TY  - BOOK
AU  - Arya, C
AU  - Asha Raj, K (Guide)
TI  - Growth,green biomass production and crop interaction of selected trees and shrubs on wetland paddy bunds
U1  - 634.95  
PY  - 2023///
CY  - Vellanikkara
PB  - Department of siviculture and agroforestry, college of forestry 
KW  - Rice production
KW  - Green manuring and crop production
KW  - Gliricidia sepium (Jacq.) Walp
KW  - Paddy bunds
KW  - Agroforestry in paddy fields
KW  - Siviculture and agroforestry
N1  - MSc
N2  - Rice, the staple food in Kerala, is experiencing a significant production 
deficit, with only one-fifth of the annual requirement being met. The key to 
enhancing rice production is improving the productivity of existing agricultural 
lands. Green leaf manuring offers a promising, cost-effective, and eco-friendly 
solution to enhance productivity. Traditional green leaf manuring practices have 
been abandoned in Kerala, primarily due to the scarcity of conventional green 
leaves and various constraints, including labour and transportation. However, a 
potential approach to rejuvenate this eco-friendly practice involves cultivating 
green manuring trees and shrubs in rice bunds and maintaining them as hedges 
through regular lopping. 
This study entitled “Growth, green biomass production and crop interaction 
of selected trees and shrubs on wetland paddy bunds” was carried out as two 
separate experiments: a field experiment in State Seed Farm, Mannuthi, Thrissur; 
and Survey and documentation in Ollukkara and Wadakkanchery blocks, Thrissur, 
Kerala, during 2022-23. The study aimed to evaluate the survival, growth and 
biomass production of green manuring trees and shrubs under ill-drained conditions 
of wetland paddy bunds and their effects on paddy. The study also envisaged 
surveying and documenting the indigenous knowledge, the current practices and 
the farmer’s perspective on green leaf manuring in paddy fields of Ollukkara and 
Wadakkanchery blocks in Thrissur district.
In the first experiment, different tree species like Gliricidia, Garuga, 
Sesbania, Calliandra, Terminalia, mulberry, Gmelina, red gram and Cassia were 
planted in paddy bunds at spacing of 1m in Randomized Block Design with three 
replications. The results indicated that most species established well initially, with 
some species showing exceptional growth and biomass production. Notably, 
Sesbania (5.45 kg plant-1
), red gram (perennial) (4.10 kg plant-1
), Gliricidia (3.26 
kg plant-1
), and Terminalia (2.54 kg plant-1
) emerged as top performers in terms of 
annual biomass yield in the initial year of planting. At the same time, some species 
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had slower growth rates (Cassia and Gmelina) and lower survival rates (Garuga
and Gmelina). Garuga had only 10% survival rate, hence found unsuitable for bund 
planting in paddy. Interaction studies of trees on paddy indicate that paddy growth 
and yield were not significantly influenced by bund planting in the initial year of 
tree growth. Soil properties of paddy, like pH and nutrient content, except the 
available nitrogen content, didn’t vary across various treatments. However, a 
noticeable decline in available nitrogen content was observed in paddy soils beneath 
mulberry, indicating its competitive nature. Tree species like Sesbania, red gram, 
Cassia, Terminalia and Gliricidia, which demonstrate robust productivity and 
resilience, are excellent choices for planting on wetland paddy field bunds. When 
scaled to hectare basis, around 2 to 2.5 t/ha/year green leaf can be harvested from 
500 plants of Sesbania/red gram accommodated on bund length of 500 m/ha (bunds 
spaced at 20 m intervals in E-W direction), which can satisfy half of the 
recommended green leaf manure doses in paddy.
The study also explored local farmers’ preferences and practices regarding 
green leaf manuring. Traditionally, more than 15 tree species were utilized for green 
leaf manure, primarily collected from forests (97.5% of farmers surveyed), with 
species like Terminalia paniculata, Terminalia bellirica and Mangifera indica 
being commonly employed. However, in the present scenario, the predominant 
supplementary manures include cow dung (95%), green manure (40%), and green 
leaf manure (preferably Gliricidia sepium and Mangifera indica) (70%). These 
green leaf manures are often sourced from home gardens (62.5%) and field 
boundaries (37.5%). Farmers have recognized the adverse impacts of chemical 
fertilizers and demonstrated a strong interest in sustainable soil management. 
Despite this interest, several challenges like labour scarcity, high cost, land 
availability constraints, and transportation issues, hinder the widespread adoption 
of green leaf manuring practices. Encouragingly, approximately 80 per cent of 
farmers are interested in adopting green leaf manuring practices by planting green 
manuring trees in unused areas, boundaries, and bunds. To support this transition, 
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farmers actively seek technical support and subsidies from the Department of 
Agriculture Development and Farmer’s Welfares
ER  -