The effect of drought stress on yield, leaf gaseous exchange and chlorophyll fluorescence of dry beans (Phaseolus vulgaris L.)

Abstract

Highlights • Drought stress across all stress levels resulted in a reduction in dry matter production, leaf area index, number of seeds per plant, number of pods per plant, seed size and finally grain yield. • The highest WUE was found in the treatment which was irrigated on fortnightly bases from 36 DAP. The results suggest that drought stress towards the end of the growing season may not cause serious harm in grain yield. • The results suggest that drought stress can be practiced in dry bean production in areas where there is a challenge of irrigation water with consideration of the growth stage of the crop. • The results of the study indicate that drought stress effects on photosynthetic rate were highly significant. • Chlorophyll fluorescence was also affected by drought stress.

Effect of Drought Stress on Certain Morphological and Physiological Characteristics of a Resistant and a Sensitive Canola Cultivar

“…Studies have shown that in drought stress, plant pigments such as carotenoids, chlorophyll a, chlorophyll b, total chlorophyll concentration significantly decreased, with lower results in pigment content in Ks7 compared to the NIMA. Previous studies on plants such as beans, chickpea and wheat showed that drought stress reduced the amount of chlorophyll a and b . Total chlorophyll concentration decreases with increasing drought stress and with increasing the concentration of PEG .…”

“…Previous studies on plants such as beans, chickpea and wheat showed that drought stress reduced the amount of chlorophyll a and b. [28,29,30] Total chlorophyll concentration decreases with increasing drought stress and with increasing the concentration of PEG. [31] Chlorophyll b decreased compared to chlorophyll a due to drought stress, which increased the chlorophyll b/a ratio, which was consistent with the results of Ashraf et al [32] Navabpour et al [33] reported that increasing amounts of carotenoids under drought stress conditions were anticipated due to their role in the antioxidant defense system that protects photosynthetic pigments (chlorophyll).…”

ESTUDO FITOQUÍMICO DE Hydrangea sp. POR MEIO DE MÉTODOS CLÁSSICOS DE ANÁLISE POR ESPECTROSCOPIA NO ULTRAVIOLETA VISÍVEL (UV-VIS) E CROMATOGRAFIA EM COLUNA E EM PAPEL

“…Em sua maioria, os pesquisadores discutem sobre a presença e o comportamento da clorofila a e b (Figura 2) e dos seus pigmentos acessórios (carotenos e xantofilas) (9,(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27). A concentração de clorofila e de seus pigmentos acessórios pode variar dependendo das condições de cultivo da planta (28)(29)(30)(31). A capacidade que a clorofila e seus pigmentos acessórios possuem de absorver luz na região do visível do espectro eletrônico, deve-se à resso-nância das insaturações, que caracterizam os grupos cromóforos (5).…”

Alfalfa and Its Symbiosis Responses to Osmotic Stress

“…With full ield capacity irrigation, high growth and stable yield could be achieved but require high amounts of water and high cost of accompanying farming practices. The water requirements of each crop vary at diferent stages of plant development and genotype, sensitivity of its physiological state, soil structure and property, climatic conditions and agricultural practices [28]. To avoid water stress damage during the growth phase, deicit irrigation could be an additional method to improve water productivity (WP) in alfalfa and other crops especially in areas where water resources are limited or production costs are high [70], as in the case of the arid regions of Morocco where the cultivation of lucerne is conducted only by irrigation.…”

“…It has been shown that decreasing water content and ion concentration in water-deicient leaves are more limiting for photosynthesis than closure of stomata [26]. Water stress also causes considerable disturbance of photosynthetic pigments in the photosystem (PS) II, leading to degradation of thylakoid membranes [27] and reduction of chlorophyll content, afecting their components [28]. Chlorophyll b (Chl b) is more afected than chlorophyll a (Chl a) [29].…”