The island rule and its application to multiple plant traits

<p>The Island Rule refers to a continuum of body size changes where large mainland species evolve to become smaller and small species evolve to become larger on islands. Previous work focuses almost solely on animals, with virtually no previous tests of its predictions on plants. I tested for (1) reduced floral size diversity on islands, a logical corollary of the island rule and (2) evidence of the Island Rule in plant stature, leaf size and petiole length. Endemic island plants originated from small islands surrounding New Zealand; Antipodes, Auckland, Bounty, Campbell, Chatham, Kermadec, Lord Howe, Macquarie, Norfolk, Snares, Stewart and the Three Kings. I compared the morphology of 65 island endemics and their closest ‘mainland’ relative. Species pairs were identified. Differences between archipelagos located at various latitudes were also assessed. Floral sizes were reduced on islands relative to the ‘mainland’, consistent with predictions of the Island Rule. Plant stature, leaf size and petiole length conformed to the Island Rule, with smaller plants increasing in size, and larger plants decreasing in size. Results indicate that the conceptual umbrella of the Island Rule can be expanded to plants, accelerating understanding of how plant traits evolve on isolated islands.</p>

The island rule and its application to multiple plant traits

<p>The Island Rule refers to a continuum of body size changes where large mainland species evolve to become smaller and small species evolve to become larger on islands. Previous work focuses almost solely on animals, with virtually no previous tests of its predictions on plants. I tested for (1) reduced floral size diversity on islands, a logical corollary of the island rule and (2) evidence of the Island Rule in plant stature, leaf size and petiole length. Endemic island plants originated from small islands surrounding New Zealand; Antipodes, Auckland, Bounty, Campbell, Chatham, Kermadec, Lord Howe, Macquarie, Norfolk, Snares, Stewart and the Three Kings. I compared the morphology of 65 island endemics and their closest ‘mainland’ relative. Species pairs were identified. Differences between archipelagos located at various latitudes were also assessed. Floral sizes were reduced on islands relative to the ‘mainland’, consistent with predictions of the Island Rule. Plant stature, leaf size and petiole length conformed to the Island Rule, with smaller plants increasing in size, and larger plants decreasing in size. Results indicate that the conceptual umbrella of the Island Rule can be expanded to plants, accelerating understanding of how plant traits evolve on isolated islands.</p>

Cut foliage: potentiality of native Argentine ferns as new ornamental crops

The cut foliage constitutes an important part of the floricultural production since it represents a fundamental element in flower arrangements, and ferns are the complementary elements most used by florists. In Argentina, there is native material that has not been yet domesticated and could have suitable characteristics for foliage use. The objective of the work was to determine the potential use of 15 native ferns as cut foliage through quality parameters and vase life, generating a scoring system that allows a classification list. Morphological descriptors such as petiole length, length and width of the blade, planes in which the fronds are arranged, brightness, consistency, abundance of spores and presence of pests were taken into account. Also, the production of fronds of six selected species with good scores was recorded. The results showed that it is feasible to consider the commercial production of Pityrogramma calomelanos, Niphidium crassifolium, Campyloneurum nitidum, Blechnum austrobrasilianum and Pteris denticulata by the quantity of fronds obtained and their quality, represented by their size. Campyloneurum nitidum excelled for its vase life of more than 26 days and frond production of 273.61 fronds m-2 at second year cultivation. Pteris denticulata produces 179.44 fronds m-2 but vase life was only 7 days.

Two new species and one new record species of genus Arrenurus Dugès, 1834 (Acari, Hydrachnidia, Arrenuridae) from China

Three species of the genus Arrenurus Dugès, 1834 are described in detail from China, of which Arrenurus (Arrenurus) ancoralis Zheng & Guo sp. nov. and Arrenurus (Arrenurus) unguiculus Zheng & Guo sp. nov. are new to science, and Arrenurus (Truncaturus) isikliensis Boyaci & Özkan, 2004 is recorded for the first time for the Chinese fauna. Arrenurus (A.) ancoralis can be distinguished by D3 on big humps and each with a small protrusion bearing D3 gland; the petiole is well-developed, the middle part contracted, slightly enlarged posteriorly; the ligulate process extending beyond the posterior margin of the petiole and triangle-shaped. Arrenurus (A.) unguiculus can be distinguished by the ligulate process extending beyond the posterior margin for half of petiole length, and nail-shaped. Arrenurus (A.) isikliensis is recorded for the Chinese fauna for the first time. Detailed descriptions and illustrations of the new and the newly recorded species are given in this paper.

