Wang De-Sen

Relationship of Mixograph parameters with Farinograph and Extensograph parameters, and bread-making quality traits.

A field experiment with 225 kg ha-1 N fertilizer application was carried out in 2006 and 2007 on the farm of Yangzhou university,Jiangsu province,China.Using 12 rice genotypes(six N-efficient and six N-inefficient) selected from 120 rice cultivars grown in Yangzhou during 2004 and 2005 to investigate the relationship among the plant-type characteristics,N use efficiency and yield performance.The results showed that the top three leaves length and drop-angle of high yield and N-efficient rice genotypes were 9.29%,65.30% lower than those of the low yield and N-inefficient ones,and the width of the top three leaves,population LAI,valid LAI,high valid LAI,and LW/LA(leaves weight/leaves area) of the former of were 29.25%,8.27%,13.32%,6.66%,and 5.82% higher than those of the latter on average respectively.The high yield and N-efficient genotypes had higher lodging resistance capability and more reasonable distribution for the length of internodes on stem than the low yield and N-inefficient ones.Yield and N use efficiency negatively correlated(significantly at P0.05 or P0.01) with the length and drop-angle of the top three leaves,while positively correlated(significantly at P0.05 or P0.01) with the width of the top three leaves,population LAI,valid LAI,high valid LAI,SLW,anti-broken strength,bender moment,and lodge index.Especially,the length and width of the flag and top 3rd leaves played an important role in the N use efficiency.It was indicated that good plant-type structure is a prerequisite for N use efficiency.Prediction of end-use quality using parameters from simple testing instruments as Mixograph is critical for efficient se- lection in breeding programs for wheat (Triticum aestivum L.) quality improvement. In this study, 241 wheat cultivars and advanced lines were sown in Beijing, Jinan, Anyang, and Zhengzhou, China from 2002 to 2009 growing seasons. The Mixograph parameters of these cultivars were measured for determining their associations with Farinograph and Extensograph parameters, and bread-making quality traits. The multiple stepwise regression analysis revealed that Farinograph stability time, Extensograph maximum resistance and energy area, and bread score could be efficiently predicted by Mixograph midline peak value, peak width, peak integral, time× value, and tail value, which accounted for 61.0-68.0% of the phenotypic variation, with the fitting degrees of 0.83 and 0.95 for the model of Farinograph stability time and Extensograph energy area, respectively. Farinograph water absorption and development time, Extensograph extensibility, and loaf volume could be predicted by Mixograph midline peak value, peak width, peak integral, right value, right integral, and time x integral, accounting for 46.0 − 55.0% of the phenotypic variance. The Midline peak integral pre- sented as the most important parameter for predicting Extensograph maximum resistance and energy area, and explained 58.7% and 59.7% of the variances, respectively. Midline peak integral and peak value were the two most important parameters when using