Scholarly article on topic 'Effect of different nitrogen sources on growth, yield and quality of fodder maize (Zea mays L.)'

Effect of different nitrogen sources on growth, yield and quality of fodder maize (Zea mays L.) Academic research paper on "Agriculture, forestry, and fisheries"

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Abstract of research paper on Agriculture, forestry, and fisheries, author of scientific article — Mohamed El-Murtada Hassan Amin

Abstract A field experiment was conducted for two consecutive seasons in 2004/2005 and 2005/2006 at the demonstration farm of the Faculty of Agriculture, Omdurman Islamic University, Sudan, to investigate the effect of different nitrogen sources on growth, yield and quality of fodder maize (Zea mays L.). The nitrogen sources are urea, nitrophoska (NPK), ammonium sulphate nitrate (ASN) and ammonium sulphate (AS). The design used was completely randomized block design with four replicates. The growth attributes measured, were plant height, stem diameter, number of leaves, leaf area, leaf area index. Number of days to 50% tasseling, forage yield, crude protein and crude fiber were also investigated in this study. The results revealed that nitrogen sources significantly affected growth parameters at all sampling occasions during the two seasons. Remarkable results noticed at nitrogen sources ASN flowed by NPK and the AS, as compared with urea. The results showed that, the number of the days for 50% tasseling, fresh forage yield and dry forage yield were significantly affected by nitrogen sources during two seasons. Moreover, dry and fresh forage yield, increased progressively by ASN and NPK as compared with other nitrogen sources. The present data revealed that, the crude protein and crude fiber were significantly affected by nitrogen sources in both seasons. The urea gave the lowest crude protein compared with the other nitrogen sources. On the other hand, the lowest crude fiber content was recorded when plant was treated with (ASN) fertilizer, while the highest crude fiber content was recorded only under the control.

Academic research paper on topic "Effect of different nitrogen sources on growth, yield and quality of fodder maize (Zea mays L.)"

King Saud University Journal of the Saudi Society of Agricultural Sciences

www.ksu.edu.sa www.sciencedirect.com

ORIGINAL ARTICLE

Effect of different nitrogen sources on growth, yield and quality of fodder maize (Zea mays L.)

Mohamed El-Murtada Hassan Amin

Crop Science Department, Faulty of Agriculture, Omdurman Islamic University, Sudan

Received 4 April 2010; accepted 9 June 2010 Available online 17 December 2010

KEYWORDS

Zea mays; Plant height; Stem diameter; Leaf area index; Forage yield; Forage quality

Abstract A field experiment was conducted for two consecutive seasons in 2004/2005 and 2005/ 2006 at the demonstration farm of the Faculty of Agriculture, Omdurman Islamic University, Sudan, to investigate the effect of different nitrogen sources on growth, yield and quality of fodder maize (Zea mays L.). The nitrogen sources are urea, nitrophoska (NPK), ammonium sulphate nitrate (ASN) and ammonium sulphate (AS). The design used was completely randomized block design with four replicates.

The growth attributes measured, were plant height, stem diameter, number of leaves, leaf area, leaf area index. Number of days to 50% tasseling, forage yield, crude protein and crude fiber were also investigated in this study.

The results revealed that nitrogen sources significantly affected growth parameters at all sampling occasions during the two seasons. Remarkable results noticed at nitrogen sources ASN flowed by NPK and the AS, as compared with urea.

The results showed that, the number of the days for 50% tasseling, fresh forage yield and dry forage yield were significantly affected by nitrogen sources during two seasons. Moreover, dry and fresh forage yield, increased progressively by ASN and NPK as compared with other nitrogen sources.

The present data revealed that, the crude protein and crude fiber were significantly affected by nitrogen sources in both seasons. The urea gave the lowest crude protein compared with the other nitrogen sources. On the other hand, the lowest crude fiber content was recorded when plant was treated with (ASN) fertilizer, while the highest crude fiber content was recorded only under the control.

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1658-077X © 2011 King Saud University. Production and hosting by Elsevier B.V. All rights reserved.

