List of top Life Science Questions on Plant Sciences asked in GATE XL

Which one of the options given correctly matches the alkaloids in Group I with their source plants in Group II?

Match the following rice diseases in Group I with their causal agents in Group II.

Periderm is a protective tissue found in stems and roots of gymnosperm and woody dicotyledons. It contributes to the increased thickness by secondary growth. Match the peridermal components given in Group I with the cell/tissue types given in Group II. 

The schematic depicts an unexpanded plant cell within a hypocotyl with the arrangement of cellulose microfibrils marked on its cell wall.

Blue light can directly induce opening of stomata. Blue light also triggers photosynthesis in the guard cells, which indirectly induces stomatal opening. Which one or more of the following experimental approaches would test the direct effect of blue light on stomatal opening?
A cytoplasmic male-sterile female plant with the restorer (nuclear) genotype rr is crossed to a male-fertile male plant with the genotype RR. Both RR and Rr can restore the fertility, whereas rr cannot. When an F1 female plant with Rr genotype was test-crossed to a male-fertile male plant with the rr genotype, the percentage of the population that is male fertile would be _______. (Answer in integer)
Central vascular cylinder or stele consists of the primary vascular system (xylem and phloem) and the associated fundamental tissue. Match the schematics of stele in Group I (xylem shown in green, and phloem shown as with their respective types in Group II. \includegraphics[width=0.75\linewidth]{image58.png}
Consider four observations about the FT gene and flowering transition in the shoot apical meristem (SAM) of Arabidopsis thaliana:
(i) The FT promoter is active in leaves alone.
(ii) The ft null mutation causes delayed flowering of the SAM.
(iii) Expressing a recombinant FT protein fused to a nuclear localization signal (NLS) under the endogenous promoter does not rescue the delayed-flowering phenotype of the ft null mutant.
(iv) Downregulation of FT transcript in the SAM by RNAi in a wild-type background does not alter flowering.
Which conclusion best explains these observations?
Which one or more of the following statements is/are NOT CORRECT with respect to pollen development in angiosperm?
Regulation of phosphoenolpyruvate carboxylase (PEPCase) governs CO2 fixation in both C4 and CAM (crassulacean acid metabolism) plants. Which one or more of the following statements with respect to PEPCase activity is/are CORRECT?
Which one or more processes listed below DOES NOT produce carbon dioxide during fermentation?
Which one of the following statements on Casparian strips is correct?
Rotenone is a chemical often used to kill insect pests on crop plants and fishes in lakes. Rotenone acts by inhibiting electron transport from the NADH dehydrogenase enzyme in Complex I to ubiquinone in the mitochondrial electron transport chain. Which one of the following explains why plants can tolerate rotenone application?
Although Pseudomonas syringae infection in plants is actively inhibited by the endogenous salicylic acid (SA) of host origin, a successful infection is still established because the bacterium secretes coronatine, an effector molecule. Which one of the following best describes the mode of action of coronatine?