WHEAT BIOMASS AND HARVEST INDEX INCREASES WITH INTEGRATED USE OF PHOSPHORUS, ZINC AND BENEFICIAL MICROBES UNDER SEMIARID CLIMATES

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October – November 2019, vol. 9, no. 2
pages: 242-247
Article type: Food Sciences of Food Sciences
DOI: 10.15414/jmbfs.2019.9.2.242-247
Abstract: Under semiarid climate, the higher soil pH and alkalinity reduce phosphorus (P) availability and thus crop productivity. The higher prices of P-fertilizers restrict small holders to apply the required P level to their field crops. Proper P management under semiarid climates is very essantail for increaase crop productivity of smallholders. An expriemnt was work out in 2013-15 to study the impact of P management on wheat total biomass and harvest index. The expriment was worked out at the University of Agriculture, Agronomy research farm. In experiment one, treatments were: four P levels (100, 80, 60 and 40 kg P ha-1), three levels of zinc (15, 10 and 5 kg Zn ha-1) and three timings of beneficial microbes (BM) timings of application (at sowing, 20 DAE and 40 DAE). It was concluded from the experiment one, that application of 80 kg P ha-1 + 15 kg Zn ha-1 along with BM at 20 DAE produced higher wheat biomass and harvest index. In experiment two, treatments were: four P-fertilizers sources (TSP, DAP, SSP, NP), four P levels (120, 90, 60, 0 kg P ha-1) and three varieties of wheat (Shahkar-2013, Pirsabak-2013, and Atta-Habib-2010). The results indicated that maximum biomass yield and harvest index was calculted with SSP application. Maximum biomass and harvest index was produced with 120 kg P ha-1 application to the soil. Among wheat varieties Pirsabak-2013 perform better than others by producing higher harvest index and biomass.
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WHEAT BIOMASS AND HARVEST INDEX INCREASES WITH INTEGRATED USE OF PHOSPHORUS, ZINC AND BENEFICIAL MICROBES UNDER SEMIARID CLIMATES


AUTHORS

Amanullah, Nangial Khan, Muhammad Ibrahim Khan, Shah Khalid, Asif Iqbal, Abdel Rahman Al-Tawaha

ABSTRACT

Under semiarid climate, the higher soil pH and alkalinity reduce phosphorus (P) availability and thus crop productivity. The higher prices of P-fertilizers restrict small holders to apply the required P level to their field crops. Proper P management under semiarid climates is very essantail for increaase crop productivity of smallholders. An expriemnt was work out in 2013-15 to study the impact of P management on wheat total biomass and harvest index. The expriment was worked out at the University of Agriculture, Agronomy research farm. In experiment one, treatments were: four P levels (100, 80, 60 and 40 kg P ha-1), three levels of zinc (15, 10 and 5 kg Zn ha-1) and three timings of beneficial microbes (BM) timings of application (at sowing, 20 DAE and 40 DAE). It was concluded from the experiment one, that application of 80 kg P ha-1 + 15 kg Zn ha-1 along with BM at 20 DAE produced higher wheat biomass and harvest index. In experiment two, treatments were: four P-fertilizers sources (TSP, DAP, SSP, NP), four P levels (120, 90, 60, 0 kg P ha-1) and three varieties of wheat (Shahkar-2013, Pirsabak-2013, and Atta-Habib-2010). The results indicated that maximum biomass yield and harvest index was calculted with SSP application. Maximum biomass and harvest index was produced with 120 kg P ha-1 application to the soil. Among wheat varieties Pirsabak-2013 perform better than others by producing higher harvest index and biomass.


KEYWORDS

phosphorus, levels, sources, wheat, varieties, zinc levels, beneficial microbes

INTRODUCTION

Globally, among cereal crops in the world and also in Pakistan, wheat (Triticum aestivum L.) is the most important crop (Tunio 2006; Malik 2006), which is grown on about 37% cropped area. In Pakistani agricultural and GDP, wheat contributes considreble share (14.4%, 3% ), respectively. Despite of being grown in larger area in the country, average yield of wheat at smallholder’s fields is still far below the genetic potential of the crop (Mann et al. 2004). Accoreding to Singh and Singh  (2001)  that wheat crop is depliting soil fertility and also physical properties of the soil.

