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The Agrobacterium-mediated floral dip protocol is the most extensively used transformation method for a model plant Arabidopsis thaliana. Several useful methods for Agrobacterium tumefaciens–mediated transformations of Arabidopsis are existing, but they are time consuming and with low transformation efficiency. Here, we developed a transgenic Arabidopsis lines TET12p::TET12-RFP in a short period of time and enhanced transformation efficiency by using a modified transformation method by applying drought stress after floral dip. In this protocol, Agrobacterium cells carrying TET12p::TET12-RFP recombinant vectors were resuspended in a solution of 5% sucrose, 0.05% (v/v) silwet L-77 to transform female gametes of developing Arabidopsis inflorescences. Treated Arabidopsis were then applied with different levels of drought stresses to stimulate plants for the utilization of maximum plant energy in seed maturation process. The applied stresses achieved the fast maturation of already treated inflorescences while stopped the growing of newly arising untreated inflorescence, thus decreased the chances of wrong collection of untransformed seeds. Consequently, the collected seeds were mostly transgenic with a transformation frequency of at least 10%, thus the screening for positive transformants selection was more advantageous on a selective medium as compared to a classical floral dip method. Within 2-3 months, two hundred of individual transgenic plants were produced from just 10 infiltrated plants. This study concludes that application of drought stresses in a specific stage of plant is a beneficial strategy for achieving the transgenic Arabidopsis in a short period of time with high transformation efficiency.

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Phenomic characterization through digital imaging (DI) can capture the three dimensional variation in wheat grain size and shape using different image orientations. Digital imaging may help identifying genomic regions controlling grain morphology using association mapping with simple sequence repeats (SSRs) markers. Accordingly, seed shape phenotypic data of a core collection of 55 wheat genotypes, previously characterized for osmotic and drought tolerance, were produced using computer based Smart grain software. Measured dimensions included seed volume, area, perimeters, length, width, length to width ratio, circularity, horizontal deviation from ellipse (HDEV), vertical deviation from ellipse (VDEV), factor form density (FFD) etc. The thousand grain weight (TGW) was positively correlated with grain size direct measurements; however, VDEV, FFD and other derived grain attributes showed no or negative correlation with TGW. Digital imaging divided the genotypes correctly into well-defined clusters. The wheat genotypes studied were further grouped into two sub-clusters by the Bayesian structure analysis using unlinked SSR markers. A number of loci over various chromosomal regions were found associated to grain morphology by the genome wide analysis using mixed linear model (MLM) approach. A considerable number of marker-trait associations (MTAs) on chromosomes 1D and 2D may carry new alleles with potential to enhance grain weight due to the use of untapped wild accessions of Aegilops tauschii. Conclusively, we demonstrated the application of multiple approaches including high throughput phenotyping using DI complemented with genome wide association studies to identify candidate genomic regions underlying these traits, which allows a better understanding on molecular genetics of wheat grain weight.

The present study is focused on the detailed foliar epidermal anatomy of some selected wild edible fruits (WEFs) from Pakistan using light microscopy (LM) and scanning electron microscopy (SEM). The studied species are Ficus racemosa L., Solanum nigrum L., Capparis spinosa L., Physalis divaricata D.Don, Rosa moschata Herrm. and Ribes orientale Desf. collected from various localities of Pakistan. The objective of the present study is to investigate qualitative and quantitative anatomical characters for the identification and differentiation of collected wild edible fruits. The characters studied are shape and size of epidermal cells, anticlinal wall pattern, trichome type and shape, average number of stomata, length and width of stomata and pore. The detailed microscopic investigation and variations in the characters recorded have a key role in the determination and authentication of wild edible fruits. This study possesses great potential for plant taxonomists to further evaluate the species at molecular and genetic levels.