Yazar "Ratnasekera, Disna" seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • [ X ]
    Öğe
    Characterization of chromosomal segment substitution lines developed in the genetic background of rice variety K 343
    (Cellular and Molecular Biology Association, 2024) Niharika; Sharma, Manmohan; Salgotra, R.K.; Sharma, Mamta; Sharma, Richa; Ratnasekera, Disna; Al-Ashkar, Ibrahim
    In this study, BC3F2 convergent population [(K343*3/RML22 × K343*3/DHMAS) × K343] was constructed by marker-assisted backcross breeding using K343 as the recurrent parent. DHMAS and RML22 were used as donor parents for the rice blast resistance genes Pi54 and Pi9, respectively. The population was first characterized using GGT 2.0 software, which showed 96.7% of the recurrent genome recovery covering 13953.6 cM, while DHMAS and RML22 showed 1.6% (235.5 cM) and 1.2% (177.1 cM) introgression respectively. The chromosomal segment substitution lines (CSSLs) were then identified using CSSL Finder software. A total of 36 CSSLs were identified, including 22 for DHMAS/K343 and 14 for RML22/K343. Introgression rates for donor substituted segments in DHMAS/K343 CSSLs ranged from 0.54% to 5.99%, with donor coverage of 44.5%, while in RML22/K343 CSSLs, introgression rates ranged from 0.54% to 4.75%, with donor coverage of 24.5%. The identified CSSLs would be a valuable genetic pool and could be used as genomic resources for the discovery and mapping of important genes and QTLs in rice genetic improvement. © 2024 Cellular and Molecular Biology Association. All rights reserved.
  • [ X ]
    Öğe
    Nitrogen Fixation of Legumes Under the Family Fabaceae: Adverse Effect of Abiotic Stresses and Mitigation Strategies
    (Springer Singapore, 2020) Sabagh, Ayman El; Hossain, Akbar; Sohidul Islam, M.; Fahad, Shah; Ratnasekera, Disna; Meena, Ram Swaroop; Wasaya, Allah
    Nitrogen (N) is an essential element of the building blocks of almost all plant structures and a vital component of chlorophyll, enzymes, and proteins. It is used in relatively large amounts than other plant nutrients. Therefore, N has been recognized as the most limiting nutrient in crop production systems. Several transformation processes are involved in the nitrogen cycle. Among them, biological nitrogen fixation is an environmentally friendly natural resource for sustainable agricultural systems. Recently, the reports directed to a decrease in agricultural dependence on symbiotic nitrogen fixation due to abiotic stresses. Therefore, abiotic stresses are a topic that increasingly occupies the attention of the world is still a matter of debate. Although physiological mechanisms are affected in more intense abiotic stresses, most research efforts have focused on the study of these processes. In legume plants being grown under symbiotic conditions, one of the primary effects of abiotic stresses is a decline in the rates of symbiotic nitrogen fixation (SNF). In the present chapter, we summarize our current understanding of the factors that are affected by SNF in legumes. Finally, an overview of the available resources and applications of the physiological system for understanding the complex responses of legumes to abiotic stresses is provided. The overall conclusion was that all physiological mechanisms are important in understanding the regulation of N2 fixation and its response to abiotic stresses. © Springer Nature Singapore Pte Ltd. 2020.
  • [ X ]
    Öğe
    Normalized Difference Vegetation Index and Chlorophyll Content for Precision Nitrogen Management in Durum Wheat Cultivars under Semi-Arid Conditions
    (Mdpi, 2021) Kizilgeci, Ferhat; Yildirim, Mehmet; Islam, Mohammad Sohidul; Ratnasekera, Disna; Iqbal, Muhammad Aamir; Sabagh, Ayman E. L.
    To impart sustainability to modern intensive farming systems, environmental pollution caused by nitrogenous fertilizers in needs to be reduced by optimizing their doses. To estimate the grain yield and nutrtional quallity of wheat, the normalized difference vegetation index (NDVI) and chlorophyll content (SPAD) are potential screening tools to identify the N deficiency and screen out the promising cultivars. The two-year field study was comprised with five levels of nitrogen (N) (control, 50, 100, 150 and 200 kg N ha(-1)) and two durum wheat genotypes (Sena and Svevo). The experimental design was split-plot, in which N levels were placed in the main plots, while wheat genotypes were arranged in sub-plots. To predict the yield and quality traits, the NDVI and SPAD values recorded at heading, anthesis and milky growth stages were taken as response variables. The results revealed that N fertilization significantly influenced the SPAD and NDVI attributed traits of durum wheat, except NDVI at milky stage (NDVI-M) during the first year. The maximum value of NDVI was recorded by 150 kg N ha(-1), while control treatment gave the minimum value. The grain yield was increased with the increasing dose of the N up to 100 kg N ha(-1) (4121 kg ha(-1)), and thereafter, it was declined with further increased of N levels. However, the variation between the genotypes was not significant, except NDVI and SPAD values at the milky stage. The genotype Svevo had the highest NDVI values at all growth stages, while the genotype Sena recorded the maximum SPAD values during both years. Similarly, the N levels significantly influenced the quality traits (protein, wet gluten, starch test weight and Zeleny sedimentation) of both genotypes. The highly significant relationship of SPAD and NDVI with the grain yield and yield attributes showed their reliability as indicators for determining the N deficiency and selection of superior wheat genotypes for ensuring food security under climate change scenario.