| dc.description.abstract | African clovers have been extensively studied for their agronomic potential in the highlands
of eastern Africa. Major adaptation to cultivation has been established to be primarily soil
moisture and fertility. Since soil moisture is a function of water availability and the
retention capacity of soils, further studies on these facets could be used to constitute an
agronomic package to allow for successful cultivation of these clovers.
The main objective of this study was to evaluate the effect of
a) Pot wetting event days per month and
b) Selected soil classes.
The study was conducted in a glasshouse using four Kenyan soils (Nitosol, Acrisol,
Andosol and Luvisol) on which were planted four African Trifolillm species namely I.
reuppellianum, I. steudneri, I.. tembense and I. qllartinanillm and were maintained under
four different wetting events: (1) 10 random pot wetting event days PWD-l O.
(2)15 random pot wetting event dayse PWD-15.
(3) 20 random pot wetting event days PWD-20.
and( 4) Continuously throughout a month PWD-30.
Data obtained indicated that at PWD-30 I. quartinanium, I. stelldneri and I.
meppeJJianllm were highest in plant height during the growing period.The highest dry
matter accumulation occurred in the high moisture treatment on Andosol. One species
(I. quartinanium) was superior to the other three in biomass production, over all soil and
pot wetting treatments. Two species (T. meppeJJianllm and I. stelldneri) were intermediate
in performance, and I. tembense showed low productivity over all treatments.
The production of seed was significantly (Ps.O.Ol) higher by I. stelldneri under high PWD-
30 moisture treatment on Andosol. The poorest seed yield occurred by I. meppeJJianllm
and I. qllartinanillm on Acrisol 10 days per month of pot wetting. There were highly
significant differences (P s 0.001) in days of flowering. I. meppeJJianllm flowered earlier
than the other three species at 10 days per month of pot wetting. At high PWD-30 moisture
treatment ,hemicellulose increased in I. quaninanium. The highest hemicellulose content
was around 12%, a mean figure higher .than the 9% reported in alfalfa. Among the pot
wetting treatments, the PWD-15 was consistently the best over the PWD-I0,PWD-20 and
PWD-30 for the performance of the clovers. This was probably due to its better intermittent
drying in between potting wetting intervals compared to continuous (PWD-30) which might
have enhanced the amount of nutrient release (e.g. N and others).
The results further confirm those of the previous studies that among the annual clovers
identified from a wide spectrum of the African clovers as being promising hay fodders,
Trifoljum quartjnanjum was the most superior in dry matter yields when grown under
ambient watering and on appropriate soil type.I. quartjnanjum performed best 15 pot
wetting days in each month of growth season than under continuous pot wetting.During a
growing season in parts of Eastern African highlands, it is close to the norm of the rainy
days in a monthof a growing season.
I. quartjnanjum when pot wetted for 15 random days in any month during its growth further
performed best in dry matter yields on Andosols which are the most predominant soils of
the highlands region. However, I. quartjnanjum had the lowest seed yields which suggest
that a further improvement or research is needed on seed yield so that this aspect can be
included in an agronomic package for cultivation of I. quartinaninm.It can be concluded
that soil types and pot wetting events 'with intermittent drying probably affected clover
growth and yield via the rate of soil nutrient release and availability. Continuous pot wetting
was thus not beneficial. | en |
