TY  - BOOK
AU  - B Sangeetha Lakshmi
AU  - Chitra N (Guide)
TI  - Air Layering in selected fruit crops influenced by medium fortified with root colonizing fungi
U1  - 660.62 
PY  - 2023///
CY  - Vellayani
PB  - Department of Agricultural Microbiology, College of Agriculture
KW  - Agricultural Microbiology
N1  - MSc
N2  - The study entitled “Air layering in selected fruit crops influenced by medium 
fortified with root colonizing fungi” was conducted at the Department of Agricultural 
Microbiology, College of Agriculture, Vellayani during the period 2020-2022. The 
objective of the study was to investigate the effectiveness of air layering medium fortified 
with Piriformospora indica and/or Glomus fasciculatum on rooting and the establishment 
of layers of selected fruit crops.
An initial experiment was conducted to evaluate the survival of the root colonizing 
fungi in air layering medium. The tomato seedlings planted in this medium showed root 
colonization with Piriformospora indica and/or Glomus fasciculatum showed 
colonization at 4 and 6 weeks after planting confirming that the fungi survive in the 
medium. Significant increase in IAA production was observed in tomato seedlings grown 
in layering medium individually inoculated with AMF and P. indica.
Fruit crops viz., Guava, West Indian Cherry and Rambutan having varying 
percentage of rooting and establishment on air layering were selected for the study. The 
air layering medium fortified with Piriformospora indica (1% w/v), Glomus fasciculatum
(5% w/v), combination of Piriformospora indica and Glomus fasciculatum, and IBA
(1000 ppm) were used along with a control. Air-layering experiment with different 
treatments in Guava showed significantly higher root fresh weight and dry weight in 
combined inoculation of AMF and P. indica which was comparable to IBA treatment. On 
propagation of successful layer in polybags it was noted that the root volume of guava 
plants raised in laying medium fortified with P. indica, IBA and AMF (20.2,19.6 and 
17.28 cm3
, respectively) were statistically on par and significantly higher compared to 
other treatments. Guava plants grown in air layering medium fortified with P. indica 
recorded the highest root fresh weight and dry weight (7.726 g and 2.49 g respectively). 
On observation of root colonization of fungi, it was seen that P. indica colonized only in 
the inoculated plants and but native AMF was found to colonize all guava plants.
In similar studies in West Indian Cherry, layers grown in G. fasciculatum fortified 
medium recorded the highest number of primary roots, root volume (0.42 cm3
), root fresh 
weight (0.406 g) and root dry weight (0.04 g). Treatment with IBA was on par with AMF 
treatment in the number of roots and root fresh weight. The percentage of successful 
layers was significantly high in the treatment combination of P. indica and AMF (86 
percent).
In in vivo study on establishment of rooted layers of West Indian Cherry planted 
in polybags, shoot length (67.4 cm), root length (51.2 cm), root volume (25.6 cm3
), shoot 
fresh weight (27.666 g), dry weight (17.326 g), root fresh weight (8.26 g) and dry weight 
(3.956 g) were significantly higher in plants grown in air layering medium fortified with 
P. indica when compared to control. As in the case of Guava plants, West Indian Cherry 
also showed colonization by native AMF even in control plants but P. indica colonization
was observed only in P. indica inoculated plants.
The same sets of experiments in Rambutan revealed induction of callus formation 
in the wounded region two months after layering and rooting three months after air 
layering in medium fortified with P. indica and G. fasciculatum. Even though there was 
rooting, the number of successful layers were less and those rooted layers, when planted 
in the polybags for further study, dried off.
Results of the present study suggest that fortification of air layering medium with 
root colonizing fungi viz., Piriformospora indica and Glomus fasciculatum can improve 
rooting and establishment of layers in Guava and West Indian cherry and the results are 
comparable to that of IBA treatment at 1000 ppm
ER  -