Chemically-induced resistance against multiple pests in cotton

Plants can be treated With natural elicitors to induce resistance to herbiv ores. The effects of induced resistance to cotton aphids Aphis gossypii Glo ver (Homoptera: Aphididae), two-spotted spider mites Tetranychus urticae Ko ch (Acari: Tetranychidae), and western flower thrips Frankliniella occident alis (Pergande) (Thysanoptera: Thripidae) in cotton plants were investigate d using applications of the natural plant inducer, jasmonic acid (JA). Pref erence was reduced by more than 60% for aphids and spider mites, and more t han 90% for thrips on JA-induced leaves compared with control leaves. Survi val of aphid nymphs was reduced by two-fold and percentage of nymphs attain ing the adult stage was reduced by about eight-fold on induced leaves compa red with controls. Induction reduced survival and reproduction of adult aph ids by about 40% and 75%, respectively. Induction did not affect survival i n spider mites or thrips. However. induction reduced egg production in spid er mites by more than 75% and feeding in thrips by up to 80% compared with controls. Induction reduced leaf area in cotton seedlings by about 28%. The implications of our results for cotton pest management are discussed.