MSc

An investigation entitled “Effect of hydrogel and mulching on maize (Zea mays
L.) in sandy soil” was carried out at College of Agriculture, Padannakkad during 2016-
2018 to study the effect of hydrogel (super absorbent polymer) and mulching on soil
moisture status, growth and yield of maize in sandy soil. The experiment was laid out
in factorial randomized block design with three replications. The treatment
combinations included three levels of hydrogel viz. H1 – 1.25 kg ha-1, H2 – 2.5 kg ha-1,
H3 – 3.75 kg ha-1 and three types of mulch viz. M1 – rice straw (5 t ha-1), M2 – rice husk
(5 t ha-1), M3 – coirpith compost (2.5 t ha-1) and one control (KAU Package of Practices
recommendations). Observations were recorded on growth and growth attributes, yield
and yield attributes, plant analysis, soil analysis and economics.
Hydrogel @ 2.5 kg ha-1 and rice straw mulch @ 5 t ha-1 recorded maximum plant
height, dry matter production and root volume of maize whereas maximum leaf area and
LAI were observed in hydrogel @ 3.75 kg ha-1 and rice straw mulch @ 5 t ha-1.
The yield and yield parameters such as cob, grain and stover yield were found
to be higher in treatments receiving hydrogel @ 2.5 kg ha-1 and rice straw mulch @ 5
t ha-1 than other levels of hydrogel and types of mulch.
The response of hydrogel @ 2.5 kg ha-1 and rice straw mulch @ 5 t ha-1 was
significantly superior over other treatments with respect to total N and P uptake. While
total K uptake recorded was maximum in the case of hydrogel @ 3.75 kg ha-1 and rice
straw mulch @ 5 t ha-1.
The major beneficial effect of hydrogel was in enhancing and maintaining soil
moisture status of coarse textured sandy soil at 15 and 30 cm depth. The treatment
receiving hydrogel @ 3.75 kg ha-1 and rice straw mulch @ 5 t ha-1 recorded maximum
soil moisture retention. The maximum porosity was recorded in the case of hydrogel @
3.75 kg ha-1 and coirpith compost mulch @ 2.5 t ha-1.
The residual nutrient status with respect to available N and K2O recorded
maximum values in hydrogel @ 1.25 kg ha-1 and rice husk mulch @ 5 t ha-1 and
available P2O5 was maximum with hydrogel @ 3.75 kg ha-1 and rice husk mulch @ 5
t ha-1.
Considering the economics of maize crop production, the gross and net income
obtained were maximum in hydrogel @ 2.5 kg ha-1 and rice straw mulch @ 5 t ha-1.
However, BCR was found to be maximum in treatment with hydrogel @ 2.5 kg ha-1 and
rice husk mulch @ 5 t ha-1.
The maize growth and yield were significantly improved by the application of
hydrogel and different mulches. Hydrogel @ 2.5 kg ha-1 in combination with rice straw
mulch @ 5 t ha-1 was most efficient and economical compared to other combinations
and can be recommended for maize cultivation in sandy soils of Kerala