The effect of Citrus tristeza virus (CTV) infection on photosynthetic activity and antioxidant metabolism was analysed in plants of the highly susceptible citrus genotype Mexican lime (Citrus aurantifolia). Two virus isolates differing in their virulence (the severe T318 and the mild T385) were used in the experiments. CTV infection caused a reduction in photosynthetic capacity in infected plan…
Global warming has become one of the major challenges in maintaining global food security. This paper reviews the impacts of climate change on fourteen strategic crops for eight sub- Saharan Africa countries. Climate change is projected to increase median temperature by 1.4–5.5°C and median precipitation by −2% to 20% by the end of the 21st century. However, large levels of uncertaint…
The two field trials evaluated the performance of sesame (var. PBTil) and sunflower (var. Isaanka) intercropped with cassava (var. TMS 30572 and TME 1) in a cassava-based cropping system with a view to studying the phenology of the component crops and establishing mixture productivity in terms of biological efficiency (land equivalent ratio [LER] and area time equivalency ratio [ATER]), in…
There is a broad literature on the impact of Bt cotton adoption in different countries, but few studies have explicitly looked at environmental and health effects from an economic perspective. We analyse the impact of Bt cotton on environmental efficiency in Pakistan, using farm survey data and a doubly heteroskedastic stochastic production function framework. Negative environmental and health…
Water stress is one of the major abiotic stresses that adversely affect cotton production. Seedlings of 142 backcross inbred lines (BILs) derived from Pima cotton ‘Pima S-7’ (Gossypium barbadense L.) 9 Upland cotton ‘Sure-Grow 747’(G. hirsutum L.) were evaluated in two tests for plant height, fresh shoot weight and root weight under two treatments (5% PEG and water-control conditions) …
The sensitivity of photosynthetic metabolism to temperature has been identified as a key uncertainty for projecting the magnitude of the terrestrial feedback on future climate change. While temperature responses of photosynthetic capacities have been comparatively well investigated in temperate species, the responses of tropical tree species remain unexplored. We compared the responses …
As the result of intensive research and breeding efforts over the last 20 years, the yield potential and yield quality of cereals have been greatly improved. Nowadays, yield safety has gained more importance because of the forecasted climatic changes. Drought and high temperature are especially considered as key stress factors with high potential impact on crop yield.Yield safety can only be im…
Introduction – Plants from the Lamiaceae family have been known traditionally for their beneficial health-promoting properties, attributed to their anti-inflammatory, anaesthetic and anti-microbial effects. Objective – The purposes of this study was to characterise the essential oils from four Lamiaceae plants by applying different extraction techniques. Methods – Accelerated solven…
Loss and fragmentation of natural ecosystems are widely recognized as the most important threats to biodiversity conservation, with Neotropical dry forests among the most endangered ecosystems. Area and edge effects are major factors in fragmented landscapes. Here, we examine area and edge effects and their interaction, on ensembles of arthropods associated to native vegetation in a fragmented …
The purpose of this study was to investigate the reproductive cycle of a highelevation population of Aspidoscelis costata costata (1500–1600 m) and compare its reproductive cycle with that of other populations, species, and closely related genera. Adult male A. costata costata lizards were collected, and the reproductive tracts were removed and subjected to histological analyses. Testicular …
This book covers key areas in agricultural science, namely crop improvement, production, response to water, nutrients, and temperature, crop protection, agriculture and human health, and animal nutrition. The contributions by the authors include manipulation of the variables and genetic resources of inheritance of quantitative genes, crop rotation, soil water and nitrogen, and effect of tempera…
The present book is a collection of ten original research articles and reports, associated with selected topics in agricultural chemistry. The discussed issues are organized in four sections: Classification and labeling of active substances in plant protection products, Environmental and stress plant physiology and behavior, Antimicrobial and antioxidant potential of plant extracts, and Polluta…
Background and Aims Specific leaf area (SLA), a key element of the ‘worldwide leaf economics spectrum’, is the preferred ‘soft’ plant trait for assessing soil fertility. SLA is a function of leaf dry matter content (LDMC) and leaf thickness (LT). The first, LDMC, defines leaf construction costs and can be used instead of SLA. However, LT identifies shade at its lowest extreme and succul…
