er prevails. Preventive measures only
can be employed. These should consist in collecting and destroying
diseased fruit and in staking and trimming the vines to admit light and
air to dry out the foliage. Bordeaux mixture applied after the
development of the disease would be of doubtful efficiency and would be
objectionable on account of the sediment left on the ripe fruit.
DISEASES OF THE ROOT OR STEM
=Damping off.=--Young plants in seed-beds often perish suddenly from a
rot of the stem at the surface of the ground. This occurs as a rule in
dull, cloudy weather among plants kept at too high a temperature,
crowded too closely in the beds or not sufficiently ventilated. Several
kinds of fungi are capable of causing damping off, under such
conditions.
_Preventive measures_ are of the first importance. Since old soil is
often full of fungous spores left by previous crops, it is the wisest
plan to use sterilized soil for the seed-bed. When the young plants are
growing, constant watchfulness is required to avoid conditions that will
weaken the seedlings and favor the damping off fungi.
_Watering and ventilation_ are the two points that require especial
skill. Watering should be done at midday, to allow the beds to drain
before night, and only enough water for the thorough moistening of the
soil should be applied. Ventilation should be given every warm day as
the temperature and sunshine will permit, but the plants must be
protected from rain and cold winds. Work the surface of the soil to
permit aeration and do not crowd the plants too closely in the beds. If
damping off develops something can be done to check it by scattering a
layer of dry, warm sand over the surface, and by spraying the bed
thoroughly with weak Bordeaux or by applying dry sulphur and air-slaked
lime.
=Bacterial wilt= (_Bacterium solanacearum_ Erw. Sm.).--This disease,
which also attacks potatoes and eggplants and some related weeds, is one
of the most serious enemies of the tomato. It is known to occur from
Connecticut southward to Florida and westward to Colorado, but is most
prevalent in the Gulf States, where it has greatly discouraged many
growers.
_Its most prominent symptoms_ are the wilting of the foliage and a
browning of the wood inside the recently wilted stems. An affected plant
wilts first at the top, or a single branch wilts, but later the entire
plant yellows, wilts and dies. Young plants wilt more suddenly and dry
up. The di
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