Person:
Joshi, A.K.

Profile Picture
Email Address
Birth Date
Research Projects
Organizational Units
Job Title
Last Name
Joshi
First Name
A.K.
Name
Joshi, A.K.
ORCID ID
0000-0003-4205-9329

Filters

2002 - 200912010 - 20123
Reset filters

Settings

Region: Global × AGROVOC: COCHLIOBOLUS SATIVUS ×

Search Results

Now showing 1 - 4 of 4
  • Thumbnail Image
    Technique for the maintenance of heterokayotic isolates of Bipolaris sorokiniana under ordinary conditions
    (Springer, 2012) Chand, R.; Yadav, O.P.; Bashyal, B.M.; Prasad, L.C.; Joshi, A.K.
    One hundred heterokaryotic isolates of Bipolaris sorokiniana, collected from wheat during 1997-1998, were evaluated for their morphology, growth, number of nuclei/cell and disease causing ability. Autoclaved sorghum grains were used to colonize
    Publication
  • Thumbnail Image
    Bipolaris sorokiniana of barley: infection behaviour in different members of Poaceae
    (Springer, 2011) Bashyal, B.M.; Chand, R.; Kushwaha, C.; Joshi, A.K.; Kumar, S.
    Host range and infection behaviour of Bipolaris sorokiniana of barley was studied in wheat, barley, rice, phalaris, maize, pearlmillet and sugarcane. B. sorokiniana of barley varied in percent germination, germination behaviour, germ tube length and number of appressoria formation in different hosts. Growth of pathogen was arrested at appressoria formation stage in sugarcane and it could not infect the host. Further accumulation of less cell wall bound phenolics (4-hydroxybenzoic acid, vanillic acid, 4-hydroxybenzaldehyde, vanillin and 4-coumaric acid) and phenylalanine ammonia lyase (PAL) in barley and wheat indicated the role of these compounds in conferring resistance against B. sorokiniana of barle
    Publication
  • Thumbnail Image
    Diversity and association of isolates and symptoms of spot blotch caused by Bipolaris sorokiniana of barley (Hordeum vulgare L.)
    (Springer, 2010) Chand, R.; Pradhan, P.K.; Prasad, L.C.; Kumar, D.; Verma, R.P.S.; Singh, D.P.; Joshi, A.K.
    A three year (2003-2005) survey was conducted to study the occurrence of spot blotch symptoms on barley genotypes grown in the eastern Gangetic plains of India. Nine types of symptoms were recorded. The two most prevalent symptoms were - oval to elongate surrounded by yellow margin (type A) and, narrow, elongated dark brown spots (type D). It was also observed that symptom type D changed to type A after a week from its appearance. The pathogen Bipolaris sorokiniana isolated from these symptom types were categorized in to four pathogenic groups viz., 1, 2, 3, and 5. These pathogenic groups were distributed among all symptom types. However, groups 1 and 5 were the most common and comprised of around 74% of the total spot blotch pathogen population recovered from all symptom types.
    Publication
  • Thumbnail Image
    Physiological and morphological aspects of bipolaris sorokiniana conidia surviving on wheat straw
    (Korean Society of Plant Pathology, 2002) Chand, R.; Singh, H.V.; Joshi, A.K.; Duveiller, E.
    Wheat samples showing typical spot blotch symptoms on stems and sheaths were collected from the field after physiological maturity, and were sealed in paper bags and stored in the laboratory at room temperature to study the survival of Bipolaris sorokiniana conidia on wheat straw. The materials were observed at monthly intervals to assess the conidia viability during storage. After 4 months, the frequency of individual conidia already present on wheat straw at the time of sampling was reduced and appeared to be progressively replaced by the formation of round structures consist-ing of conidia aggregates. After 5 months, distinct, individual conidia were no longer detected, and only 'clumps of conidia' were observed. These dark black aggregates or 'clumps of conidia’measured 157-170 μm in diameter and were grouped into boat-shaped olivacious conidia showing thick wall and measuring 50-82 × 20-30 μm. The germination was unipolar and below 0.5%, suggesting the occurrence of dormancy, In contrast, individual conidium produced on wheat during the growing season were 96-130 × 16-20 μm, slightly curved, hyaline to light pale, and euseptate with a bipolar germination reaching 98-100%. Bipolaris sorokiniana conidia produced on PDA were 55-82 × 20-27 μm, tapered at both ends, dark brown to olivacious, distoseptate, showed up to 1% germination, and were predominantly unipolar. Results of the present study suggest that B. sorokiniana conidia belonged to two different physiological categories corresponding to the pathogen's infection phase and its survival, respectively. The infection phase is characterized by a high germination percentage as opposed to the survival phase harboring apparent dormancy
    Publication