Liquid fertilization and conventional fertilization on soil fertility and agronomic and morphophysiological characteristics of Brachiaria brizantha cv. Braúna grass

J.F. Muricy, F.F. Silva, G.C. Dutra, T.M. Neto, I.C. Dutra*, C.J. Santos, R.R. Silva, R.S. Hermógenes, F.F. Cerqueira, A.J.V. Pires, N.V. Silva and B.E.F. Santos

State University of Southwest of Bahia, BR45700-000, Itapetinga, Bahia, Brazil
*Correspondence: ingriidyduutra@gmail.com

Abstract:

The objective of this study was to evaluate the effect of liquid and conventional fertilization on soil fertility, assessed by regrowth, and on the morphophysiological characteristics of Brachiaria brizantha cv. Braúna. The experiment was conducted in a greenhouse at the State University of Southwest Bahia, in Itapetinga-BA, from December 2018 to April 2019. The experimental design adopted was completely randomized, with four replicates, totaling 24 experimental units, in a 2×3 factorial scheme, comprising two types of fertilization (liquid and conventional) and three regrowths, with cutting intervals of 21 days. The results revealed that conventional fertilization promoted an increase in the levels of calcium (Ca) and phosphorus (P) in the soil, which, in turn, positively impacted the sum of bases and base saturation, reaching values of 5.6 cmolc dm^-3 and 54%, respectively, in the first regrowth. The dry mass production of the aerial part was influenced by both regrowth and the type of fertilization. A 27% reduction in dry mass production was observed from the first to the second regrowth, and a 16% reduction from the second to the third. On the other hand, conventional fertilization provided a 20% increase in dry mass production. The morphological variables of the plant were influenced by regrowth, with the exception of the leaf appearance rate (LAR), which did not present significant variations. A reduction in the other morphological variables was observed with each regrowth. Fertilization, in turn, influenced only the length of the flagellum leaf (LFL) and the total length of the tiller (TTL). The interaction between regrowth and fertilization was significant for leaf area, specific leaf area, leaf area index and leaf area ratio. The SPAD index, chlorophyll b and total chlorophyll contents were influenced by regrowth, with a progressive increase with each regrowth. Conventional fertilization promoted an increase in the SPAD index, with a value of 35.53, compared to 33.51 for liquid fertilization. The interaction between regrowth and fertilization was significant for the chlorophyll a:b ratio and carotenoids. The chlorophyll a:b ratio decreased with each regrowth. Conventional fertilization resulted in a 1.04% increase in crude protein content compared to liquid fertilization. Dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF) and ash contents were influenced by regrowth, with a progressive increase with each regrowth, except for ash, which showed a reduction. Regrowth demonstrated greater influence on the productive and morphophysiological characteristics of braúna grass. Conventional fertilization is recommended to promote improvements in soil fertility and increase the crude protein content of signal grass Brachiaria brizantha cv. Braúna.

Key words:

liquid fertilizer, nutritional composition, plant morphology, regrowth

Morpho-physiological effects of Stymjod foliar application on Dactylis glomerata L.

J. Sosnowski¹*, K. Jankowski¹, M. Truba¹, J. Novák², E. Zdun¹ and J. Skrzyczyńska¹

¹Siedlce University of Natural Sciences and Humanities, Prusa street 14, PL-08110 Siedlce, Poland
²Slovak University of Agriculture in Nitra, Tr. A. Hlinku street 2, SK94976 Nitra, Slovakia
*Correspondence: jacek.sosnowski@uph.edu.pl

Abstract:

The aim of the experiment was to study the effects of foliar application of a growth regulator containing iodine nanoparticles, with the trade name of Stymjod, on morphometrics, photosynthetic activity and chlorophyll content of Dactylis glomerate L. The following parameters were determined: the weight of fresh and dry matter of plants, leaves and roots, the number of shoots and leaves, potential (FV/Fm) and effective (ΔF/F_m’) quantum efficiency of photosystem, photochemical (qP) and non-photochemical (qN) quenching, as well as chlorophyll a and chlorophyll b content in leaf blades. The pot experiment was carried out in a breeding room. Stymjod was applied at 1.5%, 3% and 4.5% concentrations in the spray solution. It is a nanotechnology-based growth regulator, with easily assimilable forms of mineral and organic ingredients, favorably affecting plant ontogenesis. Plants were treated twice with a single dose of 50 mL of spray per pot. They were sprayed till they were completely covered with the liquid. Distilled water was used to spray control plants. The results were statistically processed using analysis of variance, while the significance of the differences between means was determined with Tukey’s test with P = 0.05. In the experiment it was found that different concentrations of Stymjod in the spray resulted in different response of plants. The best morphological effects were obtained using the concentration of the product exceeding 3%. In the test conditions Stymjod applied to D. glomerata increased the efficiency of the photosynthetic apparatus and the content of chlorophyll pigments.

Key words: