Iranian Journal of Soil Research
Year:2004 | Volume:18 | Issue:1|Papers Count:17

The effects of application of zinc sulfate by different methods and times on grain yield and protein content of chickpea was studied. An experiment was conducted in a completely randomized block design with a factorial arrangement of treatments (control=Zn0, soil application=Zns, foliar spray in early flowering = Znf1, foliar spray in early podding = Znf2 and their components as Zns Znf1-Zns Znf2-Znf1 Znf2-Zns Znf1 Znf2 two planting date: D1= fall and D2= spring) with three replications. Soil application of ZnSO4 was 20 kg/ha and in foliar application solution concentration was 0.2 percent. Results indicated that the effects of year, fertilizer treatments ,planting dates and their interactions on yield were significant (a=1%). The maximum yield was obtained in treatment of D1 ZnS Znf1 (soil application and one foliar spray of ZnSO4 in early flowering in fall planting) and treatment D1Zns (soil application of ZnSO4 in fall planting) with the yields of 1524 and 1522 kg/ha, respectively. Results indicated that application of zinc sulfate increased Zn uptake, grain yield and protein content by soil application at fall planting. It was also observed that in fall planting, an application of zinc sulphate in preplanting (20 kg/ha) and foliar spray in early flowering and in spring planting, and a foliar spray in early flowering could be recommended.

In order to test the effect of different constituents of Golden Biophosphate fertilizer (A combination of concentrated rock phosphate, sulfur, thiobacillus, and organic matter), an experiment was carried out using completely randomized design with twenty treatments. Each treatment included two apple trees with three replications in Torough Station of Agricultural Center of Khorasan on the apple trees during 2002. Treatments were: T1= control (without P use), T2= using P as triple superphosphate, T3= 40% concentrated RP + 40% sulfur + 16% cow manure (CM) + 4% zinc sulphate, T4 = T3 + 20 grams thiobacillus inoculant, T5= T3 + 40 grams thiobacillus inoculant, T6= T3 + tea residues instead of CM, T7 = T4 + tea residuse instead of CM, T8 = T5 + tea residues instead of CM, T9= T3 + compost instead of CM, T10 = T4 + compost instead of CM, T11 = T5 + compost instead of CM, T12 = 50% concentrated RP + 30% sulfur + 16% CM + 40% zinc sulfate, T13= T12 + 20 grams thiobacillus inoculant, T14 = T12 + 40 grams thiobacillus inoculant, T15 = T12 + tea residues instead of CM, T16= T13 + tea residues instead of CM, T17 = T14 + tea residues instead of CM, T18=T12 + use of compost instead of CM, T19= T13 + use of compost instead of CM, and T20 = T14 + use of compost instead of tea residues. In all treatments mentioned, 1 kg of each fertilizer was applied to each tree at 40 cm depth, by deep placement method. The results indicated that there were significant differences between available P concentration in deep placement method and P levels of leaves in treatments which included concentrated RP + sulfur, thiobacillus bacteria and CM, compared with control treatment and treatments with no thiobacillus. Based on the results, it seems that (P<5%), Golden Biophosphate can be used at the rate of 1 kg/tree in apple orchards, instead of triple superphosphate fertilizer.

