dead central leaves. Controlled with seed dressings.
which are alternate hosts.
Hessian Fly—less harmful on barley than on wheat.
Pentatomid Bugs—attack seed at the milky stage. Controlled with insecticides.
worst on poor, weak crops.
Rice Weevil—attacks stored seed. Controlled by heat treatment.
Diseases: also mainly the same ones that attack wheat. Stem Rust and Leaf Rust
(Puccinia spp.) are the most serious, causing loss of yields and thin seed. Also Net
Blotch, Spot Blotch, Barley Stripe, Powdery Mildew, Barley Leaf Blotch
(Rhyncosporium secalis), Smuts (especially Loose Smut Ustilago), Scald and virus
diseases such as BYDV , BaYMV and BSMV (Barley Stripe Mosaic Virus).
varieties. BaYMV also affects
YIELD
FAO’s estimate of the global average for barley in 2004 was 2.68 MT/ha, varying
from 0.5–1 MT/ha in low input systems to 3–8 MT/ha in higher input systems. The
Netherlands reported the highest average yield in 2004 at 7.87 MT/ha while the
lowest was Lesotho at 250 kg/ha.
The maximum attainable yield is well over 8 MT/ha. Some 6-row varieties can
attain 10 MT/ha under very intensive management.
UTILISATION
About half of the barley grown is used as animal food, the grain normally
being mixed with other foods to produce animal food concentrates. Due to its
low gluten content, barley is not suitable for making leavened bread, though
unleavened barley bread is quite tasty.
The growing crop can be used as fodder, and can also be grazed, especially
when irrigated. If grazing is stopped early enough a reasonable grain yield can
result—or the crop can be cut for hay or silage.
Barley is the most important grain used for brewing beer, for which special
malting varieties are needed. In order to be acceptable for malting the grain
sample should be of specific quality regarding its Nitrogen content, size,
germination, moisture and mealiness.
Malting quality seed is normally more valuable than food quality seed.
Aphids—especially on young plants, and after long periods of dry weather.
Barley Fly—not found on wheat. Larvae eat growing points of seedlings, producing
Paddy Bugs—attack seeds. Partially controlled by removing nearby wild grasses,
Chinch Bugs—
elsewhere. The vector is a soil—
with pyrethroid sprays, seed dressing (eg Imidacloprid based) or destroying any —
any green bridge.
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Pests: mainly the same insects that attack wheat:
(1) Barley Yellow Dwarf Virus. Main control is by controlling the aphid vector
(2) Barley Yellow Mosaic Virus. An increasingly serious problem in Europe and
borne nematode. There are some tolerant barley
GROWING FOOD – THE FOOD PRODUCTION HANDBOOK
(1) (2)some wheat varieties.