Tissue Culture Plantlets Research Articles

Use of Tissue Culture Potato Plantlets for Investigations of Diseases of Subterranean Plant Parts

Potato tissue culture plantlets grown in culture tubes were successfully used to establish and monitor disease development in roots and other subterranean plant parts. Host tissue responses to infection and other disease processes were easily observed and received permanently (photographically with or without the aid of a microscope) in a nondestructive manner. Use of this technique for pathogenicity and other investigations is discussed

Modified Sunlight Affects Growth and Flowering of Saintpaulia ionantha H. and Peperomia grisco-argenta Yuncker

Tissue culture plantlets of Saintpaulia ionantha and Peperomia grisco-argenta were grown for 120 days in growth boxes placed in a greenhouse. The filtercovered tops of the boxes were sloped facing south, the direction of the sun, while the walls were constructed of white styrofoam board Four types of light filters covered the frames. Two blue celluloid sheets were used to alter the sunlight spectrum: one filtered out the red (B + FR), and the other removed most of the red and far-red, FR (B - FR). Two polyethylene films were formulated as light filters and diffusers: one scattered all the transmitted light and decreased the R: FR ratio (W), while the other was neutral in respect to the sunlight spectrum and did not cause light scattering (A). Vegetative growth of Saintpaulia plants was enhanced under the light-diffusing filters, resulting in higher fresh weight and larger leaves. Saintpaulia plants flowered first under the W filter, then the A filter, and last under the B + FR filter; no flowering occurred in the absence of FR light (B - RR). There was no significant difference in the development of Peperomia plants grown under the different filters. The results are discussed in relation to plant adaptation to various environments.

Tissue-culture shoot and root system effects on field performance of loblolly pine

To study differences in growth between loblolly pine (Pinustaeda L.) tissue-culture plantlets and seedlings, shoot systems of plantlets and seedlings were grafted onto plantlet and seedling root systems. After three growing seasons, plantlet root systems accounted for 0.3 m of height growth loss and 1.0 cm of loss in basal diameter, while plantlet shoot systems accounted for 0.6 m of height growth loss and 1.4 cm of loss in basal diameter. The mature-appearing morphology of plantlet shoots was due to the shoot system of plantlets and not to the indirect effect of the plantlet root system.

In Vitro Storage of Pineapple (Ananas spp.) Germplasm

Sterile distilled water was found to be an acceptable medium for the maintenance of tissue-cultured plantlets of three Ananas accessions. Eighty-one percent of the plantlets survived 12 months at 25C in 1 ml of sterile distilled water. Plantlets stored in water for 12 months were observed to be more vigorous than those that were cultured for 12 months in full-strength Murashige and Skoog (MS) medium. However, medium containing l/4-strength MS salts and full-strength organics, 3% sucrose, and agar gave the best plant survival and vigor. None of the plantlets in this study produced callus. Only a single instance of axillary budbreak was observed in explants stored on the l/4-strength MS medium.

The effect of root pruning on the maturation of loblolly pine (Pinustaeda) plantlets, rooted hypocotyls, and seedlings

Loblolly pine (Pinustaeda L.) tissue culture plantlets, seedlings, and rooted hypocotyls were subjected to three root-pruning treatments (control, half apices pruned, all apices pruned) to determine if pruning could alter the maturation state of the shoots, and if there was a correlative alteration of shoot cytokinin levels. Height, multiple characteristics of shoot morphology correlated with maturation, and root morphology were assessed. In comparisons with control plantlets, pruning significantly decreased plant height in half-pruned and all-pruned plantlets, needle length in all-pruned plantlets, terminal bud length and diameter in half-pruned and all-pruned plantlets, and needle dry weight in half-pruned plantlets. When these shoot morphological characteristics were regressed against height, the half-pruned plantlets appeared more juvenile than controls for both terminal bud length and diameter. All-pruned plantlets did not differ from controls. In comparisons of the three intact plant types, the plantlets were more mature than seedlings and rooted hypocotyls based on assessments of terminal bud length, terminal bud diameter, and needle length. However, in the half-pruned treatment these three characteristics did not differ among plantlets, seedlings, and hypocotyls, showing that they were equivalent for maturation status. Root pruning significantly increased the number of root apices for all plant types but did not increase plantlet or rooted hypocotyl cytokinin levels.

