Kappaphycus malesianus sp. nov.: a new species of Kappaphycus (Gigartinales,Rhodophyta) from Southeast Asia

A new species, Kappaphycus malesianus, is established as a new member of the genus Kappaphycus. Locally known as the “Aring-aring” variety by farmers in Malaysia and the Philippines, this variety has been commercially cultivated, often together with Kappaphycus alvarezii due to the similarities in morphology. Despite also producing kappa-carrageenan, the lower biomass of the K. malesianus when mixed with K. alvarezii ultimately affects the carrageenan yield. Morphological observations, on both wild and cultivated plants, coupled with molecular data have shown K. malesianus to be genetically distinct from its Kappaphycus congeners. The present study describes the morphology and anatomy of this new species as supported by DNA data, with additional morphological features for distinguishing between commercial Kappaphycus cultivars.     

Genetic diversity of Kappaphycus Doty and Eucheuma J. Agardh (Solieriaceae,Rhodophyta) in Southeast Asia

The commercial importance of carrageenophytes Kappaphycus and Eucheuma is well known, with much interest in terms of cultivation, marketing, and research. Considering the many lucrative prospects, these red seaweeds were introduced into various parts of the world for farming, where merely a few were comprehensively documented. Despite being extensively cultivated throughout Southeast Asia, the genetic diversity of Kappaphycus and Eucheuma is poorly studied, where heavy reliance is placed on the use of local or commercial names for identifications. This study used the mitochondrial-encoded cox1 and cox2–3 spacer genetic markers to investigate the Kappaphycus and Eucheuma haplotypes, cultivated and wild, available throughout Southeast Asia. Concatenated cox1–cox2–3 spacer datasets were also analyzed. The near full-length cox1 gene is preferred at revealing the genetic diversity of Kappaphycus and Eucheuma, provided a larger reference database is available. Both molecular markers were capable of delineating common members of the genus Kappaphycus (i.e., Kappaphycus alvarezii, Kappaphycus striatus, and Kappaphycus cottonii) and Eucheuma denticulatum, and revealed interesting genotypes and new species which may be potential alternatives to the common cultivars as well as materials for research. The relative scarcity of Eucheuma species is discussed and future sites for sampling are recommended.     

Bioremediation potential of three carrageenophytes cultivated in tanks with seawater from fish farms

Intensive fish farming discharges large amount of nutrients, the majority of which are composed of dissolved nitrogen in ammonium form, which promotes eutrophication in coastal waters. Macroalgae have been proven to effectively reduce the nutrients of fish farm effluents and at the same time increase the economic output of the aquaculture system when economically important species are utilized. In this study, the potential of three high value carrageenophytes (Kappaphycus alvarezii, Kappaphycus sp., K. striatum) to extract ammonium in fish farm effluent collected from a milkfish (Chanos chanos) fish cage was investigated. To establish economic viability of the integrated culture system, the effects of elevated total ammonia of fish farm effluent on the growth rate, phycocolloid content, and quality of these seaweeds were determined. Tank cultivation trials showed that the three carrageenophytes substantially reduced the ammonium content of the fish farm effluent (41–66% reduction efficiency) and consequently attained maximum daily growth rates of 4.41%, 2.90%, and 2.75% for K. striatum, Kappaphycus sp., and K. alvarezii, respectively. Their carrageenan content was improved. Carrageenan quality, however, was not significantly enhanced. Elevated ammonium in fish farm effluent did not adversely affect the performance of tank cultivated Kappaphycus; thus, future integration of these seaweeds in fish farms is feasible. Presented at the 6th Meeting of the Asian Pacific Society of Applied Phycology, Manila, Philippines.     

