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Plastid DNA of the moss Physcomitrella patens has been sequenced. An open reading frame (ORF 315) was identified downstream from rbcL, between trnR-CCG and psaI. This ORF shares homology with zfpA, a putative regulatory gene in Pisum sativum. The moss ORF is preceded by a Shine-Dalgarno sequence, two plastid promoter consensus sequences, and three TATA boxes. A specific probe detected three transcripts of low abundance in the wild-type moss and a cytokinin-sensitive chloroplast mutant. Steady state levels of zfpA transcripts were different in the two genotypes. In mutant protonemata treated with cytokinin, steady state levels of the largest transcript decreased significantly.

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Blueberries are an increasingly important h~ticultural crop in New Zealand and other coun~es. Fruit ripen over an extended period, with considerable differences in storage and other qualities. Tissue concentrations of abscisic acid (ABA), 1-aminocyciopmpane-l-carboxylic acid (ACC), malonyl-ACC and also ACC oxidase activity and ethylene evolution were determined at 5 stages of colour development on 2 harvest dates. These were related to &y matter, sucrose and reducing sugar content. ACC concentrations, and the proportion conjugated varied between harvest dates, while ethylene evolution and ABA concentrations were similar. ABA concentrations were high relative to other fruit, exceeding 10 nmole/g fw prior to full ripeness. ABA was present in higher concentration in mesocarp than in seeds or pericarp/cuticle. It is proposed that ABA is implicated in dry matter acquisition, but is not a primary determinant of colour development or ethylene regulation.