On Pesach we are judged by G-d concerning the grain of the coming year (ר”ה טז,א). In the merit of the matzos that we eat during Pesach we merit to a year of plenty for the entire year. This is hinted in that the name for matza matza lechem ony (מצה לחם עני=343) has the same numerical value as the word for rain (גשם=343), and all of livelihood is dependent on rain.
(בני יששכר חודש ניסן מאמר ח אות יב)