施氮水平对不同淀粉型马铃薯块茎产量和淀粉品质的影响

Effects of nitrogen fertilizer application rate on the tuber yield and starch quality of potato varieties with different starch contents

为研究施氮水平对不同淀粉型马铃薯块茎产量、淀粉产量和品质的影响,选用生育期相近的高淀粉品种‘克新22号’和低淀粉品种‘克新19号’为试验材料,施氮量设0、75、150、225和300kg/hm^2共5种处理,在收获后,分别测定马铃薯的块茎产量、淀粉含量、淀粉产量和淀粉直支比,探讨施氮水平对这些性状的影响规律。施氮量在0～300kg/hm^2时,‘克新22号’品种的块茎产量随着施氮量的增加呈单峰曲线变化,其中,施氮量在225kg/hm^2时,块茎产量最高;而‘克新19号’品种的块茎产量则呈持续增加的趋势。2个品种块茎干重中直链淀粉、支链淀粉及总淀粉含量均随着施氮量的增加而呈降低变化;而块茎鲜重中直链淀粉、支链淀粉及总淀粉含量随着施氮量的增加则呈先增后降的单峰曲线变化;施氮量在75kg/hm^2时,块茎鲜重中直链淀粉、支链淀粉及总淀粉含量达到最高。2个品种的淀粉直支比均随着施氮量的增加呈降低的变化趋势。‘克新22号’品种的块茎直链淀粉、支链淀粉及总淀粉产量随着施氮量的增加均呈先增加后降低的单峰曲线变化;施氮量在150kg/hm^2时获得较高的直链淀粉、支链淀粉和总淀粉产量。‘克新19号’品种的块茎直链淀粉产量随着施氮量的增加一直呈持续增加的变化,而块茎的支链淀粉及总淀粉产量则呈先增加后降低的单峰曲线变化;施氮量225kg/hm^2时获得较高的支链淀粉和总淀粉产量。

In order to study the effects of nitrogen fertilizer application rate on the tuber yield,starch yield and quality of potato varieties with different starch contents,two potato varieties,high starch ‘Kexin 22’ and low starch ‘Kexin 19’ with similar growth period,were used as test materials and five nitrogen (N) fertilizer application rates of 0,75,150,225,and 300 kg/hm^2 were selected in this research.After harvest,potato tuber yield,starch content,starch yield,and ratio of amylose to amylopectin were measured to analyze the effects of N fertilizer application rate on these traits.When the N fertilizer application rate was increased in the range of 0-300 kg/hm^2,tuber yield of high starch variety ‘Kexin 22’ showed a trend of first increase then decrease and the tuber yield reached the highest at 225 kg/hm^2.The tuber yield of low starch variety ‘Kexin 19’ showed a trend of continuous increase.With the increase of N fertilizer application rate,the amylose,amylopectin,and total starch contents on the dry weight basis (DW) of both varieties showed a trend of continuous decrease,while the amylose,amylopectin,and total starch contents on the fresh weight basis (FW) showed a tendency of first increase then decrease.When the N fertilizer level was at 75 kg/hm^2,the amylose,amylopectin,and total starch contents (FW) of tuber reached the highest values.In the two varieties,a continuous decreasing tendency was found for the ratios of amylose to amylopectin in starch.The yields of amylose,amylopectin,and total starch of high starch variety ‘Kexin 22’ showed a trend of first increase then decrease with the increase in N fertilizer application rate.When N application rate was at 150 kg/hm^2,the yields of amylose,amylopectin,and total starch were highest.The yield of amylose of low starch variety ‘Kexin 19’ showed a trend of continuous increase,while the yields of amylopectin and total starch showed a trend of first increase then decrease with the high values appearing at 225 kg/hm^2 of N fertilizer application rate.