New records of mass seeding Cephalostachyum latifolium Munro (Poaceae) along the mid-elevation broadleaved forest of Sarpang district, Bhutan

Mass seeding of Cephalostachyum latifolium under Sarpang district, Bhutan. However, Bhutan till dates has recorded only two Cephalostachyum species (C.Meanwhile, Meanwhile, recent record of gregarious and mass seeding of Cephalostachyum latifolium bamboo species from the mid-elevation broadleaved forest of Sarpang district in Bhutan has added another new records to bamboo science in 2017.C. In Bhutan, gregarious flowering of C. Therefore, gregarious and mass seeding has immense social, economic and ecological implications to the communities.

Gregarious flowering in Dendrocalamus strictus (Roxb.) Nees in Mussoorie Hills, Uttarakhand, India

Dendrocalamus strictus (Roxb.) Nees has started flowering and synchronous flowering can be observed in the hillslopes and roadside of Mussoorie and vicinity areas. The synchronous flowering of D. strictus was observed in few locations along hillslopes of Mussoorie – Dehradun roadway. The GPS locations of the site are 30024’55’ N and 7804’41’E, 30024’52” N and 7804’43” E and 30024’49” and 7804’43” E at an elevation of around 1130 msl. The bamboo clumps were overladen with flowers showing synchronous flowering.

A population genetics study of three native Mexican woody bamboo species of Guadua (Poaceae: Bambusoideae: Bambuseae: Guaduinae) using nuclear microsatellite markers

Background: Sporadic flowering contributes significantly to genetic diversity and connectivity among populations. Woody bamboos present sporadic or gregarious flowering patterns with long flowering cycles. In this study, we analyze the genetic diversity of three Guadua species distributed along the Gulf of Mexico slope that have different patterns of flowering. Questions: (1) Are the three Guadua species genetically differentiated? (2) Does the vulnerable species G. inermis have low levels of genetic diversity? (3) What is the relative contribution of geographic and environmental factors to the genetic structure of G. inermis? Species studied: Guadua inermis, G. amplexifolia and G. tuxtlensis Study site and dates: During 2014 and 2015, we collected samples of G. inermis in Puebla and southeastern Mexico, G. amplexifolia in Veracruz and Oaxaca, and G. tuxtlensis in southern Veracruz. Methods: We successfully amplified five of nine SSR markers, and genotyped a total of 155 samples. Results: The three Guadua species were genetically differentiated. For G. inermis, we found high levels of population genetic diversity, which are relatively higher than those of other monocot species. Genetic differentiation was high and three groups were detected: north, central and south. We found a significant association between genetic distances and the maximum temperature of the warmest month, but not with geographic distance. Conclusions: Our study is the first to analyze levels of genetic diversity in Mexican bamboos and confirms their taxonomic identity. G. inermis has a strong genetic structure, even when populations are geographically close.

Field Study of Gregarious Flowering and Use of ENM in Conservation Strategies for Gigantochloa andamanica (Kurz) Kurz in Andaman Islands (India)

Gregarious flowering in bamboo species is a periodic event which affects the habitat’s ecology, since the whole population die within same time frame. The phenomenon sets effects on the social economy too as bamboo is one of the most important natural resources people depends on. In this paper gregarious flowering and mass seeding in Gigantochloa andamanica (Kurz) Kurz, an economically important bamboo species of Andaman Islands have been reported with effective conservation strategies to balance the population in natural habitat. This also includes the description, illustration, photo plates of the species for the easy identification, the ENM map based on the GPS data collected for the distribution area and data relevant to traditional and economic uses of the species. This study more importantly shows the application of ENM for the identification of suitable sites for field reintroduction of the seedlings in natural habitats aimed at their better growth and survival.

Sporadic flowering of Bambusa tulda in Mizoram: A preliminary report

Bambusa tulda Roxb. is a semi-deciduous caespitose bamboo endemic to Indo-Burma. It is known as ‘rawṭhing’ in Mizoram, India, and its mass gregarious flowering is called ṭhingtâm. ‘Ṭhingtâm’ has a cycle of about 45-50 years. The first ṭhingtâm, recorded in the region was in 1880, which was preceded by mautâm (gregarious flowering of Melocanna baccifera) in 1862; i.e., the ṭhingtâm phenomenon occurred ~20 years after the Mautâm. The last ṭhingtâm was recorded in 1981. However, there has been a localised ṭhingtâm at Zawlnuam, a village at the northwestern Mizoram. The first flowering was recorded in 2015. This unusual phenomenon needs to be investigated.

Overexpression of human peroxisomal enoyl-CoA delta isomerase2 HsPECI2, an ortholog of bamboo expressed during gregarious flowering alters salinity stress responses and polar lipid content in tobacco

Peroxisomal enoyl-CoA delta isomerase2 (PECI2) is one of the key enzymes that has critical role in lipid metabolism and plant development during salt stress. Seven out of ten tobacco plants overexpressing human PECI2 (HsPECI2) with PTS1-sequence showed hypersensitivity to salt. Under salt-stress, T2 transformed plants (HsPECI2) displayed reduced primary root, delayed shoot-growth, and visibly smaller rosette leaves turning pale yellow as compared to the pKYLX71 vector control plant. Also, we found altered reactive oxygen species (ROS) levels and reduced catalase activity in 100 mM sodium chloride (NaCl) treated HsPECI2 transformed plant compared with the pKYLX71 counterpart. ESI-MS/MS data showed that the polar lipids were differentially modulated upon salt treatment in HsPECI2 transformed and pKYLX71 plants as compared with the respective untreated counterpart. Notably, the levels of monogalactosyldiacylglycerol and phosphatidic acid varied significantly, whereas phosphatidylcholine, phosphatidylserine and digalactosyldiacylglycerol contents were moderately upregulated. In parallel, abscisic acid (ABA) responsiveness assay confirmed insensitivity of HsPECI2 transformed plant towards ABA. Overall our data proclaim that HsPECI2 play multifunctional role in normal development and response to salinity stress apart from its primary role in β-oxidation.

Bamboo, fire and flood: regeneration of Bambusa arnhemica (Bambuseae: Poaceae) after mass-flowering and die-off at contrasting sites in monsoonal northern Australia

Bambusa arnhemica F.Muell., a long-lived, gregarious-flowering and semelparous bamboo endemic to north-western Australia, occurs in remarkably disparate but somewhat fire-sheltered flood-prone riparian forest and rocky hillside vine-thickets, but not in adjacent fire-prone savannas. We investigated the response of B. arnhemica seedlings to fire and flood at two contrasting sites over 2.5 years following a mass-flowering and die-off event. Seedlings grew vigorously notwithstanding either prolonged inundation or total loss of above-ground parts to fire within their first year. However, there was no evidence that such disturbance promoted regeneration, and several veins of evidence suggest that B. arnhemica is fire-retardant and refugial rather than fire-promoting. We suggest that creation of canopy gaps by parental death is a more parsimonious and generalisable hypothesis for the evolution of gregarious semelparity in bamboos than the recently advanced bamboo fire-cycle hypothesis. However, both hypotheses are potentially group selectionist, and resolution of dispersal distances and/or the spatial genetics of relatedness are required to resolve the problem.