水氮耦合对马铃薯光合特性、块茎形成和品质的影响

doi:10.16420/j.issn.0513-353x.2021-0436

摘要/Abstract

摘要：

采用抗旱棚盆栽试验,以‘中薯18号’‘中薯28号’为材料,设定3种施氮与灌溉水平（低氮、中氮、高氮;水分亏缺、水分正常、水分过量）,研究不同水氮处理对株高、块茎形成、光合特性、块茎质量和品质的影响,筛选最佳水氮组合。结果表明,不同水分处理下,低氮促进了匍匐茎次顶端膨大,使块茎形成期提前,但最终未能形成高产。正常和过量水分下,两品种叶片气孔导度、净光合速率、叶绿素相对含量、株高均随着施氮量的增加而增加。同一水分处理下,地下部（地下茎和根）鲜质量、茎和叶的鲜质量均随施氮量的增加而增加。两品种在水分正常高氮处理下单株块茎质量为711.1 g、637.2 g,且此处理下两品种的净光合速率、产量水分利用效率、块茎淀粉与粗蛋白含量均达到最高水平。因此,马铃薯生育期宜采用水分正常高氮处理。

关键词: 马铃薯, 光合特性, 块茎形成, 水氮耦合

Abstract:

A pot experiment was conducted in the rain shelter to investigate the effects of irrigation regimes and nitrogen fertilizer application on the potato and develop the optimal water and nitrogen application pattern. Three irrigation regimes（insufficient irrigation amount,normal irrigation amount,excessive irrigation amount）and three nitrogen applications（insufficient nitrogen application,normal nitrogen application,excessive nitrogen application）were set in the experiment to study the effects of the potato（Zhongshu 18,Zhongshu 28）on plant height,tuber formation,photosynthetic characteristics of leaves,tuber weight and quality. The result proved that the deficient nitrogen treatment can make the subapical stolon swelled,the tuber formation period advanced,but fail to obtain high yield ultimately,in The increase of nitrogen amount made the fresh weight of underground stem,underground root,stem and leaf improved,in the irrigation treatments. The increase of nitrogen amount could raise leaf stomatal conductance,net photosynthetic rate,relative chlorophyll content and plant height,in the treatments of normal and excessive irrigation amount. In the treatment of normal irrigation amount and excessive nitrogen application,the tuber weight per plant of Zhongshu 18 and Zhongshu 28 were 711.1 g and 637.2 g;moreover,the net photosynthetic rate,the yield water use efficiency,the tuber starch and the crude protein content of both were at the highest level among all the treatments. Therefore,it is suggested that the normal irrigation amount and excessive nitrogen application should be adopted for potato growth.

Key words: potato, photosynthesis characteristic, tuber formation, water and nitrogen interaction

中图分类号:

S532

闫文渊, 秦军红, 段绍光, 徐建飞, 简银巧, 金黎平, 李广存. 水氮耦合对马铃薯光合特性、块茎形成和品质的影响[J]. 园艺学报, 2022, 49(7): 1491-1504.

YAN Wenyuan, QIN Junhong, DUAN Shaoguang, XU Jianfei, JIAN Yinqiao, JIN Liping, LI Guangcun. The Effect of Water-nitrogen Coupling on Potato Photosynthesis,Tuber Formation and Quality[J]. Acta Horticulturae Sinica, 2022, 49(7): 1491-1504.

图/表 12

参考文献 38

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处理 Treatment	水平 Level	苗期 Seedling period	块茎形成期 Tuber formation period	块茎膨大期 Tuber swelling period	淀粉积累期 Starch accumulation period
尿素/g	低 Insufficient	2.24	0	0	0
Urea	中Normal	4.67	1.33	0.67	0
	高 Excessive	7.78	2.22	1.11	0
水分/%	亏缺 Insufficient	35 ~ 45	45 ~ 55	50 ~ 60	30 ~ 40
Moisture	正常 Normal	55 ~ 65	65 ~ 75	70 ~ 80	50 ~ 60
	过量 Excessive	75 ~ 85	85 ~ 95	90 ~ 100	70 ~ 80

处理 Treatment	水平 Level	苗期 Seedling period	块茎形成期 Tuber formation period	块茎膨大期 Tuber swelling period	淀粉积累期 Starch accumulation period
尿素/g	低 Insufficient	2.24	0	0	0
Urea	中Normal	4.67	1.33	0.67	0
	高 Excessive	7.78	2.22	1.11	0
水分/%	亏缺 Insufficient	35 ~ 45	45 ~ 55	50 ~ 60	30 ~ 40
Moisture	正常 Normal	55 ~ 65	65 ~ 75	70 ~ 80	50 ~ 60
	过量 Excessive	75 ~ 85	85 ~ 95	90 ~ 100	70 ~ 80

