APHID attack this season is fast becoming a cause of worry for wheat growers. The attack of this sucking pest is visible almost throughout the state. Experts warn that if things get worse, a fall in the yield of wheat cannot be ruled out. Scientists of Punjab Agricultural University, who surveyed the wheat crop in districts of Ludhiana, Moga, Muktsar, Bathinda, Barnala, Jalandhar, Gurdaspur, Amritsar and Hoshairpur, have found moderate to high incidence of aphid in all the places. Jagdeep Singh, a farmer from Mehal Kalan village, claims, "The aphid attack is so severe this season that I am sure of a fall in yield. Moreover, our input costs have gone up as we have to spray the wheat fields due to this attack. While the timely sown wheat needs one spray, the late sown wheat needs almost two sprays.' B.S. Sidhu, Director Agriculture, is also keeping his fingers crossed as he says, "We cannot quantify the loss of yield percentage due to aphid attack as it is too soon to do so. But the attack is severe in places. The next 10 days are very crucial for the wheat crop. In case the temperatures keep rising the way they are, the pest will die a natural death, but if temperatures fall, we have a problem on our hands.' Dr N.S. Butter, head, department of entomology, PAU, explains, "Aphids are soft-bodied, green to blackish green louse-like insects found in small colonies on leaves and earhead. They suck the sap from the leaves and maturing grains. The high population of aphids at the ear head stage can cause substantial decrease in yield.' Scientists have warned the farmers to spray their crop only when five aphids per earhead are recorded from 10 randomly selected earheads in each of the four quarters of one acre. The aphid attack has also been noticed on fruit crops like pear, peach and citrus. In fruit crop, aphids suck the cell sap from leaves, flowers and growing tender shoots, resulting in shriveling and drying up of the plants. Punjab has about 34.8 lakh hectares under wheat. The total production of wheat in Punjab last year was around 146 lakh metric tonnes.