Begonia xuansonensis, a new orange-flowered species of Begoniaceae from northern Vietnam

Begonia xuansonensis, a new species from northern Vietnam, is described and illustrated. The new species is characterized by reddish-orange to orange tepals, which is a rare type of flower coloration in Asian species of the genus. Begonia xuansonensis is most similar to B. lowiana, but differs from the latter by stipules 4–6 × 1.5–2 mm, orange tepals and ovary, and abaxially densely red setose inner tepals of staminate and pistillate flowers. The new species also shows similarity with B. cathayana, differing in stipules 4–6 mm long, uniformly dark green adaxial side of leaf blade, abaxially densely red setose inner tepals of a staminate flower and three styles in a pistillate flower. Begonia xuansonensis is tentatively assigned to B. sect. Platycentrum on the basis of actinomorphic androecium, apically rounded anthers and fruit with three unequal wings. Morphological description and detailed photographs of the new species are provided, accompanied by information on its ecology, provisional conservation status, and a taxonomic comparison with similar species.

Two new species of Begonia (sect. Platycentrum, Begoniaceae) from the Central Highlands of Vietnam: B. villosula and B. lophura

Two new species of Begonia L., namely Begonia villosula T.S.Hoang & C.W.Lin and B. lophura T.S.Hoang & C.W.Lin, from the Central Highlands of Vietnam, are described and illustrated. They are assigned to Begonia sect. Platycentrum based on several characters including axillary inflorescence, 4-tepaled staminate flower and 5-tepaled pistillate flower with bilocular ovary, each with two placentae. Begonia villosula resembles B. thomsonii, but it is different in its leaf margins crenate to crenulate (vs. irregularly serrulate), stamens 80–120 (vs. 35–70), pistillate flower 4-tepaled (vs. 5-tepaled) and ovary hirsute (vs. villous). Begonia lophura is somewhat similar to B. pavonina, but it is different in having widely ovate (vs. ovate) and abaxially red hirsute (vs. glabrous) leaves, bracts persistent (vs. caducous), tepals hirsute (vs. glabrous) in both of staminate and pistillate flowers, capsule scabrous (vs. glabrous) and abaxial wing strongly swollen (vs. thin, not swollen). The conservation status of the two new species are assessed as Vulnerable according to the IUCN Red List criteria.

Seven new species and seven new records of Begonia L. (Begoniaceae) in the flora of Laos

New species of Begonia L. in the flora of Laos presented in this paper were mainly found in the course of botanical surveys made in Hin Nam No National Protected Area, Nam Phouy National Protected Area, Khammouane Karst Forest, and Phou Khao Khouay National Protected Area.Additionally, herbaria presently available in Laos (HNL, FOF, NUoL, FRC), living plants, and alcohol preserved material at Pha Tad Ke Botanical Garden and the data accessible online at BM, E, K, LE, NY, P, and PE Herbaria were critically studied. The study conducted during 2012–2019 reveals seven new species for science and seven species newly recorded for the flora of Lao PDR. Species described as new for science are: B. glabritepala (found in Khammouane Province; it is most close to B. pierrei but differs in glabrous outer tepals of staminate flowers, pistillate flowers, capsules, petioles, peduncles and pedicles), B. heterocantha (found in Sainyabuli Province; most close to B. depingiana but differs in reddish purple, glandular pubescent abaxial leaf surface, glandular pubescent pedicel, and outer tepals of pistillate flowers sparsely white glandular pubescent), B. lanxangensis (found in Vientiane Province; most close to B. paleacea but differs in elongate tubers, ovate-lanceolate, obscurely asymmetrical to symmetrical leaves, and glabrous pedicels), B. parviglandulosa (found in Vientiane Province; most close to B. martabanica but differs in smaller habit, reniform-cordate leaves and glandular indumentum on peduncle, pedicle and capsules), B. pseudobrandisiana (found in Khammouane Province; most close to B. brandisiana but differs in pistillate flowers with five elliptic-oblanceolate tepals), B. tripartifolia (found in Khammouane Province; most close to B. tricuspidata but differs in leaves palmate triangular-ovate, with deeply lobed lacerate margin, pistillate flower of five tepals, and ovary with unequal wing), and B. viriditenebris (found in Khammouane Province; most close to B. sinuata but differs in single leaf, indumentum of bristle hairs and reddish or bronzy green adaxial leaf surface, and three styles). The following species discovered and recorded for the flora of Laos at first are: B. hatacoa (known in Nepal, Bhutan, NE India, Myanmar, Thailand, and Vietnam), B. hemsleyana (China, Vietnam), B. labordei (NE India, Myanmar, S China, Vietnam), B. longifolia (tropical zone from NE India to Indonesia), B. minuscula (Vietnam), B. parvula (S China), and B. subperfoliata (Myanmar, Thailand, S Vietnam). Descriptions and line drawings are provided for all newly described species. Photographic illustrations, data on phenology, habitat, and notes on morphological variations and relations are given for all studied species.

