Foliar water uptake via cork warts in mangroves of the Sonneratia genus

Foliar water uptake (FWU) occurs in plants of diverse ecosystems; however, the diversity of pathways and their associated FWU kinetics remain poorly resolved. We characterized a novel FWU pathway in two mangrove species of the Sonneratia genus, S. alba and S. caseolaris. Further, we assessed the influence of leaf wetting duration, wet-dry seasonality and leaf dehydration on leaf conductance to surface water (K_surf ). The symplastic tracer dye, disodium fluorescein, revealed living cells subtending and encircling leaf epidermal structures known as cork warts as a pathway of FWU entry into the leaf. Rehydration kinetics experiments revealed a novel mode of FWU, with slow and steady rates of water uptake persistent over a duration of 12 hr. K_surf increased with longer durations of leaf wetting and was greater in leaves with more negative water potentials at the initiation of leaf wetting. K_surf declined by 68% between wet and dry seasons. Our results suggest that FWU via cork warts in Sonneratia sp. may be rate limited and under active regulation. We conclude that FWU pathways in halophytes may require ion exclusion to avoid uptake of salt when inundated, paralleling the capacity of halophyte roots for ion selectivity during water acquisition.

The pomegranate (Punica granatum L.) genome provides insights into fruit quality and ovule developmental biology

Pomegranate (Punica granatum L.) has an ancient cultivation history and has become an emerging profitable fruit crop due to its attractive features such as the bright red appearance and the high abundance of medicinally valuable ellagitannin-based compounds in its peel and aril. However, the limited genomic resources have restricted further elucidation of genetics and evolution of these interesting traits. Here, we report a 274-Mb high-quality draft pomegranate genome sequence, which covers approximately 81.5% of the estimated 336-Mb genome, consists of 2177 scaffolds with an N50 size of 1.7 Mb and contains 30 903 genes. Phylogenomic analysis supported that pomegranate belongs to the Lythraceae family rather than the monogeneric Punicaceae family, and comparative analyses showed that pomegranate and Eucalyptus grandis share the paleotetraploidy event. Integrated genomic and transcriptomic analyses provided insights into the molecular mechanisms underlying the biosynthesis of ellagitannin-based compounds, the colour formation in both peels and arils during pomegranate fruit development, and the unique ovule development processes that are characteristic of pomegranate. This genome sequence provides an important resource to expand our understanding of some unique biological processes and to facilitate both comparative biology studies and crop breeding.

Anatomical explanations for acute depressions in radial pattern of axial sap flow in two diffuse-porous mangrove species: implications for water use

Mangrove species have developed uniquely efficient water-use strategies in order to survive in highly saline and anaerobic environments. Herein, we estimated the stand water use of two diffuse-porous mangrove species of the same age, Sonneratia apetala Buch. Ham and Sonneratia caseolaris (L.) Engl., growing in a similar intertidal environment. Specifically, to investigate the radial patterns of axial sap flow density (Js) and understand the anatomical traits associated with them, we measured axial sap flow density in situ together with micromorphological observations. A significant decrease of Js was observed for both species. This result was accompanied by the corresponding observations of wood structure and blockages in xylem sapwood, which appeared to influence and, hence, explained the acute radial reductions of axial sap flow in the stems of both species. However, higher radial resistance in sapwood of S. caseolaris caused a steeper decline of Js radially when compared with S. apetala, thus explaining the latter's more efficient use of water. Without first considering acute reductions in Js into the sapwood from the outer bark, a total of ~55% and 51% of water use would have been overestimated, corresponding to average discrepancies in stand water use of 5.6 mm day-1 for S. apetala trees and 2.5 mm day-1 for S. caseolaris trees. This suggests that measuring radial pattern of Js is a critical factor in determining whole-tree or stand water use.

Phytobeds with Fimbristylis dichotoma and Ammannia baccifera for treatment of real textile effluent: An in situ treatment, anatomical studies and toxicity evaluation

