NEW YORK/CHICAGO (Reuters) - Walmart Inc’s patent filings hint that it may see a future where farmers use its drones to not only spot crop problems but selectively apply chemicals or even disperse pollen to bring shoppers the freshest and cheapest food possible. The world’s largest retailer applied for six patents last year on drones that aim to prevent damage to crops, control pest attacks on farms and cross-pollinate plants, according to U.S. Patents and Trademark Office documents that were made public last week and seen by Reuters. {snip} .....The market for agricultural drones will top $1 billion by 2024,...