In screening of 10 local and exotic genotypes for aphid infestation in
the field: Sakha 8 and Copper showed high susceptibility, Line 4230/91. IDO.
377 and Sakha 69 were susceptible (susceptibility ranged from 80 to 9 1%).
Little susceptibility (60-61 %) was detected on Hatri ENo. 4 and Enklab, while
Pick, Hatri ENo. 16 and Seren were resistant (23 - 4 1%). At the end of March
and beginning of April, susceptibility to aphid infestation increased for all the
examined genotypes except two only: Seren and Hatri ENo. 16 (ranged from 62
to 73 %). On April, 20th in some genotypes as Seren showed resistance (42%).
While, at the end of month population of aphids decreased sharply on all of the
examined genotypes mainly due to the dryness of plants and migration of aphids
to other host plants.
On plants, the greatest number of apterous adults was found on Sakha 8
Sakha 69, IDO. 377, Seren, 4230/91, Hatri ENo. 4 and Enklab, While, the
genotype Hatri ENo. 16 showed moderate number of the apterous adults. The
lowest number of adults was found on the plants of pick genotype which showed
the ability for resistance to the apterous adults.
All the genotypes showed higher numbers of alate adults except
Pickand Hatri ENo. 16.
The highest numbers of nymphs were counted on Sakha 8. IDO. 377,
Sakha 69, Line 4230/91. Hatri ENo. 4 and Enklab. Moderate numbers of
nymphs were detected on plants of Seren Copper and Hatri ENo. 16, while the
lowest numbers occurred on plants of Pick genotype showing resistance to the
infestation with apterous and alate forms and also the aphid nymphs.
Heading date. 1000-kernel weight. spike length number of spikelets per
spike and grain yield per plant were recorded.