Effect of Vermicompost Fertilizer on Quantitative Characteristics of Potato

Abstract

Effect of Vermicompost Fertilizer on Quantitative Characteristics of Potato
 
S. H. Mahmoodi Nezhad Dezfully1*,G. Soltani Kazami2, A. Saadi Alkasir3
1-Soil & Water Research Department, Research Assistant Professor  of Safiabad Agricultural & Natural Resources  Research and Education Center, AREEO, Iran
2-Ph. D of Agroechology,  Jahad Agricultural organization of Khuzestan
3- M.Sc of  Agronomy, Jahad Agricultural organization of Gotvand
 
 
*Corresponding auther email: shmn178@yahoo.com
 
               Received:  4 April 2017                                                                                   Accepted: 24 June 20017
 
Abstract
To evaluate the effect of vermicompost fertilizer on quantitative characteristics of potato in north of Khuzestan region, in 2016-17 an experiment was carried out based on randomized complete block design with 3 replications and 3 treatments: vermicompost, (cow + sheep manure), and chicken manure. Results showed that fertilizer treatments had significant effect on large size tubers yield and large size tubers number at 1% probability level and on medium size tubers yield, total tubers yield, medium size tubers number, total number of tubers and tubers nitrate percentage at 5% probability level. Based on the results obtained, the most effective treatments on total yield of potato were vermicompost cow+ sheep manure, and chicken manure, respectively. The total yield of potato by application of vermicompost was 1.3% more than the yield by application of cow +sheep manure and 20.6% more than the yield by application of chicken manure. The results showed that application of vermicompost was not only economic and effective on potato yield, but also was better than other treatments for human health and environmental pollution.                                                                                                   
 
Keywords:Chicken manure, Vermicompost, Manure, Potato
 

Keywords


       
   

                 Research on Crop Ecophysiology                                  Vol.12/2, Issue 2 (2017), Pages: 82 -  96

 

 

 
 

Original Research

 
 

 

 


Effect of Vermicompost Fertilizer on Quantitative Characteristics of Potato

 

S. H. Mahmoodi Nezhad Dezfully1*,G. Soltani Kazami2, A. Saadi Alkasir3

1-Soil & Water Research Department, Research Assistant Professor  of Safiabad Agricultural & Natural Resources  Research and Education Center, AREEO, Iran

2-Ph. D of Agroechology,  Jahad Agricultural organization of Khuzestan

3- M.Sc of  Agronomy, Jahad Agricultural organization of Gotvand

 

 

*Corresponding auther email: shmn178@yahoo.com

 

               Received:  4 April 2017                                                                                   Accepted: 24 June 20017

 

Abstract

To evaluate the effect of vermicompost fertilizer on quantitative characteristics of potato in north of Khuzestan region, in 2016-17 an experiment was carried out based on randomized complete block design with 3 replications and 3 treatments: vermicompost, (cow + sheep manure), and chicken manure. Results showed that fertilizer treatments had significant effect on large size tubers yield and large size tubers number at 1% probability level and on medium size tubers yield, total tubers yield, medium size tubers number, total number of tubers and tubers nitrate percentage at 5% probability level. Based on the results obtained, the most effective treatments on total yield of potato were vermicompost cow+ sheep manure, and chicken manure, respectively. The total yield of potato by application of vermicompost was 1.3% more than the yield by application of cow +sheep manure and 20.6% more than the yield by application of chicken manure. The results showed that application of vermicompost was not only economic and effective on potato yield, but also was better than other treatments for human health and environmental pollution.                                                                                                   

 

Keywords:Chicken manure, Vermicompost, Manure, Potato

 

INTRODUCTION

 

Potato (Solanum tuberosum L.)  is a one-year-old plant from the Solanaceae which is an autotetraploid strain with 48 chromosomes. This plant is cultivated in most parts of the world and in the latitude of 60 degrees north to 40 degrees south and elevation up to 3500 meters above sea level. Potato is a tuberous crop that plays an important role as one of the most important sources of nutrition for the people of the world. Potato production in 2012 was around 321 million tons of tubers from 19.6 million hectares of agricultural land. The nutritional value of potatoes is due to its high energy content. In addition, potatoes are important in human nutrition in terms of protein balance, containing essential amino acids, vitamins and minerals, so that with regard to the volume of production among the various agricultural products in the world, it is in the fourth place after wheat, rice and corn. (Malakouty, 1991).

