Evaluation of malting quality for early generation selection in barley

Criterion of malting quality study were 8 characteristics: seed plumpness, 1000 seed weight diastatic power, protein content, malt yield, malt extract yield and ratio of diastatic power/total nitrogen (DP/TN). The target barleys are in F4 and F5 generation of 132 lines of 17 families and in F5 and F6 generation of 28 lines of 5 families which were planted in Boon Rawd Farm (Mae Korn) of Boon Rawd Brewery Co., Ltd. in Chiang Rai and their seeds were used for malt production by micromalting technique. The result of the study was 1000 seed weight, diastatic power, protein content and DP/TN of local barley were higher than imported barley but its seed plumpness, malt yield, malt extract and malt extract yield were lower. The barley families which trend to have good malting quality was MONA/BEN//IMPALA/3/1042CA/CI9831/4/RATNA. Potentiality of barley lines studied for malting quality was observed from the one barley line having much the highest grade than standard and 11 barley lines having much higher grade by scoring. However, those barley lines had lower scores than the imported cultivar. The local barley cultivar, BRB.11 is a high standard cultivar while BRB.9 is standard cultivar and BRB.2 is under standard cultivar for malting quality. The examination of malt in the early generation found that the characters having trend to be used for screening in F4 family were seed plumpness, 1000 seed weight, diastatic power and protein content but in F5 family were seed plumpness, 1000 seed weight, diastatic power, protein, malt yield, malt extract and malt extract yield. Besides, the character to select within family was 1000 seed weight. The high genetic diversity of the study discovers that diastatic power and protein content, related to the other characteristics quite not much. Moreover, size and weight of barley connected to being high malt yield. The segregation study of barley lines showed that 1000 seed weight, diastatic power, protein content and DP/TN had higher segregation level than seed plumpness, malt yield, malt extract and malt extract yield.