Secondary Metabolism Inducing Treatments During In Vitro Development of Turmeric (Curcuma longa L.) Rhizomes

Turmeric (Curcuma longa L.) plants that were grown in vitro for 17 or 22 weeks as a fed-batch culture in 2.5 L vessels yielded 39 to 43 g and 62 to 70 g of fresh rhizomes per vessel, respectively (95 % confidence interval). The MS liquid medium was maintained at 6 % sucrose through media addition twice during the experiment. Various methods were employed in attempts to increase secondary metabolism. Antioxidant and total phenolics assays were employed to characterize phytochemical activity. A first experiment exposed four clones to phenylalanine and/or methyl jasmonate (MeJa) from week 12 to 17 in culture. In a second experiment, a clone was given short-term exposure (1.5 weeks) to either proline, a natural proline-rich fish extract, MeJa, or chitosan beginning during the twentieth week of culture. This experiment also included a nitrogen stress treatment (weeks 16–22). The 5-week phenylalanine and MeJa treatments lowered biomass accumulation and antioxidant capacity of the tissue. The magnitude of antioxidant depression was dependent on genotype and, within each genotype, the degree of depression was similar for phenylalanine and MeJa, alone and in combination. In the second experiment, only the low-nitrogen treatment yielded an increase in phenolic content to 4.7 % of dry weight compared to untreated microrhizomes (4.1 % of dry weight). Nitrogen-stressed plants also had less leaf growth, but rhizome mass was unaffected and averaged 63 g FW per vessel. None of the short-term treatments had a significant effect on biomass, antioxidant capacity, or phenolic content. None of the treatments significantly affected radical scavenging, although the low-nitrogen treatment might have improved this activity (p = .1207). Results indicated that plants grown in a high-nitrogen MS media were not responsive to elicitation

Shade and Fertilizer Affects Yield and Quality in a Clonal Plantation of Yaupon Holly

Yaupon holly (Ilex vomitoria Ait.) is the only native American source of caffeinated tea and the small amounts of tea product that is available is currently wild-collected from diverse populations. A clonal field plantation of yaupon was grown under shading and fertilizer treatments and harvested three times in one season to observe changes in yield and phytochemistry. The June and September harvest produced more mass than the July harvest for all treatments. Shading and fertility had interactive effects on increasing fresh mass of the pooled annual harvest, whereas the providing 30% shade and increased fertilizer application (from 567 to 1163 mg/N plant) raised yield 58%. Fertility of 1163 mg/N per plant with 60% shade increased yield another 13% to approximately 1070 kg/ha. This experimental plantation contained 467 plants per ha and was at about half the density of commercial fields (882 plants per ha). Leaves were smaller in July and larger in June and September. Shade greatly increased the leaf size and water content. Caffeine content increased with leaf size over the duration of the experimental treatments and 60% shade treatments in September produced the highest caffeine content (1.21 ± 0.17% of dry mass). In general alkaloids were promoted by shading, and phenylpropanoids were promoted by bright light. This report from one season of observation showed that genetically uniform yaupon holly plantations were manipulated for yield and quality using shade and fertilizer

In vitro mineral nutrition of \u3ci\u3eCurcuma longa\u3c/i\u3e L. affects production of volatile compounds in rhizomes after transfer to the greenhouse

