into maximum early production. The highest fertilizer rate applied was 2.72, 5.45, and 8.17 kg·tree-1 of an 8-1.8-6.6 N-P-K fertilizer in 1989, 1990, and 1991, respectively. Additional fertilizer treatments equalled 50, 25, or 13% of the maximum rate. The response of trunk cross-sectional area, tree canopy volume, and fruit yield to fertilizer rate was described by a linear plateau model. The model predicted a fruit yield of 22.6 kg·tree-1 at the estimated critical rate of 48% of maximum. Fruit yield at 50% of maximum rate averaged 21.2 kg·tree. As fertilizer rate increased, total soluble solids (TSS) in juice and ratio (TSS:acid) decreased, but weight per fruit and TSS per tree increased. A fruit yield above 21 kg·tree-1 from 31-month-old trees was indicative of vigorous growth.

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Nitrogen, Calcium, and Magnesium Inconsistently Affect Tree Growth, Fruit Yield, and Juice Quality of Huanglongbing-affected Orange Trees

HortScience ◽

10.21273/hortsci15997-21 ◽

2021 ◽

pp. 1-10

Author(s):

Eduardo Esteves ◽

Gabriel Maltais-Landry ◽

Flavia Zambon ◽

Rhuanito Soranz Ferrarezi ◽

Davie M. Kadyampakeni

Keyword(s):

Tree Growth ◽

Defense Mechanisms ◽

Fruit Yield ◽

Poncirus Trifoliata ◽

Bacterial Disease ◽

Juice Quality ◽

Citrus Paradisi ◽

Canopy Volume ◽

Citrus Production ◽

N Rates

The bacterial disease Huanglongbing (HLB) has drastically reduced citrus production in Florida. Nutrients play an important role in plant defense mechanisms and new approaches to manage the disease with balanced nutrition are emerging. Nutrients like nitrogen (N), calcium (Ca), and magnesium (Mg) could extend the productive life of affected trees, although interactions among these nutrients in HLB-affected citrus trees are still unclear. A 2-year study was established in Florida to determine the response of HLB-affected trees to applications of N, Ca, and Mg. The study was conducted with ‘Valencia’ trees (Citrus sinensis L. Osbeck) on Swingle citrumelo (Citrus paradisi Macf. × Poncirus trifoliata L. Raf.) rootstock on a Candler sand. Applications of N at 168, 224 (recommended rate), and 280 kg⋅ha−1 N were used as the main plots. Split-plots consisted of a grower standard treatment receiving only basal Ca (51 kg⋅ha−1) and Mg (56 kg⋅ha−1); supplemental Ca (total Ca inputs: 96 kg⋅ha−1) only; supplemental Mg (total Mg inputs: 101 kg⋅ha−1) only; and supplemental Ca (total Ca inputs: 73.5 kg⋅ha−1) and Mg (total Mg inputs: 78.5 kg⋅ha−1). The following variables were measured: tree size, fruit yield, and juice quality. Although some differences in tree growth among treatments were statistically significant (e.g., greater canopy volume with Mg fertilization at 168 kg⋅ha−1 N), there was no clear and consistent effect of plant nutrition on these variables. Fruit yield was higher with Ca and Mg relative to the grower standard at the lowest N rate in 2020, and there were no other statistically significant differences among treatments. Juice acidity was significantly higher with Mg fertilization relative to other treatments in 2019. As N rates had no significant effect in this study, unlike secondary macronutrients, N rates could potentially be reduced to 168 kg N⋅ha−1 in HLB-affected citrus without affecting vegetative growth, fruit yield, and juice quality. However, this will require optimizing the supply of secondary macronutrients and all other nutrients to develop a balanced nutritional program. Ultimately, the effects of N, Ca, and Mg obtained in this 2-year study should be confirmed with longer-term studies conducted at multiple sites.