Dryopteris wulingshanensis (Dryopteridaceae), a new species from Hunan, China

Dryopteris wulingshanensis, a new species growing on limestone in the Wulingshan Mountains, Hunan, China, is described and illustrated. This species is most similar to D. jishouensis and D. gymnophylla on general morphological traits, such as the form of scales, rhizome and sori, but differs by the number of vascular bundles at the base of the petiole, length to width ratio of lamina, stalk length of basal pinnae, division of the lamina, apex form of the pinnule and habitat. Moreover, molecular phylogenetic analysis using the chloroplast rbcL gene suggested that D. wulingshanensis, as the sister group of D. jishouensis, is a monophyletic clade. According to its restricted geographic range, small populations and few individuals, D. wulingshanensis should be considered endangered, according to the IUCN Red List criteria.

GERMINATION OF PORANG (Amorphophalus muelleri) FROM DIFFERENT BULBIL TO VARIOUS PLANTING MEDIA

Porang plant is atubers that havevarious benefits. Porang cultivation needs intensive management through cultivation efforts which of course must be supported by the availability of seeds. Therefore, it is necessary to procure porang seeds from vegetative (tubers) and generative (stem bulbil and branch bulbil). This study aims to obtain the best growing media for porang germination from various types of bulbil. The method used in this study was a factorial randomized block design. The way of working in this research is: Preparation of Seedling Media, Preparation of planting material (Bulbil), Seeding, Maintenance (including watering and weeding). The results showed that there was no significant interaction between the planting medium and the type of bulbil, the media had no significant effect on all observed variables, while the bulbil had a significant effect on the percentage of germination growth, stem height, and number of leaves. The best type of bulbil for breeding is stem bulbil which is superior to the variables of plumule emergence time, petiole length, stem height, and number of leaves compared to branch bulbil. Meanwhile, the best growing media in porang nurseries was a mixture of 50% husk charcoal + 50% sawdust on the variables when the plumule appeared, the percentage of germination, petiole length and stem height. The appearance of bulbil from stems on a mixture of 50% husk charcoal + 50% sawdust media, namely the time of emergence of plumules (5.61 days), percentage of sprouting (86.67%), petiole length (8.72 cm), height stems (31.11 cm) and number of leaves (7.72 strands).

Morphological Variation in Scarlet Plume (Euphorbia fulgens Karw ex Klotzsch, Euphorbiaceae), an Underutilized Ornamental Resource of Mexico with Global Importance

Morphological variation is useful in conservation and genetic improvement programs. Euphorbia fulgens, a range-restricted local endemic species of Mexico, is used locally during the altars in the festivities of different saints and is also cultivated as an ornamental plant mainly in Europe. Thus, in the present study, morphological variation was evaluated in wild populations and cultivated populations. Characterization of 90 individuals from three wild populations (the only ones recorded to date) was done by measuring 30 morphological traits both vegetative and reproductive. Thereafter, seeds were collected, and established under greenhouse conditions, and 39 morphometric variables were evaluated in adult plants. An analysis of variance (ANOVA) was done for wild and cultivated groups independently, and when significant differences were found, Tukey’s comparison of means was applied (p < 0.05). To identify the traits responsible for the differences between wild and cultivated groups, a linear discriminant analysis (LDA) was conducted. Morphological variation was found among wild populations, and this variation decreased in cultivated populations, mainly in reproductive structures. The LDA separated the wild populations from the cultivated groups, according to inflorescence length, petiole length/blade length ratio, and leaf roundness. The variables that determined the separation of individuals between wild and cultivated populations were cyme number, foliar Feret diameter, and inflorescence length, variables that can be important for breeding strategies and artificial selection.