品种 Variety	水分处理 Water treatment	氮素处理 Nitrogen treatment	单株块茎数 Number of tubers per plant	单株匍匐茎数 Number of stolons per plant	匍匐茎长度/ （cm · plant^-1） Stolon length
中薯18号 Zhongshu 18	亏缺 Insufficient irrigation	低氮Insufficient nitrogen application	2.3 ± 2.1 a	9.0 ± 4.0 a	3.7 ± 3.5 cd
		中氮Normal nitrogen application	0.0 ± 0.0 a	11.3 ± 2.1 a	3.3 ± 2.2 d
		高氮Excessive nitrogen application	0.0 ± 0.0 a	8.7 ± 3.8 a	3.6 ± 2.7 d
	正常 Normal irrigation	低氮Insufficient nitrogen application	3.0 ± 2.6 a	12.0 ± 2.0 a	5.7 ± 4.8 bc
		中氮Normal nitrogen application	0.0 ± 0.0 a	12.3 ± 6.7 a	7.7 ± 4.1 a
		高氮Excessive nitrogen application	0.0 ± 0.0 a	14.0 ± 6.0 a	5.3 ± 3.1 bcd
	过量 Excessive irrigation	低氮Insufficient nitrogen application	2.6 ± 2.3 a	14.7 ± 3.1 a	4.6 ± 3.2 bcd
		中氮Normal nitrogen application	1.7 ± 2.1 a	9.3 ± 4.7 a	6.4 ± 4.6 ab
		高氮Excessive nitrogen application	0.0 ± 0.0 a	13.7 ± 1.5 a	6.2 ± 5.5 ab
中薯28号 Zhongshu 28	亏缺 Insufficient irrigation	低氮Insufficient nitrogen application	3.3 ± 0.5 a	10.7 ± 4.7 a	4.5 ± 2.7 b
		中氮Normal nitrogen application	1.0 ± 1.7 a	5.3 ± 3.1 a	2.7 ± 1.8 b
		高氮Excessive nitrogen application	0.7 ± 1.2 a	5.3 ± 1.5 a	3.3 ± 1.9 b
	正常 Normal irrigation	低氮Insufficient nitrogen application	2.7 ± 0.6 a	9.0 ± 2.0 a	4.6 ± 2.8 b
		中氮Normal nitrogen application	0.3 ± 0.6 a	4.7 ± 0.6 a	4.5 ± 3.3 b
		高氮Excessive nitrogen application	0.0 ± 0.0 a	9.3 ± 7.1 a	3.7 ± 3.3 b
	过量 Excessive irrigation	低氮Insufficient nitrogen application	2.0 ± 1.0 a	11.3 ± 3.5 a	4.1 ± 2.9 b
		中氮Normal nitrogen application	3.0 ± 2.6 a	11.3 ± 4.5 a	6.3 ± 3.3 a
		高氮Excessive nitrogen application	2.3 ± 4.0 a	9.0 ± 5.6 a	3.7 ± 2.8 b