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Sweet orange trees grafted on selected rootstocks fertilized with nitrogen, phosphorus and potassium

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2004000100008 ◽

2004 ◽

Vol 39 (1) ◽

pp. 55-60 ◽

Cited By ~ 12

Author(s):

José Antônio Quaggio ◽

Dirceu Mattos Junior ◽

Heitor Cantarella ◽

Eduardo Sanches Stuchi ◽

Otávio Ricardo Sempionato

Keyword(s):

Poncirus Trifoliata ◽

Tree Planting ◽

Rangpur Lime ◽

Yield Efficiency ◽

Citrus Groves ◽

Canopy Volume ◽

Phosphorus And Potassium ◽

Orange Trees ◽

Low K ◽

Citrus Trees

The majority of citrus trees in Brazil are grafted on 'Rangpur lime' (Citrus limonia Osb.) rootstock. Despite its good horticultural performance, search for disease tolerant rootstock varieties to improve yield and longevity of citrus groves has increased. The objective of this work was to evaluate yield efficiency of sweet oranges on different rootstocks fertilized with N, P, and potassium. Tree growth was affected by rootstock varieties; trees on 'Swingle' citrumelo [Poncirus trifoliata (L.) Raf. × C. paradisi Macf.] presented the smallest canopy (13.3 m³ in the fifth year after tree planting) compared to those on 'Rangpur lime' and 'Cleopatra' mandarin [C. reshni (Hayata) hort. ex Tanaka] grown on the same grove. Although it was observed an overall positive relationship between canopy volume and fruit yield (R² = 0.95**), yield efficiency (kg m-3) was affected by rootstocks, which demonstrated 'Rangpur lime' superiority in relation to Cleopatra. Growth of citrus trees younger than 5-yr-old might be improved by K fertilization rates greater than currently recommended in Brazil, in soils with low K and subjected to nutrient leaching losses.

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595 Computer Root Image Analysis of Citrus Rootstock Seedlings

HortScience ◽

10.21273/hortsci.35.3.499d ◽

2000 ◽

Vol 35 (3) ◽

pp. 499D-499

Author(s):

Milton E. Tignor ◽

Peter J. Stoffella

Keyword(s):

Root Zone ◽

Dry Weight ◽

Poncirus Trifoliata ◽

Root Surface Area ◽

Citrus Paradisi ◽

Root Tips ◽

Volume Number ◽

Local Soil ◽

Volkamer Lemon ◽

Citrus Rootstock

Florida citrus has had an average annual on-tree-value of ≈1 billion dollars during the past decade in Florida. Nearly all of the 845,260 acres of citrus in Florida is produced on grafted trees consisting of a commercial scion cultivar and a rootstock selected specifically for local soil, environment, and pest pressures. With vastly different root-zone environments, ranging from deep sands to drained and cleared pine Flatwoods, a large number of different rootstocks are utilized. These rootstocks are started from seed at more than 100 commercial nurseries statewide, which currently produce an estimated 6 million trees a year. Although the optimum germination conditions, basic physiological performance, and adaptability of many rootstocks are known, there has been minimal investigation on early root development in seedling trays at the nursery. Four hundred seedlings of `Swingle' citrumelo (Citrus paradisi Macf. `Dunacn' × Poncirus trifoliata), `Smooth Flat Seville', `Volkamer' lemon (Citrus volkameriana), and `Sun Chu Sha' mandarin were seeded in a randomized block experimental design and grown at a commercial nursery. Seedling root systems (100/rootstock) were analyzed for a number of variables using the Rhizo (Regent Instruments, Inc.) software package and a dual light source scanner. Using the SAS general linear model procedure, hypothesis testing revealed rootstock selection had a significant effect on total root length, total root surface area, total root volume, number of root tips, number of root forks, root dry weight, and stem diameter. For most characteristics, rootstock genotype accounted for a greater portion of variability than samples (plant to plant variability).

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‘Ray Ruby’ Grapefruit Affected by Huanglongbing I. Planting Density and Soil Nutrient Management

HortScience ◽

10.21273/hortsci15111-20 ◽

2020 ◽

Vol 55 (9) ◽

pp. 1411-1419

Author(s):

Dinesh Phuyal ◽

Thiago Assis Rodrigues Nogueira ◽

Arun D. Jani ◽

Davie M. Kadyampakeni ◽

Kelly T. Morgan ◽

...

Keyword(s):