The soils of the arid and semi-arid regions of Iran, which are more than 80% of the agricultural lands, are poor in organic matter. Addition of organic matter to the soil in order to increase the fertility of agricultural soils is essential.  However, limited traditional sources of organic matter, such as animal fertilizer, do not meet the increasing need of agricultural sector for organic matter (Baibordi, 2000). The abundant use of chemical inputs in vegetable production farms and greenhouses, and the rapid distribution of these products to the market , regardless of the time it takes to reduce the concentration or decomposition of harmful chemicals present in them, demonstrates the need to expand the organic production of these products (Gaskell, 1999). Vermicompost fertilizer is a certain type of earthworms that have the potential, to convert various types of extra organic matter (which often disturb and pollute the environment) into excellent quality organic fertilizer (Samawat, 2001). In nature, it takes 500 to 1000 years for to forma 5.2 cm layer of humus on the surface of the soil, but the worms reduce this time to a minimum of 5 years, (Samawat and Malakouty, 2003). Vermicompost is rich in humic substances and nutrients in a form that can be absorbed by the plants and has a variety of vitamins, growth-promoting hormones and different enzymes (Samawat, 2001).Increasing moisture holding capacity in the soil, improving the physical structure of the soil, reducing of soil erosion and accelerating the mineralization of nutrients without any restrictions for the plant growth are the advantages of using vermicompost fertilizers (Samawat and Malakouty, 2003). Lalande et al. (2000) stated that the use of fertilizer in soil is essential for increasing the stability of aggregates and also the fertility of agricultural lands, and by that, in addition to reducing the additional waste removal costs, the productivity of waste products also increases.

Haji Aghaei Kamrani et al. (2012) evaluated the effect of different culture media on the number of mini-tubers and the concentration of elements in the potato aerial part and roots. They showed that the highest concentrations of N, P and K were in the aerial parts and roots, in the treatments of 40% perlite + 30% soil + 30% vermicompost and 40% perlite + 30% soil + 30% compost. Alam et al. (2007) investigated the effect of vermicompost and fertilizer on growth and yield components of potatoes and reported that adding vermicompost + nitrogen, potassium, phosphorus and sulfur fertilizers had a significant effect on potato growth and yield. Ajudan Zadeh et al. (2005) showed that with increasing of organic matter up to 20 tons per hectare, potato yield increased. This indicates the importance of using organic fertilizers in increasing potato tuber yield and also the sensitivity of this plant to improvements of the physical properties of the soil. In 2003, Marjovi studied the levels of 0, 25 and 50 tons per hectare of urban compost on sugar beet and wheat yield and stated that there was no significant effect between the different levels of compost application in the first year with the control. However, in the second year, due to ease of access to the elements in compost manure as a result of the activity of soil organisms, there was a significant difference between treatment of 50 tons per hectare with control. The results of research conducted at the US Department of Agriculture showed that providing of nitrogen from compost manure for plants is less than nitrogen fertilizers, so that in most cases, about 25% of nitrogen, 6-15% of phosphorus and 30-60% of  potassium in the compost are released in the first year and 10% of it is released every year (Sikora and Szmidt, 2001).This is because, contrary to chemical fertilizers, available nitrogen in compost fertilizers appears in the course of composting as bonds with other carbon-specific elements (Sikora and Szmidz, 2001). Atiyeh et al. (2001) showed in their research that with the addition of pig vermicompost to the culture media of parsley and tomato, the growth of buds was increased. In a study conducted by Ferguson (2001), using of 20 tons per hectare of urban waste compost in vegetable fields increased the yield by 15 percent. Feibert et al. (1995) found that the consumption of 15 tons per hectare of compost increased the onion yield by 15 percent. The researchers stated that the reason of yield increase was due to improved nutrition elements, increased permeability and aeration in the soil, and increased microbial activity in the rhizosphere. In a study conducted by Wong and Chu (1985), with increasing the duration of composting and, consequently, reducing the ratio of carbon to nitrogen, the effect of created toxicity due to the reduction of organic acids in compost was reduced to a minimum or stopped. In a study conducted by Arancon et al. (2004), the increase in the leaf area of strawberries in the presence of vermicompost was stated as the result of an increase in the microbial population in the soil containing vermicompost. Mcginnis et al. (2003) stated the reasons for the increase in leaf area of basil (Ocimum basilicum L.) in the presence of vermicompost were the improvement of the physical properties of the environment, increasing the activity of microorganisms and increasing water holding capacity in the soil. Subler et al. (1998) mixed 10% and 20% vermicompost with soil and reported the improvement in the growth and germination of Petunia hybrida L., Calendula officinalis L., Capsicum annum L., Brassica oleracea and Lycopersicum esculentum L.