Productivity and growth of plant is affected by many enoronnametal and biotic factors (Al-Rifaee et al. 2004; Musallam et al. 2004; Tawaha and Turk 2004; Turk et al. 2004; Al-Tawaha and Seguin 2006). After nitrogen, Phosphorus stay 2nd key macro nutrient which have a key role in plant metabolisam (Turk and Tawaha 2001; Tawah and Turk 2002b; Turk and Tawaha 2002;  Turk et al. 2003; Nikus et al. 2004; Mehrvarz et al. 2008, imranuddin et al., 2017). Most of Pakistani soil is low in avaliblie phosporus (Nisar et al. 1992; Ahmad et al. 1992). For sustainable production P availability under semiarid condition is major problem (Brady and Weil 2002). Unlike nitrogen, phosphorus is relatively immobile in the soil. Unforutnalty, rainfed areas of Khyber Pakhtunkhwa have lack of optimum moisture  low organic matter and low soil fertility (Amanullah et al. 2009a; Amanullah et al. 2010a). Pakistani soils have pH ranging from 7 to 9 with high calcium carbonate, which promate relatively insoluble dicalcium phosphate (Hussain and Haq 2000). High concentration of calcium compounds is responsible for decreasing phosphorus deficiency and decreasing crop yield (Ibrikci et al. 2005).

Phosphorus fertilzer availbe in the market in different types like TSP, DAP, SSP, MAP and NP.  Among them DAP is imoprted other countries. Incase of micronutrients, Zn is play an important role in several physiological functions, plant metabolism and activation og enzymes (Tisdale et al. 1984; Marschner 1995; Cakmak 2000). Zinc deficiency affect sandy soils, calcareous, peat soils,  high phosphorus soils and consider to be the wide spreed difficency globally and also almost all crops (Amanullah and Inamullah 2016).

In semiarid climates P availability  can be improved by application of beneficial microorganism (BM) (Tripura et al. 2005; El-yazeid et al. 2007; Venkatashwarlu 2008; Walpola and Yoon 2012). Beneficial microorganisms inceasere plant resistance toword disease and pest attack and improve crop growth (El-yazeid et al. 2007). Our recent published research indicates that beneficial microbes and thereby improve growth, yield and yield components in cereal crops e.g. in wheat (Amanullah et al. 2016; Amanullah Khan 2017) and maize (Amanullah and Khalid 2016; Amanullah and Khan 2015).

Different types soil bacteria and fungai are responsible for converting soil unavalible P into availpbe obe bu the relasing of different oganics compound which are acidic in anture, which decrease soil PH and thereby increase phosphorus availability (Walpola and Yoon 2012). Use of microoganism is not only useful for higher crop production on susutaiblre bases but also decrease the use of chemical fertlizers. (Hafeez et al. 2002).

Keeping in view the job of phosphorus and zinc and helpful small scale life form application time, the present investigation was intended to consider the development and yield reaction of wheat verities to phosphorus, zinc and BMO for improving wheat efficiency in the examination region.

MATERIAL AND METHODS

Site description

Texture clay loam Amanullah et al., (2009) and Amanullah et al., (2010)
P contents (Extractable) 6.57 mg kg−1
Organic Matter 0.87%
K contents (Extractable) 121 mg kg−1
pH 8.2
Annaul Rainfall 300-500 mm
Climate Subtropical

Two huge field experiments were conducted for studing the affect  of phosphorus (P) levels and sources (S) on wheat during winter 2013-2015 at the University of Agriculture Peshawar, Agronomy Research Farm.

