Effect of soil ph on postharvest pathological deterioration of sweet potato storage roots
Date
2008Author
Kihurani, A. W
Narla, R.D
Shibairo, Solomon I
Type
ArticleLanguage
enMetadata
Show full item recordAbstract
Sweet potato (Ipomoea batatas (L.) Lam.) is the world's seventh most
important food crop but its potential to contribute to food security and
income generation is limited in tropical developing countries by its short
shelf-life. Environmental and cultural stresses during growth and storage are
known to directly or indirectly predispose sweet potato storage roots to
postharvest microbial infection. Research was conducted to determine the
effect of storage temsoil pH on postharvest deterioration of sweet potato
roots using two sweet potato cultivars, Yanshu 1 (Cll' 440024) and KSP 20
(Clf 440170), and three soil pH levels, 4.6, 5.8 and 6.1 arranged in
randomized complete block design with four replications. Preharvest
experiments were conducted in a greenhouse followed by postharvest
evaluations in the laboratory at the National Agricultural Research
Laboratories (NARL), Nairobi. Nine-mm circular agar plugs, removed from
the edge of actively growing two-day old culture of two postharvest
pathogens of sweet potato, Rhizopus oryzae and Botryodiplodia theobromae.
were used to inoculate the sweet potato roots. Pathological deterioration (PD)
was estimated by measuring the diameter and depth of the developing
internal lesion (extent of tissue degradation) on the storage roots, 24 hours
after inoculation. Results showed that postharvest PD of the storage roots
was not significantly (P>0.05) influenced by growing sweet potato in soil at
the different pH levels. Growing sweet potato in soil at pH levels within the
range for normal plant growth is unlikely to affect postharvest deterioration
of the storage roots.
Key words: Ipomoea batatas, Botryodiplodia theobromae, Rhizopus oryzae
URI
http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/10615http://hakenya.net/ajhs/index.php/ajhs/article/view/12/21