Plant morphology

About: Plant morphology is a research topic. Over the lifetime, 1174 publications have been published within this topic receiving 24418 citations. The topic is also known as: phytomorphology & morphology of higher plants.

Structural and physiological sexual dimorphism estimated from three-dimensional virtual trees of yerba-mate (Ilex paraguariensis) is modified by cultivation environment

Abstract: Yerba-mate is a subtropical, evergreen, dioecious, South American tree. Sexual dimorphism in photosynthesis, leaf allometry and foliage distribution was hypothesised. Virtual trees (constructed in VPlants software from detailed measurements of plant morphogenesis) of the two genders were compared considering two contrasted cultivation environments and three developmental stages. The total crown volume, leaf area per plant (LA), leaf area index (LAI) and leaf area density (LAD) were calculated. The light interception and photosynthesis were computed from mock-ups in VegeSTAR. Structural sexual dimorphism concerned general plant form, internode length, leaf allometry, leaf surface, pattern of leaf area distribution and LAD. Cultivation environment and developmental stage acted strongly on sex expression of all observed structural parameters and physiological stages. Sexual differentiation in LA and light interception was related to leaves positioned in the lowest layers (150 cm above ground), whereas sexual specialisation in leaf and plant photosynthesis was related to early vegetative and reproductive stages. Several sexual responses strongly depended on the environment, especially light conditions, with opposite effects observed on female and male plants whether they were cultivated in monoculture or in forest understorey, under highlight condition or low-light condition, respectively. Optimised foliage structure and physiology in females may compensate for greater reproductive costs in early developmental stages, but females and males equalise in photosynthetic efficiency after 2-year regrowth.

In vitro plant regeneration as a tool to improve ornamental characters in Passiflora species.

Abstract: The genus Passiflora, comprising about 500 species of vines, lianas and small trees, is the largest in the passion flower family (Passifloraceae). In the tropical and subtropical regions, several species are grown for their edible fruits (Passiflora edulis Sims.), while many others are cultivated in the warmer parts of the world, either outdoors or in the greenhouses, for their medicinal and ornamental value. Passiflora exhibits some unique floral traits, which are of particular interest to the floricultural market. With the aim to exploit the ornamental traits of some Passiflora species, a collection was settled at the CRA-FSO, in Sanremo. Tissue culture protocols were established for Passiflora hybrids 'Guglielmo Betto' and 'Manta', P. trifasciata Lemaire and P. foetida L. 'Hastata'. The in vitro regenerated plants were successfully acclimatized in the greenhouse. At flowering, P. 'Guglielmo Betto', P. 'Manta' and P. trifasciata plants, regenerated from tendrils, were similar to the mother plants concerning plant habit, flower shape, colour and form of leaves. P. foetida 'Hastata' plants which regenerated from immature-flowers showed morphological alterations in the flower and in the fruit involucral bracts. The reduced bracts left the fruit completely visible, conferring a new attractive phenotype. The modification is maintained in the cutting-derived plants.

Growth response of maize plants (Zea mays L.) to wheat and lentil pre-cropping and to indigenous mycorrhizae in field soil

Abstract: The presence of indigenous mycorrhizal fungi may have significant effects on the growth and on the root morphology of plants, under arid and semi arid soil conditions. Lentil and wheat are the traditional crops grown in Southeastern Turkey. In this study soil samples from the Harran plain were collected from the 0-15 cm surface layer under wheat or lentil crop residues and used in a pot experiment carried out under greenhouse conditions with four levels of P fertilization: 0, 20, 40 and 80 mg kg ‐1 soil as Ca(H2PO4)2. Half of the soil batches were submitted to a heating treatment (80°C, 2 h). The maize variety PX-9540 was grown in the pots for 57 days. At harvest, plant dry weight, root length, P and Zn concentrations in plant tissues were measured and the extent of root colonization by arbuscular mycorrhizal fungi (AMF) was determined. Results showed that maize plants grown in soils where lentil had been previously cultivated grew better than those grown after wheat cultivation. In both cases, P concentration in plant tissues increased with increased P fertilization. There were no significant differences in root AMF colonization between soils with different crop sequences, nor with soils submitted to high temperature. Previous crops had a significant influence on the growth of plants that could be related to differences in the indigenous mycorrhiza inoculum potential and efficacy that can promote P uptake and benefit plant growth.