Treatments used in experiment one

Experiment one was carried out in winter 2013-14 (year one). The factors and their respective levels are;

Control = (No P and no Zn applied)

Factor (A):     Phosphorous levels (kg ha-1)

P1   = 40

P2   = 60

P3   = 80

P4   =100

Factor (B):              Zinc levels (kg ha-1)

Zn1 = 5

Zn2 = 10

Zn3 = 15

Factor (C):             Beneficial microbes (BM) application Timings

EM1 = At Sowing

EM2 = 20 DAE (days after emergence)

EM3 = 40 DAE

The experiment was worked out in RCBD with extention of split plot arrangement repeated 3 times. Combination of four P levels (factor A) and three Zn levels (factor-B) along with one control plot (no P and Zn applied) was used as main plot factors (4 x 3 = 12 + 1 = 13 main plots), and three BM application timing (factor C) as sub plots factor (13 x 3 = 39 total treatments per replication was used). Plot size of 2.4 m x 3.0 m having 8 rows was used for each treatment (39 x 3 = 117 sub-plots in the whole experiment two). DAP and ZnSO4 was used as sources of P and Zn, respectively along with BIOAAB is a source of BM (12.5 liter ha-1) were used. Urea was used is a soucre of N at the rate of (140 kg N ha-1). Both the nutrinnts( P and Zn) was totally applied and incorotated in the soil during sowing time while N was apllied in two equal splits, half at sowing and half at 2nd irrigation. Wheat verity (siran) was sown at row to row distance of 3 cm at the rate of 120 kg ha-1.

Experiment two

Experiment two was carried out in winter 204-15 (year two), with follwing factors

Control = (P zero application)

Factor (A):                           Sources  of Phosphorous

S1 = TSP

S2 = SSP

S3 = NP

S4 = DAP

Factor (B):                              Levels of Phosphorus (kg ha-1)

P1  = 120

P2   = 90

P3   = 60

Factor (C):                             Wheat varieties

V1 = Atta Habib-2010

V2 = Shahkar­-2013

V1 = Pirsabak-2013

The expriemnt was workedt out in RCBD  with extension of split plot arrangement. Four levels of  P and three P sources along with one control plot (no P and Zn applied) was allotted to main plots (4 x 3 = 12 + 1 = 13 main plots) and factor-C (varieties) were allotted to sub plots (13 x 3 = 39 total treatments per replication was used). Plot size of 2.4 m x 3.0 m having 8 rows was used for each treatment (39 x 3 = 117 sub-plots in the whole experiment one). All of the studies veraity of wheat was sown at the rate of 120 kg ha-1 with row to row distance of 30 cm. The required P rates in the form of NP, TSP, DAP and SSP was incorported in the soil during  seedbed preparation at sowing.

Data recording and handling

Biological yield of wheat was calculted by the following formula.

Grain yield (kg ha-1)       

       

Harvest index (HI)

HI was calculated by the below mention equation

Where as GY and BY stand for grain and biological yield, respectively

RESULTS AND DISCUSSION

Experiment # 1

Biomass

Data concerning biomass yield of wheat is shown in table 1 showed that  zinc and phosphorous levels, Zn x P interaction and control vs rest was signifecnlty affected biomass f wheat. A considerable decrease in bomass of higher than 2000 kg ha-1 was calculated in compersion of control and treated plots (P znc Zn). Incase of P application highest biomass (11365 kg ha-1) was recoreded when P was applied at the rate of 80 kg ha-1 which ws statiscally at par with 100 kg P ha-1 (11544 kg ha-1), while at 40 kg ha-1 of P application lowest biomass (11039 kg ha-1) was recoreded (Table 2). Zinc application at the rate of  15 kg ha-1 produced highest biomass (11039 kg ha-1) while Zn appllication at the rate of 5 kg ha-1 produeced lowest biomass of wheat (10541 kg ha-1) which was statistically at par with 10 kg Zn ha-1. the interactive effect of both nutrunts showed that, increase both levels of the nutrient increase wheat biomass, the highest biomass of wheat (12354 kg ha-1)  was calculated when P ans Zn was applied at the rate of 80 and 15 kg ha-1, respectively (Fig 1).

