Biology Reference
In-Depth Information
a $60 prize for the best method of preventing pre-
mature decay of peach trees. Present in eastern
states on peach, almond, nectarine, apricot and
plum. Not found west of the Mississippi or in the
South. In peach, clearing of veins, production of
thin erect shoots with small chlorotic leaves, pre-
mature ripening of fruit (with reddish streaks in
flesh and insipid taste) is followed by death of the
tree in a year or so. The little peach strain of the
MLO causes distortion of young leaves at tips of
branches, small fruit, delayed ripening. Plum is
systemically infected, with few obvious symptoms.
Transmission is by the plum leafhopper or budding.
Control
Budsticks and dormant nursery trees
can be safely treated with heat sufficient to kill
the MLO (122
F for 5 to 10 min), but cured trees
are susceptible to reinfection. Most effective con-
trol is removal of wild plum trees around peach
orchard and spraying to control leafhoppers.
Potato Apical Leaf Roll and Arizona Purple
Top Wilt Caused by aster yellows.
Strawberry Green Petal Perhaps due to a strain
of aster yellows MLO, as is chlorotic phyllody
reported from Louisiana. Flowers have enlarged
sepals, small green petals.
Bud Proliferation and Delayed Maturity,on
soybean.
Decline of ash.
Lethal Yellowing on palms.
Phloem Necrosis of chrysanthemum.
Spiroplasma citri
Corn Stunt
. Has been
reported on corn, onions, horseradish, shepherd's
purse, yellow rocket, and wild mustard.
Stunt of blueberry.
Virescence on horseradish.
Witches' Broom on pigeon pea (
Cajanus
cajan
), and black raspberry.
Witches' Broom on Japanese persimmon,
and lilac.
Witches' Broom and Yellowing on annual
statice.
Yellows of elm.
