Morphological changes recorded in different phenophases of sugarcane plants subjected to water stress in tropical field conditions

Abstract

Nowadays, water deficit is one of the major environmental stress issues affecting sugarcane crops around the world. It has been causing significant production decrease due to the increased mortality rates generated by water stress in sugarcane plantations. The aim of the current study is to assess sugarcane morphological and yield responses during different phenophases of sugarcane varieties when plants are subjected to drought stress in the fields of a tropical region. Six sugarcane varieties, namely: SP79-1011, RB855113, RB92579, RB867515, RB72454, and RB855536, were subjected to water stress. The herein adopted water regimes were (i) irrigated crop and (ii) crop subjected to natural drought in the field. Plants were cultivated under water stress imposition throughout three phenological stages (i) tillering, three months after planting; (ii) intense growth, seven months after planting; and (iii) ripening, eleven months after planting. The irrigation treatment consisted of supplementing the crop with 50 mm of water per month during the dry season, whereas non-irrigated plants were naturally grown under water stress conditions throughout the experiment. Water stress mostly affected the sugarcane crop during the intense growth phase. Varieties RB72454 and RB855536 presented smaller green-leaf number, as well as narrower leaf width and smaller leaf area under water stress; besides, they showed low productive potential and high stress susceptibility index (SSI). Stalk height maintenance and the larger number of tillers in RB92579 plants subjected to water stress helped balancing yield rates. This variety also showed the best drought tolerance (DTI) and yield/tolerance indices (YTI); moreover, the principal component analysis evidenced that leaf area, plant height and yield were important factors to distinguish the most tolerant varieties. Such results show that RB92579 is more drought tolerant and has better physiological acclimation potential than the other five varieties; therefore, it can be recommended for crops subjected to drought periods.

Inter‐relationship between photosynthetic efficiency, Δ13C, antioxidant activity and sugarcane yield under drought stress in field conditions

“…Drought is one of the main climatic factors that currently affects the world's cultivated areas and reduces the crop yielding, including sugarcane (Endres et al, ; Jangpromma et al, ; Silva et al, ; Zhao & Li, ). Moreover, current climate change may increase the effects of drought and hence reduce the availability of water for agriculture (Abdallah, Moses, & Prakash, ).…”

Understanding drought responses of sugarcane cultivars controlled under low water potential conditions

“…In sugarcane, there has been a lack of research under hydroponics, even though drought is identified as a main factor to reduce leaf area under field (Begum et al, 2012;Zhao et al, 2012) and pot conditions (Patade et al, 2011). However, the responses for leaf area have varied among different genotypes and drought intensities (Endres et al, 2018). Drought tolerant research on cowpeas grown in a hydroponics system was reported by Ogbonnaya et al (2003), who found that drought-resistant varieties could better maintain leaf area than a susceptible variety.…”

Induction of drought tolerance by inoculation of Bacillus aryabhattai on sugarcane seedlings

“…The sensitivity of sugarcane to this abiotic factor is determined by the genetic code. In the condition of introduced and natural water deficit, the varieties, RB72-454 and RB85-5536, produce less leaves than SP79-1011, RB86-7515, RB85-5113, and RB92-579, which present higher loads and provide more tillers per plant (Endres et al, 2018). Under water stress, B. subtilis and B. megaterium induce growth in sugarcane cultivation by stimulating the synthesis of acidic invertases, enzymes that hydrolyze sucrose, polysaccharide stored in photosynthetic tissues, and incomplete stem parenchyma.…”

“…Although technically efficient, this propagation method is unlikely to be sensitive to water deficit; in planting, there will be intense dehydration of PSS, if the availability of water in the soil is not sufficient to the meet evapotranspiration demand of the crop. The main consequences are undoubtedly: generalized mortality, unsatisfactory productive yield of high-quality raw material, and inevitably unsustainable cost of production (Agroanalysis, 2017;Endres et al, 2018).…”