Background Turmeric is a rich source of bioactive compounds useful in both medicine and cuisine. Mineral concentrations effects (PO43−, Ca2+, Mg2+, and KNO3) were tested during in vitro rhizome development on the ex vitro content of volatile constituents in rhizomes after 6 months in the greenhouse. A response surface method (D-optimal criteria) was repeated in both high and low-input fertilizer treatments. Control plants were grown on Murashige and Skoog (MS) medium, acclimatized in the greenhouse and grown in the field. The volatile constituents were investigated by GC-MS. Results The total content of volatiles was affected by fertilizer treatments, and in vitro treatment with Ca2+ and KNO3; but PO43− and Mg2+ had no significant effect. The content was higher in the high-input fertilizer treatments (49.7 ± 9 mg/g DM) with 4 mM Ca2+, 60 mM KNO3 and 5 mM NH4+, than the low-input fertilizer (26.6 ± 9 mg/g DM), and the MS control (15.28 ± 2.7 mg/g DM; 3 mM Ca2+, 20 mM K+, 39 mM NO3−, 20 mM NH4+, 1.25 mM PO43−, and 1.5 mM Mg2+). The interaction of Ca2+ with KNO3affected curcumenol isomer I and II, germacrone, isocurcumenol, and β-elemenone content. Increasing in vitro phosphate concentration to 6.25 mM increased ex vitro neocurdione and methenolone contents. Conclusion These results show that minerals in the in vitro bioreactor medium during rhizome development affected biosynthesis of turmeric volatile components after transfer to the greenhouse six months later. The multi-factor design identified 1) nutrient regulation of specific components within unique phytochemical profile for Curcuma longa L. clone 35–1 and 2) the varied phytochemical profiles were maintained with integrity during the greenhouse growth in high fertility conditions

IBA Delivery Technique and Media Salts Affected In Vitro Rooting and Acclimatization of Eight <i>Prunus</i> Genotypes

Difficult-to-root plants often perform poorly during acclimatization and in vitro rooting can increase the survival and quality of plants. The influence of auxin application and mineral nutrition on in vitro rooting and subsequent effects on plant quality in eight Prunus genotypes were investigated. Microshoots were rooted in vitro on Murashige and Skoog (MS), ½ MS, Driver and Kuniyuki (DKW), or New Prunus Medium (NPM) media formulations in combination with 15 µM indole-3-butyric acid (IBA), 4-day 15 µM IBA pulse, 1 mM 30 s quick-dip, or IBA-free treatments. Shoots were observed pre- and post-acclimatization to determine rooting methods to maximize quality and minimize labor. A genotype-specific response to auxin application was observed with seven of eight genotypes achieving 100% survival when paired with the recommended IBA treatment. Peaches performed best when treated with 4-day IBA pulse or 30 s quick-dip. Rooting of P. cerasifera, it’s hybrid to P. persica, and P. munsoniana all benefitted from IBA application. Shoots rooted with 15 µM IBA were smaller and lower quality in most genotypes. DKW maximized size and quality in six genotypes. Better shoots and larger root systems during in vitro rooting produced better plants in the greenhouse with no detrimental effect of callus growth. Rooting techniques to maximize plant quality while reducing labor are specified

Maximum growth responses for multiplication, fresh biomass and rhizome dry mass were observed in different fed-batch techniques, mineral concentrations and plant densities.

<p>Minerals concentration in milimolar. NSF stands for Nutrients Sucrose Fed-batch; SF stands for Sucrose Fed-batch.</p><p>Maximum growth responses for multiplication, fresh biomass and rhizome dry mass were observed in different fed-batch techniques, mineral concentrations and plant densities.</p

The interaction of plant density and mineral concentrations affected turmeric multiplication ratio.

<p>The response surface plots (with residual data points) shows multiplication ratio of <i>Curcuma longa</i> L. as effected by the interaction of initial plant density (buds/vessel) × Ca concnentraion when other factors were fixed in the nutrient sucrose fed-batch technique, with 6.25 mM P and (a) 20 mM KNO₃ and (b) 60 mM KNO₃.</p

Turmeric fresh biomass (g/vessel) over 22 weeks in treatment conditions.

<p>The response surface plot (plus residual data points) shows <i>Curcuma longa</i> L. fresh biomass (g/vessel) was affected by P × KNO₃ interaction. Other factors in the nutrient sucrose fed-batch technique were fixed with 18 buds/vessel, 3 mM Ca, and 3 mM Mg.</p