Effect of humic acid and zinc sulphate on growth and yield of French bean (Phaseolus vulgaris L.)

Introduction

French bean (Phaseolus vulgaris L.), commonly called kidney bean, haricot bean or snap bean is a member of the family Leguminosae. It is a self -pollinated annual plant (Cobley et al., 1976). It is a short duration crop having an average lifespan of 65-110 days from emergence to physiological maturity (Buruchara, 2007) [6] . French bean (Phaseolus vulgaris L.) was introduced in India during the 17 th century from Europe (Simmonds, 1976) [9] . The primary center of origin is accepted to be Mexico and Central America while the Peruvian Ecuadorian area is considered to be a secondary center (Evans, 1976) [9] . French bean is largely grown in hilly areas of Himachal Pradesh, Jammu-Kashmir and northeastern states during summer, and in parts of Uttar Pradesh, Maharashtra, Karnataka and Andhra Pradesh it is grown in winter and autumn. In northern plains, it is cultivated on a limited scale as autumn or spring crop. Immature tender pods generally consumed as green vegetables and dry seeds as pulse. It is a rich source of vegetable proteins as compared to other vegetables. It also contains dietary fiber, and complex carbohydrates and also provides folic acid. Per 100 gm of edible part contains 4.5% carbohydrates, 1.7% proteins, 0.1% fat, 221 IU vitamin A and 0.5% minerals. It is also known to have anti-diabetic properties and good for dropsy, dysentery, eczema, emollient, hiccups, itch, bladder burns, cardiac and kidney related issues. It is carminative, depurative, and diuretic (Duke, 1981) [8] . Fresh market cultivars are often flat or oval-shaped while for processing, round podded varieties are recommended.

The extraction of humic acid is done from different sources such as coal, peat, humus, soil, and oxidized lignite. Humic acid have positive influence on the growth of shoots and roots and the absorption of nitrogen, potassium, calcium, magnesium, and phosphorus by plants. Moreover, its important role for the improvement of growth, production, and quality of agricultural products is due to the presence of hormonal compounds (Abdel-Mawgoud et al. 2007) [1] . Being a vital component of soil organic matter, it improves physico-chemical characteristics of soil like particle aggregation, water permeability, soil aeration, water holding capacity, ion exchange, and also enhances soil fertility through increased availability of nutrients through pH buffering (Tan, 2003) [16] . Humic acid had been reported to improve soil health through reduction of soil-borne diseases (Mauromicale et al. 2011) [13] . The micronutrients are essential for normal plant growth. The adverse effect of their deficiency in plants on the growth, metabolism, and reproductive phase. Zinc plays an important role in protein and chlorophyll synthesis as well as nucleic acid. Being a constituent of tryptophan, a precursor of auxin, it also helps in auxin synthesis (Hafeez et al. 2013) [10] . It activates the functions of many enzymes such as aldolases, and transphosphorylases and enhances various physiological processes like cell division, protein synthesis, and maintenance of membrane structure (Andreini et al. 2006, Broadley et al. 2007, and Marschner, 2012) [3,5,12] . It promotes biosynthesis of growth hormone, and formation of starch apart from its positive role on seed production and its maturation (Brady and Weil, 2002) [4] . The nutrient requirement generally depends upon the crop, cultivar, soil, and various environmental factors. Therefore, it was felt necessary to undertake a location-specific trial for french bean to determine its requirement of humic acid and zinc considering its growth and yield prospect in the lateritic belt of the Birbhum district of West Bengal having suitable agroclimate during the winter season.

Materials and Methods

The field experiment was conducted at the Horticultural Farm, Department of Horticulture and Post-Harvest Technology, Palli-Sikshsa Bhavana (Institute of Agriculture), Visva-Bharati, West Bengal from November 2021 to March 2022. The experimental site was present in the red and lateritic zone of West Bengal at 23 0 42" N latitude and 87 0 30" E longitude. During the crop growth period (25 Nov.2021 to 10 March 2022) the minimum and maximum tempt. Ranged from 10.23 to 31.33 respectively. The average RH range was 60.14 -87.14. The average bright sunshine hours per day ranged from 2.04 hours to 9.41 hours. The total rainfall received during the cropping period was 19.14 mm The experimental design was laid out in factorial randomized block design with three replications and nine treatments. The size of the individual plot was 2.5 m in length and 2 m in width (2.5 × 2 m) and the whole area was intercepted by an irrigation cum drainage channel of 50 cm. The bund beside the channel was 15 cm and the intra-replication bund was 30 cm. The details of experiment, treatments and layout have been in table1 and table 2 respectively. No humic acid + Zinc sulphate @ 1% T4 HA1Zn0 Humic acid @ 10 kg/ha + No zinc sulphate T5 HA1Zn1 Humic acid @ 10 kg/ha + Zinc sulphate @ 0.75% T6 HA1Zn2 Humic acid @ 10 kg/ha + Zinc sulphate @ 1% T7 HA2Zn0 Humic acid @ 15 kg/ha + No zinc sulphate T8 HA2Zn1 Humic acid @ 15 kg/ha + Zinc sulphate @ 0.75% T9 HA2Zn2 Humic acid @ 15 kg/ha + Zinc sulphate @ 1% Note: HA0 = No humic acid, HA1= 10 kg/ha, HA2 = 15 kg/ha, Zn0 = No zinc, Zn1 = 0.75%, Zn2 = 1%

