Book review on “Aeromycology over Kachai lemon plantation in eastern Himalayan region”

    30-Aug-2022
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BN Pande
Contd from prev issue
SECTION WISE COMMENTS: In orders to understand the fungal components of airspora in relation to the concentration of spore loads and their relevance weather conditions with special emphasis on spore types and their correlation with disease incidence, were carried out over Kachai lemon plantation field in Ukhrul district, Manipur by using petri plate exposure method and Rotorod air sampler (Plate no. III(a) and Plate no III (b).
 Analysis of the airspora over the lemon plantation field was carried out by Prof. N.I. Singh et al for three years employed Tilak rotorod air  sampler and Petri plate exposure methods and recorded important pathogenic fungal spore types like Fusarium, Penicillium etc. and worked out on their correlation with their disease incidence.
SECTION – II: This section of the book included an important part of the work and that is “Assessment of Fungal Disease Incidence and Identification of Pathogenic Fungi Associated with Aerial Parts of Kachai Lemon. Author gave more emphasis on Assessment of Fungal Diseases with Aerial Plant Parts of Kachai Lemon. They also focused their attention on incidence and Identification of pathogens to these diseases during the survey study with Aerial Plant Parts of Kachai Lemon (Citrus jambhiri Lush). Authors isolated three fungi species from the diseased plant parts of Kachai lemon. Pathogenicity tests showed isolated organisms pathogenic since they were re-inoculated. Fusarium semitectum, Phytophthora parasitica and Penicillium digitatum. Authors have meticulously observed and reported prevalence of all the lemon orchards surveyed at different levels of infection initiated by fungi. Fusarium semitectum, Phytophthora parasitica and Penicillium digitatum.
The highest mean concentration of disease the authors recorded during 2016 with 19.67%. During these studies the authors recorded three pathogenic fungi of Kachai lemon identified as Fusarium semitectum Berk. And Ravenel, Phytophthora parasitica Dus. and Penicillium digitatum Sacc. Causing leaf wilt, gummosis, and fruit rot of lemon trees.
SECTION –III: This section author incorporated the chapter III – influence of airborne microorganisms on pollination and fertilization in Kachai lemon. The findings in summary form in this chapter as: histological studies on the stigmas of Kachai lemon indicate the possibility of the stigmatic surfaces being impacted upon by the airspora (Table 3.3.1).
Isolation of fungi from the pistils of Kachai lemon flower showed a high percentage of fungal invasion on stigma and style and it showed Fusarium sporotrichioides dominant species forming 30.95% of the total fungi taken from the stigmatic surface. Culture filtrate of Fusarium sporotrichioides inhibited pollen germination and growth of the pollen tube of Kachai lemon (Plate X a-d).
SECTION – IV: This section chapter 4th Management of fungal diseases of Kachai lemons through Phyto extracts and fungicides. In vitro evaluation on effect of different Phyto extracts on the radial growth of the Penicillium digitatum. (Table 4-4-,3 to 6: in book volume).
The summary of the study of section as under:
- Phyto extract of 10 medicinal plants showed different inhibitory effects on the three fungal pathogens of Kachai lemon.
- Phyto extracts of Curcuma longa showed highest antifungal activity against Fusarium sp. of Fusarium semitectum followed by Ageratumconyzoide and Zingiber officinale, respectively.
- Phytoextract of Curcuma longa showed maximum growth inhibition rate (%) on Phytophthora parasitica followed by Zingibr officinale, Tagetapetula and Centella asiatica respectively.
- The highest antifungal activity against Penicillium digitatum was exhibited by Azadirachta indica.
- The phytoextract used in these experiments showed maximum growth infection at high concentrations.
- Among the four fungicides tested against Penicillium digitatum, Carbendazim 50% W.P. and Thiophanate Methyl 70% showed 100% inhibition in all the concentrations (0.05%), and 0.1%).
- Carbendazim controlled 85.59% growth rate of Phytophthora parasitica at the 0.1% concentration
- Under pot experiment, reduction in the incidences and severity of the wilt disease was observed in plants treated with the phytoextract and fungicides two days before inoculation with F. semitectum suggesting the extract would be more effective when applied as opposed to curatively.
- The study on socio economic upliftment of Kachai village revealed important constraints perceived by the lemon growers, marketing constraints due to poor road condition, high fluctuation in market price, lack of technical knowledge and high morbidity of plant during initial stages. To be contd