Effects of zinc and nitrogen fertilizer and their application method on yield and yield components of Phaseolus vulgaris L. ()
1. INTRODUCTION
Phaseolus vulgaris L. is one of the most important leguminous crops for exportation and consumption [1]. Nitrogen (N) fertilizer played a significant role in increase of crop yield [2]. Nitrogen deficiency generally results in stunted growth and chlorotic leaves caused by poor assimilate formation that leads to premature flowering and shortening of the growth cycle [3]. Limitation of nitrogen in any phase of the plant growth, causes reduction in yield [4]. Abdzad Gohari and Amiri was reported that nitrogen fertilization had a positive and significant effect on seed yield, seed weight, number of pods per plant and number of seeds per plant [5].
Seventy years ago, zinc was recognized as an essential micronutrient [6], and its deficiency in agricultural crops is one of the most common micronutrient deficiencies [7]. Zinc deficient soils have been widely found in India, USA, Canada, New Zealand, Africa, Europe and South America [8]. On the other hand, World Health Organization (WHO) reported that human population of developing countries faced with the deficiencies of zinc. Zn deficiency of human is the fifth major cause of diseases and deaths in these countries [9]. Foliar fertilization has the advantage of low application rates, uniform distribution of fertilizer materials and quick responses to applied nutrients. Moreover, hidden hungers can easily be managed [10]. Mahady [11] found that foliar application of ZnSO4 for faba bean plants increased number of pods/plant and seed yield. Ali and Mowafy reported that application of foliar spray with Zn (2%) slightly improved groundnut yield and it’s attributed as well as quality [12]. Thalooth et al. indicated that foliar spraying with Zn had a positive effect on yield and yield attributes of sunflower plants [13,14].
The aim of the study is to investigate the influences of zinc spray and different amounts of nitrogen fertilizer on yield and the yield components of Phaseolus vulgaris L.
2. MATERIALS AND METHODS
In order to investigation of zinc spray and nitrogen fertilizer on yield and yield components of Phaseolus vulgaris L. an experiment in factorial format based on randomized complete block design with 3 replications. Soil analysis results show that (Table 1), the soil texture was loam clay and pH 7.3. Factors of experiment was included two levels of zinc spraying (z1: without zinc spraying, z2: zinc spraying 1 g/L) and nitrogen fertilizer (n1: control (without nitrogen fertilizer application), n2: 25, n3: 50 and n4: 75 kg/ha pure nitrogen). Pure nitrogen was prepared from urea (46% pure nitrogen). Zinc spraying was done in two stages vegetative stage (35 days after sowing) and flowering period. Measured traits were seed yield, seed weight, number of pods per plant, number of seeds per pod and plant height. The data was analyzed using MSTATC software. The Duncan’s multiple range tests (DMRT) was used to compare the means at 5% of significant.
3. RESULTS AND DISCUSSION
Results of variance analysis (Table 2) showed that, the effect of zinc spraying on all measured traits had significant differences in 1% probability level. In all studied traits observed that, use of zinc spraying had an optimum effect on bean characteristics. Comparison of mean showed that the highest seed yield with 1996.1 kg/ha, 100 seed weight with 43.9 g, number of pods per plant with 7.8, number of seeds per plant with 5.7 and plant height with 84.7 cm was obtained by zinc spraying (Table 3). The lowest seed yield, 100 seed weight, number of pods per plant, number of seeds per pod and plant height respectively with 1730.6 kg/ha, 42.2 g, 7.1, 4.8 and 83 cm was found from without use of zinc spraying. Similar results were reported by Khampariva, Agrawal et al. and Togay et al. [15-17].
With attention to variance analysis results, the effect of nitrogen fertilizer doses on all studied traits was significant in 1% probability level. Comparison of mean between nitrogen fertilizer levels (Table 3) show that, the highest seed yield, 100 seed weight, number of pods per plant, number of seed per pod and plant height was ob-
Table 1. Soil analysis results of the experimental sites.
Table 2. Analysis of variance related to the traits of pinto bean under different levels of zinc spraying and nitrogen fertilizer.
Table 3. comparison of the mean of the effects zinc spraying and nitrogen fertilizer.
tained by 75 kg/ha pure nitrogen respectively with 2724 kg/ha, 44.54 g, 8.041, 6.11 and 88.28 cm. the n3 level (50 kg/ha pure nitrogen) with 44.30 gram 100 seed weight placed in same statistically level with n4 treatment (75 kg/ha pure nitrogen). In the other hand the lowest seed yield with 933.2 kg/ha, 100 seed weight with 39.60 g, number of pods per plant with 7.11, number of seeds per pod with 4.53 and plant height with 81.08 cm was found from n1 treatment (without nitrogen fertilizer application). Similar results were reported by Geetha and Varughese, Mirjana et al. and Abdzad Gohari et al. [18-20].
Interaction effect of zinc spraying and nitrogen fertilizer on number of pods per plant in 1% and on seed yield and plant height in 5% probability level was significant. But had not any significant effect on 100 seed weight and number of seeds per pod (Table 2). The highest seed yield with 2771 kg/ha, plant height with 88.45 cm and number of pods per plant with 8.57 was obtained by use of zinc spraying and 75 kg/ha pure nitrogen application (Figures 1-3). On the other hand, the lowest seed yield with 747.3 kg/ha, plant height with 79.4 cm and number of pods per plant with 6.95 was found from z1n1 treat-
Figure 1. interaction effect of zinc spraying and nitrogen fertilizer levels on seed yield.
Figure 2. interaction effect of zinc spraying and nitrogen fertilizer levels on plant height.
Figure 3. interaction effect of zinc spraying and nitrogen fertilizer levels on number of pod per plant.
ment (without zinc spraying and no nitrogen fertilizer application). Similar results were obtained by other researcher [20-22].