The land was prepared by repeated ploughing and harrowing to obtain fine tilth. Then the land was divided into 27 small plots having a dimension of 2.5 × 2 m. Well-decomposed farm yard manure (FYM) was applied @ 25 tones/ha during the preparation of the plots. According to the treatment, the required amount of nitrogen was applied @ 60 kg/ha in 2 split doses (1/2 part as basal dose and remaining half as top dressing after 40 days of sowing) and the total amount of phosphorus @ 50 kg/ha and potassium @ 70 kg/ha was applied as basal. All the three nutrients i.e., nitrogen, phosphorus and potash were applied in the form of urea, single super phosphate and muriate of potash, respectively. Seeds were treated with rhizobium culture (Sabour Rhizo) @ 4-6 ml/kg of seed. The culture was collected from Bihar Agricultural University, Sabour, Bhagalpur.

Results and Discussions

T+he results obtained under the experiment entitled "Effect of humic acid and zinc sulphate on growth and yield of French bean (Phaseolus vulgaris L.)" in lateritic soil of Birbhum, West Bengal were analyzed and presented thoroughly with the help of different tables.

Growth and flowering parameters

Growth of the French bean was studied with respect to plant height, number of branch er plant, and number of days taken to first flowering, fifty percent flowering, and 100% percent flowering.

Data presented in table 3 showed variable effects of humic acid on plant height observed at 40 days, 55 days and 70 days. The maximum height (52.4 cm) was achieved in HA 1 (10kg/ha) after 70 days, though, it was reduced at higher level (HA 2 ). Minimum plant height (51.5 cm) was observed in HA 0 (control). But overall the effects shown was not significant and minor increase in height is observed. The perusal of data indicated that plant height measured at final stage (i.e.70 DAS) was not influenced markedly by the application of different levels of zinc, though, numerical increase in plant height was observed. Maximum plant height (53.3 cm) was recorded at 70 days with foliar application of zinc sulphate at 1% (Zn 2 ), while minimum value in this regard (51.4 cm) was observed with with Zn 1 (0.75%). The interaction between humic acid and zinc did not show remarkable effect on the plant height. The maximum plant height (53.9 cm) was recorded under combined application of humic acid (10 kg/ha) and zinc (1%) in HA 1 Zn 2 . The minimum plant height (49.4 cm) was recorded in the HA 0 Zn 1 . The enhanced effects due to interaction of zinc and humic acid were in conformity with findings of Yilmaz et al. (2013) [17] .

Number of branch per plant

The number of branch per plant recorded in different growth stages as influenced by the different levels of humic acid and zinc and their interaction are presented in Table 4. It was evident from the results, that the application of humic acid failed to influence the number of branch per plant markedly, though, numerical increment in the value in dose dependent manner was evident. The highest number of branch (9.5) was observed when HA 2 (15 kg/ha) was applied, and lowest value in this regard was recorded in HA 0 (control). The response of the plant to zinc application exhibited the similar trend. However, application at its highest level in Zn 2 (1%) resulted the highest number of branch per plant (9.6). The lowest number of branch (9.2) was observed in Zn 1 (0.75%). The combined application of humic acid and zinc did not show any remarkable effect on number of branch of French bean. However, application of HA 0 Zn 2 resulted highest number of branch per plant (9.9). On the other hand, the lowest number of branch per plant (8.8) was observed at HA 0 Zn 1 . Similar trend in number of branch per plant was also reported by Doddamani et al., (2020) [7] . The results for number of days to first flowering as influenced by different levels of humic acid and zinc sulphate and their combination were presented in Table 5. Analysis of results indicated that application of various levels of humic acid failed to exert any significant influence on number of days to first flowering. However, reduction in number of days to first flowering was observed at moderate level of humic acid (HA 1 @ 10 kg/ha), though, it was mere numerical. Application of zinc could not influence the number of days to first flowering, though, maximum delay in first flowering (47.1) was observed with moderate level of applied zinc (Zn 1 ) and the minimum value for the same (46.0) was recorded in control (Zn 0 ). The interaction between humic acid and zinc sulphate did not show any remarkable effect on number of days to first flowering. The minimum number of days to first flowering (45.7) was recorded under combined application in HA 1 Zn 0 . However, maximum number of days to first flowering (47.3) was recorded in HA 1 Zn 1 .

