All of the listed factors - birds, dust blowing, rain, and wind blowing - can contribute to the spread of plant diseases

Statement 1 is correct: Birds can act as vectors, carrying and spreading plant pathogens from one location to another through their feathers, feet, or droppings.

Statement 2 is correct: Dust and soil particles blown by the wind can carry and spread plant diseases, especially fungal spores and bacterial cells.

Statement 3 is correct: Rain can splash and disperse plant pathogens, such as fungi and bacteria, from the soil or infected plant parts to uninfected plants.

Statement 4 is correct: Wind can transport and spread airborne plant pathogens, such as fungal spores and bacterial cells, over long distances.