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Öğe An effective pest management approach in potato to combat insect pests and herbicide(Springer Verlag, 2019) Amiri A.N.; Bakhsh A.Insect pests and weeds incur significant yield losses to potato crop worldwide. The increasing crop losses provide impetus for the development of pest management strategy that is equally effective against insect pests and weeds. In the present study, a molecular approach was used to develop transgenic potato lines (cv. Marabel) effective against Colorado potato beetle (Leptinotarsa decemlineata Say), potato tuber moth (Phthorimaea operculella Z.) and Basta ® application. Agrobacterium tumefaciens strain EHA105 harboring binary vector pTF101.1 containing cry1Ac gene under the control of 35S and AoPR1 promoters was used to infect leaf discs and internodal explants. Phosphinothrincin was used at optimal concentration (2 mg/l) for the screening of primary transformants. The standard molecular assays exhibited gene integration and expression in putative transgenics. Real-time data revealed up to ninefold high cry1Ac transcript levels, whereas cry protein amount was estimated to 0.4 ppm in primary transformants. The analysis of first tuber progeny showed proper integration cry1Ac and bar genes in subsequent progeny. The transgenic plants also showed tolerance to the application of Basta ® . The efficacy of cry1Ac was evaluated by allowing larvae of Colorado potato beetle (CPB) and potato tuber moth (PTM) to feed on transgenic plants. Results revealed appreciable mortality levels of different larval instars of CPB (20–100%) and PTM (50–100%). Overall, our results exhibit the potential of these transgenic lines to be used in a potato breeding program with the purpose to control insect pests and weeds. © 2019, King Abdulaziz City for Science and Technology.Öğe Aquatic plants as human food(Springer International Publishing, 2018) Aasim M.; Bakhsh A.; Sameeullah M.; Karataş M.; Khawar K.M.[No abstract available]Öğe Biotechnological approaches for genetic improvement of fenugreek (Trigonella foenum-graceum L.)(Springer Singapore, 2018) Aasim M.; Baloch F.S.; Bakhsh A.; Sameeullah M.; Khawar K.M.Abstract Fenugreek (Trigonella foenum-graecum L.) is one of the important medicinal plants of ancient medicinal systems due to its high nutraceutical and pharmaceutical properties. Seeds and leaves of Fenugreek contain phytochemicals like diosgenin and trigonelline. It is a cultivated plant of the modern world for medicinal uses, an edible vegetable, and a forage plant. Advancement in industrial and biotechnological techniques for the isolation of phytochemicals increase the demand of Fenugreek, and its breeding programs are based on improving the secondary metabolites compared to other uses. Recent advancement in modern biotechnological approaches enables researchers to develop elite cultivars of desired traits in a short time. Application of modern techniques like artificial mutations under in vitro conditions, characterization using molecular markers, and development of successful plant tissue culture techniques, genetic transformation techniques, and functional genomics studies have significant potential to improve Fenugreek traits. The study highlights the application of biotechnological approaches used for the development of elite Fenugreek traits for the researchers for future breeding programs. Furthermore, the research gap and areas to improve research have been highlighted in this present study. © Springer Nature Singapore Pte Ltd. 2018.Öğe Development of transgenic tobacco lines with pyramided insect resistant genes(Scientific and Technical Research Council of Turkey, 2018) Bakhsh A.; Dınç T.; Hussain T.; Demırel U.; Aasim M.; Çalişkan M.E.Insect pests are among the major constraints rendering drastic decreases in crop yield. The expression of stacked insecticidal genes in crops can lead to resistance durability and can delay the development of resistance in target insect pests. The present study was designed to introduce an insect resistance trait in locally cultivated Turkish tobacco cultivars (Basma and Nail) with pyramided insecticidal genes. Agrobacterium strain LBA4404 harboring plasmid pKGH4 with cry1Ac and cry2A genes under the control of 35S promoter was used to infect leaf discs of both cultivars; plasmid also contained uidA within the T-DNA region for earlier screening of putative transformants. The overall transformation efficiency was calculated as 30.7% and 18.8% in Basma and Nail, respectively. PCR results confirmed the integration of cry1Ac, cry2A, uidA, and nptII genes in 40 plants of Basma and 16 plants of Nail. ELISA results showed variation in expression of cry1Ac protein among transgenic plants varying from 0.017 to 0.607 µg/g of fresh tissue. Bioassay results with potato tuber moth (Phthorimea operculella Zeller) showed significant mortality of the targeted pest on primary transformants. Furthermore, T1 transgenic progeny exhibited the inheritance of T-DNA in Mendelian as well as non-Mendelian fashion. The results revealed that lines can serve as a source of germplasm in tobacco breeding programs. © TÜBİTAK.Öğe Expression of GNA and biting site-restricted cry1Ac in cotton; an efficient attribution to insect pest management strategies(Springer Tokyo, 2018) Khabbazi S.D.; Khabbazi A.D.; Özcan S.F.; Bakhsh A.; Başalma D.; Özcan S.Insect-resistant transgenic cotton has been commercialized for two decades. Most of the introduced cultivars express Bt gene(s) constitutively under the control of 35S promoter in whole-plant tissues. However, there have been other promoters considered by researchers to confine the toxin expression to targeted organ and tissues. We developed a triple-gene construct including GNA, cry1Ac and cp4 epsps genes. We attempted to confine cry1Ac expression to insect biting sites by cloning it to downstream of a wound-inducible promoter isolated from Asparagus officinalis (AoPR1). Moreover, to broaden the range of resistance, GNA was driven by the 35S promoter to target the sap-sucking insects like aphids which impose large losses in cotton production. To select the transformants in selection medium and for glyphosate tolerance, GNA and cry1Ac genes were accompanied with cp4 epsps gene. Two binary vectors harboring desired genes were constructed and utilized in the study (pGTGNAoC1AC and pGTGN35C1AC). Transformation of cultivar GSN-12 was carried out by employing Agrobacterium tumefaciens strain EHA105. Plantlets were primarily screened under glyphosate (N-phosphonomethyl glycine) selection pressure and subsequently subjected to molecular and biotoxicity assays. Introduction of cry1Ac and GNA to cotton plant conferred resistance to Spodoptera littoralis and Aphis gossypii Glover. Restriction of cry1Ac toxin protein to insect biting sites along with a plant lectin attributes significantly to insect pest management strategies. © 2018, Korean Society for Plant Biotechnology and Springer Japan KK, part of Springer Nature.