Physiological limitations in two sugarcane varieties under water suppression and after recovering

Abstract

Increasing water scarcity and depleted water productivity in irrigated soils are inducing farmers to adopt improved varieties, such as those with high-capacity tolerance. The use of tolerant varieties of sugarcane might substantially avoid the decline of productivity under water deficit. This research aimed to evaluate the harmful effects of drought on the physiology of two sugarcane varieties (RB867515 and RB962962) during the initial development. Young plants were subjected to irrigation suspension until total stomata closure, and then rewatered. Significant reduction on stomatal conductance, transpiration, and net photosynthesis were observed. RB867515 showed a faster stomatal closure while RB962962 slowed the effects of drought on the gas exchanges parameters with a faster recovering after rewatering. Accumulation of carbohydrates, amino acids, proline, and protein in the leaves and roots of the stressed plants occurred in both varieties, substantially linked to reduction of the leaf water potential. Due to the severity of stress, this accumulation was not enough to maintain the cell turgor pressure, so relative water content was diminished. Water stress affected the contents of chlorophyll (a, b, and total) in both varieties, but not the levels of carotenoids. There was a significant reduction in dry matter

Early-Arbuscular Mycorrhizal Fungi-Application Improved Physiological Performances of Sugarcane Seedling and Further Growth in the Dry Land

“…According to Medeiros et al (2013), chlorophyll content of sugarcane is determined by varities. According to Zhao et al (2005), chlorophyll content is determined more by the content of N than P, and K. Meanwhile, the presence of mycorrhizae tends to increase the uptake of P for plants (Schachtman et al, 1998;S.…”

Respon Fisiologis Tanaman Tebu Terhadap Kekeringan, Physiological Responses of Sugarcane Plant to Drought

“…Cekaman kekeringan pada tebu menyebabkan penurunan konduktansi stomata, transpirasi, dan fotosintesis netto (Medeiros et al 2013). Pada genotipe peka (RB867515) penurunan hingga pada hari ke empat, sedangkan pada genotipe toleran (RB96262) penurunan berlangsung lebih lambat hingga hari ke delapan.…”

“…Efisiensi penggunaan air irigasi baik berdasar pada kg tebu maupun kg gula juga menurun. Medeiros et al (2013) melaporkan bahwa bobot kering bagian atas pada genotipe peka (RB867515) menurun nyata, demikian pula bobot kering akar, dan biomas total, namun pada tanaman tebu genotipe toleran (RB96262) kekeringan tidak berbengaruh nyata Pada kondisi stress air sedang nilai partisi sukrosa sekitar 33%. Menurut Inman-Bamber (1988) kenaikan biomass, meningkatkan rendemen baik pada tanaman PC maupun RC.…”

Intercomparação de modelos de simulação da cana-de-açúcar e seu uso na avaliação da quebra de produtividade e dos impactos da irrigação em diferentes regiões do Brasil

“…Cultivares de cana-de-açúcar tolerantes à deficiência hídrica podem minimizar as perdas de produtividade em condições de sequeiro (INMAN-BAMBER;MACHADO et al, 2009;MEDEIROS et al, 2013 .…”

“…Cultivares de cana-de-açúcar tolerantes à deficiência hídrica podem minimizar as perdas de produtividade em condições de sequeiro (INMAN-BAMBER;MACHADO et al, 2009;MEDEIROS et al, 2013). Os modelos de simulação de culturas podem contribuir com os programas de melhoramento genético da cana-de-açúcar no entendimento da relação genótipo-ambiente em locais com limitação de recursos hídricos .…”