Brent Tisserat

Phenolic composition of various tissues of rutaceae species

Abstract A survey of phenolic compounds using HPLC was performed in Rutaceae, subfamily Aurantioideae, representing five genera, 35 species and 114 cultivars. T

Development of an automated plant culture system

An apparatus was constructed that could be used to grow plant tissues, organs, and whole plantlets under sterile conditions. This system accommodated independent or multiple concurrent growth of cultures. Growth of plants either equalled or exceeded that observed using the manual transfer procedure. The automated plant culture system (APCS) consists of silicone tubing, 2 impeller pumps, 2 glass medium reservoir bottles, a 3-way stainless steel valve, a plant culture chamber, and an interface module containing relay boards. Control of the APCS is through interfacing with a microcomputer (e.g. Apple IIe or Atari 400). The computer controlled medium introduction, evacuation, and replenishment in a sterile environment. The APCS was inexpensively constructed and provides a labor-saving, long-term method to culture plants in vitro.

Factors involved in the production of plantlets from date palm callus cultures

SummaryA discussion of a suitable procedure to rapidly propagate free-living date palms (Phoenix dactylifera L.) from callus cultures is presented. Embryogenic callus derived from lateral bud explants was subjected to various auxin treatments in liquid and agar media including p-chlorophenoxyacetic acid. α-naphthaleneacetic acid or 2,4-dichlorophenoxyacetic acid at 0.0, 0.1, 1.0 and 10.0 mg/l concentrations in order to obtain optimum growth. Subsequent plantlet initiation from callus was found to be related to initial auxin pretreatments upon subculture to medium devoid of hormones. Plantlet production from callus subcultured from media containing 0.0, 1.0 and 10.0 mg/l auxin concentrations was notably lower than from callus precultured on the 0.1 mg/l auxin levels. In order to improve in vitro adventitious rooting isolated plantlets were cultured on media containing 0.0, 0.1, 1.0 and 10.0 mg/l concentrations of indole-3-acetic acid or α-naphthaleneacetic acid in various physical environments. Optimum adventitious rooting responses and survival in free-living conditions were obtained by culturing plantlets in medium containing 0.1 mg/l for 8–16 weeks prior to transplanting to soil. Axillary shoot outgrowths (offshoots) were found to be common in plantlets cultured on a variety of media once an adequate root-shoot system was developed. Mention of a trademark name or proprietary product does not constitute a guarantee or warranty of the product by the US. Department of Agriculture and does not imply its approval to the exclusion of other products that may be suitable.

Flavonoid changes in developing lemons grown in vivo and in vitro

Abstract Concentrations and HPLC profiles of the major flavonoids of lemon juice vesicles ( Citrus limon cv. Eureka) were determined for tree-grown fruit 2–55 mm diameter and in 25–30 mm diameter fruit halves cultured in vitro for up to four months. In tree-grown fruit, the total amount of hesperidin per lemon accumulates rapidly from fruit set to its maximum value at the 25–30 mm diameter stage; and thereafter the concentration continually decreases as the fruit increases in diameter. At the 25–30 mm stage, the total amount of eriocitrin begins to increase rapidly and continues until the fruit reaches full size. The amount of diosmin per fruit increases gradually throughout the development of the lemon. Flavonoids of juice vesicles from in vitro cultured fruit halves show a pattern of development similar to fruit grown on the tree. In contrast, flavonoid patterns from callus derived from juice vesicles were quite dissimilar to those of developing fruit.

In vitro flowering from Citrus limon lateral buds.

Summary Citrus limon (L.) Burm. f. cv. «Eureka» vegetative lateral buds from 6-year old trees, when cultured at 14 to 20 °C in vitro , flower at rates of 5 to 20 % after 16 weeks and 90 % within 32 weeks. Buds maintained at 25 °C did not flower, and attempts to chemically induce flowering at 25 °C using various growth inhibitors and promoters as well as high concentrations of sugars failed. Abscission of floral and foliar buds, as well as leaves, was common in vitro .

Production of Pharmaceuticals from Papaver Cultivars in Vitro

Iranian (Papaver bracteatum Lindl.) and opium poppy (P. somniferum L.) plantlets obtained from germinated seeds grown on a Murashige and Skoog basal medium (BM) readily manifest alkaloids. Temperature had a profound effect on growth and alkaloid production after 8 weeks in culture. Plantlets of poppy cultivars (cvs.) grew best at 18.5 and 20°C compared to 15 or 25°C. An alkaloid survey study with 24 Iranian and 21 opium poppy cvs. revealed that total morphinan alkaloids ranged from 0 to 6.55 mg/g dw. Prolific axillary branching was achieved from poppy cvs. by maintaining shoots on BM containing 1.0 mg/L N6‐benzyladenine and 0.01 mg/L α‐naphthalene acetic acid for an additional 16 weeks. The influence of vessel size on the growth response of established shoot clumps was determined by subculture in a variety of culture vessels for 8 weeks. The tested culture vessels included culture tubes (55 mm3 capacity (cap.)), babyfood jars (143 mm3 cap.), Magenta GA‐7 containers (365 mm3 cap.), and polycarbonate jars (1890 mm3 cap.) employing an in vitro hydroponics system (i.e. an automated plant culture system (APCS)). Highest growth rates occurred employing the APCS. The culture vessel capacity had a significant positive correlation on shoot length, fresh weight, number of leaves, and number of shoots. Shoot length, fresh weight, leaves, and shoots grown in the APCS exhibited increases of 1‐, 21.5‐, 7.8‐, and 8.3‐fold, respectively, compared to shoots grown in culture tubes. Higher culture growth rates that occurred in the larger‐size vessels were correlated with lower alkaloid production (mg alkaloids/g dw). However, the overall total alkaloids/vessel [(mg alkaloid/g dw)×g culture dw] increased because of greater biomass production per vessel. The alkaloid content was found to remain stable for shoots grown over a 6–month evaluation period.

Root responses of sterile-grown onion plants to iron deficiency

Abstract Onion (Allium sativum) plants grown without iron (Fe) in sterile nutrient solutions readily developed chlorosis symptoms. Iron deficiency in the sterile‐grown plants stimulated the rates of root extracellular reduction of Fe3+, copper (Cu2+), manganese (Mn4+), and other artificial electron acceptors. While rapid reduction occurred with the synthetic chelate Fe3+HEDTA, no short‐term reduction occurred with the fungal siderophore Fe3+ferrioxamine B (FeFOB). In addition to the increased rate of extracellular electron transfer at the root surfaces, the Fe‐deficient plants showed greater rates of Fe uptake and translocation than the onion plants grown with Fe. The rates of uptake and translocation of Fe were sharply higher for the Fe‐deficient plants supplied with FeHEDTA than for similar plants supplied with FeFOB. Inhibition by BPDS of the Fe uptake by the Fe‐deficient onion plants further supported the importance of Fe3+ chelate reduction for the uptake of Fe into the roots. Rates of Fe uptake and ...

Morphogenetic responses obtained from a variety of somatic explant tissues of date palm

Shoot tip, bud, leaf, stem and root explants from bearing trees, offshoots, seedlings, and asexual plantlets ofPhoenix dactylifera L. were cultured on modified Murashige and Skoog nutrient media containing 3 g/l activated charcoal, 100 mg/l 2,4-dichlorophenoxyacetic acid, 3 mg/lN6-(Δ2-isopentyl)adenine to obtain callus. Differential morphogenetic responses were obtained from calli dependent on the explant type and parent source. Subcultured shoot tips and leafy lateral buds callus on nutrient media devoid of charcoal and supplemented with 0.1 mg/l α-naphthaleneacetic acid (NAA) produced adventitious plantlets. Subcultured leaf calli produced roots only. Root callus failed to exhibit any morphogenetic response upon subculturing. Undifferentiated non-leafy buds and stem tissues did not give rise to callus, regardless of the parent source. Generally, the best callus and embryogenetic responses from explants were obtained from seedling and plantlet parent sources. Similarly, organogenetic responses such as root formation and shoot development from shoot tips cultured on media containing 10 mg/l NAA were also related to the parent explant source.

Interactions of culture vessels, media volume, culture density, and carbon dioxide levels on lettuce and spearmint shoot growth in vitro

Abstract The influence of culture chamber capacity, medium volume and culture density on the growth yields of lettuce (Lactuca sativa L.) and spearmint (Mentha spicata L.) shoots were determined in an environment containing either 350 or 10,000 μmol mol–1 CO2 after 8 weeks of incubation. High positive correlations occurred between the culture vessel capacity and spearmint fresh weight, leaf number, root number, and shoot number. Similarly, high positive correlations occurred between culture vessel capacity and lettuce fresh weight, leaf number, and root number. Higher fresh weights, leaf numbers, and root numbers were obtained from lettuce and spearmint shoots when cultured in 1-quart Mason jars containing 100- or 150-ml aliquots of medium compared to jars containing 25- or 50-ml aliquots of medium within an environment containing either 350 or 10,000 μmol mol–1 CO2. High culture density decreased growth yields, and this phenomenon could only be slightly off-set by the employment of an elevated CO2 environment or larger culture vessels.

Production of cucumber fruits from the culture of ‘Marketmore-76’ plantlets

A procedure to produce fruits from cultured shoot tips of Cucumis sativus L. cultivar ‘Marketmore-76’ in vitro is described. Four-week-old shoot tips, derived from sterile germinated seedlings on a MS medium, were cultured in a 3.8-1 Mason jar using an automated plant culture system. Tips readily generated roots, leaves and flowers after another 4 to 8 weeks in culture. Administration of compressed air at a 300 ml/min flow rate for 30 min 10 or 15 times a day induced the development of parthenocarpic fruits from flowers. Fruits, up to 170 mm long by 35 mm diameter, were obtained within 30 to 45 d after flower opening.