Impact of AMPEP on the growth and occurrence of epiphytic Neosiphonia infestation on two varieties of commercially cultivated Kappaphycus alvarezii grown at different depths in the Philippines

Two varieties of the carrageenophyte Kappaphycus alvarezii (Tungawan, TUNG; and Giant tambalang, GTAM) from Zamboanga Sibugay, Philippines were used to test the efficacy of Acadian Marine Plant Extract Powder (AMPEP) as source of nutrients for growth, and to determine if applications had any effect on the percent occurrence of an epiphytic infestation of the red alga Neosiphonia sp. at four different depths in the sea. Results showed that the use of AMPEP significantly (P < 0.05) increased the growth rate of both Kappaphycus varieties tested but decreased the percent occurrence of Neosiphonia sp. The percent occurrence of Neosiphonia sp. infection (6–50% at all depths) of both Kappaphycus varieties with AMPEP treatment was significantly lower than the controls (i.e., 10–75% at all depths). Both the growth rate of the cultivated seaweed and the percent occurrence of the epiphytes decreased as the cultivation depth increased. Plants dipped in AMPEP and suspended at the surface had the highest growth rates (i.e., 4.1%, TUNG; 3.1%, GTAM) after 45 days; those without AMPEP dipping had the highest percent occurrence of Neosiphonia infection (viz. 70–75%). The occurrence of Neosiphonia infestation was found to be correlated with changes in irradiance and salinity at the depths observed. The results suggested that both varieties of K. alvarezii used in this study have the fastest growth rate when grown immediately at the water surface. However, in order to minimize damage caused by the occurrence of epiphytic Neosiphonia, K. alvarezii should be grown within a depth range of 50–100 cm. These observations are important for the improved management of Kappaphycus for commercial farming. Furthermore, the use of AMPEP treatments for enhancement of growth and reduction deleterious Neosiphonia sp. infections is encouraging.     

Occasional pathogenic bacteria promoting ice-ice disease in the carrageenan-producing red algae Kappaphycus alvarezii and Eucheuma denticulatum (Solieriaceae,Gigartinales, Rhodophyta)

The bacterial isolates from normal and diseased branches of Kappaphycus alvarezii and Eucheuma denticulatum in the Philippines were examined for possible role in the development of the ice-ice disease. The numbers of bacteria on and in ice-iced branches were 10–100 times greater than those from normal, healthy ones. Gram-positive bacteria predominated in almost all branch sources, but with an increasing proportion of agar-lysing bacteria in branches suffering from the ice-ice disease. These agar-lysing bacteria were composed of yellow and non-pigmented, spreading colonies identified to the Cytophaga-Flavobacterium complex and the Vibrio group. Among isolates which mainly appeared on ice-iced branches, two strains, designated as P11 (Vibrio sp.) and P25 (Cytophage sp.), which showed pathogenic activity, were obtained. These strains caused early ice-ice whitening of K. alvarezii especially when subjecting branches to environmental stress, such as reduced salinity and light intensity, suggesting that these bacteria were occasionally pathogenic. This paper offers new evidence of bacterial role in the development of so-called ice-ice disease among farmed species of Kappaphycus.     

A molecular method for identification of the morphologically plastic invasive algal genera Eucheuma and Kappaphycus (Rhodophyta, Gigartinales) in Hawaii

A paucity of diagnostic morphological characters for identification and high morphological plasticity within the genera Eucheuma and Kappaphycus has led to confusion about the distributions and spread of three introduced eucheumoid species in Hawaii. Entities previously identified as E. denticulatum, K. alvarezii, and K. striatum have had profound negative effects on Oahu’s coral reef ecosystems. The use of molecular tools to aid identification of algal species has been promising in other morphologically challenging taxa. We used three molecular markers (partial nuclear 28S rRNA, partial plastid 23S rRNA, and mitochondrial 5′ COI) and followed a DNA barcoding-like approach to identify Eucheuma and Kappaphycus samples from Hawaii. Neighbor-joining analyses were congruent in their separation of Eucheuma and Kappaphycus, and the resulting clusters were consistent with those revealed for global comparisons with the mitochondrial cox2-3 spacer and GenBank data. Based on these results, new insights were revealed into the distribution of these groups in Hawaii.     

