Does the Introgression of Bt Gene Affect Physiological Cotton Response to Water Deficit?

Abstract

Water deficit may affect the expression of lepidoptera-controlling proteins in cotton. However, it is unknown if there is a differential response of conventional and Bt cotton cultivars to water deficit, what could potentially affect the plant competition with weeds. The objective of this work was to investigate the response of Bt cotton cultivars to water deficit compared with their conventional near-isolines. The experiment was conducted in a greenhouse, where the cotton cultivars FMT 705, FMT 709 and IMACD 8276, with and without the Bt gene, were grown under two water regimens: 100% and 50% (moderate water deficit) of available soil water. Cotton phenology was severely affected by moderate water deficit, with a reduction in shoot and root dry matter production, root length and diameter, plant height and leaf area. No effect of the Bt gene was observed. Water deficit during cotton flowering decrease stomatal conductance, net assimilation of CO2 and transpiration rates. The leaf water potential is lower in plants exposed to a moderate water deficit compared with non-stressed plants. However, the introgression of the Bt gene does not modify cotton physiological and phenotypic response to water deficit.

Exogenous salicylic acid-induced drought stress tolerance in wheat (Triticum aestivum L.) grown under hydroponic culture

“…An infrared gas analyzer (IRGA) was used for photosynthetic rates [ 37 , 38 ]. The measurement was done through non-destructive sampling (without excising leaf from the parent plant).…”

“…Owing to osmosis, gravity, mechanical friction, and matrix effects such as capillary movement, water often travel from high water potential to lower water potential. Water potential apparatus (Pressure chamber, Model 600, PMS International Company) had been used to assess leaf water potential by following the protocol [ 38 , 39 ]. A single incised fresh leaf was stocked down in the chamber, and incised surface was kept out from the hole of instrument.…”

“…Five measurements were noted from five different plants in each treatment, and then mean values were taken. Transpiration and photosynthesis rates were also determined on leaf attached to the plant by using infrared gas analyzer (IRGA) [ 37 , 38 ]. Five measurements were recorded from five different plants in each treatment, and then average was taken.…”

“…It was measured by infrared temperature sensors (IRIS). It gives information on plant water use, water status, and precisely how a plant is metabolically active [ 37 , 38 ].…”

Rice Straw Vermicompost Enriched With Cellulolytic Microbes Ameliorate the Negative Effect of Drought in Wheat Through Modulating the Morpho-Physiological Attributes

“…Canopy temperature, an indicator of energy emitted by wheat plants, was measured by using IRIS infrared temperature sensors. Furthermore, IRGA-infrared gas analyzer was used to measure the photosynthesis and transpiration rates, following the procedure of Singh et al (2018) and Rosolem et al (2019) where five measurements were taken. An average value was used thereafter.…”