Plans are presented for the construction of a three-channel reversible peristaltic pump that can operate at a rate of 45 ml/minute per channel. The cost of this peristaltic pump is about $84 compared to $620 for a commercially available peristaltic pump of similar design and capability. An electronic control scheme for pump operation is presented also.
Brent Tisserat and Paul Galletta
Brent Tisserat and Paul D. Galletta
Flowering and fruit production were obtained from cultured shoot tips of `California Wonder', `Super Cayenne', and `Zippy' peppers grown in a liquid Murashige and Skoog (MS) medium without growth regulators. Thirty-day-old pepper shoot tips, derived from seedlings germinated sterilely, were cultured in a 6-liter polycarbonate container coupled to an automated plant culture system (APCS). Plants were given ten daily, 30-minute, compressed-air applications at 300 ml/minute. These shoots began flowering after an additional 60 to 90 days in culture and flowered continuously thereafter. About 5% to 10% of the flowers set fruit. Maximum fruit size obtained was ≈25% to 75% of the size of fruit produced on plants grown in vivo. In contrast, no flowering occurred from shoot tips grown in 25 × 150-mm culture tubes containing agar medium and subcultured every 8 weeks to fresh medium. Immature fruit excised from plantlets grown in the APCS were cultured separately on agar medium containing 0.0, 0.1, 0.3, or 1.0 mg BA/liter with and without 0.1 mg NAA/liter. Isolated fruit grew best on MS medium with BA only and poorest on medium without growth regulators. Chemical names used: N-(phenylmethyl)-1H-purine-6-amine (BA); 1-naphthaleneacetic acid (NAA).
Brent Tisserat and Paul D. Galletta
Some cultivars of mandarin (Citrus reticulata Blanco), sweet orange [Citrus sinensis (L.) Osb.], and trifoliate orange [Poncirus trifoliata (L.) Raf.] were found to have adventitious juice vesicles originating from their exocarp (peel). Several hundred green vesicles may be initiated from curvilinear stylar peel depressions of immature fruit. These vesicles develop similarly to juice vesicles from the endocarp except that, as the fruit matures, exocarp adventitious vesicles die prematurely and degenerate into a fruit surface blemish. Evidence suggests that juice vesicles and oil glands are homologous and merit reconsideration in ontological studies.
Brent Tisserat, Danny Jones, and Paul D. Galletta
Nutrient medium can be sterilized using a household-type microwave oven. The required microwave treatment time was influenced by the oven's microwave power intensity (70 to 700 W), vessel type, volume of medium employed, and the presence of energy sink water reservoirs (ESWR). Growth rates of strawberry (Fragaria vesca L.) shootlets, lemon [Citrus limon (L.) Burm. f.] fruit halves, or carrot (Daucus carota L.) callus cultured on either microwaved or autoclaved media were similar. Microwaving and autoclaving appeared to reduce GA3 activity compared with medium containing filter sterilized GA3. Chemical name used: gibberellic acid (GA3).
Brent Tisserat, Daniel Jones, and Paul D. Galletta
An inexpensive user-constructed ultrasonic misting system to grow plant tissues in vitro is presented. This system is constructed by coupling two commercially available products, a culture chamber and an ultrasonic humidifier. Plant cultures are grown within a culture chamber on a platform and bathed periodically by an ultrasonic nutrient mist. Carrot cultures were found to grow as much as four to 10 times as great as those grown on agar medium.