R. Cakmakci et al., ROOT YIELD AND QUALITY OF SUGAR-BEET (BETA-VULGARIS L.) IN RELATION TO PLANT-POPULATION, Journal of agronomy and crop science, 180(1), 1998, pp. 45-52
Introduction of genetic monogerm seed and the advancement of agricultu
ral techniques raised the possibility of eliminating costly thinning o
perations in sugar beet farming. However, this requires high and unifo
rm seedling emergence to provide prerequisite plant populations in the
held. This work investigated the minimum levels of seedling emergence
for non-thinned sugar beet farming. The experiment was carried out in
a loamy soil to investigate the effects of three levels of emergence
(60, 50 and 35%) and two intra-row spacings (8 and 15 cm) with or with
out thinning using seed source of graded viability of cv Eva in 1992 a
nd 1993 under field conditions in Eastern Anatolia. Plant population t
hroughout the growing period was monitored and data were taken of yiel
d and quality parameters. On average, 60, 50 and 35% emergence levels
were achieved using seed source of 90, 72 and 54% viability range, whi
ch resulted in different levels of plant stands depending on intra-row
spacing and thinning. Plant density at harvest ranged between 49 500
and 124 500 ha(-1) on average depending on initial establishment, intr
a-row spacing and thinning. Root yield and sugar yield were the highes
t at plant stands between 90 000 and 100 000 ha(-1), below or above of
which declined. Impurity contents (e.g. Na, K and a-amino N contents)
and extractable sugar content decreased but sugar content and clear j
uice purity enhanced as plant stands at harvest increased.