Quantity-intensity (Q/I) curves and their parameters are among the methods of determining soil K status. The objectives of this work were to study the correlation of Q/I parameters with K extracted by chemical methods and garlic (Allium aestivum) indicies in 8 soils from Hamadan Province. Soil samples were equilibrated with solution containing different potassium activity ratios. Changes in K concentration in the equilibrium solution were plotted against activity ratio of K, and Q/I parameters were determined. Available K was determined by 13 chemical extractants. The results showed variations in soils with respect to Q/I parameters. Activity ratio at equilibrium (ARk) was significantly correlated with K extracted by 0.1 M BaCl2, 0.05 and 0.1 M HCl, 1 M sodium acetate, 0.025 M H2 SO4, and distilled water. Labile K (ΔK) was significantly correlated with K extracted by 0.1 M BaCl2, citric acid + stroncium chloride, Mehlich 1, 0.05 and 0.1 M HCl, 1 M sodium acetate, 0.025 H2SO4 and distilled water. Labile K was significantly correlated with ARk . Slowly exchangeable K was significantly correlated with K extracted by DTPA and NH4OAC. Potassium buffering capacity was significantly correlated with CEC. The results of pot experiment showed that KΔ was significantly correlated with K concentration, relative yield and response and ARk were significantly correlated with K concentration, K uptake, relative yield and plant response. Other Q/I parameters were not significantly correlated with plant indicies. Labile K and ARk critical levels for 90 percent relative yield of garlic were 65 mg kg-1 and 10 (mmol L-1)0.5, respectively.

In order to study the effects of urea foliar spraying at different growth stages on Sabalan dryland wheat grain yield and protein concentration, experiments were conducted and set up in RCBD with 6 tretments and 3 replications during 1998-2001. The study was conducted at Maragheh Dryland Agricultural Research Station. Treatments included: control (no sprayings), spraying of a 5% urea solution (20 kgN.ha-11) at tillering, shooting, flag leaf and pollination stages, and urea foliar spraying (5%) with 2 l.ha-1 2.4.D herbicide at tillering stage. The same nitrogen fertilizer rate (50 kgN.ha-1) was placed in soil for all treatments at planting time. The results showed that the effects of urea foliar spraying differed significantly on wheat grain protein concentration. The highest grain protein concentration (21.1%) was obtained from urea foliar spraying at shooting stage. Urea foliar spraying at flag leaf stage not only increased grain protein concentration (18.2%), but also increased grain yield (24%) compared to control treatment. It can be concluded that urea foliar spraying at different growth stages can affect differently the grain protein concentration, protein and grain yields in dryland wheat. The recommended time for urea foliar spraying is flag leaf stage, which can increase grain protein concentration, protein and grain yields compared to other growth stages.

A completely randomized factorial block experiment with three replications was carried out during 2001 at Khoy Agr. Research Station to evaluate the main and interactive effects of potassium and magnesium on the yield and quality of Golshid variety of sunflower. Due considerations were given to the antagonistic effects between these two nutrients in the context of determining the optimum levels of fertilizer application for the best yield. The treatments included four levels of potassium (K0=0, K1=45, K2=90 and K3=135 kg K2O as potassium sulfate per hectare) and four levels of magnesium sulfate ((Mg0=0, Mg1=50, Mg2=100 and Mg3=150 kg MgSO4/ha). The results showed that seed yield increased with increasing levels of potassium up to the rate of K3=1.5 times the SWRI’s recommended rate combined with magnesium sulfate up to 100 kg/ha yielded the best with no significant increases at higher rates. The best rate for magnesium sulfate turned out to be 50kg/ha. Application of potassium and magnesium increased the thousand kernel weight but no effect was seen on the plant height or the diameter of the plant stem. The diameter of the sunflower disc improved with the application of potassium and magnesium but the effect was not significant. There were no significant interactive effects between potassium and magnesium levels. However, the best seed yield was obtained with K2Mg1 and the best disc diameter and the thousand kernel weight were obtained with K3Mg2. Finally, the best ratio for the rates of potassium to magnesium was determined to be about 3 to 1.

