Iqbal Nadeem, Manalil Sudheesh, Chauhan Bhagirath Singh, Adkins Steve
School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD 4343, Australia.
The Centre for Crop Science, Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Gatton, QLD 4343, Australia.
Plants (Basel). 2021 May 1;10(5):910. doi: 10.3390/plants10050910.
An elevated atmospheric carbon dioxide (CO) concentration and frequent droughts are two anticipated climate change scenarios in which certain invasive weeds may develop competitive advantages over crops and adversely impact productivity and herbicide efficacy. Hence, a study was conducted to explore the effect of different climatic scenarios on the growth and management of (Retz.) Pers with glyphosate. The variables investigated were two CO concentrations (400 and 700 ppm), two soil moisture levels (100% and 50% of field capacity (FC)), and three glyphosate rates (0 (control), 517 (50% of recommended rate), and 1034 g ae ha (recommended rate)). CO concentrations and soil moisture levels had different effects on the growth and management of . Overall, 100% FC and elevated [CO] of 700 ppm recorded the maximum plant height (38 cm), leaves per plant (20), growth index (60), chlorophyll content (SPAD value 37), and dry biomass (3 g) in comparison with ambient [CO] of 400 ppm and 50% FC treatment. The recommended glyphosate application gave 100% weed biomass reduction; however, efficacy was reduced (63%) when applied at 50% of the recommended rate under elevated [CO] of 700 ppm and 50% FC conditions.
大气中二氧化碳(CO₂)浓度升高和频繁干旱是两种预期的气候变化情景,在这些情景下,某些入侵杂草可能会比作物形成竞争优势,并对生产力和除草剂效果产生不利影响。因此,开展了一项研究,以探讨不同气候情景对小飞蓬(Conyza canadensis (L.) Cronq.)生长及草甘膦防除效果的影响。研究的变量包括两种CO₂浓度(400和700 ppm)、两种土壤湿度水平(田间持水量(FC)的100%和50%)以及三种草甘膦用量(0(对照)、517(推荐用量的50%)和1034 g ae/ha(推荐用量))。CO₂浓度和土壤湿度水平对小飞蓬的生长及防除效果有不同影响。总体而言,与400 ppm的环境CO₂浓度和50% FC处理相比,100% FC和700 ppm的升高[CO₂]条件下,植株最高(38厘米)、单株叶片数(20片)、生长指数(60)、叶绿素含量(SPAD值37)和干生物量(3克)均达到最大值。推荐的草甘膦用量可使杂草生物量减少100%;然而,在700 ppm升高[CO₂]和50% FC条件下,按推荐用量的50%施用时,防除效果降低(63%)。