Farmers' seed sources and seed quality: 1. Physical and physiological quality.

摘要

Understanding farmers' seed quality problem will enable farmers to devise strategies to improve quality at the farm level. The study was conducted to assess the quality of seed used by farmers from different sources and regions. A total of 304 wheat (Trticium aestivum L. and T. durum L.) seed samples from Ethiopia and 206 wheat and 200 barley (Hordeum vulgare L.) seed samples from Syria were collected from major wheat and barley growing regions to investigate the quality of seed obtained from various sources and regions and planted by farmers. A 1 kg sample was drawn from seed lots intended for planting from each farmer. A detailed questionnaire was used to collect information on seed selection and management practices and farmers' perception of seed quality. The physical and physiological quality of seed samples was analyzed using standard testing procedures. In Ethiopia, the mean physical purity and germination of wheat seed was 98.92% and 96%, respectively, and the majority of samples (93%; n=303) met the minimum purity and germination standards for certified seed 2. Certified seed from the formal sector seed had the highest analytical purity (99.4%), but this was not significantly different from other seed sources, such as neighbors/other farmers (98.8%), local traders/markets (98.6%), or own saved seed (98.9%). However, the mean germination for certified seed (96%) showed a weak significant difference from seed obtained from other sources (94%). In Syria, mean physical purity and germination for wheat was 97.6% and 88%, respectively, and for barley 95.5% and 86%, respectively. Seed quality was better in wheat than in barley. The majority of wheat seed samples, i.e., 70.4% (n=206) for physical purity and 78.2% for germination, met the minimum seed quality requirements of certified seed 2. In barley, only 10% of samples for physical purity and 72% of samples for germination met this standard. Contamination with weed seeds appeared to be the major constraint for seed samples not meeting the standard of formal sector. There was no significant difference in physical and physiological quality of wheat seed samples obtained from different sources. In barley, germination from different sources was significantly different. Highly significant differences in seed quality were observed for seed samples collected from different regions and districts for wheat and barley crops in both countries. Vigor indices showed significant differences among wheat and barley seed samples from different regions and districts, but not among different sources. Simple correlation coefficients showed significant relationships among vigor tests. The standard germination, speed of germination, and seedling root length were well correlated with field emergence in wheat and barley in both countries. Farmers used local seed management practices, such as seed selection, cleaning, treatment, or separate storage to improve or maintain seed quality. A large number of seed samples managed differently by farmers met the minimum physical purity and germination standard for certified seed 2, producing seed comparable to those from the formal sector. It is imperative that national seed polices equally recognize the role of both formal and informal sectors and provide support to create an integrated seed system catering to the needs of a diverse group of farmers.