Effect of Protein Gel Treatments on Biometric and Biochemical Attributes of Tomato Seedlings in Greenhouse Condition

Abstract

Protein hydrolysates are widely used in agricultural crops for improving plant nutrient uptake, growth, yield, and fruit quality. Tomato (Lycopersicon esculentum Mill.) is one of the most important vegetables consumed around the world both for its good taste and rich content in vitamins, minerals, lycopene, and β-carotene. The objective of the present study was to assess the effect of new stimulant products based on protein hydrolysates obtained from animal tissue by-products on tomato seedlings. Given the increased intake of amino acids, it is expected that this treatment will exert beneficial effects on the development of certain vigorous seedlings, representing the premise for obtaining superior tomato plants and the improvement of the production and quality of tomato fruit. Two variants of protein gels based on gelatin and keratin hydrolysates were obtained by processing bovine hide and wool and were used for periodical root applications on tomato seedlings cultivated in a greenhouse. During the experiment, the biometric characteristics of seedlings were measured weekly. The content of photosynthetic pigments, dry weight, sugars, and polyphenols were analyzed, and the antioxidant activity was assessed in the leaves. The research performed showed that applied biostimulant treatments increased the content of photosynthetic pigments by 10%, the content of sugars by 75%, and the content of polyphenols by 16% compared to the control untreated variant. Between the variants of protein gels tested, the best results were obtained by applying a mixture of bovine gelatin and keratin.

Innovative Protein Gel Treatments to Improve the Quality of Tomato Fruit

“…Previous research conducted by Balan et al [18] on tomato seedlings showed that application of protein gels increased the content of assimilatory pigments (chlorophylls and carotenoids), sugars, and phenolic compounds in the leaves when compared to untreated plants. This research assumed that development of some vigorous seedlings would result in a higher production of tomatoes with improved nutritional qualities, so the present study aimed to evaluate the biocompound accumulation in the tomato fruit under biostimulant treatment.…”

“…The physicochemical characteristics of the protein gels were performed as previously described [18] and are presented in Table 1. The data are very similar, and differences in the bloom test and viscosity are due to the addition of keratin to the gelatin-based gel.…”

Amino Acids Biostimulants and Protein Hydrolysates in Agricultural Sciences

“…Protein hydrolysates, especially those that contain antioxidant peptides, are obtained from natural components, and many researchers and scholars consider them biostimulants because of their minimum side effects, easy absorption, low cost, high activity, and lower molecular weight [ 123 , 124 , 125 , 126 , 127 , 128 , 129 , 130 ]. Protein hydrolysates and peptides can be used as notable ingredients in the formulation of functional foods [ 131 , 132 , 133 , 134 , 135 , 136 , 137 , 138 , 139 , 140 , 141 ]. They can be used as foliar sprays or through drip irrigation systems, and the amino acids can be absorbed through both leaves and roots [ 142 , 143 , 144 ].…”

Germination Study of Some Protein-Based Gels Obtained from By-Products from the Leather Industry on Tomato and Pepper Seeds

“…According to Golka et al [4], the use of biostimulators in the form of a gel helps to maintain the moisture of the plant by extensive water absorption, being mixed with the Gels 2024, 10, 75 2 of 16 soil, increasing the water capacity, counteracting water tensions by ensuring humidity for the plants, and reducing the evaporation of the water from the soil [5]. Another study [6] highlights the impact of the application of protein gels on tomato seedlings compared to samples of seedlings not treated with protein gels. After analyzing the leaves of tomato seedlings, it was found that the seedlings treated with the protein gels had a higher content of pigments, carotenoids, total phenolic compounds, and soluble sugars.…”