Sugar beet (Beta vulgaris L), after germination and establishment in the soil, can tolerate relatively high levels of salinity. Due to the difference in plants responses to ammonium and nitrate-N under saline and non-saline conditions, and considering the necessity of using the best nitrogen form to achieve the maximum sucroce content and sucrose yield, a pot experiment was carried out on the effect of nitrogen forms on sucrose content of two lines of sugar beets with different salt tolerance. The results showed that with increasing level of irrigation water salinity, nitrate-N in comparison to ammonium-N yielded more roots and shoots in both salt sensitive (22939-196) and salt tolerant (7233-p.29 X Mst) lines. Futhermore, the results showed that salt stress generally increases the proline content of leaf in both lines of sugar beet. The amount of proline in salt-tolerant line was higher than salt-sensitive line. Accumulation of proline under salt stress was more significant in nitrate-N than ammonium-N. The results of chemical analysis of root tissues indicated that there was not any significant difference between the effects of the two nitrogen forms on the percentage of sucrose, extractable sugar and sugar molasses content of the root. The amount of impurity content of roots increased with increasing levels of irrigation water salinity, and when nitrate-N was used instead of ammonium- N.

The effects of four irrigation scheduling schemes on the yield and water use efficiency (WUE) of wheat were investigated. A two-year field experiment was carried out in Golpaygan during 1997-1999 growing seasons. The experimental design was randomized complete block, with four replications and four treatments. The treatments were irrigation after 50 (T1), 75 (T2), 100 (T3), and 125 (T4) mm of cumulative evaporation from Class A evaporation pan. Water depth was calculated based on increasing the root zone moisture to field capacity. The effect of year on seed and straw yields, protein content, and WUE was highly significant. The yields and WUE were higher in the first year, but protein content was higher in the second year. The effect of irrigation on seed and straw yields, protein content, and WUE was significant. The highest seed and straw yields were obtained from T2 (7825 and 13625 kg/ha, respectively). The highest protein content was obtained from T2, which was significantly higher than T3. WUE of T2 was significantly higher than T1. The lowest and the highest WUE were obtained from T1 (0.99 kg seed/m3) and T4 (1.24 kg seed/m3), respectively. Under present experimental condition, T2 treatment (75 mm cumulative evaporation) with total 642 mm of water, 9 irrigations, and 7825 kg/ha of grain yield and 13625 kg/ha of straw yield, was the best treatment. In this treatment, without considering the rainfall WUE was 1.22 and 2.11 kg/m3 for seed and straw, respectively.

In order to investigate the yield and water use efficiency (WUE) of forage millet under 8 irrigation regimes, a two year field experiment was conducted in 2000 and 2001 growing seasons at Ardakan Agricultural Station, Yazd. Accumulative pan evaporation (APE) was measured in order to determine the time of irrigation. The treatments I1, I2, I3 and I5 were irrigated when APE reached 90, 120, 150 and 180 mm, respectively; I5 and I6 were irrigated when APE reached 150 and 180 mm till the first cut respectively, and afterwards like I2 treatment; I7 and I8 were irrigated when APE reached 120 mm from establishment to first cut and then irrigated when APE reached 150 and 180 mm, respectively. The treatment effects were significant in the year 2001. On the average, treatment I4 with 9.2 kg/m3 and I1 with 6.8 kg/m3 had the highest and the lowest WUE, respectively. The fresh and dry yields of treatment I5 were respectively 24.9 and 6.6 ton/ha in the year 2000; and 18.2 and 4.5 ton/ha in the year 2001. On the average WUE of treatment I5 was 8.9 kg/m3.

Proper irrigation management by optimizing the time and quantity of water application plays an important role in determining fruit yield and quality of grape. The present study was conducted to find out the best irrigation scheduling for Peykani grape. The main objectives were to improve yield and quality of this crop. A field experiment was carried out using six irrigation treatments designed based on different phenological stages of grape in 4 replications. This experiment.was conducted using Randomized Complete Block Design in Kashmar region during 1997-2000. Grapes were harvested when the amount of soluble solids reached a value of 20-21. Then physical tests were run including yield, length and weight of grape. Chemical tests were conducted to measure the soluble solids, titrable acid, percent moisture and pH of grape. The results showed that different irrigation schedules had a significant effect on fruit yield and quality. Maximum yield recorded (30.1 t/ha) was obtained from the following treatment: one irrigation at winter followed by another one before blooming, the next irrigation was on 23rd of May after flowering; followed by 20 day interval irrigation periods, applied untill harvest. The effect of irrigation treatments had a significant effect on physical and chemical tests at =5% and the maximum amount of length, weight and soluble solids were obtained from the treatment mentioned above.

