How could a decrease in blood pressure affect filtration in the kidney?

Hint: The kidneys perform a wide variety of functions which are necessary for health. They excrete out the metabolic waste, regulate fluid and balance electrolyte, promote the bone integrity, and many more functions.

Complete answer:
These are two bean-like organs which interact with the cardiovascular system in order to maintain hemodynamic stability. Renal blood flow (RBF) and glomerular filtration are some important aspects of sustaining proper organ functions. A healthy balance needs to be present between renal blood flow and the glomerular filtration rate as the changes in one may affect the other one.
Increases in the glomerular capillary hydrostatic pressure cause increases in net filtration pressure and GFR. However, increases in Bowman space hydrostatic pressure causes decreases in filtration pressure and GFR. This may result from ureteral constriction.
The glomerular filtration rate (GFR) is known as the amount of fluid filtered through the glomerulus into Bowman’s capsule in per unit time.
Renin is produced by the juxtaglomerular cells in response to the decreased renal arterial pressure. If the GFR is very low, metabolic wastes will not get filtered from the blood into the renal tubules. If the Glomerular filtration rate is very high, the absorptive capacity of salt and water by the renal tubules becomes overwhelmed. The autoregulation system manages these changes in GFR and RBF.

Note: This is because the blood travelling at the afferent arteriole will have a lower blood pressure.If the blood pressure is low at the afferent arteriole then the hydrostatic pressure pushing the fluid through the glomerulus will be low. Less fluid will be filtered through due to the vey low blood pressure.