Background and Aims Plants are able to adapt to the environment dynamically through regulation of their growth and development. Excess copper (Cu2+ ), a toxic heavy metal, induces morphological alterations in plant organs; however, the underlying mechanisms are still unclear. With this in mind, the multiple signalling functions of nitric oxide (NO) in plant cells and its possible regulatory r…
Organic farming is an environmental friendly ecosystem management in which, use of all kinds of synthetic inputs are eliminated. The area delineated for" organic farming" forbids use of synthetic fertilizers, pesticides, genetically modified seeds (GMO) and breeds, etc. These are replaced with site-specific management system that maintain and increase long-term soil fertility and prevent …
Large portions of the Great Basin become degraded and disturbed every day due to natural and human-induced causes. Some disturbed areas may recover naturally in time, but other areas may never recover naturally because invasive weeds establish quickly and prevent native plants from establishing. Invasive weeds can potentially spread into adjacent, healthy landscapes where they can threaten loc…
The formation, dispersal, and germination of seeds are crucial stages in the life cycles of gymnosperm and angiosperm plants. The unique properties of seeds, particularly their tolerance to desiccation, their mobility, and their ability to schedule their germination to coincide with times when environmental conditions are favorable to their survival as seedlings, have no doubt contributed s…
Insects are often considered a nuisance to human beings and mere pests for crops and animals. Yet this is far from the truth. Insects provide food at low environmental cost, contribute positively to livelihoods, and play a fundamental role in nature. However, these benefits are largely unknown to the public. Contrary to popular belief, insects are not merely “famine foods” eaten in time…
Background and Aims The herbivore defence system of true grasses (Poaceae) is predominantly based on silicon that is taken up from the soil and deposited in the leaves in the form of abrasive phytoliths. Silicon uptake mechanisms can be both passive and active, with the latter suggesting that there is an energetic cost to silicon uptake. This study assessed the effects of plant-available soil …
Background and Aims The cell cycle-regulated protein ENDOSPERM DEFECTIVE 1 (EDE1) is a novel plant microtubule-associated protein essential for plant cell division and for microtubule organization in endosperm. EDE1 is only present on microtubules at mitosis and its expression is highly cell cycle regulated both at the protein and the transcript levels. Methods To search for EDE1-interacting …
Background and Aims Hydration, rupture and exine opening due to the sudden and large expansion of intine are typical of taxoid-type pollen grains. A hemispheric outgrowth external to the exine was observed on Cupressus and Juniperus pollen grains before the intine swelling and exine release. However, the actual existence of this permanent or temporary structure and its precise role in pollen hy…
Background and Aims The closely related NAC family genes NO APICAL MERISTEM (NAM) and CUPSHAPED COTYLEDON3 (CUC3) regulate the formation of boundaries within and between plant organs. NAM is post-transcriptionally regulated by miR164, whereas CUC3 is not. To gain insight into the evolution of NAM and CUC3 in the angiosperms, we analysed orthologous genes in early-diverging ANA-grade angiospe…
Background The initiation of DNA replication is a very important and highly regulated step in the cell division cycle. It is of interest to compare different groups of eukaryotic organisms (a) to identify the essential molecular events that occur in all eukaryotes, (b) to start to identify higher-level regulatory mechanisms that are specific to particular groups and (c) to gain insights into th…
Background and Aims Anthropogenic depletion of stratospheric ozone in Arctic latitudes has resulted in an increase of ultraviolet-B radiation (UV-B) reaching the biosphere. UV-B exposure is known to reduce aboveground biomass and plant height, to increase DNA damage and cause accumulation of UV-absorbing compounds in polar plants. However, many studies on Arctic mosses tended to be inconclusive…
Background and Aims During sexual reproduction in higher angiosperms, the pollen tubes are directed to the ovules in the pistil to deliver sperm cells. This pollen tube attraction is highly species specific, and a group of small secreted proteins, TfCRPs, are necessary for this process in Torenia fournieri. Methods A candidate pollen tube attractant protein in Torenia concolor, a related spec…