Systematics and genetic variation in commercial shape Kappaphycus and shape Eucheuma (Solieriaceae, Rhodophyta)

The systematics and taxonomy of Kappaphycus and Eucheuma (Solieriaceae) is confused and difficult due to morphological plasticity, lack of adequate characters to identify species and commercial names of convenience. These taxa are geographically widely dispersed through cultivation. Commercial, wild and herbarium sources were analysed; molecular markers provided insights into taxonomy and genetic variation, and where sources of genetic variation may be located. The mitochondrial cox2-3 and plastidal RuBisCo spacers were sequenced. There is a clear genetic distinction between K. alvarezii (“cottonii”) and K. striatum (“sacol”) samples. Kappaphycus alvarezii from Hawaii and some samples from Africa are also genetically distinct. Our data also show that all currently cultivated K. alvarezii from all over the world have a similar mitochondrial haplotype. Within Eucheuma denticulatum (“spinosum”) most African samples are again genetically distinct. Our data also suggest that currently cultivated E. denticulatum may have been “domesticated” several times, whereas this is not evident for the cultivated K. alvarezii. The present markers used do not distinguish all the morpho-types known in cultivation (e.g. var. tambalang, “giant” type) but do suggest that these markers may be useful to assess introductions and species identification in samples.     

The commercial red seaweed <Emphasis Type="Italic">Kappaphycus alvarezii</Emphasis>—an overview on farming and environment

Commercial cultivation of the red alga Kappaphycus alvarezii (Doty) Doty has been satisfying the demand of the carrageenan industry for more than 40 years. For the past four decades, this species has been globally introduced to many maritime countries for experimental and commercial cultivation as a sustainable alternate livelihood for coastal villagers. Accompanying the introduction is an increasing concern over the species effects on the biodiversity of endemic ecosystems. The introductions of non-endemic cultivars have resulted in the adaptation of quarantine procedures to minimize bioinvasions of additional invasive species. The present review focuses on Kappaphycus farming techniques through the application of biotechnological tools, ecological interactions with endemic ecosystems, future K. alvarezii farming potentials in Asia, Africa, and the Pacific, and the challenges for prospective farmers, i.e., low raw material market value, diseases, grazing, etc. The introduction of Kappaphycus cultivation to tropical countries will continue due to the high production values realized, coastal villages searching for alternative livelihoods, and the increased global industrial demand for carrageenan.     

Hybridization and phylogeography of the Mozambique tilapia <Emphasis Type="Italic">Oreochromis mossambicus</Emphasis> in southern Africa evidenced by mitochondrial and microsatellite DNA genotyping

Many Oreochromis species utilized in aquaculture were extensively introduced outside their native range in Africa. Given their recent evolutionary radiation, these species hybridize easily, posing a threat to the integrity of local adaptation. The objective of this work was to study the genetic diversity of the Mozambique tilapia (Oreochromis mossambicus) in its native range, southern Africa, and provide a method for identifying hybrids with genetic markers. We genotyped the mitochondrial DNA (mtDNA) control region (385 bp) of wild and farmed O. mossambicus, wild and farmed O. niloticus and morphologic wild hybrids. These data were complemented with published sequences of parapatric and sympatric Oreochromis taxa. Phylogeographic analysis showed the presence of two O. mossambicus lineages, the southernmost representing a recent Holocene radiation. Hybridization of O. mossambicus was indicated by the presence of O. niloticus and O. mortimeri–andersonii mtDNA specimens in the Limpopo basin and of O. karongae mtDNA in specimens from Malawi. We also genotyped seven suspected hybrid individuals from the Limpopo River, and 137 wild and farmed Mozambique and Nile tilapia samples with five microsatellite markers. Factorial Component Analysis, Bayesian clustering and assignment analyses consistently delineated an O. mossambicus and an O. niloticus group, with the putative hybrids positioned in between. Different levels of hybridization were detected by the Bayesian assignment. The complex nature of hybridization and introgression between cichlid species raises major concerns for the long-term integrity of Mozambique tilapia.     

