Orophea sichaikhanii (Annonaceae), a new species from southern Thailand, with a key to the species of Orophea in Thailand and notes on some species

Background and aims – Recent botanical expeditions in Ranong Province, southern Thailand yielded unidentifiable collections of Orophea subgenus Sphaerocarpon (Annonaceae). To elucidate the taxonomic status of these collections, detailed morphological examinations and comparisons with morphologically similar species are made.Material and methods – This study followed standard practices of herbarium taxonomy. Specimens of Orophea spp. in BKF, CMUB, L, and QBG herbaria were studied. Digitised type specimens deposited in BM, E, G, K, and L herbaria were accessed. A stereo microscope was used for morphological observations and measurements. Key results – A new species Orophea sichaikhanii is described and illustrated. The Peninsular Malaysian O. hastata and O. kingiana are the species most similar to the new species. Orophea sichaikhanii is different from O. hastata in several traits: indumentum on ovaries and young twigs; length of pedicels, inner petals, and inner petal claw; and inner petal colour and tip. The new species differs from O. kingiana by having dissimilar colour and tip of inner petals; lower number of stamens and carpels per flower; and glabrous ovaries. Additionally, a key to the species of Orophea in Thailand and notes on certain species are provided.

Effects of the Relatedness of Neighbours on Floral Colour

The reproductive success of plants depends both on their phenotype and the local neighbourhood in which they grow. Animal-pollinated plants may benefit from increased visitation when surrounded by attractive conspecific individuals, via a “magnet effect.” Group attractiveness is thus potentially a public good that can be exploited by individuals, with selfish exploitation predicted to depend on genetic relatedness within the group. Petal colour is a potentially costly trait involved in floral signalling and advertising to pollinators. Here, we assessed whether petal colour was plastically sensitive to the relatedness of neighbours in the annual herb Moricandia moricandioides, which produces purple petals through anthocyanin pigment accumulation. We also tested whether petal colour intensity was related to nectar volume and sugar content in a context-dependent manner. Although both petal colour and petal anthocyanin concentration did not significantly vary with the neighbourhood configuration, plants growing with kin made a significantly higher investment in petal anthocyanin pigments as a result of the greater number and larger size of their flowers. Moreover the genetic relatedness of neighbours significantly modified the relationship between floral signalling and reward quantity: while focal plants growing with non-kin showed a positive relationship between petal colour and nectar production, plants growing with kin showed a positive relationship between number of flowers and nectar volume, and sugar content. The observed plastic response to group relatedness might have important effects on pollinator behaviour and visitation, with direct and indirect effects on plant reproductive success and mating patterns, at least in those plant species with patchy and genetically structured populations.

Integrated metabolic profiling and transcriptome analysis of pigment accumulation in Lonicera japonica flower petals during colour-transition

Background Plants have remarkable diversity in petal colour through the biosynthesis and accumulation of various pigments. To better understand the mechanisms regulating petal pigmentation in Lonicera japonica, we used multiple approaches to investigate the changes in carotenoids, anthocyanins, endogenous hormones and gene expression dynamics during petal colour transitions, i.e., green bud petals (GB_Pe), white flower petals (WF_Pe) and yellow flower petals (YF_Pe). Results Metabolome analysis showed that YF_Pe contained a much higher content of carotenoids than GB_Pe and WF_Pe, with α-carotene, zeaxanthin, violaxanthin and γ-carotene identified as the major carotenoid compounds in YF_Pe. Comparative transcriptome analysis revealed that the key differentially expressed genes (DEGs) involved in carotenoid biosynthesis, such as phytoene synthase, phytoene desaturase and ζ-carotene desaturase, were significantly upregulated in YF_Pe. The results indicated that upregulated carotenoid concentrations and carotenoid biosynthesis-related genes predominantly promote colour transition. Meanwhile, two anthocyanins (pelargonidin and cyanidin) were significantly increased in YF_Pe, and the expression level of an anthocyanidin synthase gene was significantly upregulated, suggesting that anthocyanins may contribute to vivid yellow colour in YF_Pe. Furthermore, analyses of changes in indoleacetic acid, zeatin riboside, gibberellic acid, brassinosteroid (BR), methyl jasmonate and abscisic acid (ABA) levels indicated that colour transitions are regulated by endogenous hormones. The DEGs involved in the auxin, cytokinin, gibberellin, BR, jasmonic acid and ABA signalling pathways were enriched and associated with petal colour transitions. Conclusion Our results provide global insight into the pigment accumulation and the regulatory mechanisms underlying petal colour transitions during the flower development process in L. japonica.

