Seed number per plant
In the first and second years, growing conditions and nitrogen applications had a significant impact on seed number per plant. Zeolite applications were significant in the first year but insignificant in the second year (Table 4, 5). In both years, the seed number per plant was higher in irrigated conditions than in dry conditions.
Samarah et al., (2009) and
Kayan (2012) reported that the number of seeds per plant in chickpeas rose when irrigation was applied. The number of seed per plant in the first year was found to be 16.71 in zeolite+ and 15.87 in zeolite-. Zeolite improves soil fertility and absorbs a high quantity of water
(Susana et al., 2015). According to
Ghanbari and Ariafar (2013), the seed number per plant increased with zeolite application. Excessive precipitation in the second year of the experiment may have obscured the effect of zeolite (Fig 1). In terms of nitrogen applications, barnyard manure gave the best results in both years. The control plots yielded the lowest seed number per plant (Table 4, 5). Barnyard manure protects soil moisture because it contains more organic matter and enriches the soil in terms of nutrients.
Dogan (2019) investigated the effects of chemical and organic fertilizers on chickpea yield and yield components and obtained the lowest seed number per plant from control plots. Researchers reported that barnyard manure positively affected the seed number per plant.
In the first year of the experiment, irrigated + zeolite+ + barnyard manure plots yielded the highest seed number per plant, while irrigated + zeolite- + barnyard manure plots showed a lower pod number per plant (Fig 2). The experiment did not record excessive precipitation in the first year. Barnyard manure + zeolite+ plots may have given the best results because the zeolite absorbed water. The irrigated + zeolite- + barnyard manure plots yielded the highest seed number per plant in the second year of the experiment (Fig 2). Precipitation is very high in the second year of the experiment (Fig 1). The excessive precipitation prevented the observation of the zeolite’s effect in the second year.
Grain yield per plant
Growing conditions and nitrogen applications had a significant impact on grain yield per plant in both years, respectively. Zeolite applications were significant in the first year but insignificant in the second year (Table 4, 5). In both years, the grain yield per plant was higher in irrigated conditions than in dry conditions.
Agrawal et al., (2022) reported that with irrigation in chickpeas, grain yield per plant increased. The grain yield per plant was identified as 7.88 g in zeolite+ and 7.13 g in zeolite- during the first year. The zeolite application increased grain yield per plant. Zeolite improves soil fertility and absorbs a high quantity of water
(Susana et al., 2015). According to
Kazan (2007), zeolite application in chickpea increased grain yield per plant. Excessive precipitation in the second year of the experiment may have obscured the effect of zeolite (Fig 1). In terms of nitrogen applications, barnyard manure gave the best results in both years. The control plots yielded the lowest grain yield per plant (Table 4, 5). Barnyard manure helps to retain soil moisture due to its higher organic matter content and nutrient enrichment properties.
Ipeksen and Bicer (2021) reported that barnyard manure positively affects grain yield per plant in chickpeas.
In the first year, the application of zeolite shown elevated efficacy in irrigated regions, while exhibiting diminished effectiveness in dry areas. Therefore, the interaction of growing conditions x zeolite applications may have been important. Zeolite+ + irrigated plots yielded the highest grain yield per plant (Fig 3). While high grain yield per plant were obtained in irrigated areas, low values were obtained in dry areas for all of the nitrogen applications in the first year. Therefore, the interaction of growing conditions x nitrogen applications may have been important. Barnyard manure + irrigated plots gave the best results (Fig 3). In the first year, the zeolite+ plots yielded high grain yields per plant, while the zeolite- all nitrogen applications yielded low values. Therefore, the interaction between zeolite applications and nitrogen applications may have played a significant role. Barnyard manure + zeolite+ plots yielded the best results (Fig 4). The irrigated + zeolite- + barnyard manure plots yielded the highest grain yield per plant, whereas the dry + zeolite- + Isabion manure plots showed a lower grain yield per plant in the second year of the experiment (Fig 4). In the second year of the experiment, the application of zeolite under dry growing conditions resulted in a higher grain yield per plant compared to the non-application of zeolite. The zeolite’s water absorption property may not have been effective in the second year of the experiment due to excessive precipitation (Fig 1). In dry growing conditions, Isabion responded better to zeolite. Grain yield per plant was higher in zeolite+ than zeolite- in dry conditions at Isabion plots.
Biological yield
Growing conditions, zeolite applications and nitrogen applications had a significant impact on biological yield in both years (Table 4, 5). In both years, biological yield was higher in irrigated conditions than in dry conditions. Biological yield is considerably affected by environmental conditions in chickpeas. Chickpea is a drought tolerant plant, but its response to irrigation is quite good
(Arif et al., 2021). In this study, irrigation resulted in a corresponding increase in biological yield: 80.5% in the first year and 27.1% in the second year. In the second year of research, the increase in biological yield may have been low due to high precipitation.
Muruiki et al. (2021) found that there was a 27.7% increase in biological yield with irrigation in chickpeas. While the biological yield was higher in the zeolite+ plots in the first year, it was higher in the zeolite- plots in the second year. Zeolite provides richer growing conditions for plants by preventing the leaching of water and nutrients. Zeolite increases the drought resistance of plants in semi-arid regions
(Mondal et al., 2021). Amiri et al. (2021) reported that they achieved 45% more biological yield with zeolite application compared to control plots in soybeans. The biological yield was higher in the zeolite- plots in the second year of the experiment. Excessive precipitation in the second year of the experiment may have obscured the effect of zeolite (Fig 1). Barnyard manure gave the best results both years, while control plots gave the worst results in terms of nitrogen applications. Barnyard manure, which contains excess organic matter and plant nutrients, has positive effects on biological yield.
Pendergast et al. (2019) achieved 47% and 35% more biological yield at barnyard manure plots compared to chickpea control plots.