Table 1  Analysis of variance for total biomass yield (kg ha-1) and harvest index (%) of wheat as affected by P and Zn level and EMO application timings in year one

Source of variance D.F. Total Biomass Harvest index
Probability Significance Probability Significance
Replications {2}
Treatments [12] 0.000 ** 0.000 **
Zn (2) 0.003 ** 0.017 *
P (3) 0.000 ** 0.005 **
P x Zn (6) 0.020 * 0.104 ns
Control vs. rest (1) 0.000 ** 0.000 **
Error I {24}
EMO timings {2} 0.278 ns 0.748 ns
Treatments x EMO [24] 0.969 ns 0.909 ns
Control vs. rest x EMO (2) 0.275 ns 0.192 ns
Zn x EMO (4) 0.747 ns 0.873 ns
P x EMO (6) 0.961 ns 0.868 ns
Zn x P x EMO (12) 0.915 ns 0.816 ns
Error II {52}
Total 116 CV1= 5.2% CV2= 4.8% CV1= 5.7% CV2= 6.7%

Figure 1 Interactive effect of phosphorus and zinc on biomass yield (kg ha-1) of wheat in year one (Exp. 1).

Harvest index (HI)

HI of wheat was signifeclty afftected by Zn,P, P x Zn and control vs rest (table 1). Time of application of benifical microoraginsim and thair interactions were not signifectly harvest index of wheat. Treated plots (P and Zn application) produced higher harvest index (39.5 %) as comperad with control plots (34.1%).  Incase of P application, highest harvest index was recoreded when 80 kg P ha-1 was applied  as compared with all other P levels which produced statistically the same but lower harvest index (Table 2). Zn application at higher rate (15 kg ha-1) produed higher harvest index (40%) which was statisticaly at par with 10 kg ha-1 while the lowest harvest index (38.5 %) was calculated for 5 kg Zn ha-1 (Table 2).

Table 2 Biomass yield (kg ha-1) and harvest index (%) of wheat as affected by phosphorus (P), zinc (Zn) and effective microorganism (EMO) application timings in year one

P levels kg ha-1 Biological yield (kg ha-1) Harvest index (%)
40 9483 c 38.9 b
60 10702 b 38.8 b
80 11365 a 41.0 a
100 11544 a 39.4 b
Significance ** **
Zinc levels (kg ha-1)
5 10541 b 38.5 b
10 10741 b 39.9 a
15 11039 a 40.0 a
Significance ** *
EMO timings
Emergence 10761 39.3
20 DAE 10877 39.8
40 DAE 10683 39.4
Significance Ns ns
Control 8607 34.1
Rest 10774 39.5
Interactions
Zn x P *(Fig. 1) ns
Zn x EMO Ns ns
P x EMO Ns ns
Zn x P x EMO Ns ns

Experiment # 2

Biomass yield

Different souces of P and P levels as well as control vs rest signifectly affected wheat biomass, while all of thair interaction was found not signifecnt. Incase of control vs rest highest biomass  was produced in treated plots (10704 kg ha-1) as compered with control plots (9525 kg ha-1). incase of P sourecs highest biomass was produed (10852 kg ha-1) when SSP was used as sourese of P, which was statisticaly at par with application of NP as sourece of P (10735 kg ha-1), while application of DAP produed lowest biomass of wheat (10568 kg ha-1) (Table 2). incase of  P application, hihest biomass was produec when P was applied at 120 kg ha-1, followed by  90 kg P ha-1 (10657 kg ha-1), while application of 60 kg ha-1 prouded lowest biomass of wheat (10391 kg ha-1). Although the differences in biomass varieties were not-significant, yet variety Pirsabak-2013 ranked first by producing the highest biomass (10776 kg ha-1), as compered with Shahkar-2013 and Atta-Habib which produed lower biomass of wheat (10724 kg ha-1, 10776 kg ha-1), respectively (Table 4).

