Agriculture Reference
In-Depth Information
many pineapple-growing areas where plastic mulching is too costly, mulching
with straw, grass, sugar cane baggasse or other available materials is done.
Crop rotation for nematode control is a possible practice when economical.
Fumigation
'Smooth Cayenne' is susceptible to several plant parasitic nematodes, which
if left unchecked can devastate the plant. Pre-plant fumigation of the soil
with a volatile nematicide to control root-knot and reniform nematodes is an
established practice in Hawaii. In recent years, loss of some fumigants has
occurred due to health and environmental concerns. Non-volatile nematicides
are applied post-planting through drip irrigation systems, to provide nematode
control later in the plant crop and during ratoon crop development. Even
with signifi cant nematode feeding pressure, it is often possible to produce an
acceptable mother-plant crop. However, under such pressure ratoon crop
growth and yield will probably be severely reduced, possibly to the point of
complete ratoon crop failure, because ratoon yields are highly dependent upon
the health of the plant crop root system. In South Africa, where
Meloidogyne
and
Helicotylenchus
nematodes
are serious problems in pineapples, pre-plant
dipping in a systemic nematicide followed by post-plant spraying at monthly
intervals for 12 months increases a plant crop yield by 11 t/ha. In the absence
of any history of nematode problems, soils should be assayed for nematodes
before embarking on costly nematode control programmes.
Planting
Planting is commonly done manually with a 25 cm-long, trowel-shaped
planting tool. Good soil preparation makes it easy to place the propagule deep
enough into the soil to assure good plant-to-soil contact. Marked cords may
be stretched from one end of the fi eld to the other to keep rows aligned and to
indicate plant spacing. In Hawaii, spacing is established by factory marking on
polyethylene mulch. In Queensland, Australia, South Africa and Mexico, some
growers use a planting machine similar to a vegetable transplanter.
Crowns, slips and suckers are planted separately in dif erent fi elds.
Crowns are smaller than and somewhat more uniform in size than slips and
suckers. Slips and suckers can be large, with size mostly determined by the
length of time they remain on the plant. Sizing prior to planting is crucial
in order to obtain uniform-sized plants at the time of fl oral forcing, to assure
a uniform-ripening fruit crop (Py
et al.
, 1987). Large suckers have a high
tendency for precocious fruiting, being physiologically mature, especially
when sucker weight exceeds 600 g. The following weight classes are