Dogan (2019) reported that chicken and barnyard manure yielded the highest biological yield, while chickpea control plots yielded the lowest biological yield.
While the highest biological yield was obtained from irrigated x barnyard manure plots, the lowest was obtained from the dry x control plots in 2019. While irrigated + traditional fertilizer and Isabion fertilizer increased biological yield by 72%, barnyard manure increased it by 92%. Therefore, the interaction of growing conditions x nitrogen applications may have been important (Fig 5). In 2020, the irrigated + zeolite- + barnyard manure plots yielded the highest biological yield, while the dry + zeolite- + Isabion plots yielded the lowest. While zeolite- + Isabion fertilizer plots gave the highest results in irrigated areas, zeolite- + Isabion fertilizer plots gave the lowest results in dry areas in the second year. Therefore, the interaction of growing conditions x zeolite applications x nitrogen applications may have been important (Fig 5).
Grain yield
Growing conditions and nitrogen applications had a significant impact on grain yield in both years. Zeolite applications were significant in the first year but insignificant in the second year (Table 4, 5). In both years, the grain yield was higher in irrigated conditions than in dry conditions. Environmental conditions significantly influence the grain yield in chickpeas. Chickpea is a drought tolerant plant, but its response to irrigation is quite good
(Arif et al., 2021). The experiment yielded 81% and 29% more grain in irrigated plots compared to dry plots in the first and second years, respectively.
Muruiki et al. (2021) found that chickpea grain yield increased by 60.3% with irrigation.
Gourav and Mishra (2019) reported that grain yield in pulses increased with irrigation. While grain yield was determined at 1730 kg ha
-1 in zeolite+, it was 1590 kg ha
-1 in zeolite- in the first year. Zeolite provides richer growing conditions for plants by preventing the leaching of water and nutrients. Zeolite increases the drought resistance of plants in semi-arid regions
(Mondal et al., 2021). Amiri et al., (2021) found that grain yield increased by 64% with zeolite application compared to control plots in soybeans. In the first year, the application of zeolite resulted in a rise in grain yield, however in the second year, no impact was observed. Both years were significantly affected by the growing conditions and nitrogen applications, resulting in a substantial impact on the grain yield per plant. In the second year of the experiment, sufficient precipitation and suitable climatic conditions prevented any determination of the zeolite’s effect (Fig 1).
Hoseini et al. (2020) reported that zeolite application did not affect grain yield in chickpeas. Barnyard manure gave the best results both years, while control plots gave the worst results in terms of nitrogen applications. Barnyard manure, which contains excess organic matter and plant nutrients, has positive effects on grain yield.
Janmohammadi et al., (2018) found that applying organic fertilizer to chickpeas increased grain yield.
Demir (2021) reported that the chicken manure plots yielded the highest grain, while the control plots yielded the lowest.
In the first year, all nitrogen applications yielded low values in dry areas, while irrigated areas yielded high grain yields. Therefore, the interaction of growing conditions x nitrogen applications may have been important. Barnyard manure + irrigated plots gave the best results (Fig 6). In the first year, the zeolite+ plots yielded high grain yields, while the zeolite- all nitrogen applications yielded low values. Therefore, the interaction between zeolite applications and nitrogen applications may have played a significant role. The best results were obtained from barnyard manure + zeolite+ plots (Fig 6). The irrigated + zeolite- + barnyard manure plots yielded the highest grain yield, whereas the dry + zeolite- + Isabion manure plots showed lower grain yields in the second year of the experiment (Fig 7). In the second year of the experiment, the application of zeolite under dry growing conditions resulted in a higher grain yield compared to traditional and barnyard manure plots. The zeolite’s water absorption property may not have been effective in the second year of the experiment due to excessive precipitation (Fig 1). In dry growing conditions, Isabion responded better to zeolite. Grain yield was higher in zeolite+ than zeolite- in dry conditions at Isabion plots.
Protein content
Growing conditions, zeolite applications and nitrogen applications had a significant impact on protein content in the first and second years (Table 4, 5). In both years, the protein content was higher in dry conditions than in irrigated conditions. Protein content generally increases due to decreased yield in arid conditions
(Dupont et al., 2006; Flagella et al., 2010). Bicer et al. (2004) found that the protein content of chickpeas decreased with irrigation. While the protein content is higher in the zeolite- plots in the first year, it is higher in the zeolite+ plots in the second year. Grain yield is higher in zeolite+ plots in the first year. For this reason, the protein content was lower in the zeolite+ plots. Yield and protein content are generally inversely proportional in arid conditions
(Dupont et al., 2006; Flagella et al., 2010). Precipitation was too high in the second year (Fig 1) and the zeolite may have prevented the leaching of plant nutrients, especially nitrogen.
Kharazmi and Tan (2020) found that zeolite application did not affect the crude protein, ADF and NDF rates in alfalfa.
Tutar (2019) was unable to detect any effect of zeolite application on corn’s crude protein ratio. In both years of research, protein content was higher in all nitrogen applications than control plots. The same statistical group included all nitrogen applications.
Yagmur and Engin (2005) reported that chickpea protein content increased with increasing nitrogen doses.
While barnyard manure plots in irrigated areas have a low protein content, barnyard manure plots in dry areas have a higher protein content in the first year of the experiment. While the protein content is lower in the zeolite- plots, it is higher in the zeolite+ plots. Therefore, the interaction between growing conditions, zeolite applications and nitrogen applications may have played a significant role (Fig 8). In the second year of experiments, the protein content in zeolite+ plots is higher than in zeolite- plots, both in dry and irrigated growing conditions. Therefore, the interaction of growing conditions and zeolite applications may have been important (Fig 8). Protein content increased in both growing conditions with zeolite application.