Since potato cultivation is common in many parts of Iran as an important and high-yielding crop (Talebzadeh, 2004), and also due to the special capacity of the North Khuzestan in the production of vermicompost, poultry manure and animal manure (due to the existence of poultry farms, animal husbandry and producers of vermicompost in the region), a research on the effect of different organic fertilizers on potato yield was carried out in this region.

 

Table 1. The results of soil and fertilizer analysis

K2O(tot)%

 

P2O5(tot) %

OC (%)

 

pH

ECe dS.m-1

 

Samples

 
 

480(ppm)*

14(ppm)*

0.50

8.11

3

Soil

 

1.1

2.2

18.3

7.93

11.3

Vermicompost

 

0.41

10.3

28.08

8.77

6(10%)

Poultry manure

 

0.74

1.1

37.2

8.56

16.9(10%)

Animal manure

 

 

 

 

 

 

 

 

* In soil samples, the amount of  P2O5 (tot) and K2O (tot) were reported in ppm

 

Materials and methods

 

In order to evaluate the effect of vermicompost on potato yield, a research in a randomized complete block design with 3 treatments and 3 replications was conducted in Khuzestan region in (2015-2016). Treatments included: 1) application of 4 tons per hectare of poultry manure; 2) application of 25 tons per hectare of animal cow and sheep manure; and 3) application of 3 tons per hectare of vermicompost.treatments 1,2 and 3topdressed with 600,465 and 600g/ plot urea in 3 splits.also,115g zinc solfate. 90 g manganese sulfate, 60 g cooper sulfate, and 20 g iron sequestering were applied to all treatments The project layout is shown in Table (1). In this experiment, the intervals between the bushes in each row were 25 cm, the intervals between the rows were 75 cm in each plot, the length of the rows in each plot was 6 meters and in each plot had 5 rows. It should be noted that the distance between the plots in each replication was 1 meter, the distance between replications was 2 meters and the planting depth was 15 cm. In all treatments, the amount of applied chemical fertilizer was calculated based on soil test, fertilizer analysis and fertilizer requirements of the crop and then uniformly distributed on the plots (Table 1) Small (less than 75g), medium (75 -250g) and large(more than 250 g) tubers yields and also numbers, percentage of dry matter and nitrate content of tubers were determined from the three central rows of each plot. Data analysis was performed using MSTAT-C statistical software and treatments means were compared by Duncan's test.


 RESULTS AND DISCUSSION

 

The results of chemical analysis of soil samples, vermicompost, poultry and animal manure used in the project are presented in (Table 1). The soil was not limited in terms of phosphorus, potassium and salinity, but, had limitation in terms of organic carbon content and alkalinity. Poultry manure are very rich in phosphorus content (Salardini, 1987), and as mentioned in Table (1), the highest percentage of P2O5 was related to poultry manure treatment the highest percentage of K2O was related to vermicompost treatment. According to (Table 1). Vermicompost, poultry and animal manure contain high organic carbon percentage and high nutritional values.

