Abstract:
The present study comprising of laboratory, greenhouse and field
experiments was undertaken at plant pathology laboratory Plant Protection
Directorate and Medicinal and Aromatic Plant Research Experimental Area
(2005 – 2007), with the objectives of:
i)
Effects of extract from selected medicinal and aromatic plants on
colony growth of the inciting pathogens.
ii)
Identify the most effective plant residues on disease incidence
under field conditions.
iii)
Determine the effects of the residues on the grain yield of two
broad bean cultivars, viz Hudeiba– 72 and Hudeiba– 93.
Extracts from, Neem (Azadirachta indica L.) leaves, Argel
(Solanostermma argel L.), Fennel (Foeniculum vulgari L.), Basil (Ocimum
gratissimum L.), Lemongrass (Cymbopogon citratus L.), Vincarosea
(Catharanthus roseus L.) leaves and roots, at 5%, 10% and 7% combined
solution, were tested for their antifungal properties against Fusarium.
Oxysporum f. sp. fabae, Fusarium. Solani f. sp. fabae, (main c/o of wilt and
root rot of braod bean crop), Fusarium moniliforme, Fusarium equesiti and
Macrophomina phaseolina L. by poisoned food techniques in vitro at 25 ±
2°C. In general most of the extracts and essential oils used except those of
Vincarosea successfully inhibited colony growth. In green house
experiment, the incidence and mortality of the host were greatly reduced by
the application of the six plants residues to earthen pots (30cm i.d.) filled
with two kind of soils (natural and sterilized) for both broad bean cultivars
iv
(H. 72 & H. 93), with best control in case of the sterilized soil along with V 1
(H. 72) as compare to the control. On the other hand all the residues
incorporated into soil generally reduced the disease incidence. The
maximum reduction in disease incidence was obtained when Argel, Funnel
and Fungicide metalaxyl (Ridomil) were applied separately to the soil in
both cultivars (Hudaiba 93 & Hudaiba 72) in the two seasons.
The greatest increase in grain yield was obtained in soils supplied
with Argel, Fennel, Basil, and Lemongrass residues. Maximum yield of 2.70
kg/plot (3.5 × 4َm) was obtained when Argel residue was used.
