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A. B. Malannavar ¹, D. K. Banyal ¹

Affiliations
1 Department of Plant Pathology, CSK Himachal Pradesh Krishi Vishvavidyalaya, Palampur-176 062, IN

Abstract

Powdery mildew of oat (Blumeria graminis f. sp. avenae) is the most deleterious foliar disease of cultivated oat, particularly in cooler regions. Slow mildewing, a partial resistance behaves genetically as a quantitative trait and can be assessed by comparing with mildew development on a highly susceptible cultivar grown under the same conditions. The slow mildewing components (disease severity, AUDPC and infection rate) under field conditions were studied in 15 moderately susceptible along with highly susceptible check (HJ-8) selected from panel of 303 field screened oat genotypes. The lines were categorized into slow mildewing categories based on terminal disease severity and AUDPC values. The AUDPC values of these lines ranged from 475 (JPO-45) to 1775 (HJ-8) and infection rate ranged from 0.053 to 0.144, being minimum in JPO-45 and maximum in HJ-8. All the tested lines gave 3 or 4 infection type under greenhouse evaluation and were designated as moderately susceptible and susceptible genotypes. Three oat lines showing moderately susceptible reactions, along with HJ-8 were selected to carry out experiment on slow mildewing in greenhouse. Among all the selected lines, the incubation period varied between 3-4 days and latent period between 4-5 days, i.e. maximum of 4 and 5 days, as compared to minimum of 3 and 4 days in HJ-8, respectively. After 11 days of inoculation, countless conidiophores bearing conidia were produced on all the lines except in IG-03-203. The size of powdery mildew colony was recorded and maximum colony size 3.87 mm was observed in HJ-8 followed by 2.87, 3.37 and 3.30 mm in IG-03-203, JPO-20 and KRR-AK-06, respectively.

Keywords

Oat, Powdery Mildew, Area Under Disease Progress Curve (AUDPC), Infection Rate, Slow Mildewing.

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Shiney Chatak ¹, D. K. Banyal ¹

Affiliations
1 Department of Plant Pathology, CSK Himachal Pradesh Krishi Vishvavidyalaya, Palampur-176 062, IN

Abstract

Urdbean (Vigna mungo L. Hepper) also known as mash or blackgram is important Kharif pulse.It suffers from many diseases in which anthracnose leaf spot caused by Colletotrichum truncatum (Schwein) Andrus and Moore occur in endemic form in high rainfall areas and result in qualitative and quantitative yield losses. The field experiments on integrated management of anthracnose revealed that among organic and natural inputs, three sprays of panchgavya (@10%) at ten days interval gave maximum disease control of 33.64 per cent with 26.14 per cent yield increase whereas crude extract of botanicals i.e. Melia azedarach (Darek), Eucalyptus sp. (eucalyptus), Eupatorium odoratum (Basuti) and Lantana camera (lantana) three foliar sprays of eucalyptus (@30%) at 10 days interval gave maximum disease control of 28.18 per cent with 21.62 per cent increase in yield. The seed treatment with bioagents viz; Trichoderma koningii (DMA-8), Trichoderma koningii (JMA-11), Trichoderma harzianum (SMA-5), Trichoderma harzianum (TH-11) and Trichoderma viride was less effective and gave only 4.88 to 10.98 disease control with 2.79 to 6.04 per cent yield increase. all the five fungicides viz; mancozeb 75WP, carbendazim 50WP, propiconazole 25EC, tebuconazole 25EC and trifloxystrobin 25% + tebuconazole 50% were found effective and gave 42.58 to 77.99 per cent disease control with 33.12 to 43.18 per cent yield increase over check.

Keywords

Urdbean, Anthracnose, Colletotrichum truncatum, IDM Components.

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