Table 3   Analysis of variance for biomass yield (kg ha-1) and harvest index of wheat varieties as affected by phosphorus sources and their levels in year two

Source of variance D.F. Total Biomass Harvest index
Probability Significance Probability Significance
Replications {2}
Treatments (Tr) [12] 0.000 ** 0.000 **
P levels (2) 0.000 ** 0.000 **
P Source (3) 0.000 ** 0.008 **
PL x PS (6) 0.439 ns 0.963 *
Control vs. Rest (1) 0.000 ** 0.000 **
Error I {24}
Varieties {2} 0.051 ns 0.000 **
Treatments x varieties [24] 0.751 ns 0.285 ns
Control vs. rest x varieties (2) 0.008 ns 0.093 ns
PL x Varieties (4) 0.883 ns 0.110 ns
PS x Varieties (6) 0.801 ns 0.322 ns
PL x PS x Varieties (12) 0.984 ns 0.720 ns
Error II {52}
Total 116 CV1= 7.6% CV2= 5.7% CV1= 2.2% CV2= 2.3%

Harvest index

Harvest index of wheat had sigifeclty affected by P sourecs, levels as well as control vs rest (table 3). All the interaction was found not signifecnt except PL x PS. Higher harvest inde was calculated in treated plots (35.41%) as compared with control (32.37%). Incase of P sorces, highest harvest index (35.8%) was produed in SSP applied plots, which statistical simialar with NP, while apllivation of Dap produced lowe harvest index (34.8%) as mention in table 4. Among the P levels, P application at the rate of 120 kg ha-1 produced ighest harvest inex (36.7%) which was statistcaly simialr with application of 90 kg P ha-1, followed by 60 kg P ha-1. in case of verital compersion Pirsabak-2013, performe better in tarm of harvest index followed by  Atta-Habib-2010 which was statisticaly similar with Shahkar-2013 (35.2 % and 34.8 %), respectively.

The PL x PS showed that phosphorus from single super phosphate at two higher levels increased the harvest index of wheat varieties as compared at other sources at lower levels (Fig. 2).

Table 4   Biomass yield (kg ha-1) and harvest index (%) of wheat varieties as affected by phosphorus sources and their levels in year two

Phosphorus Sources Biological yield (kg ha-1) Harvest index (%)
SSP  10852 a 35.8 a
TSP    10662 bc 35.2a b
DAP  10568 c 35.0 b
NP    10735 ab 35.6 a
Significance ** **
Phosphorus levels (kg ha-1)
60 10391 c 33.2 b
90 10657 b 36.3 a
120 11064 a 36.7 a
Significance ** **
Varieties
Pirsabak 2013 10776 a 36.2 a
Shahkar 2013 10724 a 35.2 b
Atta-Habib 2010 10682 a 34.8 b
Significance ns **
Control 9525 b 32.37 b
Rest 10704 a 35.41 a
Interactions
PL x PS ns *(Fig. 2)
PL x Varieties ns Ns
PS x Varieties ns Ns
PL x PS x Varieties ns Ns

Figure 2 Interactive effect of phosphorus levels and sources on harvest index (%) of wheat in year two (Exp. 2).

DISCUSSION

Control vs. Rest

The improvement in biomass yield in the rest (treated plots) over control was attributed to the increase in plant height, leaf area indexleaves plant-1, and yield components.  From our recent prievius research (Amanullah et al. 2014) we have concluded that tretated plots have suffincet plant ntruntrint which contribute to increase plant height, leaves plant-1 and leaf area, as well as higher yield and yield components and so had higher biomass yield over control plots. The phosphorus treated plots in wheat produced 8.8 % more dry matter m-2 over control (Amanullah et al. 2015).

Increase in harvest index of wheat in the rest (treated plots) over control was contributed to the improvement in crop growth, yield components, grain yield and especially more dry matter partitioning into the wheat reproductive parts (spikes). According to Amanullah et al. (2015), proper phosphorus nutrition for wheat partitioned more DM into the spikes (59%) than its stem (21%) and leaf (20%). The phosphorus treated plots partitioned about 7.5% more dry into the spike than control (Amanullah et al. 2015).

Phosphorus levels

Application of higher P level produced tillers density of wheat, leaf number and area, plant height, grains spike-1 and ultimately the biomass yield (Khan et al. 2009; Lu and Barber 1995).

Higher rate of P inmprove wheat harvest index, it might be due P contributuion in yield and yield components. Similar results was also reported by Saber et al. (2010) who stated that higher rate of P increase wheat crop grain yield and harvest index. P applicatiion increase grain spike-1 Memon et al. (2011) and Rahim et al. (2010)  which will contribut to final yield  (Amanullah et al. 2014). In our recent research on rice (Amanullah and Inamullah 2016), we obtained maximum harvest index (41.4%) was calculated for the highest P level of 120 kg P ha-1 while the minimum harvest index (36.3%) was achieved in control plots.

