Computing Forgotten Topological Index of Extremal Cactus Chains

The F-index is the whole of 3D squares of vertex degrees in a chart G. It as of late turned into the subject of a few investigates because of its extraordinary capability of uses. The point of this paper is to register the F-record of triangular prickly plant chain, square desert flora chains, 6-sided cactus restraints and polyomino restraints. In addition, we decided the extremal chains in the desert plant chains and polyomino fastens as for the F-index.

Adaptive Strategies of Desert Plants in Coping with the Harsh Conditions of Desert Environments: A Review

The low and erratic precipitation of desert habitats and the resultant drought have been a huge environmental challenge to the desert flora. Because these organisms must harmonize their structures and functions to thrive in their environments, they have evolved a range of strategies to survive the drought that characterizes the desert ecosystem. Desert plants have adopted some strategies like drought tolerance, drought escape, and succulence as the means to conserve and use water. Also, to minimize the rate of transpiration, they have evolved leaf sclerophylly. All these adaptations and more, play an important role in the organisms’ ability to conquer the harsh conditions of desert environments amidst the prevailing climate changes. It seems that some of these plants could potentially serve as models for understanding drought adaptation mechanisms and their potential uses. It is expected that understanding the response of plants to increasing drought would be important in the light of global and regional climate changes, not only to forecast population dynamics in natural ecosystems but also to adjust management processes in agronomy and vegetation management for improvement.

Gallant Desert Flora: Olive Pink’s Australian Arid Regions Flora Reserve

In the mid-1950s Olive Pink campaigned to have an area of land in Alice Springs set aside as a flora reserve. In 1956 the area was gazetted as the Australian Arid Regions Flora Reserve, with Pink appointed as honorary curator. Although Pink was not a professional horticulturalist or botanist, she established a garden that marked itself out from contemporary gardens, such as Maranoa Gardens and the Australian National Botanic Gardens, which were similarly committed to showcasing indigenous Australian plants. Pink's approach was pioneering in that she aimed to create a collection of plants selected by a delineated ‘climatic zone' and geographic area rather than drawn from all parts of the continent. This article argues that Pink developed a distinctive form of horticultural work informed by her passion for and close artistic observation of desert flora; her long experience establishing and maintaining gardens under central Australian ecological conditions; along with her anthropological insight into Indigenous knowledge of flora gained through her studies with Arrernte and Warlpiri people. Today we might recognize the principles that informed Pink's garden through the concepts of ‘water-wise gardens' and environmental sustainability practices.

First Report of Euphorbia larica Dieback Caused by Fusarium brachygibbosum in Oman

Euphorbia larica Boiss. (Arabic = Isbaq) is a dominant and common component of the native desert flora of northern Oman. Traditional ethnobotanical uses have included use of the latex for treating camels with parasites. In February 2011, E. larica plants showing stem lesions up to several cm long and in many cases with stem dieback were collected from Al-Khoudh 50 km west of Muscat. The disease appeared widespread within the location where several dead specimens were also recorded, although the cause was unclear. Sections (5 mm) of five diseased branches taken from different plants and placed on potato dextrose agar (PDA) in all cases yielded Fusarium-like colonies. Colonies recovered were initially white becoming rose to medium red in color with abundant aerial mycelium. Macroconidia were scarce and scattered (mean of 20 spores: 26.83 × 4.73 μm) with three to four septa per spore; microconidia were slightly curved, ovoid, and fusiform (mean of 20 spores: 11.64 × 4.03 μm) with zero to two septa per spore. Spherical chlamydospores (mean of 20 spores: 11.05 μm) were terminal and intercalary, single, and in chains. In vitro characters and spores measurements conformed to previously described features of Fusarium brachygibbosum Padwick (1). Mycelial plugs (5 mm) were taken from 7-day-old cultures of the fungus grown on 2.5% PDA and applied to a small incision (3 mm) on the stems of healthy E. larica grown in situ and protected with wet cotton and Parafilm. The residual agar, mycelium, cotton, and Parafilm were removed after 7 days and symptoms were recorded. Control stems were inoculated using PDA (5 mm) plugs alone and inoculations were repeated twice. Artificial inoculations resulted in dieback of all stems within 11 days and fungal colonies identical to initial isolations were recovered from artificially infected surface-sterilized stem pieces. Identification of F. brachygibbosum was confirmed by comparing sequences generated from the internal transcribed spacer (ITS) region of the ribosomal DNA (ITS1 and ITS4 primers) and the intron region of translation elongation factor alpha (EF1-α) (EF-1-986 and EF-728 primers). The ITS and EF1-α sequences were found to share 100% and 99% nucleotide similarity to previously published sequences of the ITS (HQ443206) and EF1-α (JQ429370) regions of F. brachygibbosum in GenBank. The accession number of ITS sequence of one isolate assigned to EMBL-Bank was HF562936. The EF sequence was assigned to EMBL-Bank accession (submission number Hx2000027017; number will be sent later). This pathogen has previously been reported on date palm (2) in Oman but, to our knowledge, this is the first report of this pathogen on E. larica. References: (1) A. M. Al-Sadi et al. Crop Prot. 37:1, 2012. (2) G. W. Padwick. Mycol. Pap. 12:11, 1945.

Plant Ecology of the Namib Desert

The Namib desert is reportedly the oldest desert in the world. It consists of a number of very distinct ecosystems, six of which are dealt with in this text. Among them are the sand dune, the dry river bed and the domed inselbergs vegetation. The importance of fog water absorption for the Namib flora is discussed. Two important and noteworthy endemic plant species, i.e. Welwitschia mirabilis and Acanthosicyos horrida are treated extensively, because of their great interest for plant physiology and ethnobotany, resp. Special attention is given to the importance of the CAM photosynthetic system for Namib desert plant survival. Where possible the ethnobotanic importance of the species is discussed. KEY WORDS: Acanthosicyos horrida. desert flora, drought stress, ethnobotany, succulents, Welwitschia mirabilis