In order, to assess the effects of foliar spry time by different micronutrients
nanoparticles on sunflower (Helianthus annuus L.) cultivar, Sakha-53, a field experiment
was organized in a randomized complete block design using strip plot
arrangement with three replications during 2019 and 2020 seasons at Agronomy
Department Farm, Agriculture Faculty, Assiut University, Egypt. Three different
foliar spraying times of different micronutrients nanoparticles were allocated
horizontally while eight treatments of spraying with different Micronutrient
nanoparticles (2 gm/L) were arranged vertically. The results showed that foliar
spraying twice after 30 and 50 days from sowing was significantly increased
plant height, stem diameter and head diameter in both seasons. In addition, the
highest mean values of seed yield (t fed.-1) and oil yield (kg fed.-1) were recorded
when foliar spraying was done threes after 30,50 and 70 days from sowing.
Foliar application of Iron, Manganese, and Zinc nanoparticles was superior all
other treatments in this respect and registered the highest mean values of all studied
yield attributes, seed yield, and oil yield in both seasons. The interaction between
spraying time numbers and micronutrients nanoparticles significantly affected
all sunflower yield attributes in both growing seasons. The highest mean
values of seed yield (3.47 and 3.55 t fed-1) and oil yield (1765.88 and 1770.67 kg
fed-1) were obtained from the interaction between T3 × S7 (foliar spraying three
times after 30, 50 and 70 days from sowing date × spraying with Iron, Manganese
and Zinc). It was concluded that foliar spray threes time at 30, 50 and 70
days from sowing using Iron, Manganese and Zinc nanoparticles could be used
as a suitable method for improving seed yield and its attributes of sunflower cultivar,
Sakha-53.