Peer review under responsibility of King Saud University. doi:10.1016/j.jssas.2010.06.003

1. Introduction

Maize (Zea mays L.) is a member of the family Poaceae. It was originated in Mexico where its oldest known ears could be traced back to about 7000 years ago (Mangeisdorf et al., 1964). In world production, maize is ranked as the third major cereal crop after wheat and rice. The crop has a wider range of uses. These include the following: human food, industrial

processed food production of starch and used as forage to feed animals. Maize with its large number of cultivars and different maturity periods has wider range of tolerance to different environmental conditions (Purseglove, 1972).

In Sudan, natural rangelands constitute about 45% of the total area of the country. This area supported about 80% of livestock (Ipperisiel et al., 1989). The major cultivated grass forage crops include Abu Sabein (Sorghum bicolor), Sudan grass (Sorghum sudanence), Tongna bean (Lablab purpureus), Alfalfa America (Medicago sativa), the hybrid Pioneer (S. bicolor x S. sudanence), and recently maize (Z. mays L.).

In Sudan, maize can be grown to produce forage in winter seasons to solve problems of livestock feed shortage during this period. Maize proved to be most suitable forage as it is characterized by its high energy content and considerable protein content, compared to other cereal forage crops (Ipperisiel et al., 1989). The reason behind planting maize for green forage production is to obtain succulent vegetative part in a comparatively short time (Toosey, 1972).

Maize plant as a whole is an important forage for many dairy and beef animals. The crop is palatable, quick growing with a high dry matter production and relatively high nutritive value. Dry matter yield of maize is a function of numerous interacting environmental and genetic factors. Temperature and available soil water are major environmental factors, with subsequent influence on leaf area development and subsequent dry matter yield (Dwyer and Stewart, 1986).

The leaf area and canopy structures are important growth parameters for forage production. The optimum leaf area index for grain production is considerably less than that for maximum dry matter production. Goldsworthy et al. (1974) demonstrated that when leaf area index was larger than five the additional dry matter produced accumulated mainly on the stem and therefore, leaf production can be increased by increasing leaf area per plant. All growth attributes that directly or indirectly affected forage yield and quality are affected by cultural practices as well as agricultural inputs.

Maize is commonly fed to livestock as fodder stover or silage (Christopher et al., 1966). The feeding of corn fodder is popular in the semi-arid as well as in areas where corn often fails to reach the stage of mature grain. The stalks of the crop at this stage are more palatable and higher in protein than other stages (John and Warren, 1967).

Forge yield in maize increases and quality decreases rapidly as plant matures (Jung and Barkjer, 1973), indicating that harvesting at early heading stage is generally the right time to produce high forage yield with high quality. When maize is grown for silage it is harvested 2-3 weeks earlier than maize harvested for grain. Pain (1978) reported that when maize is the most suitable crop to be grown for silage in temperate countries, forage maize become one of the most important feed stuff for ruminants specially cattle (Rouanet, 1987).

Forage maize compared to other grasses has a relatively high content of non-structural carbohydrates. In case of silage maize, sugars within the cell and the water soluble carbohydrates are more important in the preservation of the silage material (Pain, 1978). Other carbohydrate sugars are often added to the crop for silage making.

In some performance studies, the introduced variety 8742, recorded the highest relative growth rate, leaf area and dry weight as compared to Mugtama 45 and Tlatizapan 8743 (Mohamed, 1997). Therefore, the selection of cultivars for

forage production may be an important management practice, because it influences the nutritive value (Graybill et al., 1991).

Nitrogen element is the nutrient that most frequently limits yield and plays an important role in quality of forage crops. It is almost deficient in most soils of Africa and most of the tropics (Jules, 1974).

Positive response of nitrogen fertilizers has been reported by Koul (1997), Omer (1998), Gasim (2001) and Sawi (1993). Sharma (1973) observed that addition of nitrogen fertilizer increased plant height. Increase in plant height resulted in an increase in leaf number per plant as reported by Akintoye (1996).

