ABSTRACT
Two field experiments were conducted at Sakha agricultural farm,
Kafer El-Sheikh Governorate Egypt, during 2018/2019 and 2019/2020
seasons, to study the impact of nitrogen in three rates 60, 80 and 100 kg
N fed-1, potassium with the rate of 24, 36 and 48 kg K2O fed-1 as soil
application and, a mixture of three trace nutrients i.e. Zinc (1g/L),
Manganese (1g/L) and Fe (2g/L) as a foliar application on insect
infestation, yield and quality of sugar beet. The obtained results revealed
that the infestation by beet fly, tortoise beetles and beet moth increased
gradually and significantly by increasing nitrogen rate from 60 to 100 kg
N fed-1. Further, increasing potassium fertilization caused significant
reduction in insect infestation. Moreover, foliar application of the used
mixture of trace elements significantly reduced infestation beet by P.
mixta. At the same time, insignificant reduction on the other two pests
has been detected. However, individual root specification, root yield,
sugar yield, sucrose and purity were maximized corresponding to 80 kg
N fed-1. More nitrogen application decreased all the studied traits except
top yield and TSS. On the other hand, increasing potassium fertilizer
from 24 up to 48 kg K2O fed-1 positively enhanced root diameter, root
length, root weight, root, top, sugar yields/fed. and TSS. Nevertheless,
sucrose and purity were maximized as potassium fertilized added at the
rate of 36 Kg K2O fed-1. Moreover, foliar application of trace elements
significantly improved all beet productivity characteristics and quality
traits.
To conclude that fertilizing beet plants with 80 kg N fed-1, 36 kg
K2O fed-1 with sprayed the mixture of trace elements maximizing yield
and quality of sugar beet and had negative impact on pests under study.
Key words: Sugar beet, nitrogen, potassium, microelements, insect pests
infestation