Evaluation of Selected Indian Bread Wheat (Triticum aestivum L.) Genotypes for Morpho-physiological and Biochemical Characterization under Salt Stress Conditions

Wheat is the second most important crop after rice in India and occupies approximately 28.5 million hectare area. Salinity is one of the major factors reducing plant growth and productivity worldwide, and affects about 7% of world’s total land area. In India about 6.73 million hectare land area is salt affected. The aim of this study was to investigate the morpho- physiological and biochemical response of wheat to temporal salinity (ECiw = 10.0 dSm–1) exposures. Ten wheat genotypes were evaluated in two successive growing seasons (2012–2014), with complete randomized design with three replications under both salinity stress and non-stress conditions. The morpho-physiological and biochemical character measured in this investigation, inhibited under both salt stresses (S1 & S2) conditions but much more significantly inhibited under long-term salinity exposure (S2) than S1 because interrupting the metabolic process of plant, resulting in reduced growth and productivity. According to correlation result, selection of high yield genotypes can be done based on plant height (0.649*), tiller plant–1 (0.808**) and leaf area (0.687*). The multivariate morphophysiological and biochemical parameters should be further used to develop salinity tolerance in wheat breeding improvement programmes

Osmolytes: Proline metabolism in plants as sensors of abiotic stress

Proline accumulation occurs in a large range of plant species in retaliation to the numerous abiotic stresses. An exclusive research pattern suggests there is a pragmatic relation between proline accumulation and plant stress tolerance. In this review, we will discuss the metabolism of proline accumulation and its role in stress tolerance in plants. Pertaining to the literature cited clearly indicates that not only does it acts as an osmolyte, it also plays important roles during stress as a metal chelator and an antioxidative defence molecule. Moreover, when applied exogenously at low concentrations, proline enhanced stress tolerance in plants. However, some reports point out adverse effects of proline when applied at higher doses. Role of proline gene in seed germination, flowering and other developmental programmes; thus creation of transgene overexpressing this gene would provide better and robust plants. In this context this review gives a detailed account of different proline gene over-expressed in all the trans-genic crops so far

In vitro effect of polyethylene glycol and sorbitol on two banana varieties viz. Grand naine and Nalla bontha to study drought stress

Water stress is one of the foremost categories of stress damaging plants’ overall growth and development. The aim of the present study was to explore and demonstrate stress-induced drought to calibrate changes in stress parameters of two banana plant varieties viz. Grand naine (G9)  and Nalla bontha were cultured in Murashige and Skoog medium (MS) media supplemented with stress inducers -Poly ethylene glycol (PEG)  and sorbitol. The different concentrations of inducers were used to induce drought stress in two varieties of banana with contrasting characters for drought condition. The study indicated that PEG contrived mild to moderate osmotic stress and so does the alditol i.e. sorbitol on in vitro banana plants.  The different concentrations of PEG and sorbitol produced significant effects on various parameters. The maximum decrease in shoot length was prominent in G9(52%) as compared to Nalla bontha (11%). When treated with 3% w/v sorbitol, even average root length showed the same level of damage with G9(59%) while in case of Nalla bontha there  was  a 17% decrease. The banana plantlet produced in vitro was estimated at one and two weeks after inoculation, respectively. Proline content tended to increase as the concentration of osmotic inducers increased (-44 % in G9 at 3% w/v sorbitol), whereas RWC (8.9% in G9 at 3% w/v Peg) showed an opposite effect. It was concluded that quantitative and qualitative changes in physiological (shoot and root length) and biochemical (Proline and relative water content, RWC) parameters played an important role in plants under drought stress conditions. This pattern varied from species to species. This work has been attempted for the first time in banana, especially Grand naine varieties with contrasting characters under induced drought stress.

