Agriculture Reference
In-Depth Information
Fig. 3.4
Grafted watermelon
plant
Fig. 3.5
Placing pepper
transplants through plastic
mulch
improved with transplants, without additional thinning costs as required for direct
seeding. Furthermore, substantially less irrigation input is required to establish the
transplanted crop under a plasticulture system as compared to direct-seeding, which
is critical when growing vegetables in water restricted areas of semi-arid regions
(Fig.
3.5
).
Improved techniques aimed at modifying transplant root and shoot morphology,
and physiology, have been developed in the nursery to suppress plant height, enhance
plant compactness and condition or 'harden' transplants to better withstand post-
transplanting stress. Many of these techniques have beneficial post-transplanting re-
sponses on early vegetative growth (e.g. tomato, pepper), but few provide long-term
effects influencing reproductive development and yield potential. Numerous vari-
ables affecting growth and development of vegetable transplants in the nursery have
been researched and several have been implemented in commercial nurseries. These
include nitrogen, phosphorous and potassium management (Edelstein and Nerson
2001
; Dufault
1998
; Soundy et al.
2001
), supplemental light (Boivin et al.
1987
;
Fierro et al.
1994
), irrigation management and systems (Leskovar and Heineman
1994
), selection of cell volume in the tray (Bar-Tal et al.
1990
) and physiological
conditioning with abscisic acid (Goreta et al.
2007
; Agehara and Leskovar
2012
).
