English - McKnight Foundation Collaborative Crop Research Program

McKnight Foundation Collaborative Crops Research Project No: 06-741
Poor resistance to A. vogelii. Well liked by farmers.
54 Farmers’ local Collected from around trial sites, usually bushy and long maturing.
1.2 Screening for Alectra resistance.
The sites at Ngwangwa and Kasungu had high infestation of Alectra, even though yields were good..
However, within the plots, spots that had high numbers of Alectra were causing stunted growth and
wilting on cowpea plants. Observations on Alectra resistance showed that in sites with high pressure, all
entries succumbed to the parasite, though differentilly. In lightly infested sites, some entries showed
resistance (Table 3). .At Mngwangwa, where pressure was high, the same lines showed fair resistance.
At Lisasadzi, with high Alectra pressure, entries IT97K-825-15 and IT99K-494-6 showed good
resistance. At Bunda College, with high Alectra pressure, the same three lines showed resistance. On the
overall, entry 21 (IT99K-494-6) and entry 9 (IT99K-7-21-2-2-1) were best for resistance with 0.28 and
0.29Alectra plants m -2 respectively, and entry 21 having zero Alectra count at Bunda. Depending on
yield and other results, one of these three could be released. However, all these have longer maturity
periods.
As these observations were done in presence of local extension and farmers, this gave a good
opportunity to orient farmers to the Alectra problem and the objectives of the project. Since the entries
in the trial were combination of early and late maturing types, the general farmers preference at all sites
was for the early types IT82E-16 and Sudan 1. At Kasungu farmers particularly noted that IT97K-825-
15 was undesired due to its late maturity, as it would need more rains. Some of the other reasons for
preferences were grain size (large size preferred).
Table 3 Alectra counts m -2 taken after flowering at all the trial sites
Entrycode
name
& Bunda Lisasadzi Ngwangwa Mpokwa Rivirivi Chitedze Mean
5=IT98K-503-1 1.35 0.50 3.33 0.6 0.0 0.05 0.97
37=IT97K-825-
15
0.08 0.70 0.60 0.03 0.08 0.25 0.29
9=IT99K-7-21-2-
2-1
0.25 1.38 1.46 0.11 0.0 0.17 0.56
21=IT99K-494-6 0.00 0.60 1.02 0.04 0.03 0.0 0.28
53=Sudan-1 5.82 3.56 4.03 0.86 0.0 0.58 2.48
52=IT82E-16 6.25 6.70 2.86 0.96 0.14 0.0 2.82
54=Farmers’
local
2.80 1.14 3.29 - 0.03 0.11 1.23
Mean 2.36 2.08 2.43 0.44 0.04 0.17 1.25
P