Fimbristylis dichotoma, Ammannia baccifera and their co-plantation consortium FA independently degraded Methyl Orange, simulated dye mixture and real textile effluent. Wild plants of F. dichotoma and A. baccifera with equal biomass showed 91% and 89% decolorization of Methyl Orange within 60h at a concentration of 50ppm, while 95% dye removal was achieved by consortium FA within 48h. Floating phyto-beds with co-plantation (F. dichotoma and A. baccifera) for the treatment of real textile effluent in a constructed wetland was observed to be more efficient and achieved 79%, 72%, 77%, 66% and 56% reductions in ADMI color value, COD, BOD, TDS and TSS of textile effluent, respectively. HPTLC, GC-MS, FTIR, UV-vis spectroscopy and activated oxido-reductive enzyme activities confirmed the phytotrasformation of parent dye in to new metabolites. T-RFLP analysis of rhizospheric bacteria of F. dichotoma, A. baccifera and consortium FA revealed the presence of 88, 98 and 223 genera which could have been involved in dye removal. Toxicity evaluation of products formed after phytotransformation of Methyl Orange by consortium FA on bivalves Lamellidens marginalis revealed less damage of the gills architecture when analyzed histologically. Toxicity measurement by Random Amplification of Polymorphic DNA (RAPD) technique revealed bivalve DNA banding pattern in treated Methyl Orange sample suggesting less toxic nature of phytotransformed dye products.

Molecular and morphological characterization of pomegranate (Punica granatum L.) genotypes sampled from Coruh Valley in Turkey

The pomegranate is one of the oldest fruits that are traditionally consumed by the local inhabitants of the Coruh Valley, Turkey. In this study, the molecular and morphological characteristics of 19 promising pomegranate genotypes selected from the Coruh Valley were evaluated. For the morphological evaluation, 22 quantitative fruit characteristics were used. For the molecular evaluation, 47 random amplified polymorphic DNA (RAPD) primers were used for polymerase chain reaction analysis. The principle component analysis of 22 quantitative fruit characteristics revealed that fruit weight and skin color are dominant traits for genotype discrimination. The unweighted average distance cluster of fruit characteristics revealed 3 distinct groups. Among the 47 RAPD primers, 9 exhibited reliable polymorphic patterns, and generated a total of 63 RAPD bands, of which 49.2% were polymorphic. The similarity matrix showed that the highest (0.920) and lowest (0.556) genetic similarities occurred between the APS13 and APS28 genotypes and the APS12 and APS42 genotypes, respectively. We determined clear discrepancies between the morphological and molecular data; consequently, the differences obtained among genotypes for fruit characteristics did not support genetic relationships among genotypes. In conclusion, molecular data provided the most reliable results at the DNA level.

Effects of light quality on leaf morphogenesis of a heterophyllous amphibious plant, Rotala hippuris

BACKGROUND AND AIMS

For heterophyllous amphibious plants that experience fluctuating water levels, it is critical to control leaf development precisely in response to environmental cues that can serve as a quantitative index of water depth. Light quality can serve as such a cue because the ratio of red light relative to far-red light (R/FR) increases and blue-light intensity decreases with increasing water depth. Growth experiments were conducted to examine how R/FR and blue-light intensity alter leaf morphology of a heterophyllous amphibious plant, Rotala hippuris.

METHODS

Using combinations of far red (730 nm), red (660 nm) and blue (470 nm) light-emitting diodes (LEDs), growth experiments were used to quantitatively evaluate the effects of the R/FR ratio and blue-light intensity on leaf morphology.

KEY RESULTS

Under the natural light regime in an outside growth garden, R. hippuris produced distinct leaves under submerged and aerial conditions. R/FR and blue-light intensity were found to markedly affect heterophyllous leaf formation. Higher and lower R/FR caused leaf characters more typical of submerged and aerial leaves, respectively, in both aerial and submerged conditions, in accordance with natural distribution of leaf types and light under water. High blue light caused a shift of trait values toward those of typical aerial leaves, and the response was most prominent under conditions of R/FR that were expected near the water surface.

CONCLUSIONS

R/FR and blue-light intensity provides quantitative cues for R. hippuris to detect water depth and determine the developmental fates of leaves, especially near the water surface. The utilization of these quantitative cues is expected to be important in habitats where plants experience water-level fluctuation.

Morpho-physiological and biochemical responses in the floating lamina of Trapa natans exposed to molybdenum