Öğe Mutation breeding in potato; endeavors and challenges(Pakistan Agricultural Scientists Forum, 2018) Zia M.A.B.; Bakhsh A.; Çalıskan M.E.Mutation breeding is a resolute application of mutations to develop the desired characteristics in crops to get increased yield. Since the first release of mutant potato cultivar in Belgium in 1968, mutation breeding in potato found a niche in plant breeding because of the increased quality and yield improvements. Six mutated potato cultivars have been registered from all over the world. Many scientists are working on potato mutation breeding and have reported appreciable results especially quality improvement of the crop, decreased amylose contents, salt and heat tolerance, and resistance to late blight. However conventionally induced mutation has some distinct limitations, especially in the applications of crop-breeding, as percentage of desired mutation is very less in the field; by using in vitro techniques with the combination of routine mutagenesis has overawed this obstruction too. Thus this technique can be the part of the other plant breeding techniques to increase the yield and to nourish the rapidly increasing world’s population. The present review focuses the achievements, endeavors and future challenges of mutation breeding in potato. © 2018, Pakistan Agricultural Scientists Forum. All rights reserved.Öğe Resistance to cereal cyst nematodes in wheat and barley: An emphasis on classical and modern approaches(MDPI AG, 2019) Ali M.A.; Shahzadi M.; Zahoor A.; Dababat A.A.; Toktay H.; Bakhsh A.; Li H.Cereal cyst nematodes (CCNs) are among the most important nematode pests that limit production of small grain cereals like wheat and barley. These nematodes alone are estimated to reduce production of crops by 10% globally. This necessitates a huge enhancement of nematode resistance in cereal crops against CCNs. Nematode resistance in wheat and barley in combination with higher grain yields has been a preferential research area for cereal nematologists. This usually involved the targeted genetic exploitations through natural means of classical selection breeding of resistant genotypes and finding quantitative trait luci (QTLs) associated with resistance genes. These improvements were based on available genetic diversity among the crop plants. Recently, genome-wide association studies have widely been exploited to associate nematode resistance or susceptibility with particular regions of the genome. Use of biotechnological tools through the application of various transgenic strategies for enhancement of nematode resistance in various crop plants including wheat and barley had also been an important area of research. These modern approaches primarily include the use of gene silencing, exploitation of nematode effector genes, proteinase inhibitors, chemodisruptive peptides and a combination of one or more of these approaches. Furthermore, the perspective genome editing technologies including CRISPR-Cas9 could also be helpful for improving CCN resistance in wheat and barley. The information provided in this review will be helpful to enhance resistance against CCNs and will attract the attention of the scientific community towards this neglected area. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.Öğe Transgenic potato lines expressing hairpin RNAi construct of molting-associated EcR gene exhibit enhanced resistance against Colorado potato beetle (Leptinotarsa decemlineata, Say)(Springer International Publishing, 2019) Hussain T.; Aksoy E.; Çalışkan M.E.; Bakhsh A.Most of the commercialized insect resistant transgenic crops express cry gene(s) isolated from Bacillus thuringiensis; however, intensive cultivation of Bt crops over almost two decades has been questioned regarding its sustainability and durability in pest management. The present study focused on silencing of highly specific molting-associated Ecdysone receptor (EcR) gene of Colorado potato beetle (CPB) using RNA interference (RNAi) approach. The partial cDNA of EcR gene of CPB was amplified using specific primers in sense and anti-sense orientations, and cloned in pRNAi-GG vector flanked by an intronic sequence (pdk). Leaf and internodal explants of Agria and Lady Olympia potato cultivars were infected with Agrobacterium strain LBA4404 harboring constructs under the control of CaMV 35S promoter. Standard molecular analysis of primary transformants showed proper integration of T-DNA in plant genome. The transgenic plants of both cultivars were evaluated for their efficacy against first, second and third instar CPB larvae. The leaf biotoxicity assays revealed 15–80% of CPB mortality. A significantly lower fold-change (0.87–4.14×) in larval weight was observed in insects fed on transgenic plants compared to the ones fed on control plants (1.87–6.53×). Furthermore, CPB larvae fed on transgenic plants exhibited reduced EcR transcripts, indicating the functionality of dsRNA EcR in silencing EcR gene expression. This study is an excellent example of the integration of an alternative, effective and reliable method to cope with potato insect pests that incur significant losses to potato production in the world. © 2019, Springer Nature Switzerland AG.
