夏秋高温干旱对不同下种时间甘蔗产量性状的影响

Effect of High Temperature and Drought in Summer and Autumn onYield Traits of Sugarcane Planted at Different Planting Times

近年来在全球气候变暖加剧的背景下,广西极端天气频发,夏秋高温少雨干旱发展加重,严重影响甘蔗生产,科学选择适宜的下种时间,是应对夏秋干旱灾害的一个重要途径。本研究于2021、2022年在广西柳州沙塘国家农业气象试验站设置甘蔗农田试验点,采用3个甘蔗品种,2—5月进行7期分期下种田间试验,通过利用这2个年度典型的夏秋高温干旱年景,研究夏秋高温干旱对不同下种时间甘蔗产量性状的影响。试验结果表明:(1)在夏秋高温干旱年景条件下,随着下种时间的延迟,甘蔗收获期茎长、茎粗、单茎重、理论产量均呈现明显下降的趋势,2021、2022年下种时间A1各品种茎长为178~227 cm,茎粗为27.6~30.3 mm,单茎重为1.05~1.42 kg,下种时间A7各品种茎长仅为76~145 cm,茎粗为21.5~30.0 mm,单茎重为0.26~0.85 kg;(2)在3月种植的新植蔗,理论产量在76.65~104.10 t/hm^(2)之间,甘蔗能利用前期比较适宜的气象条件,缓解夏秋高温干旱对甘蔗的影响;在4—5月期间种植的新植蔗,受干旱影响较大,其中5月30日下种理论产量仅为18.90~63.75 t/hm^(2),甘蔗产量显著下降;(3)甘蔗品种ROC22和GL05136在茎长、单茎重和理论产量方面比GT42有优势,但是在茎粗方面GT42有优势,ROC22和GL05136抗旱性较强。因此,在夏秋高温干旱年景下,选择适宜抗旱品种,春种甘蔗尽量适时提早种植,加快甘蔗前期生长进度;在夏秋干旱来临之前,获得健壮植株,提高自身抗旱能力,将气象灾害影响降到最低,可达到高产、稳产的目的。

In recent years,under the intensifying global warming,extreme weather has occurred more frequently in Guangxi,presenting higher temperature and less rainfall in summer and autumn.The worsened drought has seriously affected sugarcane production.Scientifically selecting an appropriate planting time is an important way to cope with the summer and autumn drought.A sugarcane field test was conducted at the Shatang National Agricultural Meteorological Experimental Station in Liuzhou,Guangxi in 2021 and 2022.By utilizing typical hot and dry seasons in summer and autumn,the field experiments were conducted with three sugarcane varieties and the seedcanes were planted at seven different times from February to May to study the impact of summer and autumn hot and dry conditions on sugarcane yield traits at different planting times.The experimental results indicated that:(1)Under the conditions of high tem-perature and drought in summer and autumn,delayed planting tended to decrease the stalk length,stalk diameter,single stalk weight,and theoretical cane yield at harvest.Planting time A1 in 2021 and 2022,the stalk length of each variety was 178–227 cm,stalk diameter was 27.6–30.3 mm,and single stalk weight was 1.05–1.42 kg,while planting time A7,the stalk length was only 76–145 cm,stalk diameter was 21.5–30.0 mm,and single stalk weight was 0.26–0.85 kg.(2)Planting sugarcane in March resulted in the cane yield between 76.65 t/hm^(2) and 104.10 t/hm^(2).Sugarcane could utilize the favor-able meteorological conditions at the early stages to alleviate the impact of summer and autumn heat and drought on sugarcane.The sugarcane crops planting from April to May was significantly affected by drought,Planting sugarcane on May 30th with a theoretical yield of only 18.90 t/hm^(2) and 63.75 t/hm^(2),resulting in a significant decrease in cane yield.(3)Sugarcane varieties ROC22 and GL05136 had advantages over GT42 in stalk length,single stalk weight,and cane yield,but GT42 had advantage in stalk thickness,meaning ROC22 and GL05136 having stronger drought resistance.Therefore,under the conditions of high temperature and drought in summer and autumn,suitable drought resistant sug-arcane varieties should be selected,and sugarcane should be planted as early as possible to accelerate the early growth and development progress of sugarcane.Before the onset of summer and autumn drought,robust plants should be ob-tained to improve their drought resistance,in order to minimize the impact of meteorological disasters,and achieve high and stable yields.