Sexual and ontogenetic structures of gynodioecious Geranium pseudosibiricum J. Mayer (Geraniaceae) in Altai Mountains

Geranium pseudosibiricum J. Mayer. is a gynodioecious North and Central Asian species. The study was conducted in a grass meadow on the edge of larch forest in the Altai Republic. The aim was to study the sexual and ontogenetic structures of the coenopopulation of G. pseudosibiricum. The generative individual consists of shoots of only one sexual form: hermaphrodite with bisexual flowers and female with pistillate flowers. There are significant differences in the length of corolla: the length of bisexual flowers is 12.2 ± 0.29 mm, pistillate flowers 6.7 ± 0.19 mm. The bisexual flower has well-developed stamens and anthers; the pistillate flower has stamens with underdeveloped anthers. There are no significant differences between hermaphrodite and female individuals in the number of generative shoots and the number of flowers per individual. The ontogenetic structure of the coenopopulation of G. pseudosibiricum is dominated by pregenerative individuals − 53%. Good seed germination contributes to maintenance of sexual structure of the coenopopulation. The female frequency is 55% of the total number of generative plants. The detected morphological differences between bisexual and pistillate flowers and the high female frequency may indicate a high degree of sexual differentiation of G. pseudosibiricum.

Flower morphogenesis and gametophyte fertility attest to the rare condition of gynomonoecy in Parietaria debilis (Urticaceae)

Parietaria debilis G. Forst. is gynomonoecious, which is a rare condition in the Urticaceae family and among angiosperms. Apetalous flowers of two different morph types (monoclinous, pistillate) occur in the same inflorescence and are reduced in size and in the number of whorls and of organs per whorl. The objective of this study was to compare the morphogenesis of monoclinous and pistillate flowers to determine whether the monoclinous flowers produce fertile gametophytes, and elucidate the pathways leading to the absence of stamens and to the changes in number of whorls and organs per whorl. Flower buds and flowers (non-fertilized, fertilized) were processed for surface and anatomical studies. Pollen ultrastructure and viability were determined. Inflorescences with fertilized flowers were checked for the presence and location of fruits/viable seeds. The monoclinous flower has four sepals, four stamens, and a uniovulate pseudomonomerous gynoecium. In the pistillate flower, the stamens are absent or, rarely, aborted. No petals are formed. The gynoecium is pseudomonomerous, originated as a central primordium that differentiates into two carpels, but only one develops and houses an ovule. Monoclinous and pistillate flowers produce viable seeds. Thus, our data confirmed that this species is indeed gynomonoecious.

