CORRELATION ANALYSIS BETWEEN THE CONTENT OF PHOTOSYNTHETIC PIGMENTS, YIELD AND ANTIOXIDANT ENZYME ACTIVITY IN WHEAT VARIETIES

ABSTRACT

The presented information highlights the correlation between the content of photosynthetic pigments, yield, and the activity of antioxidant system enzymes in seedlings of various wheat varieties under the influence of nanoparticles of trivalent iron oxides, titanium dioxide, zinc oxide and aluminum oxide. The studies revealed a positive correlation between pigment content and wheat seedlings’ yield. Additionally, a linear dependence was identified between the activity of polyphenol oxidase (PPO) and the content of photosynthetic pigments, whereas superoxide dismutase (SOD) and catalase (CAT) showed a negative correlation with chlorophylls A, B and carotenoids. This may indicate a protective response of seedlings to changes in pigment content.

Keywords: correlation; chlorophyll A; chlorophyll B; carotenoids; antioxidant enzymes; yield

Under global climate changes, one of the key challenges in agriculture is the problem of food shortages in cereal crops. Therefore, increasing the yield of various hard and soft wheat varieties is one of the primary goals of the modern agronomic scientific community.

As is well known, the ability of plants to withstand environmental stress conditions is achieved through active defense mechanisms of the antioxidant system. Enzymes of this system (such as APO, CAT, SOD, etc.) play a particularly important role, directly influencing physiological processes like photosynthesis, which serves as the main energy source for growth processes [4, p. 802].

To evaluate the impact of antioxidant enzyme activity on the yield of seedlings Triticum durum Desf. and Triticum aestivum L. varieties, was necessary to conduct a correlation analysis. This analysis aims to establish the relationship between the content of photosynthetic pigments, biochemical indicators of the antioxidant system, and yield components of the studied crops.

High correlation values were observed in seedlings of Triticum durum Desf, demonstrating the significant impact of these parameters on yield compared to Triticum aestivum L. varieties. The conducted correlation analysis emphasizes the necessity of an integrated approach to improve agronomic indicators and to achieve high yields in both soft and hard wheat varieties.

Thus, the results of our experiments align with the literature and confirm the well-known scientific correlations between yield indicators in the leaves of various wheat genotypes under normal irrigation conditions [3, p. 19].

To achieve maximum productivity of the studied crops, it is essential to maintain the key yield indicators at an optimal level.

The study of the correlation between the content of photosynthetic pigments and enzyme activity in wheat seedlings represents an important area in understanding the mechanisms of plant resistance to various stresses. This interdependence can reflect both their physiological state and adaptive potential [1, p. 347].

The data presented below reflect the correlation analysis between the content of photosynthetic pigments (chlorophyll A, chlorophyll B, and carotenoids) and the activity of antioxidant enzymes in seedlings of various Triticum durum Desf. and Triticum aestivum L. varieties. This information provides a deeper understanding of the physiological characteristics of the studied wheat varieties and helps to determine their potential resistance to stress factors, which is crucial for improving the yield of cereal crops and developing breeding programs.

Table 1.

Correlation between photosynthetic pigment content and enzyme activity in hard wheat varieties (Triticum Durum Desf.)

Note: ** - highly significant correlation, p < 0.01; * - significant correlation, p < 0.05 (Pearson correlation).

Table 2.

Correlation between photosynthetic pigment content and enzyme activity in hard wheat varieties  (Triticum aestivum L.)

Note: ** - highly significant correlation, p < 0.01; * - significant correlation, p < 0.05 (Pearson correlation).

According to the data presented in tab.1, a positive linear correlation was observed between PPO activity and the content of photosynthetic pigments in seedlings of Triticum durum Desf. varieties, while SOD and CAT showed negative correlations with chlorophylls A, B, and carotenoids. This may indicate a protective response of the seedlings to changes in pigment content. As for Triticum aestivum L. varieties, a strong positive relationship between photosynthetic pigments was still evident. However, antioxidant enzymes either showed a weak significant correlation or no correlation at all with the pigments, as shown in tab.2. This suggests differences in the mechanisms of their interaction.

The effect of nanoparticles on the correlation between the content of photosynthetic pigments and the yield of various wheat varieties depends on both the type of nanoparticles and their impact on metabolic processes. Proper selection of nanoparticles and their respective concentrations enhances the correlation relationships, thereby contributing to an increase in the yield of cereal crops [2, p. 1].

The calculations revealed that the content of photosynthetic pigments (carotenoids, chlorophyll B, and chlorophyll A) positively correlated with key yield indicators (spike and grain weight, spike length, and overall yield). In all studied wheat varieties, carotenoids demonstrated a strong positive linear correlation with yield and growth components, highlighting their significant role in protecting the photosynthetic apparatus and enhancing the productivity of cereal crops.

In seedlings of Triticum durum Desf. varieties, the levels of chlorophyll A and carotenoids had a strong impact on yield components such as grain weight, spike length, and spike weight. The negative correlation between the chlorophyll ratio (A/B) and yield, as well as grain weight, suggests that the chlorophyll A/B ratio has a less pronounced effect on yield. This is likely due to changes in the structure of photosystems and their adaptation to light conditions (tab. 3).

Table 3.

Correlation between photosynthetic pigment content and yield indicators in hard wheat varieties (Triticum durum Desf.)

Note: ** - highly significant correlation, p < 0.01; * - significant correlation, p < 0.05 (Pearson correlation).

Table 3.

Correlation between photosynthetic pigment content and yield indicators in hard wheat varieties (Triticum aestivum L.)

Note: ** - highly significant correlation, p < 0.01; * - significant correlation, p < 0.05

(Pearson correlation).

According to the data presented in tab. 3, chlorophyll B had a greater impact on yield indicators compared to chlorophyll A in Triticum aestivum L. seedlings. The chlorophyll ratio (A/B) had a positive effect, particularly on yield, indicating a different metabolic dynamic of photosynthetic pigments in soft wheat varieties.

The material presented above emphasizes the importance of maintaining high levels of photosynthetic pigments to achieve maximum yield in the studied varieties of Triticum durum Desf. and Triticum aestivum L. This supports the literature findings on the synergistic interaction between the photosynthetic and antioxidant systems in plant organisms. In conclusion, the results of the correlation analysis align with the literature, which confirms the presence of positive relationships between yield indicators and photosynthetic pigment content, even in the absence of nanoparticle exposure [5, p. 295]. The presented results of the correlation analysis between the activity of antioxidant system enzymes, photosynthetic pigment content, and yield components in various varieties of Triticum durum Desf. and Triticum aestivum L. provide a deeper understanding of the relationship between the biochemical status of plants and their productivity. These findings can serve as a foundation for developing more effective agricultural technologies and methods to enhance the resilience of crops to stress factors.

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