FIELD ESTABLISHMENT OF TISSUE-CULTURED `HERITAGE' RED RASPBERRY

Tissue-cultured (TC) plantlets are gaining wide acceptance as the standard transplanting stock within both the fruit and nursery industry. However, research and grower experiences suggest that management practices used for conventionally propagated raspberry plants may need to be tailored for successful field establishment of the TC plantlet. The effects of weed control practices, rowcovers, and fertilizer placement on the performance of newly planted TC `Heritage' red raspberry were evaluated during two years. Weed control treatments included straw mulch (ST), black polyethylene mulch (B), white on black polyethylene mulch (WB), napropamide herbicide (N), simazine herbicide (S), hand-weeding (HW), and an untreated control (U). Rowcovers were used during the first six weeks of establishment on the mulched and hand-weeded treatments. Calcium nitrate was placed in the planting hole or on the soil surface around the plant. Second year yields were directly proportional to soil moisture levels during the summer of the planting year. Plants mulched with ST, B, or WB during the planting year produced greater early yields during the fruiting year. Primocane density was highest in the ST treatment. Rowcovers consistently increased both soil temperature and soil moisture, but tended to cause a reduction in cane length the first growing season. Fertilizer placement had no consistent effect on any measured variable.

TISSUE-CULTURED RASPBERRY PLANT ESTABLISHMENT

Tissue-cultured (TC) plantlets are becoming the preferred planting stock for raspberry growers because of their uniformity, ease of handling, general vigor and disease status. However, previous studies have shown that TC plants are sensitive to many preemergent herbicides and to cultivation within several weeks after planting. ln addition, little is unknown about handling practices for TC plants relative to conventionally propagated plants during the establishment year. We subjected TC raspberries cv. Heritage to different management practices during the establishment year and monitored plant performance over two years to determine if better recommendations could be made for TC plantlets. One set of management practices examined weed control, and treatments included straw mulch, black polyethylene mulch, white on black polyethylene match, napropamide herbicide, simazine herbicide, hand weeding, and an untreated control. A second factor was fertilizer placement, with calcium nitrate applied on the soil surface around the plant or placed in the planting hole. A third factor was row cover application during the first six weeks of growth. Significant differences in soil moisture, soil temperature, plant growth, and yield occurred among the 22 treatments, and results suggested that TC plants require a different set of management practices than conventional propagules.

Growth of Transplants and in Vitro-cultured Clones of Asparagus in Response to CO2 Enrichment and Supplemental Lighting

Asparagus (Asparagus officinalis L.) transplants and in vitro-cultured clones were grown and acclimatized under two photosynthetic photon flux (PPF) conditions (ambient and ambient + 80 μmol·s-1·m-2) and three atmospheric CO2 concentrations (330, 900, and 1500 ppm). Short- and long-term effects were measured in the greenhouse and after two seasons of growth in the field, respectively. In the greenhouse, CO2 enrichment (CE) and supplemental lighting (SL) increased root and fern dry weight by 196% and 336%, respectively, for transplants and by 335% and 229%, respectively, for clones. For these characteristics, a significant interaction was observed between SL and CE with tissue-cultured plantlets. In the absence of SL, CE did not significantly increase root or shoot dry weight. No interaction was observed between CE and SL for transplants, although these factors significantly improved growth. It was possible to reduce the nursery period by as much as 3 weeks with CE and SL and still obtain a plant size comparable to that of the control at the end of the experiment. Long-term effects of SL were observed after two seasons of growth in the field. Supplemental lighting improved survival of transplants and was particularly beneficial to in vitro plants. Clones grown under SL were of similar size as transplants after 2 years in the field.

Evaluation of Preemergent Herbicide Phytotoxicity to Tissue, Culture-propagated `Heritage' Red Raspberry

Five greenhouse and two Geld experiments were conducted to evaluate tissue culture-propagated (TC) raspberry (Rubus idaeus cv. Heritage) sensitivity to preemergent herbicides. Plant performance was measured by plant vigor, above-ground fresh weight, root development, and primocane number. Simazine and oryzalin caused significant injury to newly planted TC raspberry plants in greenhouse and field experiments. The severity of injury was generally linear with respect to herbicide rate, but no appreciable differences in injury were observed between the granular and spray applications. Napropamide wettable powder caused some foliar injury, but plants recovered within one growing season and growth was equal or superior to the hand-weeded controls. The granular formulation of napropamide produced similar results, but did not cause the initial foliar burn. Pre-plant dipping of roots into a slurry of activated carbon did not prevent simazine or oryzalin injury, but injury was reduced when herbicide applications were delayed. Simazine applied 4 weeks after planting was not Injurious, and oqzalin applied 2 or 4 weeks after planting caused some foliar injury, hut no reduction in plant fresh weight. Delayed treatments of napropamide increased foliar injury. Herbicide tolerance of tissue-cultured plantlets appeared to be less than that of conventionally propagated plants. Chemical names used: N,N-diethyl-2-(1-napthalenyloxy)propanamide (napropamide), 4-(dipropylamino)-3,5-dinitrobenzenesulfonamide (oryzalin), 6-chloro-N,N'diethyl-1,3,5-triazine-2,4-diamine (simazine).

