MENDES, A. A.; http://lattes.cnpq.br/2575006725705971 Endereço; MENDES, Anderson de Araújo.
Resumo:
Due to the socioeconomic importance of the guava tree for the Northeast region of Brazil,
together with the high concentration of salts present in the region's waters and their deleterious
effects on most crops, it is necessary to use technologies that mitigate these effects of saline
stress on the plants, such as the application of elicitors, such as hydrogen peroxide, but there
are few studies that evaluate the best form of application. Therefore, the objective of this
research was to evaluate ways of applying hydrogen peroxide to guava seedlings irrigated with
saline water. The experimental design used was randomized blocks, in a 5 × 4 factorial scheme,
with five levels of electrical conductivity of irrigation water - CEw (0.3; 1.1; 1.9; 2.7 and 3.5
dS m -1) and four methods of application of hydrogen peroxide (M1 - without application of
H2O2, M2 - application via seed soaking, M3 - application via foliar spray and M4 - application
via seed soaking + foliar spray), at a concentration of 20 μM of H2O2, with three replications
and two plants per plot, totaling 120 experimental units. The effects of the treatments were
evaluated 120 days after transplanting, using growth and physiological parameters and
phytomass accumulation. Salinity reduced the growth, dry mass accumulation and relative
water content of guava cv. paluma. Foliar application of H2O2 attenuated the deleterious effect
of water salinity on guava seedlings in the leaf area, total dry matter and aerial part up to
conductivity of 2.7 dS m-1. The application of seed + foliar imbibition increases the number of
leaves, dry mass of leaves and dry phytomass of the aerial part in guava cv seedlings. paluma
irrigated with water of 3.5 dS m-1.
