INTRODUCTION

Faba bean (Vicia faba) is a winter growing food legume crop. There are three main reasons for growing this crop, 1. Cash crop through marketing dry seeds, 2.  As a component of a rotation based on winter or summer cereals or cotton, and 3. Green manure where soils have been degraded in organic and physical fertility.

Nanotechnology can present solutions for increasing the value of agricultural products and reducing environmental problems. With using Nano-particles and Nano-powders, we can produce controlled or delayed releasing fertilizers. Nano-particles have high reactivity because of more specific surface area, more density of reactive areas, or increased reactivity of these areas on the particle surfaces. These features simplify the absorption of fertilizers and pesticides that produced in Nano scale (Anonymous, 2009). The use of nanofertilizers causes an increase in their efficiency, reduces soil toxicity, minimizes the potential negative effects associated with over dosage and reduces the frequency of application. Nanofertilizers mainly delay the release of the nutrients and extend the fertilizer effect period. Obviously, there is an opportunity for nanotechnology to have a significant influence on energy, the economy and the environment, by improving fertilizers. Hence, nanotechnology has a high potential for achieving sustainable agriculture, especially in developing countries (Naderi and Danesh-Shahraki, 2013).Furthermore, it is known that under nutrient limitation, crops secrete carbonaceous compounds into rhizosphere to enable biotic mineralization of N and/or P from soil organic matter and of P associated with soil inorganic colloids. Since, these root exudates can be considered as environmental signals and be selected to prepare nanobiosensors that will be incorporated into novel Nano fertilizers (Al-Amin Sadek and Jayasuriya, 2007, Sultan et al., 2009).

 Synthesized nanoparticle size ranged between 15 and 25 nm caused a significant improvement in shoot length (15.1 %), root length (4.2 %), root area (24.2 %), chlorophyll content (24.4 %), total soluble leaf protein (38.7 %), plant dry biomass (12.5 %), and enzyme activities of acid phosphatase (76.9 %), alkaline phosphatase (61.7 %), phytase (322.2 %), and dehydrogenase (21 %) were observed over control in 6 weeks old plants. The grain yield at crop maturity was improved by 37.7 % due to application of zinc nanofertilizer (Tarafdar  et al., 2014).Maximum production of maize was recorded for normal irrigation as 7 day irrigation period and application of nano- Zn nutrient and nanobiofertilizer nutrient, while severe water stress without application of nano- Zn nutrient and nano-biofertilizer produced minimum production (Farnia and Omidi, 2015). Synthesized nano-practices SNPs, significantly, enhanced most of the growth and yield attributes NPK uptake and nutrient use efficiency of wheat. Silver nanoparticles in 25 mg/L concentration showed significant improvement in maximum leaf area and highest grain yield of wheat) Jhanzab et al., 2015).The maximum plant height, Leaf fresh and dry weights, number of leaves per plant, and Chlorophyll content were gained with nano Zn chelated fertilizer treatment at rate of 100 mg on 600 liters water. Minimum plant height, leaf fresh and dry weight, number of leaves per plant, and chlorophyll content were obtained with control treatment (without fertilizer) (Vafa et al., 2015).

The main objective of this study was to investigate the response of some faba bean (Vicia faba L.) cultivars to mineral and nano-fertilizer and their interaction.

MATERIALS AND METHODS

Two filed experiments were conducted at Nubaria Agriculture Research Station, Alexandria, Egypt, during the growing seasons of 2014/2015 and 2015/2016 to study the effect of foliar mineral and Nano fertilizers on growth and yield of three faba bean cultivars under Nubaria conditions.

Treatments were arranged in a split plot design with three replications during both growing seasons of study. Whereas, the main plots were designated for foliar fertilizer (Nano fertilizer at vegetative stage, Nano fertilizer at flowering stage, Nano fertilizer at seeds filling stage. Nano fertilizer at (vegetative + flowering) stages, Nano fertilizer at (vegetative + filling), Nano fertilizer at (flowering + seeds filling) stages, Nano fertilizer at (vegetative + flowing + seeds filling) stages, and Mineral (NPK + Micronutrients), while subplot was alocated for three faba bean cultivars (Nubaria 1, Nubaria 2 and Nubaria 3)

Nano-fertilizer (8% Total N, 5 % total P, 3% total K, 10% micronutrients, 5% Amino acids and 5% Seaweed extract) at rate of 1 cm³/fed., and Mineral fertilizer (10 % N, 8% P, 5% K and 10% micronutrients) at rate of 0.5 litter/fed. used as foliar application.

A representative soil sample (0-30 cm) was taken before planting to determine some physical and nutritional properties of the experimental site (Page et al., 1982) and are presented in Table (1).

Table (1). Some soil properties of the experimental sites at Nubaria in 2014/2015 and 2015/2016 seasons

The preceeding crop in the experimental site was Egyptian clover (Trifolium alexandrinum, L.) in the first season and wheat (Triticum aestivum, L.) in the second season. Each sub plot consisted of 6 ridges, 3 meters in length, 60 cm width and 20 cm between hills.

The field experiment was ploughed twice then it was fertilized by phosphorus fertilizer before planting as single Calcium- Super Phosphate (15.5 % P₂O₅) at the rate of 200 kg/fed., and potassium sulphate (48 % K₂O), was added at rate of 50 kg/fed., before planting with soil preparation. Other agricultural practices for growing faba bean plants were applied as recommendation by Ministry of Agriculture.

Plant height (cm), total chlorophyll content (µg/cm²), pod length (cm), number of pods/plant, number of seeds/pod, 100- seed weight (g), seed yield (kg/fed.), straw yield (kg/fed.), biological yield (kg/fed.), and harvest index (HI) were recorded in both seasons.

The chlorophyll pigments were measured by using digital reading of chlorophyll meter SPAD-502, where the value measured by the chlorophyll present in the plant leaf. The values are calculated based on the amount of light transmitted by the leaf in two wave lengths in which the absorbance of chlorophyll is different. Total chlorophyll was determined by digital apparatus (SPAD-502) according to Murillo-Amador et al. (2004) who suggested the following equation to transfer SPAD units to µg cm^-2.

Y = –2.79 + 0.88 * X ; Where, X= SPAD units

All data collected were subjected to analysis of variance according to Gomez and Gomez (1984). All statistical analysis was performed using analysis of variance technique by means of CoStat computer software package(CoStat, Ver. 6.311., 2005).

RESULTS AND DISCUSSION

Data in Tables (2, 3, 4, 5 and 6) indicates the effect of foliar application of Nano and mineral fertilization on some growth attributes such as plant height (cm) and chlorophyll content (µg/cm²), yield and its component i.e. number of pods/plant, pod length (cm), number of seeds/pod, 100- seed weight (g), seed, straw, biological yields as well as harvest index (HI %) of three faba bean cultivars  (Nubaria1, Nubaria 2, and Nubaria3) at different growth stages (vegetative, flowering and filling) and their interaction during 2014/2015 and 2015/2016 seasons.

The presented data in above mentioned Tables (2 to 6) show that foliar application of nano and mineral fertilization, significantly, affected these characters in both cropping seasons.

Table (2) reveal that, the highest mean values of plant height (cm) were recorded with foliar application of nanofertilization in both growth stages (vegetative and filling) followed by foliar nanofertilization at the three growth stages (vegetative, flowering and seeds filling) and at the two stages (vegetative and flowering) of faba bean as compared with other treatments but the highest concentration of chlorophyll (µg/cm²) was achieved by nanofertilizer spraying at stages (flowering and seeds filling) as compared with other treatments.  Meanwhile, the lowest ones were recorded with foliar nano- fertilization in vegetative stage of faba bean during two cropping seasons. These results are in agreement with who that obtained by Karimia et al. (2014), Tarafdar et al. (2014) and Vafa et al. (2015) stated maximum plant height and chlorophyll content gained from Nano fertilizer treatment and lowest value of plant height was related to the treatment without nanofertilizer (check treatment). Also, data in Table (2) indicate that, the faba bean cultivar “Nubaria 2” recorded the tallest plants height and highest value of chlorophyll concentration (µg/cm²), while "Nubaria 1” cultivar gave the lowest ones in both growing seasons. On the other hand, there was no significant difference between “Nubaria1” and “Nubaria 3” cultivar on plant height in the first season and on chlorophyll content during the two seasons. These differences between field bean are mainly due to genetical differences make up between the three cultivars. These results are in harmony with those obtained by Nosser (2011), Hendawey and Younes (2013), and Kandil et al. (2015). In Table (2) foliar application of nanofertilization in both stages (vegetative and filling) with “Nubaria 2” cultivar gave the tallest plants in the first season and it recorded the highest concentration of chlorophyll (µg/cm²) in both seasons. Meanwhile the lowest ones were achieved by foliar nano fertilization at vegetative stage of “Nubaria 1” cultivar.