Juvenile wood specific gravity of loblolly pine tissue culture plantlets and seedlings

Juvenile-wood specific gravity of loblolly pine (Pinustaeda L.) tissue culture plantlets and seedlings were compared. Wood samples collected from several (6 to 13) families at three sites, each at a different age (2, 3, and 6 years), showed a significant difference between the overall plantlet and seedling mean specific gravity only in the youngest material (0.387 versus 0.356, respectively). Another collection of wood samples from three different sites at age 5 years showed that the within-site variation in specific gravity for a single clone was 29% that of the open-pollinated family from which it was derived. When tissue culture techniques become practical, operational clonal plantations of loblolly pine should offer substantial improvement in the uniformity of wood produced relative to the heterogeneous seedling-origin plantations currently being established.

Pruning Responses of Tissue-Cultured Plantlets of Rhododendrons

Abstract Plantlets of Rhododendron ‘Molly Ann’, R. ‘Paprika Spiced’, and R. ‘Travis L.’, recently rooted from tissue culture, were grown in a greenhouse in individual containers. Plants pruned by pinching, top-pruning, or root-pruning were compared to unpruned plants. Growth, as measured by shoot height, shoot dry weight, root dry weight, and stem caliper, was generally reduced by pruning. Top-pruning and pinching induced branching in all cultivars tested and improved stem taper (ratio of basal to upper caliper) in two cultivars, including R ‘Travis L.’, which is particularly prone to develop weak stems when produced by tissue culture.

A Rapid Clearing and Staining Method for Tissue-cultured Plantlets and Greenhouse-grown Leaves

Abstract A simple, rapid clearing and staining method was developed using intact in vitro blackberry (Rubus spp. ‘Silvan’) and strawberry (Fragaria × ananassa Duch. ‘Totem’) plantlets and sections of greenhouse-grown ‘Silvan’ and ‘Totem’ leaves. The clearing method involved three steps: 1) autoclaving in 80% ethanol to remove the chlorophyll, which took 15 to 20 min for plantlets and 25 and 35 min for greenhouse-grown ‘Silvan’ and ‘Totem’, respectively; 2) dissolution of the protoplasm using 5% NaOH at 80°C, which took 20 min for plantlets and 35 and 40 min for greenhouse-grown ‘Silvan’ and ‘Totem’ respectively; 3) post-alkali treatment with 75% bleach (4.5% NaClO). For tissue-cultured plantlets this took 5 to 10 min at room temperature, but greenhouse-grown material required 35 to 40 min at 55°. Aqueous safranin (10 mg·liter−1) was used for staining. This method gave consistently good results and required a maximum of 2 hr for completion.

Cultural systems for growing potatoes in space.

Higher plants are being evaluated for life support to provide needed food, oxygen and water as well as removal of carbon dioxide from the atmosphere. The successful utilization of plants in space will require the development of not only highly productive growing systems but also highly efficient bioregenerative systems. It will be necessary to recycle all inedible plant parts and all human wastes so that the entire complement of elemental compounds can be reused. Potatoes have been proposed as one of the desirable crops because they are 1) extremely productive, yielding more than 100 metric tons per hectare from field plantings, 2) the edible tubers are high in digestible starch (70%) and protein (10%) on a dry weight basis, 3) up to 80% of the total plant production is in tubers and thus edible, 4) the plants are easily propagated either from tubers or from tissue culture plantlets, 5) the tubers can be utilized with a minimum of processing, and 6) potatoes can be prepared in a variety of different forms for the human diet (Tibbitts et al., 1982). However potatoes have a growth pattern that complicates the development of growing the plants in controlled systems. Tubers are borne on underground stems that are botanically termed 'rhizomes', but in common usage termed 'stolons'. The stolons must be maintained in a dark, moist area with sufficient provision for enlargement of tubers. Stems rapidly terminate in flowers forcing extensive branching and spreading of plants so that individual plants will cover 0.2 m2 or more area. Thus the growing system must be developed to provide an area that is darkened for tuber and root growth and of sufficient size for plant spread. A system developed for growing potatoes, or any plants, in space will have certain requirements that must be met to make them a useful part of a life support system. The system must 1) be constructed of materials, and involve media, that can be reused for many successive cycles of plant growth, 2) involve a minimum quantity of media, 3) contain media that is essentially inert and not oxidize or degrade with use, 4) utilize a recirculating nutrient solution to permit regulation of pH and nutrient concentrations, and 5) be capable of complete automation of all planting, maintenance and harvesting procedures.

準備ステージにある培養カーネーション (<i>Dianthus caryophyllus</i> L.) 小植物体の生長におよぼす強光下炭酸ガス施用と培地ショ糖濃度の影響

Explants of tissue-cultured carnation (Dianthus caryophyllus L.) plantlets were cultured in preparation for growth during the acclimatization stage. Plantlets werecultured in glass test tubes with plastic formed caps in a room with CO2 concentration of 1000-1500vpm and a photosynthetic photon flux of 150μmol m-2s-1 (400-700nm). The effects of the sucrose concentration in the medium on the plantlet growth were also examined under the above mentioned culture conditions.The plantlet growth was promoted, to a large extent, by CO2 enrichment under high photon flux. The order of largest to smallest of fresh and dry weight increases of the plantlets during the culture was CO2 enriched treatment with 1% sucrose, CO2 enriched treatment with 0% sucrose, CO2 enriched treatment with 2% sucrose, CO2 nonenriched treatments with 2% sucrose, 1% sucrose, and 0% sucrose. Plantlets grew autotrophically by CO2 enrichment with high photon flux.The net photosynthetic and dark respiration rates of the plantlets and the dry weight decreases in total sugar and nutrient salts in the medium were estimated to explain the differences in the dry weight increase of the plantlets in the various treatments. The implications of the results for developing a new mass propagation system of tissue-cultured plantlets are discussed.

A Method for Estimating CO2 Exchange Rates of Tissue-cultured Plantlets in vitro for a Constant CO2 Concentration in Culture Vessels with Time

A Method for Estimating CO2 Exchange Rates of Tissue-cultured Plantlets in vitro for a Constant CO2 Concentration in Culture Vessels with Time

Root histology, and nutrient uptake and translocation in tissue culture plantlets and seedlings ofThuja occidentalis L.

Histological studies of the vascular connection in the root-shoot junction of tissue culture-derived plantlets and seedlings ofThuja occidentalis L. (Eastern white cedar) showed that in both plant types the xylem was well developed, smooth and not disrupted. Uptake and translocation of32P and86Rb were also similar for plantlets and seedlings. However, approximately 50% more86Rb could be desorbed from the root Donnan free space of plantlets than from seedlings. Uptake and translocation to the shoot was higher for86Rb than for32P, but no differences were found between the plant types. Tracer translocation rates to the shoot seem to be positively correlated with shoot fresh weight.

Freeze Preservation of Apical Meristems of Rubus in Liquid Nitrogen

Abstract Shoot tip explants from tissue culture plantlets of five Rubus accessions (Rubus leucodermis Torr. & Gray, R. spectabilis Pursh, R. idaeus L. ‘Heritage’, Rubus spp. ‘Logan Thornless’ and ‘Merton Thornless’) were frozen slowly (0.8°C/min) to -40° and then rapidly to -196° in the presence of cryoprotectants. Following rapid thawing, regrowth as organized apical growth or as callus occurred on agar media. A combination of polyethylene glycol (PEG), glucose, and dimethylsulfoxide (PGD) was the most successful cryoprotectant.

In vitro reactions of sugarcane (Saccharum SP.) plantlets inoculated with 2 strains of Xanthomonas albilineans (Ashby) Dowson

The symptoms of the leaf scald disease can be reproduced in vitro through the inoculation of sugarcane tissue culture plantlets. The pathogen is detected in the inoculated plantlet and is maintained at the surface of the base of the plantlets grown in vitro. Two strains of X. albilineans belonging to different serovars and lysovars reacted like pathotypes. The importance of the plant incubation temperature is clearly demonstrated. Further, in vitro the disease goes through the same phase of latency as in the field.

Early Shoot and Root Quality Effects on Nursery and Field Development of Tissue-cultured Loblolly Pine

Abstract Height, number of roots, root length, and shoot quality rating on loblolly pine (Pinus taeda L.) tissue culture plantlets were measured in the laboratory and related to subsequent nursery and field performance. Shoot quality rating was the most important characteristic and was most consistently correlated with nursery and field traits. These results imply that only plantlets with the best shoot quality rating should be used so that growth rates will be similar to seedlings.

Economic Analysis of the Use of Tissue Culture for Rapid Forest Improvement

The economic feasibility of the use of tissue culture in forestry for planting stock production depends on two main conditions. One is the ability to produce sufficient genetic gain in a breeding program through controlled crosses, while the other depends on the utilization of the genetic gain (i.e. increased growth rate) to reduce rotation age. The cost of tissue culture plantlets will be relatively high, but will be more than compensated by the savings realized due to a shorter growth period.