Figure 1.

Stimulation of cell division on pods of an Np pea line (a derivative of C887-332; ref. 10) by several treatments. (a) Scanning electron micrograph showing the response of a pod from an Np pea line to oviposition by a pea weevil. The pod was obtained from a field-grown plant several days after oviposition. E, egg; N, neoplastic tissue formed in response to oviposition. (b) Cross section through a pod showing neoplastic tissue formed in response to pea weevil oviposition. Pod was harvested and fixed 8 days after oviposition. (c) Neoplasms present 1 week after application of various amounts of 2 (bruchin B; Fig. 4a), a compound present in extracts from the cowpea and pea weevil. Amounts applied as 1-μl drops in 50% (vol/vol) ethanol were (from left) 10, 5, 1, 0.5, and 0.0 pg. (Bars = 100 μm.)