Citrus Sinensis ◽

Nutrient Management ◽

Soil Nutrient ◽

High Density ◽

Fruit Yield ◽

Poncirus Trifoliata ◽

Tree Planting ◽

Planting Density ◽

Citrus Paradisi ◽

Canopy Volume

Huanglongbing (HLB), or citrus greening disease, affects practically all fruit-bearing trees in commercial citrus orchards in Florida with no cure identified yet. High-density plantings and enhanced nutritional programs such as application of controlled-release fertilizer (CRF) with higher micronutrient levels can mitigate disease symptoms and extend the tree life span of sweet oranges (Citrus sinensis). The objective of this study was to evaluate the effects of tree planting density and application of CRF blends differing in N to K ratio and micronutrient content on grapefruit (Citrus paradisi) plant health, canopy volume, fruit yield, and fruit quality in an HLB-affected orchard. A study was conducted in Florida for two growing seasons (2017–18 and 2018–19) to evaluate the response of ‘Ray Ruby’ grapefruit on Kuharske citrange (Citrus sinensis × Poncirus trifoliata) to three planting densities (300, 440, and 975 trees per ha) and two CRF blends [12 nitrogen (N)–1.31 phosphorus (P)–7.47 potassium (K) and 16N–1.31P–16.6K] with different nutrient sources and composition. According to quantitative real-time polymerase chain reaction testing, all sampled trees tested positive for Candidatus Liberibacter asiaticus, the pathogen associated with HLB. Trees planted at 975 trees per ha had 33% lower canopy volume per tree but 160% greater fruit yield per hectare and 190% higher yield of solids compared with 300 trees per ha. Fruit produced in high-density planting (975 trees per ha) was 18% more acidic with higher soluble solid compared with low-density planting (300 trees per ha). The use of a CRF blend with higher amounts of micronutrients along with lower K increased canopy volume in both seasons and resulted in 24% and 29% reduction in fruit yield per hectare and yield of solids, respectively, in 2017–18. Our results indicate that high-density plantings increase fruit yield per area, and regardless of the N to K ratio, the use of CRF blends supplemented with micronutrients may not increase fruit yield in HLB-affected grapefruit.

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Rehabilitation of Huanglongbing-affected Citrus Trees Using Severe Pruning and Enhanced Foliar Nutritional Treatments

HortScience ◽

10.21273/hortsci11105-16 ◽

2017 ◽

Vol 52 (7) ◽

pp. 972-978 ◽

Cited By ~ 6

Author(s):

Robert E. Rouse ◽

Monica Ozores-Hampton ◽

Fritz M. Roka ◽

Pamela Roberts

Keyword(s):

Leaf Area ◽

Cost Effective ◽

Early Years ◽

Poncirus Trifoliata ◽

Juice Quality ◽

Foliar Nutrition ◽

Nutritional Treatment ◽

Fruit Crop ◽

Canopy Volume ◽

Citrus Trees

Citrus trees affected by huanglongbing (HLB) become diminished, weak, and develop dieback resulting in reduced production. Decline in fruit yield ultimately prevents economically acceptable commercial citrus production. The objectives of this study were to evaluate the effects of severe pruning in combination with an enhanced foliar nutritional treatment on growth, yield, and juice quality of HLB-affected orange trees. The bacterial titer within the trees was monitored before and after treatments, and a cost–benefit analysis provided an economic evaluation of the treatments. Fifteen-year-old ‘Valencia’ orange (Citrus sinensis Macf.) trees on Swingle citrumelo rootstocks [C. paradisi × Poncirus trifoliata (L.) Raf.] with 100% incidence of HLB, confirmed by real-time polymerase chain reaction (PCR), were severely pruned back to the main scaffold branches. Between 2010 and 2015, foliar nutrients were sprayed on both pruned and nonpruned trees to target new flush growth. Three enhanced nutritional foliar treatments were evaluated and compared with a control foliar nutritional treatment that was considered to be a standard practice before endemic HLB. The enhanced nutritional treatments included a mixture of micro- and macronutrients commonly known as the “Boyd cocktail,” a micronutrient package labeled Fortress © (Florida Phosphorus LLC, Key Largo, FL) sprayed with potassium nitrate (KNO3), and the Fortress © micronutrient package sprayed with urea. The experiment was a split-plot with seven replications, with pruning as the main plots, and a foliar nutritional treatment as subplots. Tree pruning was performed in Feb. 2010 before the spring flush. Pruned trees grew longer shoots than the controls the year after pruning. Canopy volume and leaf area were greater with nonpruned trees, but the chlorophyll content per cm2 leaf area was higher in the pruned trees compared with nonpruned trees in 3 years of the 5-year experiment. Pruned and nonpruned trees bloomed and set fruit the first year of the experiment in the spring of 2010–11. The fruit crop for the 2010–11 and 2014–15 seasons, and the overall total fruit crop for the 2010–15 season on pruned trees were significantly lower than those on nonpruned trees. However, no significant yield differences were found between pruned and nonpruned trees in the 2011–12, 2012–13, and 2013–14 growing seasons. Fruit yields from pruned trees never surpassed the yields from nonpruned trees, and this was possibly due to the severe-pruning treatment. Thus, severe pruning, as used in this trial, was not cost effective through the first 5 years after pruning. The rapid regrowth response of the pruned trees, however, may indicate that a reduced pruning approach could be effective at rejuvenating the HLB-affected trees, and an alternative to tree removal and replanting. Enhanced foliar nutrition treatments provided some yield benefits, especially in the early years of the trial. However, the enhanced foliar nutrition treatments did not prove to be cost effective.

