Root growers are reminded that the time for applying Fazor (maleic hydrazide) to carrots and parsnips to suppress re-growth and to help maintain quality is fast approaching. Fazor has a SOLA for use in these crops and can be used in carrots and parsnips up until the end of 2007, without fear of exceeding the MRL.
To get the best from Fazor, it should be applied using a conventional sprayer when the crop foliage is mature, but not actively growing. It is typically applied to the crop from mid October onwards at 5-25% leaf yellowing or necrosis and when the crop begins to lean. Application is sometimes made in early November to carrots if the summer is dry and a wet autumn encourages a late growth flush. Application timing must be judged on a crop by crop basis but must be before the first frost.
The majority of the foliage needs to be green but not actively growing for Fazor to be translocated to the roots. On balance it is better that applications are made slightly later than too early as this can cause yield reduction if the canopy is not mature. Fazor should not be applied less than 3 weeks before harvest. If the crop is to be over-wintered, allow at least 4 days after application before topping or covering the crop for frost protection.
Fazor will inhibit respiration and suppress cell division in the crop and this stops development of whole top growth and of external lateral root hairs in the following spring. As root hairs grow, the plant would normally metabolise sugars and consequently quality is affected. Fazor stops this process and so helps to maintain the taste, tenderness and processing quality of the over-wintered root crop.
In parsnips, Fazor stops woody core and glazing in late-lifted crops and optimises market value. Prolonging the time that carrots and parsnips can be left in the ground, and so extending the lifting period, means that loading into pack houses is spread and the season is extended for locally supplied produce. It means that the supermarkets can more easily source supplies of home grown UK root vegetables.
Growers need to obtain a copy of the notice of approval to use Fazor in carrots and parsnips via the PSD web site, ADAS offices, the HDC or NFU. The SOLA reference number for Fazor on outdoor carrots and parsnips is 2159/2001.
Fazor contains 60% w/w maleic hydrazide, formulated as a water-soluble granule and is packed in a 2.5 kg bag. It is recommended on second earlies and maincrop potatoes as well as bulb onions, garlic and shallots. It has SOLAs in parsnips and carrots. In carrots, Fazor is recommended at a dose rate of 15 kg/ha in 350-500 litres of water per hectare and in parsnips the recommended dose rate is 10 kg/ha, with a maximum number of applications of 1 per crop. Rain or irrigation within 24 hours of application may reduce effectiveness. Fazor can be used in conjunction with black polythene for in-field storage.
