施氮量对饲用高粱干物质积累、分配及水分利用效率的影响  

Effect of nitrogen application rate on dry matter accumulation,allocation and water use efficiency of forage sorghum

作　　者：高玮 受娜 蒋丛泽 马仁诗 沈禹颖[1] 杨宪龙 GAO Wei;SHOU Na;JIANG Cong-ze;MA Ren-shi;SHEN Yu-ying;YANG Xian-long(State Key Laboratory of Grassland Agro-ecosystems,Key Laboratory of Grassland Livestock Industry Innovation,Ministry of Agriculture and Rural Affairs,Engineering Research Center of Grassland Industry,Ministry of Education,College of Pastoral Agriculture Science and Technology,Lanzhou University,Lanzhou 730020,China)

机构地区：[1]兰州大学草地农业生态系统国家重点实验室,兰州大学农业农村部草牧业创新重点实验室,兰州大学草地农业教育部工程研究中心,兰州大学草地农业科技学院,甘肃兰州730020

出　　处：《草业学报》2022年第9期26-35,共10页Acta Prataculturae Sinica

基　　金：国家重点研发计划课题(2021YFD1100501);甘肃省自然科学基金(21JR7RA488);国家牧草产业技术体系(CARS-34);兰州大学中央高校基本科研业务费专项资金(lzujbky-2021-14)资助。

摘　　要：为探明陇东旱塬区饲用高粱的适宜氮肥用量,于2019-2020年研究了不同施氮水平(0、80、160、240、320 kg·hm^(-2),分别用N_(0)、N_(80)、N_(160)、N_(240)、N_(320)表示)对饲用高粱‘F10’干物质积累、分配、耗水量及水分利用效率的影响。结果表明,随着施氮量的增加,饲用高粱拔节、抽穗、开花和灌浆期的干物质积累量均表现为增加趋势,至乳熟收获期,饲用高粱干物质积累量表现为先增后降的特点,其中N_(160)处理下干物质积累量最大,2019和2020年分别为22.3和18.0 t·hm^(-2)。随着生育时期的推进,饲用高粱叶片干物质分配比例逐渐降低,茎的干物质分配比例先增加后降低。乳熟收获期,茎的干物质分配比例最高,2019和2020年平均分配比例分别为70.8%和73.8%。2019年收获期,与N_(0)处理相比,施氮处理下穗的干物质分配比例显著增加,茎的干物质分配比例显著降低,但2020年整体差异不显著。2019年,不同施氮水平下饲用高粱耗水量和耗水强度均无显著差异。2020年,不同处理饲用高粱耗水量为483.4~505.8 mm,耗水强度为3.1~3.3 mm·d^(-1),其中,N_(80)和N_(320)处理下饲用高粱耗水量较N_(0)处理分别显著增加4.6%和3.9%,耗水强度较N_(0)处理均显著增加6.5%。2019和2020年,N_(160)处理下饲用高粱水分利用效率均最高,分别为42.9和36.4 kg·hm^(-2)·mm^(-1)。回归分析显示,当施氮量为166.7 kg·hm^(-2)时(接近于160.0 kg·hm^(-2)),饲用高粱收获期可获得最大干物质积累量(19.2 t·hm^(-2));当施氮量为150.0 kg·hm^(-2)时,饲用高粱可达最大水分利用效率(37.8 kg·hm^(-2)·mm^(-1))。因此,综合干物质积累与水分利用效率,初步推荐陇东旱塬区饲用高粱适宜施氮量为150~160 kg·hm^(-2)。To ascertain the appropriate N fertilizer rate for forage sorghum(Sorghum bicolor)production in dry regions of the Longdong Loess Plateau,a two-year field experiment was conducted at the Qingyang National Field Station of Grassland Agroecosystem during 2019 and 2020 to determine the effects of different N fertilizer application rates on dry matter accumulation,allocation,water consumption,and water use efficiency of forage sorghum cultivar‘F10’.Five N application rates:0,80,160,240,and 320 kg·ha^(-1)(denoted N_(0),N_(80),N_(160),N_(240),and N_(320),respectively),were used in this study,and each treatment was replicated three times using a randomized complete block design.In both seasons,dry matter accumulation(DMA)of forage sorghum at the jointing,heading,flowering,and filling stages showed an increasing trend with successive increments in N application rate.At the harvest stage in 2019 and 2020,the DMA of forage sorghum increased initially and then decreased with further increase in N application rate,and DMA peaked at N_(160) with values of 22.3 t·ha^(-1) in 2019 and 18.0 t·ha^(-1) in 2020.As the growing season progressed,dry matter proportion(DMP)of leaves in forage sorghum gradually decreased,while DMP of stems initially increased and then decreased.At the harvest stages,the DMP of stems was the highest with average values of 70.8%in 2019 and 73.8% in 2020.In 2019,compared to N_(0),the N fertilization treatments significantly increased DMP of ears and decreased DMP of stems,however,no significant difference was observed in 2020.In 2019,there were no significant differences in water consumption(WC)and water consumption rate(WCR)of forage sorghum among the different treatments.In 2020,the WC of forage sorghum in the treatments varied from 483.4 to 505.8 mm,and the WCR varied from 3.1 to 3.3 mm·d^(-1).Compared to N_(0),the WC in 2020 was significantly increased by 4.6%in N_(80) and by 3.9%in N_(320),respectively,and the WCR in 2020 was significantly increased by 6.5%in both N_(80) and N_(320).The water u

关 键 词：饲用高粱 施氮量 干物质积累 耗水量 水分利用效率 

分 类 号：S544.9[农业科学—作物学]