The response to molybdenum (Mo) was studied in the metal-tolerant hydrophyte Trapa natans L. Previously, it was shown that the plant accumulates Mn in the floating lamina by means of phenolic compounds and responded with acclimation responses of the chloroplast. Since the involvement of phenolics has been proposed also in Mo resistance, we tested the response of T. natans to increasing doses (5, 50, 150, 600 microM) of Mo using the photosynthetic apparatus as an indicator of cellular stress. Only 5 microM Mo did not cause evident modifications with respect to controls. Conversely, 50 to 600 microM Mo induced progressively marked alterations of the lamina morphology. The chloroplast ultrastructure showed disorganisation of the thylakoid system, and correspondingly, the photosynthetic pigment pattern was altered with a fall-down in photosynthesis. Microspectrofluorimetry indicated alterations of photosystem II, with differences among the three cell layers (first and second palisade and spongy tissues). While the highest dose caused plant death, 50 and 150 microM Mo-treated plants underwent partial recovery, and the plant survived up to the end of the vegetative season. However, reproduction was unsuccessful. Mo treatment did not induce increase in total phenolics, but only in anthocyanin. In contrast to Mn, detoxification of Mo by chelation inside vacuoles, possibly by anthocyanins, is suggested to be an insufficient mechanism to reduce Mo toxicity, which probably includes an impairment of nitrogen metabolism. However, the metal was accumulated in the lamina. On the whole, T. natans showed limited capabilities to survive Mo excess as compared with Mn.

Rooting response of five pomegranate varieties to indole butyric acid concentration and cuttings age

The purpose of this study was to evaluate the effect of cutting age and Indole Butyric Acid (IBA) treatments on five pomegranate varieties propagation by stem cuttings. The experiment was carried out in a partially controlled glasshouse conditions at Mutah University, Jordan. The treatments comprised of two types of cuttings, i.e., hardwood and semi-hardwood; five concentrations of IBA, i.e., 3,000, 6,000, 9,000 and 12,000 ppm as quick dip (10 sec) as well as five Jordanian pomegranate varieties (Kdaree Hello, Hmadee Hmaree, Kdaree Sfaree, Zeklabi, Maleese). In this study, the percentage of cuttings that rooted, the number of roots produced per cutting, root length and diameter and root weight per cutting were recorded. It was obvious that the rootability of pomegranate is influenced by the interactive effect of cuttings age, IBA concentration and variety as well as by the single effect of either. The cuttings taken from hardwood stems had higher rooting percentage than those taken from semi-hardwood stems with a considerable differences in rootability between varieties under this study. The highest percentage of cuttings that rooted was observed in Hmadee Hmaree (70%), Zeklabee (69%) and Malesse (73%), while the lowest rooting percentage in Khdaree Hello (58%) and Kdaree Sfaree (49%) varieties. Zeklabee and Hmadee Hmaree varieties when compared with other varieties gave more favorable results at 6000 to 9000 ppm IBA in terms of the percentage of cuttings that rooted, the number of roots produced per cutting and root weight per cutting using both semi- and hard-wood cuttings. It was concluded that the increasing dose of IBA could be useful in increasing rooting potential and other root characteristics in pomegranate.

Antimicrobial activity of six pomegranate (Punica granatum L.) varieties and their relation to some of their pomological and phytonutrient characteristics

Arils from six pomegranate (Punica granatum L.) varieties grown in the Mediterranean region of Turkey were tested for their antimicrobial properties by the agar diffusion and minimum inhibitory concentration (MIC) methods against seven bacteria: (Bacillus megaterium DSM 32, Pseudomonas aeruginosa DSM 9027, Staphylococcus aureus Cowan 1, Corynebacterium xerosis UC 9165, Escherichia coli DM, Enterococcus faecalis A10, Micrococcus luteus LA 2971), and threefungi (Kluvyeromyces marxianus A230, Rhodotorula rubra MC12, Candida albicans ATCC 1023). It has been observed that the pomegranate aril extracts had antimicrobial effect on all microorganisms, giving inhibition zones ranging in size from 13 to 26 mm. The MIC values for active pomegranate extracts ranged between 30 and >90 microg/mL. The results obtained appeared to confirm the antimicrobial potential of the Punica granatum varieties.

Influence of methyl jasmonate on inducing chilling tolerance in pomegranate fruits (Malas Save)

Susceptibility to chilling injury in pomegranate is the main limiting factors for storage fruits in low temperature. Inducing chilling tolerance make possible to storage fruits in low temperature for long time. In this study effect of different concentrations of methyl jasmonate (8, 16 and 24 microL L(-1)) as comparison with control on inducing chilling tolerance of pomegranate fruits (Malas Save) was investigated. Qualitative attributes of treated fruits was investigated in different times during low temperature storage and also after transferring that to high temperature as a shelf life. The results showed that methyl jasmonate suppressed chilling injury and water loss and preserved external appearance in pomegranate fruits without abnormal effects on internal fruits quality. In general, with increasing methyl jasmonate concentration, fruits chilling injury reduced significantly. The highest chilling injury index was found in control fruits and the lowest one was for 24 microL L(-1) during storage in low temperature and also after placing in high temperature. Furthermore, no significant differences was found between treated and control fruits for internal fruit characteristics at end of storage.