Gasim (2001) indicated that the increase in plant height with nitrogen fertilizer is due to the fact that nitrogen promotes plant growth, increases the number of internodes and length of the internodes which results in progressive increase in plant height. Chandler (1969), Turkhede and Rajendra

(1978) and Koul (1997) reported similar results.

Nitrogen fertilization increased number of leaves per plant and leaf area (El Noeman et al., 1990; Gasim, 2001). John and Warren (1967) noted that the addition of nitrogen increased stem diameter. Koul (1997) recorded that nitrogen application resulted in greater values of plant height, leaf area, number of leaves and stem diameter of fodder maize, fresh and dry forage yield were also increased due to addition of nitrogen. Leaf to stem ratio was found also to be increased by nitrogen (Duncan, 1980). These findings are in full agreement with that of Gasim (2001) who reported that the increase in leaf to stem ratio with nitrogen application is probably due to the increase in number of leaves and leaf area under nitrogen treatments, producing more and heavy leaves.

The uptake of nitrogen by maize is low during early development and increased at tasseling. Although only relatively small amounts of fertilizers are required during the very early stages of plant growth, high concentration of nutrients in the roots zone at that time are beneficial in promoting early growth (Ritchie et al., 1993). Gasim (2001) has observed that nitrogen fertilization accelerated the time to reach 50% tassel-ing, promoted the fresh and dry forage weight. Salem and Ali

(1979) found that nitrogen application increased the number of ears per plant, ear height, number of days to mid-silking and protein content, and decreased the number of barren stalks.

Grain protein content was increased by nitrogen (Warren et al., 1975; Gangwar and Kalra, 1988). Increased protein content in maize straw was obtained with increased dose of nitrogen (Rai, 1965). Tripathi et al. (1979) found that application of nitrogen gave a significant additional increase in crude protein contents of forage oats.

Kalifa et al. (1981) studied the effect of nitrogen on an open-pollinated variety of corn which was given as ammonium nitrate applied as nitrogen source. His results indicated that ammonium nitrate fertilizer increased the number of days to mid- tasseling, mid-silking and shelling percentage. Singh et al. (1986) found that the biological yield, content and uptake of nitrogen in grain and stover of maize were highest with nitrogen as urea applied in two split dressings. Sawi (1993) and Omara (1989) observed that nitrogen had significant effects on chemical composition of leaves, plant height, leaves, internodes number per plant at early stages. Shoat and root dry weight and cob number per plant. Nitrogen also significantly affected final seed yield and some yield components such as number and weight of cobs/m2 and weight of seeds per cob, also significantly affected straw yield. In addition

nitrogen had significant effect on seed protein content and seed and leaf P content. Gasim (2001) found that the addition of nitrogen increased forage fresh and dry yield, also increased percentage of crude protein in leaf stem.

The main objectives of this study were to investigate the influence of different nitrogen sources on growth, yield and quality of fodder maize under irrigation.

2. Materials and methods

The experiment was conducted for two consecutive seasons in 2004-2005 and 2006 at the demonstration farm of the Faculty of Agriculture, Omdurman Islamic University. The soil is generally sandy clay loam, non-saline and non-sodic with pH (7.8). Treatments involved in the experiment consisted of different nitrogen sources. Nitrogen dose used for each treatment was in 43 kg N/ha. The different nitrogen sources were as follows: urea (46%N), nitrophoska (18%N + 18%P2O2 + 5%K2O + microelements) and ammonium sulphate nitrate (26%N + 14%S). Ammonium sulphate (21%N + 24%S)was used as controls.

The treatments were arranged in completely randomized block design with four replications. The seeds were sown in the first week of November for two seasons (plant cv. Mog-tama-45). The plot area was 20 m2, each plot included seven ridges, and each ridge was 6 m in length and 60 cm apart.