Table (3) indicate that, the highest mean values of number of pods/plant and pod length (cm) were recorded with foliar application of nanofertilization in both stages (vegetative and seeds filling) followed by foliar nanofertilization at the three stages (vegetative, flowering and filling) and at the two stages vegetative and flowering of faba bean as compared with other treatments.  Meanwhile, the lowest ones were recorded with foliar nano- fertilization in vegetative stage of faba bean during the two cropping seasons. These results are in agreement with those obtained by Nosser (2011), and Nazanin et al. (2013). Again Table (3) clarify that the faba bean “Nubaria 2” cultivar gave the highest values for number of pods/plant and pod length (cm), on the other hand, "Nubaria 1” cultivar recorded the lowest ones in the two growing seasons. On the other side, there was no significant difference between “Nubaria1” and “Nubaria 3” cultivar on pod length in the first and second season. These results are in harmony with those obtained by Turk and Tawaha (2001), Khafaga et al. (2009), Osman et al. (2010). At last Table (3) reveal that, interact of foliar application of nanofertilization in both stages (vegetative and seeds filling) with “Nubaria 2” cultivar achieved the highest number of pods/plant and pod length (cm). Meanwhile the lowest ones were achieved by foliar nano fertilization at vegetative stage “Nubaria 1” cultivar.

Table (4) shows that, the highest mean values for number of seeds/pod (5.00 and 4.44 seeds) and 100- seed weight (95.82 and 98.33 g), respectively, were recorded with nanofertilization in stages (vegetative and seeds filling) as compared with other treatments.  Meanwhile, the lowest ones were recorded for nano- fertilization in vegetative stage of faba bean during the two cropping seasons. These results are in agreement with those obtained by Nosser (2011), Nazanin et al. (2013). On the other hand, Table (4) reported that the faba bean “Nubaria 2” cultivar gave the highest values for number of seeds/pod (4.67 and 5.41 pods) and 100- seed weight (97.47 and 98.92 g), respectively, while, the lowest ones were achieved by planting "Nubaria 1” cultivar in the two growing seasons. On the other side, there was no significant difference between “Nubaria1” and “Nubaria 3” cultivar for seeds number/pod in the first and second seasons, and only in the second season for 100- seed weight (g). These results are in harmony with those obtained by Khafaga et al. (2009), and Osman et al. (2010). Interaction effect as shown in Table (4) show that, fertilizing “Nubaria 2” by nano- fertilizer as foliar spraying in (vegetative and filling) stages gave the highest number of seeds/pod but the heaviest 100- seed weight were recorded by fertilizing “Nubaria 2” by nano- fertilizer at (flowering and seeds filling) stages. Meanwhile fertilizing “Nubaria 1” by nano- fertilizer at (vegetative) stage achieved the lowest ones.

