Using different methods to determine critical level of potassium for wheat plant (triticum durum)‎ in Erbil plain soils

Other Title(s)

اسخدام طرق مختلفة لإيجاد الحد الحرِج للبوتاسيوم في ترب سهل أربيل لنبات الحنطة (Triticum durum)‎

Dissertant

Hama Amin, Chra Uthman

Thesis advisor

Ismail, Akram Uthman

University

Salahaddin University-Hawler

Faculty

Agriculture College

University Country

Iraq

Degree

Master

Degree Date

2012

English Abstract

The pot experiment was conducted from 11th, December, 2010 to 2nd, June, 2011 at the experiments farm of College of Agriculture, University of Salahaddin at Girdarasha (3.5 Km) south of Erbil city with the GPS reading (N 36 7.385, E44 1.315) it is a part of Erbil plain, (414 m above sea level).

In order to study the critical level of potassium in Erbil plain soils according to fertilization concepts which depend on chemical and physicochemical bases, 23 superficial soil samples (0-0.3m) have been chosen which differ in chemical and physical properties, and a series of laboratory and field experiments have been done for it.

Potassium forms (soluble, exchangeable, non-exchangeable, mineral and total potassium) for the soils have been estimated according to Beckett (1964) method to identify the thermodynamic equilibrium between potassium in liquid and solid phase (Q / I) to obtain the thermodynamic parameters which are related to the potassium fertilization state.

Wheat seeds (Triticum durum, L.

variety.

Acsad.65) have been planted in plastic pots of 7 kg capacity and added to it four levels of potassium (0, 20, 40 and 60 mg K+ kg-1) as Muriate (KCl) as a source of potassium which contain 52% of potassium.

Also 22.5 mg kg-1 nitrogen as urea and 22.5 mg kg-1 phosphorus as triple super phosphate have been added to the soil.

The main results can be summarized as follow : 1.

The ranges of different forms of potassium in the studied soils were as follow, soluble, exchangeable, non-exchangeable, mineral and total potassium were 0.042 to 0.495 mmol.L-1, 3.71 to 14.45, 3.74 to 51.68, 70.05 to 566.23 and 79.23 to 630.19 mmol Kg-1 respectively.

2.

The values of thermodynamic parameter ranges for equilibrium activity ratio of potassium ARke, the free energy (ΔG) and potential buffering capacity of potassium (PBCke) were 0.0016 to 0.0139 (molL-1)0.5, -3814 to - 2534 cal mol-1 and 40.56 to 96.01 cmolc Kg-1 (mol L-1)0.5 respectively.

3.

The application of potassium levels affected significantly on grain yield, where the highest yield was recorded from the fourth treatment (60mg K+ kg-1 soil) which ranged from 21.46 to 34.69g pot-1 with a mean of 26.45 g pot-1, while the lowest value was recorded from control treatment (K0) and ranged between 13.81 and 23.5 g pot-1 with a mean of 18.29 g pot-1.

The soil location had a significant effect (p≤ 0.01) on grain yield, where the highest value 29.94g pot-1 was recorded from soil number (2), while the lowest value 18.20 g pot-1 was recorded from soil number (20).

4.

The interaction between levels of potassium and soil locations have affected significantly (p≤ 0.01) on grain yield of wheat, the highest value (34.69 g pot-1) was recorded from treatment combination (S2K60), while the lowest value (13.81 g pot-1) was recorded from the treatment combination (S20K0).

5.

The levels of applied potassium affected significantly on dry matter, the highest value was recorded from the fourth treatment (60 mg K+ kg-1 soil) which ranged from 24.70 to 42.25g pot-1 with a mean of 30.82 g pot-1, while the lowest value was recorded from control treatment (K0) and ranged between 15.36 and 26.06 g pot-1 with a mean of 21.39 g pot-1.

6.

The application of levels potassium affected significantly on the protein content in the grain yield, the highest value was 20.06 g 100 g-1, while the lowest values was 13.12 g 100 g-1.

7.

The soil location were affected significantly (p ≤ 0.01) on the protein content in the grain yield, the highest value 17.96 g 100 g-1 was recorded from soil number (4), and the lowest value 14.51 g 100 g-1 was recorded from soil number (20).

8.

The interaction between levels of potassium and soil locations was affected significantly (p ≤ 0.01) on the protein content in the grain yield, the highest value 20.06 g 100 g-1 was recorded from combination (S2K60), while the owes value 13.12 g 100 g-1 was recorded from the treatment combination (S20K0).

9.

The critical levels of soil potassium depending on soluble potassium concentration, exchangeable potassium, potassium activity, potassium activity ratio (ARk), potassium activity ratio at equilibrium ARke, the supplying power (-ΔG) and potential buffering capacity of potassium (PBCke) were 0.165 (mmol L-1), 7.8 (mmol Kg-1), 0.000135 (mol L-1), 0.00336 (molL-1)0.5, 0.0065 (mol L-1)0.5, -2883 (cal mol-1) and 77.12 cmolc Kg-1 (mol L-1)0.5 respectively.

10.

The critical levels of soil potassium depending on soluble potassium, exchangeable potassium, potassium activity, potassium activity ratio (ARk), potassium activity ratio at equilibrium ARke, the free energy (-ΔG) and potential buffering capacity of potassium (PBCek) using norm treatments were 0.118 (mmol L-1), 7.06 (mmol kg-1), 0.00011 (mol L-1), 0.00309 (mol L-1)0.5, 0.0023 (mol L-1)0.5, -3598.8 (cal mol-1) and 52.49 cmolc Kg-1(mol L-1) 0.5 respectively.

11.

The potassium critical level in wheat plant depending on potassium concentration in dry matter and uptake were 1.65 g 100 g-1 and 0.49 g pot-1 respectively.

12.

The potassium critical level in wheat plant depending on potassium concentration in dry matter and uptake by using norm treatments were 1.4 g 100 g-1 and 0.

39 g pot-1 respectively.

13.

The coefficient of determination values between potassium critical level depending on the studied parameters and wheat relative yield depending on norm treatments were higher compared with using mean of yield.

Main Subjects

Botany

Topics

• Iraq
• Irbil
• Wheat

No. of Pages

112

Table of Contents

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-314374