Nitrogen fertilizers were applied once at sowing before the first irrigation. The crop was irrigated eight times in each season at intervals of 10-14 days. Growth attributes measured were plant height, stem diameter, number of leaves, leaf area, and leaf area index. The plants were chosen and removed from each plot randomly after 45, 60, 75 and 90 days form sowing. Number of days to 50% tasseling, forage yield, crude protein and crude fiber were also investigated in this study. For the seasons analysis of variance was performed and means were compared using least significant difference (LSD) (Gomez and Gemez, 1984).

3. Results and discussion

3.1. Growth parameters

The obtained results revealed that plant height was significantly affected by applied different nitrogen sources in both

seasons at all growth stages (Table 1), with highest plant height obtained by ASN treatment.

The increase in plant height with different nitrogen sources can be attributed to the fact that nitrogen promotes plant growth, increases the number and length of the internodes which results in progressive increase in plant height.

Similar results were reported by Sharma (1973), Turkhede and Rajendra (1978), Koul (1997), Saigusa et al. (1999) and Gasim (2001). However, the remarkable increase in plant height attained by (ASN) treatment, in this study can be explained by the efficiency of nitrogen source which composed of two forms (ammonium and nitrate) and sulfur as essential nutrient for the plant. This result is in agreement with the finding of Sahid et al. (1990), Omara (1989), Bindra and Kharwara

(1994), Elmar (2001) and Abdel Gader (2007).

Data in Table 2 shows that stem diameter was significantly increased in all treated plants at all sampling occasions during the two seasons. The largest stem diameter was significantly increased in all treated plants at all sampling occasions during the two seasons. The largest stem diameter was noticed at the nitrogen source ASN flowed by NPK and the AS. The increase in stem diameter due to application of nitrogen can be explained by the fact that nitrogen promotes plants growth. On the other hand the increase in stem diameter due to the application of ASN and AS can be ascribed to the presence of sulfur as reported by Elmar (2001). The increase of stem diameter as a result of NPK applications may be due to the fact that, this nitrogen source was composed of many nutrients (N, P and K).

As shown in Table 2 the number of leaves per plant is significantly increased when fertilized with different nitrogen sources in both seasons. Whereas, fertilizing with urea produced the lower number of leaves as compared with other sources. The increase in the number of leaves per plant could possibly be ascribed to the fact that nitrogen often increases plant growth and plant height and this resulted in more nodes and internodes and subsequently more production of leaves. In this respect, Okajina et al. (1983), Sawi (1993) and Jhones et al.

(1995) found that nitrogen fertilization, significantly increased the number of leaves and they suggested that the increasing in number of leaves may be as a result of increasing number of nodes.

The effect of different nitrogen sources on leaf area at different growth stages during two seasons is presented in Table 3. The revealed values indicated that leaf area was significantly

Table 1 Effect of different nitrogen sources on plant height (cm) of maize during 2004/2005 and 2005/2006 seasons.

Plant age (days) Treatments LSD at 5%

Control NPK ASN AS Urea

Season 2004/2005

45 24.50 40.30 54.50 45.00 39.80 19.86

60 35.30 59.00 79.50 57.00 53.80 15.14

75 43.00 79.30 100.80 75.30 55.50 26.17

90 15.00 93.50 112.00 81.50 80.50 20.72

Season 2005/2006

45 36.50 46.30 51.80 42.90 38.40 4.80

60 49.40 79.90 95.90 72.50 61.10 13.10

75 50.10 90.80 106.60 73.60 68.60 12.40

90 64.70 117.80 152.90 93.50 86.50 23.40

Table 2 Effect of different nitrogen sources on stem diameter (cm) and number of leaves of maize during 2004/2005 and 2005/2006 seasons.