Phylogenetic relationship of Kappaphycus Doty and Eucheuma J. Agardh (Solieriaceae, Rhodophyta) in Malaysia

The genera Kappaphycus Doty and Eucheuma J. Agardh are important sources of carrageenan in Malaysia, offering lucrative revenues to the carrageenan industry, economy, and the local community. The extensive range of morphotypes and the lack of distinct morphological characteristics led to the application of molecular systematics in elucidating this taxonomic confusion. Local varieties of Kappaphycus and Eucheuma, identified using putative external morphology, were analyzed using the mitochondrial cox2–3 spacer and plastid RuBisCO spacer molecular markers. Phylogenetic analysis of these and non-local specimens indicate that Kappaphycus and Eucheuma are genetically distinct. Three main genotypes of Kappaphycus alvarezii were identified, of which two are extant in Hawaii. Morphological and color variations are not supported by molecular data, indicating that most of the local names are not genetically based. Both the cox2–3 spacer and RuBisCO spacer generated phylogenetic trees with similar topology except in variation of nodal supports. The two markers showed clear separation between Kappaphycus and Eucheuma and the existence of three Malaysian Kappaphycus cultivars. Cox2–3 spacer data is more variable and provides better resolution than the RuBisCO spacer, showing that Kappaphycus is more diversified with a larger number of genotypes, strains, and species which are unique to Southeast Asia. Kappaphycus sp. “Aring-aring” appeared to be phenotypically and genotypically different from other Kappaphycus congeners, whereas Kappaphycus striatum exhibited two different genotypes. Our data indicate that Eucheuma denticulatum is the dominant species in Malaysian waters and also suggested paraphyly in Eucheuma which will require further studies. The application of molecular taxonomy on Malaysian Kappaphycus and Eucheuma proves useful, offering valuable insights into the taxonomy and distribution of these commercially important Rhodophytes.     

152 Non‐Indigenous and Invasive Marine Algae in Hawaii

The introduction of non‐indigenous species is currently viewed as one of the largest threats to global biodiversity. Non‐indigenous marine algae (NIMA) in temperate seas around the world have caused significant losses to ecosystem structure and function. However, the introduction of invasive species in tropical marine ecosystems has not typically been viewed as a significant threat despite the number of species that have been transported to reef regions around the world for open‐reef aquaculture. The research presented here represents some of the first quantified evidence of significant negative impacts of NIMA in tropical waters. This study characterized several ecological and physiological aspects of one the most successful and potentially threatening NIMA on Hawaii's coral reefs, K. alvarezii. Results of large‐scale surveys and a number of permanently established invader removal plots suggest that K. alvarezii is having negative impacts on native species diversity. Interactions between K. alvarezii and coral abundance were examined using photoquadrats and results indicate that the invader is causing coral death as a result of overgrowth and shading. Possible mechanisms influencing invader success including responses to nutrient enrichment, grazer consumption rates and reproductive characteristics were examined. Results from a number of experiments suggest that without mitigation K. alvarezii will continue to spread. In an effort to minimize negative impacts and prevent spread several management strategies were examined including manual removal, use of chemical and temperature treatments and enhancement of native sea urchins. While some of these tools are promising control options, rapid implementation is needed to prevent further damage.     

Macroalgae Biorefinery from <Emphasis Type="Italic">Kappaphycus alvarezii:</Emphasis> Conversion Modeling and Performance Prediction for India and Philippines as Examples

Marine macroalgae are potential sustainable feedstock for biorefinery. However, this use of macroalgae is limited today mostly because macroalgae farming takes place in rural areas in medium- and low-income countries, where technologies to convert this biomass to chemicals and biofuels are not available. The goal of this work is to develop models to enable optimization of material and exergy flows in macroalgal biorefineries. We developed models for the currently widely cultivated red macroalgae Kappaphycus alvarezii being biorefined for the production of bioethanol, carrageenan, fertilizer, and biogas. Using flux balance analysis, we developed a computational model that allows the prediction of various fermentation scenarios and the identification of the most efficient conversion of K. alvarezii to bioethanol. Furthermore, we propose the potential implementation of these models in rural farms that currently cultivate Kappaphycus in Philippines and in India.     