Table (5) show that, the highest mean values for seed yield (1693.93 and 1679.67 kg/fed) were recorded for nanofertilization in (vegetative and seeds filling) stages as compared with the other treatments but the heaviest straw yield (2479.82 and 2477.18 kg/fed.) were achieved by fertilizing faba bean plants by nano- fertilizer as foliar application at vegetative, flowering and seeds filling stages in both seasons.  Meanwhile, the lowest seed yield (1000.78 and 992.55 kg/fed.) were recorded with nano- fertilization in vegetative stage of faba bean during the two cropping seasons, while the lowest straw yield was achieved by nano- fertilizer application at flowering stage. These findings are in agreement with those obtained by Nosser (2011), and Nazanin et al. (2013). Table (5) again, referred that the faba bean “Nubaria 2” cultivar gave the highest values for number of seeds/pod (4.67 and 5.41 pods) and 100- seed weight (97.47 and 98.92 g), respectively, while, the lowest ones achieved  by planting "Nubaria 1” cultivar in the two growing seasons. On the other side, there was no significant difference between “Nubaria1” and “Nubaria 3” cultivar on straw yield/fed., in the first and second seasons. These results are in harmony with those obtained by Khafaga et al. (2009), and Osman et al. (2010). Interaction effect as shown in Table (5) indicate that, fertilizing “Nubaria 2” by nano- fertilizer as foliar spray in (vegetative and seeds filling) stages gave the highest seed yield/fed., and straw yield/fed. Meanwhile fertilizing “Nubaria 1” by nano- fertilizer at (vegetative) stage achieved the lowest ones.

Table (6) reveal that, the highest mean values for biological yield (3807.59 and 3792.62 kg/fed) were recorded for nanofertilization in (vegetative, flowering and seeds filling) stages as compared with other treatments but the highest HI % (46.08 and 45.75) were achieved by fertilizing faba bean plants by nano- fertilizer as foliar application at vegetative, and seeds filling stages in both seasons, respectively.  Meanwhile, the lowest biological yield (2613.79 and 2619.76 kg/fed.) and HI (37.82 and 37.20 %) were recorded for nano- fertilization in vegetative stage or mineral fertilizer of faba bean during the two cropping seasons, respectively. These findings are in agreement with those obtained by Nosser (2011), and Nazanin et al. (2013). Table (6) again, indicated that the faba bean “Nubaria 2” cultivar gave the highest values for biological yield (3650.83 and 3678.65 kg/fed.) respectively, in respect of HI %, there was significant difference among the three cultivars only in the second season. Meanwhile, the lowest ones were achieved by planting "Nubaria 1” cultivar in the two growing seasons. On the other side, there was no significant difference between “Nubaria1” and “Nubaria 3” cultivar on straw yield/fed., in the first and second seasons. These results are in agreement with those obtained by Khafaga et al. (2009), and Osman et al. (2010). Interaction effect between the two was significant, whereas fertilizing “Nubaria 2” cultivar by nano- fertilizer as foliar spray in (vegetative and filling) stages gave the highest biological yield/fed., and HI %. Meanwhile fertilizing “Nubaria 1” by nano- fertilizer at vegetative stage achieved the lowest ones (Table 6).  

Table (2). Plant height (cm) and chlorophyll (µg/cm²) of three faba bean cultivars as influenced by foliar mineral and nanofertilizer and their interaction during 2014/2015 and 2015/2016 seasons.

-        Average  values in the same column/row marked with the same letters are not significantly different at 0.05 level of probability.

-        N.S.: not significant difference at 0.05 level of probability.

Table (3). Number of pods/plant and pod length (cm) of faba bean cultivars as influenced by foliar mineral and nanofertilizer and their interaction during 2014/2015 and 2015/2016 seasons

-        Average  values in the same column/row marked with the same letters are not significantly different at 0.05 level of probability.

-        N.S.: not significant difference at 0.05 level of probability.

Table (4). Number of seeds/pod and 100- seed weight (g) of faba bean cultivars as influenced by foliar mineral and nanofertilizer and their interaction during 2014/2015 and 2015/2016 seasons

-        Average values in the same column/row marked with the same letters are not significantly different at 0.05 level of probability.

-        N.S.: not significant difference at 0.05 level of probability.

Table (5). Seed and straw yields (kg/fed.) of faba bean cultivars as influenced by foliar mineral, nanofertilizer and their interaction during 2014/2015 and 2015/2016 seasons

-        Average  values in the same column/row marked with the same letters are not significantly different at 0.05 level of probability.

-        N.S.: not significant difference at 0.05 level of probability.

Table (6). Biological yield (kg/fed.) and harvest index % of faba bean cultivars as influenced by foliar mineral and nanofertilizer and their interaction during 2014/2015 and 2015/2016 seasons

-        Average  values in the same column/row marked with the same letters are not significantly different at 0.05 level of probability.

-        N.S.: not significant difference at 0.05 level of probability.