USE OF REMOTE SENSING IN THE CONTROL OF CEREAL RUST
Falk R. Rittig and Hermann Bleiholder
BASF Aktiengesellschaft, Agricultural Research Station
6703 Limburgerhof/Pfalz, Federal Republic of Germany
Introduction and Objectives
Wheat is a crop of great significance to human nutrition. Crop area worldwide
in 1977 was around 233.8 million hectares; the yield was about 388.1 million
tons. The figures for Europe, excluding the USSR with its large fluctuations,
were 25.3 million hectares of crop area and - due to higher yields/ha -
83.9 million tons of wheat (1).
Wheat worth 2.71 billion US dollars was lost in Europe in 1977 due to weeds,
pests and plant diseases. The loss caused by plant diseases alone was 387.5
million US dollars (2, 3).
With this in mind a study was conducted with the following objectives:
Does remote sensing permit a qualitative and
quantitative statement to be made on plant
diseases in wheat and the success of modern
plant protection methods in controlling these
diseases?
Yellow rust (Puccinia striiformis)
In this study we limited ourselves to yellow rust, which occurs on wheat,
barley and rye and on numerous wild grasses. It presents a considerable
threat to wheat yields especially in the middle part of Europe, since in
comparison to other cereal rust fungi yellow rust is best adapted to low
temperatures. This enables it to multiply on winter cereals until late into
autumn and to spread early in the spring and begin fructification. On the
young plants the yellow uredospore-containing pustules appear singly at first
and then in parallel lines. Often they also occur on the ears. The teleuto-
spores, which remain hidden under the epidermis, are produced chiefly on the
stem and leaf sheaths in thin brown-black stripes (4).
Yellow rust reduces the assimilation area and, even as the infection begins,
worsens the plant's photosynthesis ability and respiration. In addition, the
transport of assimilates to the kernels is very quickly cut off. It is especial-
ly serious if the infection reaches the flag leaf and ears. In regions where
the infection occurs regularly, yield losses of up to 60 % have been recorded
(5).
Experimental data
The studies were made on an aerial photograph that had been taken in England
years ago by our subsidiary, BASF UK (6). A ZEISS-ICAREX camera with a 35 mm
lens and false-color infrared film was used. The aircraft was a Cessna. The
photograph was taken at an altitude of about 150 feet, at 5 o'clock on a June
afternoon in 1972.