Banded leaf and sheath blight: A menacing disease of maize (Zea mays L.) and its management

Maize (Zea mays L.) crop is attacked by number of fungal, bacterial and viral diseases, out of which banded leaf and sheath blight (BLSB) caused by anastomosis group 1-IA of Rhizoctonia solani f. sp. sasakii Exner. is one of the most widespread and destructive disease of maize in Southeast Asian countries. The occurrence of this disease has also been reported from other parts of the world, which causes significant yield loss up to 100%. R. solani can survive in the soil for several years and able to infect plants belonging to more than 32 families, including many economically important monocots and dicots plants. The severity of the disease favoured by humid weather with temperature around 28°C, poses challenge to maize growers due to its soil borne nature and lack of resistance cultivars. It is indicated that none of the disease management approaches are effective against BLSB. Banded leaf and sheath blight is difficult to control through either fungicide or crop rotation alone. A number of quantitative trait loci (QTLs) controlling BLSB have been identified that would help the development of maize hybrids resistance to this disease. Management of BLSB requires an integrated approach based on the knowledge of each stage of the disease and molecular aspect of maize defence responses against R. solani. Mention conclusion statement and novelty of the work. The present review summarizes consolidated information on distribution, yield loss, symptoms, pathogen life cycle, epidemiology, genetic structure of the pathogen population, molecular aspect of pathogenicity and its integrated management through cultural, biological, chemical and genetic means. The consolidated knowledge presented in this review should help better disease management and reduce crop yield loss due to banded leaf and sheath blight pathogen

Optimization of culture conditions for high frequency in vitro shoot multiplication in sugarcane (Saccharum officinarum L.)

Present study deals with the optimization of various culture conditions for initiating high frequency in vitro shoot multiplication in two early maturing high yielding sugarcane genotypes namely Co98014 & Co89003. On the behalf of the findings of this study, it was concluded that the temperature, photoperiod and culture media pH affected the frequency of in vitro shoot multiplication in both sugarcane genotypes at a significant level. In both genotypes high frequency shoot multiplication was recorded at growth room temperature 25ºC, 16h/8h light/dark photoperiod and culture media pH 6.0. Genotype Co89003 exhibited highest shoot regeneration and multiplication under various culture conditions. The present study suggests the necessity of investigation of these culture conditions separately upon individual sugarcane genotypes prior to develop efficient in vitro plant regeneration protocol for commercial purposes

Assessment of genetic diversity in bread wheat (Triticum aestivum L.) using RAPD markers

The present study aimed to evaluate the genetic diversity of 10 wheat cultivars by Random Amplified Pol-ymorphic DNA (RAPD) marker. The genomic DNA of 10 wheat genotypes were amplified with 10 RAPD primers that produced 53 amplified band, out of which 23 band were polymorphic (43.39%). The number of fragment amplified per primer ranged from 4 to 9. Primer A01 generated maximum number of amplified band, out of which 5 band were polymorphic. Cluster analysis of wheat genotypes were based on UPGMA method. Cluster analysis of 10 wheat genotypes were classified in to two main group; single variety AKW 1071 was placed in first group and rest 9 variety were placed in second group. The pair wise similarity values ranged from 0.58% to 100% and showed that cultivars Raj-3765 and K-7903 were the closest with highest similarity value (100%), while genotypes AKW 1071 and K9006 showed minimum similarity value (62%). The present study indicated the presence of high genetic diversity among wheat cultivars, which could be used for the developing core collection of wheat germplasm for breeding purpose

Identification of salt tolerant sugarcane cultivars through phenotypic, physiological and biochemical studies under abiotic stress

Sugarcane is one of the typical glycophyte grass plant which can poorly thrive in saline soil profiles of tropics and subtropics globally. Salt stress is a major physiological constrain drastically influencing plant growth and development. Identification of salt-tolerant cultivars can make a substantial contribution to greater productivity of sugarcane in salt stress prone areas. Based upon descriptive phenotypes 38 sugarcane cultivars were included in the present study. Cultivars evaluated in pots at formative and grand growth stages of development under 8 dSm−1 levels of salts (NaCl, Na2SO4, CaCl2·2H2O; 1:2:1 ratio) during two consecutive cropping seasons. Key morphological, physiological and biochemical traits were measured under different levels of salt stress. Recorded data was converted into relative salt tolerance indices (RSTI) for comparative study among genotypes for salt tolerance with multiple agronomic traits. Significant variations were observed between the cultivars at the both growth stages. RSTI for all the studied traits varied considerably such as; for proline contents it was calculated lowest (102.7) in Co 0239 and highest (287.2) in Co 7717 cultivar. Considering the salt tolerance indices derived from morphological, physiological, and biochemical observations indicated that 13 sugarcane cultivars were tolerant, while 13 moderately tolerant and rest 12 cultivars were not capable to grow optimally in salinity and showed susceptibility to salt stress. The tolerance rank of an individual cultivar was based on genotype rank (GR) determined with RSTI and ward’s minimum variance of studied parameters. GR ranged from 1 to 3, wherein GR 1 denotes tolerant, GR 2 moderate and GR 3 for susceptible to salt stress. To conclude, salt tolerant cultivars identified and salt tolerance-associated traits can be exploited in breeding programs to improve sugarcane production in saline areas

