Growth and yield response of lettuce to different nutrient sources and organic mulches
Abstract
Lettuce is becoming popular in Uganda day by day, but its average yield is very low
compared to yields obtained in other countries in the world. The study aimed to
determine the growth and yield response of lettuce to different nutrient sources and mulching.
A field experiment with two levels of soil amendment treatment (NPK and BSLW compost)
and two levels of mulching (mulch and no mulch) were conducted to find out the effect of
nutrient source and mulching on the growth and yield of lettuce. The combined effect of
nutrient source and mulching resulted in significant variations in all the parameters that were
measured (plant height, number of leaves per plant, leaf length, leaf breadth and fresh weight
of leaves), at all the stages of growth (30, 45 and 60 DAT) and in both the mulched and un mulched treatments. Mulched plants generally performed better in almost all the parameters
that were measured than un-mulched plants. For both the un-mulched and mulched treatments,
plant height gradually increased as the application levels of both NPK and BSLW compost
increased, and similar trends were observed in the rest of the parameters measured. Based on
the overall treatment means, the leaf lengths of plants in both the mulched and un-mulched
treatments significantly (P<0.05) increased as the treatment levels of both BSLW and NPK
increased. It can be concluded that the application of mulch and compost at the rate of 33 t/ha
results in higher numbers of leaves per plant, leaf length, leaf breadth and consequently
higher fresh weight of leaves at harvest. Based on the conclusions, it was recommended that
lettuce growers should adopt mulching and 33 t/ha of BSLW compost to optimize
the yield of lettuce leaves. In addition, further studies should be carried out in different agro-ecological zones of Uganda to determine their suitability for lettuce production