Number of days to 50 % flowering

The results on number of days to 50% flowering as influenced by different levels of humic acid and zinc sulphate and their combination were presented in Table 5. The recorded data indicated that application of various levels of humic acid had failed to show any remarkable effects on number of days to 50% flowering. The maximum number of days to 50% flowering (50.1) was observed with moderate level of applied humic acid (10 kg/ha) and the minimum value in this regard (49.4) was recorded in control (HA 0 ). Perusal of data indicated that application of zinc significantly influenced the number of days to 50% flowering. Remarkable earliness with respect to number of days to 50% flowering (48.9) was observed with non-application of zinc in control plots. On the other hand, maximum delay with respect to number of days to 50% flowering (50.4) was observed with medium level of applied of zinc in Zn 1 (10 kg/ha). The interaction between humic acid and zinc sulphate could not influence the number of days to 50 % flowering markedly. The lowest number of days to 50% flowering (48.3) was recorded in control plots (HA 0 Zn 0 ) followed by HA 2 Zn 0 , HA 1 Zn 0 , HA 1 Zn 2 . However, maximum number of days to 50% flowering (51.3) was recorded in HA 1 Zn 1 .

Number of days to 100 % flowering

The results number of days to 100% flowering as influenced by different levels of humic acid and zinc sulphate and their combination were presented in Table 5. The analysis data indicated that application of various levels of humic acid failed to show any remarkable effects on number of days to 100% flowering. However, numerical decrease in number of days to 100% flowering (52.9) was recorded in control plots and the maximum value in this regard (54.0) was noted where humic acid was applied at the rate of 10 kg/h delay (HA 1 ). Moreover, failure to influence the number of days to 100% flowering with any statistical significance was observed with application of zinc. However, numerical increase in number of days to 100% flowering (53.8) was observed with moderate level of applied zinc (10 kg/h) in Zn 1 and the minimum value for the same (52.2) was recorded in control (Zn 0 ). It was also noted that combined application of humic acid and zinc sulphate could not show any remarkable influence on number of days to 100% flowering. The lowest number of days to 100% flowering was recorded under combined application in HA 2 Zn 0 followed by HA 0 Zn 0 , and HA 0 Zn 1 . However, maximum number of days to 100% flowering (55.3) was recorded in HA 1 Zn 1 .

Yield parameters

Yield attributes and yield of French bean was studied with respect to number of pod per plant, pod yield per plant, pod yield per plot, and pod yield per hectare.

Average pod weight

Data regarding average pod weight was analyzed and presented in the Table 6.

The response of the plant towards humic acid had failed to influence the average pod weight significantly. However, the maximum pod weight (5.4 g) was observed in HA 0 (control), and minimum value (5.1 g) was recorded in HA 2 .

A critical examination of data indicated that various level of zinc sulphate could not influenced the average pod weight markedly.

The highest pod weight (5.4 g) was noted in Zn 0 , and lowest value in this regard (5.1 g) was observed in Zn 1 . On other hand, combined application of humic acid and zinc sulphate did not influence the average pod weight significantly. However, the lowest average pod weight (4.9 g) was recorded under combined application in HA 0 Zn 1 and HA 2 Zn 2 , while highest average pod weight (5.7g) was recorded in HA 0 Zn 0 (control). This was found to be contradictory to findings of Karakurt et al., 2012 [11] .

Average pod yield per plant (g) Observation recorded on average pod weight per plant were statically analyzed and presented in the table7.

The data revealed that average pod weight per plant did not differ significantly with different levels of humic acid. However, maximum average pod weight per plant (106.7 g) was observed in HA 0 (control) and minimum value (94.0 g) in HA 1 .

The response of the plant to zinc application exhibited the similar trend on the pod weight per plant. However, maximum average pod weight per plant (111.0 g) was observed in Zn 0 (control) and minimum value in this regard (92.0 g) was observed in Zn 1 .

The data in the table also revealed that combined application of humic acid and zinc sulphate failed to show marked effect on average pod weight per plant. The lowest average pod weight per plant (89.4 g) was recorded under combined application HA 2 Zn 1 , while highest average pod weight per plant (122.2 g) was recorded in HA 0 Zn 0 (control).

In previous discussion it was already revealed that variation of average pod weight per plant with the application of humic acid and zinc sulphate was not statistically significant. Moreover, failure of positive contribution of number and weight of pod per plant along with their dimension might be the reason for negative response of average pod weight per plant with applied treatments. However, this was found to be contradictory to findings of Rasheed et al., (2017) [14] .