Background and Aims Manipulation of plant structure can strongly affect light distribution in the canopy and photosynthesis. The aim of this paper is to find a plant ideotype for optimization of light absorption and canopy photosynthesis. Using a static functional structural plant model (FSPM), a range of different plant architectural characteristics was tested for two different seasons in orde…
Background and Aims Most studies dealing with light partitioning in intercropping systems have used statistical models based on the turbid medium approach, thus assuming homogeneous canopies. However, these models could not be directly validated although spatial heterogeneities could arise in such canopies. The aim of the present study was to assess the ability of the turbid medium approach to …
Background and Aims Most cooking banana and several desert bananas are interspecific triploid hybrids between Musa acuminata (A genome) and Musa balbisiana (B genome). In addition, M. balbisiana has agronomical characteristics such as resistance to biotic and abiotic stresses that could be useful to improve monospecific acuminata cultivars. To develop efficient breeding strategies for improvin…
Background and Scope In eukaryotes, chromatin remodelling complexes are shown to be responsible for nucleosome mobility, leading to increased accessibility of DNA for DNA binding proteins. Although the existence of such complexes in plants has been surmised mainly at the genetic level from bioinformatics studies and analysis of mutants, the biochemical existence of such complexes has remained …
Background and Aims Density is a crucial variable in forest and wood science and is evaluated by a multitude of methods. Direct gravimetric methods are mostly destructive and time-consuming. Therefore, faster and semito non-destructive indirect methods have been developed. Methods Profiles of wood density variations with a resolution of approx. 50 mm were derived from one-dimensional resistanc…
Background and Aims The TCP family is an ancient group of plant developmental transcription factors that regulate cell division in vegetative and reproductive structures and are essential in the establishment of flower zygomorphy. In-depth research on eudicot TCPs has documented their evolutionary and developmental role. This has not happened to the same extent in monocots, although zygomorph…
Background and Aims Peripheral populations of plant species are often characterized by low levels of genetic diversity as a result of genetic drift, restricted gene flow, inbreeding and asexual reproduction. These effects can be exacerbated where range-edge populations are fragmented. The main aim of the present study was to assess the levels of genetic diversity in remnant populations of Hypop…
Background and Aims Forest tree saplings that grow in the understorey undergo frequent changes in their light environment to which they must adapt to ensure their survival and growth. Crown architecture, which plays a critical role in light capture and mechanical stability, is a major component of sapling adaptation to canopy disturbance. Shade-adapted saplings typically have plagiotropic stem…
Background and Aims Seed persistence in the soil under field conditions is an important issue for the maintenance of local plant populations and the restoration of plant communities, increasingly so in the light of rapidly changing land use and climate change. Whereas processes important for dispersal in space are well known, knowledge of processes governing dispersal in time is still limited. …
Background The palm family occurs in all tropical and sub-tropical regions of the world. Palms are of high ecological and economical importance, and display complex spatial patterns of species distributions and diversity. Scope This review summarizes empirical evidence for factors that determine palm species distributions, community composition and species richness such as the abiotic environm…
Background and Aims Aluminium (Al) toxicity is one of the factors limiting crop production on acid soils. However, genotypic differences exist among plant species or cultivars in response to Al toxicity. This study aims to investigate genotypic differences among eight cultivars of tatary buckwheat (Fagopyrum tataricum) for Al resistance and explore the possible mechanisms of Al resistance. Me…
Background and Aims Vegetation has long been recognized to protect the soil from erosion. Understanding species differences in root morphology and functional traits is an important step to assess which species and species mixtures may provide erosion control. Furthermore, extending classification of plant functional types towards root traits may be a useful procedure in understanding important…
Background and Aims Flower morphology and inflorescence architecture affect pollinator foraging behaviour and thereby influence the process of pollination and the reproductive success of plants. This study explored possible ecological functions of the lever-like stamens and the floral design in Salvia cyclostegia. Methods Flower construction was experimentally manipulated by removing either t…
