NOPR Collection: Pages 293-360

Influence of temperature on symptom expression, detection of host factors in virus infected Piper nigrum L.

2016-05-01T00:00:00Z

Title: Influence of temperature on symptom expression, detection of host factors in virus infected Piper nigrum L. Authors: Umadevi, P; Bhat, AI; Krishnamurthy, KS; Anandaraj, M Abstract: Expression of symptoms in black pepper plants (Piper nigrum) infected with Piper yellow mottle virus (PYMoV) vary depending on the season, being high during summer months. Here, we explored the influence of temperature on symptom expression in PYMoV infected P. nigrum. Our controlled environment study revealed increase in virus titer, total proteins, IAA and reducing sugars when exposed to temperature stress. There was change in the 2-D separated protein before and after exposure. The 2-D proteomics LC-MS identified host and viral proteins suggesting virus-host interaction during symptom expression. The analysis as well as detection of host biochemical compounds may help in understanding the detailed mechanisms underlying the viral replication and damage to the crop, and thereby plan management strategies. Page(s): 354-360

Improvement of banana cv. Rasthali (Silk, AAB) against Fusarium oxysporum f.sp. cubense (VCG 0124/5) through induced mutagenesis: Determination of LD₅₀ specific to mutagen, explants, toxins and in vitro and in vivo screening for Fusarium wilt resistance

2016-05-01T00:00:00Z

Title: Improvement of banana cv. Rasthali (Silk, AAB) against Fusarium oxysporum f.sp. cubense (VCG 0124/5) through induced mutagenesis: Determination of LD₅₀ specific to mutagen, explants, toxins and in vitro and in vivo screening for Fusarium wilt resistance Authors: Saraswathi, MS; Kannan, G; Uma, S; Thangavelu, R; Backiyarani, S Abstract: Shoot tips and in vitro grown proliferating buds of banana cv. Rasthali (Silk, AAB) were treated with various concentrations and durations of chemical mutagens viz., EMS, NaN₃and DES. LD₅₀ for shoot tips based on 50% reduction in fresh weight was determined as 2% for 3 h, 0.02% for 5 h and 0.15%for 5 h, while for proliferating buds, they were 0.6% for 30 min, 0.01% for 2 h and 0.06% for 2 h for the mutagens EMS, NaN₃ and DES, respectively. Subsequently, the mutated explants were screened in vitro against fusarium wilt using selection agents like fusaric acid and culture filtrate. LD₅₀ for in vitro selection agents calculated based on 50% survival of explants was 0.050 mM and 7% for fusaric acid and culture filtrate, respectively and beyond which a rapid decline in growth was observed. This was followed by pot screening which led to the identification of three putative resistant mutants with an internal disease score of 1 (corm completely clean, no vascular discolouration). The putative mutants identified in the present study have also been mass multiplied in vitro. Page(s): 345-353

Genetic differentiation and karyotype variation in Hedysarum chaiyrakanicum, an endemic species of Tuva Republic, Russia

2016-05-01T00:00:00Z

Title: Genetic differentiation and karyotype variation in Hedysarum chaiyrakanicum, an endemic species of Tuva Republic, Russia Authors: Zvyagina, Natalia S; Dorogina, Olga V; Krasnikov, Alexander A Abstract: Overgrazing and mining affect vegetation, particularly in mountains. At times, it goes to such an extent that the plant species become vulnerable and slowly extinct from its habitat. Such endemic species need to be protected. One such endemic species Hedysarum chaiyrakanicum Kurbatsky, a vulnerable steppe vegetation of Tuva Republic, Russia was evaluated for its genetic diversity and taxonomic definition using molecular technique and chromosome number adjustment. The genetic differentiation among H. chaiyrakanicum, H. setigerum Turcz. and H. gmelinii Ledeb. genotypes was determined using five inter-simple sequence repeat (ISSR) markers and then examined with Nei’s genetic distance coefficient (D) and Shannon’s information index (H). A total of 134 reproducible bands were detected with polymorphism percentage of 98%. The genetic diversity of H. chaiyrakanicum was found to be 0.343 while the Shannon index H_sp was determined as 8.06. The chromosome number 2n = 16 is newly observed within the H. chaiyrakanicum. The genetic relationship based on ISSR data supported the taxonomic distinction of H. chaiyrakanicum from H. setigerum and H. gmelinii. We recommend both in situ and ex situ conservation strategies, specially germplasm sampling, to save this endemic species. Page(s): 338-344

Expression analysis of bZIP transcription factor encoding genes in response to water deficit stress in rice

2016-05-01T00:00:00Z

Title: Expression analysis of bZIP transcription factor encoding genes in response to water deficit stress in rice Authors: Ali, Kishwar; Rai, RD; Tyagi, Aruna Abstract: In plants, basic region/leucine zipper motif (bZIP) transcription factors regulate several developmental processes and activate genes in response to biotic and abiotic stresses. Role of stress responsive bZIP transcription factors was studied in paddy in relation to different stages of development and water deficit stress (WDS) in a drought tolerant cultivar N22 and susceptible IR 64. Further, relative water content (RWC), membrane stability index (MSI) and abscisic acid (ABA) content were measured as indices of WDS at different stages of development and levels of stress. Expression of stress responsive bZIP transcription factors was directly correlated to developmental stage and WDS and indirectly to RWC, MSI and ABA content. Page(s): 332-337

NOPR Collection: Pages 293-360

Influence of temperature on symptom expression, detection of host factors in virus infected Piper nigrum L.

Improvement of banana cv. Rasthali (Silk, AAB) against Fusarium oxysporum f.sp. cubense (VCG 0124/5) through induced mutagenesis: Determination of LD50 specific to mutagen, explants, toxins and in vitro and in vivo screening for Fusarium wilt resistance

Genetic differentiation and karyotype variation in Hedysarum chaiyrakanicum, an endemic species of Tuva Republic, Russia

Expression analysis of bZIP transcription factor encoding genes in response to water deficit stress in rice

Improvement of banana cv. Rasthali (Silk, AAB) against Fusarium oxysporum f.sp. cubense (VCG 0124/5) through induced mutagenesis: Determination of LD₅₀ specific to mutagen, explants, toxins and in vitro and in vivo screening for Fusarium wilt resistance