 

Tuber yield and number of tubers (small, medium, large and total)

Fertilizer treatments had no significant effect on yield and number of small size tubers (Table 2). Mean comparisons show that the highest small size tubers yield (6.05 t/ha) belonged to poultry manure treatment and the highest small size tubers number (21.39 tubers m-2) belonged to animal manure treatment (Table 3). Fertilizer treatments had a significant (p<0.05) effect on yield and number of medium size tubers. The results of mean comparisons Table 3 showed that the highest medium size tubers yield (36.56 t/ha) belonged to vermicompost treatment and the lowest yield (24.95 t/ha) belonged to poultry manure treatment. It should be noted that with respect to this trait animal and poultry manures were not statistically different. According to Table 3, the application of vermicompost in comparison to animal and poultry manures resulted in 22.3% and 31.7% increase in the medium size tubers yield, respectively. The highest medium size tubers number (24.60 tubers m-2) belonged to vermicompost treatment and the least number (17.69 tubers m-2) belonged to poultry manure treatment. Fertilizer effects treatments on yield and number of large size tubers were significant at probability (Table 2) 1% level. The highest yield and number of large size tubers belonged to animal manure, treatment and the treatments of poultry and vermicompost had statistically the same number and yield for large size tubers (Table 3). Fertilizer treatments had a significant (p<0.05) effect on total tubers yield and total number of tubers the highest total tubers yield (46.55 t/ha) belonged to vermicompost treatment and the highest total number of tubers (46.68 tubers m-2) belonged to animal manure treatment. There was no significant differences between the other two treatments with respect to total number and yield of tubers (Table 3). The results showed that main factor affecting yield (with the use of animal manure) was the significant increase in the number of large size tubers, which led to an increase in the large size tubers yield and thus the total tubers yield. Yazdan Dost Hamedani, (2003), reported that absorption of high nitrogen levels led to the production of large size tubers in potato. Animal manure modifies the physical properties of the soil and, as a result, increases the production of the crop, and by decomposing organic matter by microorganisms and producing carbon dioxide leads to an increase in photosynthesis, growth and yield of the plants. Animal manure can improve bulk density and water holding in the soil (Theodore and Jackson, 1999). The increase in large size tubers number indicates either an increase in temperature or availability of nitrogen (Rezaii and Soltani, 1996). Due to the uniformity of the temperature conditions in all treatments, the reason for the increase of the large size tubers number was the high nitrogen content in the animal manure which is confirmed by nitrates of tubers (Table 5). Rashidi et al. (2014) showed that the highest percentage of sugar and nitrogen in the potato tuber is due to the use of animal fertilizer. nitrogen excess stimulates vegetative growth, laceration in the tuber sprouting, and crop ripeness, as well as a decrease in the specific weight of the tuber (Mobli et al. 2009). Delay in the tuber sprouting and ripeness of the crop will cause the farmer to lose his first crop, which usually has a higher price, and consequently suffer financially. The reduction in the specific weight of the tubers also reduces the quality of their storage. Mobli et al. (2009) Stated that among crops, potato show the best response to animal fertilizers. The researchers have stated that although macro and micro elements consumed with animal manure are involved in soil fertility, the improvement of the physical structure of the soil is of more importance and, with the use of animal manure, the impact of nitrogen-containing fertilizers can increase by 20%.

