Management of Loon Smut and Leaf Stripe of Barley Using Seed Dressing Fungicides

Barley is one of the most important food crops in northwestern Ethiopia. Two row local barley "Semereta" is most widely grown due to its earliness as relief food supply until other crops are harvested. But yield is limited to less then 1 t/ha due to various constraints among which diseases like loose smut and stripe disease are the major factors. Disease survey conducted before revealed that incidence of loose smut and stripe disease could reach upto 28 percent and 18 percent, respectively. This study was undertaken in 1990 and 1992 at Adet to identify effective seed dressing fungicide that could reduce this threat from these diseases in an integrated disease management system. The experiment was laid out in RCB design in 3 replication using highly infected seed of "semereta" collected from farmer fields. Five fungicides, namely Vincit (flutriafol + thiabendazol), Prelude universal (Prochloraz + Carhoxin), Agroson H (phenylmercury acetate) Vitauax/prochloroz (carboxin + prochloraz) and Bayton universal (triadimenol + imazalil + fuberidazole) were tested at manufacturers recommended rates. Sixty gram of the seed was drytreated, shaked for 10 min and kept for 10, 30 and 90 days in flasks at room temperature before planting. The plots received 60/60 kg/ha N/P2O5 at sowing and observation was made on seedling height, plant height, disease incidence, 1000 grain weight and grain yield. All fungicides except Agrosan H controlled both diseases with mean control of 81.9 to 99.4 percent loose must and 94.9 to 100 percent stripe disease over the untreated seeds. Agrosson H was only effective in controlling stripe disease. All fungicides were effective at all times of seed dressing. Seedling height was not affected by all the treatment except Bayton universal treated 90 days before planting. Plant height, spike length, seed germination and 1000 seed weight were not influnced by any of the treatments. Seed dressing with Baytan univeral gave the highest yield (25 q/ha) followed by Vincit "F" (23.5 q/ha) and Prelude universal (23.1 q/ha), all treated 90 days before planting, with a yield increase of 18.5 percent, 11.6 percent and 11.2 percent over the untreated seeds, respectively.