Fig. 3

Six basic EPG waveform maps of male cotton aphid feeding on cotton. Np (non-penetration) waveform appears due to stylet withdrawal; waveform C (the probing period waveform consists of aphid mouth needles probing between mesophyll cells or outside the sieve molecules in phloem); Pd (potential drops, the aphid's mouth needles probe inside the living cells); F (the aphid mouth needles encounter mechanical resistance outside the plant tissues and cells); E1 (the aphids' mouth needles secrete saliva into the sieve elements); 6) E2 (the aphid mouth needles feed passively within the screen tube)