Bananas and Food Security - Bioversity International

Asie - Pacifique / Asia - Pacific : P. Sundararaju
fertilisers, time of application, etc. vary significantly with different zones and agroclimatic
conditions. Pronounced symptoms of nutrient deficiency are exhibited in
absence of optimum level.
In field experiments, application of 25% N through 1 kg neem cake and 50% N as
inorganic source recorded sustainable production. Nematode population was
significantly reduced in plots receiving neem-cake. Response to Zn, Bo and Mn sprays
has been observed. To integrate the nutrient needs based on plant analysis has been
attempted. Leaf nutrients ranges are worked out. In sodic soils, Monthan (ABB) and
Karpuravalli (ABB) have proved to be better substitutes. Azospirillum and VAM
association has increased yield in Poovan and Ney Poovan cultivars.
Irrigation
Banana requires large quantity of water for maximum productivity. Water requirement
ranges between 1500 and 2000 mm per year. The consumptive use of water is 3-6 mm per
day, depending on cultivar and weather conditions. Nendran gave highest yield when
irrigation was given at 30 mm cumulative pan evaporation (CPE). Cavendish showed best
performance at 40 mm cumulative pan evaporation (CPE), whereas Karpuravalli gave
optimum yield at 80 mm CPE. In humid tropics with well-distributed rainfall of 25 mm
per week no supplementary irrigation is needed. Growth and initial reproductive phases
are most critical to soil moisture. Among the methods of irrigation, drip irrigation
induced earliness and improved yield as well as saved 40-45% water. Drip irrigation is
widely adopted especially in low-rainfall area. Mulching using sugarcane trash 5-6
tonnes/ha has been recommended for better production. Polythene mulch was also
found beneficial for conserving moisture.
Weed management
Losses caused by weeds in banana plantations are more than that caused by pests and
diseases. Experiments conducted in different regions suggest that weeds depending
upon cultivars and weed intensity cause 40-70% losses. The initial six months period is
critical, keeping the plots weed free as weeds compete for water, nutrients and solar
energy. Weeds also act as alternate hosts to leaf spot diseases. Survey of weeds in banana
plantations of India has revealed the occurrence of more than 30 weed species of which
Cyanodon dactylon (L) and Cyprus rotundus are predominant.
Integrated method of weed management, which include growing of cowpea, spraying
of Glyphosate/Grammaxone and hand weeding is cost effective. Regular hand weeding,
pre- and post-emergent sprays of herbicides and growing of cowpea in interspace is the
effective method to control weeds. Efficacy of weedicide is enhanced by addition of 0.5%
urea. Growing double row cowpea twice is found effective in controlling the weeds.
Bunch management
Among the several bio-regulators tried at different locations, application of 2, 4-D (10-20
ppm) improved the bunch weight especially with Kottavazhai in Poovan variety. Bunch
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