Robigus
Or feminine Robigo, Robigalia, is described by some Latin writers as a divinity worshipped for the purpose of averting blight or too great heat from the young cornfields.
The festival of the Robigalia was celebrated on the 25th of April, and was said to have been instituted by Numa (Virgil, Georgics, Fasti By Ovid).
But considering the uncertainty of the ancients themselves as to whether the divinity was masculine or feminine, and that the Romans did not pay divine honours to any evil demon, it is highly probable that the divinity Robigus, or Robigo, is only an abstraction of the later Romans from the festival of the Robigalia.
From Smith's Dictionary of Greek and Roman Biography and MythologyFrom The History of Rome by Theodor Mommsen. Book I. Chapter XII
As, when a war was to be waged, it began with this festival, so after the close of the campaign in autumn there followed a further festival of Mars, that of the consecration of arms (-armilustrium-, October 19). Lastly, to the second Mars, Quirinus, the 17th February was appropriated (-Quirinalia-). Among the other festivals those which related to the culture of corn and wine hold the first place, while the pastoral feasts play a subordinate part. To this class belongs especially the great series of spring-festivals in April, in the course of which sacrifices were offered on the 15th to Tellus, the nourishing earth (-fordicidia-, sacrifice of the pregnant cow), on the 19th to Ceres, the goddess of germination and growth (-Cerialia-) on the 21st to Pales, the fecundating goddess of the flocks (-Parilia-), on the 23rd to Jupiter, as the protector of the vines and of the vats of the previous year's vintage which were first opened on this day (-Vinalia-), and on the 25th to the bad enemy of the crops, rust (-Robigus-: -Robigalia-).
From Fasti By Ovid
On this day, returning to Rome from Nomentum,
A white-robed throng blocked my road.
A priest was going to the grove of old Mildew (Robigo),
To offer the entrails of a dog and a sheep to the flames.
I went with him, so as not to be ignorant of the rite:
Your priest, Quirinus, pronounced these words:
'Scaly Mildew, spare the blades of corn,
And let their tender tips quiver above the soil.
Let the crops grow, nurtured by favourable stars,
Until they're ready for the sickle.
Your power's not slight: the corn you blight
The grieving farmer gives up for lost.
Wind and showers don't harm the wheat as much,
Nor gleaming frost that bleaches the yellow corn,
As when the sun heats the moist stalks:
Then, dreadful goddess, is the time of your wrath.
Spare us, I pray, take your blighted hands from the harvest,
And don't harm the crop: it's enough that you can harm.
Grip harsh iron rather than the tender wheat,
Destroy whatever can destroy others first.
Better to gnaw at swords and harmful spears:
They're not needed: the world's at peace.
Let the rural wealth gleam now, rakes, sturdy hoes,
And curved ploughshare: let rust stain weapons:
And whoever tries to draw his sword from its sheath,
Let him feel it wedded there by long disuse.
Don't you hurt the corn, and may the farmer's
Prayer to you always be fulfilled by your absence.'