Pod weight per plot had been analyzed and presented in the Table 6. Statistical analysis of data indicated that the different levels of humic acid failed to impart any significant influence on pod weight per plot. The recorded data showed that the highest pod weight per plot (4.9 kg) was observed in HA 0 (control) and lowest pod weight per plot (4.4 kg) was obtained under HA 1 . Moreover, non-significant influence of various levels of zinc sulphate on pod weight per plot was also noted with mere numerical variation in the data. However, maximum pod weight per plot (5.3 kg) was observed in Zn 0 (control), and minimum pod weight per plot (4.0 kg) was noted in Zn 1 . Further analysis of data indicated that variation of pod weight per plot with combined application of humic acid and zinc sulphate had no statistical significance. However, the maximum pod weight per plot (5.7 kg) was obtained in HA 2 Zn 0 , and the minimum value in this regard (3.8 kg) was recorded in HA 2 Zn 1 .

Pod yield per hectare (ton) Data pertaining to total pod yield per hectare was statically analyzed and represented in Table 11and Fig 9.

The recorded data indicated failure of remarkable variation in total pod yield per hectare with application of various levels of humic acid. Mere numerical variation, however, was recorded with the highest pod yield per hectare (9.9 ton) in HA 0 (control), and lowest value (8.7 ton) was observed in HA 1 .

The analyzed data presented in table clearly depicted that the various level of zinc application had failed to influence the pod yield per hectare markedly. However, the maximum pod yield per hectare (10.7 ton) was observed in Zn 0 (control), and minimum pod yield per hectare (7.9 ton) was recorded in Zn 1 . It was found that the combined application of various level of humic acid and zinc sulphate could not impart any significant variation in pod yield per hectare. However, the highest pod yield per hectare (11.4 ton) was recorded under combined application of HA 2 Zn 0 while the lowest pod yield per hectare (7.5 ton) was recorded in HA 2 Zn 1 . Failure to respond positively towards application of different humic acid and zinc as revealed in various yield contributing characters might have negative impact on the total yield per hectare. The result of this experiment with respect to yield per hectare was in contradictory with the finding of Rasheed et al., (2017) [14] .

Table 6: Effect of Humic acid and Zinc sulphate and their combination on average pod weight (g), average pod yield plant-1 (g), pod yield plot -1 (kg) and pod yield ha-1 (ton)

References

1. Abdel-Mawgoud AMR, El-Greudy NHM, Helmy YI, Singer SM. Responses of tomato plants to different rates of humic-based fertilizer and NPK fertilization. J Appl. Sci. Res. 2007;3(2):169-174.
2. Andreini C, Banci L, Rosato A. Zinc through the three domains of life. J Proteome Res. 2006;5:3173-3178.
3. Broadley MR, White PJ, Hammond JP, Zelko I, Lux A. Zinc in plants. New Phytol. 2007;173:677-702.
4. Buruchara R. Background information on Common Beans (Phaseolus vulgaris L) in Biotechnology, Breeding & Seed Systems for African Crops. Nairobi, Kenya: The Rockefeller Foundation; 2007.
5. Doddamani M, Tambat B, Gowda KM, Chaithra GN, Channakeshava S, Reddy BYN. Effect of foliar application of zinc and boron on vegetative growth, fruiting efficiency and yield in field bean. J Pharmacogn. Phytochem. 2020;9(5):1547-1551.
6. Hafeez BMK, Khanif YM, Saleem M. Role of zinc in plant nutrition: A review. Am J Exp. Agric. 2013;3(2):374.
7. Karakurt Y, Unlu H, Unlu H, Padem H. The influence of foliar and soil fertilization of humic acid on yield and quality of pepper. Acta Agric. Scand. B Soil Plant Sci. 2009;59(3):233-237.
8. Marschner H. Mineral Nutrition of Higher Plants. London: Academic Press Limited Harcourt Brace and Company; 2012. p. 347-64. ISBN:978-0-12-384905-384912.
9. Mauromicale G, Longo AMG, Monaco AL. The effect of organic supplementation of solarized soil on the quality of tomato fruit. Scientia Horticulturae. 2011;129(2):189-196.
10. Rasheed SM, Abdullah HM, Ali ST. Response of two hybrids of tomato (Lycopersicon esculentum Mill) to four concentrations of humic acid fertilizers in plastic house conditions. J Tikrit Univ. Agric. Sci., 2017, 17(1).
11. Yılmaz E, Naif G, Sezer S, Aysegul D, Necdettin S, Mine A. Interactive effects of humic acid and zinc on yield and quality in broccoli. Soil Water J. 2013;1(2):287-293.