 The main factor in increasing the total tubers yield with the application of vermicompost  was the increase in the number ofmedium size tubers, which increased the medium size tubers yield and ultimately the total tubers yield. Increasing vermicompost by improving the physical conditions and vital processes of the soil will make the nutrients such as nitrogen, phosphorus and potassium, and plant growth promoters and vitamins (vitamin B12) more accessible to the plants, which will increase the number of tubers and yield of the plant (Manghesh et al. 2015).  Arankon et al. 2003 showd that vermicompost can increase the growth and yield of crops by increasing the absorption of nutrients, especially nitrogen, by the plant. Atiyeh et al. (2001) showed   that the use of vermicompost, in addition to increasing the number of tubers, increases the number of main stems as well as the number of secondary stems in potato.  Vermicompost superiority on potato yield over other treatments, is the presence of nutrient elements of nitrate, phosphate, calcium and potassium in suitable form for the plant (Orosko et al. 1996). The application of vermicompost makes the plant to use more environmental factors during the growth period and thus obtain optimal conditions for the photosynthesis process (Jayanthi et al. 2002). The use of vermicompost can also increase the activity of microorganisms in the soil, which increases the amount of nutrients and nitrogen release from an organic form to the mineral form in the soil which finally leads to increases of the yield. Alam et al. (2007) reported the effect of vermicompost and chemical fertilizers on growth and yield components of potato. Adding vermicompost and nitrogen fertilizers, potassium, phosphorus and sulfur had a significant effect on potato growth and yield. The worms waste in vermicompost fertilizers often contain 5-11 times more nitrogen, phosphorus and potassium in the soil, which results in increase of fertility and consequently, yield increase (Samawat and Malakouty. 2003).  Alam et al. (2007), found that the use of 10 tons per hectare of vermicompost along with chemical fertilizer is required to increase potato tuber yield. It should be noted that medium potato tubers in Iran are more popular in the market, and in this study the use of vermicompost increased the medium size tubers yield in comparison to animal fertilizers (Table 3). One of the reasons for the popularity of the medium tubers is that the nitrate content of large potatoes is usually more than the medium tubers, and it is recommended to use medium potatoes in order to maintain health (Salamat Journal, 2014).

It is important to note that since animal manure and vermicompost have been able to increase one of the quantitative characteristics of the potato tuber, thus a mixture of these organic matter can give the best outcome in increasing the quantitative characteristics of the potato tubers.  In a research conducted in Peru, with chemical fertilizers and the fodder gathered from pig breeding sites, it’s been shown that the composition of these materials significantly increased different elements such as copper and zinc compared to chemical fertilizers in the dry matter of potato tubers (Srek et al. 2010).

Marjovi 2003studied the levels of 0, 25 and 50 tons per hectare of urban compost on sugar beet and wheat yield and stated that in the first year there was no significant difference between the different levels of compost application with the control. However, in the second year, due to ease of access of nutrient elements in compost fertilizer as a result of the activity of soil organisms, there was a significant difference between treatments of 50 tons per hectare and control. Results of the researchs conducted by the US Department of Agriculture showed that about 25% of nitrogen, 6-15% of phosphorus and 30-60% of potassium in the compost are released in the first year. This is because, contrary to chemical fertilizers, available nitrogen in compost fertilizers appears in the course of composting as bonds with other carbon-specific elements (Sikora and Smith, 2001). These bonds lead to the prevention of nitrogen leaching and groundwater pollution (Nyamangara, 2003).

 

Tuber dry weight and tuber nitrate content

 

Analysis of variance showed that fertilizer treatments had no significant effect on dry weight of tubers (Table 2). Mean comparisons (Table 3) showed that the highest percentage of tuber dry weight (17.67%) belonged to poultry manure and the lowest amount (15.23%) belonged to animal manure. Tuber dry weight reduced by increasing of the total number of tubers per square (Table 3). In lower density, plants have more access to water, light and nutrient, which increases the amount of net photosynthesis and tuber storage and as the result, dry matter of the tubers will increase (Roozbehani and Mirzaei, 2006).

Fertilizer treatments had significant effect on tubers nitrate content at 5% probability, level Table 2. Mean comparison (Table 3) showed that the highest percentage of nitrate in the tubers (217.96 mg/kg fresh weight) belonged to animal manure treatment, which was statistically the same as the amount poultry manure treatment (197.06 mg/kg fresh weight). The lowest nitrate contents (120.16 mg/kg fresh weight) belonged to vermicompost. Although the accumulation of nitrate in tubers depends on the consumption amount and type of nitrogen fertilizers, weather conditions, growth period and variety type, it should be noted that in most cases, the nitrate content of the tuber in potatoes exceeds the critical level due to the consumption and excess nitrogen absorption. According to references, the permitted nitrogen content in potato tubers is about 200-250 mg/kg of fresh weight of the tuber (Santamaria, 2006). If excessive nitrogen is absorbed by the plant, part of it will accumulate as nitrate in the tuber, and if nitrate levels exceed the permitted limit, it will be harmful to human health in the long term. Hypoxemia and the formation of nitrosamine-induced carcinogens are a side effect of excessive nitrate intakes (Roozbehani and Mirzaie, 2006). Since the percentage of nitrate in the tuber with the consumption of 25 tons animal manure per hectare and chemical fertilizer was close to the toxicity level, it seems that the use of this amount of organic and chemical fertilizer causes the harmful accumulation of nitrate in the tuber.  