Phylogeny and biogeography of the parrot genus Prioniturus (Aves: Psittaciformes)

The parrot genus Prioniturus occurs in the oceanic Philippines, Palawan and Wallacea, a geologically dynamic region with a complex history of land and sea. The described taxa of Prioniturus have been variously placed in different assemblages, and different numbers of species have been recognized. However, a phylogenetic framework is so far lacking. This would be the prerequisite to reconstructing dispersal and colonization patterns of Prioniturus across and within Wallacea and the Philippines. Following our robustly supported phylogenetic hypothesis based on two mitochondrial genes, we propose to treat Prioniturus mindorensis comb. nov. as well as Prioniturus montanus and Prioniturus waterstradti as separate species. In Prioniturus discurus discurus and Prioniturus discurus whiteheadi, further studies using additional data and specimens are necessary to clarify their taxonomic status. This result is congruent with other studies demonstrating that alpha diversity of the Philippine avifauna is strongly underestimated. According to our biogeographic reconstruction, Prioniturus has diversified by a complex combination of colonization of islands and subsequent divergence in allopatry among and within island groups. Dispersal between Sulawesi/Wallacea and the Philippines occurred twice and documents a rare case of faunal exchange between these two regions.     

Ultrastructural,morphological, and molecular characterization of Colaconema infestans (Colaconematales,Rhodophyta) and its host Kappaphycus alvarezii (Gigartinales,Rhodophyta) cultivated in the Brazilian tropical region

Endophytic and epiphytic infections have caused serious problems for Kappaphycus farmers, such as reduction in biomass production and decrease in the yield and quality of carrageenan. During environmental monitoring from January 2011 to December 2012, along Pitimbu Beach, Paraíba State, northeastern Brazil, drifting thalli of Kappaphycus alvarezii (Gigartinales, Rhodophyta) were detected with red spots, apparently caused by epiphytic/endophytic infections. Therefore, drifting thalli of K. alvarezii farmed along the northeastern Brazilian coast were cultured in the laboratory and submitted to molecular and morphological analyses to identify and characterize the causative agent and its effects on the cellular structure and ultrastructure of the host alga K. alvarezii that was found to be infected by the endophyte Colaconema infestans (Colaconematales) identified through morphological and rbcL molecular evidence. Infected thalli of K. alvarezii were processed and analyzed through light, transmission electron, and scanning electron microscopy. Alterations were observed in morphology and cellular organization, including structural changes of chloroplasts and decrease in floridean starch grains, along with increased cell wall thickness. Therefore, while no outbreak has been reported, the discovery of C. infestans infection in drifting thallus of K. alvarezii suggests a potential threat to its cultivation that should be monitored.     

Kappaphycus alvarezii (Gigartinales, Rhodophyta) cultivated in Brazil: is it only one species?

Kappaphycus alvarezii which is endemic to the Indo-Pacific region is the main raw material for kappa carrageenan production. A seedling that was cultivated in Japan (originally from the Philippines) was introduced in a trial, for aquaculture purpose, in 1995, in São Paulo State, southeastern region of Brazil. It was later introduced in Santa Catarina State, in Southern Brazil. In 1998, another seedling that was brought from Venezuela, also originally from the Philippines, was commercially introduced at Ilha Grande Bay and later on at Sepetiba Bay, both in Rio de Janeiro State. The aim of this study was to characterize 21 samples from different farms (Rio de Janeiro and Santa Catarina States) and verify if they are K. alvarezii or other species. Based on the intergenic spacer cox2-3 sequences, phylogenetic relationships were inferred through neighbor joining, maximum likelihood, and Bayesian analyses. The topology of the trees suggests that all samples from the different farms form a monophyletic group of K. alvarezii. Statistical analysis of the cox2-3 marker calculated with median-joining network showed 38 variable positions defining 15 haplotypes for the studied samples of Kappaphycus. The most frequent K. alvarezii haplotype grouped the samples cultivated worldwide with the Brazilian samples. These results are important for better productivity and are environmentally desirable for introduction purposes since the species introduced is known and will help focusing the research on this species. This knowledge can be of assistance to the government in setting up environmental and cultivation protocols to achieve sustainability in macroalgae aquaculture.     

