Abstract
Aim:
To assess sustainable yield levels and manure and/or urea needed to sustain
in arid zone.
Methodology: A field experiment was conducted over a period of 25
years in arid soils of Jodhpur with three levels of manure (0, 2.5 and 5.0 t
ha-1 yr-1), urea (0, 20 and 40 kg N ha-1 yr-1)
and their combinations to assess the rate of change in yield of pearl millet
cultivated with manure and/or urea; minimum quantity of manure and/or urea to
be applied for achieving yield stability and minimum quantity of manure
and/or urea to be applied for improved soil biological health vis-a-vis yield
sustainability.?
Results:
Application of fertilizers over the years showed significant impact on the
status of soil organic carbon (SOC) and soil fertility, which in turn
influenced sustainability. The results showed that SOC had significant effect
on sustainable yield index (SYI). However, available soil N status did not
much influence the SYI. Application of urea-N alone or even that of 2.5 ton
manure alone is not adequate to achieve agronomic sustainability of yield.
Interpretation: Integration of FYM @ 2.5 t ha-1
yr-1 with 20kg N ha-1 sustained higher productivity to
self-effacing economic status for farmers in a fragile ecosystem with the
available minimum resources for livelihood and also sustain soil biological
health of arid soils.
Key
words:
Arid soil, Organic fertilizer, Pearl millet, Soil organic carbon
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