The Delta independent., 1920-04-30

specified later. 1t is recommended
that certified seed be marketed in
new sacks containes.
Oversize tubers being wastefM and
less desirable than properly grown
uniform, medium sized potatoes, the
"seed size" standard shall be from
two to twelve ounces, with a varia.
tion tolerance of five per centum for
sizes larger than IL ounces.
Since mixed, varieties Of seed pota-
toes are q potent cause of economic
loss in potato production and market.
ing,a rigid adherence to trueness of
name and type is necessary. Furth-
ermore, since the practice of renam-
ing old varieties or changing the
names of named varities, through
ignorance, or with malicious inten-
ton to defraud, is detrimental to the
potato industry, the publication of
Prof. William Stuart, U. 8. Depart
ment of Agriculture, Washington,
D. c., in Group Classification and
Varietal Descriptions of Some Amer
lean Potatoes" has been adopted as
the standard for correct names,
groups and variety descriptions.
Since Offtype, or runout strains of
any given variety are essentially as
detrimental to successful potato pro-
duction as mixtures of varities, no
stock shall be certified or planted
with the expectation OF producing
potatoes for certification that are not
uniformly typical in all characteris-
tics for that particular variety in the
district where it is grown.
Any attempt to sell uncertified seed
as certified stock will be considered
sufficient reason for refusing to GER
tify all stock for that grower in the fu-
ture.
No potatoes shall be certified that
show by inspection on vine or tuber
the presence of the diseases known
as black wart (chrysophlyctis endo-
biotica schlib) powdery scab (spon-
gospora subterranea Wallr Johns)
and violet rhizoctonia trhizoctonia
crocorum-Pers. d. c. and the pests,
eelworm (heterodera radicicola-
Greet. Mul) and potato tuber moth
CPhthorimaea operculella Zeller)
W. PolutoSS nc CcI tllitu MulCu
show upon the tuber at final inspec-
ton more than five per cent scab
tactinomyces scabies Thax-Gussow)
with no deep scab postules permiss-
ible.
| Not to exceed five per cent of the
| tubers, as determined by transverse
| secontions of stem and of tuber in the
final tuber inspection shall be inter
preted as meaning wilt diseases as
| fusarium Oxysporum (Schlect) verti-
cillium alboatrum (Reinke and Berth)
bacillus phytophthorus Appel ct al)
Regulations Governing Vine Inspec-
| tion.-1nspection Of potatoes is not
only necessary after the crop is har-
| vested but also during the growing
season to determine trueness to type
and variety, and freedom from di-
sease, stand, and general vigor This
shall be accomplished by an inspec-
ton OF the potato plants in the field
at blooming time. again just prior to
maturity of the plant, at digging
time. and when the potatoes have
been graded and ready for shipment
The inspector should be notified
| when the seed field is in full bloom,
| and again two weeks before the tops
die.
Bloom Time Inspection.-Variety-
More than per cent. vasietal mix
ture at this inspection shall disqusli-
fy for certification.
Constitutional vigor.-A variation
in type Of plants in excess OF 10 per
cent, indicating weak, degenerate or
inferior plants shall dtsqualify for
certificatiOn. Over per cent. of
missing hills will disqualify
Disease.-More than 10 per cent. of
the plants at this inspection affected
by the following diseases. or more
than 5 per cent. affected by any Of
the following groups of diseases shall
disqualify the field for certification:
l. Well defined curly dwarf
leaf roll MOSAIC" or other inher-
tied weaknesses, combined.
2. wilt diseases and "blackleg"
combined.
3. Rhizoctonia (black scurf).
4. Early blight (Macrosporium So
lani, f & NJ occurring to the extent
that the plants are weakned will dis
qualify.
Immediately following the bloom
time inspection all diseased OF objec-
tiOnable plants must be rogued. No
rogueing shall be done except during
the week following some inspection.
| Second Plant Inspection.-At this
inspection the tolerances governing
| certification shall be: Not to exceed
5 per cent. Of mosaic dwarf, leaf-roll
and other inherited weakness COM
| hinad: not to excead mar cent of