Relationships among Eucheuma denticulatum,Eucheuma isiforme and Kappaphycus alvarezii (Gigartinales,Rhodophyta) based on nuclear ssu-rRNA gene sequences

The nuclear genes encoding small-subunit ribosomal RNAs (ssu-rDNAs) of the carrageenophytes Eucheuma denticulatum, E. isiforme and Kappaphycus alvarezii were amplified by the polymerase chain reaction, cloned and sequenced. The sequences range from 1767 (K. alvarezii) to 1781 (E. isiforme) nucleotides in length, and have guanine+cytosine contents between 51.2% (E. isiforme) and 51.5% (E. denticulatum). Pairwise sequence identities among these sequences ranged from 97.6% to 98.5%, levels comparable to some intergeneric identities within Gracilariales. In phylogenetic analyses, the two Eucheuma ssu-rDNAs group stably together vis-a-vis the ssu-rDNA of K. alvarezii, and these three ssu-rDNAs form a monophyletic group within a larger grouping of other carrageenophytes. The results demonstrate quantitatively that analysis of nuclear-encoded ssu-rDNA sequences is likely to be useful in resolving taxonomic, phylogenetic and biogeographic questions among tribe Eucheumatoideae Doty.     

Optimization of culture conditions for tissue culture production of young plantlets of carrageenophyte <Emphasis Type="Italic">Kappaphycus</Emphasis>

To improve the production of Kappaphycus plantlets in tissue culture, optimum media concentrations of an Ascophyllum nodosum extract (Acadian Marine Plant Extract Powder, AMPEP), plant growth regulators (PGR), pH–temperature combinations, and explant density were determined. Kappaphycus alvarezii var. tambalang purple (PUR), kapilaran brown (KAP), vanguard brown (VAN), adik-adik (AA), tungawan green (TGR), and K. striatum var. sacol green (GS) were used as explants. Based on the shortest period for shoot emergence and the economical use of AMPEP, the optimum enriched media was 3.0 mg L⁻¹ AMPEP and 0.1 mg L⁻¹ AMPEP + PGR 1 mg L⁻¹ each phenylacetic acid (PAA) and zeatin for PUR, 1.0 mg L⁻¹ AMPEP + PGR for KAP and GS, 0.1 mg L⁻¹ AMPEP + PGR for VAN, and 3.0 mg L⁻¹ AMPEP and 0.001 mg L⁻¹ AMPEP + PGR for AA and TGR. Results showed that the addition of PGR to low concentrations of AMPEP hastened shoot formation. pH–temperature combinations for the most rapid shoot formation were determined for the brown (KAP) and purple (PUR) color morphotypes of K. alvarezii var. tambalang and the green morphotype of K. striatum var. sacol (GS) cultured in 1.0 mg L⁻¹ AMPEP + PGR. The brown morphotype produced the most number of shoots at pH 7.7 at 20°C after as little as 20 days. Purple K. alvarezii showed an increased shoot formation at pH 6.7 at 25°C and the green K. striatum morphotype at pH 8.7 at 25°C. The optimum number of explants added to the culture media was also determined for tungawan green (TGR), brown (KAP), and tambalang purple (PUR) varieties of K. alvarezii in 1.0 mg L⁻¹ AMPEP + PGR. The number of explants and the volume of the culture media combination were also tested. The highest average number of shoots formed occurred in two explants:1 mL culture media (2:1) for KAP and PUR (35.00% and 16.67%, respectively) and 1 explant: 2 mL culture media for the TGR (100.00%) with a range of 0.5–3.0 mm shoot length after 40 days in culture. The earliest shoot formation was observed after 21 days for the brown and 9 days for both the green and purple color morphotypes of Kappaphycus, in all densities investigated. This indicated that within the range tested, the density of explants did not have a significant effect on the rate of shoot formation but did influence the average number generated from the culture. The rate of production of new and improved Kappaphycus explants for a commercial nursery stock was improved through the use of AMPEP with optimized culture media pH, temperature, and density conditions.     