Background and Aims Why are sterile anthers and carpels retained in some flowering plants, given their likely costs? To address this question, a cryptically dioecious species, Petasites tricholobus, in which male and female plants each have two floret types that appear pistillate and hermaphroditic, was studied. The aim was to understand the function of sterile hermaphroditic florets in females…
Background and Aims The presence of fruit has been widely reported to act as an inhibitor of flowering in fruit trees. This study is an investigation into the effect of fruit load on flowering of ‘Moncada’ mandarin and on the expression of putative orthologues of genes involved in flowering pathways to provide insight into the molecular mechanisms underlying alternate bearing in citrus. Me…
Background and Aims Nitrogen turnover within plants has been intensively studied to better understand nitrogen use strategies. However, differences among the nitrogen absorbed at different times are not completely understood and the fate of nitrogen absorbed during winter is largely uncharacterized. In the present study, nitrogen absorbed at different times of the year (growing season, winter a…
Background and Aims A test was made of the hypothesis that papilionate legume flowers filter pollinators according to their ability to exert strength to open flowers to access rewards. In addition, interactions with pollen vectors were expected to explain the structural complexity of the architecture of these flowers since operative flower strength may be determined by a combination of morphol…
Background and Aims Interspecific Diphasiastrum hybrids have been assumed to be homoploid and to produce well-formed spores serving sexual reproduction. If this were the case, forms intermediate between hybrids and parents or hybrid swarms should be expected. The purpose of this study was: (1) to check whether homoploidy consistently applies to the three hybrids throughout their Central Europe…
Background The common primrose, Primula vulgaris, along with many other species of the Primulaceae, exhibits floral heteromorphy in which different individuals develop one of two possible forms of flower, known as pin and thrum. Both flower types are hermaphrodite and exhibit reciprocal positions of male and female reproductive structures, which together with a sporophytic incompatibility syste…
Background and Aims Dimorphism among floral traits can evolve through variation in selection intensity between female and male performance, especially when sex functions are separated between flowers on a plant (monoecy), or between individuals (dioecy). In animal-pollinated species, male floral traits are predicted to be larger because competition for pollinators should favour larger display…
Background and Aims Anaxagorea is the phylogenetically basalmost genus in the large tropical Annonaceae (custard apple family) of Magnoliales, but its floral structure is unknown in many respects. The aim of this study is to analyse evolutionarily interesting floral features in comparison with other genera of the Annonaceae and the sister family Eupomatiaceae. Methods Live flowers of Anaxago…
Background and aims Pollination-induced floral changes, which have been widely documented in flowering plants, have been assumed to enhance the plant’s reproductive success. However, our understanding of the causes and consequences of these changes is still limited. Using an alpine gynodioecious species, Cyananthus delavayi, we investigated the factors affecting floral closure and estimated…
Background New roles for flavonoids, as developmental regulators and/or signalling molecules, have recently been proposed in eukaryotic cells exposed to a wide range of environmental stimuli. In plants, these functions are actually restricted to flavonols, the ancient and widespread class of flavonoids. In mosses and liverworts, the whole set of genes for flavonol biosynthesis – CHS, CHI, F3H…
Background and Aims The amount of data collected previously for Velloziaceae neither clarified relationships within the family nor helped determine an appropriate classification, which has led to huge discordance among treatment by different authors. To achieve an acceptable phylogenetic result and understand the evolution and roles of characters in supporting groups, a total evidence analysis …
Background and Aims A wheat cultivar, Triticum aestivum ‘Hong Mang Mai’, shows tolerance to deep-sowing conditions by extreme elongation of the first internode, likely mediated by the gibberellin (GA) response. To understand factors involved in the response of this deep-sowing-tolerant cultivar, cell expansion and division that confer elongation on the first internodes of wheat seedlings w…