Africancrops Breeding

In an effort to decrease yield losses due to foliar diseases of maize among small-scale farmers in Malawi, sixty-six (66) improved maize varieties were screened and evaluated for disease resistance and yield potential. In 1998/99 season, nine 3-way and double crosses performed very well. These nine varieties were further evaluated for gray leaf spot during 1999/2000on six sites and yield on 13 sites. Disease reaction and yield were compared with Seed Co. variety SC 627. Results showed that veriety SC 627 was highly resistant to gray leaf spot, while all other varieties showed only moderate resistance. There were significant differences (P>0.001) in severity between sites as well as severity rating (P>0.0429) between varieties. With respect to maize grain yields, varieties CZR3, CZR4, and CZR8 out-performed SC 627 under research management, while CZR3 and CZR8 were rated highly under farmer management. There was a negative correlation at Bembeke and Njolomole between yield and gray leaf spot incidence. CZR 3, CZR 4 and CZR 8 had higher percentage mphale extraction than SC 627. In 2000/2001, performance of fourteen CZR varieties was compared to MH18 and SC 627. CZR 8, CZR 4 and CZR 3 had gray leaf spot scores between 1.4 and 2.8, showing good disease resistance. The mean score for turcicum leaf blight was 2.0. CZR8, CZR4 and CZR3 performed better across sites than SC 627. Maize grain yields for CZR 8, CZR 3 and CZR 4 were higher than SC 627 under research management. These same varieties, plus SC 627, did well under farmer management. There was a negative correlation between yield and turcicum leaf blight at Makoka (r₂= -0.62) and Bvumbwe (r₂= -0.70), in the 2000/2001 season. Judging from traits such as disease reaction, texture, ear rot, husk cover, lodging and yield there is overwhelming evidence to support the release of CZR 3, CZR 4 and CZR 8, for the benefit of farmers in Malawi.