 

 

 

 

  Tubers nitrate

 

Dry weight of tubers  

 

Total number of tubers

 

Large size tubers number

 

Medium size tubers number

 

Small size tubers number

Total tubers yield

 

Large size tubers yield

 

Medium size tubers yield

 

Small size tubers yield

 

df

Source of   modifications

 

1000.8 ns

0.072 ns

2.35ns

0.38ns

5.99ns

8.53ns

12.41 ns

1.47ns

6.18 ns

0.05 ns

2

replication

 

7957.6*

2.59 ns

62.00 *

7.2**

35.75*

6.25ns

86.41*

61.22 **

106.49*

2.68 ns

2

Treatment

 

624.2

1.03

8.63

0.09

6.49

3.55

12.73

0.72

8.25

1.13

4

Error

 

14.00

6.25

6.79

12.14

12.08

9.56

8.27

10.46

9.59

21.21

 

CV %

                           

Table 2. Analysis of variance of quantitative characteristics of potato

 

Ns,* and **:Non-significant and significant at 5% and 1% probability levels.

 

 

 

Table 3. The mean comparison of quantities characteristics by Duncan methods

 

Tuber nitrate

mg. kg-1

Dry weight of tubers

%

Total number of tubers

per m2

Large size tubers number

per m2

Medium size tubers number

per m2

Small size tubers number

per m2

Total tubers yield

 

ton. ha-1

Large size tubers yield

 ton. ha-1

Medium size tubers yield

ton. ha-1

Small  size tubers yield

 ton. ha-1

Treatment

 

197.06 a

17.67 a

38.13b

1.60b

17.69 b

18.89 a

36.97 b

5.92 b

24.95b

6.05a

Poultry manure

 

217.96 a

15.23 a

46.68a

4.28 a

21.03 ab

21.39 a

45.95 a

13.35a

28.41b

4.19 a

Animal manure

 

120.16 b

16.41 a

45.99 a

1.60 b

24.60 a

18.89 a

46.55 a

5.18 b

36.56 a

4.82 a

Vermicompost

 

In each column, means with similar letters have no significant differences

 

Conclusion

 

In general, the results of this experiment showed that the use of animal and vermicompost manure significantly increased the yield and yield components of potato. The application of vermicompost in comparison with animal manure increased the medium size tubers yield, while the application of animal manure in comparison to the application of vermicompost significantly increased the large size tubers yield. It is recommended that vermicompost be used in greenhouse and tuberous plants that require more light and appropriate soil and the use of chemical fertilizers be reduced due to their harmful and destructive effects. Examining different organic fertilizers in this study showed that vermicompost not only had an effect on potato yield increase, but it was also superior to poultry and animal manure in terms of human health and environmental pollution.  However, it should be noted, that the type of climate, variety and soil chemical composition will affect the type and amount of fertilizers used.

The resulted of this study showed that vermicompost application has superiority in terms of yield, maintaining human health and reducing environmental pollution (nitrate level) in comparison to animal and poultry fertilizers.

 

Acknowledgment

 

This research was supported by grants from the Agricultural Research, Education and Extension Organization (AREEO). We sincerely appreciate the time and effort that the dear colleagues at Jahad Agricultural Organization of Gotvand and the Soil and Water Research Institute of the Safiabad Agricultural and Natural Resources  Research and Education Center, have spent in the implementation of this project.

 

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