A Revised Sectional Classification of Plukenetia L. (Euphorbiaceae, Acalyphoideae) with Four New Species from South America

Abstract—We present a phylogenetic classification for Plukenetia (Euphorbiaceae, Acalyphoideae) based on morphology and molecular phylogenetic studies using nuclear (ETS, ITS, KEA1 introns 11 and 17, TEB exon 17) and plastid (matK, ndhF, psbA-trnH) DNA data. Plukenetia comprises 25 species divided into six sections, with three new sections and four new species described here. The circumscription of Plukenetia is unaltered from recent treatments and we continue to recognize Romanoa as distinct. The sections of Plukenetia correspond with the subclade system proposed by Cardinal-McTeague and Gillespie (2016): P1 = P. sect. Fragariopsis comb. et stat. nov.; P2 = P. sect. Penninerviae sect. nov.; P3 = P. sect. Plukenetia; P4 = P. sect. Angostylidium; and P5 = P. sect. Hedraiostylus + P. sect. Madagascarienses sect. nov. The sections are distinguished by a combination of leaf venation, staminate flower morphology, pistillate flower number, style morphology, fruit type, and seed size. Additionally, we describe three new species from South America belonging to sect. Penninerviae: Plukenetia brevistyla and Plukenetia megastyla from the Amazon basin and Plukenetia chocoensis from the Chocó Biogeographic Region of Colombia. The new Amazonian species are morphologically similar to P. brachybotrya but distinguished by their style shape and size. The new Colombian species is morphologically similar to P. penninervia but distinguished by its elongate basilaminar extrafloral nectaries, presence of abaxial laminar extrafloral nectaries, and longer inflorescences. We also describe a new species from sect. Plukenetia, Plukenetia sylvestris, which is found in central and southern Peru. This species is suggested to be the wild progenitor of the cultivated P. carolis-vegae, differing by its smaller seeds/fruits and fewer stamens. Molecular data, including a new ETS phylogeny sampling P. brevistyla, support our new taxa as distinct. Keys to the sections and species of Plukenetia are provided and we designate 12 new lectotypes for Plukenetia and Romanoa.

Assessment of Yield and Quality Characters in Pumpkin from North East India

Twenty five diverse pumpkin germplasm from North East India were assesed for correlation and path coefficient analysis. Correlation revealed that, characters like number of fruit per plant had significant positive correlation with fruit yield per plant both at genotypic and phenotypic level. Path Coefficient Analysis revealed that, days to first pistillate flower anthesis (1.185) and number of fruits per plant (0.681) had maximum positive direct effect on fruit yield per plant.These are the real independent characters and have maximum contribution towards fruit yield per plant at genotypic level. Whereas at phenotypic level, fruit yield per plant was imposed by number of fruits per plant (0.664) only. From the overall result, the traits like days to first pistillate flower anthesis and numbers of fruits per plant can be utilize for breeding programme to increase fruit yield per plant in pumpkin.

Two new species, Begonia dinhdui and B. bacmeensis (Begoniaceae), from Vietnam

Two new species, Begonia dinhdui and B. bacmeensis are described from Vietnam. Begonia dinhdui is somewhat similar to B. austrovietnamica C.-I Peng, C.W. Lin, D.D. Nguyen & N.D. Truong, a limestone tuberous species also occurring in southern Vietnam. Both species have a periodically dormant habit and silvery variegated lamina, however, the new species differs in having a rhizomatous (vs. tuberous) rootstock, cymose (vs. racemose) inflorescence and 4-tepaled (vs. 6-tepaled) pistillate flower. Another new species, Begonia bacmeensis most closely resembles B. psilophylla Irmsch. in its stout rhizomatous rootstock, 4-tepaled staminate flower and 5-tepaled pistillate flower, but differs from the latter by having a strongly asymmetrical (vs. subsymmetric), lanceolate to oval-lanceolate (vs. ovate) lamina, tepals of staminate and pistillate flower pale green (vs. pink), ovary lateral wings surface verrucose or echinate (vs. nearly flat). Begonia dinhdui is currently known only from a single locality in Lâm Đồng Province while B. bacmeensis is rather common in Hà Giang Province.