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Effect of rhizobacteria strains on the induction of resistance in barley genotypes against Cochliobolus sativus

Hellenic Plant Protection Journal ◽

10.2478/hppj-2020-0009 ◽

2020 ◽

Vol 13 (2) ◽

pp. 83-92 ◽

Cited By ~ 1

Author(s):

A. Adam

Keyword(s):

Plant Growth ◽

Pseudomonas Putida ◽

Growth Parameters ◽

Disease Incidence ◽

Dry Weight ◽

Cochliobolus Sativus ◽

Resistance Level ◽

Wet Weight ◽

Number Of Leaves ◽

Barley Genotypes

SummaryEnhancement of the resistance level in plants by rhizobacteria has been proven in several pathosystems. This study investigated the ability of four rhizobacteria strains (Pseudomonas putida BTP1 and Bacillus subtilis Bs2500, Bs2504 and Bs2508) to promote the growth in three barley genotypes and protect them against Cochliobolus sativus. Our results demonstrated that all tested rhizobacteria strains had a protective effect on barley genotypes Arabi Abiad, Banteng and WI2291. However, P. putida BTP1 and B. subtilis Bs2508 strains were the most effective as they reduced disease incidence by 53 and 38% (mean effect), respectively. On the other hand, there were significant differences among the rhizobacteria-treated genotypes on plant growth parameters, such as wet weight, dry weight, plant height and number of leaves. Pseudomonas putida BTP1 strain was the most effective as it significantly increased plant growth by 15-32%. In addition, the susceptible genotypes Arabi Abiad and WI2291 were the most responsive to rhizobacteria. This means that these genotypes have a high potential for increase of their resistance against the pathogen and enhancement of plant growth after the application of rhizobacteria. Consequently, barley seed treatment with the tested rhizobacteria could be considered as an effective biocontrol method against C. sativus.

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THE EFFECT OF SALINITY OF IRRIGATION WATER AND SPRAYING BY HUMIC ACID IN SOME OF MORPHOLOGICAL, PHYSIOLOGICAL PROPERTIES, GROWTH AND YIELD OF WHEAT (Triticum aestivum L.)

Iraqi Journal of Desert Studies ◽

10.36531/ijds/20100101 ◽

2020 ◽

pp. 1-12

Author(s):

E. K. Al-Fahdawe ◽

A. A. Al-Sumaidaie ◽

Y. K. Al-Hadithy

Keyword(s):

Humic Acid ◽

Plant Height ◽

Irrigation Water ◽

Saline Water ◽

Block Design ◽

Nitrogen Concentration ◽

Dry Weight ◽

Growth And Yield ◽

Biological Yield ◽

Phosphorus And Potassium

A pots experiment was conducted at the Department of Biology/College of Education for Girls/University of Anbar during Autumn season of 2018-2019 to study the effect of the salinity irrigation water and spray by humic acid in some of morphological, physiological, growth and yield traits of wheat cv. IPa. The experiment was randomized complete block design (RCBD) with three replications. The first factor was assigned for irrigation by saline water at four level (S0, S1, S2 and S3), while the second factor was the foliar spraying of humic acid in three level (0.0, 1.0 and 1.5 g l-1). The results showed that there was significant reduction in plant height, vegetative dry weight, biological yield and chlorophyll leaves content when the plants were irrigated by saline water approached to 41.09 cm, 0.747 g, 0.849 g plant-1 and 38.67 SPAD, respectively at salinity level of 8.3 ds m-1 compared with the plants which irrigated by fresh water. The total carbohydrates were significantly decreased at the treatment of 8.3 ds m-1 reached 18.71 mg g-1. Spray levels humic acid achieved a significant increase in plant height, dry weight of the vegetative part, biological yield and chlorophyll leaves content sprayed at 1.0 and 1.5 g l-1 compared to no sprayed. Nitrogen concentration was significantly increased, while both phosphorus and potassium were decreased in the vegetative parts of wheat as the salinity of irrigation water increased. However, the increase of humic acid levels led to significant increasing in nitrogen, phosphorus and potassium concentration.

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