Explore effective strategies and important facts about wheat stem borer management, essential for healthy crop yields. Tackle real-world agricultural scenarios with this balanced, informative quiz.
What is a common physical sign of wheat stem borer infestation observed in the field?
Explanation: Whiteheads with empty grains indicate that the developing grains are eaten by stem borers, causing the heads to appear white and empty. Yellowing leaf margin is more typical of nutrient deficiencies. Black rust spores are symptoms of fungal disease, not insect damage. Leafhopper burn is caused by sap-sucking insects, not stem borers.
During which stage of the wheat plant are stem borer larvae most damaging?
Explanation: The stem borer larvae bore into stems and cause the most damage during the heading stage, resulting in whiteheads. While tillering is important for plant establishment, infestation at this stage is less severe. Germination and maturity are not the primary damage periods for this pest.
Which cultural practice is effective in minimizing wheat stem borer populations?
Explanation: Timely removal and destruction of stubbles reduce overwintering larvae and break the pest's lifecycle. Flood irrigation can help pests survive by raising humidity. Overlapping sowing increases host availability, and excessive nitrogen may actually attract more pests.
Which biological control agent is commonly released to control wheat stem borer populations?
Explanation: Trichogramma wasps parasitize stem borer eggs, effectively reducing pest numbers. Ladybird beetles target aphids, earthworms improve soil health but do not attack pests, and predatory mites are more relevant for spider mite control, not stem borers.
Why is careful timing necessary when applying insecticides for stem borer management in wheat?
Explanation: Stem borer larvae hide inside stem tissues, making them less vulnerable to surface sprays; insecticides are most effective before extensive boring occurs. Roots do not absorb all chemicals targeted at insects. Spraying at harvest is ineffective since the crop is almost mature. Rain actually reduces, not boosts, effectiveness by washing chemicals away.