Treatment Stem diameter Number of leaves

Plant age

45 60 75 90 45 60 75 90

Season 2004/2005

Control 3.3 4.8 5.0 5.5 8.3 8.8 9.5 10.7

NPK 4.8 5.5 5.8 6.8 10.6 11.7 13.7 14.1

ASN 4.8 5.8 6.3 7.0 11.5 12.9 14.2 14.9

AS 4.3 5.3 5.8 6.0 9.5 10.5 12.6 13.2

Urea 4.0 5.3 5.5 5.8 9.2 9.8 11.7 12.4

LSD at 5% 0.16 0.21 0.16 0.83 0.50 0.25 0.25 0.18

Season 2005/2006

Control 3.9 4.5 5.4 5.8 9.5 10.0 10.9 12.1

NPK 4.7 5.4 6.8 7.0 11.8 12.9 14.1 15.3

ASN 5.0 5.6 6.9 8.6 12.7 14.1 15.3 16.5

AS 4.3 5.1 6.1 6.8 11.2 11.7 12.9 14.1

Urea 4.0 4.8 5.6 6.0 10.4 10.9 11.1 12.3

LSD at 5% 0.10 0.16 0.20 0.81 0.70 1.01 0.90 1.01

Table 3 Effect of different nitrogen sources on leaf area (cm2) and leaf area index (LAI) of maize during 2004/2005 and 2005/2006 seasons.

Treatment Leaf area Leaf area index

Plant age

45 60 75 90 45 60 75 90

Season 2004/2005

Control 190.9 191.9 254.1 256.2 0.9 2.4 3.0 5.1

NPK 310.8 311.2 413.2 415.1 1.5 6.0 6.9 7.5

ASN 340.8 346.6 454.2 460.5 1.5 6.9 7.5 8.1

AS 272.1 280.3 369.1 372.9 1.2 5.1 6.3 6.9

Urea 250.1 260.6 358.6 359.0 1.1 4.2 5.4 6.3

LSD at 5% 8.6 8.1 8.3 17.5 0.21 0.51 0.41 0.50

Season 2005/2006

Control 166.20 167.50 190.30 200.01 0.6 1.6 3.0 3.4

NPK 206.52 210.87 215.60 218.09 1.0 4.0 4.6 5.0

ASN 223.50 225.45 233.67 136.67 0.2 4.6 5.0 5.2

AS 189.40 196.50 203.14 204.67 0.8 3.4 4.2 4.5

Urea 172.32 181.87 199.30 201.60 0.8 2.8 3.6 3.9

LSD at 5% 16.08 13.87 8.01 31.67 0.11 0.55 0.38 0.41

affected by applied treatments at all sampling occasions in both seasons. However, nitrogen enhanced growth and consequently influences leaf expansion and development. These results coincided well with Watson (1952), El Noeman et al. (1990), Filatov and Afonin (1993) and Sayed (1998). They stated that nitrogen significantly increased leaf area through effect on elongation of leaves.

The data presented in Table 3 reveals that, applying different source of nitrogen on leaf area index (LAI) had significant effect at all growth stages in both seasons. Increasing in LAI may be due to the fact that addition of nitrogen from different source in this investigation increased number of leaves and total leaf area per plant and their effect on enlargement of leaves

cell. This result agrees with those obtained by Rageb et al. (1990) and Lemocof and Loomis (1994).

3.2. Reproduction attributes

The present study showed that, the number of days to 50% tasseling is significantly affected by different nitrogen treatments during the two seasons studied (Table 4). Nitrogen application accelerated the time to reach 50% tasseling as compared to control. These results are fully in line with the findings of Richard et al. (1983) who reported that nitrogen decreased the interval form seeding to flowering.

Table 4 Effect of different nitrogen sources on number of days to 50% tasseling, fresh forage yield and dry forage yield of maize during 2004/2005 and 2005/2006 seasons.

Treatment Days to 50% tasseling 2004/2005 2005/2006 Fresh forage yield (ton/ha) 2004/2005 2005/2006 Dry forage yield (ton/ha) 2004/2005 2005/2006

Control 49.8 51.0 17.70 29.80 7.40 7.20

NPK 45.3 45.3 40.70 58.00 13.40 13.30

ASN 44.0 44.2 48.60 70.40 15.70 15.50

AS 47.0 46.3 29.60 41.90 10.40 10.40

Urea 48.5 49.0 26.40 34.25 9.20 9.30

LSD at 5% 1.2 0.9 1.20 31.15 0.24 0.31

Table 5 Effect of different nitrogen sources on crude protein (%) and crude fiber of maize during 2004/2005 and 2005/2006 seasons.