Phosphorus source

In experiment 2, it was indicated that various phosphatic fertilizers had significant effect on biological yield and harvest index of wheat crop. Among the different phosphorus fertilizers SSP application had produced the highest biological yield and harvest index which was similar to TSP and NP while DAP produced lowest yield which possibly because of high availability of P, which contribute in early root and growth development. Khan et al. (2010) reported that SSP application performed better in term of productivity as compared to other P sources (DAP, TSP and NP). Reddy and Sigh (2003) also reported that SSP produced higher crop yield followed by by NP and DAP.SSP treted plot higher yield as compared with NP and DAP, which passibly  the additional affect of Sulphur which improved P availability to plants in SSP Ali et al. (2015).

Phosphorus and beneficial microbes interaction

The increase in BY due to application of BM probably the release of maximum plant nutrients from organic sources of soil especially P, higher photosynthetic rate (Xu et al. 2001; Sangakkara and Weerasikara. 2001). Amanullah et al. (2014) reported that application of  beneficial microbes improved spikes m-2 and grains spike-1 that produced higher biological yield. Because beneficial microbes application improve plant nutrients availability, especially of  P which produced higher growth and production (Soylu et al.  2004; Afzal et al. 2005; Tripura et al. 2005; Walpola and Yoon 2012). PSB + FYM along with P levels improved root developement, tillaering  and plant dry weight (Zhang et al., 1996). Application of the highest BM level improved yield and yield components (Amanullah et al., 2014) and thereby increased harvest index in wheat. Dobblaere et al. (2002) reported that wheat growth can be improved by application of BM, which increase grain spike-1 and grain yield-1. Khan et al. (2010) also reported that increase in grain yield increase the harvest index. According to Chaturvedi (2006) phosphate-solubilizing bacteria and FYM application increase wheat plant height, tiller m-2, leaf weight, grain yield, P, N and P uptake.

Phosphorus and zinc interaction

In the current study P x Zn interaction was found significant which showed that biomass yield increase with the increase in the levels of both nutrients. Arshad et al. (2016) reported that higher biomass was produced by P application at the rate of 90 kg ha-1 combine with 10 kg Zn ha-1 Jan et al. (2013).  Apllication of 90 kg P ha-1was applied produced higher biomass of wheat. Similar results was also reported by Potarzycki and Grzebisz (2009). Alam et al. (2005)  aslo repsorted that P application increase dry matter yield of wheat crop.

The interaction between Zn and P was studied earlier by many scientists, however, many results were inconsistent (Orabi et al. 1985). Shang and Bates (1987) found that P increased Zn deficiency in corn without Zn treatments, and Zn increased P deficiency in plants without P treatments, however, deficiency may be recover with the application of suitable nutrient. P combine with Zn and forming water non soluble zinc-phosphate compounds in soil solutions, which decrease the uptake of Zn by the plant roots and Zn translocation in the plant plant (Robson and Pitman, 1983); Kizilgoz and Sakin (2013). Burleson et al. , (1961; Zhao et al., (2007); Kacar and Katkat (2011)  the all reported that application of P increase P uptake by the plant but decreae Zn upatke by the plant which causing difeciency of Zn. In calcareous soils P application increased adsorption of Zn and calcium carbonate which are responsible for adsorption of Zn (Sead 2004). Li et al., (2003) reported that P application increase plant dry matter and P contents.

CONCLUSION

We concluded from our two years research that application of 100 kg P ha-1 + 15 kg Zn ha-1 along with beneficial microbes when applied at 20 days after emergence increased biological yield and harvest index (experiment one). In experiment two, the results showed that the higher biological yield and harvest index was obtained with application of an acidic P-fertilizer “single super phosphate” when applied at the highest P rate (120 kg P ha-1). among wheat varieties ranked first was Pirsabak-2013 by producing high yield and HI in the study area.

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