| When a standing crop of wheat or barley, planted in the hope of a normal
season, has been overtaken by unexpected frosty weather, there is little
that can be done as a protective measure. The few that are available depend
for their effectiveness in the ability of the farmer to recognise frost
injury immediately after the occurance of frost. This is difficult since
the symptoms can often be mistaken for those of fungal diseases. The following
are a few of the hints to recognise frost injury. If one runs a hand back
and forth brushing the plants damaged stalks usually bend at the point of
injury. Stripping off the leaf sheath will expose injured nodes and internodes.
Developing ears appear water soaked and flabby. Emerged ears, when affected
have glumes gaping, or appear white and bleached. Frost injury can affect
the central or basal spikelets in the ear and can thus be distinguished
from the injury by hot, dry winds that affect the terminal spikelets. Once
the frost injury has been recognised, and the extent damage assessed, the
steps to be taken in the treatment of the frosted crop, depend on the economic
evaluation of the alternative choices, which are as below: i. irrigate, preferably by sprinkler irrigation: ii. cut for hay, or silage, or even graze off: iii. leave the crop untreated in the hope of some recovery. References ANONYMOUS 1959. Frost injury to wheat. The Agricultural Gazette, June, 312-316. GROSS, F.C. 1971. Frost damage in cereals. Paper NO. 6, Branch Conference, Western Australia, pp 5. LANDERS, J.N. & K. WITTE 1967. Irrigation for frost protection. In Irrigation of Agricultural Lands. Ed. R.M. HAGAN, H.R. HAISE and T.W. EDMINSTER. No. 11 Agronomy. ASA Madison, Wisconsin, 1027-1064. MARTINIC, Z. 1974. Vernalization and photoperiodism of common wheat in relation to life cycle and cold tolerance. Proc. 1st FAO/SIDA seminar on improvement and production of field food crops for plant scientists for Africa and the Near East, 351-361. SINGLE, W.V. 1968. Variation in resistance to spring frosting in T. aestivum and related species. Proc. 3rd Wheat Genetics Symposium, Canberra, 282-287. |
| <-- Back |