Treatment Crude protein Crude fiber

Leaf protein (%) Stem protein (%) Leaf fiber (%) Stem fiber (%)

Season 2004/2005

Control 7.00 7.30 28.95 29.97

NPK 9.30 8.89 26.63 27.65

ASN 9.77 9.43 25.25 26.27

AS 8.41 8.52 27.45 28.47

Urea 7.50 7.28 28.47 29.49

LSD at 5% 0.08 0.11 0.34 0.40

Season 2005/2006

Control 6.49 6.48 28.73 29.84

NPK 8.29 8.33 26.53 27.64

ASN 8.76 8.79 25.25 26.36

AS 7.40 7.42 27.46 28.57

Urea 7.00 60.98 28.40 29.51

LSD at 5% 0.29 0.44 0.19 0.51

The attained results showed that, different sources of nitrogen significantly affected the fresh yield of the forage as compared with the control during both seasons (Table 4). Moreover, the fresh forage yield increased progressively by ASN and NPK treatments as compared with other nitrogen sources both in treatments and control particularly, in the second season. The increase in fresh yield of forage under nitrogen application can be attributed to the positive effect of nitrogen on all the growth parameters investigated in this study. These findings are in conformity with the findings of other investigators particularly, Ellis et al. (1956), and Singh et al. (1992). Fresh forage weight in the second season was heavier than in the first season. This was attributed to the logging that accrued during the first season. The high moisture content of the forage in the second season was due to the fact that, the sampling was done when the field was under irrigation. The high forage fresh weight obtained under ASN and NPK treatments was due to the efficiently of those treatments. This result is also in agreement with Elmar (2001) and Abdel Gader (2007).

The results summarized in Table 4 revealed that, nitrogen application significantly influenced dry forage weight during the two seasons studied. Forage yield is a function of growth parameters. As shown earlier in this study, all growth parameters were affected by nitrogen fertilization from different sources. The differences in dry forage matter yield may be

due to the nutrients included in each nitrogen source, which was higher when plants were treated by ASN and NPK. These results were in full conformity with those reported by El Amin (2003) and Abdel Gader (2007).

3.3. Forage quality

The crude protein of leaf and stem of forage were significantly affected by different nitrogen sources in both seasons (Table 5). The urea treatment gave the lowest crude protein as compared with the other nitrogen sources. Increasing of crude protein content may definitely, be due to the fact that nitrogen often plays a great role in the synthesis of protein.

Similar results regarding the increased percentage of crude protein due to applied nitrogen were obtained by several research workers (for example, Parsad, 1979; Singh et al., 1992; Gangwar and Kalra, 1988; Koul, 1997; Khandaker and Islam, 1988).

The effect of different nitrogen sources on leaf and stem crude fiber of fodder maize was significant during the two studied seasons (Table 5). The nitrogen sources application reduced leaf and stem crude fiber content. However, the lowest crude fiber content was recorded when plants were treated with (ASN) fertilizer, while the highest crude fiber content was recorded under the control treatment (i.e. without nitrogen).

These results are in full agreement with the results reported by Sandhu et al. (1976), Koul (1997) and Gasim (2001).

4. Conclusion

The results revealed that nitrogen sources affected growth parameters at all sampling occasions. Nitrogen enhanced tas-seling and decreased the number of days to 50% tasseling. Also, fresh and dry forage yield was significantly affected by nitrogen sources. Moreover, fresh and dry forage yield, was increased progressively by ASN and NPK as compared with other nitrogen sources.

Crude protein and crude fiber were affected by nitrogen sources (NPK, ASN and AS). The urea gave lowest crude protein compared with other nitrogen sources. On the other hand, the lowest crude fiber content was recorded when plants were treated with (ASN) fertilizer, while the highest crude fiber content was recorded only under the control.

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