Assessment of diversity by using morphological, biochemical and molecular approaches of selected basmati rice (Oryza sativa L.) varieties

The study investigates the genetic diversity among the Basmati rice genotypes. Selected nine Basmati rice genotypes were studied for twelve morphological traits, biochemical parameters and for molecular analysis with 11 SSR markers. Pusa Sugandha 5 and Basmati 370, showed strong aroma while other varieties showed medium aroma. Alkali spreading value were intermediate in Basmati 386, Vallabh Basmati 22 and Vallabh Basmati 24 while other varieties showed high values. Pusa Basmati 1 and Basmati 386 showed soft category of gel consistency while in rest varieties it was under medium category. Amylose percentage in grains were ranged from 18.02% (Taraori basmati) to 22.0% (Basmati370). Molecular analysis with 11 SSR markers showed 125 allels with an average number of allels 11.36 per locus. All the markers showed specific type of banding pattern along with 82 polymorphic allels in different genotypes. This study focuses on application of statistical methods and techniques in analysis of genetic diversity of the agronomic data, biochemical aspects related to quality parameters and at the molecular level using SSR markers for clustering procedure making dendrogram that helps the more accurate selection of the superior basmati genotypes for the further studies of the breeders and researchers

Effects of different plant growth regulators on in vitro callus induction in physic nut (Jatropha curcus L.)

Jatropha (Jatropha curcas L.) is an oil bearing crop growing in tropical and subtropical parts of the world. The present study was undertaken to investigate the effects of different plant growth regulators on in vitro callus induction in physic nut (J. curcus). In the present study, it was observed that all the explants viz., leaf lamina, petioles, nodal segments and cotyledonary nodes showed good callus induction responses on various culture media thus tried. Leaf lamina and petioles showed 100.0% callus induction responses on different MS media supplemented with auxins and cytokinins alone or in combinations whereas, nodal segments and cotyledonary nodes showed maximum 89.6% and 83.9% callus induction respectively. The presence of 2, 4-D in culture media with auxins or cytokinins was essential for good callus growth. Among different explants tried, leaf lamina was the best responding explants and MS-13 media supplemented with 5×10-6 M NAA and 10-5 M 2, 4-D is the best callusing and growth supporting medium. However, the regenerative competence of the callus tissues can differ depending on the type of explants used because certain types of plant tissues have more favorable regeneration responses than others. Callus induction rate from all explant types was highest than other reports. The results obtained in the present study would facilitate the high callus induction and regeneration responses in J. curcus for its improvement using biotechnological tools

The International Collaboration for Research methods Development in Oncology (CReDO) workshops: shaping the future of global oncology research

Low-income and middle-income countries (LMICs) have a disproportionately high burden of cancer and cancer mortality. The unique barriers to optimum cancer care in these regions necessitate context-specific research. The conduct of research in LMICs has several challenges, not least of which is a paucity of formal training in research methods. Building capacity by training early career researchers is essential to improve research output and cancer outcomes in LMICs. The International Collaboration for Research methods Development in Oncology (CReDO) workshop is an initiative by the Tata Memorial Centre and the National Cancer Grid of India to address gaps in research training and increase capacity in oncology research. Since 2015, there have been five CReDO workshops, which have trained more than 250 oncologists from India and other countries in clinical research methods and protocol development. Participants from all oncology and allied fields were represented at these workshops. Protocols developed included clinical trials, comparative effectiveness studies, health services research, and observational studies, and many of these protocols were particularly relevant to cancer management in LMICs. A follow-up of these participants in 2020 elicited an 88% response rate and showed that 42% of participants had made progress with their CReDO protocols, and 73% had initiated other research protocols and published papers. In this Policy Review, we describe the challenges to research in LMICs, as well as the evolution, structure, and impact of CReDO and other similar workshops on global oncology research