Evaluation of Dolichos Genotypes (Dolichos lab lab L.) under Northern Telangana Zone

A field trial was conducted at Horticultural Research Station, Adilabad of Northern Telangana Zone in Telangana State, India for two consecutive years of 2018 and 2019 with forty five genotypes of dolichos bean. The study was initiated to study the vegetative, floral characters and yield performance of different genotypes. The experiment was laid by adopting Randomized block design with two replications each in 2018 and 2019. Significant variations were noticed in the vegetative, floral characteristics; yield attributes and yields among the different genotypes. Stem pigmentation varied from meager or no pigmentation in 33 genotypes to almost solid in IC-426968 and IC-427428. The leaf colour was green and dark green in 12 and 33 genotypes respectively. The leaf shape was round (IC-426968), lanceolate, ovate lanceolate and ovate in 2, 10 and 32 genotypes. The standard petal colour and keel petal colour varied among the genotypes. It was cream, pink, purple and white. Maximum pod length was reported by IC-427436 and IC-427462 (16.15 cm), mean pod width by PSRJ-12953 (6.36 cm), mean pod weight by IC-427436 (11.05 g) and number of seeds per pod (6.35) by genotype Sambram. The genotype IC-427436 recorded significantly higher pod yield per plant (2713 g) and pod yield per hectare (13563 kg) over rest of the genotypes and it was followed by the genotypes IC-427462 and RND-1.

Integrated metabolic profiling and transcriptome analysis of pigment accumulation in Lonicera japonica flower petals during colour-transition

Background: Plants have remarkable diversity in petal colour through the biosynthesis and accumulation of various pigments. To better understand the mechanisms regulating petal pigmentation in Lonicera japonica, we used multiple approaches to investigate the changes in carotenoids, anthocyanins, endogenous hormones and gene expression dynamics during petal colour transitions, i.e., green bud petals (GB_Pe), white flower petals (WF_Pe) and yellow flower petals (YF_Pe). Results: Metabolome analysis showed that YF_Pe contained a much higher content of carotenoids than GB_Pe and WF_Pe, with α-carotene, zeaxanthin, violaxanthin and γ-carotene identified as the major carotenoid compounds in YF_Pe. Comparative transcriptome analysis revealed that the key differentially expressed genes (DEGs) involved in carotenoid biosynthesis, such as phytoene synthase, phytoene desaturase and ζ-carotene desaturase, were significantly upregulated in YF_Pe. The results indicated that upregulated carotenoid concentrations and carotenoid biosynthesis-related genes predominantly promote colour transition. Meanwhile, two anthocyanins (pelargonidin and cyanidin) were significantly increased in YF_Pe, and the expression level of an anthocyanidin synthase gene was significantly upregulated, suggesting that anthocyanins may contribute to vivid yellow colour in YF_Pe. Furthermore, analyses of changes in indoleacetic acid, zeatin riboside, gibberellin (GA), brassinosteroid (BR), methyl jasmonate and abscisic acid (ABA) levels indicated that colour transitions are regulated by endogenous hormones. The DEGs involved in the auxin, cytokinin, GA, BR, jasmonic acid and ABA signalling pathways were enriched and associated with petal colour transitions.Conclusion: Our results provide global insight into the pigment accumulation and the regulatory mechanisms underlying petal colour transitions during the flower development process in L. japonica.

Acanthostachys calcicola (Bromeliaceae, Bromelioideae), a new species from a limestone outcrop in Tocantins State, Brazil

A new species of bromeliad, Acanthostachys calcicola, a third taxon for the genus, is here described. A. calcicola was discovered during field work in the limestone outcrops of south-eastern Tocantins, central Brazil. It is most similar to A. strobilacea, but differs from it in petal colour and length, and exserted stamens and pistil. A conservation assessment classifies A. calcicola as endangered (EN) with extinction.