Influence of Varying Concentrations of Ammonium Sulphate Foliar Spray on Phenology and Yield of Canola

Rapeseed (Brassica napus L.) belongs to the Cruciferae family the common species are Nigra, Carinata, juncea, oleracea and compestries Holmes [1]. Rapeseed or mustard was grown from 300Bc in Indus valley of Pakistan as a fodder crop. Rapeseed and mustard are traditional oil seed crops of Pakistan are grown in large area of four provinces of country Khan et al. [2] Canola was introduced in Pakistan during 1995 for general cultivation to replace traditional oilseed crops like rapes and mustards because of its low erucic acid contents and high yielding capacity (Chaudhry et al. 2011). During 2011-12 in Pakistan the Canola crop was cultivated 14700 ha with the production of 7000 tones, while Khyber Phukhtunkhwa the area under cultivation was 1300 ha with a total production of 1800 tones MNFSR [3].


Introduction
Rapeseed (Brassica napus L.) belongs to the Cruciferae family the common species are Nigra, Carinata, juncea, oleracea and compestries Holmes [1]. Rapeseed or mustard was grown from 300Bc in Indus valley of Pakistan as a fodder crop. Rapeseed and mustard are traditional oil seed crops of Pakistan are grown in large area of four provinces of country Khan et al. [2] Canola was introduced in Pakistan during 1995 for general cultivation to replace traditional oilseed crops like rapes and mustards because of its low erucic acid contents and high yielding capacity (Chaudhry et al. 2011). During 2011-12 in Pakistan the Canola crop was cultivated 14700 ha with the production of 7000 tones, while Khyber Phukhtunkhwa the area under cultivation was 1300 ha with a total production of 1800 tones MNFSR [3].
Like all other crops, growth, developmental process and grain yield of canola depends upon biotic and abiotic factors. Sulfur is the fourth major plant nutrient after nitrogen, phosphorus and potassium. It is essential for synthesis of the amino acids like cystine, and methionine, a component of vitamin A and activates certain enzyme systems in plants Havlinet al. [4]. It is also an important soil fertility factor to consider when growing canola Ghosh et al. [5] because of high requirement of S by Cruciferae family Scherer [6]. The seed yield, total dry matter and harvest index in some genotypes of Brassica napus and Brassica juncea has been found to improve with higher rate of sulphur Chandel et al. [7] and Malhi et al. [8]. Sulphur deficiency adversely reduces yield, protein and enzyme synthesis Scherer [6]. Sometimes Plant immobility makes the nutrient deficient and S deficiency at any growth stage can cause considerable reduction in seed yield of canola and thus a regular supply of available S is required throughout the growing season Malhi and Gill [9].
available soil is almost nutrient deficient (Anon 2008). Soils are generally deficient in organic matter content reflecting the severe deficiency of nitrogen (almost 100 %) with phosphorus deficiency in more than 90 percent soils and potassium in 50 percent soils Anon [10]. Micronutrients; zinc, boron and iron are also emerging as deficient. Ahmad and Khan [11] declared that 75-92 percent soils of Pakistan are deficient in organic matter (0-1%), 70-95 percent in phosphates and 20-60 percent soils in potash. Keep in view the importance of ammonium sulphate present research was conducted in order to study the response of canola to different application of foliar spray on canola the objectives to determine the effects of ammonium sulphate (1%, 0.2%, and 0.3% ) foliar application on canola phenology and traits.

Materials and Methods
The Experiment entitled ''Phenological traits of canola in response to different concentrations of ammonium sulphate foliar spray" was conducted at the Palatoo research farm Department of Agronomy, Amir Muhammad khan Campus, Mardan during rabi season 2014-2015. The experiment consists of ammonium sulphate levels (1%, 0. 2% and 0.3%) and water spray. The experiment was laid out in randomized complete block, having four replications. The plot size was 2×2 m². Ploughing was done with help of cultivator and crop sown. The basel dose N and P @70 and 40kg 1 ha applied respectively. Hoeing was carried out after rosette stage to control weeds. All the agronomic practices were applied according to crop need (Table 1).