Occurrence of Polysiphonia Epiphytes in Kappaphycus Farms at Calaguas Is., Camarines Norte, Phillippines

This paper describes the occurrence of an epiphyte infestation of Kappaphycus farms in Calaguas Is. Camarines Norte, Philippines. In particular, percentage cover of ‘goose bump’-Polysiphonia and ‘ice-ice’ disease, and some environmental parameters that influence the thallus condition of Kappaphycus alvarezii in Calaguas Is. were assessed during 3 separate visits and are discussed.Commercial cultivation of Kappaphycus at Calaguas Is. began in the early 1990s. After five years of farming, the stock was destroyed by a strong typhoon. The area was re-planted the following year and production increased annually and reached its peak in 1998–1999. However, the following year, the first occurrence of a Polysiphonia epiphyte infestation occurred concurrently with an ‘ice-ice’ disease. Consequently, annual production and the number of seaweed planters declined rapidly, and this situation persists to the present time. This paper highlights the etiological factors and their consequences.Results show that farm-site selection is critical for the success of Kappaphycus production. Characteristics of water movement and light intensity in farming areas contributed to the occurrence and detrimental effect of the phenomenon described as ‘goose bumps’: a morphological distortion of the host seaweed due to the presence of a Polysiphonia sp. epiphyte. A strong inverse correlation was observed between the occurrence of Polysiphonia and water movement: areas with low water motion registered a higher % cover (65%) of Polysiphonia than those in more exposed areas (17%). Although ‘goose bump’-Polysiphonia infestation and ‘ice-ice’ disease pose a tremendous problem to the seaweed farmers, the results of this limited assessment provide a useful baseline for future work.     

Self-incompatibility alleles in Polish wild pear (Pyrus pyraster (L.) Burgsd.): a preliminary analysis

Wild pear (Pyrus pyraster, syn.P. communis var.pyraster) is thought to be one of the species that gave rise to all other members of the genusPyrus, although intraspecific hybridizations with cultivated varieties could cause the disappearance of original species characteristics. S-RNase alleles from 7 different wild pear individuals, collected from various regions of Poland, were cloned on the basis of the PCR method and nucleotide sequence analyses. The hypervariable (HV) region is responsible for allele-specific S-RNase activity in the self-incompatibility mechanism. The high level of polymorphism of its sequences may constitute a source of valuable phylogenetic information. From all individuals, 14 sequences were obtained successfully, and 9 of them were novel alleles. Phylogenetic analysis of these alleles was based on the amino acid sequence interpretation of coding regions and intron nucleotide sequences. The research conducted on a limited pool of availableP. pyraster alleles gives only an initial insight into possible S-RNase allele polymorphisms in wild populations. At this stage, the results do not confirm a strong influence of cultivated pear species on the wild pear.     

Cultivation and utilisation of red seaweeds in the Western Indian Ocean (WIO) Region

Seaweed farming in the Western Indian Ocean (WIO) Region is carried out in a number of countries, most of them farming Eucheuma denticulatum, Kappaphycus alvarezii and Kappaphycus striatum. These species are farmed mostly in Tanzania with limited production in Madagascar, Mozambique and Kenya; current production (2012) stands at 15,966 t (dry weight) year^?1 of Eucheuma and Kappaphycus, valued at US$ 4.2 million with 95 % of this tonnage coming from Tanzania. Other countries in the region have limited or no seaweed production owing to problems of epiphytes, ice ice and markets. The problem of epiphytes coupled with ice ice that WIO countries are facing causes die-off of Kappaphycus which is the preferred species in foreign markets for its thicker gel, kappa carrageenan (vs. the weaker iota carrageenan from Eucheuma). New efforts are put to curb these problems including moving seaweed farms to deeper waters and cultivation trials of other carrageenophytes as well as agar-producing species, agarophytes. Research work has been initiated to evaluate Gracilaria and Hypnea farming and processing in Tanzania, the Republic of Mauritius and Mayotte. Gracilaria farming is at experimental stages as a biofilter of fishpond effluents and as potential species for the production of agar with growth rates of 1.5–1.9 % day^?1. Hypnea farming is only being initiated in Mauritius and Mayotte at present. Other innovations including value addition by making various seaweed products and encouraging the consumption of seaweed as food at least in Tanzania and Mauritius are increasing further the importance of the seaweed farming and processing industry in the WIO Region.