Broom's Barn Applied Crop Sciences

The first samples to the plant clinic arrived mid April and were from fields showing signs of quite severe thrip (commonly called thunder flies) damage. Thrips tend to feed on the young heart leaves leaving a charred (blacken) looking centre to the plant. Most of these crops will have recovered, albeit with some retarded growth.

During May and June a number of samples with herbicide damage were sent in. There were a variety of causes such as spray drift, sprayer tank contamination and residues in the soil from herbicide applications made to previous crops. Compaction, which can lead to deficiencies, as the roots cannot make use of readily available nutrients within the soil, was the cause of a number of the symptoms seen in plant clinic submissions. It is well worth examining the soil structure surrounding sugar beet plants that are not performing well prior to submission to the clinic.� Soil pests - beet cyst nematode (BCN) reared their ugly heads again with quite an early find in the first week of May.� With the beet rotation more commonly one year in 3, this problem seems to be occurring more and more. Free living nematodes (Trichodorus and Longidorus) have only accounted for two plant clinic samples. Root knot nematode (Meloidogyne), surprisingly, has appeared twice, this may well be due to the warmer spring and summer climate we now experience in this country. This nematode has a wide host range making it difficult to control.

Summer

July saw an invasion of silver Y moth to a large number of sugar beet fields and consequently samples of leaf damage being submitted to the plant clinic and requests for information on control measures. Rust, cercospora and alternaria, also started arriving at the clinic, although cercospora did not take off as much as was first predicted. Rust did, however, appear in all factory areas in July with samples being submitted to the clinic for confirmation during the following months. There were a number of root rot cases this season, some of which were fusarium occurring as a secondary pathogen. The most probable cause would be damage to the root including root splitting caused when the late spring drought conditions ended and the beet then taking on a sudden growth spurt during the august rains.� The damage to the roots allowed the secondary fusarium infection to take hold. �There were also a few incidences with late aphanomyces, here the root was probably a survivor of an earlier infection and went on to produce the symptoms of a strangled centre, to the root, in later growth.