Statistical Analysis
The data recorded was analyzed statistically using analysis of variance techniques appropriate for randomized complete block design. Means were compared using LSD test at 0.05 level of probability, when the F-values were significant Sharifi et al. [12] and Malik et al. [13]. Data regarding number of leaves as influenced by different levels of Ammonium Sulfate foliar spray is presented in (Figure  1). Statistical analysis of the data had showed non-significant effect. However, the number of leaves generally increased with the increasing levels of Ammonium sulfate as foliar spray. The possible reason might be that it is genetically character which cannot be effected by external application of fertilization/ nutrients respectively. As the ammonium sulphate solution was applied to crop in very less concentration, therefore the number of leaves was not significantly affected. Number of branches per plant as influenced by different levels of Ammonium Sulfate foliar spray is presented in ( Figure  2). Analysis of the data had showed non-significant effect on branches per plant. However, the number of branches generally increased with the increasing levels of Ammonium sulfate as foliar spray. The possible reason might be that it is genetically character which cannot be effected by external application of fertilization/ nutrients respectively. As the ammonium sulphate solution was applied to crop in very less concentration, therefore the numbers of branches were not significantly affected.

Days to flowering
Data regarding days to flowering as influenced by different levels of Ammonium Sulfate foliar spray is presented in (Figure  3). Statistical Analysis of the data had showed significant effect on number of days taken to initiation of flowers formation. Maximum days to flower formation initiation (303) were noticed by the application of 1 % foliar application of Ammonium sulfate, followed by 0.3 % foliar spray (308) while minimum days to flowering (309) was recorded in plots with no spray. These findings are also in line with Brandt et al. [14].  Pods formation of canola as influenced by different levels of Ammonium Sulfate foliar spray is presented in (Figure 4). Statistical Analysis of the data had showed significant effect on number of days taken to pods formation. Maximum days to pods formation (350) were recorded by the application of 1 % foliar application of Ammonium sulfate, followed by 0.3 % (367), 0.2 % (371) while minimum days (372) were recorded in plots with no spray. These findings are also in line with Brandt et al. [14] and Nakhlaway et al. [15]. Number of days taken from sowing till the maturity of the crop as affected by different levels of Ammonium Sulfate foliar spray is given in (Figure 5). Based on statistical analysis of the data showed a significant effect on number of days taken to crop maturity. Maximum days to maturity (469) were observed for 1 % foliar application of Ammonium sulfate, followed by 0.3 % (471) which is statistically at par with 0.2 % spray while minimum days to maturity (484) were recorded in plots with no spray. These findings are also in line with Nakhlaway et al. [15] and Cheema et al. [16].

Days to maturity
Biological yield (kg ha -1 ) Figure 6: Biological yield (kg ha -1 ) of Canola as affected by different levels of ammonium sulphate foliar application.
Data regarding on biological yield is presented in ( Figure  6). Statistical analysis shows that there is a significant effect on biological yield of canola due to ammonium sulphate foliar application. Maximum biological yield (3856kgha -1 ) were obtained with the application of 1% ammonium sulphate as compare to control (2726 kgha -1 ), 0.2% (1568 kgha -1 ) and 0.3% (3233 kgha -1 ) solution. The result are in line with the findings of Malik et al. [13] and Jan et al. [17] and Sattar et al. [18] who found that from higher rate of sulphur application more biological yield can be obtained [19][20][21][22][23][24][25].
Grain yield (kg ha -1 ) Grain yield kg ha-1 of canola as affected by ammonium sulfate foliar spray is presented in (Figure 7). Statistical analysis shows that there is a significant affect in grain yield due to ammonium sulphate foliar application on canola [26]. More grain yield (2360 kgha -1 ) were obtained with the application of 1% ammonium sulphate as compare to control (2147 kgha-1), 0.2% (1700 kgha -1 ) and 0.3%(2323 kgha -1 ) solution [27][28][29]. The result is also in agreement with the findings of Sharifi [12] who reported that increasing levels of sulphur solution increased grains yield of canola which is an oil seed crop, respond positively to sulphur application due to which its grain yield increases Malik et al. [13].

Conclusion and Recommendation
From this experiment it was concluded that number of leaves and branches were not affected by ammonium sulphate foliar spray while less days to flowering (303), days to pod formation (350), days to maturity (469), more biological yield (3856 kg ha -1 ) and grain yield (2360 kg ha -1 ) were recorded for 1% foliar application of sulphur. On the basis of current research it is recommended that ammonium sulphate @ 1% foliar spray is optimum for achieving phenological attributes and yield of canola.