GRUBS AND DISEASE ATTACK LUCERNE

Press, Volume XCII, Issue 27736, 13 August 1955, Page 5

GRUBS AND DISEASE ATTACK LUCERNE

REPORTS FROM NORTH OTAGO increasing use of lucerne in North Otago is shown by the many young stands which are now doing well in the district In spite of exceptional autumn and early winter growing conditions whch have been in favour of late sowings, the December-January sowings are much better established. It has been noted throughout the province that a number of stands sown in February-March nave suffered from damping-off fungus. This fungus has been under observation for the last two seasons and it appears that where stands have struck well they tend to thin out progressively and may ultimately be severely damaged. There are several causes for this thinning out, the most likely of these being grass grub and damping-off. There are sufficient differences in the appearance of stands damaged by either to assist farmers in identifying the cause. In the case of damping-off the plants do not wither and yellow, rather thev remain stunted, turn a bronze colour without appearing wilted and then die. when damage by grass grub is severe the plot wilts, withers and dies without becoming bronze in colour. Both tend to occur in patches, but with grass grub it is probably much more defined; • Odd damping-off plants can be found practically throughout a stand where damage is in evidence. Soil conditions and temperature probably affect the onset of damping- °«- This is predominantly a disease of seedlings, whereas grass grub will attack a plant to several inches in height. As a general observation, it would appear that the late sowings are more prone to be affected by damping-off, mainly because soil conditions become less favourable for the seed. There is noJcnown control which can be applied to‘ prevent damping-off in