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Late-season
nitrogen applications in high-latitude strawberry nurseries
improve transplant production pattern in warm regions
Daniel S.
Kirschbaum1*, Kirk D. Larson2, Steve
A. Weinbaum2 and Theodore M. DeJong2
1Instituto
Nacional de Tecnología Agropecuaria (INTA).
EEA Famaillá, Argentina.
2Department
of Plant Sciences, University of California Davis, CA, USA.
*Corresponding author. E-mail:
dkirschb@correo.inta.gov.ar.
Tel:
+54-3863461048. Fax: +54-3863461546.
Accepted 17 September, 2009 |
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The influence of late-season nitrogen (N) applications
on the fruiting pattern of strawberry runner plants of
‘Camarosa’ was determined over three growing seasons.
Experiments were carried out in high-latitude nurseries in
northern California and fruit production trials were
established in southern California. A total of 80 kg/ha of
foliar nitrogen was delivered in three applications to the
nursery in late summer. Late-season foliar nitrogen
applications: (1) increased early yields (+22% on average)
as well as the number of early marketable fruit, (2) did not
affect total season yields, fruit size, appearance and
firmness and (3) resulted in greater N concentration in
leaves, crowns and roots. Runner plants with leaf N
concentration within the sufficiency range (1.9 - 2.8% of
dry mass) produced the highest early yields. Total
nonstructural carbohydrate concentrations decreased in most
of the N-treated plants. Apparently, nursery late-season
foliar nitrogen applications enhance N mobilization to crown
and root, stimulate plant activity during the period of
flower differentiation after planting, accelerating flower
development and contributing to the advancement of fruit
production.
Key words:
Fragaria x ananassa Duch,
foliar urea, carbohydrates, high-latitude nursery, plant
maturity. |