品种 Variety	水分处理 Water treatment	氮素处理 Nitrogen treatment	单株块茎数 Number of tubers per plant	单株匍匐茎数 Number of stolons per plant	匍匐茎长度/ （cm · plant^-1） Stolon length
中薯18号 Zhongshu 18	亏缺 Insufficient irrigation	低氮Insufficient nitrogen application	2.3 ± 2.1 a	9.0 ± 4.0 a	3.7 ± 3.5 cd
		中氮Normal nitrogen application	0.0 ± 0.0 a	11.3 ± 2.1 a	3.3 ± 2.2 d
		高氮Excessive nitrogen application	0.0 ± 0.0 a	8.7 ± 3.8 a	3.6 ± 2.7 d
	正常 Normal irrigation	低氮Insufficient nitrogen application	3.0 ± 2.6 a	12.0 ± 2.0 a	5.7 ± 4.8 bc
		中氮Normal nitrogen application	0.0 ± 0.0 a	12.3 ± 6.7 a	7.7 ± 4.1 a
		高氮Excessive nitrogen application	0.0 ± 0.0 a	14.0 ± 6.0 a	5.3 ± 3.1 bcd
	过量 Excessive irrigation	低氮Insufficient nitrogen application	2.6 ± 2.3 a	14.7 ± 3.1 a	4.6 ± 3.2 bcd
		中氮Normal nitrogen application	1.7 ± 2.1 a	9.3 ± 4.7 a	6.4 ± 4.6 ab
		高氮Excessive nitrogen application	0.0 ± 0.0 a	13.7 ± 1.5 a	6.2 ± 5.5 ab
中薯28号 Zhongshu 28	亏缺 Insufficient irrigation	低氮Insufficient nitrogen application	3.3 ± 0.5 a	10.7 ± 4.7 a	4.5 ± 2.7 b
		中氮Normal nitrogen application	1.0 ± 1.7 a	5.3 ± 3.1 a	2.7 ± 1.8 b
		高氮Excessive nitrogen application	0.7 ± 1.2 a	5.3 ± 1.5 a	3.3 ± 1.9 b
	正常 Normal irrigation	低氮Insufficient nitrogen application	2.7 ± 0.6 a	9.0 ± 2.0 a	4.6 ± 2.8 b
		中氮Normal nitrogen application	0.3 ± 0.6 a	4.7 ± 0.6 a	4.5 ± 3.3 b
		高氮Excessive nitrogen application	0.0 ± 0.0 a	9.3 ± 7.1 a	3.7 ± 3.3 b
	过量 Excessive irrigation	低氮Insufficient nitrogen application	2.0 ± 1.0 a	11.3 ± 3.5 a	4.1 ± 2.9 b
		中氮Normal nitrogen application	3.0 ± 2.6 a	11.3 ± 4.5 a	6.3 ± 3.3 a
		高氮Excessive nitrogen application	2.3 ± 4.0 a	9.0 ± 5.6 a	3.7 ± 2.8 b

品种 Variety	水分处理 Water treatment	氮素处理 Nitrogen treatment	块茎数 Number of tuber	块茎质量/g Tuber weight	产量水分利用效率/ （kg · m^-3） Yield water use efficiency
中薯18号 Zhongshu 18	亏缺 Insufficient irrigation	低氮Insufficient nitrogen application	3.8 ± 1.6 de	345.6 ± 84.7 d	13.9 ± 3.4 c
		中氮Normal nitrogen application	6.4 ± 1.5 abc	434.4 ± 70.7 c	18.0 ± 3.0 a
		高氮Excessive nitrogen application	7.0 ± 1.9 abc	456.7 ± 72.5 c	16.3 ± 2.6 ab
	正常 Normal irrigation	低氮Insufficient nitrogen application	2.8 ± 1.1 e	348.9 ± 49.1 d	10.4 ± 1.5 d
		中氮Normal nitrogen application	8.6 ± 2.1 ab	618.9 ± 38.3 b	14.5 ± 0.9 bc
		高氮Excessive nitrogen application	7.4 ± 4.1 abc	711.1 ± 116.6 a	17.2 ± 2.8 a
	过量 Excessive irrigation	低氮Insufficient nitrogen application	5.3 ± 1.4 cd	501.1 ± 103.9 c	11.0 ± 2.3 d
		中氮Normal nitrogen application	6.3 ± 2.3 bc	713.3 ± 84.0 a	14.3 ± 1.7 bc
		高氮Excessive nitrogen application	8.7 ± 1.9 a	775.6 ± 84.7 a	14.7 ± 1.6 bc
中薯28号 Zhongshu 28	亏缺 Insufficient irrigation	低氮Insufficient nitrogen application	4.2 ± 1.0 cd	335.6 ± 91.7 f	13.5 ± 3.7 a
		中氮Normal nitrogen application	6.1 ± 2.5 abc	372.3 ± 103.6 f	15.4 ± 4.3 a
		高氮Excessive nitrogen application	7.0 ± 3.0 ab	417.8 ± 158.3 ef	15.0 ± 5.7 a
	正常 Normal irrigation	低氮Insufficient nitrogen application	3.6 ± 1.1 d	490.0 ± 84.9 de	15.0 ± 2.5 a
		中氮Normal nitrogen application	4.9 ± 2.2 bcd	633.4 ± 66.9 bc	14.8 ± 1.6 a
		高氮Excessive nitrogen application	6.4 ± 3.3 abc	637.2 ± 101.7 bc	14.2 ± 3.2 a
	过量 Excessive irrigation	低氮Insufficient nitrogen application	5.2 ± 2.4 abcd	566.7 ± 89.0 cd	12.3 ± 2.0 a
		中氮Normal nitrogen application	4.1 ± 1.2 cd	730.0 ± 85.3 ab	14.6 ± 1.7 a
		高氮Excessive nitrogen application	7.4 ± 2.6 a	796.2 ± 170.4 a	14.4 ± 3.6 a