Variation in waterlogging response among ecotypes of Trifolium subterraneum ssp. yanninicum and their relationships with site of origin

Background and AimsIn the annual pasture legume Trifolium subterraneum, ssp. yanninicum exhibits higher waterlogging tolerance than ssp. brachycalycinum and ssp. subterraneum. This study investigates waterlogging tolerance within ssp. yanninicum ecotypes and explores correlations with seedling phenotypic traits and site of origin eco-geographic variables.MethodsTwenty eight diverse ssp. yanninicum ecotypes collected from the Mediterranean region and four cultivars were grown in a controlled environment glasshouse. After 14 days of growth seedling traits were measured. After 21 days of growth, free-drained (control) and waterlogged treatments were imposed for 28 days. Eco-geographic variables were generated from ‘WorldClim’ using collection site locations.ResultsUnder waterlogging, shoot relative growth rate (RGR) ranged from 87–108% and root RGR ranged from 80–116% of controls. Waterlogging reduced shoot dry weight (DW) in four of 32 genotypes, while root DW was reduced in 13 genotypes. Leaf size was maintained, or even increased, under waterlogging in 31 genotypes. However, petiole length was more affected by waterlogging and has value as a waterlogging tolerance indicator. Waterlogging tolerance was not significantly correlated with seedling DW, flowering time or precipitation at the site of origin, while shoot growth under waterlogging had a positive correlation with summer temperatures at origin.ConclusionsGenotypes of ssp. yanninicum tolerated transient waterlogging and greater tolerance was observed among ecotypes, rather than cultivars. An easy-to-measure indicator of tolerance was found in petiole length reduction. This study highlights untapped genotypic variability for breeders to improve the productivity and persistence of ssp. yanninicum under waterlogging.

Quantitative trait loci (QTL) analysis of leaf related traits in spinach (Spinacia oleracea L.)

Background Spinach (Spinacia oleracea L.) is an important leafy vegetable crop, and leaf-related traits including leaf length, leaf width, and petiole length, are important commercial traits. However, the underlying genes remain unclear. The objective of the study was to conduct QTL mapping of leaf-related traits in spinach. Results A BC1 population was used to construct the linkage map and for QTL mapping of leaf length, leaf width, petiole length, and the ratio of leaf length to width in 2015 and 2019. Two genetic linkage maps were constructed by specific locus amplified fragment sequencing (SLAF-seq), and kompetitive allele specific PCR (KASP) technology, respectively using BC1 population in 2015. Based on the results of 2015, the specific linkage groups (LG) detected QTLs were generated using BC1 population in 2019. A total of 13 QTLs were detected for leaf-related traits, only five QTLs being repeatedly detected in multiple years or linkage maps. Interestingly, the major QTLs of leaf length, petiole length, and the ratio of leaf length to width were highly associated with the same SNP markers (KM3102838, KM1360385 and KM2191098). A major QTL of leaf width was mapped on chromosome 1 from 41.470−42.045 Mb. And 44 genes were identified within the region. Based on the GO analysis, these genes were significantly enriched on ribonuclease, lyase activity, phosphodiester bond hydrolysis process, and cell wall component, thus it might change cell size to determine leaves shape. Conclusions Five QTLs for leaf-related traits were repeatedly detected at least two years or linkage maps. The major QTLs of leaf length, petiole length, and the ratio of leaf length to width were mapped on the same loci. And three genes (Spo10792, Spo21018, and Spo21019) were identified as important candidate genes for leaf width.

Evaluation of M3 lines of sesame (Sesamum indicum L.) for vegetative parameters

Vegetative parameters of eight M3 (third mutant generation) lines of sesame were evaluated under rain fed condition. The seeds of the lines were sown alongside their respective controls using a randomized complete block design. The eight lines were generated from three parental stocks: NCRIBEN-04E (V1), NCRIBEN-01M (V2) and NCRIBEN-03L (V3). The three parental stocks were exposed to different doses of gamma irradiation from cobalt-60 source. 04E-550-G2-3 had the highest plant height (57.40) at the 6th week which was significantly different (P<0.05) from the three checks. 03L-450-G2-2 had the highest petiole length (12.45cm) which was significantly different (P<0.05) from the checks except check three (12.25cm) which was not significantly different (P>0.05). 03L-450-G1-2 had the highest number of leaves (91) and consequently highest number of branches (5.60). Although the number of leaves were significantly different (P<0.05) from Check three (54.60), there was no significant difference (P>0.05) between the number of branches and check three (5.40). The results obtained for vegetative parameters of M3 lines of sesame suggests that some of the genotypes could be used as potential parents for future breeding programmes aimed at improving sesame lines.