About 7200 ha of farm lands in Qom Province is cultivated to alfalfa, and about 60 percent of the lands have salinity problems. Therefore, it is neccessary to indentify the most salt tolerant alfalfa cultivars for higher forage production under these conditions. Consequently, an experiment was carried out with five alfalfa cultivars (Hamadani, Yazdi, Bami, Rahnani and Seriver) and three replications in three farms in Qomrood area with water salinities of 5, 7 and 10.5 dS/m, and soil surface salinities of 7.4, 9.2 and 13.4 dS/m. The experimental design was RCBD. Due to high salinity of soil and water in the third farm, none of the alfalfa cultivars germinated . The results showed that there were significant differences between alfalfa cultivars in the yield and quality of forage and morphological characteristices. Also, the results of combined analysis showed that the effect of year was significant. In Kashipoor Farm maximum average yield of fresh forage and dry matter were, respectively, 57.8 and 17.1 t/ha in 1999. In Abedini Farm, the maximum fresh yields were 44.2 and 43.1 for 1999 and 2000, respectively. Among alfalfa cultivars, Yazdi and Hamadani cultivars were the superior cultivars, and produced the highest fresh and dry forage yields at both farms. Therefor they can be recommended as suitable cultivars for Qom Province.

The effect of salinity stress on the cuttings of three commercial cultivars of pomegranate (Alak-torsh, Malas-torsh and Malas-shirin) was studied for determination of their salinity tolerance. After rooting of the cuttings, they were planted in the plastic pots that contained 1:1 ratio of sand and perlite, and were irrigated with complete Hoaglands solution immediately. After three weeks, the plants were treated with different concentrations (0, 40, 80 and 120 meq/lit) of sodium chloride solution. These treatments continued during 80 days with irrigation water. Finally, uptake and transport of ions (Na, K, Ca, Mg, N and Cl) and soluble sugars were measured in the three cultivars. With increasing sodium chloride concentration in irrigation water, the amount of Na, Cl and K in the tissues increased but amount of Ca, Mg and N of the tissues decreased and differences among up-taking and transporting of ions in three cultivars were not significant. With increasing sodium chloride concentrations in irrigation water, the amount of soluble sugars decreased. The results showed that pomegranate accumulated Na in root cells up to 40 meq/lit NaCl and without transporting it to the aerial parts. Nevertheless, at higher levels of salinity, due to the saturation of root cells with Na, transportation of Na occurred from root to aerial parts.

The study area is about 75000 hectares and is located in Qom-Masileh area, Qom Province of Iran. It is located between 34° 30¢ to 34° 52¢ north latitude and 50° 47¢ to 51° 19¢ east longitude. Based on the data of the nearest synoptic station to the study area (Qom Station), the climatic type of the area is desertic. The maximum air temperature is 34.5 °C in June and the minimum air temperature is 3.6 °C in December. The annual rainfall is about 145 mm. The objective of this research was to elaborate an approach for the prediction of the land production potential for irrigated cotton taking into account the environmental condition in the study area. The methodology considers different hierarchically ordered production situations. In the first hierarchical production situation, the radiation thermal potential (RPP), or the potential yield of irrigated cotton, was calculated. In the second hierarchical production situation, land production potential (LPP) for phases of family has been calculated considering soil indicies. The result of the first hierarchical production situation showed that irrigated potential yield based on FAO crop growth model for cotton (lint plus seed) was 6460 kg/ha and cotton lint was 2308 kg/ha in the study area. The result of the second hierarchically ordered production potential situation showed land production potential for irrigated cotton (lint plus seed) 65 to 5623 kg/ha and cotton lint 23 to 1968 kg/ha due to lime, gypsum, gravel, soil depth, salinity and alkalinity limitations.