NEW FODDER DISEASE.

Putaruru Press, Volume IV, Issue 115, 7 January 1926, Page 4

NEW FODDER DISEASE.

MENACE TO LUCERNE. » Measures of Control. A menacing lucerne disease of farreaching importance to the growers of the king of fodder crops has just been recorded by the scientists of the Department of Agriculture for the first time in New South Wales. It is known . as stem nematode, or eel worm, di- iA soase, from, the fact that this ncmatoclajp (Tylenchus dipsaci), is responsible forthe condition. 1 Although in recent years the Agricultural Department has been called upon to investigate a number of instances of failure of lucerne, and several fungi have been found commonly associated with the condition, this is the first instance in which the nematode in question has been found infecting the crop. Tho disease is known to occur in South x\frica and in the United States, where it is flow regarded as a most serious menace to lucerne. The field symptoms of the s disease, as described by Dr. Noble, principal assistant biologist, are that the occurrence is generally in localised areas, and is marked by poor stands, with reduced number of stems, some of which are yellowed and distorted. Wilting is 'sometimes deserved. Stems which are iffl swollen at the base and brown in colour, become brittle, and break easily. Plants may be killed outright. New JL 'buds and sprouts are often and pale yellowish or cream in These new shoots do not move away the spring, and may remain in this arrested condition of growth for from three to four months. The swollen tissues contain hundreds of nematodes—parasitic, thread-like organisms, approximately .l-20th of an inch in length. The organism does not occur in the roots. They are very resistant to drying, and may be carried long distances in hay, and are easily transferred mechanically by farm implements, surface waters, etc. The nematode is known to occur in a number of common weeds, even affecting the seed in some cases. It has not yet been established that it can W. affect lucerne seed, although it has ~ been found in clo\’cr seed. The only control measures are preventive ones. It is a most difficult disease to cope w’ith, and eradication is suggested wherever possible. The orThis may involve the removal of lucerne from affected areas for three years. The removal of. lucerne and susceptible weeds must be complete, or the measure remains ineffective. Care must also be taken that the implements are cleaned and disinfgected before use on clean lands. These measures are • difficult to apply in consideration of the fact that so much attention must be paid to the details involved, hence the desirability of early action wherever situation should so demand it. . Inc authentic location of the disease jn New South Wales started at the end of last month on the receipt of some infected lucerne roots from the Hunter River district. A visit which ' was promptly made by Dr. Noble revealed the presence yf the disease, also that it probably exists around Mait-„ • land anil Raymond Terraco. , In some fields the stand liad been materially reduced. The most severely affected area contained SO per cent, of diseased plants. Several of the e-row-ers considered that, they would be able I to cut the affected .areas once only this season. J The opinion was expressed by growms that the disease has been present v ' a Pcr'pd- ranging up to 18 lea s ..although its true nature was en-' ,„U% " U J known ' , Indications are that it na> been spread mainly by water in 1 h cultivation implements, *■ . an, m other cases by live stock. eA?F ri « CS of . chcck observations on the wUh <, ? amams now in progress, i null a view to publication in ' due c rr v aU data - - disease.—Daily Telegraph,. Syd-